An Analytical Approach for Evaluating Turn-On Switching Losses in SiC MOSFET With Kelvin Pin: Concept and Implementation

With the progressive adoption of silicon carbide (SiC) power devices in modern power converters, exploiting their superior efficiency, faster switching speed, and higher power density, an understanding of the factors influencing these properties becomes vital. One such critical factor is switching losses, which can drastically affect overall system performance. This study develops and presents a new analytical model for predicting the turn-on switching losses in SiC MOSFETs with Kelvin pin. The proposed model, derived from a carefully constructed set of nonlinear differential equations, accounts for the nonlinearity of the transconductance by incorporating a novel transfer characteristic model. The model also incorporates the nonlinear junction capacitances effects. The developed analytical model allows for the prediction and optimization of turn-on switching losses in SiC MOSFETs, thus enabling improved energy efficiency and reliability. The accuracy of the proposed model is verified through comparison with experimental results obtained using the double pulse test board that was designed and constructed, demonstrating its applicability for the investigation of SiC MOSFET power losses.