Coordinated Control Strategy and Economic Analysis of Flywheel Energy Storage Array for Wind Power Suppression

Abstract

With the increasing proportion of wind power connected to the grid, the randomness and fluctuation of its output power have an increasing impact on the stability of the grid, and there is an urgent need to smooth out its output power fluctuation. First, an unit model of IMW /0.25MWh flywheel energy storage (FES) is established and its charging and discharging characteristics are analyzed. Then, based on the improved wavelet packet decomposition and T Location-Scale (TLS) distribution method, a FES array capacity configuration method is proposed to determine the required capacity and power of FES array. Then, based on the proportional power distribution of FES units and the charge state control method, a coordinated control strategy for the FES array is proposed to mitigate wind farm power fluctuations, optimize power convergence in each FES unit, and maintain a reasonable charge state. Then, the economic model of wind farm and FES array is established. Finally, based on the operational data of a 15 MW wind farm, the proposed control strategy is simulated and validated, and the economics of the wind farm and FES array are analyzed. The results show that with this control strategy, the wind farm grid-connected power fluctuations can be achieved as specified. Relative to the system without energy storage, this method reduces the maximum output power fluctuations of the wind farm by 50.17% and 6.32% for 1 min and 10 min, respectively, and increases the annual revenue by 15%.