SiC MOSFET开关损耗模型

摘要

相比于硅(Si)功率器件,碳化硅(SiC)金属氧化物半导体场效应晶体管(MOSFET)具有耐高温、耐高压、低导通电阻、快速开关等优势,能够极大提升开关速度、减小损耗.传统封装所引入的寄生电感(特别是共源极寄生电感)及SiC MOSFET自身特性参数的非线性现象对于SiC器件的损耗有待进一步评估.针对上述问题提出一种SiC MOSFET的开关损耗模型,并采用热学方法进行了开关损耗的测试.实验结果验证了该模型的准确性,为SiC MOSFET的电路设计提供指导和帮助.%Compared with silicon (Si) power devices, silicon carbide (SiC) metal-oxide semiconductor field effect transistor (MOSFET) can bear higher temperature,higher voltage with lower conduction resistance and higher switching speed. The parasitic inductance (especially the common source inductance) introduced by conventional packaging and the nonlinear parameters, such as transconductance and parasitic capacitances of SiC MOSFET affect switching losses and should be carefully evaluated. An analytical switching loss model is proposed to give a better understanding of the switching transitions and a thermal measurement method is adopted to get the switching losses. Experimental results verify the accuracy of this model and the model can be used to guide the design and evaluation of SiC MOSFET in power electronics circuits.