主元分析结合Cornish-Fisher展开的半不变量法概率潮流计算

为克服现有半不变量法概率潮流计算( probabilistic load flow based on cumulant method ，PLF-CM)不能处理输入随机变量相关系数矩阵非正定之不足,提出一种基于主元分析和半不变量法结合Cornish- Fisher 展开的PLF -CM计算方法。新方法根据输入变量的离散样本数据求取输入变量的半不变量,利用主元分析处理关联性输入随机变量以准确计算输出变量的半不变量,采用Cornish- Fisher级数求得电力系统的概率潮流分布。在改造后的IEEE-14节点测试系统.上进行的仿真研究表明:所提方法计算高效、稳定,适用于不确定性较大的新能源电力系统的概率潮流分析。

Cumulant method for solving probabilistic load flow based onprincipal component analysis and cornish - Fisher expansion

To overcome the deficiency that the existing probabilistic load flow based on cumulantmethod ( PLF-CM) cannot deal with the non positive definite coefficient matrix of random input vari-ables, a novel PLF-CM method based on principal component analysis ( PCA) and cumulant methodtogether with the Cornish-Fisher series expansion is proposed. The new method computes the semi -invariants of input random variables by using sample data. The PCA method is used to deal with the input variables with relevance to accurately obtain semi-invariants of output variables. Finally, theCornish-Fisher series expansion is used to calculate the characteristics of power flow distribution.Simulation researches on the modified IEEE 14-bus test system show that the proposed method is simple, efficient and robust hence is suitable for the analysis of the PLF in new energy power systems with large uncertainties.