In order to analyze the influential factors of the energy storage size accurately with wind power fluctuation mitigation

we adopted a model predictive control（MPC） method as the control strategy with the identical grid-connected fluctuation rate constraints. Firstly

different fluctuation rate constraints and fluctuation mitigation sequences were considered

and the reasonable fluctuation rate and mitigation sequences could be obtained. Additionally

different time scales of wind power and state of charge（SOC） of energy storage were analyzed

and the credible energy storage capacity could be acquired. Finally

the wind power with different amplitudes and frequencies was analyzed

and the wind power type with larger energy storage capacity could be identified. The simulation results show that different energy storage sizes are required according to different fluctuation rate and mitigation sequences. Energy storage size is related to the maximum wind power fluctuation rate and the maximum energy change of energy storage besides initial SOC and SOC operating range of energy storage. The wind power with larger fluctuation rate and low frequency generally needs more energy storage size.