Thermal Performance Optimization of Pin-Fin Structures in Electric Vehicle Power Modules via Response Surface Methodology

Integrated Pin-Fin heatsinks have emerged as a promising thermal management solution for automotive-grade power modules by effectively reducing junction-to-fluid thermal resistance. However, conventional parametric design approaches exhibit critical limitations in quantitatively characterizing Pin-Fin morphology, resulting in constrained design freedom and suboptimal thermal-fluidic performance coordination. Systematic investigations into optimizing both thermal resistance and hydraulic pressure drop minimization within constrained design spaces remain underexplored, presenting an urgent need for innovative thermal-fluidic co-design methodologies. This technological gap critically impacts the development of next-generation high-density power modules requiring enhanced cooling efficiency under stringent packaging constraints. This paper presents a systematic methodology combining response surface optimization and topology optimization to address these challenges. A mathematical framework is established for comprehensive description of integrated Pin-Fin morphology and array configuration, accompanied by theoretical modeling of thermal-fluidic characteristics. The proposed multi-objective optimization model enables concurrent optimization of heat dissipation efficiency and flow resistance characteristics. Experimental validation was conducted through a nondestructive aging test platform, with comparative analyses against commercial automotive power modules under both fixed operating conditions and actual vehicle driving cycles. The optimized Pin-Fin design demonstrates a 7.62% reduction in junction-to-fluid thermal resistance and eliminates 80% of multi-chip junction temperature variations. This research provides a novel paradigm for developing low thermal resistance integrated Pin-Fin heatsinks in high-power automotive applications, significantly advancing thermal management capabilities for next-generation power electronic systems.