直流气体绝缘线路中自由金属微粒的局部放电特性与影响因素

发布时间：2018-02-02 16:58

本文关键词： 直流GIL 同轴圆柱电极线形微粒局部放电信号运动特性飞萤现象　出处：《高电压技术》2017年02期 　论文类型：期刊论文

【摘要】：直流气体绝缘线路(GIL)中的自由金属微粒会使电场发生畸变,使绝缘气体/绝缘子发生局部放电等劣化效应。为此,研究了微粒局部放电的影响因素以及严重程度,在密封同轴圆柱腔体内充入不同气压的SF6气体,以不同长度的线形微粒进行了试验,利用脉冲电流法及高速相机同时观察了其局部放电信号与微粒运动行为,对局部放电信号的平均局部放电量、平均局部放电时间间隔进行了分析。结果表明:对于自由线形金属微粒,微粒的平均局部放电量与长度、最大可能带电量成正相关,可根据微粒的局部放电信号判断其危险程度及微粒长度;在负电压下,微粒跳起运动至高压电极附近,发生"飞萤"现象;在正电压下,微粒在外壳地电极跳起后落至地电极,并不断弹跳;且微粒在负电压下的平均局部放电量是在正电压下的2~5倍,平均局部放电时间间隔较小;随着气压增大,气体的平均局部放电量随之减小,但有趋于饱和的趋势。因此,自由金属微粒的局部放电特性可以为金属微粒的严重程度判别与故障诊断提供依据。
[Abstract]:The free metal particles in DC gas insulated line (Gil) will make the electric field distorted and the insulation gas / insulator cause partial discharge degradation effect. The influence factors and severity of particle partial discharge were studied. The SF6 gas with different pressure was filled into the sealed coaxial cylinder cavity, and the experiment was carried out with linear particles of different lengths. The pulse current method and high speed camera were used to observe the PD signal and particle motion simultaneously, and the average partial discharge (PD) of the PD signal was obtained. The average partial discharge time interval is analyzed. The results show that the average partial discharge amount of the particle is positively correlated with the length of the free linear metal particle and the maximum possible charge is positive. The danger degree and particle length can be judged according to the partial discharge signal of the particle. Under the negative voltage, the particles jump up and move to the vicinity of the high voltage electrode, and the phenomenon of "fireflies" occurs. At positive voltage, the particles jump up and fall to the ground electrode, and bounce continuously; The average partial discharge of particles at negative voltage is 2 ~ 5 times of that at positive voltage, and the average partial discharge time interval is smaller. With the increase of gas pressure, the average partial discharge of gas decreases, but tends to saturation. The partial discharge characteristics of free metal particles can be used to judge the severity and fault diagnosis of metal particles.
【作者单位】：华北电力大学高电压与电磁兼容北京市重点实验室;
【基金】：国家重点基础研究发展计划(973计划)(2014CB239502)~~
【分类号】：TM75
【正文快照】： Characteristics of Partial Discharges Caused by Free Metal Particle and InfluencingFactors in DC Gas Insulated LineLI Qingmin,LIU Sihua,WANG Jian,WANG Zhiyuan(Beijing Key Laboratory of High VoltageElectromagnetic Compatibility,North China Electric Power

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