Research On Robust Optimal Dispatch Of Power Systems Considering Large-scale Wind Power

Wind energy is a kind of important renewable energy.In order to promote the development and utilization of wind energy,the scale of wind power integration increases dramatically.However,the strong fluctuation and intermittence of wind power brings greater challenge to the dispatch of power systems.Meanwhile,with fast expanding of power systems,the interconnection of regional power systems becomes closer and closer.It's necessary to protect the information privacy of regional power systems in the process of exchanging information for optimal dispatch.In order to deal with the uncertainty of wind power,robust optimization is applied in this paper.The uncertainty of wind power is converted into the boundary information of the prediction interval.And the robust dispatch model of power systems is formulated based on the affine adjustable robust optimization technique.The automatic generation control unit is used to cope with the fluctuation of wind power.The objective of the model is to minimize the sum of operating costs of AGC and non-AGC units,which considering unit operation constraints,wind power constraints,system power balance constraints and line capacity constraints.It ensures the system can operate safely when large-scale wind power integration.For the requirements of information privacy and dispatch independence of each area,the proposed centralized robust optimization model is decoupled according to the dynamic programming theory.The influence of one area's decision on other areas is described by the value function,and then the robust dispatch sub-model for each area is obtained.The submodels are solved iteratively by using approximate dynamic programming.Finally,the tests are carried out in the 2-area 6-node system and the actual 4-area 2298-node system.The results indicate the accuracy,rapidity,and stability of the proposed approach for solving the decentralized robust optimal dispatch.Wind power output has the characteristic of longer dispatch period and lower prediction accuracy.The paper formulates a day-ahead robust dispatch model based on the output range of wind farms can be absorbed.The model considers the integration of large-scale wind power and energy storage to power systems.Moreover,the absorbed wind power interval and the participation factors of adjustable units and energy storage are considered as the decision variables.The system controls the operation of wind turbines within the absorbed output range.Adjustable units and energy storage can reasonably deal with the fluctuation of wind power according to the optimized participation factors.Finally,the simulation results show the proposed method can improve the economics of power systems while ensuring the robustness.