Highly thermal conductive graphene-based heatsink tailored for electric propulsion SiC-based inverter

Abstract

This study introduces an innovative multidisciplinary design approach for highly conductive and lightweight pin-fin-based heatsinks leveraging the advantages of graphene technology. The primary objective is to optimize the thermal management of silicon carbide (SiC) based inverters within electric vehicles (EVs). To closely emulate the real SiC power module, comprehensive analyses, including scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS), are performed on the module. A detailed fluid dynamics model utilizing a 3D-conjugate heat transfer (CHT) methodology is employed to evaluate the thermal behavior of SiC power switches in contact with the coolant. The multidisciplinary analysis is initially implemented on an aluminum-based heatsink, validated experimentally, and subsequently compared to graphene. The integration of graphene in the heatsink design demonstrates notable improvements, including a 24.4 % increase in the heat transfer coefficient (HTC) and a 19.6 % reduction in thermal resistance (sink to fluid) at a 6 l/min fluid flow rate compared to its aluminum counterpart. Consequently, the SiC chips within the graphene-based heatsink exhibit an 11.5 % lower temperature rise compared to the aluminum version. The improvements in the cooling solution for SiC inverters in EVs, achieved through the adoption of graphene instead of traditional metals, serve as a proof of concept. This signifies a step forward in prioritizing the crucial balance between performance and power density.