Thermoelectrics for Cooling Power Electronics

To increase the efficiency and reduce emissions, the hybrid electric vehicle (HEV), fuel cell vehicle (FCV), and electric vehicle (EV) types were developed. All these vehicle types rely on power electronics (PEs) to function. Yet, the reliability and performance of PEs are directly related to the operating temperature. Therefore, cooling is considered an option to reduce the operating temperature.

An examination of multiple cooling methods including conventional cooling, direct and indirect cooling, and spray cooling shows that the use of thermoelectric (TE) modules has multiple justifications including reliability, thermal control, operation in harsh conditions, and the non-application of refrigerants. Nevertheless, the coefficient of performance (COP) of TE devices falls heavily with large ΔTs.

To meet the demands of cooling PEs with a large ΔT, layering TE modules must be performed. Although a minimum application of several layers can be performed, increasing the number of layers from the minimum demand results in an increased COP.