摘要
笔者结合超声波在线监测、放电电压值和SF6分解产物测量等多种手段,定位和分析了某变电站550 kV GIS现场交流耐压试验下的4处放电故障,总结研究了这几次放电故障,讨论了盆式绝缘子沿面闪络的主要原因,探讨了沿面闪络与缺陷局部放电、表面电荷输运之间的关系,认为盆式绝缘子表面金属颗粒易于起始负电晕放电,积聚负表面电荷,进一步畸变表面电场,提供放电通道发展所需的电荷;同时当盆式绝缘子与电极接触不良时,认为此时沿面放电易于起始于三结合点处的介质阻挡电晕放电,该放电的发展与带电粒子的迁移扩散运动是形成沿面放电的前提条件。最后提出了GIS超声波故障定位与分析以及相关实验与理论研究的几点建议。
By combing the ultrasonic online monitoring and the measurement of discharge voltage value and SF6 decomposition products, four discharge failures in 550 kV GIS during withstanding AC voltage field test are located and analyzed. The main causes of the flashover on cone-type spacer surface are discussed. The relationship among surface flashover, partial discharge of defects, and surface charge transport are investigated. It is concluded that：l）the metal particles on the surface of conevtype spacer tend to initiate negative corona and accumulate negative surface charge,thus to intensify the distortion of the surface electric field and supply the required charge for discharge channel propagation; and 2）when the contacts between cone-type spacer and electrodes is insufficient, the surface discharge originates from the dielectric barrier corona at triple-junction points, while the corona propagation and the charged particles＇drift and diffusion movement become the precondition to generate surface discharge. In addition, some suggestions are offered, concerning GIS field assemblage, ultrasonic location of failure, and the related experimental and theoretical researches.
出处
《高压电器》
CAS
CSCD
北大核心
2014年第11期30-37,共8页
High Voltage Apparatus
基金
国网浙江省电力公司科技项目(ZDK012-2011)~~
关键词
GIS
现场交流耐压试验
故障定位
沿面闪络
局部放电
表面电荷
GIS
field withstanding AC voltage test
failure location
surface flashover
partial discharge
surface charge
