| In recent years,with the extensive use of fossil energy,energy and environmental problems are becoming increasingly serious,vigorously develop wind,light,water and other renewable energy has become a broad consensus of countries around the world,the construction of clean,low-carbon,safe and efficient modern energy system,the construction of new energy as the main body of the new power system has become an inevitable trend.However,the volatility and uncertainty of wind power output will not only increase the difficulty of its consumption,but also threaten the safe and stable operation of the power grid.Energy storage devices can effectively reduce the uncertainty of wind power output.As a means of energy transfer in time,energy storage facilities can be introduced into wind farms to form a wind storage joint system,which can effectively calm the uncertainty of wind power output and become an effective way to solve the above-mentioned problems.As a new type of energy storage,gravity energy storage can realize the conversion between electric energy and gravity potential energy by lifting and releasing heavy objects,which has the advantages of high charge and discharge efficiency,low kilowatt-hour cost and environmental friendliness.In this paper,gravity energy storage is introduced into wind farms,and a combined system of wind farms and gravity energy storage is proposed.On this basis,considering the uncertainty of wind power output,a data-driven ensemble robust optimization model is constructed to optimize the operation of the wind farm-gravity energy storage combined system from two stages:day-ahead scheduling stage and real-time adjustment stage.The two-stage data-driven set robust optimization model proposed in this paper is transformed into the corresponding two-stage optimization problem to reduce the complexity of the model operation.Five simulation scenarios were designed for comparative analysis to verify the advantages of gravity energy storage,a new form of energy storage,in reducing the uncertainty of wind power output and improving the economic benefits of the system,as well as the advantages of the proposed two-stage data-driven ensemble robust optimization model in operational efficiency and computational complexity.And then put forward the operation optimization strategy of the combined wind storage system.The comparative analysis of the simulation results shows that:(1)the introduction of gravity energy storage device can effectively reduce the uncertainty of wind power output and smooth the fluctuation of wind power output;(2)Gravity energy storage is more economical than traditional energy storage forms such as chemical energy storage(26.52%higher than chemical energy storage),and can improve the economic benefits of wind farms to a greater extent;(3)The two-stage datadriven ensemble robust optimization model has better solving performance than the stochastic optimization model and the deterministic optimization model.It can resist the interference of wind power output uncertainty,and keep conservatism and computational complexity at a low level.Through this paper,we can obtain the optimal operation results of the wind farm-gravity energy storage combined system,realize the optimal scheduling of gravity energy storage devices,minimize the wind abandonment,thus improve the utilization rate of wind energy and other renewable energy sources,maximize the economic benefits of the operation of the wind-storage combined system,and develop an operation optimization strategy for the future wind-storage combined system,which has a certain reference value for the future energy storage devices,wind-storage The research,development and layout of the combined wind storage system have certain reference value. |
