A 380VDC/20A Bidirectional Solid State Circuit Breaker Using a Single GaN Four Quadrant Switch

Conventional bidirectional solid state circuit breaker (SSCB) designs use two back-to-back connected semiconductor switches to conduct current and block voltage in either direction. This paper presents the design and experimental results of a 380VDC/20A bidirectional solid state circuit breaker using a single GaN four quadrant switch (FQS) recently developed by Transphorm. The 650V FQS (TP65F060WS) serves as the main static switch in the SSCB. The SSCB is tested in a capacitor discharge circuit to characterize its reaction time and current conduction in forward and reverse polarity. A double pulse test is conducted to confirm the turn off characteristics and observe its turn on reactions. The results indicate that this new FQS is an excellent choice for future SSCB designs with significant component count reduction.