SU1458962A1 - Method and apparatus for controlling induction electric drive - Google Patents

Abstract

1. A method of controlling an asynchronous electric drive in which instantaneous symmetric phases are formed. voltages on the stator windings of an asynchronous motor with amplitude, frequency and phase, depending on the measured rotational speed and two input effects, one of which is constant and corresponds to the required amplitude of the rotor flux linkage, and the other corresponds to In order to increase the quality of regulation by increasing the speed when monitoring the instantaneous phase phase voltages on the stator windings, they form instantaneous symmetric phase voltages on the stator windings and according to) k, ((about 4.KjM) "-OS j (y + K, M) dt1 - + ь l XCOS. Gg / 1 dtj J) dt, + K, where Ug (t) is instantaneous phase voltage; Фр - constant control action corresponding to the required amplitude of the rotor flux linkage, M - control action corresponding to the required moment; CO is the measured rotational speed of an asynchronous motor -, KB constant coefficients determined by the parameters of the induction motor i t - time. 2. A device for controlling an asynchronous electric drive containing an asynchronous motor with a short-circuited rotor, the stator windings of which are connected to the outputs of an autonomous voltage inverter connected by control inputs to the outputs of the coordinate conversion unit made to the control input in frequency with both the first and the second control inputs on the quadrature components of the stator voltage, serially connected speed controller, first comparison element, proportional-integral regulator speeds and the first adder, a speed sensor mounted on the shaft of an asynchronous motor with a short-circuited rotor, connected by an output to the other inputs of the first comparison element and the first adder combined, the multiplication unit. (L 4, SL 00 with with to

Description

14

the first input of which is connected to the output of the proportional-integral speed controller, and the output is connected to one of the inputs of the second comparison element connected by another input to the output of the initial rotor-flow control unit; the second adder, the first input of which is combined with the second input of the multiplication unit, the control input of the frequency unit of the coordinate transformation and connected to the output of the first adder, the second input of the second adder through the scale element is connected to the output of the proportional-integral speed controller spins, and the outputs of the second reference element and the output of the second adder are connected respectively to the first and second control inputs and inputs on the quadrature components of the stator voltage of the coordinate conversion unit, which is different in that in order to increase the quality of transient processes by increasing -speed, a differentiation element is introduced, and the second adder is provided with an additional third input connected to the output of the differentiation element, the input of which is connected to the output of the proportional-integral regulator speed torus of

3. The device according to claim 2, characterized in that the coordinate conversion unit is equipped with a voltage-frequency converter, an address counter, first and second permanent memory blocks programmed according to the sine and cosine laws, a block of adders and four digital-analogue converters, respectively. , digital inputs of the first and second of them are connected to the output of the first permanent storage unit, analog inputs of the first and third, second and fourth digital-to-analog converters are pairwise combined The first and second control inputs, respectively, over the quadrature components of the stator voltage of the coordinate conversion unit, form the input of the voltage converter — the frequency forms the control input over the frequency of the coordinate conversion unit, and the output is connected to the input of the address counter connected to the output inputs of permanent storage blocks, outputs of digital-to-analog converters are connected to the inputs of the block of adders, the codes of which form the outputs of the block of coordinate transformation.

one

The invention relates to electrical engineering, in particular, to an adjustable electric drive built on an asynchronous motor with a short-circuited rotor, and can be used to control the speed and torque of the working parts of machines and mechanisms, for example, in drives of machine tools, welding units, industrial robots and tracking systems of various purposes.

The aim of the invention is to improve the quality of regulation by increasing the speed in monitoring the instantaneous phase phase voltages on the stator windings.

FIG. 1 shows a functional diagram of an apparatus for controlling an asynchronous electric drive implementing this method; in fig. 2 is a functional diagram of a coordinate conversion unit; in fig. 3 and 4-- diagrams explaining the operation of the device.

A device for controlling an asynchronous electric drive (Fig. 1) contains an asynchronous motor 1 with a short-circuited rotor, the stator windings of which are connected to the outputs of an autonomous voltage inverter 2 connected by control inputs of the coordinate conversion unit 3, which is connected to the control input in frequency and with the first and second control inputs on the quadrature components of the stator voltage, serially connected setpoint 4 speeds, the first comparison element 5, proportional-integral control speed 6 torus and first adder 7, speed sensor 8 mounted on the shaft of an asynchronous motor 1 with a short-circuited rotor, connected upstream to another input of the first comparison element 5 and first adder 7, unit 9 multiplying, first input which is connected to the output of the proportional-integral speed controller 6, and the output to one of the inputs of the second comparison element 10 connected by another input to the OUTPUT of the setpoint generator 11 of the initial rotor flux linkage, the second adder 12, the first input of which dinene with the second input of the multiplication unit 9, with the control input for the frequency of the coordinate converting unit 3 and connected to the output of the first adder 7, the second input of the second adder 12 through the scale element 13 is connected to the output of the proportional-integral speed controller 6, and the output of the second element 10 and the output of the second adder 12 are connected respectively to the first and second control inputs by the quadrature components of the stator voltage of the coordinate conversion unit 3. Into a device for controlling an asynchronous electric drive

digital-to-analog converters 22 and 23 to the output of the second permanent storage unit, 18,

The analog inputs of the digital-to-analog converters 20, 22 and 21, 23 are pairwise interconnected and form the first and second control inputs, respectively, over the quadrature 1Q components of the stator voltage of the coordinate conversion unit 3. The input of the voltage converter 15 is the frequency that forms the control input for the frequency of the ordinate conversion unit 3, and the output is connected to the input of the address counter 16 connected by the output to the permanent memory inputs. and 17 and 18. The outputs of digital-to-analog converters 20-23 under 20 are connected to the inputs of the block 19 adders whose outputs form the outputs of the coordinate conversion unit 3.

The device for controlling an asynchronous electric drive works as follows.

At the output of the speed limiter 4, the voltage setting voltage speed CO is formed. PROSO O and the absence of a signal at the output of the speed sensor 8, the stalled at the output of the comparison element 10 is equal to the set point y defined by the initial rotor flux linking unit 11. With the help of unit 3, the coordinate conversion is indicated by the charter

. the voltage is converted into three constant voltages, worked out by an independent inverter 2 voltage with pulse-width modulation. In this case, the stator windings asynchronous

- - - -m-- -.v.-i i iaiupnbit; asynchronous closures

differentiation element 14. The second one about the Engine 1 is supplied with a constant. The iz is supplied with a pop.

y C rotor flux adhesion,

adder 12 is provided with an additional

the third entrance connected to you is constant in magnitude and motionless

in the course of element 14 of differentiation, in space. Moment and speed

whose entrance is connected to. rotation of the asynchronous motor of the rapprochement-integral controller. us zero.

6 GKPPPG-TbT J-, o

The coordinate transformation block J in the specified mode does not change the phase of the output voltage, since the output voltage of the converter 15 is gjj frequency (Fig. 2), there are no sweep pulses, the address counter 16 determines an arbitrary state of the permanent storage blocks 17 and 18

6 speeds.

The coordinate conversion unit 3 is equipped (Fig. 2) with a voltage-frequency converter 15, an address counter 16, first and second permanent memory blocks 17 and 18, programmed according to the sine and cosine laws, block 19. adders and a digital-analog converter 20-23. Digital inputs of digital-to-analog converters 20 and 21 are connected to the output of the first permanent storage unit 17, and digital inputs result in digital-to-gg analog converters 20 and 22 with arbitrary discrete samples of the sinus and cosine functions, two constant voltages are formed, defined by the setting (,

589624

digital-to-analog converters 22 and 23 to the output of the second permanent storage unit, 18,

The analog inputs of the digital-to-analog converters 20, 22 and 21, 23 are pairwise interconnected and form the first and second control inputs, respectively, over the quadrature 1Q components of the stator voltage of the coordinate conversion unit 3. The input of the voltage converter 15 is the frequency that forms the control input for the frequency of the ordinate conversion unit 3, and the output is connected to the input of the address counter 16 connected by the output to the permanent memory inputs. The connecting blocks 17 and 18. The outputs of the digital-analog converters 20-23 are connected to the inputs of the block 19 of adders, the outputs of which form the outputs of the block 3 of the coordinate conversion.

The device for controlling an asynchronous electric drive works as follows.

At the output of the speed limiter 4, the voltage setting voltage speed CO is formed. PROSO O and the absence of a signal at the output of the speed sensor 8, the stalled at the output of the comparison element 10 is equal to the set point y defined by the initial rotor flux linking unit 11. With the help of unit 3, the coordinate conversion is indicated by the charter. the voltage is converted into three constant voltages, worked out by an independent inverter 2 voltage with pulse-width modulation. In this case, the stator windings asynchronous

-.v.-i i iaiupnbit; asynchronous closures

Engine 1 is powered constant by

Engine 1 is fed constant by

y C rotor flux adhesion,

constant in magnitude and still

The coordinate transformation block J in the indicated mode does not change the phase of the output voltage, since the output voltage of the converter 15 is gjj frequency (Fig. 2), there are no sweep pulses, the address counter 16 determines an arbitrary state of the permanent storage units 17 and 18

resulting in the outputs of digital-gg analog converters 20 and 22 with arbitrary discrete samples of the sine and cosine functions, two constant voltages are formed, defined by the setting (,

5145896

The vector diagram (Fig. 3) is the initial state of the asynchronous motor 1, in which the stator outflow vector Ug, the current vector tator i and the vector threading vector (are constant. Moreover, all these vectors coincide in the direction Vector the stator flux linkage coincides with the direction of the ю vector (and the moment is zero.

When the voltage setting element 5 is applied to the reference, the voltage jump with its subsequent increase, the rate of which determines the voltage value at the output of the differentiation element 14, occurs at the output of the proportional-integral controller 6 of speed 15. As a result, the voltage 20 and at the output of the comparison element 10 decreases with a disk and then decreases continuously, the voltage U at the output of the second adder 12 increases and then continuously increases, and the voltage from the output of the first adder 7 also changes abruptly and is increasing.

At the output of the coordinate conversion unit 3, there is a jump and changes of some phases of three-phase voltage, a jump and change of its amplitude and frequency. These changes in the control voltages at the input of the autonomous inverter 2 voltage with pulse-width modulation lead to similar changes in the phase, frequency and amplitude of the three-phase stator voltage of the asynchronous motor 1.

Due to the inertia of the spatial movement of the rotor flux linkage vector with a forced increase in the voltage U and a decrease in Ug, a phase jump of the stator current vector i and jump 45 of the stator flux linkage is formed (Fig. 4). An engine torque is generated, the rotor speed increases, the output voltage of speed sensor 8 increases, which reduces the output voltage of proportional-integral speed controller 6, corresponding to the required torque M, until the required torque M and load torque 55 M are equal. on the shaft of the induction motor 1,

The increment of the required moment M and the actual moment M occurs before leveling off the required speed35

five

ABOUT

0 5 5

26

ti (jO and actual speed bz. As a result, the specified electric drive has absolutely rigid mechanical characteristics of the speed at any, including intermittent, change in the moment M.

The stator voltage phase, set with a small discretization step of order 1, is controlled by the interconnected variation of three input analog voltages of the coordinate conversion unit 3, one of which characterizes the required stator voltage oz iff when the other two input voltages are constant Life U const,

and const in static mode

motor drive, and in the general case corresponds to the required frequency of the rotor flux linkage ((t) and the angular velocity of rotation of the rotor flux linkage vector relative to the stator

Ca 2Tfrj. Second input analog 9 t t

the new voltage characterizes the first quadrature component of the stator voltage U. The third input analog voltage And characterizes the second quadrature component of the stator voltage Ug. The amplitude of the stator voltage Ug and its two quadrature components are related by

(one)

and 4 and | + id

oh lx

five

where Uc and Ue. - projection of the vector of rt

prints in cartesian

coordinate system oriented along the rotor flux link vector fg.

The value of Ug is changed depending on the required moment M and the required frequency of COg, defined as

the difference between setting V and voltage

portioned product) 5, formed at the output of block 9 multiplication. The setpoint φ determines the magnitude of the initial flux linkage of the rotor. C) C. At the same time, the interrelated actions over the COg frequency and quadrature components and U, 5 "are determined from the condition of constant amplitude of the rotor flux linkage in all operating modes of the asynchronous motor C) p I f I Vv-const of the known differential equations describing electromagnetic transient processes in asynchronous motor.

 14589628

in the constant flow mode, 20, 21 and 22, 23 corresponding to the rotor t) is the difference of the absolute angular velocities of rotation relative to the stator axis S of the rotor vector sense of the rotor (|; p. of the rotor vector Cz, (FIG. 4), corresponding to the rotor flux-coupling vector f. relative to the rotor is proportional to the torque of the engine:

as a result, each sample is discrete cos q) g and sincp

multiplied by the second and third anai and;

ten

the log voltages U, and U, are fed to the corresponding analog inputs of the indicated digital-to-analog converters. At the outputs of digital-to-analog converters 20-23, discretely varying analog voltages are formed, proportional to the products of the quadrature components of the voltages U and ID and cosine and

D "g SE - O),

2

R

where zp is the number of pole pairs; Rf, is the resistance of the rotor; (PO is the amplitude of flux linking

rotor

M - the moment of the engine. Since the purpose of controlling the moment is to match the actual moment of M to the required moment M, i.e.

M M

(3) 25

Then, the controlled frequency of the stator voltage, proportional to the required torque M, characterizes, according to (2), the required angular velocity of the rotor flux vector in relation to the rotor dso, and the sum of this frequency and rotor speed determines the required absolute angular velocity of the rotor flux linkage vector with respect to the fixed stator axis i.e. the required frequency of the rotor flux linkage, which | RUU is set by the output voltage of the first adder 5 and is converted into a sequence of sweep pulses by means of the voltage-frequency converter 15. Each output sweep of the voltage converter 15 is frequency shifted the phase angle tfg of the rotor flux linkage with respect to the stator axis § (Fig. 4) by one discrete component of a small value (on the order of l) using the address counter 16 and fixed memory blocks 17 and 18, at the output of which codes of discrete samples of the sinus and cosine functions of the phase angle of the rotor flux linkage qjg are formed, namely cos at the output of block 17, sinqig - at the output of block 18.

"

The cos Cfs and Sin codes go to the digital inputs of the digital to analog preo

as a result, each sample is discrete cos q) g and sincp

multiplied by the second and third anai and;

ten

the log voltages U, and U, are fed to the corresponding analog inputs of the indicated digital-to-analog converters. At the outputs of digital-to-analog converters 20-23, discretely varying analog voltages are formed, proportional to the product of the quadrature components of the voltages U and ID to cosine and

15 is the sine of the phase angle of the rotor flux linkage, which are summed up in block 19 adders according to known

. vector transformation equations from Cartesian rotating system - 20 m1 y, X, to Cartesian stationary

the system coordinator, In, oriented along the axis of the stator 5, namely by. phase winding axis a:

25

and,

 5Q s sy ostps- Us, sinc | j (4) 5 Usy-sinCfs Ug.cosCf (5)

where Ug is the instantaneous phase voltage of the stator in the stator reference phase winding q relative to which coordinate transformations are performed. 35 With the help of block 19 of adders, a two-phase voltage Ug, U forms a three-phase voltage corresponding to the stator supply voltage - windings taking into account the connection scheme 0 of the motor windings.

The control input of the frequency of the unit 3 of the coordinate conversion receives a signal corresponding to the frequency of change in the flux linkage of the roto 5 Pa. In this case, the voltages Ug, U are defined as the protections of the stator voltage vector Ug in the rotation

The coordinate system y, x oriented along the flux coupling vector rojj of the torus f, when the y axis coincides with the direction of the rotor flux coupling vector (ji, TeVrvj 9, Vr, 0.) Therefore, the voltage phase control Us (t is relative to the rotor flux coupling c, (t) is carried out by a process of interrelated actions on the quadrature components Ug Sx by the corresponding projections of the voltage vector Ug on the axis of the vector

rotor flux linkage (j and x axis, orthogonal to the rotor flux link vector ((FIG. 4).

These actions are determined depending on the required moment M and the required frequency of CO, taking into account the constant-amplitude mode of the constant flow amplitude of the rotor Ц from the known differential equations of an induction motor for a stator circuit during rotation of the coordinates y, x at a speed " five .

When the amplitude of the flux linkage of the rotor PO const, the amplitude of the flux linkage of the stator (e) is not constant, and the flux linkage phase of the stator relative to the flux linkage of the rotor varies depending on the motor torque so that the projection of the stator flux linkage vector to the y-axis, coinciding with the direction of the rotor flux linkage, post nna, t. e,:

 Ls.

 s

C g

(6)

V

5k

2 I Lh M

L.

and the phases of the stator voltage relative to the rotor flux linkage Vy, t,

(7) 30 ys cpg + j ((t) dt + usr,

where Lg, L Ll

stator inductance is mutual inductance; rotor inductance;

jg transient inductance. For the required moment M, proportional to the output voltage of the proportional-integral speed controller 6, subject to VIA (2) for the controlled frequency & CxfliQ and conditions for the total frequency at the output of the first adder 5

Yu:

BO + CO

(eight)

Taking into account the connections of the flux linkages (6), (7) and the quadrature components of the voltage (1) from the differential equations of the stator circuit, describing the relationship of the voltage projections and the projection of the stator flux linkage, the components of the stator voltage are:

tm -s. 2Ls Lr ,,. M.

.-h1; 1-,

(9)

2LeL dM

2RsL t - ,. -h ---..- M

3ZpL

Wrc

.j-b -, (, o,

At the same time, the control voltages and and inputs of the coordinate conversion unit 3 are defined as

and

. and, and post-94 -sij -M,

this control effect (| g 1 / K

as with

R5 / L (, (K and - coefficient U gp 1 1-0

transmission voltage in blocks 2 and 3).

The stator voltage phase jfg, equal to 5 at the phase angle of the voltage vector Us relative to the fixed axis of the stator, S, varies according to the proposed control method as the sum of the rotor flux linkage phase (jf,

0 equal to the phase angle of the rotor flux vector. (J relative to the fixed axis of the stator S, which is obtained by sweeping in time

oo

25 required frequency Cf,

J Qg (t) dt,

and the phases of the stator voltage relative to the rotor flux linkage Vy, (Fig.4): t,

(eleven)

 ys cpg + j ((t) dt + usr,

in this phase, the voltage of the stator relative to the flux linkage of the Yc rotor is changed by changing the ratio -g of the first and second quadrature voltage components;

Ouch arctgUs ,,.

(12)

According to the phase connection (11), the phase on

change by

yarn stator jf.

the change in the required frequency CO g and the relative phase voltage of the stator X Y defined by the connections (9) (10), the ratio of the instantaneous values of the quadrature components of the voltage of the stator 115, and Ugu according to the relation (12), which depends on the required the moment M, its rate of change, and the required frequency OJg.

In this case, the frequency of the stator voltage varies as the sum of the frequencies determined from (11) and (12):

WITH

Us

". +

I l. dt

(13)

The first component of the stator voltage, cOg, is equal to the frequency

rotor current coupling, changes synchronously with the magnetic field coupled to the rotor, and is therefore called the synchronous frequency. The synchronous frequency of the CO2 is the reference frequency for converting a synchronously rotating Cartesian coordinate system y, X into a fixed Cartesian coordinate system, B, with the fixed axis oi coinciding with the phase axis a of the three-phase stator winding a, b, c.

With this control method, a symmetric three-phase stator voltage, characterized by the spatial stator voltage vector Ug, is formed in Cartesian coordinates X, y synchronized by the required rotor flux-coupling frequency Q Q (j) M, which varies as a function of the measured speed (O, required the rotor flux link amplitudes proportional to the magnitude of the constant input action, and

The QVn phase and, consequently, the relative phase shift of the stator voltage and the rotor flux linkage does not regulate when the required torque is thrown and reset.

15 Enter the notation: K,

TO,

-2L; L / 3ZpL V (L; LS -, 20

transient inductance); Kj

 2R, / 3Z, v; 5 к,, / 3ZpL C;

Kf K, 2L; L, / 3ZpL (

,

((required amplitude of phase

the flux linkage of the rotor is proportional to the constant input of the required moment M, proportional to 25), and the operation on the voltage of the input control input voltage.

The adjustment in Cartesian coordinates x, at the phase shift angle of the spatial vector voltage of the stator U relative to the spatial vector of the rotor flux linking f is produced by adjusting the time vectors of the residual stator voltage Ug, 5 ,, Ug according to the law for instantaneous phase stator voltage in phase a

tori describe the direct analytical dependence of the instantaneous phase voltage of the stator in one of the phases, for example, phase o, as a function of the input voltage M of the speed W.

In polar coordinates, the instantaneous phase stator voltage

W and measured

35

Ug (t) is described by the equation

five"(

 H dt

 j (CJ + KjM) +), (14)

u (t) and

l coscfs-

where the clock phase qig is changed by changing the synchronous frequency col:

 H, - j o,; (t) dt - I «O.

M) dt,

and the stator phase voltage components V and Ug are projections of the spatial stator voltage vector in Cartesian coordinates, oriented along the y axis in the direction of the spatial rotor flux link vector.

This allows an instantaneous jump in the stator voltage phase by abruptly changing

5896212

projections that, when controlled in polar coordinates, affect only the magnitude of the stator voltage amplitude and the stator voltage frequency. A frequency jump does not lead to a phase jump, which is a disadvantage in controlling the stator voltage in polar coordinates, since the instantaneous Q phase and, consequently, the relative phase shift of the stator voltage and the rotor flux linkage does not regulate when the desired torque is dropped and reset.

15 Enter the notation: K,

TO,

-2L; L / 3ZpL V (L; LS -, 20

transient inductance); Kj

 2R, / 3Z, v; 5 к,, / 3ZpL C;

Kf K, 2L; L, / 3ZpL (

,

((required amplitude of phase

rotor flux linkage, proportional to the constant input effect), the operation on the voltage

tori describe the direct analytical dependence of the instantaneous phase voltage of the stator in one of the phases, for example, phase o, as a function of the input voltage M of the speed W.

In polar coordinates, the instantaneous phase stator voltage

W and measured

35

Ug (t) is described by the equation

five"(

 H dt

 j (CJ + KjM) +), (14)

where and is the instantaneous phase voltage amplitude, is equal to the quadrature sum of the two components of the stator voltage Ug sx

ABOUT

u |. ,

(15)

and the stator voltage Jg phase is formed only by a frequency sweep in 50 time:

Js j (with + K, M) +) dt. (t6)

55

In this case, a jump in the magnitude of the required moment leads to a jump only in the instantaneous amplitude Ug, but the phase of the Hv does not change in a jump.

Cartesian coordinates control the stator phase voltage

and, 1458962

jg (t) form according to law

fc

and .COS f (co + K M) - i Ug.sinJ (o + KjM),

(17)

5 up to me

5 additionally creates a force change in both the instantaneous amplitude of the stator voltage and its instantaneous phase at any change in the required torque M (t).

where the instantaneous amplitude of the phase voltage varies according to the same law (15), which is true for the polar coordinates of the control, but the instantaneous phase of the stator voltage

varies according to a different law and the jump-15 component varies both with a jump in the magnitude of the required moment M, as well as with any change in M (t) according to the law

f5 "(U + K M) dt +

The proposed method for controlling the stator strut in Cartesian coordinates in conjunction with the introduction

stator Ug. defined according to

20

v., c4upa SAin Compared with the expression O9), provides control of the instantaneous phase voltage of the stator in the dynamics and regulation of the phase shift of the stator voltage relative to the rotor flux linkage. As a result, invariant and inertialess control of the torque of the asynchronous motor is achieved, which improves the quality of speed control of the asynchronous electric drive closed in speed.

arct E

  K7 ((with TC m)

(18)

Presence of dynamic stator voltage

tol

Fi & 1

 Aich

 ,, dM

 b5g

(nineteen)

additionally creates a force change in both the instantaneous amplitude of the stator voltage and its instantaneous phase at any change in the required moment M (t).

The proposed method for controlling the stator voltage in Cartesian coordinates in conjunction with the introduction

 voltage component

stator Ug. defined according to

v., c4upa SAin Compared with the expression O9), provides control of the instantaneous phase voltage of the stator in the dynamics and regulation of the phase shift of the stator voltage relative to the rotor flux linkage. As a result, invariant and inertialess control of the torque of the asynchronous motor is achieved, which improves the quality of speed control of the asynchronous electric drive closed in speed.

at

s,

So

g / r.Z

Fi9.4

Claims (3)

1. A method of controlling an asynchronous electric drive, in which instant symmetrical phases are formed. voltage on the stator windings of an induction motor with amplitude, frequency and phase, depending on the measured rotation speed and two input influences, one of which is constant and corresponds to the required amplitude of the rotor flux linkage, and the other corresponds to the required moment, characterized in that, in order to improve the quality regulation by increasing the speed when monitoring the instant phase of phase voltages on the stator windings, form instantaneous symmetrical phase voltages on the stator windings according to time limit -Κ _α Μ * (ω + К ₅ М *) * M *) dtl - Κ ₄ Μ * + Κ ₅ ω к ^Kfo dt sin J (ω + K ₃ M *) dt. 0 where U _g (t) is the instantaneous phase voltage; four ' - a constant control action corresponding to the required amplitude of the rotor flux linkage; M * - control action corresponding to the required · * mu moment; G3 - measured rotation speed of an induction motor; To _A -K ₆ - constant coefficients, § determined by the parameters of the induction motor ί t - time. 2. A device for controlling an asynchronous electric drive, comprising a squirrel-cage induction motor, the stator windings of which are connected to the outputs of an autonomous voltage inverter connected to the control inputs with the outputs of the coordinate transformation unit, made with a control input in frequency and with the first and second control inputs in quadrature components of the stator voltage, series-connected speed controller, the first element of comparison, proportional-integral speed controller and a first adder, a speed sensor mounted on the shaft of an asynchronous motor with cage rotor connected to the output of a joint between the other inputs of the first comparison element and the first adder, multiplier unit, SU „„ 1458962 A1, the first input of which is connected to the output of the proportional-integral speed controller, and the output - with one of the inputs of the second comparison element connected by the other input to the output of the rotor initial linkage rotor, the second adder, the first input of which is combined with the second input of the multiplication unit , with the control input in frequency of the coordinate conversion unit and connected to the output of the first adder, the second input of the second adder through a scale element is connected to the output of the proportional-integral regulator and the speeds, and the outputs of the second comparison element and the output of the second adder are connected respectively to the first and second control inputs according to the quadrature components of the stator voltage of the coordinate transformation unit, which differs in that, in order to improve the quality of transients due to an increase in speed, an element is introduced differentiation, and the second adder is equipped with an additional third input connected to the output of the differentiation element, the input of which is connected to the output of the proportional-integral control speed speed. . 3. The device according to claim 2, characterized in that the coordinate conversion unit is equipped with a voltage-frequency converter, an address counter, first and second permanent memory blocks programmed according to the laws of sine and cosine, an adder block and four digital-to-analog converters, digital inputs of the first and the second of which are connected to the output of the first permanent storage unit, the analog inputs of the first and third, second and fourth digital-to-analog converters are paired the first and second control inputs respectively correspond to the quadrature components of the stator voltage of the coordinate conversion unit, the voltage-frequency converter input forms a control input by the frequency of the coordinate conversion unit, and the output is connected to the input of the address counter connected to the output with constant inputs memory blocks, the outputs of the digital-to-analog converters are connected ”to the inputs of the adder block, the outputs of which form the outputs of the coordinate transformation block.