风电场风速分布特性的模式分析

Pattern Analysis on Characteristics of Wind Speed Distribution in Wind Farms

目前的风电场风速分布特性分析主要服务于风电场规划或电能计划,通常由较长时间内的风速采样数据统计得到。然而,当需要应对更短时间、特别是与运行和控制时间级有关的问题时,服务于规划或电能计划的风电场风速分布特性已不能完全适应新的需要。从不同的应用环境出发,探讨了风电场风速分布特性的模式化差异及可能造成模式化差异的主要原因,并从风速概率密度和条件风速概率密度分布中提取出特征风速、形状系数、尺度系数、概率偏度等指标,以考察不同风速分布所表现出的模式差异性。某实际风电场风速分布特征分析结果表明:从不同角度统计的分布特性存在明显的模式差异性;风速分布特性用于解决不同问题时,需要采用与其对应的统计规律。

At present the analysis on the characteristics of wind speed distribution, which is generally obtained from the statistic of sampled wind speed data, is mainly serviced to the wind farm planning or electric energy planning. However, the characteristics of wind speed distribution serviced to above-mentioned planning fields cannot fully cope with the demands under new conditions, such as the characteristics of wind speed distribution in shorter time periods, especially in those short time periods related to the operation and control of power grid. Based on different application environments, the patternized differences of characteristics of wind speed distribution in wind farm and main causes that may lead to the patternized differences are discussed, and from the probability density of wind speed as well as from the probability density distribution of conditional wind speed the indices, such as characteristic wind speed, shape factor, scale coefficient and probability deviation and so on, are extracted to observe and study the patternized differences due to different wind speed distribution. Results of analysis on characteristics of wind speed distribution in an actual wind farm show that there are evident patternized differences among the characteristics of wind speed distribution from the statistic based on different viewpoints; when characteristics of wind speed distribution is applied to solve different problems, it is necessary to choose the statistical law conforming to the problem.