Multi-Physics Modeling of Power Electronic Converters with Liquid Immersion Cooling

Power electronics and electric motor-drive systems have been increasingly utilized in various emerging industry applications, such as electric vehicles, electric aircraft, data centers, and energy storage systems. However, conventional thermal management technologies such as heat sink and indirect liquid cooling for power electronics and motor drives face increasing challenges in further improving the systematic reliability, power density, and energy efficiency. Thus, developing advanced cooling technologies will be of paramount importance to boost the performance of power converters. In this paper, multi-physics modeling and performance characterization of a 50-kW Silicon Carbide (SiC) T-Type power converter equipped with immersion cooling is presented. First, the electrical performance of the converter is investigated, and semiconductor losses of the converter are calculated which serve as the heat sources for the subsequent thermal simulation. Afterwards, the thermal behavior of the liquid-immersed converter is simulated and compared with the conventional heat sink design considering different operating conditions. By conducting computational fluid dynamics (CFD) simulations in Ansys Fluent, the enhanced heat flow dissipation of oil immersion cooling for the T-Type power converter is demonstrated.