Method and apparatus for controlling reverse-conducting GTO thyristor.

摘要

A reverse-conducting GTO thyristor comprises a gate turn-off thyristor and a diode which are formed on a single semi-conductor substrate so as to have a common layer and be connected electrically in an inverse-parallel connection. A power converter is composed of a plurality of pairs (21,22;23,24;25,26) of these reverse-conducting GTO thyristors connected in series, each pair ofthyristors being controlled so that they are turned on and off in opposite phases. An OFF gate pulse for one of each pair of thyristors continues from a time on or after the generation of an ON gate pulse for the other thyristor to the time when a recovery current flowing through the diode portion of the first thyristor is extinguished. The thus-extended OFF gate pulse functions to prevent any displacement current flowing through the GTO portion of the first thyristor during the recovery time for the diode portion thereof.