SU1072019A1 - A.c. voltage stabilizer - Google Patents

Abstract

AC VOLTAGE STABILIZER containing a booster transformer, the secondary winding of which is connected between the corresponding input and output terminals, the primary winding of one output is connected to the common bus, the other terminal is connected to one of the terminals of the controlled thyristor key, and the middle output through an uncontrolled key. controlled thyristor key and input terminal, two pulse drivers on transistors, the outputs connected to the control transitions correspond controlled thyristors, additional transformer. the primary winding of which is connected to the terminals for connecting the power supply, the measuring element ,. the input is connected to the output terminals, and the OUTPUT: with one input of the phase-matching node, the other input of which is connected to the synchronization node, and the output to one of the inputs of the corresponding driver: - / pulses, characterized in that, in order to increase reliability and improve mass-dimensional parameters, the phase-sensitive element is made of two transistors and two thyristor optrondx, and the bases of these transistors are connected through photo- S thyristors of optocouplers with the corresponding conclusions of the secondary maintenance system The middle transformer transformer emitters are combined, and the collectors are connected to other inputs of the corresponding pulse drivers, while the optocouplers LEDs through the input pulse driver J: are parallel to the controlled thyristor key.

Description

The invention relates to electrical engineering and can be used in the power supply of electronic equipment. A device is known that contains a main and booster transformers, two groups of parallel-connected thyristor switches, as well as a phase-sensitive element and a comparison unit, the outputs of which are interconnected and with corresponding semiconductor switches, the phase-sensitive element being designed as two measuring transformers , two null-organs and the AND logic, whose inputs are 1 through; the corresponding zero-organ is connected to the output of the measuring transformers.. The disadvantage of the device is the complexity of the device. The thyristor AC voltage regulator, containing a power transformer and uncontrolled and controlled semiconductor switches connected to the windings of a power transformer, which generate transistors impulses connected between control switches of an adjustable key, supplying transformer, synchronized with the power supply voltage, phase-shifting device and phase-sensitive element, made in the form of an opposite-series group of power diodes, V21 transistors and two voltage transformers G21. A disadvantage of the known device is the low reliability due to the presence of galvanic communication between the transistors. The phase-sensitive element and the power part, as well as significant weight and dimensions of the phase-sensitive element due to the use of diodes calculated at full load current. The purpose of the invention is to increase the reliability and improve the weight and size parameters. This goal is achieved by the fact that in an alternating voltage stabilizer containing a voltage transformer, the secondary winding of which is connected between the corresponding input and output terminals, the primary winding of one terminal is connected to the common bus, the other terminal to one of the terminals of the controlled thyristor key, and the middle the output through an uncontrolled thyristor switch is connected to another output of the controlled thyristor switch and the input terminal, two pulse shapers on transistors, outputs connected to to the pads of the respective thyristors of the controllable key, an additional transformer, the primary winding of which is connected to the terminals for connecting the power source, the measuring element, the input connected to the output terminals, and the output to one input of the phase-shifting node, the other input of which is connected to the synchronizing node, and output - to one of the inputs of the corresponding pulse generator, the phase-sensitive element is made of two transistors and two thyristor optocouplers, and the base of these trans The sources through the photothyristors of the optocouplers are connected to the corresponding pins of the secondary winding of an additional transformer, made with a midpoint, the emitters of the transistors are combined, and the collectors are connected to others. the inputs of the corresponding pulse shapers, while the LEDs of the optocouplers through the input of the input pulse shaper connected parallel. controllable thyristor key. The drawing is a schematic diagram of the device. The stabilizer contains a power boost transformer 1 with two adjusting pins, an unmanaged key on thyristors 2 and 3, and a control key on thyristors 4 and 5. The key control scheme on thyristors 4 and 5 contains pulse shapers 6 and 7, a phase-shifting unit 8 and a synchronizing node 9. The phase-sensitive element 10 is made in the form of transistors 11 and 12 and thyristor optocouplers 13 and 14. The basic transitions of transistors through photo thyristors 15 and 16 of thyristor optocouplers 13 and 14 are connected to the windings of the power transformer 17. LED thyristor photocouplers 13 and 14 through the input pulse generator 18 are connected in parallel thyristors 4 and 5 controllable key. The emitter-collector transitions of the transistors 19 and 20 of the formers B and 7 pulses are shunted respectively by the emitter-collector transitions of the transistors 11 and 12 of the phase-sensitive element 10. Phase-shifting node 8 is connected to the measuring element 21 connected to the output terminals. The device works as follows. In MOMejHT time i /, corresponding to the input current crossing over zero, the thyristor 2 is turned on and the booster transformer 1 is operated with a volt-residue. In this case, a positive polarity voltage appears on thyristors 4 and 5, which through the input shaper 18 opens the photo thyristor 16 of the thyristor optocoupler 14. In this case, the negative polarity voltage from the secondary winding of the supply transformer 17 through the photo thyristor 16 leads to a Bae-emitter the junction of transistor 12 and it locks. Thus, from the moment t, i, the operation of the pulse shaper 7 is possible. At time tj, depending on the magnitude of the error signal generated by the measuring element 21, phase shifting node 8 generates pulses for drivers b and 7. Synchronization of phase shifting node 8 with key operation is performed by synchronizing node 9 Since at time point -tj it is trans. zistor 12 is closed, and the transistor 11 from-. the control signal is generated only by the driver 7. and the inclusion of the thyristor 5, When the thyristor 5 is turned on, natural closing of the thyristor 2 occurs and the booster transformer 1 the remaining part of the current half-period works for the booster.

- At the beginning of the negative half-cycle, the input-current ode at time tj closes the thyristor 5 and turns on the Toop 3, the transformer operates with a voltage-residue. In this case, appearing.

on thyristors 4 and 5, the negative polarity voltage through the input shaper 18 opens the photo thyristor 15 of the thyristor ophron 13, the negative polarity voltage at the base-emitter junction of Transistor 11 closes it, which ensures that the thyristor 4 turns on from the former b at time point -fc pulse, pulse and change of work mode

0 booster transformer per booster. Further, the processes in the circuit proceed in the same way. The magnitude of the current (average) value of the output voltage is maintained as a stand-by due to time changes

5 work during each half period in one mode or another. The device can be either single phase or three phase.

0

By eliminating the galvanic coupling between the power section of the stabilizer and its control system, the reliability of the device a is improved.

5 elimination of power diodes from the system, designed for full load JTOK, improves the weight and dimensions.

Claims (1)

VARIABLE 'VOLTAGE STABILIZER, comprising a boost booster transformer, the secondary winding of which is connected between the corresponding input and output terminals, the primary winding is connected to a common bus with one terminal, the other terminal is connected to one of the terminals of the controlled thyristor switch, and the middle terminal is connected through the uncontrolled thyristor switch to the other terminal of the controlled thyristor switch thyristor switch and input terminal, two pulse shapers on transistors, outputs connected to ¹ control transitions of the corresponding t a controlled transistor, an additional transformer, the primary winding of which is connected to the terminals for connecting a power source, a measuring element, connected to the output terminals by the input, and the output with one input of the phase-shifting unit, the other input of which is connected to the synchronizing unit, and the output to one of the inputs of the corresponding pulse shaper, characterized in that, in order to increase reliability and improve overall dimensions, the phase-sensitive element is made on two transistors and two thyristor optocouplers, and the bases of these transistors are connected via optocouplers to the corresponding leads of the secondary winding of the additional transformer, made with a midpoint, the emitters of the transistors are combined, and the collectors are connected to other inputs of the corresponding pulse shapers, while the optocouplers LEDs are connected through the input the pulse shaper is connected in parallel with a controlled thyristor switch. fi ΓΟΖΖΟ Г “TiS