500kV线路瓷绝缘子雷击断串故障分析Fault Analysis for Lightning Strike-caused String Fracture of 500kV Line Porcelain Insulators
李岳,周路遥,李特,邵先军,初金良,高磊
LI Yue,ZHOU Luyao,LI Te,SHAO Xianjun,CHU Jinliang,GAO Lei
摘要(Abstract):
在机电负荷、污秽及环境温湿度等多重环境影响下,盘型悬式瓷绝缘子瓷件内微孔可能会逐渐扩展,直至开裂受潮,导致其机械强度和绝缘性能减弱,在遭受雷击或污闪时极有可能导致绝缘子炸裂、断串等恶性事故发生。针对一起500 k V线路瓷绝缘子雷击断串故障,结合雷电定位系统、线路分布式故障定位系统进行了线路耐雷水平分析。通过绝缘子试验,可判定故障原因为故障前已存在多片低零值绝缘子,当雷电绕击C相造成绝缘子串闪络后,大部分工频续流能量从低零值绝缘子头部瓷件内部放电通道泄放,产生的热量导致绝缘子炸裂脱开并引发断串。建议对线路低零值绝缘子进行排查,并合理采用疏导型防雷措施,对多雷区塔位优先安装线路避雷器。
Under multiple environmental impacts of electromechanical load, pollutants, ambient temperature and humidity, the micropores in cap and pin porcelain insulators may gradually expand or even crack and get damp, resulting in mechanical strength and insulation performance deterioration. When subjected to a lightning strike or pollution flashover, it is likely to cause vicious accidents such as explosion or insulator string fracture. In this paper, a lightning strike-caused fault of 500 k V line cap and pin porcelain insulators is introduced based on lightning positioning system, distributed line fault location system to analyze lightning resistance of the lines. It is concluded that there are several low(zero) resistance insulators in the string before the accident; after the insulator string flashover caused by a lightning strike on phase C, most of the power fre quency freewheeling current is discharged from the low(zero) value insulator in the porcelain discharge channel, and the heat generated causes the insulator explosion and string fracture. It is recommended to check the low(zero) value insulators and adopt leading-type lightning protection measures and install line arrester in intensive lightening areas.
关键词(KeyWords):
低零值绝缘子;雷击闪络;绕击;绝缘电阻;瓷件
low(zero) resistance insulators;lightning flashover;shielding-failure strike;insulation resistance;porcelain
基金项目(Foundation): 国网浙江省电力有限公司科技项目(5211DS190033)
作者(Author):
李岳,周路遥,李特,邵先军,初金良,高磊
LI Yue,ZHOU Luyao,LI Te,SHAO Xianjun,CHU Jinliang,GAO Lei
DOI: 10.19585/j.zjdl.202004003
参考文献(References):
- [1]邱志斌,阮江军,黄道春,等.输电线路悬式瓷绝缘子老化形式分析与试验研究[J].高电压技术,2016,42(4):1259-1267.
- [2]郭磊,张晓鹏,仝松利,等.低(零)值盘形悬式瓷绝缘子带电检测及实验研究[J].电瓷避雷器,2015(4):14-18.
- [3]张也,彭子健,付强,等.环境湿度对瓷质绝缘子串电压分布及红外热像检测的影响分析[J].电网技术,2 018,42(4):1342-1349.
- [4]范强,罗浩,曲锴,等.500 kV输电线路低零值绝缘子对绝缘子串电压分布的影响[J].绝缘材料,2018,51(12):74-78.
- [5]蒋兴良,夏强峰,胡琴,等.劣化绝缘子对悬垂串电场分布特性的影响[J].中国电机工程学报,2010,30(16):118-124.
- [6]付炜平,王伟,董俊虎,等.利用红外热像技术检测劣化绝缘子的适用性分析研究[J].高压电器,2018,54(2):110-114.
- [7]输电线路分布式故障诊断系统:GB/T 35721-2017[S].北京:中国标准出版社,2017.
- [8]王剑,谷山强,赵淳,等.计及工作电压时同塔双回输电线路雷击闪络特性[J].高电压技术,2014,40(9):2923-2930.
- [9]杜林,陈寰,陈少卿,等.架空输电线路雷电绕击与反击的识别[J].高电压技术,2014,40(9):2885-2893.
- [10]交流电气装置的过电压保护和绝缘配合设计规范:GB/T50064-2014[S].北京:中国计划出版社,2014.
- [11]标称电压高于1 000 V架空线路绝缘子串工频电弧试验:DL/T 812-2002[S].北京:中国电力出版社,2002.
- [12]劣化悬式绝缘子检测规程:DL/T 626-2015[S].北京:中国电力出版社,2015.
- [13]交流架空输电线路用绝缘子使用导则第1部分:瓷、玻璃绝缘子:Q/GDW 515.1-2010[S].北京:中国电力出版社,2010.
- [14]李国宝.输电线路雷电灾害防御体系建设研究与应用[J].山西电力,2019(4):22-25.
- [15]王锐,彭向阳,梁永纯.一起因雷击造成的220 kV架空地线断线故障分析[J].广东电力,2019,32(4):106-111.
- [16]朱迪锋,黄建峰,张湘红,等.500 kV线路架空地线断落原因分析及快速修复方法[J].内蒙古电力技术,2018,36(2):47-49.
- 低零值绝缘子
- 雷击闪络
- 绕击
- 绝缘电阻
- 瓷件
low(zero) resistance insulators - lightning flashover
- shielding-failure strike
- insulation resistance
- porcelain