A stand-alone photovoltaic DC mini-grid with novel semi-active hybrid energy storage system for isolated areas

The solar PV power system is one of the auspicious arrangements for isolated areas which is broadly applied to supply electricity for elementary domestic requirements. Solar energy systems usually coordinate integrated energy storage equipment's, normally batteries used to repay the supply demand incongruity due to the characteristic of solar energy. However, the rapid lifespan of batteries rises the operational expenses of solar energy system. The battery-supercapacitor hybrid energy storage system has been proposed by researchers to extend the lifespan of the batteries. This paper analyzed the different types of battery supercapacitor hybrid energy storage system (HESS) methodologies and discusses appropriate methods that have improved the lifespan of battery in a stand-alone PV DC mini-grid. Furthermore, the state-of-charge (SoC) characteristics of supercapacitor and battery were determined and compared.