A Nonisolated Three-Port DC–DC Converter With Two Bidirectional Ports and Fewer Components

This article presents a new nonisolated three-port converter with reduced component count compared with existing reported topologies. This is achieved by developing different power flow graphs and selecting the most appropriate converters arrangement. In addition, as compared to only one bidirectional port in most reported studies, this article considers two bidirectional ports to accommodate applications requiring bidirectional power flow, such as dc microgrid and regenerative braking. The proposed converter is able to work in seven different modes of operation, which cover all possible combinations of power flow among the three ports. Furthermore, seamless and smooth transition, maximum power point tracking, battery protection and output voltage regulation are achieved. Experimental waveforms, particularly for transient responses during mode transition, are reported to verify the proposed TPC.