碳化硅MOSFET的Matlab/Simulink建模及其温度特性评估

为了更好地评估碳化硅(Silicon carbide,SiC)MOSFET在功率变换装置中的性能,需要建立精确的SiC MOSFET模型。针对传统的SiC MOSFET的建模方法的不足,在Matlab/Simulink环境中提出了一种基于先进迁移率模型的SiC MOSFET模型。利用Matlab/Simulink强大的数学处理能力和丰富的模块功能,该模型考虑了实际SiC/SiO_2界面特性的影响。利用SiC MOSFET的产品手册中的实测曲线和所搭建的实验电路的测试结果验证了所建立模型的准确性。基于所建立的模型,研究了SiC/SiO_2非常重要的界面参数——界面陷阱电荷对SiC MOSFET温度特性的影响;从模型和实验上对比了SiC MOSFET与Si MOSFET在开关电路中瞬态温度的变化,结果显示碳化硅功率器件具有非常优秀的温度特性。

Matlab/Simulink Modeling and Temperature Characteristics Evaluation of SiC MOSFET

For the purpose of properly assessing the role of SiC MOSFET in the application of power converter, an accurate model of SiC MOSFET is necessary. In this paper, a SiC MOSFET model is proposed based on an advanced mobility model in Matlab/Simulink environment. For the powerful ability of solving equations and plenty of tool box in Matlab/Simulink, more complex physical effects can be incorporated into the model of SiC MOSFET. The accuracy of the model is validated with the production Datasheet and experimental results. Based on the developed model, the effect of SiC/SiO2 interface traps on the transient temperature of SiC MOSFET is discussed, and the comparison of temperature characteristics between SiC MOSFET and Si counterpart is carried out. Results show that SiC device exhibits very excellent temperature behaviors.