Circuit Simulation Method for Insulated-Gate Bipolar Transistor Short-Circuit Operation with High Accuracy

Abstract

In this paper, we propose a novel method to improve the circuit simulation accuracy of insulated-gate bipolar transistor (IGBT) power devices under a short-circuit state. To determine the IGBT junction temperature, the transient thermal resistance of an IGBT device on the order of micro seconds is estimated by transient thermal simulations. The saturation current without self-heating effects is estimated based on a short-circuit test and the transient thermal resistance. The IGBT SPICE parameter is extracted from the saturation current characteristics during the short-circuit state. The coupled electrical-thermal simulations with the SPICE model and thermal resistance model are applied to several short-circuit evaluations with different parasitic impedance and gate driving condition, and the results are consistent with the measured current and voltage waveforms.