A Novel Bidirectional Modified Zeta Converter With Wide Voltage Conversion Ratio

High-gain, non-isolated bidirectional DC-DC converters play a vital role in interfacing energy storage systems with microgrids and electric vehicles. However, existing converters often operate within a limited duty cycle range and involve high component counts and significant voltage stress for achieving desired voltage gains. This paper presents a novel non-coupled high-gain bidirectional DC-DC converter that efficiently operates in 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 electric vehicles.