摘要
套管故障是导致变压器非计划停运的重要原因之一。目前主要依靠传统预防性试验方法来评估套管的绝缘状态,但预试周期长,难以及时发现运行中套管的潜在故障。为此,提出了基于特高频信号的套管局部放电带电检测与时间差定位方法。首先阐明了特高频定位方法的基本原理,然后在实验室建立套管局部放电特高频检测试验平台,通过试验对这种方法进行了检验。试验结果表明:1)套管顶部的接触不良放电和末屏引线接触不良放电的信号波形振荡上升时间短,时间差测量和定位计算结果准确、分散性小;2)发生在油箱内部的下截套管沿面放电和均压罩悬浮放电的信号波形振荡上升时间长,时间差分散性大,定位结果位于套管上瓷套底部,分散性大。该研究对于推动套管局部放电的带电检测和定位技术的应用与发展具有重要指导意义。
It is bushing faults that cause most of transformer unplanned outages. Until now, preventive test methods are widely used for estimating the insulation condition of bushings. Since the preventive test cycle is too long, it is difficult to find out latent defects effectively. In this paper, on-line partial discharge （PD） detection method and a TDOA location method based on ultra-high frequency （UHF） signals are presented. Firstly, the fundamental of UHF location method is demonstrated; then, experiments are carried out to verify this method. Test results show that： （1） in the tests of poor connection in bushing tap and suspended discharge on bushing＇s top cap, the rise time of UHF signals is short with small dispersions, which shows accurate location results; （2） in the tests of surface discharge and floating discharge lying on the bottom of bushing, both of the rise time and last time of UHF signals is longer with bigger dispersions, and the location results are both focused around the bottom of the upper porcelain insulator. The research result is valuable and meaningful for on-line PD detection and location for bushings.
出处
《电网技术》
EI
CSCD
北大核心
2015年第6期1719-1724,共6页
Power System Technology
基金
广州供电局有限公司科技项目(K-GZM2013-010)的资助
关键词
套管
局部放电
定位
特高频
bushing
partial discharge
location
ultra-high-frequency
