Soft-switching isolated tri-port converter for integration of PV, storage and single-phase AC grid

Abstract

This paper presents a single-stage isolated softswitching tri-port converter for integrating a renewable resource like solar PV, and energy storage with single-phase AC grid through high-frequency galvanic isolation. The single-stage approach reduces the component count, and the full-range softswitching feature realizes higher efficiencies compared to the state-of-the-art methods. A significant advantage of the proposed topology is the elimination of DC capacitors which are major life limiting components in a PV inverter. The tri-port converter can be designed to connect to single-phase or split-phase AC grids, realizing soft switching across the entire range of operating load levels. This paper presents the concept, principles of operation and control, and verification through simulation and experimental results of the proposed tri-port converter.