Active voltage control of SiC-SIT circuit breakers for overvoltage suppression

400V DC distribution systems have attracted much attention recently as the next generation power distribution systems for data centers. For the reliability of these networks, the development of high speed DC circuit breaker for overcurrent protection is essential. In existing research, semiconductor DC circuit breakers using silicon carbide static induction transistors (SiC-SITs) show to be a promising candidate as these high speed DC circuit breakers. In this case, the overvoltage generated across the drain-source terminals of the SiC-SIT device during the turn-off process is highly dependent on the applied turn-off gate-source voltage and the variation in characteristic of the devices. In this paper, the active voltage control method is proposed to suppress the overvoltage to a predetermined range even when variation in characteristic of the devices exists. The effectiveness of the proposed method is demonstrated by experiments.