采用降温曲线的SiC MOSFET模块热参数的测量

Measurement of Thermal Parameters of SiC MOSFET Modules With Cooling Curves

SiC作为新一代宽禁带半导体材料,凭借其优异的电热特性,正逐渐投入市场并取代Si器件,然而其在实际应用时仍然面临着由于热应力带来的可靠性问题。为此,该文提出利用SiC MOSFET模块中的反并联SiC SBD芯片的正向导通压降来获取其降温曲线,并根据降温曲线的拟合时间常数与模块热网络参数之间的关系,求解得到模块的RC Cauer热网络参数。该方法在简化功率测量的步骤与热稳态平衡的条件的同时,还可得到精确的热网络模型用于各方面研究。

SiC,as the new wide bandgap device,is gradually taking the place of Si device in the industry for its excellent electro-thermal properties.Nevertheless,the reliability problems caused by the thermal stress are still concerned in the application.This paper proposed the method to acquire the junction temperature cooling curves of antiparallel SiC SBD in the SiC MOSFET module by its forward voltage,and then obtained the RC Cauer thermal network parameters from the relation between time constants from fitting the cooling curves and Cauer thermal network parameters of the module.The method not only simplify the power loss measurement and thermal-equilibrium condition,but also get the thermal network parameters for more research.