电工技术学报2024,Vol.39Issue(19):6175-6186,12.DOI:10.19595/j.cnki.1000-6753.tces.231253
高海拔正极性操作冲击下球-板间隙流注起始发展特性
Initiation and Development Characteristics of Streamer Discharge of Sphere-Plane Gaps under Positive Switching Impulse in High Altitude Area
摘要
Abstract
The valve hall in converter station,as an important part of China's extra-high voltage(EHV)and ultra-high voltage(UHV)project in high-altitude areas,has a large number of sphere-plane configurations inside.The study of sphere-plane gap discharge mechanism in high-altitude areas has practical engineering significance for the design of external insulation of EHV and UHV projects. In this paper,the switching impulse test of sphere-plane gaps with different sizes of sphere electrodes at gap distance of 1.0~3.0 m is carried out in Kunming area(altitude of 2 100 m).The discharge voltage,discharge current and optical images of different working conditions are collected by the high potential current acquisition device and the high speed camera.The discharge process,the dispersion of streamer initiation,streamer branch development characteristics,and the changing rules of the injected charge under different electrode structures and gap distances are analyzed.And the effects of the voltage rise rate on the streamer discharge parameters are also analyzed.On this basis,some of the initial parameters of the streamer are compared with those of the low altitude test,and the effect of altitude on the initial characteristics of the streamer is studied. The results show that the discharge process will be shortened with the increased altitude and reduced air pressure under the same working conditions.When the gap distance is 2.0 m and 3.0 m respectively,and the sphere diameter increases from 0.3 m to 0.9 m,the maximum increment of streamer inception time is 54.8%and 57.0%respectively,and its dispersion also increases.With the increasing gap distance,the streamer incepion time will be earlier.The streamer inception voltage increases with the increase of sphere electrode diameter and gap,and the influence of sphere electrode diameter on streamer inception voltage is more obvious.The injected charge of the streamer increase with the increasing gap distance and sphere diameter,which ranges from 1.1 μC to 15.6 μC.With the increase of sphere electrode diameter,the initial streamer length also increases obviously,but the gap length has little effect on the initial streamer length.During the process of initial streamer into final jump,the average development velocity of the main channel and sub-channel of the streamer branch ranges from 1.2~5.0 cm/μs and 0.8~2.6 cm/μs,respectively.At this stage,new branches may develop on the main channel and sub-channel,but the development speed is relatively stable.In the final jump,the main channel of the streamer branch develops rapidly until the breakdown,with an average development rate of about 10~25 cm/μs,and the sub-channel stops developing and then extinguishes.The streamer inception time and its dispersion decrease with the increasing applied voltage rise rate,and the injected charge increases with the increasing of streamer inception voltage and the voltage rise rate.It can be concluded that the voltage rise rate has obvious influence on the injected charge.关键词
高海拔/球-板间隙/流注起始/注入电荷/电压上升率Key words
High altitude/sphere-plane gaps/streamer inception/injected charge/voltage rise rate分类
信息技术与安全科学引用本文复制引用
方雅琪,毛苏涵,杨炳森,高嘉辰,张晓星..高海拔正极性操作冲击下球-板间隙流注起始发展特性[J].电工技术学报,2024,39(19):6175-6186,12.基金项目
国家自然科学基金(52107146)和特高压电力技术与新型电工装备基础国家工程研究中心开放基金(NELUHV-2021-KF-01)资助项目. (52107146)