Analysis on the surface arc characteristics of natural snow covered post insulator
Post insulator is one of the most important insulation equipment in substation.After long-term operation in natural environment,the surface of the substation insulator is usually covered by pollution.Most parts of northern China have snow in winter,and the snow will have a significant impact on the external insulation performance of post insulator.The reason is that part of the surface contamination of the insulator is dissolved in the snow,which produce a conductive solution.Subsequently,the electric field distribution is changed and the surface leakage current is generated.Under certain conditions,the surface snow even leading to surface flashover.This phenomenon is particularly significant in snowmelt which is also the most prone to surface discharge.There have been reports of surface flashover accidents of station bushing in the snow.In this paper,the surface snow cover of the specimen insulator is analyzed after a natural snowfall.Then,the flashover test of 110kV AC post insulators with natural snow cover is carried out.And surface arc was captured by a high-speed digital camera during the voltage test.The test results indicated that the flashover characteristics of snow covered post insulator is different from fog flashover.The path of arc development is concentrated on the side of snow cover,and the presence of snow had no effect on the development of the arc.The arc firstly generated on the contamination surface beneath the snow layer,then gradually drift to the outside air above the snow layer,and part of the snow cover was knocking-out.The mechanism of snow flashover of insulator is worth further study.This work can provide technical reference for substation to prevent external insulation accidents in extreme weather conditions.
post insulator snow flashover surface arc artificial pollution test
Junyi Hu Meijiang Gui Chuyan Zhang Jianchao Li Liming Wang
School of Information Engineering China University of Geosciences(Beijing)Beijing,China Graduate School at Shenzhen Tsinghua University Shenzhen,China
国际会议
重庆
英文
1-4
2017-09-25（万方平台首次上网日期，不代表论文的发表时间）