Analysis Of Load Forecasting Credibility And Its Application In Island Power System Optimal Dispatch

Island power supply system is a special microgrid. In island power supply system,volatile power resources take up a large proportion, the randomness of network supply loadand the uncertainty of operation increases, and natural disaster such as typhoon can easilyaffect its operation. Therefore, this paper puts forward credibility forecast of loadforecasting. According to credibility forecast results, the dispatching time scale can beadjusted. Then, the uncertainty of power system can be reduced and the economy of it canbe improved.Research work can be as follows in this paper.First of all, this paper analyzes the differences among island power supply system,traditional bulk power grid and microgrid. Then, the framework of island power supplysystem is researched and the framework of advanced applications in island power supplysystem EMS is proposed.Secondly, this paper puts forward the credibility assessment method. The credibility ofload forecasting mainly depends on forecasting errors and the regulation of forecastingerrors will be analyzed. Also, this paper proposes the credibility index to assess short-termload forecasting. By using analytic hierarchy process, the comprehensive credibility indicecan be obtained. Towards ultra short-term load forecasting result, the credibility indice toassess ultra short-term load forecasting is also proposed. The linguistic variables forcredibility levels can be built according to different credibility values. Through case study,the feasibility of credibility assessment can be verified.Then, this paper presents the credibility forecasting method. Improved geneticalgorithm neural network forecasting method is adopted to forecast the credibility ofshort-term load forecasting and ultra short-term load forecasting. Base on the actual powergrid data, the feasibility of credibility forecast can be proved.Finally, the dispatch is optimized by considering total cost as objective function. Dueto the randomness of wind power, photovoltaic power and load, the Monte Carlo method isadopted. Therefore, in the situation of different credibility level and different fluctuations ofwind and photovoltaic power, the total cost can be calculated. In accordance with thecredibility of short-term load forecasting and ultra short-term load forecasting, thecorresponding dispatching time scale adjustment method is proposed.In this paper, the assessment and forecasting method of load forecasting credibility is analyzed, and its application in island power supply system optimal dispatches is alsoresearched. It can improve the security and stability of power grid and it is meaningful forthe economy operation of power system.