Gate units for GTOs
The gate unit is designed to trigger large gate-turn-off-thyristors (GTOs) for traction and static applications. It controls GTOs with turn-off currents up to 4000 A and off-state voltages up to 4500 V.
The gate unit supplies the turn-on pulse, the temperature dependent controlled continuous gate current to keep the thyristor conductive, the turn-off pulse and the negative continuous gate voltage for keeping the GTO in permanently blocked condition.
Optical fibers are used to send the command signal to the gate driver and to transmit the status feedback.
An integrated transformer electrically isolates the supply from the output (high-voltage).