With the rapid growth of electric vehicles and hybrid electric vehicles, rigorous design targets in terms of cost, efficiency, and power density have been set for automotive power electronics. Novel power module and inverter technologies based on wide-bandgap semiconductors have been developed to meet these design targets. Compared with conventional cooling techniques, which are normally applied only on one side of the power module, a double-sided cooling approach enables higher power density and lower thermal resistance.
In this work, we develop a three-phase power module that is double-side cooled using dielectric fluid jet impingement. In each phase, four silicon carbide power semiconductors are bonded to copper busbars without electrical insulation layers. A finite element analysis (FEA) model is created for thermal and thermomechanical analysis. Based on the modeling results, we develop a design space to correlate input and output parameters to generate response surfaces. We then use a multi-objective genetic algorithm-based optimization method to minimize the maximum junction temperature and thermal stresses within the power module. The multiphysics co-optimization approach enables an efficient design process of power modules with greatly reduced computational cost, as compared to conventional processes that rely on exhaustive numerical simulations and iterations.