2地点における日射変動のコヒーレンスとアンサンブル平均値に基づく地点間距離と日射変動独立性との関係評価

概要

論文の詳細を見る
Power output fluctuation of high penetration photovoltaic power generation systems (PVSs) may cause negative impacts on the load frequency control (LFC) of an electric power utility. For the cost-effective mitigation, the proper evaluation of apparent electricity demand fluctuation is important, taking the power output of PVSs into account as a negative demand. If the actual power output patterns are independent among several points, the standard deviation (STD) of total power output fluctuation of PVSs located in several points can be estimated based on the addition theorem of variance. Moreover, the central limit theorem may be applied if the probability distribution of insolation fluctuation is the same among several points. As a fundamental study to apply the stochastic methods, this study evaluates the following two factors to determine the distance between two points with which the insolation patterns of two points can be considered as independent: 1) the coherence of insolation fluctuation for various combinations of two points with different distances, 2) the correlation diagram of two different STDs, i.e. the STD of ensemble average insolation fluctuation observed at two points and the averaged STD of each STD of insolation fluctuation at two points. The results suggest that the insolation fluctuation consisting of the cycles shorter than 30min can be considered as independent if the distance between two points is longer than 5km-10km.