100 A Solid State Circuit Breaker Using Monolithic GaN Bidirectional Switch with Two-Step Gate-Discharging Technique

We demonstrate a solid state circuit breaker (SSCB) using monolithic GaN bidirectional switch with two-step gate-discharging technique. A GaN bidirectional switch with dual-gate structure based on gate injection transistor (GIT) is employed to reduce on-state resistance instead of series-connected transistors which are commonly used. Furthermore, a two-step gate-discharging technique which prevents both short-circuit current and surge voltage from increasing during turn-off transient is proposed. The fabricated SSCB exhibits interruption for short-circuit current of 100 A under DC bus voltage of 380 V within 0.9 μs with no surge voltage. These results are attractive for DC circuit breakers in various application fields such as DC power distribution systems.