Passive Resonant Level Shifter for Suppression of Crosstalk Effect and Reduction of Body-Diode Loss in SiC-Based Bridge Leg

A passive level shifter that can suppress the effect of the unavoidable crosstalk phenomenon in bridge-leg configuration and produce low off-state gate-source voltage to result in low body-diode forward voltage of SiC MOSFETs will be presented. Its structure consists of two main parts. The first one is a passive level shifter that can give a static negative gate-source voltage upon turning off the SiC MOSFET. The second one is a resonant tank that can produce voltage pulses to lower the spurious triggering pulses to a level below the gate-source threshold voltage, thereby avoiding spurious triggering. The proposed level shifter is simple and does not require any extra voltage source and switching network. Its performance has been evaluated on a 1kW SiC-based H-bridge inverter. Experimental results show that the total loss of the inverter can be reduced by 16.43% with the level shifter.