一则110kV电缆GIS终端的局放带电检测与定位案例（2）

针对110kV电缆线路局放带电普测时发现的一个疑似局放信号，复测时确认到该信号是来自GIS电缆终端。在GIS电缆终端的脉冲电流法定位测试时曾推定该局放是在电缆终端绝缘套管顶部或与GIS导管的连接部近旁，为了缩小局放定位的范围，也采用了特高频UHF传感器和接触型超声波AE传感器在脉冲电流传感器所定位位置范围内的GIS盘式绝缘子及其附近进行了局放精确定位。因在该位置范围内UHF和AE均没有检测到该局放信号，故曾根据极为类似的成功定位案例经验暂时推定该局放源较有能位于靠近电缆终端顶部的附近。为了进一步确定局放源的具体位置，又采用倒送电配合GIS开关切换隔离的“分区带电”排除法对该局放的发生位置进行排查，结果证实该局放信号来自GIS上部的PT部分。本论文主要介绍利用三个GIS终端所同时检测到的局放信号配合部分带电排除法的开关操作所进行的局放定位过程。

A Case Study of A PD Detection and Localization at 110kV Cable GIS Termination (2)

A PD was detected from a cable GIS termination during a periodical PDM inspection for 110kV cable circuit. In further confirmation measurement the PD was found at the other cable GIS termination connected to the same buses, in the next PD was located as around the joint of cable termination top and GIS conductor. To localize the PD point exactly several kinds of PD sensors like HFCT, UHF, AE, TEV were used with different combination patterns. It is shown that the PD point should be close to the termination because UHF and AE could detected any PD signals at the nearest GIS spacer. Then a so-called isolated detection method is used in that PD location is put in a particular area in energization by GIS disconnect switch, and the PD was located at a PT on top of the GIS. This paper mainly describes the PD location process.