SU1732456A1 - Device for turn-off of power thyristor - Google Patents

Abstract

The invention relates to a pulse technique and can be used in devices that switch electric 2 + & equipment in cars. The purpose of the invention is to increase the speed and reliability of operation. The device for switching off the power thyristor 3 comprises a switching thyristor 1, the first and second capacitors 6 and 7, the resistor 8, the control unit 9. The introduction of the semiconductor key element 10, which is connected in accordance with the thyristor 1 between its output terminal and the connection point of capacitors 6, 7. and connecting the control input of element 10 to the auxiliary output of block 9, reduces the discharge time of the capacitor 7. limit the reverse voltage on it and exclude the possibility of failure while simultaneously unlocking the thyristors 1 3. 1 or with CO with /

Description

The invention relates to a pulse technique and can be used in devices that switch electrical circuits in automobiles.

The aim of the invention is to increase the speed and reliability of operation by reducing the discharge time of the second capacitor and by limiting the reverse voltage capacitors and eliminating the possibility of loss of controllability while simultaneously unlocking both thyristors.

The diagram shows the circuit diagram of the device for switching off the power thyristor.

The device for switching off the power thyristor contains switching thyristor 1, the first output of which is connected to the first supply bus 2 and the same output output of the power thyristor 3, the second output of which through the load 4 is connected to the second supply bus 5. first 6 and second 7 polar capacitors connected in series between the second output terminals of the same power 3 and commuting 1 thyristors. a resistor connected between the connection point of the unipolar outputs of the first 6 and second 7 capacitors and the second supply bus 5, control unit 9, the outputs of which are connected to the inputs of the power 3 and switching 1 thyristors semi-conductor key element 10, which is connected according to the switching thyristor 1 between its the second output terminal and the connection point of the first 6 and second 7 capacitors, and a diode 11, which is connected in opposite to the power thyristor 3 between its second output terminal and the connection point of the first 6 and second 7 end capacitors, while the control input of the semiconductor key element 10 is connected to the auxiliary output of the control unit 9.

As a key semiconductor element 10, for example, a transistor may be used (in necessary cases a limiting resistor may be connected in series with the transistor). The control unit 9 can be connected directly to the supply buses 2 and 5 and to the connection point of the capacitors b and 7 as well as to the cathodes of the thyristors 1 and 3.

The device for turning off the power thyristor works as follows.

The initial state — the thyristors are turned off, the capacitors are discharged.

When a triggering impulse is supplied to the input of the power thyristor 3 from the control unit 9, the thyristor 3 is turned on and connects the load 4 to the supply lines 2 and 5. At the same time, the capacitor 6 is charged through the resistor 8 to the source voltage

nutrition

When a triggering impulse is applied to the control input of the switching thyristor 1, it turns on and connects a chain of series-connected capacitors 6 and 7 to the first supply bus 2.

Due to the fact that one of the capacitors (capacitor 6) is charged in the same direction as the power source, and the voltage drop on the other (capacitor 7) is zero at the initial time, the voltage across the load doubles to the power thyristor 3, a reverse polarity voltage is applied, with the result that the flow of direct current through it

0 is stopped and it is turned off, while the capacitor 7 is charged and the capacitor b is discharged along the circuit: supply bus 2, switching thyristor 1, capacitors 6 and 7, load 4 and supply bus 5. Dose 5 of the capacitor 7 (if its capacity is exceeds the capacitance of the capacitor 6) can occur through the diode 11 and the load 4. After charging the switching capacitor 7, the current flowing through the switching thyristor 1 is reduced to a value less than the holding current, and it turns off, then to the control terminal of the key element 10 served unlocking impulse (signal), key element 10

Claims (1)

5 is turned on and the capacitor 7 is discharged, the circuit returns to its original state, in which it does not consume electrical energy. The inclusion of the key element 10 can occur simultaneously with the inclusion of the power thyristor 3. In the future, the circuit works in a similar way. The invention The device for turning off the power thyristor, containing a switching thyristor, the first output of which is connected to the first supply bus and the same output output of the power thyristor, the second output of which through the load is connected to the second supply bus, the first and second polar capacitors connected in series between the second like output terminals of the power and switching thyristors, a resistor connected between the point of connection of the single pin terminals of the first and second a capacitor and a second supply rail, a control unit which outputs are connected to inputs of the power and switching thyristors, characterized in that in order to enhance fast! interconnection and reliability of operation, introduced by the opposite to the power thyristor between its semiconductor key element, the co-second output terminal and the connection point is included according to the switching of the first and second capacitors, the thyristor between its second output terminal and the connection point of the first semiconductor and the second key element is connected to an expensive capacitor, and a diode, which is connected to the output of the control unit.