Numerical simulation of the junction temperature, the coolant flow rate and the reliability of an IGBT module

By increasing coolant flow rate, the junction temperature of IGBT power modules can be reduced but this is accompanied by undesirable increase in pressure and pumping power. In this paper, numerical simulation and multi-objective optimization methods have been used to obtain a trade-off relationship between reducing IGBT junction temperature and the increase in pressure drop due to increased coolant flow-rate. It is found that the pressure drop increases more than 100% for a 10% reduction in IGBT maximum junction temperature due to the increased coolant flow rate. The impact of the IGBT junction temperature on the power module lifetime has also been investigated. Moreover, an effective and efficient work-flow in integrating numerical methods software results for performing thermo-mechanical analysis under power cycling conditions has been explored