SU1418880A1 - Thyratron electric motor - Google Patents

Abstract

The invention relates to electrical engineering. The aim of the invention is to increase the energy performance by reducing current consumption and increasing the linearity of the adjustment characteristics. A tachogenerator I7 of direct current mechanically connected to the rotor 2 of the synchronous machine 1 and the modulator (M) 18 is inserted into the valve electric motor. Position sensor 10 (W) is equipped with a quadrature excitation winding 19. The output of the tachometer I7 is connected to the signal input M 18 , an input connected to the output of the source I2 of the reference voltage. The output M 18 is connected to the winding 19. As a result, the rotational speed of the valve motor is provided through the winding 19 of the PD 10. This allows for a delay in the control of the sinus 3 and the cosine 4 windings of the synchronous machine 1. Each control circuit is composed of interconnected phase-sensitive rectifier 15

Description

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QO OS

The invention relates to electrical engineering, in particular to electric motors, and can be used to control the frequency of rotation of an electric motor during continuous commutation.

The purpose of the invention is to increase the energy performance by reducing the current consumption and increasing the linearity of the adjustment characteristics.

The drawing shows a functional diagram of a valve motor.

The valve motor contains a two-phase synchronous machine 1 with permanent magnets on the rotor 2 and the core, sinus 3 and cosine A section windings, which are connected via power amplifiers 5 and 6, respectively, to the outputs of the first 7 and second 8 multipliers with two inputs. The first inputs of multiplication units 7 and 8 are connected to the output of the rotational frequency control 9. With the rotor 2, a position sensor 10 is kinematically coupled, the excitation winding 11 of which is connected to the source output.

12vorno .naprazheniya, and sine

13 and cosine 14, the output windings are connected to the second inputs of multiplication units 7 and 8, respectively, through phase-sensitive rectifiers 15 and 16. The reference inputs of phase-sensitive devices 15 and 16 are connected to the output of the source 12 of the reference voltage.

In addition, the electric motor contains a tachogenerator 17 of direct current and a modulator 18, and the rotor position sensor 10 is made with a quadrature excitation winding 19 connected to the output of the modulator 18, the signal input of which is connected to the output of the generator 17, and the reference input to the output of the source 12 of the reference voltage. The tacho generator 17 is kinematically connected with the rotor 2 of the synchronous machine 1.

The motor works as follows.

The reference voltage U is supplied from the AC source 12 and the voltage 1 of the rotational speed reference. Let us consider the case when the delay in the control circuits of a valve electric motor is negligible, i.e. and the voltage across the quadrature winding 19 is not energized. In this case, the windings 13 and 14 of the sensor 10 of the position form voltage 1, and, alternating current, the envelopes of which are separated by phase-sensitive rectifiers 15 and 16 as

. п г5 K ,, jK ,, A ,, sin0; ,, K, A ,,,

(one)

where K, is the transfer coefficient

phase sensitive rectifiers 15 and 16;

ol is the amplitude of the reference voltage Upf,;

e P Lf is the electrical angle, J, of the gate of the sensor 10 of the position and of the rotor 2 associated with it;

(- mechanical rotation angle;

P is the number of pairs of poles; K is the transformation coefficient of the position sensor 10 on the side of the main excitation winding 11.

Then blocks 7 and 8 of the multiplication form output voltages, which, after amplification in amplifiers 5 and 6, go to the sine 3 and the cosine 4 windings of the core of the synchronous machine 1 as

UJ-KS K, GK „A„ „and, sine; (2) U4-Kt K, K, A, “U, cose,

where - the transmission coefficient of the amplifiers 5 and 6 power. Since in this case it is assumed that the time inductance of the core winding is constant can be neglected and the currents in the windings 3 and 4 have the form

,, sine; cose,

(3)

4 with V

where ,, K, A, JE;

R is the active resistance of the windings 3 and 4,

In accordance with the principle of the valve motor, the currents ij and i form the magnetomotive force (MDS) of the stator, the interaction of which with the MD (the rotor leads to the appearance of a torque that causes rotation of the rotor e 2 with a frequency H proportional to the amplitude of the stresses on the sine 3 and cosine 4 windings core

3U

I -k. MAz-k, and ,, (M

where constructive parameter of synchronous machine 1;

  op

At the same time, as follows from (3), the coefficient K {; and the phases of the currents in the winding sections of the core do not depend on the rotation frequency, therefore such a valve motor has optimal characteristics and does not need to enter the switching angle p. This is a consequence of the lack of spanning in the control circuits (),

If there is a delay in real control circuits, i.e. at Tk Oh, to optimize the characteristics of a valve electric motor, it is necessary to introduce a switching angle ft

To introduce the switching advance angle, the rotational frequency R of the rotor 2 is measured by a tachogenerator 17, transformed by a modulator 18 into an alternating current voltage U, gH, and applied to the quadrature winding 19 of the sine-cosine rotating voltage transformer.

, jK ,, fl, (5)

 where K JJ and K, - transfer coefficients

modulator 18 and tacho generator 17, respectively.

When powering two mutually perpendicular windings 11 and 19 of the excitation voltage in the windings 13 and 14. sine-cosine rotary transformer in accordance with its principle of action are equal

, Uon sine -K ,, and „COS0; ,,. ,, and „soe + K ,, U, jSin e,

where K, - transformation ratio

sensor 10 position on the side of the quadrature winding 19 excitation.

Phase-sensitive devices 15 and 16 make envelopes of these voltages

,, j (K ,, AonSine -VJ (K ,, + K,

. „„ Sine, c6s9);

. „Cose + K ,, u, 5sine)

(7

where U, j is the amplitude of the voltage envelope and f.

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When deriving relations (), Phase-sensitive rectifiers 15 and 16 are assumed to be inertia-free, and their delay, included in the common time constant T, is conventionally related to the time constant of the power amplifiers 5 and 6 and the windings of the synchronous machine core 1,

1Q Using the known trigonometric relations, expressions (7) transform:

15

U, j —A sin (e-p); U, t And cos (e-),

(eight)

where f, is the switching angle,

, 9 arctg --- 1 - and „; (9)

 l rp.

20 .K, K ,, f7 | i.

(ten)

After blocks 7 and 8 multiply the signals are equal

U-, AU.jsin (0 -p); ,, cos (e- (3),

(ten

Further, these signals pass through power amplifiers 5 and 6 and are converted into currents ij and i of sections 3 and 4 of the winding box.

In these nodes, all the control circuit lags are concentrated, which can be taken into account by the transfer function with a constant time T, having, for example, for section 3 of the winding core

 ( 12)

W3 (P) |,.

40 where,

R - section resistance; P - Laplace operator,

In accordance with the properties of transfer functions, the amplitude of the current in section 3 is equal to

(13)

I3 U7 / W3 (J). and its phase is shifted by the angle V 50 v-arpb), (U)

where U-, A-Uy is the voltage amplitude at the input of amplifier 5; (Wj (ju)) I - amplitude-frequency characteristic (AFC);

arg Wj (ju)) - phase response characteristic (PFH);

and) :: p L - frequency of the signal at the input of the amplifier 5.

Frequency response and phase response transfer function 512) are equal

| W (JU5) |

TO,

iurV

arg Wj (Juj) arctg You.

Therefore, taking into account (P) the current in section 3 of the winding core takes the form

i3-KcU ,, sin (6- / s + v). (15)

Similarly for current in section 4

i ,, KcU ,, cos (e- (5 + V), (16)

1Д18880 (,

(H)., I.e. the effect of lag in the control circuit is eliminated.

Thus, the introduction of feedback 5 according to the frequency of rotation of the valve electric motor through the quadrature excitation winding of the position sensor makes it possible to compensate for the delay in the control circuit at any frequency of rotation. This leads to an increase in the linearity of the adjustment characteristics and an increase in the energy performance by reducing the current consumption.

15

Claims (1)

Invention Formula Invention Formula Where  , AOP r.7Kt9Ui8 P2 V arctg Tif-i. Taking into account 5, and also taking into account the expression (l) RP, transform expressions (17), (18) and (9) 25 K lb lf: i il- Ji + ())  Vl + TVp P1 1 op .ii) it arctg (arctp K (K igKt7 I, From expressions (19) - (21) it follows that in the general case the valve motor under consideration does not have optimal characteristics, since the phases of the currents () of the sections and the coefficient S1. However, if you select the parameters of the valve motor from the ratio Valve motor with / jy-j holding a two-phase synchronous machine with permanent magnets on the rotor and the core, sine and cosine winding (Q on the sections of which are connected respectively through power amplifiers to the outputs of the first and second multiplication units with two inputs, the first inputs of which are connected to the output of the rotational speed sensor, kinematically connected to the synchronous rotor machines, winding 30, whose excitation is connected to the output of the voltage source, and the sine and cosine output windings are connected respectively to the second inputs of the multiplication units via 35 phase-sensitive rectifiers, the reference inputs of which are connected to the output of the source of the reference voltage, characterized in that, in order to increase the power inputs by (20) (21) Kj. depends on the frequency of the turnaround by reducing the current consumption and increasing the linearity of the characteristics; a tachogenerator of the direct current and a modulator are introduced, and the position sensor is made with a quadrature excitation winding connected to the ti -t output of the modulator; which is connected to the output of the generator and the reference input to the output of the source of the reference voltage, and the tachogenerator is kinematically connected with the rotor of the synchronous machine. .5G TR K Apr, then, as follows from (19) - (21), K ,, 5K ,, A, const ,. Therefore, expressions (15) and (currents of sections 3 and A accept 16) view (22) (23) for 50