An Energy based Approach to Calculate Actual Switching Loss for SiC MOSFET from Experimental Measurement

It is well known for SiC MOSFET that the integration of the product of experimentally measured drain current and drain-source voltage results in inaccurate estimation of switching loss. This paper presents an alternative energy based approach to accurately compute switching loss from experimentally measured waveforms. This indirect but relatively simple method requires device parameters available in data-sheet. It is derived from the behavioural model through approximations. Detailed non-linear capacitance model of the SiC MOSFET is used that results in accurate estimation of actual turn on and turn off losses. It has been verified through behavioural simulation and experiment for a SiC MOSFET and schottky barrier diode (SBD) pair for a wide range of operating conditions.