Enhanced and Uniform Thermal Management System Based on an Integrated Vapor Chamber and Air-Cooled Heat Sink for High-Power EV Chargers

The need for high-performance thermal management systems is increasing as the power densities of SiCbased converters in electric vehicle (EV) chargers tend to also increase. This study explores the integration of a vapor chamber into heat sink designs, utilizing the evaporation condensation cycle of a working fluid to enhance heat dissipation and reduce thermal resistance. A detailed comparison was conducted, supported by a 60 kW DC-DC converter reference design from Wolfspeed, evaluating a vapor chamber-based heat sink against a traditional air-cooled design under identical conditions of operation. The results indicate that the vapor chamber significantly lowers junction temperatures of the switching power devices, preventing localized overheating and achieving uniform temperature distribution across the heat sink. These improvements allow to optimize heat sink dimensions and to achieve greater cooling efficiency, enabling more compact system designs. The results demonstrate that vapor chamber technology provides a robust and scalable alternative to conventional cooling methods for high-power electronics applications such as EV chargers.