A Equivalent Circuit for Rapid Reproduction of IGBT Transient Thermal Impedance Graph

The thermal characteristics of insulated gate bipolar transistor (IGBT) module is attracted much attention, since the production consistency and reliability are affected when IGBT works in high temperature environment. Transient thermal impedance is better than steady-state thermal resistance for thermal characterization of the IGBT due to the reason that the IGBT mostly operates in pulsed current mode rather than in DC mode or continuous current mode. In this paper, a simple equivalent circuit is proposed and built in MATLAB Simulink for rapid reproduction of IGBT transient thermal impedance graph given in production datasheets. The reproduced transient thermal impedance graph can help engineers to calculate the current limit of a semiconductor device for different pulse durations.