Design Considerations of High-Voltage-Insulated Gate Drive Power Supply for 10 kV SiC MOSFET in Medium-Voltage Application

The performance of the gate drive power supply (GDPS) greatly impacts the safety and reliability of the gate drive for power semiconductor power devices. This paper focuses on the design of isolated gate driver power supply for 10 kV silicon-carbide (SiC) MOSFET for medium-voltage (MV) applications. Different insulation schemes are compared for the high-voltage insulated transformer in GDPS. Impact factors for transformer interwinding capacitance are analyzed, with which, a low inter-winding capacitance design approach is proposed for the high-voltage insulated transformer. Furthermore, an upward-voltage-reference based voltage regulation scheme is proposed for achieving good load regulation without output voltage feedback. Finally, a 20-kV-insulated GDPS is built and tested, and experimental results are presented to verify the effectiveness of the design approach.