SU904089A1 - Thyristorized converter with protection - Google Patents

Description

I

This invention relates to thyristor converters.

A device for protection of a thyristor converter is known, which contains thyristor current sensors connected to the inputs of the circuits unequally. the second inputs of which are connected to the outputs of the counting unit, the BAN AND OR P. schemes

A disadvantage of this device is complexity.

The closest to the proposed technical essence and the achieved result is a thyristor converter with protection, working with a master oscillator, containing thyristor current sensors, connected to the inputs of the OR circuit and the AND circuit, the outputs of which are connected to the display unit, and the time selector associated with the protection executive body 21.

A disadvantage of this device is low reliability.

The purpose of the invention is to increase reliability.

Claims (2)

The goal is achieved by the fact that the device is equipped with two pulse shapers, an unequal element and inverters, and the AND circuits are combined into two blocks, with the first and second irregularity element inputs connected to the generator and OR outputs, respectively, and the output of the unequality element the input of the selector, the output of which is connected to the executive body and with the first inputs of all the And circuits, the second inputs of the And circuits of the first block through inverters, and the second block directly connected The sensors are connected to the sensor outputs, and the third inputs of the AND blocks of the first block are directly connected, and the second block is connected via an inverter to the output of the first one. spinner The drawing shows a block diagram of the device. The device contains sensors 1-6 of current, thyristors of a three-phase bridge converter connected to sensors OR 7, shaper 8 pulses connected to a common generator 9, shaper 10 pulses connected to an element OR 7, element II unequal in value, connected to shapers 8 and 10, time selector 12, actuator 13, block 14 of elements NOT (inverters), first and second blocks 15 and 16 of elements AND, and block 17 of the display, connected 1st to outputs of elements AND. The device works as follows. During normal operation of the converter at the outputs of sensors 1-6, pulses of a single logical level are formed when conductive and zero when the non-conducting state of the thyristors. Shaper 8 generates pulses at the front of the generator 9 pulses, shaper 0 generates pulses of the same duration as the shaper 8. Because pulses simultaneously arrive at the input of element I1, there are no signals at its output. If the edges of the shaper 8 and 10 do not match, For example, due to the delay of the pulse from the output of the element 7 relative to the pulse of the generator 9, the output of the element 1I contains signals that the selector 12 serves to exclude. In the case of non-switching, for example, the thyristor to which the sensor 1, there will be no pulse at the output of element 7, one signal will go to the input of element 1I, and not two, and the signal element 13 will come through the selector 12 from the output of element 1I. At the same time, after the input element 15 of the element I coincides with the signal of element NOT block 14 and the signal of the imaging unit 8 is fed to the input of the block 17. If a spontaneous switch-on occurs, for example, a thyristor to which the sensor 6 is connected, then the second input of element 1I comes from element 7 through the imaging device 10 and the first input of element II no signal is received. The signal from the output of element 1I through the time selector 12 enters the organ 13 and the first inputs of block I of elements, where after the signal of the selector 12 coincides with the signal of the element NOT of block 14 and with the signal of sensor 6, the signal arrives at block 17. The device has an increased reliability Claims of the invention A thyristor converter with protection operating with a master oscillator, containing thyristor current sensors connected to the inputs of the OR circuit and the AND circuit, whose outputs are connected to the display unit, and a time selector associated with the protection executive body, due to the fact that, in order to increase its reliability, it is equipped with two pulse shapers, an inequality element and inverters, and the AND diagrams are combined into two blocks, with the inputs of the unequality element through the first and second drivers connected to the outputs of the generator and the OR circuit, respectively, and the output of the inequality element is connected to the input of the selector, the output of which is connected to the executive body and to the first inputs of all the And circuits, the second inputs of the AND blocks of the first block through the inverters and the third inputs of the circuits AND of the first block are directly, and the second block is connected via an inverter to the output of the first driver. Sources of information taken into account during the examination 1. USSR author's certificate No. 698099, cl. And 02 And 7/10, 1978. 2. USSR author's certificate for application No. 2501166 / 24-07, cl. H 02 H 7/10, 1977.