Control stage for gate-turn-off thyristor - has transformer stage controlled by transistor to actuate switching thyristor over secondary winding and capacitor

摘要

The potential free control of switching thyristors is provided by an isolated pulse converter. The switching thyristor (8) is controlled by a transformer (1) acting as a pulse converter for firing and resetting. The primary winding is supplied with a voltage by gating a transistor to trigger the thyristor over one secondary winding (4) and a capacitor (7). As soon as the switching transistor (5) is turned off, the capacitor discharges over a switching stage (6) and the second winding to allow the thyristor to turn off.