雾凇覆冰对铝管起晕电压的影响  

Influences of Rime Icing on Corona Inception Voltage of Smooth Conductor

作　　者：陈吉[1] 蒋兴良[1] 舒立春[1] 张志劲[1] 谢彦斌[1] 张满[1] 

机构地区：[1]重庆大学输配电装备及系统安全与新技术国家重点实验室,重庆400030

出　　处：《高电压技术》2014年第5期1351-1357,共7页High Voltage Engineering

基　　金：国家重点基础研究发展计划(973计划)(2009CB724502;2009CB724501)~~

摘　　要：雾凇属于干增长覆冰,会在导线表面产生凹凸不平的冰树枝,因此会畸变导线表面的电场分布。为探求雾凇覆冰导线起晕电压值变化规律,利用低温低气压人工气候实验室对雾凇覆冰的光滑铝管进行了交流电晕的试验。试验中,利用紫外成像仪对覆冰导线的放电光子数进行测量,并基于光子数变化获得起晕电压值。同时,利用有限元法仿真计算覆冰导线的最大场强以验证试验的正确性。结果表明:雾凇对导线起晕电压的影响主要是由于冰树枝尖端对电场的畸变作用,从而降低导线的起晕电压值;覆冰后的导线起晕电压值会随着雾凇覆冰厚度的增加而上升,但上升会变慢;冰水电导率不同对雾凇形貌和覆冰导线的起晕电压值没有影响;根据起晕电压修正公式,可快速计算出雾凇覆冰后的导线起晕电压值。所获结论可供覆冰导线起晕电压的进一步研究参考。Rime which is categorized as dry icing would cause uneven ice tree growth on conductor surface, and consequently distort the electric field nearby conductor surface. To obtain the influence of rime on the corona inception voltage of conductors, we carried out AC corona tests of rime-covered aluminum in artificial climate chamber which had low temperature and low pressure. In the tests, we measured photon numbers using UV camera, and hence obtained corona inception voltage of the iced conductor according to the relationship between corona and photon number. We also calculated the maximum field strength of the iced conductor using the finite element method to verify the obtained test results. It is concluded that the influence of rime on corona inception voltage is mainly due to distortion of electric field caused by the tips of ice tree, which may also decrease the conductor＇s corona onset voltage. The corona onset voltage increases with rime ice thickness at a speed of slowing-down until becoming to be saturated. Rime morphology and the corona inception voltage do not vary with freezing-water conductivity. Plus we can calculate the corona onset voltage of rime-ice-covered conductor using a correction formula. These results provide a basis for further studies of the corona inception of conductors after rime icing.

关 键 词：光滑铝管 雾凇覆冰 起晕电压 电导率 紫外成像 有限元 

分 类 号：TM852[电气工程—高电压与绝缘技术]