Topology Analysis and Review of Three-Port DC–DC Converters

In order to realize power flow control among photovoltaic (PV) panel port, battery port, and load port in the distributed photovoltaic power generation system, integrated three-port dc-dc converters (TPCs) are widely adopted. The objective of this article is to provide a comprehensive, comparative, and insightful analysis and overview of these TPCs. First, based on the power transmission and control requirements of the system, five topological structures of three-port dc-dc conversion system (TPCS) composed of two or three two-port dc-dc converters are presented. And the five structures are comparatively analyzed. Second, based on these topological structures, and combing with the basic two-port dc-dc converters, three groups of typical TPCs with different galvanic isolation requirements are derived, respectively, by sharing switches, combining branches, etc., And comprehensive analysis, comparisons, and reviews of these TPCs with different structures of each isolation type are presented with tables and figures. Finally, the comparison results of the three isolation groups are summarized, which leads to a guidance for the selection of TPCs in different applications, and then some suggestions for the future research on TPCs are given.