Research On Unit Commitment Optimization Considering Wind And Negative Peak Load Regulation Ability

In recent years,the increasing deterioration of the ecological environment and the energy crisis have prompted the vigorous development of new energy power generation.Among these resource generations,wind power generation has a relatively mature technology,and has been widely used in the world.But subject to the characteristics of wind resources,Wind power has very obvious randomness and intermittence.Power system will face great challenges in security and stability,power quality,peak and frequency regulation etc when large-scale wind power connected to the grid.In order to ensure the safe and reliable operation of power system,more spinning reserve capacity would be needed to deal with the uncertainty and anti load characteristics of wind power.The adjustable output of the conventional units in the load trough time would determine the wind power acceptance ability of the system to a great extent.Therefore,the key to keep a large-scale wind power consumption is to solve the problems caused by peak regulation which depends not only on the existing system structure,but also on the development of a reasonable unit commitment scheme.In order to make the system run economically and reliably,this paper studied an optimization method for multi-objective unit commitment considering the system's operation cost and the negative peak load regulation ability of conventional unit in valley load period.This paper firstly analyzed the characteristics of negative peak load regulation of conventional units,and built a model considering the negative peak load regulation ability in valley load period.Secondly,in order to reflect the fluctuation of wind power in the unit commitment problem,a wind power interval prediction method based on nonparametric estimation was presented.Thirdly,a multi-objective unit commitment was built based on operation cost and negative peak load regulation.And a two-stage optimization method considering wind power uncertainty was proposed.In the first stage,the multi objective optimization of unit commitment is carried out by using deterministic wind power prediction value,which the Pareto optimal solution set will be determined.In the second stage,different unit commitment schemes will be evaluated according to the combination of the Pareto solution set and the wind power prediction interval.Finally,the best unit commitment scheme considering system economy and reliability can be obtained.According to the established model,two methods are studied.They are joint optimization method based on discrete particle swarm optimization and predictor corrector interior point method(DPSO-PCIPM)and optimization method based on normalized normal constraint(NNC).Through an example analysis,it is found that NNC method is better than DPSO-PCIPM method.Therefore,the NNC method is used to simulate the 10 units system and its expansion system(the 20 units system).The simulation results show the feasibility of the proposed method,and it can provide a practical optimization scheme for the decision maker.