Study on Hybrid Energy Storage Power Allocation Strategies for Smoothing Wind Power Fluctuations

To solve the wind power fluctuation problem caused by hybrid energy storage system (HESS) connected to wind farms, a HESS power allocation strategy scheme was proposed to control variations in wind power. First, the limiting average filtering algorithm was used to filter the raw wind power and the grid-connected power and HESS reference power complying with the grid connection standard were calculated. Then, the Osprey-Cauchy-Sparrow Search Algorithm (OCSSA), which integrates the osprey and Cauchy variants, was used to optimize the Variational Mode Decomposition (VMD) parameters K (the quantity of modes) and $\alpha$ (the penalty component). After the optimal parameter combination [$K, \alpha$] was obtained, the HESS reference power was decomposed into high and low-frequency power constituents by VMD, which were allocated to the supercapacitor and the battery. The numerical example results showed that the proposed HESS power allocation strategy can effectively improve the economic efficiency of HESS.