A Hybrid-bridge based Dual Active Bridge DC/DC Converter with Compact Structure

In this paper, a new hybrid-bridge based active bridge (DAB) converter is proposed for interfacing the low-voltage and medium voltage in the DC grids. The proposed converter is composed of a two-level full-bridge and a three-level half-bridge circuit, which only has eight power switches in total. Comparing with the conventional hybrid-bridge based DAB converter with diode-clamped TL bridge, the proposed converter reduces the main device count by removing the clamping diodes. Thus, the proposed converter has a more compact circuit structure and a lower cost. Besides, the proposed converter can achieve the zero-voltages-witching (ZVS) for both primary-side and secondary-side power switches. The basic operation principle, characteristics, and performances of the proposed converter are analyzed in detail. Finally, the simulation results are provided to verify the proposed converter.