An integrated four port bidirectional dc-dc converter for photovoltaic energy harvesting systems

Abstract

In this paper, an integrated four port DC-DC converter with bidirectional power transfer capability is proposed for connecting two photovoltaic sources with an energy storage element to a dc load. This converter achieves high power density due to its integrated structure and device sharing feature among the ports. Adopted PWM and secondary side phase-shifting control eliminates the circulating current and its associated conduction losses and minimizes the current ripple at input ports. Further, it simplifies the complexity of control by decoupling the control variables of input and output ports. Working of the converter under different operating conditions are verified with a 500-W experimental prototype.