SU1390732A1 - Device for controlling thyristors of a reversible transducer - Google Patents

Abstract

The invention relates to electrical engineering and can be used in reversible transducers with separate control. The aim of the invention is to increase the reliability and speed of the reverse. Introduction to the device of shapers 11, 12 short pulses connected to the antiphase outputs of the switch 9, and the execution of amplifiers 5 and 6 pulses with two-pole pulses allows reliable locking of the conducting group 1 or 2 of the reverse thyristor during current reversal. This makes it possible to reduce the delay for the inclusion of another group of thyristors, which leads to an increase in the speed of the reverse. The sensitivity of the sensor 4 can be reduced. 1 il.

Description

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; The invention relates to electrical engineering and can be used in reversible converters,

; The purpose of the invention is to increase the reliability and speed of the reverse,

The drawing shows a diagram of the device.

The power circuit of the converter is composed of groups 1 and 2 of thyristors, the number of which is usually three or six (three-phase zero or bridge I), and a single-line diagram is shown to simplify the drawing. Groups 1

2 form two rectifiers, with the switch unlocking another block 8 or 7.

and

opposite poles in parallel, a load 3 with current sensor 4 is connected to the poles of the rectifiers, two-pole amplifiers of 5 and 6 pulses are connected to the control inputs of groups 1 and 2, the circuits of which are the same. Blocks 7 and 8 of pulse-phase control — groups 1 and 2 of different directions are connected to the triggering inputs of short pulse shapers. The blocking (locking) inputs of blocks 7 and 8 are connected to the output of logic switch 9, which is connected to the output of sensor 4 by an input. The control inputs of control signal 10 are connected to the control inputs of blocks 7 and 8. To the inputs of the Negative polarity of amplifiers 5 and 6 are connected to the formers of 11 and 12 pulses on the signal front.

As an example, the amplifier circuit 5 is shown in expanded form. It contains two pulse transformers 13 and 14, the secondary windings of which through diodes 15 and 16 are connected to resistors 17 and 18, connected in series with each other and the thyristor control circuit 1 and 2,

The device works as follows.

It is intended to supply the load 3 with current and voltage of different directions and polarities. The magnitude of the voltage on the load 3 is regulated in a phase manner by blocks 7 and 8,. signaling the opening to thyristors 1 and 2 through amplifiers 5 and 6; the phase of these signals is changed by setpoint 10, which is, for example, a constant controlled voltage source or a feedback regulator; groups 1 or 2 and one of blocks 7 or 8 due to the fact that

Simultaneously with the locking of the previously running block 7 or 8, 11 or 12 are formed, and a pulse signal of up to 200 microns is produced at its output.

20 1-5A, which is supplied on the negative polarity of the input of two-pole, 5 or 6, diodes. This signal, passing through the transformer 14, the diode 16, is fed as a negative to the control.

25 thyristor electrode. As is well known, in the field of fry currents all single-operation thyristors have the property of interrupting the anode current when a negative signal is applied

, Q Because of this, the previously conducting thyristor is quickly turned off. This is an circumstance and increases the reliability, for the guaranteed switching off of the previously performed Tiris excludes the short circuit mode.

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A kani possible with premature (due to logical switching of l) switching on another group. In addition, the delay for the inclusion of another group of thyristors, it can be reduced to a value of about 0.5 ms. This leads to a reduction in the pause and increases the speed of the converter, simplifies the device and increases reliability by reducing the requirements for the sensitivity of the current sensor.

Claims (1)

Formula invented A device for controlling the thyras of a reversing converter consisting of two opposite-parallel thyristor groups, contains a current sensor whose input is intended to be included in the load circuit and the code is connected to the switch input, an output control signal setter connected to the inputs switch 9 allows the passage of signals in only one channel. When changing the direction of the current, the switch 9 does not allow the passage of pulses to the thyristors of the other direction — while the load current 3 of the existing direction of current does not decrease below a predetermined level. Sensor 4 typically has a sensitivity in the order of 0.5–3% of the rated current. After the current drops below the indicated level, the switch 9. locks the block 7 or 8 of the current direction and with a delay unlocks the other block 8 or 7. Simultaneously with the blocking of the previously stale block 7 or 8, the formers 11 or 12 produce a pulse signal at their output up to 200 µs, 1-5A, which is supplied on the negative polarity of the input of two-pole amplifiers 5 or 6. This signal, a passage through the transformer 14, diode 16 is applied as a negative to the control electrode of the thyristors. As is well known, in the area of low currents all single-operation thyristors have the property of breaking the anode current when a negative signal is applied, Due to this, the previously switched off thyristor is quickly switched off. This circumstance and increases the reliability, because the guaranteed shutdown of the previously conducted thyristor eliminates the short circuit mode A kani possible with a premature (due to a logic switch) switching on another group. In addition, the delay for the inclusion of another group of thyristors, it can be reduced to a value of about 0.5 ms. This leads to a reduction in the dead time and increases the speed of the converter, simplifies the device and increases reliability by reducing the sensitivity requirements of the current sensor. Invention Formula A device for controlling thyristors of a reversing converter, consisting of two anti-parallel thyristor groups, containing a current sensor, the input of which is intended to be included in the load circuit, and the code connected to the switch input, the control signal setpoint, the output connected to the two inputs 313907324 blocks of pulse-phase control, reverse speed, it is equipped with the outputs of which are connected to the inputs of the two shapers of short impolarization polarity of two amplification pulses, and the amplifiers of pulses of pulses, which are amplified by two half-waves and equipped with the pulses are intended for the negative-polarity inputs, nor to the corresponding groups of tiris, with the outputs of the switch of chetov, anti-phase outputs switching switch-rezi chatel connected to the inputs of the blocking-short pulses are connected to blocks of pulse-phase control of negative polarity inputs None of the corresponding pulse amplifiers, in order to ensure the reliability of the ICs.