A Novel Half-Full-Bridge Split-Capacitor DC-DC Converter Based On Dual-Active-Bridge Topology

Abstract

In this paper, a novel half-full-bridge DC-DC converter based on the split-capacitor dual-active-bridge (DAB) converter is proposed. In the proposed topology, the primary and the secondary sides of the transformer windings are connected to the midpoint of the input and the output split capacitors, respectively. Therefore, the switching voltage stress in the proposed converter is half of the conventional DAB converter. In addition, two power switches are omitted in the proposed converter compared to the conventional DAB converter, which consequently reduces the switching loss, increases the total efficiency, and makes the converter more affordable. Also, the proposed converter can easily connect to the multi-level inverter (MLI) for grid-connected applications, without adding the extra capacitors. To ensure the zero-voltage-switching (ZVS) for all the power switches at full load range under the single-phase-shift (SPS) modulation, the optimization method of the magnetizing inductor current is employed. Furthermore, the comparison is made between the proposed topology, conventional DAB converter, and the split-capacitor DAB (SCDAB) topology. The simulation results using MATLAB/Simulink verifies the performance of the proposed topology and the mentioned advantages.