直流电压下SF6中自由线形导电微粒运动特性  

Motion Behavior of Free Conducting Wire-type Particles in SF6 Gas Under DC Voltage

作　　者：张乔根[1] 游浩洋 马径坦 秦逸帆 文韬[1] 郭璨[1] ZHANG Qiaogen, YOU Haoyang, MA Jingtan, QIN Yifan, WEN Tao, GUO Can(State Key Laboratory of Electrical Insulation and Power Equipment, Xi＇an Jiaotong University, Xi＇an 710049, Chin)

机构地区：[1]西安交通大学电力设备电气绝缘国家重点实验室

出　　处：《高电压技术》2018年第3期696-703,共8页High Voltage Engineering

基　　金：国家电网公司科技项目(SGSNKY00KJJS1501562)~~

摘　　要：在大量工程和实验中发现,相对于自由球形导电微粒而言,自由线形导电微粒对于设备绝缘性能威胁更大,且直流下微粒更容易进行起跳。为此利用搭建的自由微粒实验装置和观测平台,研究了直流电压下自由线形导电微粒在SF_6气体中的运动特性。结果表明：微粒起跳场强随气压无明显变化;随着微粒长度的增加,微粒起跳场强有略微增大的趋势;随着微粒直径的增大,微粒起跳场强呈现指数增长趋势;当微粒长度较短时,随着微粒直径的增加,微粒起跳场强实验值与计算值较为接近;当微粒长度〉3 mm时,随着微粒直径的减小,微粒起跳场强实验值与计算值相差较为明显。此外,还研究了线形微粒在SF_6气体中特有的两种现象：随着微粒长度增加、半径减小或气压降低,微粒产生飞萤现象和竖立现象的概率均增大,且上极板为正极性时更容易产生这两种现象。最后,文中从空间电荷角度对实验现象做出了解释。Based on a large number of engineering practices, free conducting wire-type particles threaten insulation of facilities more severely compared with sphere-type particles, and particles tend to lift off under a DC voltage. Therefore, we specially designed a free conducting particle experimental device and an observation system to study the motion behavior of free wire-type conducting particles in SF_6 gas. The results show that lift-off electric field strengths are unchangeable with gas pressure; when lengths of particles increase, lift-off electric fields strengths will increase slightly. When the radius of particles increases, lift-off electric field strengths will increase exponentially; when the length of particles is short, the experimental value and calculated value lift-off electric field will be similar as the radius of particles increase; when the length of particles is longer than 3 mm, the experimental value and calculated value are noticeably differential as the radius of particles decreases. Besides, special phenomena of wire-type particles in SF_6 are discussed, and it is found when the length increases, and the radius decreases or the gas pressure decreases, the appearance probability of ＂Firefly and Standing still＂ phenomenon will increase, and the phenomenon will easily appear on the negative electrode. Lastly, the experimental phenomenon is explained in the view of space charge.

关 键 词：直流电压 SF6 自由线形导电微粒 平板电极 起跳场强 飞萤现象 

分 类 号：TM595[电气工程—电器]