SU1429256A1 - Device for separate control of reversible thyristor converter - Google Patents

Abstract

The invention relates to electrical engineering and coins to be used in thyristor converters. The purpose of the invention is to increase the reliability. When the current is interrupted, the pickup signal on v: sensor 1 is zero. Transistor 15 closes and transistor 19 opens and the pulses are removed without delay. Capacitors 25 and 26 provide for switching the reference to an on-delay. another group. When pulses pass through resistor 27 (28). On g collector of transistor 19 (20), a blocking potential is created, which excludes the possibility of switching on the transistor | 1 of stack 16 (15) and simultaneous impulses to the anodic and cathodic groups of 1 or o-fft ( L S

Description

The invention relates to electrical engineering and can be used to control the switching of the anodic and cathodic groups of thyristors of a three-phase reversible thyristor converter with separate control,

The purpose of the invention is to increase the reliability of the converter. I The drawing shows a diagram of the device.

I Separate control device (it contains a thyristor sensor 1 of conducting states containing 1sontrol voltage on thyristor pairs) 2-5 connected to phases A, BjC Power circuit voltage, blocks 6 and 7 () sign limits signal set jroKa, element OR diodes 8-10, times) | The common diodes are 11-14, a logical switching unit with transistors 15 and 16, the first 17 and second 18 stabilitrons, the transistors 19 to 20 output keys, the third 21 and a quarter

22 stabilizers and executive elements 23 and 24, capacitors 25 and 265 shunt collector circuits - the base of transistors 19 and 20, resistors 27-34, diodes 35 and 36

The device works as follows.

In the absence of a task signal to turn on any thyristor -: group (the output of blocks 6 and 7 is voltage, for example 5-12V), transistors 15 and 16 of the logical switching unit are also locked to the bases of transistors 19 and 20 of the output keys via zener diodes 17 and 18, a positive voltage is applied, their base — a smitter — current flows sufficient to saturate them at a maximum collector current. Accordingly, the input voltage of the actuators

23 and 24 is zero, and they remove all control pulses from the thyristors.

When specifying the inclusion of one of the converter groups (for example, block 6 pushes 12 V), transistor 15 is open due to flow

ten

circuit current: decoupling diode and base, emitter, diode 36, collector - emitter of transistor 20. Output key transistor 19 is also locked when its voltage is on its collector, which supplies the voltage of the third zener diode 21, the actuator 23 allows for impulse output . The output of the OR element performed on

For years 8-10, a pickup voltage appears, holding the transistor 15 in the open state as long as at least one thyristor is open. If there is a pickup, switching the reference signal to block 7 does not affect the operation of the circuit; T; IK as a current circuit to open transistor 6 is locked with a closed transistor 19,

When the current is interrupted, the pickup signal of the output of the sensor I becomes zero, the transistor 15 closes, which causes the output switch transistor 19 to open and the pulses are removed with almost no delay time delay. The capacitors 25 and 26 provide when switching the job delay on the inclusion of another group. The delay time is determined by the capacitor capacitor 25 (26), the voltage of the Zener diode 21 (22), and the resistance of the resistor 27 (28). The introduction of the delay is achieved with a minimum of additional elements and a super; 1, notably, the noise immunity and reliability of the device operation.

When the pulses pass through the resistor 27 (28), a collector is created at the collector of transistor 19 (20): a potential that naggingly excludes the possibility of switching on the transistor 16 (15) of the logic switch, the y-switch and the pulse to the cathode and anode groups of the thyristors at the same time. The introduction of the indicated locking potential and threshold elements increases the interference and eliminates the simultaneous impulses to the cathode and anode groups, even if the logical switch of the transistors of its unit fails.

Thus, the use of the proposed device ensures the reliability of the operation of a reversible converter with separate control

Claims (1)

Invention Formula A device for separate control of a reversible thyristor converter containing a thyristor conducting state sensor, a master signal setting unit, four decoupling diodes, two resistors, a logical switching unit on two transistors and two output transistor switches for controlling the converter thyristor groups. characterized in order to increase the reliability of the converter, the driver of the master signal is made in the form of two blocks for determining the sign of the signal of the current command signal, and the device is equipped with four zener diodes, six resistors, two diodes and two capacitors, and the outputs of the conductive sensor and blocks determining the sign of the current setting signal through the first and second resistors and developmental diodes are connected to the transistor base of the logic switching unit, their collectors are connected via the third and fourth resistors to the first power bus, and through the first and second zener diodes to the bases of the transistors of the output switches, the emitters of the transistors of the logical switching unit are connected through the first and second diodes to the collectors of the output keys, the bases of the transistors of the output switches are connected to the second power bus common point, collectors through fifth and the sixth resistors are connected to the first power bus, the first and second capacitors are connected between the bases and collectors of the output switch transistors, and the third and fourth stabilitrones are used to connect Ik to the output switch collectors of the output thyristor control blocks of the anode or cathode converter group.