摘要
GIS局部放电特高频UHF在线检测得到了广泛的实际应用,但对GIS绝缘子的闪络故障还缺少有效的预警能力,由此引起了对UHF检测方法灵敏度的极大关注。文中对一个实际GIS支撑绝缘子的实际局部放电进行了实验研究,结果表明,局部放电UHF检测方法确实存在灵敏度的死角。该支撑绝缘子的局部放电的脉冲电流陡度在很大的范围内变化,所产生的电磁波的频带也在很大范围内变化,但大部分局部放电的电磁波频率低于UHF频段,不能够被UHF检测方法有效检测。由此推断,在局部放电UHF检测中,严重的局部放电未必表现为高脉冲幅值和高脉冲频度,有可能被现有的诊断机制所忽略。
UHF detection of partial discharges（PD）in GIS has been widely used,however its capability of pre-warn-ing the flashover failures of the GIS insulators is limited,causing a big concern on the sensitivity of the UHF method.Experimental investigation is made in this paper on the PDs in an actual GIS supporting insulator with actual defect,which demonstrates that the UHF method does have blind angle in sensitivity. The PD pulses of the supporting insula-tor change greatly in there steepness,causing great change of the frequency band of the RF signals from the PDs.Most of the PDs have RF signals lower than UHF band,and cannot be detected by UHF method. It means that seri-ous PDs of the GIS insulator could possibly show UHF pulses of small amplitude and small density,and easily be ne-glected according to the current diagnosing criteria.
作者
李晓
徐洋
王勇
李星
熊俊
刘卫东
LI Xiao1, XU Yang2, WANG Yong1, LI Xing2, XIONG Jun1, LIU Weidong2(1. Guangzhou Power Supply Bureau Test ＆ Research Institute, Guangzhou 510410, China; 2. State Key Lab. of Power System, Dept. of Electrical Engineering, Tsinghua University, Beijing 100084, Chin)
出处
《高压电器》
CAS
CSCD
北大核心
2018年第5期63-67,73,共6页
High Voltage Apparatus
基金
中国南方电网有限责任公司科技项目(GZM2015-2-0006)~~
关键词
GIS
绝缘子
局部放电
UHF检测方法
脉冲电流法
GIS
insulator
partial discharge （PD）
ultra-high frequency （UHF） method
pulse current
作者简介
李晓（1989-），女，工程师，工学硕士，主要从事电气试验技术方面工作。
