基于风电场功率特性的风电预测误差分布估计

Estimation of Error Distribution for Wind Power Prediction Based on Power Curves of Wind Farms

风电功率预测对风电场运行和电网调度决策具有重要影响。基于风电场的功率特性曲线,提出了一种风电预测误差分布的估计方法。首先根据历史运行数据对风电场的功率特性曲线进行拟合;然后按照风电场的切入风速和额定风速将历史实测数据划分为3部分,并利用改进后的广义误差分布等模型提取每一部分风电功率预测误差的概率密度特性,根据其数值特征,设定相应的风电功率修正方法和预测误差分布的估计方法;最后按照待测日预测风速的大小选择对应的修正方法补偿所预测的功率,并估计预测误差的分布范围。结合中国北方某风电场的实际运行数据进行了仿真算例分析,验证了所提方法的有效性。

Wind power prediction plays an important role in wind farm operation and power grid dispatching. Based on power characteristic curve of wind farm, an estimation method for wind power prediction error distribution is proposed. Firstly, according to historical operation data, the power characteristic curve of wind farm is fitted. Then the historical data are divided into three parts according to cut-in wind speed and rated wind speed, and probability density characteristics of wind power prediction error are extracted with improved generalized error distribution model. Combined with its numerical characteristics, corresponding wind power correction method and estimation method of the prediction error distribution are set up. At last, corresponding correction method is chosen to compensate wind power, and distribution range of the prediction error is estimated according to magnitude of forecasting wind speed. Case study based on actual operation data of a wind farm in Northern China shows that the proposed method is effective.