A Comparative Study of Thermal Management Strategies for Overcurrent in Aircraft Power Electronics Applications

The increasing power density in more electric aircraft (MEA) systems poses significant thermal challenges for power electronics, especially during overcurrent scenarios and fault conditions throughout flight cycles. Efficient thermal management is therefore essential. This article presents a comparative study of three thermal management strategies—liquid metal phase change material (PCM), thermoelectric cooling (TEC), and heat pipes—evaluated in terms of time-scale response and thermal performance under overcurrent conditions. Results indicate that liquid metal PCM responds in the seconds range, while TEC and heat pipes provide faster responses in the millisecond range. All three strategies demonstrated significant improvements over conventional power module designs, achieving thermal resistance reductions of 45%, 35%, and 21% for heat pipe, TEC, and PCM, respectively. The heat pipe configuration exhibited the lowest thermal resistance and the most substantial reduction in junction temperature during overcurrent conditions. The overcurrent cycling test demonstrates that all three strategies effectively reduce both the mean junction temperature and junction temperature swing, resulting in an increased number of cycles to failure.