Analysis, Design, and Experimental Results for a High-Frequency ZVZCS Galvanically Isolated PSFB DC-DC Converter over a Wide Operating Range Using GaN-HEMT

This paper investigates the potential of emerging gallium nitride (GaN) high-electron mobility transistors (HEMT) power devices to meet certain conversion challenges. The advantages utilizing GaN HEMT in a high-frequency, high-power isolated DC-DC topology are explored experimentally. Using HEMT’s parasitic elements, e.g., output capacitance, and leakage inductance transformer, soft switching zero-voltage zero-current (ZVZCS) phase shift converter is proposed. Accordingly, freewheeling current terminated, realized for most primary secondary active devices. Furthermore, without using any additional circuitry, overshoot voltage across bridges rectifier diodes clamped at their level. In addition, high-frequency transformer optimized minimize overall losses (e.g., winding core losses). Combined conductor types, litz wire copper foil, shows good electrical thermal performance by reducing AC DC resistance. Finally, 5 kW, 100–250 kHz prototype built tested. experimental results show efficiency up 98.18% whole converter.