Research On Control Strategy Of Wind Farm Group Energy Storage System To Improve Wind Energy UTI-lization Level

In recent years,China’s installed wind scale continuous rapid development of new wind power grid installed nearly three years the average growth of 26%,at present our country ten thousands were planning kilowatt wind power base,and centralized distribution in northeast,north,northwest and in the end of the Inner Mongolia power grid and other regional power grid,the region’s power grid structure is relatively weak,load ability is limited,interregional transmission ability and the coordinated ability is insufficient.Compared with single wind farm,the output of wind power cluster is more complex in time and space,which leads to insufficient consumption of wind power by power grid.Therefore,improving the utilization level of wind energy has become a growing concern of people.Energy storage system with fast response speed,and the advantages of convenient installation,easy to expand,the wind that intermittent,volatility strong renewable energy becomes the controllable and adjustable,in view of the investments in the energy storage system is expensive,so under the condition of the energy storage system configuration to determine,the improvement of the energy storage system for wind farm group given level will depend on the energy storage system control strategy research.First of all,this paper analyzes the utilization level of power grid wind power in regions with high wind power penetration.With first years volatility of different scale of wind farm output curve analysis,and analysis of wind farm group of abandon the wind conditions in each time and seasonal change trends,and then analyzed the influence of the large cluster for wind power grid load,and the thermal power unit,demand response（DR）group of resources and energy storage system for large wind farms given wind conditions,As the entry point of the research content,it leads to the research work.Secondly,from the perspective of wind energy utilization level,based on the service life of the energy storage system,charging and discharging efficiency,investment cost and configuration and other factors,taking the annual net return rate of energy storage and wind abandon absorption rate as evaluation indexes,a double-layer optimal control strategy of the energy storage system for improving the utilization level of wind energy is proposed.The economic and effect analysis of the two-layer optimal control strategy of the energy storage system under typical response scenarios and the economic and absorbing effects of the energy storage control strategy under different wind abandoning coefficients of wind farms are analyzed by numerical examples.Finally,energy storage system for wind farm group allocation to the problem of expensive cost,based on wind power given benefit from the power supply side,the lateral load and energy storage system three aspects to consider double scheduling model is established,and according to the scheduling model given the proceeds,thermal power unit climbing constraints,lateral load demand response ability and energy storage system response speed,An optimal scheduling strategy of "source-load-storage" based on the consumption benefit of wind power was proposed.Upper scheduling model relies mainly on the demand response resource optimize the system load,in order to reduce the system peak valley load difference,the lower scheduling model based on the rolling scheduling method with the goal of maximizing the system operation efficiency in the scheduling cycle scheduling model choice,if selected to lateral load scheduling model,need again for two kinds of DR scheduling resources allocation given to abandon the wind power,An example is given to analyze the economy of the optimal source-load-storage scheduling strategy.