10kVT型电缆接头受潮缺陷的电场监测方法研究

Research on Electric Field Monitoring Method of 10 kV T-Type Cable Joint Under Wet

为获得有效的T型电缆终端接头劣化缺陷在线监测方法,首先仿真分析了T型电缆接头在典型气隙受潮缺陷下的电场分布特性,提出了基于电场信号变化的缺陷监测识别方法;搭建了试验平台,以现场实际案例为对象,开展了受潮条件下T型电缆终端接头电场信号监测试验,对所提方法进行了验证。研究结果表明,对于劣化的T型电缆终端接头,当湿润足够充分时,空间电场有效值增幅达200%;而当内部受潮导致局部放电时,空间电场有效值增幅可达5~6倍。通过对比监测位置空间电场强度的上升速率,可以识别T型电缆接头是否出现劣化迹象。

In order to obtain an effective online monitoring method for T-shaped cable terminal joints deterioration,this paper firstly simulates and analyzes the electric field distribution characteristics of T-type cable joints under typical air gap moisture defects,and proposes a defect monitoring and identification method based on changes in electric field signals.Then the electric field signal monitoring test of the lower T-type cable terminal joint is carried out to verify the proposed method.Research results show that,for the deteriorated T-type cable terminal joint,when the humidity is sufficient,the effective value of the space electric field increases by 200%;and when the internal moisture causes partial discharge,the effective value of the space electric field increases by 5~6 times.By comparing the rising rate of the electric field intensity in the monitoring location,it can identify whether the T-shaped cable joint has signs of deterioration.