公开(公告)号：US11018666B1

公开(公告)日：2021-05-25

申请号：US16795988

申请日：2020-02-20

Applicant: ABB Schweiz AG

Inventor： Yu Du ,  Xiaoquing Song ,  Yuzhi Zhang ,  Adil Oudrhiri

IPC: H03K17/04 ,  H03K17/13 ,  H03K17/60

Abstract: An apparatus and method that can accelerate the turn off time for a thyristor current interrupter. Following commutation of a load current from a main thyristor to an auxiliary turn-off unit, a capacitor of the auxiliary turn-off unit can provide a resonant current to create a zero current crossing for turning the main thyristor off, as well as provide a reverse bias voltage for the main thyristor. The auxiliary turn-off unit can hold the main thyristor off and facilitate sufficient time being available for main thyristor to block forward system voltage. A voltage level of another capacitor of the auxiliary turn-off unit can, with a switch of the auxiliary turn-off unit and the main thyristor turned off, be increased to a level that triggers at least one voltage-clamping unit to absorb electrical power from that capacitor. The load current passing in the auxiliary turn-off unit can be decreased as the electrical power is absorbed to a level at which one or more auxiliary thyristor switches of the auxiliary turn-off unit can be turned off.