A Novel Three Phase LCL Dual Active Bridge Converter to Reduce RMS Phase Current

Three phase dual active bridge (3ph-DAB) is one of the promising isolated bidirectional dc-dc converter (IBDC) for high power industry application attracting more and more attention. However, the conventional single-phase shift (SPS) modulation brings obvious shortcomings such as high root-mean-square (RMS) current, massive circulating energy and soft-switching failure. Although many modulation schemes are proposed to solve these issues, most of them are very complex to be used. This paper proposes a novel three phase LCL dual active bridge (3ph-LCL-DAB) topology to reduce the high RMS phase current especially at heavy load situation with large voltage ratio. Adjusting values of phase inductor and capacitor, the RMS phase current is reduced significantly in the proposed 3ph-LCL-DAB converter with SPS control. Simulation and experiment results verify its effectiveness.