基于概率统计的南方电网主网电压质量分析

Analysis on the Voltage Quality of CSG’s Main Network with Probability Statistics

针对现有电压分析方法的不足,提出了基于概率统计的主网电压质量分析方法,从电压的数学期望、标准差估计及概率密度曲线来分析其质量。应用所提出的方法,计算大理站、砚山站、盘南电厂等7个典型厂站2009年1月、8月的电压均值、标准差及概率密度曲线,所得的分析结果与现行方法比较说明,电压均值指标较电压最高、最低值更加准确反映整体电压水平,电压标准差指标较电压最高、最低值之差更加准确反映电压波动程度,电压概率密度曲线较电压合格率更好地区分电压质量高低。

Aiming at the insufficiency of traditional methods for voltage quality analysis,and based on probability statistics,this paper proposes a novel method for analyzing main power network.The proposed method does analysis with the mathematical expectation,standard deviation and probability distribution curve of voltage.The average values,standard deviations and probability distribution curves of voltage in seven typical power plants/substations such as Dali Substation,Yanshan Substation,Pannan Power Plant etc.in January and August,2009 are calculated with the propposed method.In comparison of the results between the proposed and currently methods,it proves that for the overall voltage level,the average value is a better index than the highest and lowest values;for the voltage fluctuation level,the voltage standard deviation is better than the difference between the highest and lowest values;for the voltage quality,the probability distribution curve is better than the pass percent of voltage.