Optimal sizing of the hybrid energy storage system aiming at improving the penetration of wind power

Wind power has the inherent characteristics of random fluctuation and intermittence, which bring adverse effects to system's steady operation and security, and restrict the penetration of wind power to integrate to the power grid. Based on the analysis of different kinds of energy storage system, a hybrid energy storage system (HESS) composed of super capacitor (SC), battery energy storage system (BESS) and pumped storage power station and its optimal sizing method are presented to inhibit the adverse effects of wind power on power grid. BESS and SC are used to mitigate the wind fluctuation, and pumped storage power station is used for peak regulation. Taking the investment and operation costs into consideration, the optimal capacities of HESS can be determined. Based on the modified IEEE RTS-96 system and the actual power output of wind farm, the proposed method is verified. The results prove the effectiveness of the proposed method and it can improve the penetration of wind power with the power system operating the most economically.