摘要
现有的套管局部放电测量需要利用套管末屏的接地线,操作复杂,且容易受地网中的脉冲信号干扰。为此,有学者提出了基于特高频阵列信号套管局部放电时差定位遥测法。此方法有效的关键在于准确获取放电源到各传感器间的时间延迟。由于套管各缺陷信号传播路径不同,导致波形有不同的形态特征,现有的方法不适合于各种形态的波形,会造成一定误差。为此,文中研究了基于特高频波形形态的套管局部放电定位时延分析方法。在实验室搭建了110 kV变压器出线套管局放试验平台,制造了3种典型缺陷模型,测量了局放特高频信号,获得了各缺陷波形形态特征,对比分析了现有时延分析方法的适用性。研究结果表明:1对于信号传播路径单一的缺陷,阵列传感器所测信号间相关度高,相关分析法稳定性好、准确度高;2对于信号传播路径复杂,放电源位于油箱内部的缺陷,信号持续时间长,最小能量法稳定性好、准确度高。这些结果对推动套管局放定位有一定指导意义。
Since the procedure of preventive test for bushings is complex and easily interfered by the grounding net, it is difficult to find out earlier defects effectively. Some scholars put forward a novel PD location method for bushings based on TDOA of UHF signals. It is vital that it must access the the features of different signals. This paper makes investigation o by different partial discharges occurred in bushings. Firstly, the Secondly, Finally, TDOA automatically and accurately regardless of n measurement of TDOA of UHF signals radiated classical method in time domain are introduced; methods of TDOA according to the features of UHF signals propagated through various paths are raised; the accuracy of measurement is oroved bv the experiment results. Test results show that： 1）for the signals propagated through unitary path which have higher correlation degree, the correlation method has high stability and good accuracy;2）for the signals propagated through a complex path which show longer duration, especially PDs in the oil barrel, the minimum energy method is more stable and accurate. The research is valuable and meaningful to PD location for bushings.
出处
《高压电器》
CAS
CSCD
北大核心
2016年第4期180-187,共8页
High Voltage Apparatus
关键词
套管
局部放电
特高频定位
时延分析
bushing
partial discharge
UHF location
time delay analysis
