Capacity Configuration Method of Hybrid Energy Storage System for Stand-Alone Photovoltaic Generation System

To enhance photovoltaic (PV) utilization of stand¬alone PV generation system, a hybrid energy storage system (HESS) capacity configuration method with unit energy storage capacity cost (UC)and capacity redundancy ratio (CRR) as the evaluation indexes is proposed, which is considering different types of load. First, the HESS power difference between the load demand power and the PV output power is obtained by the method, which is allocated by the low-pass filtering algorithm. According to the characteristics of power type and energy type energy storage device, the low frequency component is borne by the energy-type energy storage device, and the high-frequency component is borne by the power-type energy storage device, taking HESS charging and discharging efficiency, SOC upper and lower limits and capacity attenuation as the constraints. Then, based on the whole life cycle cost, analyzing the different effects of different PV power generation energy and load types on the indexes. Finally, the feasibility and effectiveness of this method are analyzed by 3 actual examples.