Application of battery-supercapacitor energy storage system for smoothing wind power output: An optimal coordinated control strategy

In the application of energy storage for smoothing wind power output, the combination of battery and supercapacitor (SC) is considered as an effective alternative to improve the battery lifetime and enhance the system economy. In this paper, third-order Butterworth low-pass filter and high-pass filter are adopted to smooth the wind power and allocate power between battery and SC. Then, an optimal coordinated control strategy is proposed to determine the cut-off frequencies of the two filters and the power sharing between battery and SC. With this strategy, the total deprecation cost of the system caused by charge/discharge is minimized while satisfying the requirements of wind power integration. Finally, the effectiveness of the proposed method is demonstrated with a simulation study.