Stand-alone photovoltaic generation system with combined storage using lead battery and EDLC

This research is mainly concerned with a stand-alone photovoltaic (PV) generation system for low power DC applications placed where the commercial AC grid connection is not supported. In this paper, basic and improved circuit topologies and the control schemes of stand-alone photovoltaic generation system are proposed. To prevent battery from deep discharge, electric double layer capacitor (EDLC) is incorporated into the proposed systems as combined energy storage device in parallel with conventional lead battery. The fundamentals of operating performances and effectiveness of proposed stand-alone PV system are illustrated and evaluated on the basis of a practical point of view.