新型的电缆局部放电在线监测系统研究

Research on a New Online Monitoring System for Partial Discharge of Cables

城市电网中因电缆沟电缆故障起火的事件时有发生,电缆绝缘劣化是电缆发生故障的重要原因,局部放电(简称局放)是电缆绝缘缺陷的表征,也是导致其绝缘劣化的主要原因之一。一直以来手持局放仪巡检电缆线路是诊断电缆绝缘状态的重要方法,为降低工作人员手持局放仪巡线的繁琐程度,研究了一种新型的电缆局放在线监测系统,该系统中使用高频电流传感器耦合流过电缆接头接地引下线的高频脉冲电流信号,并通过新型局部放电采集器将局放综合信息上传至局放监测主机,完成局放信号的实时在线监测。与传统的局放采集器相比新型局放采集器搭载了电力人工智能芯片,实现了局放信号处理的边缘计算,极大地缓解了庞大安装数量级下局放监测主机的压力,最后在现场测试中应用了该系统,并验证了该系统的可行性。

In the urban power grid,cable channel are fired frequently due to cable faults.Deterioration of cable insulation is an important cause of cable failure.Partial discharge is a symptom of cable insulation defects and one of the main causes of insulation degradation.It has always been an important method to diagnose the cable insulation state by hand-held partial discharge instrument patrolling cable line.In order to avoid the tediousness of the staff holding the partial discharge instrument to patrol the line,a new type of cable partial discharge online monitoring system was introduced in this paper.In this system,a high frequency current sensor was used to couple the high-frequency pulse current signals passing through the ground wire of the cable joint,and the partial discharge comprehensive information is uploaded to the partial discharge monitoring host-machine through a new partial discharge collector to complete the real-time online of the partial discharge signal monitoring.Compared with the traditional partial discharge collector,the new partial discharge collector was equipped with an electric artificial intelligence chip,which realizes the edge calculation of partial discharge signal processing and greatly alleviate the pressure of the local discharge monitoring host-machine under the huge installations.Finally,the system was applied in the field test to verify the feasibility of the system.