A Temperature-Dependent Physical Thermal Network Model Including Thermal Boundary Conditions for SiC MOSFET Module

Abstract

SiC MOSFETs have received great attention due to their excellent electrothermal properties. Accurate junction temperature information of SiC MOSFETs ensures safe operation and helps effective thermal management. However, the existing thermal models have limits to correctly predict the thermal behaviors, whose parameter extraction processes are normally complicated. Most of the thermal models generally omit the temperature effects, which greatly impairs their usefulness and effectiveness. Here, a temperature-dependent physical resistor–capacitor ( <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">RC</i> ) network model is proposed, which can accurately characterize the thermal behavior of SiC MOSFETs particularly under high-temperature conditions. Meanwhile, the boundary conditions are fully investigated and modeled, which guarantees the adaptation of the proposed model for different real-field applications. The proposed method can remarkably simplify the process of parameter extraction since only the steady-state temperature distribution information is required with the assistance of finite-element method (FEM). Finally, the effectiveness and the robustness of the proposed model are validated by FEM simulation and experiments.