A Double-Sided Cooling 6.5kV SiC MOSFET Power Module With Insulation Enhancement Design

SiC devices have subversive potential in the voltage level system above 6.5kV because of its high blocking voltage characteristics. However, the existing packaging schemes limit the performance of these devices. This paper aims to explore the potential of SiC power devices in medium-and high-voltage power modules, which means higher power density and reliability of insulation. The proposed packaging method is based on a double-sided cooling structure, with polyimide coating to enhance the breakdown field strength to the high electric field region in this structure. A 6500V half-bridge SiC power module is fabricated and tested to verify this method's superiority. This paper proposes a PD testing process of MOSFET power module to accurately test the insulation strength of the actual module and the insulation upper limit of the module structure design. Benefiting from the optimized layout and application of PI film enable the module to switch 6 kV within tens of nanoseconds with slight ringing and voltage overshoot.