The invention discloses a 
capacity optimization and auxiliary peak regulation method for a regional 
wind power plant group 
energy storage power station. The method comprises the steps that 1, a BESS (
battery energy storage 
station) 
composite function charging and discharging realizing method of 
wind power plant group 
power fluctuation stabilization and power network peak regulation is considered, and a 
capacity optimization calculating model is built by using the BESS operation cost minimization as a target; 2, the super-short-term 
wind power is utilized for predication, and a real-time optimization 
operation model is built by using the maximization of gains when the BESS synchronously participates in the 
power fluctuation stabilization and the power network peak regulation as a target; 3, the 
cost sharing and 
gain distribution mode and method of the BESS 
system operation are provided. Through the adoption of the technical scheme, an 
energy storage system with the configuration required by a regional wind power 
plant can be planned, the economic and reasonable 
energy storage capability is optimized and calculated, meanwhile, an prioritization scheme that the energy storage 
system participates in the power network peak regulation in an auxiliary way is provided, and the reasonable and efficient operation level of a regional 
wind field configuration energy storage system is improved.