一起GIS固体绝缘件局部放电缺陷的定位与分析

Localization and Analysis of a Partial Discharge Defects in GIS Solid Insulation

随着电气设备状态检修工作的开展,带电检测技术在输变电设备状态检测中发挥了越来越重要的作用。文中介绍了利用带电检测技术发现的一起GIS柱式绝缘子内部气隙放电缺陷的定位与分析过程,首先利用特高频法局部放电检测技术,结合谱图特征对放电类型进行了确认;随后利用高速示波器各通道信号到达的时延同时结合设备内部结构,对缺陷位置进行了精确定位;最后对异常位置绝缘件进行X射线数字成像检测及局部放电测量,发现其内部存在气隙缺陷,放电量严重超标,证明了定位分析的正确性,并对局部放电特征随施加电压的变化情况进行了分析。总结分析了各局部放电检测技术的优缺点,为GIS绝缘缺陷的诊断分析提供参考。

With the advancement of condition-based maintenance of electrical equipment,the live detection technol-ogy plays an increasingly important role in the state inspection of transmission and transformation equipment. Local-ization and analysis of a partial discharge（PD）defects in void of GIS solid insulation are introduced. First,the type ofdischarge is confirmed by UHF（ultra high frequency）PD detection method combined with the characteristics of PDspectrum. Then,the position of the defects is accurately located through channel signal reach time delay of the high-speed oscilloscope with consideration of the equipment structure. Finally,X-ray digital imaging detection and PDmeasurement are performed and find that there is a void inside the post insulator,and the PD is seriously exceeded,which proves the correctness of the location analysis. The characteristics of partial discharge with the change of volt-age are analyzed. In addition,the advantages and disadvantages of commonly used PD detection techniques are sum-marized and analyzed to provide reference for diagnosis and analysis of GIS insulation defects.