Transient modelling of an ev inverter heat sink with pcm

Abstract

One of the problems with cooling an IGBT inverter chip is that its heat generation is not constant. These chips tend to produce heat in pulses which results in high peak chip temperatures. Transient modelling is required to determine the suitability of a heat sink and to ensure the max peak temperature is not exceeded. This paper demonstrates a method of transient thermal analysis using a thermal resistance/capacitor network. A sample heat sink was modelled and then experimentally tested to validate the model. A novel method of modelling phase change materials (PCM) using the thermal resistance/capacitor network was also demonstrated. The use of PCM was modelled because it has the potential to reduce peak chip temperatures. This model was used to optimise the PCM location, melting temperature and mass.