Low-loss, Fast-acting Solid State AC/DC Breaker

Abstract:
Thyristors achieve lower conduction losses compared to IGBTs at the same current density. IGBTs, however, offer a much higher maximum turn-off current density compared to GTOs at operational voltage. We have previously demonstrated Silicon Power’s 6kV Super-GTO (SGTO) turn-off capability of 2kAcm^-2 when switched at 700V. We now present a hybrid circuit topology realizing the on-state efficiency of thyristors and the maximum controllable current of IGBTs; minimizing the size and weight of conventional cooling systems and snubber circuits. This topology enables up to an order of magnitude improvement in conduction loss and system size, proving advantageous in applications where steady state losses represent the highest power dissipation, like AC/DC breakers, fault current limiters and static transfer switches; saving kWs of power dissipation under normal operating conditions.