Transient DC-Bias and Hard-Switching Mitigation for Fast Power Reversal in Dual-Active-Bridge DC-DC Converters

Abstract

As one of promising power interfaces in Microgrids, dual active bridge (DAB) converters have been extensively studied and widely applied. However, dc-bias current during its transient process, as well as the electromagnetic interference and the reduced efficiency caused by the hard-switching operation, urgently need to be addressed. In addition, traditional transient optimization strategies mainly focus on unidirectional power transmission, which cannot ensure fast power reverse operation of DAB converters and eliminate dc-bias current and hard-switching defects at the same time. To address this issue, a novel transient power reversal control (TPRC) strategy based on the principle of straightforward phase-shift optimization is proposed in this article. Extensive and comparative experimental evaluations under various scenarios have been conducted to verify the effectiveness of the proposed TPRC strategy.