SU1744770A1 - Former of powerful control pulses - Google Patents

Abstract

Summary of the Invention: when a triggering pulse is applied to the control electrode of the thyristor switch 3, the capacitors 4 and 5, pre-charged from the power source 1, are discharged through the inductor 7 and the resistor 8, respectively, to the load terminals 9, generating a powerful control pulse. Simultaneously with the supply of the triggering pulse to the thyristor control electrode, the control unit 14 generates a pulse that triggers the transistor 13. The current flowing from the additional constant voltage source 11 through the resistor 12 and the transistor 13, reduces the leading edge current. control pulse 2 sludge. co y h xj vj o zig1

Description

The invention relates to a converter technique and is intended to control single-operation thyristors and valves consisting of a group connection of such thyristors.

Devices for generating control pulses are known in which attempts are made with additional elements to increase the steepness of the output pulses.

However, the non-linear segment at the initial stage is not completely excluded, despite the complexity of the devices, and the steepness is insufficient. Especially important is the high steepness of the control pulse to ensure maximum resistance of the power thyristors to the anode current rise rate and for the series connection of high-speed power thyristors without shunt RC circuits at higher frequencies.

A device for controlling a two-stage thyristor is known, in which the largest control pulse is formed of negative polarity for locking the two-stage thyristor and interrupting a constant anode current. This pulse is generated when the auxiliary thyristor is turned on in the device. The indicated two-stage thyristor is switched on by a smaller control pulse of positive polarity due to the dose of the storage capacitor after the transistor is closed and the transistor is reopened.

The supply of a control pulse of negative polarity to a single-step thyristor is not necessary and harmful, since this thyristor cannot interrupt the direct current and it is impossible to lock such a thyristor, but can only be turned on. In this case, it is necessary to pay special attention to the leading edge of the control pulse, so that the properties of the power thyristors and their assemblies do not sharply deteriorate.

The purpose of the invention is to reduce the duration of the leading edge of the output pulses and enhance the functionality.

The goal has been set to form a powerful positive control impulse for switching on a single-operation power thyristor (s), eliminating the growth delay of the control impulse and reducing the duration of its leading edge.

FIG. 1 and 2 are diagrams of the device.

FIG. 1, the output generated pulses (Cl. 1 and Cl, 2) are fed directly to the power thyristor 10, and FIG. 2 - are fed through cable current transformers to a valve consisting of a group (series) connection of 10.1-U power thyristors.

To the source 1 through the limiting resistor 2 is connected the anode of the auxiliary thyristor 3 and the capacitors 4 and 5 of the switching RC- and LC-circuits b connected in parallel, which are connected to load cell 1. The cathode of the auxiliary thyristor 3 is connected to the second end

load 9 (Cl. 2), as well as with the negative pole of source 1 and the positive pole of the second source 11. The negative pole of source 11 through the limiting resistor 12 and the transistor

13 is connected to the load 9 (Cl. 1). The auxiliary thyristor 3 and the transistor 13 from the source of primary pulses (control unit) 14 are simultaneously pulsed, and the pulse duration

control to the transistor 13 corresponds to the turn-on time of the auxiliary thyristor 3. The position 7 denotes the inductor, the position 8 denotes a resistor.

The shaper of powerful control pulses operates as follows.

When voltage is applied from source 1 through limiting resistor 2 and load 9, capacitors 4 and 5 of circuit 6 are charged. When pulses are supplied from block 14

control to the auxiliary thyristor 3 and the transistor 13 on the load 9, the currents from the circuits 6 and the source 11 are summed up. Therefore, the nonlinear initial part of the output control pulses on

the power thyristors are completely eliminated due to the turn-on delay time of the auxiliary thyristor 3. The presence of the LC circuit in the circuits b and a sufficient value of the resistor 2 leads to the cessation of current through

auxiliary thyristor 3 and to charge capacitors 4 and 5 of the circuit 6.

The use of the proposed device provides a high linear steepness of the output control pulse.

for turning on the power thyristor 10 or the valve consisting of a group connection of power thyristors 10.1-10.

Claims (1)

As a result, the difference in the turn-on delay time of successively connected power thyristors is reduced, and the resistance of these thyristors to the anodic current rise rate increases, the claims of the invention Power generator of control pulses containing a control unit the first input of which is connected to the control circuit of the transistor, and the second is connected to the control electrode of the thyristor switch connected in series with the first limiting resistor between the power supply terminals, and the forming circuit, the first output of which is connected to the first power output of the thyristor switch, the second power output of which is intended for connecting to one of the load terminals, for connecting to the other output of which a second output of the forming circuit is intended, characterized in that, in order to reduce the elnosti the leading edge of the output pulses and the functionality extension 0 five capabilities, a second limiting resistor and an additional DC voltage source are connected in series with a second limiting resistor and a transistor between the second power output of the thyristor switch and the second output of the forming circuit, made in the form of consecutive RC and LC circuits, the extreme outputs of which are combined and used as the first and second outputs of the forming circuit, and the control unit is made that provides simultaneous supply of trigger pulses to the control circuit anisistor and thyristor key control electrode. CL one  o-i 9 CL.G BUT Yu.P iro w Shg.1