Investigation on the performance of thyristors for pulsed power applications

In this paper, we investigated the di/dt capability and the turn-on action of conventional thyristors (including common thyristor and GTO) with the assist of a series-connected saturable inductor under short pulse conditions. Although the common thyristor is proven to be not adequate for pulse application, the GTO behaves excellently and it exhibits the potential of being operated in the case of much higher di/dt and pulse current than its rated values. Our tests have originally resulted in a maximum di/dt of 5.5 kA/μs for a 10-μS half-sine wave current pulse of 13 kA amplitude by using a GTO, whose rated RMS on-state current is 800 A and di/dt capability is 400 A/μS. The measurements show that turn-on losses and conduction losses are less than 1 Joule. Detailed results on the temporal behavior with respect to voltage drop are presented. PSpice simulation circuit of the GTO is also developed.