Study On A Control Strategy For Energy Storage Based On Feasible Operation Region Of Wind Power And Life Attenuation

The development of wind power is an effective means to promote energy transformation and improve the eco-environment in China.However,due to the random fluctuation characteristic of the wind power,its large-scale interconnection brings severe regulation burden to the power grid.In order to ensure safe and stable operation of the power grid,the wind power output is usually limited,thereby limiting the ability of power grid to accept wind power.Energy storage can effectively improve the ability of power grid to accept wind power because of its fast response characteristic and energy migration characteristic.But at present,energy storage is expensive and its cycle life is insufficient,so how to configure the capacity of energy storage and formulate the control strategy of energy storage so as to improve the ability of power grid to accept wind power and prolong the service life of energy storage,which have become the main direction of research in the industry.Firstly,based on the fluctuation characteristic of the wind power,the output power trend of wind farms with different installed scales is analyzed,and then the convergence effect is revealed.At the same time,aiming at the phenomenon of charging on one side and discharging on the other side when the distributed energy storage regulates the wind power,the energy cancellation effect of distributed energy storage is revealed when regulating the wind power.In order to reduce energy waste,the centralized energy storage should be adopted.Secondly,based on convergence effect and cancellation effect,considering benefit of energy storage and effect of life attenuation comprehensively,a energy storage capacity configuration method is proposed for extending the feasible operation region of wind power to maximize the net benefit of energy storage within the planning year,the case study proved that the method can improve the ability of power grid to accept wind power.Finally,to improve the ability of power grid to accept wind power and extend the service life of energy storage,a control strategy of energy storage based on the feasible operation region of wind power and fuzzy optimization is proposed in this paper.This strategy aims at the problem that the conventional control strategy of energy storage usually has more deep charge and deep discharge,which leads to excessive life loss.Considering the real-time feedback of the SOC and the constraints of the charging and discharging power,the charging and discharging power of the energy storage is optimized to prolong the service life of the energy storage and regulate the wind power effectively for a long time.The results of engineering examples show that compared with the conventional control strategy,the optimized control strategy can effectively improve the operation status of the energy storage and reduce the life loss.This research has a certain value for improving the ability of power grid to accept wind power,and has important engineering significance for planning and controlling of energy storage.