Development of Dual Active Bridge DC-DC Converter to Achieve High Efficiency in Wide Voltage and Load Range and Application to V2H Systems

Abstract

This paper proposes a zero-voltage switching (ZVS) scheme for a dual active bridge (DAB) converter in the full load range. The switching state of the DAB converter with a phase-shift control becomes a hard switching state under an input and output voltage imbalance or light load. Thus, the proposed method regulates the phase-shift angle, output voltage angle of full-bridge circuits, and switching frequency to achieve ZVS for the DAB converter. The DAB converter implementing the proposed ZVS scheme is applied to vehicle-to-home (V2H) systems. Experimental results reveal that a V2H unit using the DAB converter achieves an efficiency 97.2% with the proposed ZVS scheme.