A SiC IGBT Behavioral Model with High Accuracy and Fast Convergence

Abstract

In order to study the mechanisms of SiC IGBT, optimize the SiC IGBT based power conversion system and predict the electro-thermal performance of the circuits, a simple, high-speed and accurate behavioral model of SiC IGBT is proposed. In this model, three controlled current sources are used to simulate the voltage and displacement current of the three parasitic capacitors of SiC IGBT. The other two controlled current sources are used to simulate the I-V characteristics and tail current characteristics of SiC IGBT respectively. In the model, the interpolation method instead of the conventional polynomial fitting method is adopted, which could simulate the static I-V characteristics and C-V characteristics more accurately. The method to extract the C-V curves by using dv/dt and displacement current is proposed, which could accurately simulate the punch-through effect of SiC IGBT under high voltage. The proposed model is more concise, more accurate and faster than the existing complex physical based mathematical model, which is suitable for system level circuit simulation based on SiC IGBT.