Modular Heatsink Design for High Power Converters Considering Cooling Wind Speed Optimization

Nowadays, with modern society's increasing demand for power conversion, there are increasing demands towards high power converters. Cascaded structure is frequently used to build high power converters. For example, MMC is adopted in flexible HVDC [1] and series connected SiC MOSFETs are used in DC/DC converters [2]. Among these applications, the common point is that cascaded structure raises working voltage, meanwhile the requirements for insulation are improved. In these applications, traditional integrated heatsink structure is not applicable any more, therefore this paper proposes a modular heatsink design, which reduces the insulation stress a lot. Besides, the analytical model between wind speed and heat dissipation effect is established which shows the heat dissipation effect does not increase linearly with wind speed, hence a trade-off design principle is proposed. Finally, the simulation and experimental results verify the validity of proposed methods and the accuracy of analysis.