高压直流换流站瞬态电磁骚扰特征的小样本统计方法

由于在高压直流换流站中开关操作的次数是有限的,因此在换流站现场测量到的瞬态电磁骚扰数据也十分有限,这时针对大样本的传统统计方法已经不再适合,需要采用小样本统计方法进行分析。首先介绍了2种近来广泛应用的小样本统计方法,然后通过实例分析总结了它们对处理小样本问题的优越性。最后针对某换流站继保小室的瞬态电磁骚扰测量数据,应用随机加权法得到了瞬态骚扰特征值的统计结果。分析瞬态电磁骚扰的特征有利于评价换流站内电磁骚扰的总体水平,提出或完善二次设备的瞬态抗扰度标准。

Small Sample Statistics for Transient Electromagnetic Disturbance Characteristics of HVDC Converter Stations

In view of limited operation times of circuit breakers in HVDC converter station,there was limited data of transient electromagnetic disturbance measured in the converter station and for such an occasion traditional statistics for large samples was no longer applicable,so it was necessary to adopt small sample statistics for the analysis.Firstly,two kinds of recently widely applied small sample statistical methods were presented;then through case study the superiority of the two methods in processing small sample problems was summarized;finally,according to measured data of transient electromagnetic disturbances in relay protection chamber of a certain converter station the statistical results of characteristic values of transient electromagnetic disturbances were attained by random weighting method.Analyzing characteristics of transient electromagnetic disturbances was favorable for the assessment on total level of electromagnetic disturbances within converter station as well as for proposing or perfecting the transient noise immunity standard for secondary equipments.