  In a hard switched MOSFET based converter, turn-on energy losses is
predominant in the total switching loss. At higher junction temperature the
turn-on energy loss further increases due to the reverse recovery effect of the
complementary MOSFETs body diode in a half-bridge configuration. Estimation of
the switching loss under different operating conditions at an early design
stage is essential for optimising the thermal design. Analytical switching loss
models available in literature are generally used for estimating the switching
losses, due to its accuracy and simplicity. In this paper, the inaccuracy in
the reported loss models due to non inclusion of temperature dependent reverse
recovery characteristics of body diode, is investigated. A structured method to
determine the temperature-dependent switching loss of a SiC MOSFET in a
half-bridge is presented. A simple methodology has been proposed to analyze the
carrier lifetime's temperature dependencies of a SiC MOSFETs body diode. Device
parameters from a 1.2kV/36A SiC MOSFETs datasheet are used for developing the
loss model and experimental validation of the model.
