Non-Magnetic Resonant-Type High-Frequency High-Voltage Power Conversion with Silicon Carbide Power Semiconductor Devices

A novel non-magnetic resonant-type high-frequency (HF) high-voltage (HV) power conversion with coreless planar multi-layer printed circuit board (PCB) winding transformer is proposed to achieve high efficiency, planar packaging structure, compact size advantages and compatible with high magnetic field environment. 1.2kV SiC MOSFETs are introduced in the HF power inverter and 1.2kV SiC Schottky diodes are introduced in the HV multiplier. The switching characteristics of HV SiC MOSFET are characterized for HF switching. A parallel-connected SiC-MOSFETs layout is proposed to achieve smaller stray inductance, current-sharing and thermal balance. The comprehensive design consideration on the SiC MOSFET gate driver circuit is given and improved in consideration of the short-circuit protection and higher dv/dt immunity. The SiC MOSFET gate driver circuit prototype is successfully tested at 300-500kHz. The experimental results show that non-magnetic HF HV power conversion prototype with 310W output power and 1kV output voltage can achieve 80.5% efficiency and 1.09kW/L power density, thus validate the design effectiveness.