一起35 kV电缆中间接头故障分析及对策研究

Analysis and Preventive Measures for 35 kV Cable Intermediate Joint Fault

针对一起近期发生的35 kV电缆中间接头击穿故障,进行了故障接头解体检查和故障原因分析,指出了电缆中间接头压接管施工工艺存在严重缺陷,导致了压接管、电缆主绝缘及预制式接头之间存在台阶气隙,以及局部场强高度集中引起局部放电,最终导致中间接头绝缘击穿,提出了因施工工艺不当导致电缆接头故障的防范措施。

Aiming at the breakdown of the 35 kV cable intermediate joint that occurred recently,the disassembly inspection of the faulty joint and the cause analysis of the fault were performed.The serious defects were found in the construction process of the intermediate joint pressure pipe,resulting in a step between the crimping pipe,the main insulation of the cable and the prefabricated joint.Air gaps,which led to high local concentration of partial field intensity and partial discharge,and eventually insulation breakdown of the intermediate joints.The preventive measures for cable joint failure due to improper construction process were proposed.