Low Interwinding Capacitance Design for PCB-Winding Based Transformer in Self-Powered Gate Drive Power Supply for High-Voltage SiC MOSFET

High-performance gate drive power supply (GDPS) is the critical component to guarantee the reliable and safe operation of the gate driver for SiC semiconductor power devices. To meet the demand for suppressing the common-mode interference (CMI) resulting from the high dv/dt, it is of significance to design GDPSs with low interwinding capacitance. In this paper, design considerations, including winding layout design and transformer geometric design, are proposed as a guidance for designing the printed-circuit-board-winding (PCB-winding) based transformer in the GDPS. The doing so results in an optimized transformer design with ultra-low interwinding capacitance of 0.86pF. Finally, a prototype is fabricated in the lab to verify the feasibility of the proposed work.