一起220 kV交联聚乙烯电缆中间接头击穿故障原因分析及措施  

Cause Analysis and Measures of a 220 kV XLPE Cable Intermediate Joint Breakdown Fault

作　　者：郑必成 顾蔚泉 ZHENG Bicheng;GU Weiquan(Fujian Fuqing Nuclear Power Co.,Ltd.,Fuqing 350318,China)

机构地区：[1]福建福清核电有限公司,福建福清350318

出　　处：《电工技术》2021年第9期99-100,154,共3页Electric Engineering

摘　　要：针对某核电厂一起220 kV交联聚乙烯电缆中间接头击穿故障,对击穿的部位进行解剖和分析后,指出电缆中间接头制作过程中,金属铜护套与电缆铝波纹护套对接的锡焊施工工艺存在缺陷,未使用铜编织带连接,锡焊部位的机械强度较薄弱,在电缆运行中出现开裂现象,在开裂部位两端形成电位差,持续的放电损伤了电缆半导体屏蔽层,最终导致电缆主绝缘击穿。最后,针对电缆中间接头制作施工工艺的不足提出了改进措施。For a breakdown fault of 220 kV XLPE cable intermediate joint in a nuclear power plant,the breakdown part is dissected and analyzed.It is pointed out that there are defects in the tin welding process of the butt joint between the metal copper sheath and the aluminum corrugated sheath of the cable in the production process of the cable intermediate joint.The copper braided tape is not used for connection,the mechanical strength of the tin welding part is weak,and the cracking phenomenon occurs in the operation of the cable.A potential difference is formed at both ends of the cracked part,and the continuous discharge damages the cable′s semiconductor shielding layer,and eventually leads to the breakdown of the cable′s main insulation.Finally,improvement measures are proposed for the insufficiency of the construction technology of the cable intermediate joint.

关 键 词：中间接头 金属屏蔽层 锡焊 悬浮电位 绝缘击穿 

分 类 号：TM757[电气工程—电力系统及自动化]