A Novel Bidirectional Modified Zeta Converter With Wide Voltage Conversion Ratio

Abstract

High-gain, nonisolated bidirectional dc–dc converters (BDCs) play a vital role in interfacing energy storage systems with microgrids and electric vehicles (EVs). However, the existing converters often operate within a limited duty cycle range and involve high component counts and significant voltage stress for achieving desired voltage gain. This article presents a novel noncoupled high-gain BDC that efficiently operates in the boost mode for forward power flow and buck mode for reverse power flow. Based on a modified zeta converter topology, the proposed converter offers a simplified circuit structure and control strategy, requiring fewer components. It achieves wide voltage gain across an extended duty cycle range while minimizing voltage stress on most switches. A 200-W prototype has been developed and tested in the laboratory to validate the converter’s performance. To enhance efficiency, SiC MOSFETs are utilized, achieving a peak efficiency of 96%. Experimental results confirm the converter’s suitability for both open-loop and closed-loop configurations, highlighting its potential for diverse applications in energy storage systems and EVs. © 2013 IEEE All rights reserved.