GaN-FET based dual active bridge DC-DC converter

Abstract

This paper describes a high step-down unregulated, fixed-ratio DC-DC converter (DCX) based on the dual active bridge (DAB) power stage operating at high switching frequency using enhancement-mode Gallium-Nitride-on-Silicon (GaN) transistors. The DAB power stage design as well as a comparison of losses using GaN and silicon MOS devices is based on a detailed state-plane analysis of resonant transitions. Experimental results are presented for a 150 W, 150-to-12 V prototype DCX operating at 1 MHz switching frequency.