500kV超高压输电线路架空地线频繁断股原因分析  

Cause Analysis of Frequent Broken Strands of Overhead Ground Wire on 500kV Transmission Line

作　　者：张涛[1] 高云鹏[1] 田峰[1] 王海学[1] 陈浩[1] 谢利明[1] 张雪超 ZHANG Tao;GAO Yunpeng;TIAN Feng;WANG Haixue;CHEN Hao;XIE Liming;ZHANG Xuechao(Inner Mongolia Power Research Institute, Hohhot 010020, China)

机构地区：[1]内蒙古电力科学研究院,呼和浩特010020

出　　处：《内蒙古电力技术》2019年第1期11-15,共5页Inner Mongolia Electric Power

基　　金：内蒙古电力(集团)有限责任公司2018年科技计划项目(2018-36)

摘　　要：某500kV超高压输电线路架空地线频繁断股,采用宏观形貌检查、断口SEM检测、显微组织检测、力学性能检测及镀锌层质量检测等方法,对架空地线断股原因进行分析。结果表明:架空地线采用的镀锌钢线材料中存在超标脱碳层、非金属夹杂物及网带状铁素体等冶金及热加工缺陷,造成钢线的强度和韧性均不合格;同时,在钢线表面存在裂纹及尖锐凹坑等缺陷,在大风等恶劣气象条件下的拉应力载荷作用下,钢线表面沿裂纹及尖锐凹坑等应力集中部位发生脆性断裂。A comprehensive analysis based on macro-structure inspection, fracture morphology observation, metallurgical structure, mechanical properties and zinc coat test of overhead ground wire was made on broken strands damage of 500kV UHV transmission line. The results showed that the quality of galvanized steel wire was destoried. The non-metallic inclusions, decarburized layer and mesh belt ferrite of galvanized steel wire were serious which led to the inferior strength and ductility. Meantime, there were many cracks and sharp pits on surface of galvanized steel wire. When the abnormal load of atrocious weather was used to the overhead ground wire, it was easy to fracture for galvanized steel wires because of the huge stress concentration on cracks and sharp pits.

关 键 词：架空地线 断股 夹杂物 脱碳层 裂纹 镀锌层 

分 类 号：TM755[电气工程—电力系统及自动化]