Hybrid flywheel-battery storage power allocation strategy for smoothing wind power fluctuations

Power fluctuations in wind power generation, due to its stochastic and intermittent nature, have become a significant challenge for power system stability and grid integration. To address this issue, this paper proposes a hybrid energy storage-based power allocation strategy that combines flywheel and battery storage systems to smooth wind power fluctuations and enhance grid acceptance. First, the self-adjusting sliding average filtering method is applied to smooth the wind power for grid integration. To overcome the subjectivity and empirical issues in parameter selection of the existing variational mode decomposition (VMD) algorithm, a successive VMD method is proposed. This method decomposes and reconstructs the wind power to achieve the initial power allocation of the hybrid energy storage system (HESS). Furthermore, double fuzzy control is employed for secondary power command allocation to ensure the energy storage devices maintain a reasonable state of charge and avoid excessive charging/discharging. Finally, simulations based on wind farm data from a region in Qinghai are conducted using MATLAB/Simulink, and the results demonstrate that the proposed strategy effectively mitigates wind power fluctuations and achieves optimal power decomposition and reasonable allocation in the HESS.