Cylindrical linear asynchronous motor in the drive of high-voltage circuit breakers. CLD. Mitsubishi Electric EDM Drive Control System Cylindrical linear motor as a manuscript

As a manuscript

Bazhenov Vladimir Arkadievich

Cylindrical linear asynchronous motor in drive highvoltage switches

Specialty 05.20.02 - electrical technologies and electrical equipment in

dissertations for a degree

candidate of technical sciences

Izhevsk 2012

The work was carried out in the federal state budgetary educational institution of higher professional education "Izhevsk State Agricultural Academy" (FGBOU VPO Izhevsk State Agricultural Academy)

Scientific adviser: candidate of technical sciences, associate professor

Vladykin Ivan Revovich

Official opponents: Vorobyov Viktor Andreevich

doctor of technical sciences, professor

FGBOU VPO MGAU

them. V.P. Goryachkina

Bekmachev Alexander Egorovich

candidate of technical sciences,

project manager

CJSC "Radiant-Elcom"

Lead organization:

Federal State Budgetary Educational Institution of Higher Professional Education "Chuvash State Agricultural Academy" (FGOU VPO Chuvash State Agricultural Academy)

The defense will take place 28 » May 2012 in 10 hours at a meeting of the dissertation council KM 220.030.02 at the Izhevsk State Agricultural Academy at the address: 426069, Izhevsk, st. Student, 11, room. 2.

The dissertation can be found in the library of the FGBOU VPO Izhevsk State Agricultural Academy.

Posted on the website: www.izhgsha/ru

Scientific Secretary

dissertation council N.Yu. Litvinyuk

GENERAL DESCRIPTION OF WORK

Relevance of the topic. With the transfer of agricultural production to an industrial basis, the requirements for the level of reliability of power supply are significantly increased.

The target comprehensive program for improving the reliability of power supply to agricultural consumers /TsKP PN/ provides for the widespread introduction of automation equipment for rural distribution networks of 0.4 ... 35 kV, as one of the most effective ways achieving this goal. The program includes, in particular, equipping distribution networks with modern switching equipment and drive devices for them. Along with this, it is assumed that the primary switching equipment in operation will be widely used.

The most widespread in rural networks are oil switches (VM) with spring and spring-load drives. However, from operating experience it is known that VM drives are one of the least reliable elements. switchgears. This reduces the efficiency of complex automation of rural electrical networks. For example, in the studies of Sulimov M.I., Gusev V.S. it was noted that 30 ... 35% of cases of relay protection and automation (RPA) are not implemented due to the unsatisfactory condition of the drives. Moreover, up to 85% of defects are accounted for by VM 10 ... 35 kV with spring-load drives. Researchers Zul N.M., Palyuga M.V., Anisimov Yu.V. note that 59.3% of failures of automatic reclosing (AR) based on spring drives occur due to auxiliary contacts of the drive and the circuit breaker, 28.9% due to mechanisms for turning on the drive and keeping it in the on position. The unsatisfactory state and the need for modernization and development of reliable drives are noted in the works of Gritsenko A.V., Tsvyak V.M., Makarova V.S., Olinichenko A.S.

Picture 1 - Analysis of failures in electric drives ВМ 6…35 kV

There is a positive experience in the use of more reliable electromagnetic drives of direct and alternating current for VM 10 kV at step-down substations for agricultural purposes. Solenoid drives, as noted in the work of G.I. Melnichenko, compare favorably with other types of drives by their simplicity of design. However, being direct-acting drives, they consume a lot of power and require a bulky battery and charger or a rectifier with a special 100 kVA transformer. Due to the indicated number of features, these drives have not found wide application.

We have analyzed the advantages and disadvantages of various drives for CM.

Disadvantages of electromagnetic drives direct current: the impossibility of adjusting the speed of movement of the core of the closing electromagnet, the large inductance of the electromagnet winding, which increases the time of switching on the switch to 3..5 s, the dependence of the traction force on the position of the core, which leads to the need for manual switching, accumulator battery or a rectifier unit of high power and their large dimensions and weight, which occupies up to 70 m2 in the usable area, etc.

Disadvantages of AC electromagnetic drives: high power consumption (up to 100 ... 150 kVA), large cross-section of supply wires, the need to increase the power of the auxiliary transformer according to the condition of acceptable voltage drop, the dependence of power on the initial position of the core, the impossibility of adjusting the speed of movement, etc.

The disadvantages of the induction drive of flat linear asynchronous motors are: large dimensions and weight, starting current up to 170 A, dependence (dramatically reduced) of the traction force on the heating of the runner, the need for high-quality gap adjustment and design complexity.

The above disadvantages are absent in cylindrical linear induction motors (CLAM) due to their design features and weight and size indicators. Therefore, we propose to use them as a power element in drives of the PE-11 type for oil circuit breakers, which, according to the data of the West Ural Department of Rostekhnadzor for the Udmurt Republic, are currently in operation on the balance sheet of energy supply companies of the VMP-10 type 600 pieces, the VMG-35 type 300 pieces .

Based on the above, the following Objective: increasing the efficiency of the drive of high-voltage oil circuit breakers 6 ... 35 kV, operating on the basis of CLAD, which makes it possible to reduce damage from undersupply of electricity.

To achieve this goal, the following research tasks were set:

1. Conduct a review analysis of the existing designs of drives for high-voltage circuit breakers 6 ... 35 kV.
2. Develop a mathematical model of the CLA on the basis of a three-dimensional model for calculating the characteristics.
3. Determine the parameters of the most rational type of drive based on theoretical and experimental studies.
4. Conduct experimental studies of the traction characteristics of circuit breakers 6 ... 35 kV in order to verify the adequacy of the proposed model to existing standards.
5. To develop the design of the drive of oil circuit breakers 6 ... 35 kV based on the TsLAD.
6. Carry out a feasibility study on the efficiency of using the central control room for drives of oil circuit breakers 6 ... 35 kV.

Object of study is: a cylindrical linear asynchronous electric motor (CLAM) for driving devices of switches of rural distribution networks 6 ... 35 kV.

Subject of study: study of the traction characteristics of the CLIM when operating in oil circuit breakers 6 ... 35 kV.

Research methods. Theoretical studies were carried out using the basic laws of geometry, trigonometry, mechanics, differential and integral calculus. Natural studies were carried out with the VMP-10 switch using technical and measuring tools. The experimental data were processed using the Microsoft Excel program.

Scientific novelty of the work.

1. A new type of drive for oil circuit breakers is proposed, which makes it possible to increase the reliability of their operation by 2.4 times.
2. A technique for calculating the characteristics of the CLIM has been developed, which, in contrast to those proposed earlier, allows one to take into account the edge effects of the magnetic field distribution.
3. The main design parameters and modes of operation of the drive for the VMP-10 circuit breaker are substantiated, which reduce the undersupply of electricity to consumers.

The practical value of the work determined by the following main results:

1. The design of the VMP-10 circuit breaker drive is proposed.
2. A technique for calculating the parameters of a cylindrical linear induction motor has been developed.
3. A technique and a program for calculating the drive have been developed, which allow calculating the drives of switches of similar designs.
4. The parameters of the proposed drive for VMP-10 and the like are determined.
5. A laboratory model of the drive was developed and tested, which made it possible to reduce the losses of power supply interruptions.

Implementation of research results.

The work was carried out in accordance with the R&D plan of FGBOU VPO CHIMESH, registration number No. 02900034856 "Development of a drive for high-voltage circuit breakers 6 ... 35 kV". The results of the work and recommendations are accepted and used in the Production Association "Bashkirenergo" S-VES (an act of implementation has been received).

The work is based on a generalization of the results of studies carried out independently and in collaboration with scientists from the Chelyabinsk State Agricultural University (Chelyabinsk), the Prodmash Special Design Technology Bureau (Izhevsk), and the Izhevsk State Agricultural Academy.

The following provisions have been defended:

1. Type of oil circuit breaker drive based on CLAD.
2. Mathematical model for calculating the characteristics of the CLIM, as well as the traction force, depending on the design of the groove.
3. Methodology and program for calculating the drive for circuit breakers of the VMG, VMP types with a voltage of 10 ... 35 kV.
4. Results of studies of the proposed design of the oil circuit breaker drive based on the CLAD.

Approbation of research results. The main provisions of the work were reported and discussed at the following scientific and practical conferences: XXXIII scientific conference dedicated to the 50th anniversary of the Institute, Sverdlovsk (1990); international scientific-practical conference "Problems of energy development in the conditions of production transformations" (Izhevsk, FGBOU VPO Izhevsk State Agricultural Academy 2003); Regional Scientific and Methodological Conference (Izhevsk, Izhevsk State Agricultural Academy, 2004); Actual problems of mechanization Agriculture: materials of the anniversary scientific and practical conference "Higher agroengineering education in Udmurtia - 50 years." (Izhevsk, 2005), at the annual scientific and technical conferences of teachers and staff of the Izhevsk State Agricultural Academy.

Publications on the topic of dissertation. The results of theoretical and experimental studies are reflected in 8 printed works, including: in one article published in a journal recommended by the Higher Attestation Commission, two deposited reports.

Structure and scope of work. The dissertation consists of an introduction, five chapters, general conclusions and appendices, presented on 138 pages of the main text, contains 82 figures, 23 tables and lists of references from 103 titles and 4 appendices.

In the introduction, the relevance of the work is substantiated, the state of the issue, the purpose and objectives of the research are considered, and the main provisions submitted for defense are formulated.

In the first chapter the analysis of designs of switches drives is carried out.

Installed:

The fundamental advantage of combining the drive with the CLA;

Need for further research;

Goals and objectives of the dissertation work.

In the second chapter methods for calculating the CLAD are considered.

Based on the analysis of the propagation of the magnetic field, a three-dimensional model was chosen.

The winding of the CLIM in the general case consists of individual coils connected in series in a three-phase circuit.

We consider a CLA with a single-layer winding and a symmetrical arrangement of the secondary element in the gap with respect to the inductor core. The mathematical model of such a LIM is shown in Fig.2.

The following assumptions are made:

1. Winding current laid on length 2p, is concentrated in infinitely thin current layers located on the ferromagnetic surfaces of the inductor and creates a purely sinusoidal traveling wave. The amplitude is related by a known relationship with the linear current density and current load

, (1)

- pole;

m is the number of phases;

W is the number of turns in the phase;

I - effective current value;

P is the number of pairs of poles;

J is the current density;

Cob1 - winding coefficient of the fundamental harmonic.

2. The primary field in the region of the frontal parts is approximated by the exponential function

(2)

The reliability of such an approximation to the real picture of the field is evidenced by previous studies, as well as experiments on the LIM model. It is possible to replace L=2 s.

3. The beginning of the fixed coordinate system x, y, z is located at the beginning of the wound part of the incoming edge of the inductor (Fig. 2).

With the accepted formulation of the problem, n.s. windings can be represented as a double Fourier series:

Kob - winding coefficient;

L is the width of the reactive bus;

The total length of the inductor;

– shear angle;

z = 0.5L - a - zone of induction change;

n is the order of the harmonic along the transverse axis;

is the order of harmonics along the longitudinal axis;

We find the solution for the vector magnetic potential of the currents. In the air gap region, A satisfies the following equations:

For the SE equation 2, the equations have the form:

(5)

Equations (4) and (5) are solved by the method of separation of variables. To simplify the problem, we give only the expression for the normal component of the induction in the gap:

Figure 2 - Calculation mathematical model LIM without taking into account

winding distribution

(6)

The total electromagnetic power Sem, transmitted from the primary to the gap and SE, can be found as the flow of the normal Sy component of the Poynting vector through the surface y =

(7)

Where REm= ReSEm- active component, taking into account the mechanical power P2 and losses in the SE;

QEm= ImSEm- reactive component, takes into account the main magnetic flux and scattering in the gap;

WITH- complex, conjugations with WITH2 .

Traction force Fx and normal force Fat for LIM is determined based on the Maxwellian stress tensor.

(8)

(9)

To calculate a cylindrical LIM, one should set L = 2c, the number of harmonics along the transverse axis n = 0, i.e. in fact, the solution turns into a two-dimensional one, along X-Y coordinates. In addition, this technique allows one to correctly take into account the presence of a massive steel rotor, which is its advantage.

The procedure for calculating the characteristics at a constant value of current in the winding:

1. The traction force Fx(S) was calculated using formula (8);
2. mechanical power

R2 (S)=FX(S) ·= FX(S) 21 (1 – S); (10)

1. Electromagnetic power SEm(S) = PEm(S) + jQEm(S) was calculated according to the expression, formula (7)
2. Inductor copper loss

Rel.1= mI2 rf (11)

Where rf- active resistance of the phase winding;

1. efficiency without taking into account losses in the core steel

(12)

1. Power factor

(13)

where, is the impedance modulus of the series equivalent circuit (Fig. 2).

(14)

- leakage inductive reactance of the primary winding.

Thus, an algorithm for calculating the static characteristics of a LIM with a short-circuited secondary element has been obtained, which makes it possible to take into account the properties of the active parts of the structure at each tooth division.

The developed mathematical model allows:

• Apply a mathematical apparatus for calculating a cylindrical linear asynchronous motor, its static characteristics based on detailed equivalent circuits for electrical primary and secondary and magnetic circuits.
• To evaluate the influence of various parameters and designs of the secondary element on the traction and energy characteristics of a cylindrical linear induction motor.
• The results of the calculations make it possible to determine, as a first approximation, the optimal basic technical and economic data when designing cylindrical linear induction motors.

In the third chapter "Computational-theoretical research" the results of numerical calculations of the influence of various parameters and geometric dimensions on the energy and traction performance of the CLAD using the mathematical model described earlier.

The TsLAD inductor consists of individual washers located in a ferromagnetic cylinder. The geometric dimensions of the inductor washers, taken in the calculation, are shown in fig. 3. The number of washers and the length of the ferromagnetic cylinder are determined by the number of poles and the number of slots per pole and phase of the winding of the CLIM inductor.

The parameters of the inductor (geometry of the tooth layer, number of poles, pole division, length and width) were taken as independent variables, the parameters of the secondary structure were the type of winding, electrical conductivity G2 = 2 d2, as well as the parameters of the reverse magnetic circuit. The results of the study are presented in the form of graphs.

Figure 3 - Inductor device

1-Secondary element; 2-nut; 3-sealing washer; 4- coil;

5-engine housing; 6-winding, 7-washer.

For the circuit breaker drive being developed, the following are unambiguously defined:

1. Mode of operation, which can be characterized as "start". The operating time is less than a second (tv = 0.07 s), there may be repeated starts, but even in this case the total operating time does not exceed a second. Consequently, electromagnetic loads are a linear current load, the current density in the windings can be taken significantly higher than those accepted for steady-state electrical machines: A = (25 ... 50) 103 A / m; J = (4…7) A/mm2. Therefore, the thermal state of the machine can be ignored.
2. Stator winding supply voltage U1 = 380 V.
3. Required traction force Fx 1500 N. At the same time, the change in effort during operation should be minimal.
4. Strict dimensions restrictions: length Ls 400 mm; outer diameter of the stator D = 40…100 mm.
5. Energy indicators (, cos) do not matter.

Thus, the research task can be formulated as follows: for given dimensions, determine the electromagnetic loads, the value of the design parameters of the LIM, providing the necessary traction force in the interval 0,3 S 1 .

Based on the formed research task, the main indicator of LIM is the traction force in the slip interval 0,3 S 1 . In this case, the traction force largely depends on the design parameters (the number of poles 2p, air gap , non-magnetic cylinder thickness d2 and its electrical conductivity 2 , electrical conductivity 3 and magnetic permeability 3 of a steel rod that acts as a reverse magnetic circuit). For specific values ​​of these parameters, the traction force will be unambiguously determined by the linear current load of the inductor, which, in turn, at U = const depends on the arrangement of the tooth layer: number of slots per pole and phase q, the number of turns in the coil WTo and parallel branches a.

Thus, the LIM thrust force is represented by a functional dependence

FX= f(2р,, , d2 , 2 , 3 , 3 , q, Wk, A, a) (16)

Obviously, some of these parameters take only discrete values ​​( 2p,, q, Wk, a) and the number of these values ​​is insignificant. For example, the number of poles can only be considered 2p=4 or 2p=6; hence the very specific pole divisions = 400/4 = 100 mm and 400/6 = 66.6 mm; q = 1 or 2; a = 1, 2 or 3 and 4.

With an increase in the number of poles, the starting traction drops significantly. The drop in tractive effort is associated with a decrease in pole division and magnetic induction in the air gap B. Therefore, the optimal is 2p=4(Fig. 4).

Figure 4 - Traction characteristic of CLAD depending on the number of poles

Changing the air gap does not make sense, it should be minimal according to the operating conditions. In our version = 1 mm. However, in fig. 5 shows the dependence of the traction force on the air gap. They clearly show the drop in force with increasing clearance.

Figure 5 The traction characteristic of the CLA at various values ​​of the air gap ( =1.5mm and=2.0mm)

At the same time, the operating current increases I and reduced energy levels. Relatively freely varying remain only the electrical conductivity 2 , 3 and magnetic permeability 3 VE.

Change in the electrical conductivity of the steel cylinder 3 (Fig. 6) the traction force of the CLAD has an insignificant value up to 5%.

Figure 6

electrical conductivity of steel cylinder

The change in the magnetic permeability 3 of the steel cylinder (Fig. 7) does not bring significant changes in the traction force Fх=f(S). With a working slip S=0.3, the traction characteristics are the same. Starting traction force varies within 3…4%. Therefore, considering the insignificant influence 3 And 3 on the traction force of the CLA, the steel cylinder can be made of magnetically soft steel.

Figure 7 Traction characteristic of the CLA at different values Xmagnetic permeability (3 =1000 0 And 3 =500 0 ) steel cylinder

From the analysis of graphical dependencies (Fig. 5, Fig. 6, Fig. 7), the conclusion follows: changes in the conductivity of the steel cylinder and magnetic permeability, limiting the non-magnetic gap, it is impossible to achieve constancy of the traction force Fx due to their small influence.

Figure 8 Traction characteristic of the CLA at different values

electrical conductivity SE

Parameter with which you can achieve a constant tractive effort FX= f(2р,, , d2 , 2 , 3 , 3 , q, Wk, A, a) TSLAD, is the electrical conductivity of the 2 secondary element. Figure 8 shows the optimal extreme variants of conductivities. The experiments carried out on the experimental setup made it possible to determine the most appropriate specific conductivity within =0.8 107 …1.2 107 cm/m.

Figures 9…11 show dependencies F,Iat different values ​​of the number of turns in the winding coil of the CLIM inductor with a shielded secondary element ( d2 =1 mm; =1 mm).

Figure 9 Dependence I=f(S) for different values ​​of the number

turns in a coil

Figure 10. Addiction cos=f(S) Figure 11. Addiction= f(S)

The graphical dependences of the energy indicators on the number of turns in the bowls are the same. This suggests that a change in the number of turns in the coil does not lead to a significant change in these indicators. This is the reason for the lack of attention to them.

The increase in traction force (Fig. 12) as the number of turns in the coil decreases is explained by the fact that the wire cross section increases at constant values ​​of the geometric dimensions and the fill factor of the inductor slot with copper and a slight change in the current density value. The motor in the circuit breaker drives operates in the starting mode for less than a second. Therefore, to drive mechanisms with a large starting traction force and a short-term operation mode, it is more efficient to use a CLA with a small number of turns and a large cross-section of the wire of the inductor winding coil.

Figure 12. The traction characteristic of the CLIM for various values ​​of the number

stator coil turns

However, with frequent switching on of such mechanisms, it is necessary to have an engine heating reserve.

Thus, on the basis of the results of a numerical experiment using the above calculation method, it is possible to determine with a sufficient degree of accuracy the trend in the change in electrical and traction indicators for various variables of the CLIM. The main indicator for the constancy of traction is the electrical conductivity of the coating of the secondary element 2. Changing it within =0.8 107 …1.2 107 Cm / m, you can get the required traction characteristic.

Therefore, for the constancy of the CLIM thrust, it is sufficient to set the constant values 2p,, , 3 , 3 , q, A, a. Then, dependence (16) can be transformed into the expression

FX= f(K2 , Wk) (17)

Where K \u003d f (2p,, , d2 , 3 , 3 , q, A, a).

In the fourth chapter the method of carrying out the experiment of the studied method of the circuit breaker drive is described. Experimental studies of the characteristics of the drive were carried out on a VMP-10 high-voltage circuit breaker (Fig. 13).

Figure 13. Experimental setup.

Also in this chapter, the inertial resistance of the circuit breaker is determined, which is carried out using the methodology presented in the graph-analytical method, using kinematic diagram switch. The characteristics of elastic elements are determined. At the same time, the design of the oil circuit breaker includes several elastic elements that counteract the closing of the circuit breaker and allow you to accumulate energy to turn off the circuit breaker:

1. Acceleration springs FPU;
2. Release spring FBY;
3. Elastic forces generated by contact springs FKP.

The total effect of the springs, which oppose the force of the motor, can be described by the equation:

FOP(x)=FPU(x)+FBY(x)+FKP(X) (18)

The tensile force of a spring is generally described by the equation:

FPU=kx+F0 , (19)

Where k- coefficient of spring stiffness;

F0 - spring preload force.

For 2 accelerating springs, equation (19) has the form (without pretension):

FPU=2 kyx1 (20)

Where ky- coefficient of rigidity of the accelerating spring.

The force of the opening spring is described by the equation:

FBY=k0 x2 +F0 (21)

Where k0 - stiffness of the opening spring;

X1 , X2 - movement;

F0 - pretensioning force of the opening spring.

The force required to overcome the resistance of the contact springs, due to a slight change in the diameter of the socket, is assumed to be constant and equal to

FKP(x)=FKP (22)

Taking into account (20), (21), (22), equation (18) takes the form

FOP=kyx1 +k0 x2 +F0 +FKP (23)

The elastic forces generated by the opening, accelerating and contact springs are determined by studying the static characteristics of the oil circuit breaker.

FNavy=f(IN) (24)

To study the static characteristics of the switch, an installation was created (Fig. 13). A lever with a circle sector was made to eliminate the change in the length of the arm when the angle changes IN drive shaft. As a result, when the angle changes, the force application shoulder created by winch 1 remains constant.

L=f()=const (25)

To determine the coefficients of spring stiffness ky, k0 , the resistance forces of switching on the circuit breaker from each spring were investigated.

The study was conducted in the following sequence:

1. Study of the static characteristic in the presence of all springs z1 , z2 , z3 ;
2. Study of static characteristics in the presence of 2 springs z1 And z3 (accelerating springs);
3. Investigate static characteristics in the presence of one spring z2 (shutdown spring).
4. Investigate static characteristics in the presence of one accelerating spring z1 .
5. Investigate static characteristics in the presence of 2 springs z1 And z2 (accelerating and disconnecting springs).

Further, in the fourth chapter, the definition of electrodynamic characteristics is carried out. When short-circuit currents flow along the circuit of the circuit breaker, significant electrodynamic forces arise that interfere with switching on, significantly increase the load on the circuit breaker drive mechanism. Calculation of electrodynamic forces was carried out, which was carried out by graphic-analytical method.

The aerodynamic resistance of air and hydraulic insulating oil was also determined by the standard method.

In addition, the transfer characteristics of the circuit breaker are determined, which include:

1. Kinematic characteristic h=f(c);
2. Transfer characteristic of the circuit breaker shaft v=f(1);
3. Transfer characteristic of the traverse lever 1=f(2);
4. Transfer characteristic h=f(xT)

where in - the angle of rotation of the drive shaft;

1 - the angle of rotation of the circuit breaker shaft;

2 - the angle of rotation of the traverse lever.

In the fifth chapter an assessment of the technical and economic efficiency of using the CLCM in oil circuit breaker drives was carried out, which showed that the use of the CLCM-based oil circuit breaker drive makes it possible to increase their reliability by 2.4 times, reduce electricity consumption by 3.75 times, compared with the use of old drives. The expected annual economic effect from the introduction of CLAD in oil circuit breaker drives is 1063 rubles / off. with a payback period of capital investments in less than 2.5 years. The use of TsLAD will reduce the undersupply of electricity to rural consumers by 834 kWh per switch in 1 year, which will lead to an increase in the profitability of energy supply companies, which will amount to about 2 million rubles for the Udmurt Republic.

CONCLUSIONS

1. The optimal traction characteristic for the drive of oil circuit breakers has been determined, which makes it possible to develop the maximum traction force equal to 3150 N.
2. A mathematical model of a cylindrical linear induction motor based on a three-dimensional model is proposed, which makes it possible to take into account the edge effects of the magnetic field distribution.
3. A method is proposed for replacing an electromagnetic drive with a drive with a CLAD, which makes it possible to increase reliability by a factor of 2.7 and reduce the damage from undersupply of electricity by energy supply companies by 2 million rubles.
4. A physical model of the drive for oil circuit breakers of the VMP VMG type for a voltage of 6 ... 35 kV has been developed, and their mathematical descriptions have been given.
5. A pilot sample of the drive was developed and manufactured, which allows to implement the necessary parameters of the circuit breaker: closing speed 3.8 ... 4.2 m/s, switching off 3.5 m/s.
6. According to the research results, terms of reference and transferred to Bashkirenergo for the development of working design documentation for the revision of a number of low-oil circuit breakers of the VMP and VMG types.

Publications listed in the list of VAK and equated to them:

1. Bazhenov, V.A. Improvement of the high-voltage circuit breaker drive. / V.A. Bazhenov, I.R. Vladykin, A.P. Kolomiets//Electronic scientific and innovative journal "Engineering Bulletin of the Don" [Electronic resource]. - №1, 2012 pp. 2-3. – Access mode: http://www.ivdon.ru.

Other editions:

1. Pyastolov, A.A. Development of a drive for high-voltage circuit breakers 6…35 kV. /A.A. Pyastolov, I.N. Ramazanov, R.F. Yunusov, V.A. Bazhenov // Report on research work (art. No. GR 018600223428, inv. No. 02900034856. - Chelyabinsk: CHIMESH, 1990. - P. 89-90.
2. Yunusov, R.F. Development of a linear electric drive for agricultural purposes. / R.F. Yunusov, I.N. Ramazanov, V.V. Ivanitskaya, V.A. Bazhenov // XXXIII scientific conference. Abstracts of reports. - Sverdlovsk, 1990, pp. 32-33.
3. Pyastolov, A.A. High voltage oil circuit breaker drive. / Yunusov R.F., Ramazanov I.N., Bazhenov V.A.// Information leaflet No. 91-2. - TsNTI, Chelyabinsk, 1991. S. 3-4.
4. Pyastolov, A.A. Cylindrical linear asynchronous motor. / Yunusov R.F., Ramazanov I.N., Bazhenov V.A.// Information leaflet No. 91-3. - TsNTI, Chelyabinsk, 1991. p. 3-4.
5. Bazhenov, V.A. Choice of accumulative element for VMP-10 circuit breaker. Actual problems of agricultural mechanization: materials of the anniversary scientific and practical conference "Higher agroengineering education in Udmurtia - 50 years". / Izhevsk, 2005. S. 23-25.
6. Bazhenov, V.A. Development of an economical oil circuit breaker drive. Regional Scientific and Methodological Conference Izhevsk: FGOU VPO Izhevsk State Agricultural Academy, Izhevsk, 2004. P. 12-14.
7. Bazhenov, V.A. Improvement of the VMP-10 oil circuit breaker drive. Problems of Energy Development in Conditions of Industrial Transformations: Proceedings of the International Scientific and Practical Conference Dedicated to the 25th Anniversary of the Faculty of Electrification and Automation of Agriculture and the Department of Electrical Technology of Agricultural Production. Izhevsk 2003, pp. 249-250.

dissertations for the degree of candidate of technical sciences

Handed over to the set in 2012. Signed for publication on April 24, 2012.

Offset paper Headset Times New Roman Format 60x84/16.

Volume 1 print.l. Circulation 100 copies. Order No. 4187.

Publishing House of FGBOU VPO Izhevsk State Agricultural Academy Izhevsk, st. Student, 11

Specialty 05.09.03 - "Electrical complexes and systems"

Dissertations for the degree of candidate of technical sciences

Moscow - 2013 2

The work was done at the department of "Automated electric drive"

Federal State Budgetary Educational Institution of Higher Professional Education "National Research University "MPEI".

Scientific director: doctor of technical sciences, professor Masandilov Lev Borisovich

Official Opponents: Doctor of Technical Sciences, Professor of the Department of Electromechanics, Federal State Budgetary Educational Institution of Higher Professional Education NRU MPEI

Bespalov Victor Yakovlevich;

Candidate of Technical Sciences, Senior Researcher, Chief Specialist of "LiftAvtoService" branch of MGUP "MOSLIFT"

Chuprasov Vladimir Vasilievich

Lead organization: Federal State Unitary Enterprise "All-Russian Electrotechnical Institute named after V.I. Lenin"

The defense of the dissertation will take place on June 7, 2013 at 14:00. 00 min. in room M-611 at a meeting of the dissertation council D 212.157.02 at the Federal State Budgetary Educational Institution of Higher Professional Education "NRU MPEI" at the address: 111250, Moscow, Krasnokazarmennaya st., 13.

The dissertation can be found in the library of FGBOU VPO NRU MPEI.

Scientific secretary of the dissertation council D 212.157. Candidate of Technical Sciences, Associate Professor Tsyruk S.A.

GENERAL DESCRIPTION OF WORK

Relevance Topics.

40 - 50% of production mechanisms have working bodies with translational or reciprocating motion. Despite this, at present, rotary-type electric motors are most used in drives of such mechanisms, which require additional mechanical devices that convert rotational motion into translational motion: a crank mechanism, a screw and a nut, a gear and a rack, etc. In many cases, these devices are complex nodes of the kinematic chain, characterized by significant energy losses, which complicates and increases the cost of the drive.

The use in drives with translational movement of the working body instead of a motor with a rotating rotor of the corresponding linear analogue, which gives direct rectilinear motion, makes it possible to eliminate the transmission mechanism in the mechanical part of the electric drive. This solves the problem of maximum convergence of the source of mechanical energy - the electric motor and the actuator.

Examples of industrial machinery in which linear motors can currently be used are: hoisting machines, reciprocating motion devices such as pumps, switching devices, crane trolleys, elevator doors, etc.

Among linear motors, the simplest in design are linear induction motors (LAM), especially of cylindrical type (CLAM), which are the subject of many publications. Compared to rotating asynchronous motors (AM), CLIM are characterized by the following features: the openness of the magnetic circuit, which leads to the occurrence of longitudinal edge effects, and the significant complexity of the theory associated with the presence of edge effects.

The use of LIM in electric drives requires knowledge of their theory, which would make it possible to calculate both static modes and transient processes. However, to date, due to the noted features of their mathematical description has a very complex form, which leads to significant difficulties when it is necessary to carry out a number of calculations. Therefore, it is advisable to use simplified approaches to the analysis of the electromechanical properties of the LIM. Often, for calculations of electric drives with LIM, without evidence, a theory is used that is characteristic of conventional IM. In these cases, the calculations are often associated with significant errors.

For calculations of electromagnetic liquid-metal pumps Voldekom A.I. a theory based on the solution of Maxwell's equations was developed. This theory served as the basis for the emergence of various methods for calculating the static characteristics of the CLIM, among which one can single out the well-known method of analog modeling of multilayer structures.

However, this method does not allow calculating and analyzing dynamic modes, which is very important for electric drives.

Due to the fact that gearless electric drives with CLIM can be widely used in industry, their research and development are of considerable theoretical and practical interest.

The purpose of the dissertation work is the development of the theory of cylindrical linear induction motors using the method of analog modeling of multilayer structures and the application of this theory to the calculations of the static and dynamic characteristics of electric drives, as well as the development of a frequency-controlled gearless electric drive with a CLA for automatic doors widely used in industry.

To achieve this goal in the dissertation work, the following questions were set and solved. tasks:

1. The choice of the mathematical model of the CLIM and the development of a methodology for determining the generalized parameters of the CLIM corresponding to the chosen model, using which the calculations of the static and dynamic characteristics provide an acceptable agreement with the experiments.

2. Method development experimental definition CLAD parameters.

3. Analysis of application features and development of electric drives based on the systems FC-TSLAD and TPN-TSLAD for elevator doors.

4. Development of options for schemes of the gearless drive mechanism for sliding doors of an elevator car with a CLA.

Research methods. To solve the problems posed in the work, the following were used: the theory of the electric drive, the theoretical foundations of electrical engineering, the theory of electrical machines, in particular the method of analog modeling of multilayer structures, modeling and development by means of a personal computer in specialized programs Mathcad and Matlab, experimental laboratory studies.

The validity and reliability of scientific provisions and conclusions are confirmed by the results of experimental laboratory studies.

Scientific novelty work is as follows:

using the developed method for determining the generalized parameters of a low-speed CLIM, its mathematical description in the form of a system of equations is substantiated, which makes it possible to perform various calculations of the static and dynamic characteristics of an electric drive with a CLIM;

an algorithm for an experimental method for determining the parameters of an IM with a rotating rotor and a CLA is proposed, which is characterized by increased accuracy in processing the results of experiments;

as a result of studies of the dynamic properties of the CLAD, it was revealed that the transient processes in the CLAD are characterized by much less fluctuation than in the AD;

the use of CLAD for a gearless drive of elevator doors allows for simple operation in the FC–CLAD system, to form smooth processes of opening and closing doors.

The main practical result of the dissertation is as follows:

a method was developed for determining the generalized parameters of a low-speed CLIM, which makes it possible to carry out research and calculations during the operation and development of electric drives;

the results of the study of low-frequency CLIMs confirmed the possibility of minimizing the required power of the frequency converter when they are used in gearless electric drives, which improves the technical and economic performance of such electric drives;

the results of the study of the CLIM, connected to the network through a frequency converter, showed that the elevator door drive does not require a brake resistor and a brake switch, since the CLIM does not have a regenerative braking mode in the frequency zone used for the operation of the drive. The absence of a brake resistor and a brake key makes it possible to reduce the cost of the elevator door drive with the CLA;

for single-leaf and double-leaf sliding doors of the elevator cabin, a scheme of the gearless drive mechanism has been developed, which compares favorably with the use of a cylindrical linear asynchronous motor, characterized by the translational movement of the moving element, for the translational movement of the door leaves.

Approbation of work. Main results the work was discussed at the meetings of the Department of "Automated Electric Drive" NRU "MPEI", reported at the 16th international scientific and technical conference of students and graduate students "Radioelectronics, electrical engineering and energy" (Moscow, MPEI, 2010).

Publications. On the topic of the dissertation, six printed works were published, including 1 in publications recommended by the Higher Attestation Commission of the Russian Federation for the publication of the main results of dissertations for the scientific degrees of Doctor and Candidate of Sciences, and 1 patent for a utility model was received.

Structure and scope of work. The dissertation consists of an introduction, five chapters, general conclusions and a list of references. Number of pages - 146, illustrations - 71, number of references - 92 on 9 pages.

In the introduction the relevance of the topic of the dissertation work is substantiated, the purpose of the work is formulated.

In the first chapter the designs of the studied CLADs are presented. A method for calculating the static characteristics of the CLIM using the method of analog modeling of multilayer structures is described. The development of gearless drives for elevator car doors is considered. The features of existing electric drives of elevator doors are indicated, research tasks are set.

The method of analog modeling of multilayer structures is based on solving the system of Maxwell equations for various areas of linear induction motors. When obtaining the basic calculation formulas, the assumption is made that the inductor in the longitudinal direction is considered to be infinitely long (the longitudinal edge effect is not taken into account). Using this method, the static characteristics of the CLIM are determined by the formulas:

where d 2 is the outer diameter of the secondary element of the CLIM.

It should be noted that the calculations of the static characteristics of the CLIM using formulas (1) and (2) are cumbersome, since these formulas include variables that require a lot of intermediate calculations to determine.

For two CLIMs with the same geometric data, but a different number of turns wf of the inductor winding (CLIM 1 - 600, CLIM 2 - 1692), according to formulas (1) and (2), their mechanical and electromechanical characteristics were calculated at f1 50 Hz, U1 220 V The calculation results for CLAD 2 are shown in Figs. 1.

In our country, in most cases, unregulated electric drives with a relatively complex mechanical part with a relatively simple electrical part. The main disadvantages of such drives are the presence of a gearbox and a complex design of a mechanical device that converts rotational motion into translational, during which additional noise occurs.

In connection with the active development of converter technology, there has been a tendency to simplify the kinematics of mechanisms with a simultaneous complication of the electrical part of the drive through the use of frequency converters, with the help of which it became possible to form the desired door movement trajectories.

Thus, in recent years, adjustable electric drives have been used for doors of modern elevators, which provide almost silent, fast and smooth movement of doors. An example is a frequency-controlled door drive. Russian production with a control unit of the BUAD type and an asynchronous motor, the shaft of which is connected to the door mechanism through a V-belt drive. According to a number of specialists, the known adjustable drives, despite their advantages over unregulated ones, also have disadvantages associated with the presence of a belt drive and their relatively high cost.

In the second chapter a technique for determining the generalized parameters of the CLIM has been developed, with the help of which its mathematical description in the form of a system of equations is substantiated. The results of experimental studies of the static characteristics of the CLAP are presented. The characteristics of the CLIM with composite SEs are analyzed. The possibility of manufacturing low-frequency CLADS was studied.

The following approach to the study of an electric drive with a CLIM and its mathematical description is proposed:

1) we use the formulas (1) and (2) obtained using the method of analog modeling of multilayer structures for the static characteristics of the CLIM (mechanical and electromechanical) and calculate these characteristics (see Fig. 1);

2) on the obtained characteristics, we select two points, for which we fix the following variables: electromagnetic force, inductor current and complex phase resistance for one of these selected points (see Fig.

3) we believe that the static characteristics of the CLIM can also be described by formulas (5) and (6), which are given below and correspond to the steady state of a conventional asynchronous motor with a rotating rotor and are obtained from its differential equations;

4) we will try to find the generalized parameters included in the indicated formulas (5) and (6) of static characteristics using two selected points;

5) substituting the found generalized parameters into the indicated formulas (5) and (6), we fully calculate the static characteristics;

6) we compare the static characteristics found in paragraph and paragraph 5 (see Fig. 2). If these characteristics are close enough to each other, then it can be argued that the mathematical descriptions of CLAD (4) and AD have a similar form;

7) using the found generalized parameters, it is possible to write both the differential equations of the CLAD (4) and the formulas of various static characteristics that are more convenient for calculations following from them.

Rice. Fig. 1. Mechanical (a) and electromechanical (b) characteristics of the CLIM Approximate mathematical description of the CLIM, which is similar to the corresponding description of conventional IM, in vector form and in a synchronous coordinate system, has the following form:

Using the results of solving system (4) in steady-state conditions (at v / const), formulas for static characteristics are obtained:

To find the generalized parameters of the investigated CLIMs included in (5) and (6), it is proposed to apply the known method of experimental determination of the generalized parameters of the T-shaped equivalent circuit for an IM with a rotating rotor from the variables of two steady-state modes.

From expressions (5) and (6) it follows:

where k FI is a slip-independent coefficient. Writing relations of the form (7) for two arbitrary slips s1 and s2 and dividing them by each other, we obtain:

With known values ​​of electromagnetic forces and inductor currents for two slips, from (8) the generalized parameter r is determined:

With additionally known for one of the slips, for example s1, the value of the complex resistance Z f (s1) of the equivalent circuit of the CLAD, the formula for which can also be obtained as a result of solving system (4) in steady-state conditions, the generalized parameters and s are calculated as follows:

The values ​​of electromagnetic forces and currents of the inductor for two slips, as well as the complex resistance of the equivalent circuit for one of the slips, included in (9), (10) and (11), are proposed to be determined by the method of analog modeling of multilayer structures according to (1), (2 ) and (3).

Using the indicated formulas (9), (10) and (11), the generalized parameters of the CLIM 1 and CLIM 2 were calculated, with the help of which, further, using formulas (5) and (6) at f1 50 Hz, U1 220 V, their mechanical and electromechanical characteristics (for CLAD 2 are shown by curves 2 in Fig. 2). Also in fig. Figure 2 shows the static characteristics of the CLAD 2, determined by the method of analog modeling of multilayer structures (curves 1).

Rice. Fig. 2. Mechanical (a) and electromechanical (b) characteristics of the CLIM From the graphs in Figs. It can be seen from Fig. 2 that curves 1 and 2 practically coincide with each other, which means that the mathematical descriptions of CLIM and IM have a similar form. Therefore, in further studies, it is possible to use the obtained generalized CLIM parameters, as well as simpler and more convenient formulas for calculating the CLIM characteristics. The validity of using the proposed method for calculating the parameters of the CLIM was also additionally verified experimentally.

The possibility of manufacturing low-frequency CLADS, i.e. designed for increased voltage and made with an increased number of turns of the inductor winding. On fig. Figure 3 plots the static characteristics of the CLIM 1 (at f1 10 Hz, U1 55 V), the CLIM 2 (at f1 10 Hz, U1 87 V), and the low-frequency CLIM (at f1 10 Hz and U1 220 V, curves 3), which has the number of turns the inductor windings are 2.53 times larger than those of the TsLAD 2.

From those shown in Fig. 3 of the graphs shows that with the same mechanical characteristics of the considered CLIM in the first quadrant, the CLIM 2 has more than 3 times less inductor current than the CLIM 1, and the low-frequency CLIM has 2.5 times less than the CLIM 2. Thus, it turns out that the use of a low-frequency CLIM in a gearless electric drive allows minimizing the required power of the frequency converter, thereby improving the technical and economic performance of the electric drive.

1, Fig. Fig. 3. Mechanical (a) and electromechanical (b) characteristics of TsLAD 1, In the third chapter developed a method for experimental determination of the generalized parameters of the CLAP, which is implemented in a simple way at a stationary SE and allows you to determine the parameters of the CLIM, the geometrical data of which are unknown. The results of calculations of the generalized parameters of the CLIM and conventional IM using this method are presented.

In the experiment, the scheme of which is shown in Fig. 4, the motor windings (BP or TsLAD) are connected to a DC source. After closing the key K, the currents in the windings change in time from the initial value determined by the circuit parameters to zero. In this case, the dependence of the current in phase A on time is recorded using a current sensor DT and, for example, a specialized L-CARD L-791 board installed in a personal computer.

Rice. 4. Scheme of the experiment to determine the parameters of IM or CLIM As a result of mathematical transformations, a formula was obtained for the dependence of the current drop in the CLIM phase, which has the form:

where p1, p2 are constants related to the generalized parameters s, r and CLIM or AD as follows:

From formulas (12) and (13) it follows that the type of the transitional process of the decrease in the CLIM current depends only on the generalized parameters s, r and.

To determine the generalized parameters of the CLIM or IM according to the experimental current decay curve, it is proposed to single out three equidistant time points t1, t2 and t3 on it and fix the corresponding values ​​of the currents. In this case, taking into account (12) and (13), it becomes possible to compose a system of three algebraic equations with three unknowns - s, r and:

the solution of which is advisable to obtain numerically, for example, by the Levenberg-Marquardt method.

Experiments to determine the generalized parameters of IM and TsLAD were carried out for two engines: IM 5A90L6KU3 (1.1 kW) and TsLAD 2.

On fig. Figure 5 shows the theoretical and experimental curves for the decrease in the current of the CLIM 2.

Rice. Fig. 5. Current decay curves for CLIM 2: 1 – curve calculated from the generalized parameters obtained in the second chapter; 2 – curve calculated by generalized parameters, which are obtained as a result of their experimental determination CLAD.

The fourth chapter reveals the features of the nature of transient processes in the CLAD. An electric drive based on the FC–CLAD system for elevator doors has been developed and researched.

For a qualitative assessment of the characteristics of the nature of transient processes in the CLIM, a well-known method was used, which consists in the analysis of the attenuation coefficients characterizing the dependences of the IM variables with a rotating rotor at a constant speed.

The greatest influence on the rate of attenuation (oscillation) of transient processes of variables TsLAD or HELL has the smallest damping coefficient 1. In fig. Figure 6 shows the calculated dependences of the attenuation coefficients 1 on the electrical speed for two CLIMs (CLIM 1 and CLIM 2) and two IMs (4AA56V4U3 (180 W) and 4A71A4U3 (550 W)).

Rice. Fig. 6. Dependences of the lowest attenuation coefficient 1 for CLAD and IM. Figure 6 shows that the damping coefficients of the CLIM are practically independent of the speed, in contrast to the damping coefficients of the considered AM, for which 1 at zero speed is 5–10 times less than at nominal speed. It should also be noted that the values ​​of the attenuation coefficients 1 at low speeds for the two considered IMs are significantly lower than for the CLIM 1 (by 9–16 times) or the CLIM 2 (by 5–9 times). In connection with the foregoing, it can be assumed that real transient processes in CLAD are characterized by much less fluctuation than in IM.

To test the assumption made about the lower fluctuation of real transient processes in the CLIM compared to the IM, a number of numerical calculations of direct starts of the CLIM 2 and IM (550 W) were carried out. The obtained dependences of the moment, force, speed and current of the IM and CLIM on time, as well as the dynamic mechanical characteristics, confirm the previously stated assumption that the transient processes of the IM are characterized by much less oscillation than that of the IM, due to a significant difference in their lowest damping coefficients ( Fig. 6). At the same time, the dynamic mechanical characteristics of the CLIM differ less from the static ones than for the IM with a rotating rotor.

For a typical elevator (with an opening of 800 mm), the possibility of using a low-frequency CLAD as a drive motor for the elevator door mechanism was analyzed. According to experts, for typical elevators with an opening width of 800 mm, static forces when opening and closing doors differ from each other: when opening they are about 30 - 40 N, and when closing - about 0 - 10 N. the transient processes of the CLIM have significantly less fluctuations compared to the IM, the implementation of the movement of the door leaves with the help of the low-frequency CLIM by switching to the corresponding mechanical characteristics, according to which the CLIM accelerates or decelerates to a given speed, is considered.

In accordance with the selected mechanical characteristics of the low-frequency CLAD, the calculation of its transient processes was carried out. It is assumed in the calculations that the total mass of the electric drive, determined by the masses of the CE TsLAD and the doors of the cabin and shaft of a typical elevator (with an opening of 800 mm), is 100 kg. The resulting graphs of transient processes are shown in fig. 7.

Rice. Fig. 7. Transient processes of the low-frequency CLIM during opening (a, c, e) Characteristic P provides acceleration of the drive to a steady speed of 0.2 m/s, and characteristic T provides braking from a steady speed to zero. The considered variant of the control of the CLIM for opening and closing the doors shows that the use of the CLIM for the door drive has a number of advantages (smooth transients with relatively simple control; the absence of additional devices that convert rotational motion into translational, etc.) compared to the use of conventional IM and therefore of considerable interest.

The elevator car door drive with conventional IM or CLAD, as noted above, is characterized by different resistance forces when opening and closing the doors. At the same time, the drive electric machine can operate both in motor and brake modes in the process of opening and closing the elevator doors. In the dissertation, an analysis was made of the possibility of energy transfer to the network during the operation of the CLA in braking modes.

It is shown that CLAD 2 has no regenerative braking mode at all in a wide frequency range. A formula is given for determining the cut-off frequency, below which there is no generator mode with the return of electricity to the network at the IM and TsLAD. The conducted studies of the energy modes of operation of the CLR allow us to draw an important conclusion: when using the CLR connected to the network through a frequency converter, a brake resistor and a brake switch are not required to drive the elevator doors. The absence of a brake resistor and a brake key makes it possible to reduce the cost of driving the elevator doors with the CLAD.

The fifth chapter provides an overview of existing elevator door drives.

Variants of schemes of the gearless drive mechanism for sliding elevator doors with CLAD have been developed.

For single-leaf and double-leaf sliding doors of the elevator car, it is proposed to use the developed gearless drive with CLAD. A diagram of the mechanism of such a drive in the case of single-leaf doors is shown in fig. 8, a, in the case of double doors - in fig. 8, b.

Rice. Fig. 8. Schemes of the drive mechanism of the sliding single-leaf (a) and double-leaf (b) doors of the elevator cabin with the CLIM: 1 - CLIM, 2 - CLIM inductor, 3 - secondary element of the CLIM, 4 - reference ruler, 5, 6 - door leaves, 7, 8 - blocks of the cable system, Proposed technical solutions make it possible to create gearless drives for sliding single-leaf or double-leaf doors, in particular, elevator cabins, which are characterized by high technical and economic indicators, as well as reliable and inexpensive operation when using a simple and relatively inexpensive cylindrical linear electric motor with the translational movement of a moving element to form the translational movement of the door leaves.

A patent for utility model No. 127056 has been obtained for the proposed options for gearless drives of single-leaf and double-leaf sliding doors with CLAD.

GENERAL CONCLUSIONS

1. A technique has been developed for determining the generalized parameters included in the differential equations of the CLAD, which is based on calculations using the method of analog modeling of multilayer structures and the method for determining the BP variables from the indicators of its two steady-state modes.

2. Using the developed method for determining the generalized parameters of a low-speed CLIM, its mathematical description in the form of a system of equations is substantiated, which makes it possible to perform various calculations of the static and dynamic characteristics of an electric drive with a CLIM.

3. The use of a low-frequency CLIM in a gearless electric drive allows minimizing the required power of the frequency converter, which improves the technical and economic performance of the electric drive.

4. A method for the experimental determination of the generalized parameters of the CLAD is proposed, which is characterized by an increased accuracy in processing the results of experiments.

5. The use of CLAD for a gearless drive of elevator doors allows, with simple control in the FC–CLAD system, to form smooth processes of opening and closing doors. To implement the desired processes, it is necessary to use a relatively inexpensive frequency converter with a minimum set of required functionality.

6. When using the CLCM connected to the network via a frequency converter, the elevator door drive does not require a brake resistor and a brake chopper, since the CRCM does not have a regenerative braking mode in the frequency zone used for the operation of the drive. The absence of a brake resistor and a brake key makes it possible to reduce the cost of driving the elevator doors with the CLAD.

7. For single-leaf and double-leaf sliding doors, mainly for the elevator car, a gearless drive mechanism has been developed, which compares favorably with the use of a cylindrical linear asynchronous motor, characterized by the translational movement of the moving element, to carry out the translational movement of the door leaves. A patent for utility model No. 127056 has been obtained for the proposed options for gearless drives of single-leaf and double-leaf sliding doors with CLAD.

1. Masandilov L.B., Novikov S.E., Kuraev N.M. Features of determining the parameters of an asynchronous motor with frequency control.

// Bulletin of MPEI, No. 2. - M.: MPEI Publishing House, 2011. - S. 54-60.

2. Utility model patent No. 127056. Masandilov L.B., Kuraev N.M., Fumm G.Ya., Zholudev I.S. Elevator cabin sliding door drive (options) // BI No. 11, 2013.

3. Masandilov L.B., Kuraev N.M. Features of the choice of design parameters of an asynchronous motor with frequency control // Electric drive and control systems // Proceedings of MPEI. Issue. 683. - M.: MPEI Publishing House, 2007. - S. 24-30.

4. Masandilov L.B., Kuraev N.M. Calculation of parameters of the T-shaped equivalent circuit and characteristics of cylindrical linear asynchronous motors // Electric drive and control systems // Proceedings of MPEI. Issue. 687. - M.: MPEI Publishing House, 2011. - S. 14-26.

5. Masandilov L.B., Kuzikov S.V., Kuraev N.M. Calculation of the parameters of equivalent circuits and characteristics of cylindrical linear asynchronous and MHD motors // Electric drive and control systems // Proceedings of MPEI.

Issue. 688. - M.: MPEI Publishing House, 2012. - S. 4-16.

6. Baidakov O.V., Kuraev N.M. Modernization of the electric drive according to the TVC-AD system with quasi-frequency control // Radioelectronics, electrical engineering and energy: Sixteenth Intern. scientific-technical conf. students and graduate students: Proceedings. report In 3 volumes. T. 2. M .: MPEI Publishing House, 2010.

Similar works:

"Kotin Denis Alekseevich ADAPTIVE ALGORITHMS OF SENSORLESS VECTOR CONTROL OF ASYNCHRONOUS ELECTRIC DRIVES OF LIFTING AND TRANSPORT MECHANISMS Specialty: 05.09.03 - Electrical complexes and systems ABSTRACT of the dissertation for the degree of candidate of technical sciences Novosibirsk - 2010 of Technical Sciences, Professor Pankratov Vladimir Vyacheslavovich ... "

« complexes and systems ABSTRACT of the dissertation for the degree of candidate of technical sciences Moscow - 2010 The work was done at the Department of Theoretical Electrical Engineering of the Moscow Aviation Institute (National Research University in the field of aviation, rocket and space systems) MAI. Scientific..."

"KAMALOV Filyus Aslyamovich ELECTRICAL COMPLEX WITH A CONDUCTIVE MAGNETO-HYDRODYNAMIC CONVERTER WITH A CONIC CHANNEL (RESEARCH AND DEVELOPMENT) Specialty: 05.09.03 - Electrical complexes and systems AUTHOR'S ABSTRACT of the dissertation for the degree of candidate of technical sciences Ufa - 2013 Technical University. Supervisor: Doctor of Technical Sciences,...»

«TYURIN Maksim Vladimirovich IMPROVING THE EFFICIENCY OF GEARLESS ELECTROMECHANICAL POWER STEERING OF A CAR Specialty: 05.09.03 – Electrical complexes and systems ABSTRACT of the dissertation for the degree of candidate of technical sciences NOVOSIBIRSK - 2009 candidate..."

Stotskaya Anastasia Dmitrievna DEVELOPMENT AND RESEARCH OF THE ROTOR POSITION CONTROL SYSTEM IN ELECTROMAGNETIC SUSPENSION Specialty: 05.09.03 – Electrical complexes and systems ABSTRACT of the dissertation for the degree of candidate of technical sciences St. Petersburg - 2013 2 The work was done at the St. Petersburg State Electrotechnical University LETI named after . IN AND. Ulyanov (Lenin), at the Department of Systems automatic control Scientific adviser:..."

«TOLKACHEVA KSENIA PETROVNA RESEARCH OF ENERGY EFFICIENCY OF OUTDOOR LIGHTING INSTALLATIONS WHEN DESIGNING USING LASER SCANNING Specialty 05.09.07 – Light engineering Abstract of the dissertation for the degree of candidate of technical sciences Saransk 2013 ..."

«Kuznetsov Andrey Vladimirovich RESEARCH AND DEVELOPMENT OF ADAPTIVE REGULATORS OF ELECTROHYDRAULIC STEERING SYSTEMS Specialty: 05.09.03 – Electrical complexes and systems ABSTRACT of the dissertation for the degree of candidate of technical sciences St. Petersburg - 2011 The work was done at St. Petersburg State Electrotechnical University LETI im. IN AND. Ulyanova (Lenina) Supervisor - Doctor of Technical Sciences, Professor N. D. Polyakhov ... "

«Kazmin Evgeniy Viktorovich CALCULATION AND OPTIMIZATION OF MAGNETOELECTRIC MACHINES WITH RADIAL PM ON THE ROTOR SURFACE Specialty 05.09.01 – Electromechanics and electrical apparatus ABSTRACT of the dissertation for the degree of candidate of technical sciences Moscow – 2009 2 The work was done at the Department of Electromechanics of the Moscow Power Engineering Institute (Technical University ). Scientific supervisor doctor of technical sciences, professor Ivanov-Smolensky Alexey...»

«Emelyanov Oleg Anatolyevich WORKABILITY OF METAL FILM CAPACITORS IN FORCED ELECTRIC HEAT MODES Specialty 05.09.02 – Electrical materials and products Abstract of the dissertation for the degree of candidate of technical sciences St. Petersburg 2004 The work was done in the State educational institution of higher professional education St. Petersburg State Polytechnic University Scientific supervisors : doctor..."

“Grigoryev Alexander Vasilievich Development and study of options for managing the state of electric drives based on asynchronous electric motors specialty 05.09.03 - electrical complexes and abstract systems of the dissertation for the degree of candidate of technical sciences Kemerovo - 2010 2 Work was completed in the state educational institution of higher professional education Kuzbass State Technical University Scientific adviser -..."

«Tikhomirov Ilya Sergeevich COMPLEX OF INDUCTION HEATING WITH IMPROVED ENERGY PERFORMANCES Specialty: 05.09.03 - Electrical complexes and systems Abstract of the dissertation for the degree of candidate of technical sciences St. Petersburg - 2009 2 The work was done at the St. Petersburg State Electrotechnical University. IN AND. Ulyanova (Lenina) Supervisor - Honored Worker of Science and Technology of the RSFSR, Doctor of Technical Sciences, ... "

"Shutov Kirill Alekseevich DEVELOPMENT OF MANUFACTURING TECHNOLOGY AND RESEARCH OF SUPERCONDUCTING POWER CABLES BASED ON HIGH-TEMPERATURE SUPERCONDUCTORS OF THE FIRST GENERATION specialty 05.09.02 - Electrical materials and products research, design and technology institute...»

«KUCHER EKATERINA SERGEEVNA RESEARCH OF IDENTIFICATION ALGORITHMS FOR SYSTEMS OF SENSORLESS VECTOR CONTROL OF ASYNCHRONOUS ELECTRIC DRIVES Specialty: 05.09.03 – Electrical complexes and systems ABSTRACT of the dissertation for the degree of candidate of technical sciences Novosibirsk – 2012 ..."

Kolovsky Aleksey Vladimirovich Synthesis of control systems for an automated excavator electric drive using sliding modes. Specialty 05.09.03 - Electrotechnical complexes and systems (technical sciences and) Abstract of the dissertation for the degree of candidate of technical sciences Tomsk 2012 1 The work was done at the Khakass Technical Institute - a branch of the Federal State Autonomous Educational Institution of Higher Professional Education Siberian Federal University Supervisor doctor of technical sciences, professor, ... »

«SHISHKOV Kirill Sergeevich DEVELOPMENT AND RESEARCH OF ASYNCHRONOUS ELECTRIC DRIVE MECHANISMS OF FORMATION OF WATER SHAFTS Specialty: 05.09.03 – Electrical complexes and systems Abstract of the dissertation for the degree of candidate of technical sciences Ivanovo – 2014 The work was done in the federal state budgetary educational institution of higher professional education Ivanovo State Energy named after V. I. Lenin ... "

“Vasiliev Bogdan Yuryevich Structure and effective algorithms for managing the frequency-regulating electric drive of the centrifugal super-capture of the gas-skitting unit specialty 05.09.03-electrical complexes and systems of the dissertation for the scientific degree of candidate of technical sciences of St. Petersburg-2013 Work was completed in the Federal State Budget Educational Institution of Higher Professional Professional Professional Education National...»

«Gorozhankin Aleksey Nikolaevich VALVE ELECTRIC DRIVE WITH SYNCHRONOUS REACTIVE ENGINE OF INDEPENDENT EXCITATION Specialty 05.09.03 – Electrical complexes and systems Abstract of dissertation for the degree of Candidate of Technical Sciences Chelyabinsk 2010 The work was done at the Department of Electric Drive and Automation of Industrial Installations of South Ural State University. Supervisor - Doctor of Technical Sciences, Professor Yury Usynin ... "

«IVANOV Mikhail Alekseevich MODELING AND SEARCH FOR A RATIONAL DESIGN OF A CONTACTLESS MOTOR WITH EXCITATION FROM PERMANENT MAGNETS Specialty: 05.09.01 – Electromechanics and electrical devices ABSTRACT of the dissertation for the degree of candidate of technical sciences Voronezh - 2012 The work was done at the Voronezh State Technical University Head Doctor of Technical Sciences, Associate Professor Annenkov Andrey Nikolaevich Official opponents...»

«BALAGULA Yuri Moiseevich APPLICATION OF FRACTAL ANALYSIS IN THE PROBLEMS OF ELECTRICAL ENGINEERING Specialty: 05.09.05 – Theoretical electrical engineering ABSTRACT of the dissertation for the degree of candidate of technical sciences St. Petersburg – 2013 doctor of technical sciences, professor head:...»

«KUBAREV Vasiliy Anatolyevich SYSTEM OF LOGICAL CONTROL OF AN AUTOMATED ELECTRIC DRIVE OF A MINING LIFTING INSTALLATION 05.09.03 – Electrical complexes and systems ABSTRACT of the dissertation for the degree of candidate of technical sciences Novokuznetsk - 2013 , doctor..."

In 2010 Mitsubishi's NA series EDM machines were equipped with cylindrical linear motors for the first time, surpassing all similar solutions in this area.

Compared to ball screws, they have a much greater margin of durability and reliability, are capable of positioning with higher accuracy, and also have better dynamic characteristics. In other configurations of linear motors, CLDs benefit from overall design optimization: less heat generation, higher economic efficiency, ease of installation, maintenance and operation.

Considering all the advantages that CLD have, it would seem, why else be smart with the drive part of the equipment? However, not everything is so simple, and a separate, isolated, point improvement will never be as effective as updating the entire system of interconnected elements.

Mitsubishi Electric MV1200R Y-Axis Drive

Therefore, the use of cylindrical linear motors has not remained the only innovation implemented in the drive system of Mitsubishi Electric EDM machines. One of the key transformations that made it possible to take full advantage of the advantages and potential of the CLD to achieve unique indicators of accuracy and equipment productivity was a complete modernization of the drive control system. And, unlike the engine itself, the time has already come for the implementation of our own developments.

Mitsubishi Electric is one of the world's largest manufacturers of CNC systems, the vast majority of which are made directly in Japan. At the same time, the Mitsubishi Corporation includes a huge number of research institutes conducting research, including in the field of drive control systems and CNC systems. It is not surprising that the company's machines have almost all the electronic filling of their own production. Thus, they implement modern solutions that are maximally adapted to a specific line of equipment (of course, it is much easier to do this with your own products than with purchased components), and at the lowest price, maximum quality, reliability and performance are provided.

A striking example of the practical application of our own developments was the creation of a system ODS— Optical drive system. The NA and MV series of machines were the first to use cylindrical linear motors in feed drives controlled by third generation servo amplifiers.

Mitsubishi NA and MV machines are equipped with the first of its kind Optic Drive System

A key feature of Mitsubishi servo amplifiers of the family MelServoJ3 is the ability to communicate using the protocol SSCNET III: the connection of motors, feedback sensors through amplifiers with the CNC system occurs via fiber optic communication channels.

At the same time, the data exchange rate increases almost 10 times (compared to systems of previous generations of machine tools): from 5.6 Mbps to 50 Mbps.

Due to this, the duration of the information exchange cycle is reduced by 4 times: from 1.77 ms to 0.44 ms. Thus, the control of the current position, the issuance of corrective signals occurs 4 times more often - up to 2270 times per second! Therefore, the movement occurs more smoothly, and its trajectory is as close as possible to the given one (this is especially important when moving along complex curvilinear trajectories).

In addition, the use of fiber optic cables and servo amplifiers operating under the SSCNET III protocol can significantly increase noise immunity (see figure) and reliability of information exchange. In the event that the incoming pulse contains incorrect information (the result of interference), then it will not be processed by the engine, instead the data of the next pulse will be used. Since the total number of pulses is 4 times greater, such a omission of one of them minimally affects the accuracy of movement.

As a result, the new drive control system, thanks to the use of third-generation servo amplifiers and fiber optic communication channels, provides more reliable and 4 times faster communication, which makes it possible to achieve the most accurate positioning. But in practice, these advantages are not always useful, since the control object itself - the engine, due to its dynamic characteristics, is not able to process control pulses of such a frequency.

That is why the most justified is the combination of servo amplifiers j3 with cylindrical linear motors in a single ODS system used in machines of the NA and MV series. The CLD, due to its excellent dynamic properties - the ability to work out huge and small accelerations, move stably at high and low speeds, has a huge potential for improving positioning accuracy, which the new control system helps to realize. The motor handles high-frequency control pulses with ease, providing precise and smooth movement.

Mitsubishi machines allow you to get parts with outstanding accuracy and roughness. Guarantee for positioning accuracy - 10 years.

However, the benefits of an EDM equipped with an ODS system are not limited to improved positioning accuracy. The fact is that obtaining a part with a certain accuracy and roughness on an electroerosive machine is achieved by moving the electrode (wire) at a certain speed along the trajectory and in the presence of a certain voltage and distance between the electrodes (wire and workpiece). Feed, voltage and electrode spacing are strictly defined for each material, cutting height and desired roughness. However, the processing conditions are not strictly defined, just as the material of the workpiece is not homogeneous, therefore, in order to obtain a suitable part with the specified characteristics, it is necessary that at each particular moment in time the processing parameters change in accordance with changes in the processing conditions. This is especially important when it comes to obtaining micron accuracy and high roughness values. It is also extremely necessary to ensure the stability of the process (the wire should not break, there should not be significant jumps in the magnitude of the movement speed).

processing monitor. in green shows a speed graph that shows how adaptive control works

This problem is solved with the help of adaptive control. The machine adapts itself to changing processing conditions by changing the feed rate and voltage. How quickly and correctly these corrections are made depends on how accurately and quickly the workpiece will turn out. Thus, the quality of the adaptive control to a certain extent determines the quality of the machine itself through its accuracy and productivity. And it is here that the advantages of using the CLD and the ODS system as a whole are fully manifested. The ability of ODS to ensure the processing of control pulses with the highest frequency and accuracy has made it possible to improve the quality of adaptive control by an order of magnitude. Now the processing parameters are adjusted up to 4 times more often, moreover, the overall positioning accuracy is also higher.

Carbide, height 60 mm, roughness Ra 0.12, max. the error is 2 µm. The part was obtained on a Mitsubishi NA1200 machine

Summing up, we can say that the use of CLD in Mitsubishi Electric machines would not have been such an effective step, allowing to reach new heights of both accuracy and processing productivity without the introduction of an updated control system.

Only complex, but, nevertheless, fully justified and proven changes in the design can be the key to improving the quality (as an aggregate indicator of the level of reliability and technological capabilities of the equipment) and the competitiveness of the machine. Changes for the Better is Mitsubishi's motto.

Dissertation abstract on this topic ""

As a manuscript

BAZHENOV VLADIMIR ARKADIEVICH

CYLINDRICAL LINEAR ASYNCHRONOUS MOTOR IN THE DRIVE OF HIGH-VOLTAGE SWITCHES

Specialty 05.20.02 - electrical technology and electrical equipment in agriculture

dissertations for the degree of candidate of technical sciences

Izhevsk 2012

The work was carried out at the Federal State Budgetary Educational Institution of Higher Professional Development "Izhevsk State Agricultural Academy" (FGBOU VIO Izhevsk State Agricultural Academy)

Scientific adviser: candidate of technical sciences, associate professor

1 at Vladykin Ivan Revovich

Official opponents: Viktor Vorobyov

doctor of technical sciences, professor

FGBOU VPO MGAU

them. V.P. Goryachkina

Bekmachev Alexander Egorovich Candidate of Technical Sciences, Project Manager of Radiant-Elcom CJSC

Lead organization:

Federal State Budgetary Educational Institution of Higher Professio cal I Education "Chuvash State Agricultural Academy" (FGOU VPO Chuvash State Agricultural Academy)

Protection will take place on May 28, 2012 at 10 o'clock at a meeting of the dissertation council KM 220.030.02 at the Izhevsk State Agricultural Academy at the address: 426069,

Izhevsk, st. Student, 11, room. 2.

The dissertation can be found in the library of the FGBOU VPO Izhevsk State Agricultural Academy.

Posted on the site: tuyul^vba/gi

Scientific Secretary of the Dissertation Council

UFO. Litvinyuk

GENERAL DESCRIPTION OF WORK

Nosg integrated automation of rural electrical systems "

Sulimov M.I., Gusev B.C. marked ™ ^

actions of relay protection and automation /rchaGIV Z0 ... 35% of cases

creative state driveGHthan up to TsJTJ™

share of VM 10 ... 35 kV s, nv ", m "n mv"; Defects account for

N.M., Palyuga M^AaSTZ^rZZr^Tsy

re-enabling GAPSH "°TKa30V astoma™che-

drive as a whole

■ PP-67 PP-67K

■VMP-10P KRUN K-13

"VMPP-YUP KRUN K-37

Figure I - Analysis of failures in electric drives BM 6 .. 35 kV VIA, they consume a lot of power and require installation of a bulky

shutdown mechanism failure, r.u.

00" PP-67 PP-67

■ VMP-10P KRU| K-13

■ VMPP-YUP KRUN K-37 PE-11

- "„, „“, and a charger or a rectifier unit-battery 3 ^ DD ° 0rMTs0M with a power of 100 kVA. By virtue of the

Roystva with "n ^ ^ prnvo" about found wide application.

3ashyunaRGbsh ^ "carry out an ™ and" from the merits of "nedospshyuv various leads-

dovdlyaVM. „„_,.,* DC drives: not possible

Disadvantages el.sgromap ^ ^ ^ ^ including the electromagnetism of the adjustment SK0R ° ^ DH ^ ^ el ^ ^.apnpv, which increases Sh1Ta> large "inductiveness" of the winding I from the floor.

turn-on time of the switch

lator battery or - "P- ^ / ™ th area up to 70 m> and DR-large dimensions and weight, that of alternating current: large

The disadvantages of ^^^^^^^ "connecting wires,

¡yyyy-^5^-speed-and

T-D "Disadvantages of induction drive

b ^ ^ "GGZH cylindrical lines-The above shortcomings * "structural features"

"b, x asynchronous engines" Therefore, we propose to use them in

and weight and size "O ^ 3 ^" "110 ^ 0 * e_ \ for oil switches as a power element in the pr " ^ Rostekhiadzor's deadline for

lei, which, according to the data of West-Ur^sko^ companies in

Udmurt Republic VMG-35 300 pieces.

operation "^^^^^ the following goal was determined Pa Based on the above high-voltage oil switches, the increase in efficiency, "P ^ ^ ^ allowing to reduce the damage of 6.35 kV chalets operating on the basis of CLAD, allows

"Firs were delivered following an analysis of existing designs of drives

3" theoretical and characteristics

GrHGb ^ C - "- - "" 6-35 *

basis of CLAD.

6. Conduct a feasibility study. .

use of TsLAD for drives of oil circuit breakers 6...35 kV.

The object of the study is: a cylindrical linear asynchronous electric motor (CLAM) for driving devices of switches of rural distribution networks 6 ... 35 kV.

Subject of study: study of the traction characteristics of the CLIM when operating in oil circuit breakers 6 ... 35 kV.

Research methods. Theoretical studies were carried out using the basic laws of geometry, trigonometry, mechanics, differential and integral calculus. Natural studies were carried out with the VMP-10 switch using technical and measuring tools. The experimental data were processed using the Microsoft Excel program. Scientific novelty of the work.

1. A new type of oil circuit breaker drive is proposed, which makes it possible to increase the reliability of their operation by 2.4 times.

2. A technique has been developed for calculating the characteristics of the CLIM, which, unlike those proposed earlier, allows one to take into account the edge effects of the magnetic field distribution.

3. The main design parameters and modes of operation of the drive for the VMP-10 circuit breaker are substantiated, which reduce the undersupply of electricity to consumers.

The practical value of the work is determined by the following main results:

1. The design of the VMP-10 circuit breaker drive is proposed.

2. A method for calculating the parameters of a cylindrical linear induction motor has been developed.

3. A technique and a program for calculating the drive have been developed, which allow calculating the drives of switches of similar designs.

4. The parameters of the proposed drive for VMP-10 and the like have been determined.

5. A laboratory sample of the drive was developed and tested, which made it possible to reduce the loss of power supply interruptions.

Implementation of research results. The work was carried out in accordance with the R&D plan of FGBOU VPO CHIMESH, registration number No. 02900034856 "Development of a drive for high-voltage circuit breakers 6 ... 35 kV". The results of the work and recommendations are accepted and used in the Production Association "Bashkirenergo" S-VES (an act of implementation has been received).

The work is based on a generalization of the results of studies carried out independently and in collaboration with scientists from the Chelyabinsk State Agricultural University (Chelyabinsk), the Izhevsk State Agricultural Academy.

The following provisions have been defended:

1. Type of oil circuit breaker drive based on CLAD

2. Mathematical model for calculating the characteristics of the CLIM, as well as the traction

force depending on the design of the groove.

drive calculation program for VMG, VMP circuit breakers with voltage 10...35 kV. 4. Results of studies of the proposed design of the oil circuit breaker drive based on the CLA.

Approbation of research results. The main provisions of the work were reported and discussed at the following scientific and practical conferences: XXXIII scientific conference dedicated to the 50th anniversary of the Institute, Sverdlovsk (1990); international scientific-practical conference "Problems of Energy Development in the Conditions of Industrial Transformations" (Izhevsk, Izhevsk State Agricultural Academy, 2003); Regional Scientific and Methodological Conference (Izhevsk, Izhevsk State Agricultural Academy, 2004); Actual problems of agricultural mechanization: materials of the anniversary scientific and practical conference "Higher agroengineering education in Udmurtia - 50 years". (Izhevsk, 2005), at the annual scientific and technical conferences of teachers and staff of the Izhevsk State Agricultural Academy.

Publications on the topic of dissertation. The results of theoretical and experimental studies are reflected in 8 printed works, including: in one article published in a journal recommended by the Higher Attestation Commission, two deposited reports.

Structure and scope of work. The dissertation consists of an introduction, five chapters, general conclusions and applications, presented on 167 pages of the main text, contains 82 figures, 23 tables and a list of references from 105 titles and 4 applications.

In the introduction, the relevance of the work is substantiated, the state of the issue, the purpose and objectives of the research are considered, and the main provisions submitted for defense are formulated.

The first chapter analyzes the designs of circuit breaker drives.

Installed:

The fundamental advantage of combining the drive with the CLA;

Need for further research;

Goals and objectives of the dissertation work.

In the second chapter, methods for calculating the CLIM are considered.

Based on the analysis of the propagation of the magnetic field, a three-dimensional model was chosen.

The winding of the CLIM in the general case consists of individual coils connected in series in a three-phase circuit.

We consider a CLA with a single-layer winding and a symmetrical arrangement of the secondary element in the gap with respect to the inductor core.

The following assumptions were made: 1. The current of the winding laid over a length of 2pm is concentrated in infinitely thin current layers located on the ferromagnetic surfaces of the inductor and creates a purely sinusoidal traveling wave. The amplitude is related by a known relationship with the linear current density and current load

creates a pure sinusoidal traveling wave. The amplitude is related by a known relationship with the linear current density and current load

to """d.""*. (1)

t - pole; w - number of phases; W is the number of turns in the phase; I - effective current value; P is the number of pairs of poles; J is the current density;

Ko6| - winding coefficient of the fundamental harmonic.

2. The primary field in the region of the frontal parts is approximated by the exponential function

/(") = 0.83 exp ~~~ (2)

The reliability of such an approximation to the real picture of the field is indicated by previous studies, as well as experiments on the LIM model. In this case, it is possible to replace L-2 with.

3. The beginning of the fixed coordinate system x, y, z is located at the beginning of the wound part of the incoming edge of the inductor (Fig. 2).

With the accepted formulation of the problem, n.s. windings can be represented as a double Fourier series:

where, A is the linear current load of the inductor; Kob - winding coefficient; L is the width of the reactive bus; C is the total length of the inductor; a - shear angle;

z \u003d 0.5L - a - zone of induction change; n is the order of the harmonic along the transverse axis; v is the order of harmonics along the longitudinal main;

We find the solution for the vector magnetic potential of the currents A In the air gap area, Ar satisfies the following equations:

divAs = 0.J(4)

For the VE equation A 2, the equations have the form:

DA2 .= GgM 2 cIU T2 = 0.

Equations (4) and (5) are solved by the method of separation of variables. To simplify the problem, we give only the expression for the normal component of the induction in the gap:

hell [KY<л

y 2a V 1st<ЬК0.51.

_¿1-2s-1-1"

Figure 2 - Calculation mathematical model of LIM without winding distribution

KP2. SOB---AH

X (sILu + C^Ly) exp y

The total electromagnetic power 83M transmitted from the primary to z" opTvE, Xer can be found as the flow of the normal 8 component of the Poynting vector through the surface y - 5

= / / yauzhs =

" - - \shXS + S2sILd\2

^ GrLs ^ GvVeG "" "S0STASH1YaSCHAYA" U ™ "*" "" mechanical power-

R™so "zR™"SHYA S°FASTELING"LEACHES THE FLOW „

C\ is a complex of conjugations with C2.

"z-or,", g ".msha" "mode"". ..z

II "in e., brss

^ I O L V o_£ V y

- " "\shXS + C.chaz?"

""-^/H^n^m-^gI

l " \shXS +S2s1gL5^

in terms of the coordinate L-Ukrome r r^r in two-dimensional, in terms of

chie steel ^torus^to^^^i

2) Mechanical power

Electromagnetic power £,., "1 \u003d p / c" + .y, / C1 " 1 "

according to the expression, formula (7) was calculated according to

4) Losses in copper inductor

Р,г1 = ШI1 Гф ^

where rf is the active resistance of the phase winding;

5) Efficiency without taking into account losses in the core steel

„ r.-i ■ (12) P, R „(5> + L, ..

6) Power factor

r m!\rr+rf) ^ typh1 m1 Z £

where, 2 = + x1 is the absolute impedance of the series

equivalent circuits (Figure 2).

x1=xn+xa1 O4)

v-yazi-g (15)

x \u003d x + x + x + Xa - leakage inductive reactance of the primary ob-p a * h

Thus, an algorithm for calculating the static characteristics of an LIM with a short-circuited secondary element was obtained, which makes it possible to take into account the properties of the active parts of the structure at each tooth division.

The developed mathematical model allows: . Apply a mathematical apparatus for calculating a cylindrical linear asynchronous motor, its static characteristics based on a variety of equivalent circuits for electrical primary and secondary and magnetic circuits

To evaluate the influence of various parameters and designs of the secondary element on the traction and energy characteristics of a cylindrical linear induction motor. . The results of the calculations make it possible to determine, as a first approximation, the optimal basic technical and economic data when designing cylindrical linear induction motors.

The third chapter "Computational and theoretical studies" presents the results of numerical calculations of the influence of various parameters and geometric parameters on the energy and traction performance of the CLIM using the mathematical model described earlier.

The TsLAD inductor consists of individual washers located in a ferromagnetic cylinder. The geometric dimensions of the inductor washers, taken in the calculation, are given in fig. 3. The number of washers and the length of the ferromagnetic cylinder - Гя "by the number of poles and the number of slots per pole and the phase of the winding of the inductor windings, electrical conductivity C2 - Ug L, and

as well as the parameters of the reverse magnetic circuit. The results of the study are presented in the form of graphs.

Figure 3 - Inductor device 1-Secondary element; 2-nut; З-sealing washer; 4- coil; 5-engine housing; 6-winding, 7-washer.

For the circuit breaker drive being developed, the following are unambiguously defined:

1 Mode of operation, which can be characterized as "start". The "work time" is less than a second (t. = 0.07 s), there may be restarts, but even in

In this case, the total operating time does not exceed a second. Therefore, electromagnetic loads are a linear current load, the current density in the windings can be taken to be significantly higher than those accepted for j steady state electrical machines: A = (25 ... 50) 10 A / m, J (4 ... /) A / mm2. Therefore, the thermal state of the machine can be ignored.

3. Required traction force Fn > 1500 N. In this case, the change in force during operation should be minimal.

4. Severe size restrictions: length Ls. 400 mm; outer diameter of the stator D = 40... 100 mm.

5 Energy values ​​(l, coscp) are irrelevant.

Thus, the task of research can be formulated as follows: for given dimensions, determine the electromagnetic loads, the value of the design parameters of the LIM, providing

dimmable traction force in the range of 0.3

Based on the formed research task, the main indicator of LIM is the traction force in the slip interval of 0.3

Thus, the LIM thrust force appears to be a functional dependence.

Fx = f(2p, r, &d2, y2, Yi, Ms > H< Wk, A, a) U<>>

tameters, some pr-t -ko and t \u003d 400/4 \u003d 100 - * 66.6 mmh

Tractive force drops significantly 5

TRACTION ° EFFORT ASSOCIATED WITH A decrease in pole division t and magnetic induction in air And division t

is 2p=4 (Fig. 4). °3Air gap Therefore, the optimal

OD 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0 9

Slide B, ooh

Figure 4 - Traction characteristic of the TsLAD "depending on the number of poles

3000 2500 2000 1500 1000 500 0 ■

1.5|at 2.0l<

0 0.10.20.30.40.50.60.70.80.9 1

FIGURE5YUK5, azo.

ra(6=1.5mm and 5=2.0mm)

conductivity y2, y3 and magnetic permeability ts3 VE.

The change in the electrical conductivity of the steel cylinder "(Fig. 6) on the traction force of the CLAD has an insignificant value of up to 5%.

0 0,10,23,30,40,50,60,70,83,91

Slide 8, ooh

Figure 6. Traction characteristic of the CLA at different values ​​of the electrical conductivity of the steel cylinder

A change in the magnetic permeability u3 of a steel cylinder (Fig. 7) does not bring significant changes in the traction force Px = DB). With a working slip of 8=0.3, the traction characteristics are the same. Starting traction force varies within 3...4%. Therefore, taking into account the insignificant influence of bonds and Mz on the traction force of the CLA, the steel cylinder can be made of magnetically soft steel.

0 0 1 0 2 0.3 0.4 0.5 0.6 0.7 0.8 0.9

Figure 7. Traction characteristic of the CDIM at various values ​​of magnetic permeability (Ts = 1000tso and Ts = 500tso) of a steel cylinder

From the analysis of graphical dependencies (Fig. 5, Fig. 6, Fig. 7), the conclusion follows: changes in the conductivity of the steel cylinder and magnetic permeability, limiting the non-magnetic gap, it is impossible to achieve a constant traction force 1 "X due to their small influence.

y=1.2-10"S/m

y=3 10"S/m

O 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 Slip E, o

Figure 8. Traction characteristic of the CLIM for various values ​​of the electrical conductivity of the SE

The parameter with which you can achieve the constancy of the traction force = / (2p, r,<$ й2 ,у2, уз, цз, Я, А, а) ЦЛАД, является удельная электропроводимость у2 вторичного элемента. На рисунке 8 указаны оптимальные крайние варианты проводимостей. Эксперименты, проведенные на экспериментальной установке, позволили определить наиболее подходящую удельную проводимость в пределах у=0,8-10"...1,2-ю"См/м.

Figures 9...11 show the dependencies Г, I, t), oo$<р = /(я) при различных значениях числа витков в катушке обмотки индуктора ЦЛАД с экранированным вторичным э л е м е нто в (с/,=1 мм; 5=1 мм).

Lg az o* ~05 Ob d5 To

Figure 9. Dependence 1=G(8) for different values ​​of the number of turns in the coil

Figure 10. Dependency eos

Drawing! I Dependence t]= f(S)

Graphical dependences of energy indicators on the number of turns in the bowls are the same. This suggests that a change in the number of turns in the coil does not lead to a significant change in these indicators. This is the reason for the lack of attention to them.

The increase in tractive effort (Fig. 12) as the number of turns in the coil decreases is explained by the fact. that the wire cross section increases at constant values ​​of the geometric dimensions and the fill factor of the inductor slot with copper and a slight change in the value of the current density. The motor in the circuit breaker drives operates in the starting mode for less than a second. Therefore, to drive mechanisms with a large starting traction force and a short-term operation mode, it is more efficient to use a CLA with a small number of turns and a large cross-section of the wire of the inductor winding coil.

they say / "4a? /? (/," ■ W0O 8oo boa íoo 2 os ■

O o/ O.3 oi 05 O 07 os ¿J? That

Figure 12. Traction characteristic of the CLIM for various values ​​of the number of turns era of the mountain coil

However, with frequent switching on of such mechanisms, it is necessary to have an engine heating reserve.

Thus, on the basis of the results of a numerical experiment using the above calculation method, it is possible to determine with a sufficient degree of accuracy the trend in the change in electrical and traction indicators for various variables of the CLIM. The main indicator for the constancy of traction force is the electrical conductivity of the coating of the secondary element y2. By changing it in the range y=0.8-10 ... 1.2-10 S/m, you can get the required traction characteristic.

Consequently, for the constancy of the thrust of the CLIM, it is sufficient to set the constant values ​​2p, m, s, y),

! ],=/(K y2, \Uk) (17)

where K \u003d / (2p, m, 8, L2, y, Z »

The fourth chapter describes the methodology for conducting the experiment of the investigated method of the circuit breaker drive. Experimental studies of the characteristics of the drive were carried out on a high-voltage circuit breaker VMP-10 (Fig. 13)

Figure 13 Experimental setup.

Also in this chapter, the inertial resistance of the circuit breaker is determined, which is carried out using the technique presented in the graph-analytical method, using the kinematic diagram of the circuit breaker. The characteristics of elastic elements are determined. At the same time, the design of the oil circuit breaker includes several elastic elements that counteract the closing of the circuit breaker and allow you to accumulate energy to turn off the circuit breaker:

1) GPU acceleration springs",

2) Spring release G on",

31 Elastic forces created by contact springs Pk. - №1, 2012 pp. 2-3. - Access mode: http://w\v\v.ivdon.ru.

Other editions:

2. Pyastolov, A.A. Development of a drive for high-voltage circuit breakers 6...35 kV." /A.A. Pyastolov, I.N. No. 02900034856.-Chelyabinsk: CHIMESH.1990. - S. 89-90.

3. Yunusov, R.F. Development of a linear electric drive for agricultural purposes. / R.F. Yunusov, I.N. Ramazanov, V.V. Ivanitskaya, V.A. Bazhenov // XXXIII scientific conference. Abstracts of reports. - Sverdlovsk, 1990, pp. 32-33.

4. Pyastolov, A.A. High voltage oil circuit breaker drive. / Yunusov R.F., Ramazanov I.N., Bazhenov V.A. // Information leaflet No. 91-2. -TsNTI, Chelyabinsk, 1991. S. 3-4.

5. Pyastolov, A.A. Cylindrical linear asynchronous motor. / Yunusov R.F., Ramazanov I.N., Bazhenov V.A. // Information leaflet No. 91-3. -TsNTI, Chelyabinsk, 1991. p. 3-4.

6. Bazhenov, V.A. Choice of accumulative element for VMP-10 circuit breaker. Actual problems of agricultural mechanization: materials of the anniversary scientific and practical conference "Higher agroengineering education in Udmurtia - 50 years". / Izhevsk, 2005. S. 23-25.

7. Bazhenov, V.A. Development of an economical oil circuit breaker drive. Regional Scientific and Methodological Conference Izhevsk: FGOU VPO Izhevsk State Agricultural Academy, Izhevsk, 2004. P. 12-14.

8. Bazhenov, V.A. Improvement of the VMP-10 oil circuit breaker drive. Problems of Energy Development in Conditions of Industrial Transformations: Proceedings of the International Scientific and Practical Conference Dedicated to the 25th Anniversary of the Faculty of Electrification and Automation of Agriculture and the Department of Electrical Technology of Agricultural Production. Izhevsk 2003, pp. 249-250.

dissertations for the degree of candidate of technical sciences

Handed over to the set_2012. Signed for publication on April 24, 2012.

Offset paper Typeface Times New Roman Format 60x84/16. Volume I print.l. Circulation 100 copies. Order No. 4187. Publishing house FGBOU BIIO Izhevsk State Agricultural Academy Izhevsk, st. Student. eleven

Text of the work Bazhenov, Vladimir Arkadievich, dissertation on the topic of Electrical technology and electrical equipment in agriculture

FEDERAL STATE BUDGETARY EDUCATIONAL INSTITUTION OF HIGHER PROFESSIONAL EDUCATION "IZHEVSK STATE AGRICULTURAL ACADEMY"

As a manuscript

Bazhenov Vladimir Arkadievich

CYLINDRICAL LINEAR ASYNCHRONOUS MOTOR IN THE DRIVE OF HIGH-VOLTAGE SWITCHES

Specialty 05.20.02 Electrical technologies and electrical equipment in agriculture

THE DISSERT for the degree of candidate of technical sciences

Scientific adviser: candidate of technical sciences,

Vladykin Ivan Revovich

Izhevsk - 2012

At various stages of research, the work was carried out under the guidance of Doctor of Technical Sciences, Professor, Head. Department of "Electric Machines" of the Chelyabinsk Institute of Mechanization and Electrification of Agriculture A.A. Pyastolova (chapter 1, 4, 5) and Doctor of Technical Sciences, professors, head. Department of "Electric drive and electrical machines" of St. Petersburg State Agrarian University A.P. Epifanova (Chapter 2, 3), The author expresses his sincere gratitude.

INTRODUCTION .................................................. ................................................. ....................................5

1 ANALYSIS OF OIL CIRCUIT CIRCUIT ACTUATORS AND THEIR CHARACTERISTICS .................................................................. ................................................. ...............................................7

1.1 The device and principle of operation of the switches .............................................. ......eleven

1.2 Classification of drives............................................... .....................................14

1.3 Main components of the drive....................................................... ................................19

1.4 General design requirements for actuators............................................................... ..22

1.5 Electromagnetic drives............................................................... ................................................26

1.5.1 Designs of electromagnetic actuators.................................................... .......28

1.5.2 AC solenoid drive .............................................................. .42

1.5.3 Drive based on flat LIM.................................................................. .........................45

1.5.4 Circuit breaker drive based on a rotating asynchronous motor .................................................................. ................................................. ...............................48

1.5.5 Drive based on cylindrical linear asynchronous

engine ................................................. ................................................. .......................50

CONCLUSIONS ON THE CHAPTER AND OBJECTIVES OF THE WORK .............................................. ...............................52

2 CALCULATION OF THE CHARACTERISTICS OF LINEAR ASYNCHRONOUS MOTOR GAGELS.................................................................. ................................................. ...............................................55

2.1 Analysis of methods for calculating the characteristics of the LIM .............................................. .......55

2.2 Methodology based on one-dimensional theory ............................................... ......................56

2.3 Technique based on two-dimensional theory .......................................................... ...............58

2.4 Technique based on a three-dimensional model ............................................................... ...............59

2.5 Mathematical model of a cylindrical induction motor on

the basis of the equivalent circuit .............................................................. ...................................................65

CONCLUSIONS ON THE CHAPTER .............................................. ................................................. .................94

3 COMPUTATIONAL AND THEORETICAL INVESTIGATIONS.................................................................. ......95

3.1 General provisions and tasks to be solved (problem statement) .............................................. 95

3.2. Investigated indicators and parameters .............................................. .......................96

CONCLUSIONS ON THE CHAPTER .............................................. ................................................. .............105

4 EXPERIMENTAL STUDIES .............................................................. ...........106

4.1 Determining the inertial resistance of the BM-drive system .............................106

4.2 Determination of the characteristics of elastic elements...............................................................110

4.3 Determination of electrodynamic characteristics....................................................114

4.4 Determination of aerodynamic air resistance and

hydraulic insulating oil BM...................................................... .................117

CONCLUSIONS ON THE CHAPTER .............................................. ................................................. ..............121

5 TECHNICAL AND ECONOMIC INDICATORS.................................................................. ........122

CONCLUSIONS ON THE CHAPTER .............................................. ................................................. ..............124

GENERAL CONCLUSIONS AND RESEARCH RESULTS..................................................................125

LITERATURE................................................. ................................................. .........................126

APPENDIX A................................................... ................................................. ...................137

APPENDIX B CALCULATION OF RELIABILITY INDICATORS OF DRIVES VM6...35KV...139

APPENDIX B REFERENCE ON THE RESEARCH OF THE DEVELOPMENT OBJECT .................................142

I Patent documentation .................................................................. ................................................142

II Scientific and technical literature and technical documentation .........................................143

III Technical characteristics of a cylindrical linear asynchronous motor .............................................................. ................................................. ......................144

IV Analysis of operational reliability of VM-6... .35kV drives......................145

V Design features of the main types of drives VM-6... 35 kV........150

APPENDIX D................................................... ................................................. ....................156

An example of a specific implementation of the drive .............................................................. .................156

high voltage circuit breaker .................................................................. ...................................156

Calculation of the power consumed by the inertial drive.......................................................162

during the power-on operation .................................................................. ................................................162

Index of main symbols and abbreviations .................................................................. .........165

INTRODUCTION

With the transfer of agricultural production to an industrial basis, the requirements for the level of reliability of power supply are significantly increased.

The target complex program for improving the reliability of power supply to agricultural consumers /TsKP PN/ provides for the widespread introduction of automation equipment for rural distribution networks of 0.4.. .35 kV, as one of the most effective ways to achieve this goal. The program includes, in particular, equipping distribution networks with modern switching equipment and drive devices for them. Along with this, it is planned to widely use, especially at the first stage, the primary switching equipment in operation.

The most widely used in rural networks are oil circuit breakers (VM) with spring and spring-load drives. However, it is known from operating experience that VM drives are one of the least reliable elements of switchgear. This reduces the efficiency of complex automation of rural electrical networks. For example, in it is noted that 30 ... 35% of cases of relay protection and automation / RZA / are not implemented due to the unsatisfactory condition of the drives. Moreover, up to 85% of defects fall on the share of VM 10 ... 35 kV with spring-load drives. According to the work data, 59.3% of failures of automatic reclosing /AR/ based on spring drives occur due to the auxiliary contacts of the drive and the circuit breaker, 28.9% due to the mechanisms for turning on the drive and keeping it in the on position. The unsatisfactory state and the need for modernization and the development of reliable drives are noted in the works.

There is a positive experience in the use of more reliable electromagnetic DC drives for 10 kV VMs at step-down substations for agricultural purposes. However, due to a number of features, these drives have not found wide application [53].

The purpose of this stage of research is to choose the direction of research.

In the process of work, the following tasks were solved:

Determination of reliability indicators of the main types of drives VM-6.. .35 kV and their functional units;

Analysis of design features of various types of drives VM-6...35 kV;

Substantiation and selection of a constructive solution for the VM drive 6...35 kV and areas of research.

1 ANALYSIS OF OIL CIRCUIT ACTUATORS AND THEIR CHARACTERISTICS

The operation of the drive of oil circuit breakers 6 - 10 kV largely depends on the perfection of the design. Design features are determined by the requirements for them:

The power consumed by the drive during the operation of turning on the VM must be limited, because power is supplied from low-power auxiliary transformers. This requirement is especially significant for step-down substations of agricultural power supply.

The oil circuit breaker drive must provide sufficient switching speed,

Remote and local control,

Normal operation at acceptable levels of change in operating voltages, etc.

Based on these requirements, the main drive mechanisms are made in the form of mechanical converters with a different number of stages (stages) of amplification, which, in the process of switching off and on, consume little power to control the large flow of energy consumed by the switch.

In the known drives, amplification cascades are structurally implemented in the form of locking devices (ZUO, ZUV) with latches, reducing mechanisms (RM) with multi-link breaking levers, as well as mechanical amplifiers (MU) using the energy of a lifted load or a compressed spring. Figures 2 and 3 (Appendix B) show simplified diagrams of oil circuit breaker drives of various types. Arrows and numbers above them show the direction and sequence of interaction of mechanisms in the process of work.

The main switching devices at substations are oil and oil-free switches, disconnectors, fuses up to 1000 V and above, automatic switches, knife switches. In electrical networks of low power with a voltage of 6-10 kV, the simplest switching devices are installed - load switches.

In switchgear 6 ... 10 kV, in withdrawable switchgear, low-oil pendant switches with built-in spring or electromagnetic drives (VMPP, VMPE) are often used: Rated currents of these switches: 630 A, 1000 A, 1600 A, 3200 A.

Breaking current 20 and 31.5 kA. This range of designs makes it possible to use VMP circuit breakers both in electrical installations of medium power, and on large input lines and on the side of the secondary circuits of relatively large transformers. Execution for current 31.5 kA allows the use of VMP compact circuit breakers in high-power networks 6... .10 kV without reacting and thereby reduce voltage fluctuations and deviations in these networks.

VMG-10 low-oil pot switches with spring and electromagnetic drives are manufactured for rated currents of 630 and 1000 A and a short-circuit breaking current of 20 kA. They are built into stationary chambers of the KSO-272 series and are mainly used in medium-power electrical installations. Low-oil circuit breakers of the VMM-10 type of low power are also produced with built-in spring drives for a rated current of 400 A and a rated breaking current of 10 kA.

In a wide range of designs and parameters, the following types of electromagnetic switches are manufactured: VEM-6 with built-in electromagnetic drives for a voltage of 6 kV, rated currents of 2000 and 3200 A, rated breaking current of 38.5 and 40 kA;

VEM-10 with built-in electromagnetic drive, voltage 10 kV, rated currents 1000 and 1250, rated breaking current 12.5 and 20 kA;

VE-10 with built-in spring drives, voltage 10 kV, rated currents 1250, 1600, 2500, 3000 A. Rated breaking currents 20 and 31.5 kA.

According to their parameters, electromagnetic circuit breakers correspond to VMP low-oil circuit breakers and have the same scope. They are suitable for frequent switching operations. The switching capacity of the circuit breakers depends on the type of drive, its design and reliability of operation. At substations of industrial enterprises, spring and electromagnetic drives built into the circuit breaker are mainly used. Electromagnetic drives are used in critical installations:

When supplying power consumers of the first and second categories with frequent switch operations;

Particularly responsible electrical installations of the first category, regardless of the frequency of operations;

In the presence of a rechargeable battery.

For substations of industrial enterprises, complete large-block devices are used: KRU, KSO, KTP of various capacities, voltages and purposes. Complete devices with all devices, measuring instruments and auxiliary devices are manufactured, assembled and tested at the factory or in a workshop and delivered assembled to the installation site. This gives a great economic effect, as it speeds up and reduces the cost of construction and installation and allows you to work using industrial methods. Complete switchgears have two fundamentally different designs: withdrawable (KRU series) and stationary (KRU series)

KSO, KRUN, etc.). Devices of both types are equally successful in solving the problems of electrical installation and maintenance work.

Roll-out switchgears are more convenient, reliable and safe in operation. This is achieved due to the protection of all current-carrying parts and contact connections with reliable insulation, as well as the ability to quickly replace the circuit breaker by rolling out and servicing in the workshop. The location of the switch drive is such that its external inspection can be carried out both with the switch on and with the switch off without rolling out the latter.

The plants manufacture unified series of withdrawable switchgear for indoor installation for voltage up to 10 kV, the main technical parameters of which are given in Table 1.

Table 1.1 - Main parameters of switchgear for voltage 3-10 kV for indoor installation

Series Rated voltage, in kV Rated current, in A Type of oil circuit breaker Drive type

KRU2-10-20UZ 3.6, 10 630 1000 1600 2000 2500 3200 Low oil pot VMP-Yuld PE-11 PP67 PP70

KR-10-31, 5UZ 6.10 630 1000 1600 3200 Low oil pot

KR-10D10UZ 10 1000 2000 4000 5000 Low oil pot

KE-10-20UZ 10 630 1000 1600 2000 3200 Electromagnetic

KE-10-31, 5UZ 10 630 1000 Electromagnetic

1.1 The device and principle of operation of the switches

VMG-10-20 type circuit breakers are three-pole high-voltage circuit breakers with a small volume of arc extinguishing liquid (transformer oil). The switch is intended for switching high-voltage AC circuits with a voltage of 10 kV in the normal mode of operation of the installation, as well as for automatically disconnecting these circuits in case of short-circuit currents and overloads that occur during abnormal and emergency operating modes of the installations.

The principle of operation of the circuit breaker is based on extinguishing the electric arc that occurs when the contacts are opened, by the flow of the gas-oil mixture resulting from the intensive decomposition of transformer oil under the action of the high temperature of the arc. This flow receives a certain direction in a special arc quenching device located in the arc burning zone.

The circuit breaker is controlled by drives. At the same time, operational switching on is carried out due to the energy of the drive, and switching off - due to the energy of the opening springs of the circuit breaker itself.

The design of the switch is shown in Fig. 1.1. Three poles of the switch are mounted on a common welded frame 3, which is the base of the switch and has holes for mounting the switch. On the front side of the frame, there are six porcelain insulators 2 (two per pole), which have an internal elastic mechanical fastening. On each pair of insulators, the pole of the switch 1 is suspended.

The drive mechanism of the circuit breaker (Fig. 9) consists of a shaft 6 with levers 5 welded to it. Tripping springs 1 are attached to the outer levers 5, a buffer spring 2 is connected to the middle one. Insulating levers are mechanically fixed at the opposite ends of the levers, which are connected to current-carrying contact rods 9 with the help

shchi earrings 7 and serve to transfer movement from the switch shaft to the contact rod.

installation (type VMP-10) - general view

Between the extreme and middle levers on the switch shaft, a pair of two-arm levers 4 with rollers at the ends is welded. These levers serve to limit the on and off positions of the circuit breaker. When turned on, one of the rollers approaches the bolt 8, when turned off, the second roller moves the oil buffer rod 3; a more detailed arrangement of which is shown in Fig.1. 2.

Depending on the kinematics of the cubicle, the circuit breaker allows the middle or side connection of the drive. Lever 13 (Fig. 1.1) is used for medium connection of the drive, lever 12 (Fig. 1.1) is additionally installed on the circuit breaker shaft for side connection.

Figure 1.2 - Switch pole

The main part of the switch pole (Fig. 1.2) is cylinder 1. For switches with a rated current of 1000A, these cylinders are made of brass. Cylinders of switches for rated current 630A are made of steel and have a longitudinal non-magnetic seam. Two brackets are welded to each cylinder for attaching it to the support insulators, and a casing 10 with an oil filler plug 11 and an oil indicator 15. The casing serves as an additional

Investigation of the influence of non-sinusoidality of the supply voltage, due to pulse-width modulation, on the energy characteristics of asynchronous motors

• • Technologies and means of agricultural mechanization
  • Electrical technologies and electrical equipment in agriculture
  • Technologies and means of maintenance in agriculture

480 rub. | 150 UAH | $7.5 ", MOUSEOFF, FGCOLOR, "#FFFFCC",BGCOLOR, "#393939");" onMouseOut="return nd();"> Thesis - 480 rubles, shipping 10 minutes 24 hours a day, seven days a week and holidays

Ryzhkov Alexander Viktorovich Analysis and choice of rational designs of a cylindrical linear motor with magnetoelectric excitation: dissertation... candidate of technical sciences: 05.09.01 / Ryzhkov Alexander Viktorovich; [Place of protection: Voronezh. state tech. un-t].- Voronezh, 2008.- 154 p.: ill. RSL OD, 61 09-5/404

Introduction

Chapter 1 Analysis of theoretical and constructive directions of development of electric machines of linear movement 12

1.1 Specific features of design implementations of linear electric machines 12

1.2 Analysis of the developed design of a cylindrical linear electric motor 26

1.3 Overview of Linear Machine Design Practices 31

1.4 Modeling of electromagnetic processes based on the finite element method 38

1.5 The purpose of the work and the objectives of the study 41

Chapter 2 Electromagnetic Calculation Algorithm for Contactless Cylindrical Linear DC Motor 43

2.1 Statement of the problem 43

2.2 Analysis of a cylindrical linear DC motor with a longitudinal - radial design of the magnetic system 45

2.3 Algorithm for electromagnetic calculation of a cylindrical linear DC motor 48

2.4 Evaluation of the thermal state of a cylindrical linear motor 62

Chapter 3 Simulation and selection of rational sets of output parameters of a cylindrical linear DC motor 64

3.1 Linear synthesis cylindrical engine direct current based on the criteria for maximum specific traction, energy performance 64

3.2 Finite Element Modeling of a Cylindrical Linear DC Motor 69

3.2.1 Description of input data for modeling 69

3.2.2 Analysis of simulation results 78

Chapter 4 Practical implementation and results of experimental studies of cylindrical linear motors 90

4.1 Model samples of cylindrical linear DC motors 90

4.1.1 Structural components of the linear motor architecture 90

4.1.2 Model implementation of cylindrical linear motors 95

4.1.3 Cylindrical control unit structure linear electric motor 96

4.2 Results of experimental studies of the developed variants of cylindrical linear electric motors 100

4.2.1 Investigation of the thermal state of a linear motor 101

4.2.2 Experimental studies of induction in the gap of prototypes of linear motors 103

4.2.3 Investigations of the electromagnetic traction holding force against the current in the winding 107

4.2.3 Study of the dependence of the traction force of the developed linear electric motors on the amount of displacement of the moving part 110

4.2.3 Mechanical characteristics developed samples of linear motors 118

Findings 119

Conclusion 120

References 122

Appendix A 134

Appendix B 144

Annex B 145

Introduction to work

Relevance of the topic.

Currently, cylindrical linear motors are becoming more common as actuators for electric drives. special purpose implemented within the framework of electrical complexes used, in particular, in space and medical technology. At the same time, the presence of a direct direct action of the executive body in cylindrical linear motors determines their advantage over flat linear motors. This is due to the absence of one-sided attraction forces, as well as the lower inertia of the moving part, which determines their high dynamic qualities.

It should be noted that in the field of developing tools for analyzing design options for linear motors, there are positive results obtained both by domestic ones (Voldek A.I., Svecharnik D.V., Veselovsky O.N., Konyaev A.Yu., Sarapulov F.N. ) and foreign researchers (Yamamura, Wang J., Jewell Geraint W., Howe D.). However, these results cannot be considered as the basis for creating universal tools that allow choosing the optimal design options for linear electric motors in relation to a specific object area. This necessitates additional research in the field of designing special linear motors of cylindrical architecture in order to obtain rational design options that are object-oriented.

Thus, based on the foregoing, the relevance of the research topic is dictated by the need for additional research aimed at developing tools for modeling and analyzing cylindrical linear motors with magnetoelectric excitation in order to obtain rational design solutions.

The subject of the dissertation research corresponds to one of the main scientific directions of VPO "Voronezh State Technical University" Computing systems and software and hardware electrical complexes (Development and research of intelligent and information technologies for designing and managing complex industrial complexes and systems. GB NIR No. 2007.18).

Purpose and objectives of the study. The aim of the work is to create a set of tools for analyzing the designs of cylindrical linear DC motors with magnetoelectric excitation, allowing the choice of their rational options, focused on use in the framework of special-purpose electric drives, realizing the limiting values ​​of specific energy indicators and the level of dynamic properties.

In accordance with this goal, the following tasks were set and solved in the work:

analysis of rational designs of cylindrical linear DC motors, which provide, within the framework of special-purpose electric drives, the limiting values ​​of specific energy indicators;

carrying out theoretical studies of the processes occurring in linear non-contact DC motors as the basis for constructing an algorithm for the electromagnetic calculation of a cylindrical linear electric motor;

development of an electromagnetic calculation algorithm, taking into account the features caused by the architecture of the magnetic systems of a cylindrical linear motor;

development of structures of finite element models for the analysis of electromagnetic processes in relation to the conditions of a cylindrical linear motor;

Conducting experimental studies of prototypes, under
confirming the adequacy of analytical models and the developed algorithm
MA Design Cylindrical Linear Motors.

Research methods. IN The work used methods of field theory, theory of electrical circuits, theory of design of electrical machines, computational mathematics, physical experiment.

Scientific novelty. The following results, which are distinguished by scientific novelty, were obtained in the work:

the design of the magnetic circuit of a cylindrical linear DC motor with axially magnetized permanent magnets as part of a magnetic system with a radial direction of magnetization, characterized by a new architecture for the construction of the moving part of a linear electric motor;

an algorithm for calculating a cylindrical linear DC motor with axially magnetized permanent magnets as part of a magnetic system with a radial direction of magnetization has been developed, which differs by taking into account the features due to the architecture of building the moving part of a cylindrical linear electric motor;

structures of finite element models have been developed, which are distinguished by a special set of boundary conditions in the edge zones;

recommendations have been developed for choosing rational design solutions aimed at improving the specific energy performance and dynamic qualities of cylindrical linear DC motors based on quantitative data from numerical calculations, as well as the results of experimental studies of prototypes.

The practical significance of the work. The practical value of the dissertation work is:

Algorithm for designing cylindrical linear motors
low power;

finite element models in the two-dimensional analysis of cylindrical linear motors, which allow comparing the specific characteristics of motors of various designs of magnetic systems;

The proposed models and algorithm can be used as a mathematical basis for creating special means applied software computer-aided design systems for non-contact DC motors.

Implementation of work results. The obtained theoretical and experimental results of the dissertation work were used at the enterprise "Research Institute of Mechanotronics - Alfa" when performing research work "Research on ways to create modern high-resource mechatronic actuating drives of various types of motion in variations with a digital information channel and sensorless control in the identification of phase coordinates integrated into space life support systems devices (SC)”, R&D “Research of ways to create “intelligent” linear motion electric drives with state vector control for spacecraft automation systems”, R&D “Research and development of intelligent mechatronic linear precision motion propulsion devices with non-traditional modular layout for industrial, medical and special equipment of a new generation”, as well as introduced into the educational process of the Department of Electromechanical Systems and Power Supply of the State Educational Institution of Higher Professional Education “Voronezh State Technical University” in lecture course"Special Electric Machines".

Approbation of work. The main provisions of the dissertation work were reported at the regional scientific and technical conference "New technologies in scientific research, design, management, production"

(Voronezh 2006, 2007), at the interuniversity student scientific and technical

conference "Applied Problems of Electromechanics, Energy, Electronics" (Voronezh, 2007), at the All-Russian Conference "New Technologies in Research, Design, Management, Production" (Voronezh, 2008), at the international school-conference " High tech Energy Saving” (Voronezh, 2008), at the I International Scientific and Practical Conference “Youth and Science: Reality and Future” (Nevinnomyssk, 2008), at the Scientific and Technical Council of the “Research and Design Institute of Mechanotronics-Alpha” (Voronezh, 2008), at scientific and technical conferences of the faculty and graduate students of the Department of Automation and Informatics in Technical Systems of the VSTU (Voronezh, 2006-2008). In addition, the results of the dissertation were published in the collections of scientific papers "Electrotechnical complexes and control systems", "Applied problems of electromechanics, energy, electronics" (Voronezh, 2005-2007), in the journal "Electrotechnical complexes and control systems" (Voronezh, Russia). Voronezh 2007-2008), in the Bulletin of the Voronezh State Technical University (2008).

Publications. 11 publications on the topic of the dissertation scientific works, including 1 - in publications recommended by the Higher Attestation Commission of the Russian Federation.

Structure and scope of work. The dissertation consists of an introduction, four chapters, a conclusion, a list of references of 121 titles, the material is presented on 145 pages and contains 53 figures, 6 tables and 3 appendices.

In the first chapter reviewed and analyzed state of the art in the field of development of linear electric motors of direct action. The classification of direct-acting linear electric motors is carried out according to the principle of operation, as well as according to the main designs. The issues of the theory of development and design of linear motors are considered, taking into account the features of a linear machine. The use of the finite element method as a modern tool for designing complex electrical

mechanical systems. The purpose of the work is set and research tasks are formulated.

In the second chapter the issues of the formation of a methodology for designing non-contact cylindrical linear DC motors are considered, an electromagnetic calculation of various design implementations of the magnetic systems of a linear motor is presented, containing next steps: selection of basic dimensions, power calculation; calculation of the machine constant; determination of thermal and electromagnetic loads; calculation of winding data; calculation of electromagnetic traction force; calculation of the magnetic system, selection of sizes of permanent magnets. An estimated calculation of the heat transfer process of a linear electric motor has been made.

In the third chapter the expressions of the universal optimization criterion are given, which allows to perform comparative analysis DC and AC motors of low power, taking into account the requirements for energy and speed. The provisions of the methodology for modeling a cylindrical linear DC motor by the finite element method are formed, the main assumptions are determined, on which the mathematical apparatus for analyzing models of these types of motors is built. Two-dimensional finite element models for a cylindrical linear motor for various designs of the moving part are obtained: with pseudo-radial magnetization of segment magnets on the rod and with axially magnetized magnets-washers.

In the fourth chapter a practical development of samples of cylindrical linear synchronous motors is presented, a circuit implementation of a control unit for a cylindrical linear motor is shown. The principles of controlling the specified electric motor are highlighted. The results of experimental studies of a cylindrical linear synchronous motor with a different design of the magnetic system of the moving part, including: studies of the thermal modes of the electric motor,

dependence of the traction force of the electric motor on currents and displacement. A comparison of the results of modeling by the finite element method with a physical experiment was carried out, an assessment of the obtained parameters of a linear motor with the modern technical level was carried out.

In conclusion, the main results of the theoretical and experimental studies carried out are presented.

Analysis of the developed design of a cylindrical linear electric motor

A linear electric drive with state vector control imposes a number of specific requirements on the design and operation of the CLSD. The energy flow from the network through the control device enters the armature winding, which ensures the correct sequence of interaction between the electromagnetic field of the winding and the field of permanent magnets of the moving rod in accordance with adequate switching laws. If a high-coercivity permanent magnet is located on the rod, then the armature reaction practically does not distort the main magnetic flux. The quality of electromechanical energy conversion is determined not only by a rationally chosen magnetic system, but also by the ratio of the energy parameters of the magnet brand and the linear load of the stator armature winding. The calculation of the electromagnetic field of the FEM and the search for a rational design of the electric machine by the method of numerical experiment, directed with the help of the obtained optimization criterion, makes it possible to do this with minimal costs.

Taking into account modern requirements for resource, range of regulation and positioning, the layout of the CLSD is built according to the classical principle of dynamic interaction of the magnetic flux of excitation of the moving rod with the magnetic flux of the armature winding of the slotless stator.

A preliminary technical analysis of the developed design made it possible to establish the following:

The issue of motor energy depends on the number of phases and the armature winding switching circuit, while the shape of the resulting magnetic field in the air gap and the shape of the voltage supplied to the winding phases play an important role;

On the moving rod are rare-earth permanent magnets with a pseudo-radial magnetization structure, each of which consists of six segments, combined into a hollow cylindrical structure;

In the developed design, it is possible to ensure the technological unity of the working mechanism and the CLSD rod;

Bearing supports with optimized load factors provide the necessary quality margin in terms of the level of guaranteed operating time and the range of regulation of the rod travel speed;

The possibility of precision assembly with minimal tolerances and ensuring the necessary selectivity of the mating surfaces of parts and assemblies allows you to increase the service life;

The ability to combine translational and rotational types of motion in a single engine geometry allows you to expand its functionality and expand the scope.

The TsLSD anchor is a cylinder made of soft magnetic steel, that is, it has a slotless design. The magnetic circuit of the armature yoke is made of six modules - bushings, overlapped and made of steel 10 GOST 1050-74. The bushings have holes for the output ends of the coils of the two-phase armature winding. The bushings, assembled in a package, essentially form a yoke for conducting the main magnetic flux and obtaining the required value of magnetic induction in the total non-magnetic working gap. The slotless design of the armature is the most promising in terms of ensuring high speed uniformity in the region of the minimum values ​​of the linear speed control range, as well as the positioning accuracy of the moving rod (there are no pulsations of the electromagnetic traction force of the tooth order in the non-magnetic gap). The armature winding coils are drum-shaped, the turns of the winding are made of wire with self-sintered insulation PFTLD or with enamel insulation PETV GOST 7262-54, impregnated with a thermosetting compound based on epoxy resin, wound on an aluminum frame with a rigid shape and designed for temperatures up to 200 C. After molding and polymerization of the impregnating compound, the coil is a rigid monolithic unit. Bearing shields are assembled together with anchor yoke modules. Bearing shield housings are made of aluminum alloy. Bronze bushings are installed in the bearing shield housings.

According to the results of the patent search, two constructive implementations of magnetic systems were identified, which differ mainly in the magnetic system of the moving part of the cylindrical linear motor.

The movable rod of the basic design of the electric motor contains rare-earth permanent magnets N35, between which non-ferromagnetic separating washers are installed, has 9 poles (of which no more than 4 are covered in the active length of the machine). The design of the machine provides balancing of the magnetic field from permanent magnets in order to reduce the primary longitudinal edge effect. High coercivity magnets provide the required level of induction in the air gap. The permanent magnets are protected by a non-ferromagnetic sleeve, which provides the functions of a guide and has the desired properties of the sliding surface. The material of the guide sleeve must be non-ferromagnetic, that is, the sleeve must not shield the magnetic field of the winding and magnet modules, the flux linkage of which must be maximum. At the same time, the sleeve must have the specified mechanical properties, guaranteeing a high service life and a low level of mechanical friction losses in linear bearings. It is proposed to use corrosion-resistant and heat-resistant steel as the sleeve material.

It should be noted that the increase in specific energy performance is usually achieved through the use of permanent magnets with high magnetic energy, in particular from alloys with rare earth metals. At present, the overwhelming majority of the best products use neodymium - iron - boron (Nd-Fe-B) magnets with additives from materials such as dysprosium, cobalt, niobium, vanadium, gallium; etc. The addition of these materials leads to an improvement in the stability of the magnet from a temperature point of view. These modified magnets can be used up to +240C.

Since the bushings of permanent magnets must be magnetized radially, a technological problem arose during their manufacture due to the need to provide the required flux for magnetization and small geometric dimensions. A number of developers of permanent magnets noted that their enterprises do not produce radially magnetized permanent magnets from rare earth materials. As a result, it was decided to develop a permanent magnet sleeve in the form of a magnet - an assembly of six curvilinear prisms - segments.

By developing and then comparing the energy performance of magnetic systems, we will evaluate the energy capabilities, and also consider the compliance of the performance of the electric motor with the current technical level.

The diagram of a cylindrical linear synchronous motor with a longitudinally radial magnetic system is shown in Figure 1.8.

As a result of comparison and analysis of the level of energy indicators of two, developed in the course of research, constructive implementations of magnetic systems obtained as a result of a physical experiment, the adequacy of analytical, numerical methods for calculating and designing the type of linear electric motor under consideration will be confirmed in subsequent sections.

Algorithm for Electromagnetic Calculation of a Cylindrical Linear DC Motor

The following data are the basis for calculating the CLSD:

Dimensions;

Stroke length of the moving part (rod)

Synchronous rod speed Vs, m/s;

Critical (maximum) value of electromagnetic tractive force FT N;

Supply voltage /, V;

Engine operation mode (continuous, PV);

Temperature range environment AT,S;

Engine version (protected, closed).

In inductive electric machines, the energy of the electromagnetic field is concentrated in the working gap and the tooth zone (there is no tooth zone in the CLDPT with a smooth armature), so the choice of the volume of the working gap in the synthesis of an electric machine is of paramount importance.

The specific energy density in the working gap can be defined as the ratio of the active power of the machine Рg to the volume of the working gap. The classical methods for calculating electrical machines are based on the choice of the machine constant SA (Arnold's constant), which connects the main design dimensions with permissible electromagnetic loads (they correspond to the maximum thermal load)

To ensure the sliding of the rod, a sleeve with a thickness of Ar is put on permanent magnets. The value of Ag depends on technological factors and is chosen as the minimum possible.

The linear synchronous speed of the CLDPT rod and the equivalent synchronous speed are related by the relation

To ensure the required value of the traction force with a minimum value of the time constant and the absence of a fixing force (reducing it to an acceptable value), preference was given to a toothless design with excitation from permanent magnets based on high-energy hard magnetic materials (neodymium - iron - boron). In this case, the motor has a working gap sufficient to accommodate the winding.

The main task of calculating the magnetic system is to determine the design parameters that are optimal in terms of energy parameters, traction force and other indicators that provide a given value of the magnetic flux in the working gap. At the initial design stage, the most important thing is to find a rational relationship between the thicknesses of the back of the magnet and the coil.

The calculation of a magnetic system with permanent magnets is associated with the determination of the demagnetization curve and the magnetic conductivities of individual sections. Permanent magnets are inhomogeneous, the field pattern in the gap is complex due to the longitudinal edge effect and scattering fluxes. The surface of the magnet is not equipotential, individual sections, depending on the position relative to the neutral zone, have unequal magnetic potentials. This circumstance makes it difficult to calculate the leakage magnetic conductivities and the leakage flux of the magnet.

In order to simplify the calculation, we accept the assumption of the uniqueness of the demagnetization curve, and replace the actual leakage flux, which depends on the distribution of the MMF along the magnet height, with the calculated one, which passes along the entire height of the magnet and completely leaves the pole surface.

There are a number of graphic-analytical methods for calculating magnetic circuits with permanent magnets, of which the demagnetizing factor method used to calculate direct magnets without reinforcement has found the greatest application in engineering practice; the ratio method used to calculate magnets with armature, as well as the electrical analogy method used to calculate branched magnetic circuits with permanent magnets.

The accuracy of further calculations largely depends on the errors associated with determining the state of magnets with a useful specific energy with z.opt developed by them in a non-magnetic working gap 8v. The latter must correspond to the maximum product of the induction of the resulting field in the working gap and the specific energy of the magnet.

The distribution of induction in the working gap of the CLSD can be most accurately determined in the course of finite element analysis of a specific calculation model. At the initial stage of the calculation, when it comes to choosing a certain set of geometric dimensions, winding data and physical properties of materials, it is advisable to set the average effective value of the induction in the working gap Bscp. The adequacy of the B3av task within the recommended interval will actually determine the complexity of the verification electromagnetic calculation of the machine by the finite element method.

The used hard magnetic rare-earth magnets based on rare-earth metals have an almost relay demagnetization curve, therefore, in a wide range of changes in the magnetic field strength, the value of the corresponding induction changes relatively little.

To solve the problem of determining the height of the magnet-segment back hM at the first stage of the CLSD synthesis, the following approach is proposed.

Description of input data for modeling

At the heart of electromagnetic calculation numerical method lies a model that includes the geometry of the machine, the magnetic and electrical properties of its active materials, regime parameters and operating loads. During the calculation, inductions and currents in the sections of the model are determined. Then forces and moments are determined, as well as energy indicators.

Building a model includes the definition of a system of basic assumptions that establishes the idealization of the properties of the physical and geometric characteristics of the structure and loads, on the basis of which the model is built. The design of the machine, made of real materials, has a number of features, including shape imperfection, dispersion and inhomogeneity of material properties (deviation of their magnetic and electrical properties from the established values), etc.

A typical example of the idealization of a real material is the assignment of homogeneity properties to it. In a number of designs of linear motors, such idealization is impossible, because it leads to incorrect calculation results. An example is a cylindrical linear synchronous motor with a non-ferromagnetic conductive layer (sleeve), in which the electrical and magnetic properties change abruptly when crossing the interface between materials.

In addition to saturation, the output characteristics of the engine are greatly influenced by the surface and longitudinal edge effects. In this case, one of the main tasks is to set the initial conditions at the boundaries of the active regions of the machine.

Thus, the model can be endowed with only a part of the properties of a real structure, so its mathematical description is simplified. The complexity of the calculation and the accuracy of its results depend on how well the model is chosen.

The mathematical apparatus for the analysis of models of cylindrical linear synchronous motors is based on the equations of the electromagnetic field and is built on the following basic assumptions:

1. The electromagnetic field is quasi-stationary, since the displacement currents and the delay in the propagation of an electromagnetic wave within the field region are negligible.

2. Compared with conduction currents in conductors, conduction currents in dielectrics and convection currents that arise when charges move along with the medium are negligible, and therefore the latter can be neglected. Since conduction currents, displacement currents and convection currents in the dielectric filling the gap between the stator and the rotor are not taken into account, the speed of movement of the dielectric (gas or liquid) in the gap does not. influence on the electromagnetic field.

3. The magnitude of the EMF of electromagnetic induction is much greater than the EMF of Hall, Thompson, contact, etc., and therefore the latter can be neglected.

4. When considering the field in a non-ferromagnetic medium, the relative magnetic permeability of this medium is assumed to be unity.

The next stage of the calculation is the mathematical description of the behavior of the model, or the construction of a mathematical model.

The electromagnetic calculation of the FEM consisted of the following steps:

1. Selecting the type of analysis and creating the geometry of the model for the FEA.

2. Selecting element types, entering material properties, assigning material and element properties to geometric regions.

3. Partitioning of model areas into finite element mesh.

4. Application to the model of boundary conditions and loads.

5. Selecting the type of electromagnetic analysis, setting the solver options and numerical solution of the system of equations.

6. Using postprocessor macros for calculating the integral values ​​of interest and analyzing the results.

Stages 1-4 refer to the pre-processor stage of the calculation, stage 5 - to the processor stage, stage 6 - to the post-processor stage.

The creation of a finite element model is a laborious step in the calculation of the FEM, because associated with the reproduction of the most accurate possible geometry of the object and the description of the physical properties of its regions. Justified application of loads and boundary conditions also presents certain difficulties.

The numerical solution of the system of equations is performed automatically and, all other things being equal, is determined by the hardware resources of the computer technology used. The analysis of the results is somewhat facilitated by the visualization tools available as part of the software used (PS), however, this is one of the least formalized stages, which has the greatest labor intensity.

The following parameters were determined: the complex vector potential of the magnetic field A, the scalar potential Ф, the magnitude of the magnetic field induction B and the strength H. An analysis of the time-varying fields was used to find the effect of eddy currents in the system.

Solution (7) for the case of alternating current has the form of a complex potential (characterized by amplitude and phase angle) for each node of the model. The magnetic permeability and electrical conductivity of the area material can be specified as a constant or as a function of temperature. The PSs used make it possible to apply the appropriate macros at the postprocessor stage to calculate the series the most important parameters: energy of the electromagnetic field, electromagnetic forces, eddy current density, electrical energy losses, etc.

It should be emphasized that in the course of finite element modeling, the main task is to determine the structure of models: the choice of finite elements with specific basic functions and degrees of freedom, the description of the physical properties of materials in various areas, the assignment of applied loads, as well as initial conditions at the boundaries.

As follows from the basic concept of the FEM, all parts of the model are divided into sets of finite elements connected to each other at vertices (nodes). Finite elements of a rather simple form are used, in which the field parameters are determined using piecewise polynomial approximating functions.

The boundaries of finite elements in two-dimensional analysis can be piecewise linear (elements of the first order) or parabolic (elements of the second order). Piecewise linear elements have straight sides and nodes only at the corners. Parabolic elements may have an intermediate node along each of the sides. It is thanks to this that the sides of the element can be curvilinear (parabolic). With an equal number of elements, parabolic elements give greater accuracy of calculations, since they more accurately reproduce the curvilinear geometry of the model and have more accurate shape functions (approximating functions). However, the calculation using finite elements of high orders requires large hardware resources and more computer time.

There are a large number of used types of finite elements, among which there are elements that compete with each other, while for various models there is no mathematically justified decision on how to split the area more efficiently.

Since a computer is used to build and solve the considered discrete models due to the large amount of information being processed, the condition of convenience and simplicity of calculations is important, which determines the choice of admissible piecewise polynomial functions. In this case, the question of the accuracy with which they can approximate the desired solution becomes of paramount importance.

In the problems under consideration, the unknowns are the values ​​of the vector magnetic potential A in the nodes (vertices) of the finite elements of the corresponding areas of a specific machine design, while the theoretical and numerical solutions coincide in the central part of the finite element, so the maximum accuracy of calculating magnetic potentials and current densities will be in the center of the element.

The structure of the control unit of a cylindrical linear motor

The control unit implements software control algorithms for a linear electric drive. Functionally, the control unit is divided into two parts: information and power. The information part contains a microcontroller with input/output circuits for discrete and analog signals, as well as a data exchange circuit with a computer. The power section contains a circuit for converting PWM signals into phase winding voltages.

The electrical circuit diagram of the linear motor control unit is presented in Appendix B.

The following elements are used to power the information part of the control unit:

Formation of power supply with a stabilized voltage of +15 V (power supply for microcircuits DD5, DD6): filter capacitors СІ, С2, stabilizer + 15 V, protective diode VD1;

Formation of power supply with a stabilized voltage of +5 V (power supply for microcircuits DD1, DD2, DD3, DD4): resistor R1 to reduce the thermal loads of the stabilizer, filter capacitors C3, C5, C6, adjustable voltage divider on resistors R2, R3, smoothing capacitor C4, adjustable stabilizer +5 V.

Connector XP1 is used to connect the position sensor. The microcontroller is programmed through the XP2 connector. Resistor R29 and transistor VT9 automatically generate a logical "1" signal in the reset circuit in control mode and does not participate in the operation of the control unit in programming mode.

HRZ connector, DD1 chip, capacitors C39, C40, C41, C42 transfer data between the personal computer and the control unit in both directions.

To form a voltage feedback for each bridge circuit, the following elements are used: voltage dividers R19-R20, R45-R46, amplifier DD3, filtering RC circuits R27, R28, C23, C24.

The logic circuits implemented using the DD4 chip make it possible to implement bipolar symmetrical switching of one motor phase using one PWM signal supplied directly from the microcontroller pin.

To implement the necessary control laws for a two-phase linear electric motor, separate generation of currents in each stator winding (fixed part) using two bridge circuits is used, providing an output current of up to 20 A in each phase at a supply voltage of 20 V to 45 V. Power switches are used MOSFETs VT1-VT8 IRF540N from International Rectifier (USA), having a fairly low drain-source resistance RCH = 44 mOhm, an acceptable price and the presence of a domestic analogue 2P769 from VZPP (Russia), manufactured with acceptance of OTK and VP.

Specific requirements for the MOSFET control signal parameters: a relatively large gate-source voltage is required for full inclusion MOSFET, to ensure fast switching, it is necessary to change the gate voltage for a very short time (fractions of microseconds), significant recharge currents of the input capacitances of the MOSFET, the possibility of their damage when the control voltage is reduced in the “on” mode, as a rule, dictate the need use of additional conditioning elements for input control signals.

To quickly recharge the input capacitances of MOSFETs, the pulsed control current should be approximately 1A for small devices and up to 7A for high power transistors. Coordination of low-current outputs of general-purpose microcircuits (controllers, TTL or CMOS logic, etc.) with a high-capacity gate is carried out using special pulse amplifiers (drivers).

The review of the drivers made it possible to identify two drivers Si9978DW from Vishay Siliconix (USA) and IR2130 from International Rectifier (USA) that are most suitable for controlling a MOS transistor bridge.

These drivers have built-in undervoltage protection for transistors, while ensuring the required supply voltage at the gates of the MOSFETs, are compatible with 5V CMOS and TTL logic, provide very fast switching speeds, low power scattering and can operate in the bootstrap mode (at frequencies from tens of Hz to hundreds of kHz), i.e. do not require additional weighted power supplies, which allows you to get a circuit with a minimum number of elements.

In addition, these drivers have a built-in comparator to implement an overcurrent protection circuit and a built-in through-current suppression circuit in external MOSFETs.

IR2130 microcircuits from International Rectifier DD5, DD6 were used as drivers for the control unit, since, other things being equal, the technical conditions are more widespread on the Russian market of electronic components and there is the possibility of their retail purchase.

The bridge circuit current sensor is implemented using resistors R11, R12, R37, R38, selected to implement current limiting at the level of 10 A.

With the help of a current amplifier built into the driver, resistors R7, R8, SW, R34, filtering RC circuits R6, C18-C20, R30, C25-C27, Feedback on the phase currents of the electric motor. The layout of the prototype panel of the direct-acting linear electric drive control unit is shown in Figure 4.8.

To implement control algorithms and fast processing of incoming information, the digital microcontroller AVR ATmega 32 of the Mega family manufactured by At-mel was used as a DD2 microcontroller. Mega family microcontrollers are 8-bit microcontrollers. They are manufactured using low-power CMOS technology, which, in combination with an advanced RISC architecture, achieves the best performance/power ratio.