SU1310787A1 - Device for stabilizing a.c.voltage - Google Patents

Abstract

The invention relates to the field of electrical engineering and can be used in the power supply circuits of various equipment. The purpose of the invention is the expansion of functional capabilities by simultaneously stabilizing the phase and linear voltages in asymmetrical modes of operation. At the beginning of each half-cycle of the input voltage, a thyristor 7 or 8 is turned on, which ensures the operation of booster transformers 1–3 for a voltage-deduction, with a phase shift that is adjustable depending on the magnitude of the output voltage. From block 11, a thyristor 9 or 10 is turned on, which ensures a change in mode to the voltage additive. The formation of zero output by the windings of the three-phase autotransformer 15 provides an improvement in the shape of the output phase voltage curve, thereby achieving the goal. 2 3.p. f-ly, 1 ill. (L 00

Description

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The invention relates to electrical engineering and can be used in the power supply circuits of various apparatus.

The purpose of the invention is to expand the functionality by simultaneously stabilizing phase and linear voltages in asymmetrical modes of operation.

The drawing shows a diagram of the device.

The device contains a three-phase group of vertical addition transformers 1-3, the secondary winding 4 of which is connected in series with the load, and the primary windings 5 and 6 are connected to the semiconductors with the keys on the thyristors 7.8 and 9.10. Volt-to-base transformers 1-3 and thyristors 7-10 form a three-phase transformer-thyristor regulator. Thyristors 7-10 are connected to control unit 11. Three-phase av-transformer 15 is connected to output pins 12-14 with the first 16, second 17, third 18 and fourth I9 windings. The windings 16–17 are connected according to the ZIGZAG scheme, and the windings 18 are connected in opposite directions with the windings 17 and 16 of adjacent phases. Zero transistor 20 is formed by connecting the free outputs of winding 16 and is the output zero output. The fourth winding 19 of the autotransformer 15 is connected in series with the windings 4.

The device works as follows.

At the beginning of each half-cycle of the input voltage, the thyristors 7 or 8 are turned on, which ensures the operation of the booster transformers G-3 for the volt-residue, the voltage at the output of the device is less than the supply voltage. With a phase shift adjustable depending on the magnitude of the output voltage from unit 11, thyristor 9 or 10 is turned on. When opening thyristor 9 or 10, the direction of the magnetic flux is changed and, therefore, the mode is changed by the voltage boost. Thus, the output voltage of the device is maintained equal to the nominal.

Other algorithms of operation of semiconductor keys are possible, nats measures, when the keys are first turned on, which provide operation on the voltage add-on, and then with adjustable shift

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the keys that ensure the operation of the volt-auxiliary transformer per volt-deduction. In this case, fully controlled semiconductor 5 keys are used. Since the zero output for connecting the phase loads is the zero output of the three-phase autotransformer 15 windings included in the ZIGZAG, while stabilizing the linear (phase voltages), the phase (linear) voltages are simultaneously stabilized for forward and reverse sequence currents and low resistance for zero sequence currents.

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The proposed device also provides a significant improvement in the shape of the output phase voltage curve by reducing the third and 25-fold harmonics, and when the ratio of turns of the windings is 18.17 and 16 2: 1: 1, these harmonics are almost zero.

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Claims (3)

1. A device for stabilizing an alternating voltage containing a three-phase transformer-thyristor regulator with a control unit associated with the output phase terminals, characterized in that, in order to extend the functionality by simultaneously stabilizing the phase and linear voltages asymmetrical five 0 five operating modes, the device is equipped with a three-phase autotransformer containing the first and second windings interconnected according to the ZIGZAG scheme, the free terminals of the first windings are connected and form a zero output terminal, and the free terminals of the second windings are connected to the output terminals of the transformer-thyristor controlled organ and the output terminals .  2. The device according to claim 1, wherein the autotransformer is equipped with third windings, each of which is switched on in series with the first and second windings of adjacent phases. 3. The device according to p. 2, characterized in that The reformer is equipped with the fourth winding leads, the transformer included in accordance with the third histories of the regulator and the windings of the same phase between the outgoing output wires.