高压电缆接地回路电阻带电检测及消缺应用

Application of Resistance Detection and Loss Elimination in Ground Circuit of High Voltage Cable

因铅封开裂、进水氧化等接地系统缺陷是导致电缆接头本体故障的主要原因之一,尤其在杭州地区多发地质沉降、地下水位高的环境下,高压电缆接地系统不良隐患尤为突出。传统的金属护层感应电流带电检测、回路电阻停电检测等测试方法受到停电周期、接地箱接线方式等因素限制,仍存在盲区。近年来,杭州公司引入接地回路电阻带电检测手段,在带电情况下对接地系统回路电阻进行测试,通过超3 600处现场测试,在传统带电检测手段均显示正常的情况下,发现并消除接地系统隐患缺陷超30处,有效提升了杭州主网电缆接地系统健康水平。

Grounding system defects such as lead seal cracking and water inlet oxidation are one of the main causes of cable joint failures,especially in the environment of frequent geological settlement and high groundwater level in Hangzhou,potential hazards of the poor grounding system of high voltage cables are particularly prominent.The traditional testing methods,such as the charging detection of sheath circulation and the circuit resistance outage detection,are limited by the blackout period and the wiring mode of the grounding box,and there are still blind areas.In recent years,State Grid Hangzhou power supply company introduced the grounding circuit resistance live detection method,in the case of live grounding system circuit resistance test,through more than 3 600 field tests,in the case of traditional live detection methods were showed to be normal,found and eliminated hidden defects more than 30 of the grounding system,effectively improving the health of Hangzhou main network cable grounding system.