SiC Power Devices for Applications in Hybrid and Electric Vehicles

Power electronic inverters and converters are an essential technology in the battery management and propulsion for Hybrid and Electric vehicles (HEVs). In order to improve competitiveness of HEVs there is a drive to improve the conversion efficiency of the power electronics. Using Silicon Carbide (SiC) power devices has been identified as a key enabler of future improvements in performance but it is essential to understand how these devices perform in an automotive context. Two similar half bridge circuits has been built using SiC MOSFETs, one with and the other without anti-parallel Schottky SiC diode. In this paper the power loss and efficiency of half-bridge has been compared as the dead-time is changed. Effect of changing dead-time on the converter are shown. The paper gives insight into these phenomena with additional experimental data supported by simulation. The implications for using SiC devices in both DC to DC and DC to AC converters are discussed.