The existing power semiconductor device model based on ambipolar diffusion equation(ADE) can only describe the carrier distribution of quasi-neutral region precisely
leading to a limited accuracy when it is applied to modeling of high-voltage power device. In this study
a drift-diffusion model(DDM) based modeling approach with improved accuracy is proposed and applied to the integrated gate commutated thyristor(IGCT) circuit model.By characterizing the IGCT
the analyses reveal that there are the different orders of solving variables
and the characteristic parameters determined by high doping concentrations are the main factors.Moreover
the model stability and execution speed are improved by analytically modeling the highly doped region
by simplifying the boundary conditions of base region calculation
and by using a moving mesh method to solve the DDM equations. Finally
the simulation and experimental results of double-pulse test of IGCT show that
with high simulation speed comparable with ADE-based model
the proposed circuit model is superior to the existing models in its characteristic modeling at turn-off oscillation and punch-through stages.