TVS Diode Coupled Gate Driver Circuit for Series Connected Power Devices used in Circuit Breaker Applications

Power semiconductor devices play an important role in circuit breakers (CB) to provide fast, arc-less, fault current interruption in dc distribution systems. Series connection of power devices is often used to increase the breaker voltage rating for application in medium voltage dc systems. This paper presents a low-cost gate driver circuit based on passive components which can achieve gate control of the series power device stack using only a single isolated gate driver IC. The circuit provides reliable coupling of the CB logic control signal while achieving a balanced device voltage distribution during the fault turn-off event. Transient voltage suppression (TVS) diodes are utilized to limit the turn-off voltage of the power devices and provide the current return path for the gate capacitor discharge of the upper device(s). Simulation and experimental results are provided to verify circuit operation in a dc solid state circuit breaker system.