雨凇覆冰对输电线路分裂导线起晕电压的影响  

Influence of Glaze Icing on Corona Inception Voltage of Bundle Conductor for Transmission Lines

作　　者：陈吉[1] 蒋兴良[1] 舒立春[1] 胡建林[1] 张满[1] 李源军[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2期395-404,共10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：雨凇覆冰后的输电线路导线表面电场会发生畸变从而降低起晕电压值,但目前国内外尚未深入分析雨凇覆冰对导线电晕特性的影响规律,且缩比导线模型所得结论与工程实际存在较大差异。为探求雨凇覆冰导线的电晕特性,在人工气候实验室内完成了3种分裂导线雨凇覆冰后的交流电晕试验,结合紫外成像与拟合法对导线雨凇覆冰后的电晕特性进行了测量,建立了有限元模型并分析了导线表面电场强度以弥补雨凇电晕研究的空缺。结果表明:雨凇覆冰会降低裸导线起晕电压值约50%;导线表面的起晕电压会在最初的15 min内下降较快,之后会随着雨凇覆冰程度的增加而继续下降,但其速度逐渐饱和;相同雨凇覆冰时间内分裂子导线越多则起晕电压值越高;覆冰水电导率的大小并不会直接改变或影响雨凇覆冰表面形态,但起晕电压值却会随着覆冰水电导率的增加而持续降低。所得结论可供雨凇覆冰地区架空输电线路的设计和选型参考。On the surface of a naked power line conductor with glaze icing, icicles would distort electric field and hence decrease the corona onset voltage of conductors. However, there is no in-depth analysis of how glaze icing influences co- rona onset voltage of power line conductors. Since using the scaled conductor model to study actual bundle conductor would result in significant difference from engineering practice, we conducted a series of AC corona tests using single-, double- and triple-bundle conductors with glaze icing the glaze in artificial climate laboratory, and used UV imaging technology and I-U curve fitting to measure and analyze the corona inception voltage of the tested conductors. Combining with the glaze icing morphology, we also established an icing branches＇ electrical field model to research coronas on glaze iced bundle conductors, which could complement the researches about glaze corona. The results show that glaze icing can reduce the inception voltage by about 50%, while the corona onset voltage decreases continually with increasing icing time with a speed that is high in the first 15 minutes of icing but gradually decreases until gets saturated. In the same icing time, a conductor with more sub-conductors has higher onset voltage than others. Glaze icing morphology dose not vary with different freezing-water conductivity, but the increase of freezing-water conductivity will gradually decrease con- ductor corona starting voltage. The conclusions can be referred by designing and selection of overhead transmission lines in glaze areas.

关 键 词：输电线路 分裂导线 雨凇覆冰 交流电晕试验 起晕电压 覆冰水电导率 紫外成像 

分 类 号：TM752.5[电气工程—电力系统及自动化]