Comparative study of a 100kW PV WBG inverter using 1200V SiC MOSFET and JFET cascode devices

摘要

This paper compares the efficiency and power density of a 100kW five-level T-type inverter based on the type of SiC device used to implement it: Wolfspeed SiC MOSFET T-Type modules, Wolfspeed Gen-3 discrete SiC MOSFETs, and USCi discrete SiC JFET cascode devices. Analytical results indicate that the JFET cascodes experience the least overall power loss, though the discrete MOSFETs experience the least switching loss. In addition, an optimized pin-fin heatsink system has been designed to compare the power density of this inverter using these devices. It shows that the discrete devices can use 72% of the heatsink weight that the MOSFET modules require. A 100kW inverter using SiC T-type modules has been built, and downscaled experimental results are provided to verify the analysis.