Optimal Sizing of Battery Energy Storage System for Smoothing Power Fluctuations of a PV/Wind Hybrid System

Abstract

Abstract This paper presents an approach to size the battery energy storage system (BESS) for the suppression of the output power fluctuations in a solar photovoltaic (PV)/Wind hybrid energy system. The strategy presented uses a dynamic averaging technique, with a different number of samples in order to produce different smoothing levels in the output power. The key advantage of the proposed strategy is that, apart from sizing the BESS, the same strategy can be implemented in real time to perform the energy management for the system. The gravitational search algorithm (GSA) has been used to find the optimum size of the BESS which will be able to produce the required level of smoothing. The effectiveness of the proposed strategy has been verified through a case study presented and the results indicate that the strategy is effectively able to size the BESS for reduced power fluctuations from the system. To verify the robustness of the proposed strategy, the uncertainty in the climatic conditions has also been considered and the results indicate that the proposed strategy works well even in the case of a change in the climatic conditions.