Design of a Two-Switch Flyback Power Supply Using 1.7 kV SiC Devices for Ultra-Wide Input-Voltage Range Applications

摘要

This paper presents the design and evaluation of atwo-switch flyback power supply with ultra-wide input voltagerange (230–1300 V), fed from the floating dc bus of powerelectronics building blocks (PEBB) in medium voltage (MV)modular multilevel converter (MMC) applications. Rated at 80W, 48 V output, and operating at 50 kHz, the proposed converteruses 1.7 kV SiC devices and a planar PCB-winding transformerto achieve a low-profile form factor. Further, a pre-charge circuitand start-up sequence are developed as well, enabling the twoswitchflyback converter to wake up at 230 V. Experimentalresults are presented for verification and evaluation purposes.