局部放电UHF脉冲干扰的排除与信号的聚类分析

为了排除变压器局部放电信号中的各种信号干扰中的脉冲干扰信号,提出了利用内外信号对比法及相间信号对比法排除外部脉冲型干扰信号,并应用于500kV三相分体式变压器的局部放电现场监测。通过提取工频周期上特高频检波脉冲信号的特征参数,选取脉冲初始相位、平均脉冲幅值、脉冲次数3个特征参数,采取灰聚类与模糊聚类相结合的方法对排除干扰后的数据进行了聚类分析,实现了对部分干扰信号的排除以及特高频信号的分类。对分类后的疑似放电信号的现场特高频检波信号进行统计分析,通过分析PRPD谱图对变压器的局部放电活动做出了诊断说明。通过分析表明,提出的方法能够有效排除干扰信号,便于提取局部放电故障信息。

Pulse Interferences Elimination and Classification of On-line UHF PD Signals

In order to eliminate pulse type interference signals in transformer partial discharge signals,an inside-outside signal antithesis method and inter-phase antithesis method were proposed to exclude external pulse type interferences,and were used to on-line UHF PD monitoring system of a 500 kV three-phase split type power transformer. The characteristic parameters including pulse initial phase,average pulse amplitude,maximum pulse amplitude,pulse number from the UHF enveloped signal in power frequency period ...