Models Of Wind Power Farm Considering Wind Speed Correlation And Application In Reliability Evaluation Of Generation And Transmission System

With the exhausting energy and more severe environment problems, thedevelopment and utilization of wind energy have received considerable attentions inrecent years. However, the wind energy is unstable and multi-variable energy source,and a large-scale integration of wind farms has a significant effect on the reliability ofpower system in a different manner of conventional energy sources. In China,Theextensive utilization of wind energy also brings the integration of multiple wind farmsinto power systems in a region. Due to the geographic locations of wind farms, windspeeds at different sites present certain dependence between each other, which has aconsiderable impact on the reliability of power systems with wind energy. So thatoutput characteristics from multiple wind fams are different from single wind farm,Therefore, it’s necessary to analyze the joint distribution for outputs from multiple windfams. Without taking wind correlation into consideration may lead to a severeunderestimation of the variability of the system power flows and consequently anunderestimation of the risks related to the specific design decisions. Therefore, it’simportant to conduct in-depth study on the effect of large-scale integrated wind powerand the reliability of power systems containing wind energy.In order to investigate, measure and establish the model of stochastic dependence,Copula theory and mixed Copula theory can be used for the models of dependence.The case study shows the application of the technique for the study of the large-scaleintegrations of wind power in Jiuquan, Gansu Province.Firstly, both Weibull distribution function of parametric model and kernel densityestimation (KDE) method of nonparametric model are adopted in this paper tocharacterize the probability distribution of wind speed, and summarize the estimationsfor parameters of the model to get the probability distribution of wind speed from asingle farm.Secondly, according to the fundamental theory of Copula function and thecharacteristic analysis for the wind speed from multiple wind farms, the Copulafunction is introduced to characterize the Joint Probability Distribution of wind speedfrom multiple wind farms. And put forward the advantage of fit testing method, so as toprovide a powerful tool to characterize the Joint Probability Distribution and depicte its tail correlation for wind speed from multiple wind farms.Lastly, based on the power output function of the wind-turbine, a reliabilityevaluation model of Generation and Transmission system containing multiple windfarms is proposed on the basis of Monte Carlo simulation method, which can be used toconsider the negative effect of wind farm and the outage of wind turbine generators.The results show that the model can be directly used to evaluate the reliability effect onthe power systems containing wind farms.