A new compact high dI/dt gate drive unit for 6-inch GCTs [gate commutated turn-off thyristor]

A gate driver applying a ring of ceramic chip capacitors and MOSFETs around a GCT is presented, achieving unprecedented circular homogeneity of gate turn-off current and gate dI/dt-capability (>35kA//spl mu/s). A fast charger is added to reset the capacitor's voltage within less than 150 /spl mu/s after every GCT turn-off process. The turn-off current capability of 6 kV 6-inch asymmetric GCTs and 6 kV 6-inch reverse conducting GCTs is investigated with the new gate driver and compared to that achieved under traditional gate drive. Turnoff current capability improvement by x is observed with the new gate driver, wherein 18%