Characterization and performance comparison of reverse blocking SiC and Si based switch

Abstract

In this paper a custom made Reverse Voltage Blocking 1200V SiC switch or “current switch” (1200V SiC MOSFET in series with a 1200V SiC JBS diode) is compared with various other combinations of Reverse Voltage Blocking switches (with 1200V Si-IGBT, SiC MOSFET and Si-PIN diodes and SiC JBS diodes). The devices are tested under Reverse Voltage Commutation, Switch Overlap (turn on at non-zero current but zero voltage) and Hard Switching conditions. Test circuits have been constructed and tested at different dc voltage levels with various combinations of devices. The custom made current switch results show remarkable reduction of loss owing to reduced leakage inductance of the package. A new form of switching characteristic has been noticed and presented in this paper. The main motivation of the paper is to make a fair judgment on device selection for current stiff based hard and soft switching topologies.