A LCL-type DAB converter with hybrid modulation strategy

This paper presents the operation, analysis, design, and experimental results of a dual-transformer LCL-type dual active bridge converter with a hybrid modulation strategy. The proposed modulation strategy can effectively achieve full-range zero-voltage switching (ZVS) operation and eliminate backflow power on both the primary and secondary sides when operating in heavy load range. In comparison to the previous modulation strategies, the proposed strategy demonstrates lower root-mean-square (RMS) currents at equivalent power levels. The theoretical analysis is validated through simulation and experimental test on a 400W lab prototype.