SU1352608A1 - Method of exciting pendulum oscillations of rotor of two-phase induction motor - Google Patents

Abstract

The invention relates to the control of electrical machines and can be used to create oscillating actuators. The purpose of the invention is to increase the amplitude of oscillations. A connection is made to the first 12 windings of the electric motor of the positive half waves of the first 2 and second 3 secondary windings of the transformer. Then, with a half-shift, the negative half-waves of the first 2 and second 3 secondary windings of the transformer are connected to the second winding 13 of the electric motor. Then, with a half-shift, the negative half-waves of the first 2 and second 3 secondary windings of the transformer are supplied to the first winding 12 of the electric motor. With a shift by half a period, the negative half-waves of the first 2 and second 3 secondary windings of the transformer are supplied to the second winding 13 of the electric motor. Subsequently, with a half-period shift, the indicated half-wave connection sequence is repeated. 3 il. (L

Description

This invention relates to methods for controlling electrical machines and can be used to create oscillating electric drives.

 The purpose of the invention is to increase the amplitude of oscillations.

FIG. Figure 1 shows a graph of alternating half-waves of a single-phase secondary voltage of a split first and second phase; in fig. 2 - power circuit diagram; Fig 3 is a block diagram of the control system. In order to excite the rotor oscillations of a two-phase asynchronous electric motor, power is supplied from the anti-phase voltage obtained using a single-phase transformer with two secondary windings with opposite winding.

According to FIG. Figure 1 determines the beginning of the positive half-wave of the first secondary winding of the transformer, falling in phase with the supply voltage, and connecting it to the first winding of a two-phase asynchronous electric motor at this moment. After that, at the moment of transition of the first positive half-wave through the zero, the second secondary winding of the transformer is connected to the first winding of a two-phase asynchronous electric motor and simultaneously the first secondary winding of the transformer to the second winding of a two-phase asynchronous electric motor. When the negative half-voltage of the first secondary winding of the transformer passes through zero, the second secondary winding of the transformer is connected to the second winding of a two-phase asynchronous electric motor. When currents flow in both phases of the asynchronous electric motor, an electromagnetic moment develops, which causes the shaft to turn at a certain angle. Subsequently, when the positive half-wave goes over the voltage of the first winding through the zero, a negative half-wave of this voltage is applied to the first winding of the two-phase asynchronous electric motor. At the moment of transition of the negative half-wave voltage through zero, the second secondary winding of the transformer is connected to the first and second windings of the two-phase asynchronous electric motor and then when switching over the positive half-wave voltage

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The secondary winding of the transformer supplies the negative half-voltage of the first secondary winding of the transformer to the second winding of a two-phase asynchronous electric motor. In doing so, the motor shaft turns at a certain angle in the other direction. In the future, alternate the connection of the first and second secondary windings of the transformer to the first and second phases of a two-phase asynchronous motor in the specified sequence. A rocking magnetic field is formed with a modulation period equal to three periods of the single-phase supply voltage. As a result, steady-rotated oscillations of the rotor of a two-phase asynchronous electric motor are excited,

A device that implements the method contains a single-phase transformer — with primary winding 1 and two secondary windings — the first secondary winding 2 and 5 and the second secondary winding 3 — which have a common point, which are connected via thyristors 4–11 that form phase paired switches to the first winding of a two-phase asynchronous motor 12 and the second winding of a two-phase asynchronous motor 13 (Fig. 2)

In the block diagram of the control system (Fig. 3), to the input of the trigger 14, which fixes the single-phase secondary voltage of the first secondary across zero from negative values to positive, the trigger1 and 1-5, which fixes the single-phase secondary voltage of the first secondary voltage is connected Winding through zero from positive values to negative. Switches 16 and 17 are connected to a 1K-trigger 18. Output 1K of a trigger 18 is connected to a pulse shaper 19 connected to a control transition of the thyristor 4. At the output of the 1K flip-flop 18, a single vibrator 20 is also connected, the output of which is connected to an And 21 element connected with the trigger 15. To the output of the element 21 are connected to the formers 22 and 23 of the pulses connected to the control transition of the thyristors 6 and 9, respectively, as well as; to the one-oscillator 24. The outputs of the one-oscillator 24 and trigger 14 are connected to the input of the element I 25, at the output of which the driver 26 is mounted

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and the one-shot 27. At the output of the single-vibrator 27, an element 28 is connected, connected to the trigger 15. At the output of the element 28, a pulse shaper 29 is connected, connected to the control transition of the thyristor 5 and one new vibrator 30. At the output of the one-wave 30 31, connected to the trigger 14, which fixes the transition of the voltage of the first secondary winding of the transformer through zero from negative to positive values. A pulse shaper 32 and 33 pulses are connected to the output of the element 31 and connected to the control transitions of the thyristors 7 and 8, respectively, as well as the one-shot 34. the element 35 is connected to the output of the one-shot 34, which is connected to the trigger 15, which fixes the voltage of the first secondary transformer through zero from positive to negative. A pulse shaper 36 connected to the thyristor control transition 10 and a single vibrator 37 are connected to the output of the element 35. At the output of the one-vibrator 37 an element 38 is installed connected to the trigger 14. The output of the element 38 is connected to the driver 19 of the pulses and the one-vibration 20 To, the input of the switch 39 connected to the input of the trigger 15 is connected, a voltage divider 40 connected to the first secondary winding 2. The source 41 is connected via the switch 16 to the trigger 18. All single vibrators have a pulse expansion period of more than one half The period of the supply voltage. All triggers, single-oscillators and components are powered by AND from individual sources.

The diagrams of FIG. 2 and FIG. 3 act as follows.

With the help of the switch 16, the 1K-trigger 18 is reset. When the voltage of the half-wave voltage of the first secondary winding of the transformer goes from negative to positive, if the switches 17 and 37 are closed, trigger 14 and 1K-trigger 18 are triggered, which triggers pulse generator 19 in the thyristor control circuit 4. Simultaneously, 1K-trigger 18 starts a single vibrator 20. When triggering a trigger 1 5 and having a pulse from the one-shot 20, triggers element I 21 and

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triggers shapers 22 and 23 pulses in the control circuits of thyristors 8 and 7, as well as the one-shot 24. If there are input signals And 25 from the trigger 14 and one-shot 25, the driver 26 pulses in the control circuit of the thyristor 11 and. when the one-shot 27 and the trigger 15 triggers, the element 28 turns on the driver 29 of the pulses in the control circuit of the thyristor 5 and starts the one-shot 30. Then, if signals from the one-shot 30 and trigger 14 are present, the element 31 turns on and starts the drivers 32 and 33 pulses in thyristor control circuits 9 and 11. respectively, as well as the one-shot 34. When pulses from the one-shot 34 and flip-flop 15 appear, the driver of 36 pulses in the control circuit of the thyristor 11 and the one-shot 37 operate. When pulses from the one-shot of 38 and trigger 14 trigger, the And 38 element starts the driver of pulses 19 in the control circuit thyristor 4 and one-shot 20. In the following, the cycle is completely repeated.

Owing to an increase in the duration of the phase supply, the amplitude of gentle oscillations increases.

Claims (1)

Formula isobteni A method of exciting rotor oscillations of a two-phase asynchronous motor, including connecting the motor phases to a power source for a predetermined number of single-phase voltage half-cycles and shutting them off when the phase currents pass through zero, which in order to increase the amplitude of oscillations, the source voltage is inverted power supply; the first positive half-voltages of the power supply and the inverted power supply, the second negative half-voltage of the power supply and tert are applied to the first phase th inverted negative half-wave voltage is fed to the second phase of the first and third negative half-wave voltage power supply and second and third negative half-wave of the inverted voltage, and after three periods, the power supply voltage is repeated these operations. fzl F n P ; 7 8 Schfig .Z