Multiphysics Analysis of Heat Sink Designs for Efficient Thermal Performance in Power Electronics Systems

The thermal management capability of power electronic (PE) systems has a critical impact on the performance and efficiency of electric, fuel cell, or hybrid vehicles. Bus bars, high resistance sensor devices, semiconductor switches, power capacitors are the primary components, which has major contribution in total heat generation in electrical drive unit. As PE packaging sizes are projected to become smaller, the challenge of managing increased heat dissipation becomes more critical. Hence, this paper numerically compares conventional and advanced cooling strategies to determine the best possible thermal management scenario. A multi-physics finite element model, integrating fluid, electrical, thermal, and structural fields, is employed to analyze heat generation within the PE system and the associated cooling mechanisms. Due to the significant impact of surface roughness and topology on electrical and thermal contact resistance, the Cooper-Mikic-Yovanovich (CMY) correlation is utilized to simulate the contact losses between busbar connections. The research enhances comprehension of optimized cooling techniques, demonstrating superior performance over conventional methods. Additionally, it validates an effective numerical procedure for analyzing PE cooling phenomena.