Comparison of the heat transfer capabilities of conventional single- and two-phase cooling systems for electric vehicle IGBT power module

This paper presents a comparison of conventional single-phase water/glycol liquid and innovative two-phase cooling technology for thermal management of high power electronics automotive IGBT modules during full drive cycle. The proposed two-phase cooling system is built using conventional automotive air conditioning components (condenser, expansion valve, compressor, and vapor and liquid lines) and conventional cold plate as used for single-phase cooling, thus the design does not require the development of new technology for its implementation. 3-D numerical simulation in COMSOL and experimental results of two-phase cooling have been obtained on a prototype and compared to conventional water/glycol cooling high power electronics modules, with considerable improvement on working temperature, power transfer capacity and equalization of die temperatures during a full driving cycle. These results suggest that two-phase cooling using the same cold plates as in single-phase cooling can be used to substantially improve the performance and reliability, of EV power converters without major changes.