Accurate IGBT Circuit Model Considering Impact of Dynamic Avalanche Phenomenon

Abstract:
We propose a novel circuit simulation model of IGBT to analyze the influence of the dynamic avalanche. One features of the proposed model is that the current source derived from the Poisson equation is installed into the conventional IGBT circuit model to simulate the avalanche current under real circuit operating conditions. Turn-off behavior of four parallel connected IGBTs is simulated, and the proposed model reproduces the current concentration caused by the dynamic avalanche accurately. The optimal driving condition of IGBTs can be designed by using the proposed model for various circuit and device parameters.