A new control strategy for interfacing battery supercapacitor storage systems for PV system

In this paper, a new control strategy is proposed for hybrid energy storage system (HESS) for remote area power supply system consisting of PV, battery, supercapacitor (SC) and load. Since the PV generation and load demand varies continuously, batteries can undergo irregular, partial charge/discharge cycles. It has detrimental effects on battery life span and rating. Therefore in the proposed method, batteries are used to balance the low frequency power surges, because of its low power density and low charge/discharge rates. Whereas SCs are used to balance the high frequency power surges, because of its high power density and high charge/discharge rates. The control of the battery system is coordinated with SC to improve the life span and reduce the stress on battery. The proposed control strategy is compared with the conventional strategy and validated for sudden changes in PV generation and load demand through digital simulation.