SU470044A1 - Device for generating control voltages for semiconductor devices - Google Patents

Description

The invention relates to the field of automating electrical power facilities and is intended for generating control voltages for semiconductor devices, such as power thyristors. Devices for generating control circuits for semiconductor devices are known, which include a successively connected capacitor, a load element, such as the primary winding of a pulse transformer, and a thyristor, the control electrode of which is connected to the collector of the transistor, and a command block. However, the known devices for generating equalizing voltages do not provide a relay phase shift of 180 ° control pulses relative to the reference voltage. The proposed device for generating control voltages differs from those known in that for expanding the functionality, an additional thyristor is connected parallel to the thyristor, the control electrode of which is connected to the collector of the additional transistor, the bases of these transistors are connected to two anti-phase sources, and through the diodes to the common point of the capacitor and thyristors, and the emitters of the transistors are connected to the outputs of the command block. A schematic of the device for generating control voltages for semiconductor devices is shown in the drawing. A device for generating control voltages for semiconductor devices comprises a command block 1 having two outputs 2 and 3 connected to the emitters of transistors 4 and 5, the collectors of which are connected to the control electrodes of thyristors 6 and 7, and the bases with two AC sources 8 and 9 interconnected in antiphase and through diodes 10 and 11 with the connection point of thyristors 6 and 7 with capacitor 12. The second plate of capacitor 12 is connected to a load emitter, for which, for example, primary volt from the pulse transformer or the thyristor control switch. The command block has four states in its outputs, according to which it has four states of the device for generating voltage. With large resistances between outputs 2 and 3 (the electronic keys shown are open) there are no pulses at the output, and the capacitor 12 is charged to the maximum value of the voltage of the sources 8 or 9.

With low resistance, let us say on step 2, (the key is closed) pulses are formed at the beginning of each negative half-wave of the current source 8.

This happens in the following way. In the negative half-wave of the current source 9, the capacitor 12 is charged through the diode 11. The nost source 8 enters the base of the transistor 4 and the cathode of the diode 10 is positively coupled, and they do not conduct any current.

The control transition of the transistor 5 and the transition of the anode of the diode 11 are locked into the positive half-wave of source 9. At the same time, a negative half-wave flows from the AC source 8 through the base-emitter transition of transistor 4 and output 2 of the command block 1. At the same time the thyristor 6 electrode, includes the latter, and the capacitor 12 is quickly discharged through the anode — the cathode of the thyristor 6 and the load element 13.

Further, the processes are repeated.

With a small resistance, output 3 and a large resistance output 2 of command block 1 will similarly generate output pulses, but already in each half-wave of negative voltage (9).

With small resistances at outputs 2 and 3 of command block 1, no pulses will be output, since the current from the AC sources 8 and 9 will flow through the low resistance of the base-emitter transitions of transistors 4 and 5 1 through the output terminals 2 and 3 of the command block one.

Subject invention

A device for generating control voltages for semiconductor devices, comprising a series-connected capacitor, a load element and a thyristor, the control electrode of which is connected to the collector of the transistor, and with the command unit that the expansion of functionality parallel to the specified thyristor includes an additional thyristor, the control electrode of which is connected to the collector of the additional transistor, the bases of these transistors are connected to two sources AC voltages that are out of phase and through diodes with a common point of a capacitor and thyristors, and the emitters of the transistors are connected to the outputs of the command block.

WY /.