Determination of Hybrid Energy Storage System Capacity based on Empirical Mode Decomposition for a High PV Penetrated Standalone Microgrid

Abstract

This paper targets to introduce a novel approach for capacity determination of a hybrid energy storage system (HESS) of a standalone microgrid with high PV penetration. The imbalance power between solar PV and load is decomposed to yield its frequency-time components using Empirical Mode Decomposition (EMD) technique. Statistical characteristics of the components are then matched against the attributes of the energy storage devices, namely the electrochemical battery and supercapacitors. This is to achieve the collective benefit of the two storage media in their unique power and energy handling capabilities. This integrated approach is utilized to smoothen the PV variations in the most cost-effective manner. Concurrently, a proposed design procedure is used to determine the storage capacities of the hybrid energy storage system to avoid penalty of un-met load.