Research On Some Problems Of Multiple Time And Space Scale Coordination Of Wind Powerintegrated System

With aggravation of environmental problem and the energy crisis being serious, windpower is increasing day by day, which has brought great challenges to power system. As aresult, much wind power has been abandoned. It’s meaningful to research new multipletime and space scale coordination scheduling method, to cope with variation anduncertainty of wind power. Firstly, based on basic characteristics of wind power, the impactof large scale wind farm on peak load and frequency regulation is analyzed, and somemeasures of improving wind power absorption are presented. Secondly, a method ofmulti-time scale rolling coordination scheduling is introduced. At last, the characteristic ofwind power smoothness across the region in China is studied, and based on portfolio theory,wind power capacity planning among eight wind power base is discussed.Based on the principles of timing progressive, rolling coordination and maximize theabsorption of wind power, a method of multi-time scale rolling coordination scheduling isintroduced. Progressive method among multi-time scale scheduling, allows different timescale scheduling to carry out their own duties well, while taking into account coordinationbetween adjacent time scale scheduling. According to the latest updated prediction resultsof wind power and load demands and actual completion of units energy, three rollingscheduling based on different time scale is applied to revise original scheduling inremaining time. In order to maximize the absorption of wind power, penalty cost of windpower shedding is joined in the objective function of short-term scheduling. A modifiedIEEE118-bus system is applied to test the proposed method.Wind speed data of sixteen areas in China is obtained through GEOS-5DAS. Qualityfactor being evaluation index, wind power resource in the sixteen areas are evaluated andanalyzed. The scatter diagram of wind power correlation coefficient among the sixteenareas vs distance is plotted. Exponential function is applied to fit the diagram and the decayfactor equals562km. Wind power smooth effects among different areas in our country areverified. Return and risk are defined as the average capacity and the standard deviation of windpower output respectively, then wind power capacity planning model is proposed based onportfolio theory. Wind power capacity planning among eight wind power base is discussed,and an efficient frontier is obtained. The proposed model shows great superiority, andprovides a new perspective for wind power capacity planning in China.