A Novel Gate Driver for Active Voltage Balancing in 1.7kV Series Connected SiC MOSFETs

This paper addresses active voltage balancing method for series connected 1.7 kV SiC MOSFETs. The series connection of 1.7 kV SiC MOSFETs have potential to replace medium voltage IGBTs (4.5 kV) due to their high switching speed and improved reliability. Series connection of SiC MOSFET is challenging due to possibility of voltage mismatch, voltage spike and device current spike in leg configuration. A novel gating technique has been introduced to reduce the voltage mismatch and voltage spike due to di/dt. Experimental results have been performed with series connection of two SiC MOSFETs and validated with theoretical calculations.