A Novel Asymmetric Duty Modulation Control of Dual-Active-Bridge for LVDC Applications

Abstract

As a traditional dual-active-bridge (DAB) converter control strategy, phase-shift (PS) control has some defects, including the large root-mean-square (RMS)value of current stress when the voltageson both sides mismatch. Therefore, asymmetric duty modulation (ADM) control is introduced, which can effectively reduce the (RMS) current and improve the efficiency of DAB. However, the influence of the backflow power is seldom considered in the research of ADM control. Subsequently, in this paper, compared with the conventional ADM control, a novel ADM control scheme is proposed, where the backflow power grows down substantially. In the meanwhile, there exists tremendous RMS value of current stress in DAB when operating under EPS control. Aforementioned modified ADM control can retard the RMS value of current stress gradually. Finally, the effectiveness of the proposed control scheme is verified by simulation results.