SU936317A2

SU936317A2 - Reversible thyristorized ac switching device

Info

Publication number: SU936317A2
Application number: SU802988535A
Authority: SU
Inventors: Анатолий Анатольевич Сушенцов; Николай Петрович Чернов
Priority date: 1980-10-03
Filing date: 1980-10-03
Publication date: 1982-06-15

Description

Изобретение относится к электротехнике и может быть использовано в электроприводах промышленных механизмов.The invention relates to electrical engineering and can be used in electric drives of industrial mechanisms.

По основному авт. св. № 658685 известен реверсивный тиристорный коммутатор переменного тока, содержащий четыре пары встречно-параллельно соединенных силовых тиристоров и два трехобмоточных синхронизирующих трансформатора, первичные и вторичные обмотки которых соединены меж· ду собой соответственно начальными и конечными выводами, а третичные обмотки соединены параллельно через диоды, зашунтированы стабилитроном и связаны с узлами управления тиристорами, ограничители напряжения, два двухфазных мостовых выпрямителя, один из которых подключен зажимами переменного тока ко входным шинам пар встречно соединенных силовых тиристоров, а другой подключен к их выходным шинам, первичные обмотки син хронизирующих трансформаторов зашунтированы цепочками из последовательно включенных шунтирующих стабилитро нов и диодов, аноды которых соединены между собой и подключены к положительным полюсам двухфазных мостовых выпрямителей, а вторичные обмотки синхронизирующих трансформаторов зашунтированы цепочками из последовательно включенных шунтирующих стабилитронов и диодов, катоды которых соединены между собой и подключены к отрицательным полюсам двухфазных мостовых.выпрямителей [Ί ].According to the main author. St. No. 658685 known reversible thyristor switch AC, containing four pairs of in-parallel connected power thyristors and two three-winding synchronizing transformers, the primary and secondary windings of which are connected between each other respectively the primary and final terminals, and the tertiary windings are connected in parallel through diodes, shunted by a zener diode and connected to thyristor control nodes, voltage limiters, two two-phase bridge rectifiers, one of which is connected by terminals alternating current to the input busbars of pairs of oppositely connected power thyristors, and the other connected to their output buses, the primary windings of synchronizing transformers are shunted by chains of series-connected shunt zener diodes and diodes, the anodes of which are interconnected and connected to the positive poles of two-phase bridge rectifiers, and the secondary windings of synchronizing transformers are shunted by chains of shunt zener diodes and diodes connected in series, the cathodes of which are connected between themselves and are connected to the negative poles of two-phase bridge rectifiers [Ί].

Недостатком этого устройства является низкая надежность в связи С тем,' что при потере управляемости тиристоров возникают аварийные режимы работы тиристорного коммутатора и перегрузка источника питания.The disadvantage of this device is the low reliability due to the fact that when thyristors lose control, emergency operation of the thyristor switch and power supply overload occur.

Цель изобретения - повышение надежности работы реверсивного тиристорного коммутатора переменного тока.The purpose of the invention is to increase the reliability of the reverse thyristor AC switch.

Цель достигается тем, что в реверсивный тиристорный коммутатор переменного тока дополнительно введены две схемы совпадения и блок контроля ширины и блокировки управляющих им- 5 пульсов, вход которого соединен с выходом первой схемы совпадения и с одним входом второй схемы совпадения,' другой вход которой соединен с выходом блока контроля ширины и блокиров-ю кй управляющих импульсов, а выход соединен с входами узлов управления тиристорами, один вход первой схемы совпадения соединен с общей точкой катодов диодов третичных обмоток двух синхронизирующих трансформаторов, а другой вход предназначен для подклю чения к клемме управляющего входа.The goal is achieved by the fact that two matching circuits and a control unit for the width and blocking of control pulses of 5 pulses are added to the reversing thyristor AC switch, the input of which is connected to the output of the first matching circuit and to one input of the second matching circuit, the other input of which is connected to the output of the width control block and the blocking control pulses, and the output is connected to the inputs of the thyristor control nodes, one input of the first matching circuit is connected to a common point of the cathodes of the diodes of the tertiary windings of two syn drivers has a synchronizing transformer and another input is for Con cheniya to the control input terminal.

На чертеже показана блок-схема ; реверсивного тиристорного коммутатора переменного тока.The drawing shows a block diagram; reverse thyristor AC switch.

Коммутатор содержит четыре пары встречно-параллельно включенных тиристоров 1, 2, 3 и 4, два трехобмоточных синхронизирующих трансформатора 5 и 6, два двухфазных мостовых выпрямителя 7 и 8, подключенные соответственно ко входным и выходным шинам встречно-параллельно соединенных тиристоров, стабилитроны $ и 10, аноды которых подключены к положительным полюсам двухфазных мостовых выпрямителей 7 и 8, а катоды подключены к первичным обмоткам синхронизирующих трансформаторов 5 и 6, стабилитроны 11 и 12, аноды которых подключены к вторичным обмоткам синхронизирующих трансформаторов 5 и 6, а катоды подключены к отрицательным полюсам двухфазных мостовых выпрямителей 7 и 8, шунтирующие диоды 13, 14, 15 и 16, каждый из которых подключен параллельно последовательно соединенным обмоткам синхронизирующих трансформаторов 5 и 6, третичные об- ‘ мотки которых соединены параллельно через диоды 17 и 18 и зашунтированы стабилитроном 19, узлы 20 и 21 управления тиристорами, ограничитель напряжения 22, подключенный к выводам первичных и вторичных обмоток синхронизирующих трансформаторов 5 и 6, резисторы 23 и 24, каждый из которых подключен к выходу соответствующего • двухфазного мостового выпрямителя 7 и 8, схема 25 совпадения, один вход которой соединен с клеммой управляющего входа, а выход - со входом бло25The switch contains four pairs of on-parallel connected thyristors 1, 2, 3 and 4, two three-winding synchronizing transformers 5 and 6, two two-phase bridge rectifiers 7 and 8, connected to input and output buses of the on-parallel connected thyristors, zener diodes $ and 10 the anodes of which are connected to the positive poles of two-phase bridge rectifiers 7 and 8, and the cathodes are connected to the primary windings of the synchronizing transformers 5 and 6, the zener diodes 11 and 12, the anodes of which are connected to the secondary windings of syn synchronizing transformers 5 and 6, and the cathodes are connected to the negative poles of two-phase bridge rectifiers 7 and 8, shunt diodes 13, 14, 15 and 16, each of which is connected in parallel to series-connected windings of synchronizing transformers 5 and 6, the tertiary windings of which are connected parallel through diodes 17 and 18 and zener diodes 19 are shunted, thyristor control units 20 and 21, voltage limiter 22 connected to the terminals of the primary and secondary windings of synchronizing transformers 5 and 6, resistors 23 and 24, each minutes of which is connected to the output of the corresponding two-phase bridge rectifier • 7 and 8, the coincidence circuit 25, one input of which is connected to the control input terminal, and an output - to the input blo25

936317 4 ка 26 контроля ширины и блокировки управляющих импульсов и с одним входом второй схемы 27 совпадения, другой вход которой соединен с выходом блока 26 контроля ширины и блокировки управляющих импульсов, а выход со входами узлов 20 и 21 управления тиристорами.936317 4 ka 26 for controlling the width and blocking of control pulses and with one input of the second coincidence circuit 27, the other input of which is connected to the output of block 26 for controlling the width and blocking of control pulses, and the output with inputs of nodes 20 and 21 of thyristor control.

Устройство работает следующим образом.The device operates as follows.

В исходном состоянии почти все тиристоры 1, 2, 3 и 4 включены, по первичным обмоткам синхронизирующих трансформаторов 5 и 6 протекают импульсы тока длительностью 240 эл.град. (данная длительность достигается при незначительных габаритах синхронизирующих трансформаторов за счет включения параллельно вторичным обмоткам , ограничителя напряжения), следующие друг за другом через 180 эл. град. На вход узлов 20 и 21 управления поступает с третичных обмоток двух синхронизирующих трансформаторов 5 и 6 \ непрерывный сигнал. Поскольку команда в узлы управления на включение коммутатором не подана, управляющие ' импульсы на включение тиристоров 1, 2, 3 и 4с выходов узлов 20 и 21 уп! равнения не поступают.In the initial state, almost all thyristors 1, 2, 3, and 4 are turned on, current pulses of 240 el. Hail flow through the primary windings of the synchronizing transformers 5 and 6. (This duration is achieved with insignificant dimensions of synchronizing transformers due to the inclusion of a voltage limiter in parallel with the secondary windings), following each other through 180 el. hail. The input of the control units 20 and 21 receives a continuous signal from the tertiary windings of two synchronizing transformers 5 and 6. Since no command has been issued to the control nodes for switching on by the switch, control pulses to turn on the thyristors 1, 2, 3, and 4c of the outputs of nodes 20 and 21 are up! equalities do not arrive.

При подаче команды на включение двигателя один из узлов 20 или 21 разрешает выдачу управляющих импульсов на пары тиристоров 1 и 4 или на пары тиристоров 2 и 3 в зависимости от выбранного направления вращения электродвигателя. Во включенном состоянии тиристоров коммутатора напряжения на выходах двухфазных мостовых выпрямителей 7 и 8 равны и ток по обмоткам ' синхронизирующих трансформаторов 5 и не протекает.When giving a command to turn on the motor, one of the nodes 20 or 21 allows the issuance of control pulses for pairs of thyristors 1 and 4 or for pairs of thyristors 2 and 3, depending on the selected direction of rotation of the electric motor. When the thyristors of the switch commutator are switched on, the voltages at the outputs of the two-phase bridge rectifiers 7 and 8 are equal and the current does not flow through the windings of the synchronizing transformers 5.

При переходе тока той или другой фазы нагрузки через’ нуль тиристор закрывается. Это приводит к разбалансировке напряжений двухфазных мостовых выпрямителей 7 и 8 и в зависимости от фазы тока нагрузки к тем или иным обмоткам синхронизирующих трансформаторов 6 и 5 через один из резисто¹ ров 23 или 24 прикладывается линейное напряжение «сети.When the current of one or another phase of the load passes through zero, the thyristor closes. This leads to an unbalance of the voltages of the two-phase bridge rectifiers 7 and 8 and, depending on the phase of the load current, the linear voltage of the network is applied to one or another winding of the synchronizing transformers 6 and 5 through one of the resistors ¹ or 23 or 24.

При приложении напряжения к первичным обмоткам синхронизирующих трансформаторов 5 и 6, по сигналу ; со вторичных обмоток, узел 20 или 21 выдает импульсы на тиристоры, длительность которых будет равна времени включения тиристоров.When voltage is applied to the primary windings of the synchronizing transformers 5 and 6, by a signal; from the secondary windings, the node 20 or 21 gives out pulses to the thyristors, the duration of which will be equal to the turn-on time of the thyristors.

936936

Если же не включился один из тиристоров 1, 2, 3 и 4, то через определенное время единичным сигналом с выхода схемы 25 переключается выходной сигнал узла 26 контроля шири- ·⁵ны и блокировки управляющих импульсов с Г'.на ”0, отключается схема 27 и узлы 20 и 21 прекращают выдачу импульсов на тиристоры коммутатора. При этом исключается перегрузка элект·’® родвигателя, выходных элементов и источников питания.If one of the thyristors 1, 2, 3, and 4 does not turn on, then after a certain time the output signal of the width control unit · ^{5 5} and blocking the control pulses from Г'.na ”0 switches the unit signal from the output of circuit 25, the circuit turns off 27 and nodes 20 and 21 stop issuing pulses to the thyristors of the switch. This eliminates the overload of the electronic · '® motor, output elements and power supplies.

Такий образом, подключение третичный обмоток синхронизирующих трансформаторов к узлам управления через *^sсхемы совпадения и узлы контроля ширины и блокировки управляющих импульсов позволяет повысить надежность реверсивного тиристорного коммутатора переменного тока, так как производится автоматическое отключение тиристоров при возникновении аварийного режима работы.Thus, connecting the tertiary windings of synchronizing transformers to the control nodes through * ^s matching schemes and the nodes for controlling the width and blocking of the control pulses improves the reliability of the reverse thyristor AC switch, as the thyristors are automatically turned off when an emergency operation occurs.

Claims

The invention relates to electrical engineering and can be used in electric drives of industrial mechanisms. According to the main author. St. No. 658685 is known for an alternating current reversible thyristor switch containing four pairs of parallel-connected power thyristors and two three-winding synchronizing transformers, the primary and secondary windings of which are connected by themselves with initial and final leads, and the tertiary windings are connected in parallel through diodes, bridged a zener diode and connected to thyristor control nodes, voltage suppressors, two two-phase bridge rectifiers, one of which is connected to the terminals belt current to the input buses of pairs of oppositely connected power thyristors, and the other is connected to their output buses, the primary windings of the synchronizing transformers are shunted by chains of series-connected shunting zener diodes and diodes, which are connected to each other and connected to the positive poles of two-phase bridge rectifiers, and secondary windings of synchronizing transformers are shunted by chains of series-connected shunt zener diodes and diodes, the cathodes of which are connected They are interconnected and connected to the negative poles of two-phase bridge p. J. A disadvantage of this device is low reliability due to C. What is that if the thyristor loses controllability, emergency operation modes of the thyristor switch and an overload of the power source occur. Circuit out; gain - improving the reliability of the operation of the reverse thyristor AC switch. The goal is achieved by adding two matching circuits to the reverse AC thyristor switch and two control and blocking blocks for control pulses, the input of which is connected to the output of the first matching circuit and one input of the second matching circuit, the other input of which is connected to the output of the control contr the width and blocking of the control pulses, and the output is connected to the inputs of the thyristor control nodes; one input of the first coincidence circuit is connected to the common point of the cathodes of the tertiary coil diodes of two syn chronizing the transformer and the other input is intended to be connected to the terminal of the control input. The drawing shows a block diagram of a reversible thyristor AC switch. The switchboard contains four pairs of anti-parallel thyristors 1, 2, 3 and A, two three-winding synchronizing transformers 5 and 6, two two-phase bridge rectifiers 7 and 8, connected respectively to the input and output buses of anti-parallel connected thyristors, zener diodes (and 10, anodes of which are connected to the positive poles of two-phase bridge rectifiers 7 and 8, and cathodes are connected to the primary windings of synchronizing transformers 5 and 6, zener diodes 11 and 12, the anodes of which are connected to the secondary windings These are synchronizing transformers 5 and 6, and the cathodes are connected to the negative poles of two-phase bridge rectifiers 7 and 8, shunting diodes 13, k, 15 and 16, each of which is connected in parallel to series-connected windings of synchronizing transformers 5 and 6, whose tertiary windings are connected parallel through diodes 17 and 18 and shunted by a zener diode 19, thyristor control nodes 20 and 21, a voltage limiter 22 connected to the terminals of the primary and secondary windings of the synchronizing transformers 5 and 6, resistors 23 and 2k, each of which is connected to the output of the corresponding two-phase bridge rectifier 7 and 8, the coincidence circuit 25 one input of which is connected to the control input terminal, and the output - to the input of the control pulse width and blocking block 5 26 and one input of the second circuit 27, the other input of which is connected to the output of the block 26 for controlling the width and blocking of control pulses, and the output for the inputs of the thyristor control nodes 20 and 21. The device works as follows. In the initial state, almost all the thyristors 1, 2, 3, and A are turned on, current pulses with a duration of electra flow through the primary windings of synchronizing transformers 5 and 6 (this duration is achieved with minor dimensions of the synchronizing transformers due to the inclusion of a voltage limiter parallel to the secondary windings) following each other through 180 email. hail. The input of the control nodes 20 and 21 comes from the tertiary windings of two clock transformers 5 and 6 i a continuous signal. Since the command to the control nodes to turn on the switch is not applied, control pulses to turn on the thyristors 1, 2, 3 and k from the outputs of the control nodes 20 and 21 are not received. When giving a command to enable the drive, one of the nodes 20 or 21 allows the issuance of control pulses to thyristor pairs 1 and k. Or to thyristor pairs 2 and 3, depending on the chosen direction of rotation of the electric motor. In the on state of the thyristors of the voltage switch at the outputs of the two-phase bridge rectifiers 7 and 8, the current across the windings of the synchronizing transformers 5 and 6 does not flow. When a current of one or another phase of the load passes through the zero, the thyristor closes. This leads to the imbalance of the voltage of the two-phase bridge rectifiers 7 and 8, and depending on the phase of the load current, the linear voltage of the network is applied to one or another windings of the synchronizing transformer 6 and 5 through one of the resistors 23 or 2. When voltage is applied to the primary windings of synchronizing transformers 5 and 6, the signal from the secondary windings, node 20 or 21 pulses to the thyristors, the duration of which will be equal to the turn-on time of the thyristors. 5 If one of the thyristors 1, 2, 3 and if was not turned on, then after a certain time, the output signal of the width control and blocking control pulses from T switches to a single signal from the output of the circuit 25, the circuit 27 and the nodes 20 turn off and 21 stop the impulse impulse to the thyristors of the switch. This eliminates the overload of the electric motor, output elements and power sources. Thus, the connection of tertiary windings of synchronizing transformers to control nodes through coincidence scans and control widths and interlocking control pulses makes it possible to increase the reliability of the alternating current recirculating thyristor switch, as it automatically disconnects the thyristors when an emergency condition occurs. Claims of the invention Reversible thyristor AC switch according to aut. St. 7 "No. 658685, characterized in that, in order to increase reliability, two matching schemes and a width monitoring and blocking control pulses are added to it, the input of which is connected to the output of the first matching circuit and one input of the second circuit the other input is connected to the output of the width control block and the control pulses blocking, and the output is connected to the inputs of the thyristor control nodes; one input of the first cxef "9t match" is connected to the common point of the cathodes of the tertiary windings transformers, and the other input is intended to be connected to the control input terminal. Sources of information taken into account during the examination 1. USSR Author's Certificate No. 658685, cl. H 02 P 1LO, G977.