湿润污秽绝缘表面电场及针板电极下的沿面放电  

Electric Field of Wet Contamination on Dielectric Surface and Creeping Discharge in Needle-board Electrodes

作　　者：姚刚[1] 文习山[1] 蓝磊[1] 

机构地区：[1]武汉大学电气工程学院,武汉430072

出　　处：《高电压技术》2010年第6期1407-1414,共8页High Voltage Engineering

基　　金：国家重点基础研究发展计划(973计划)(2009CB724500)~~

摘　　要：为研究湿润污秽条件下绝缘表面电场分布和沿面放电特性,基于ANSYS软件建立了绝缘表面存在水膜和水滴的简化模型,用准静态谐分析法计算了湿润污秽对绝缘表面电场和沿面电位的影响。对针板电极下瓷和室温硫化硅橡胶的沿面放电进行了研究,对其影响因素展开分析。结果表明:以湿润污秽为中心的小区域电场发生畸变;瓷绝缘表面的污秽水膜影响绝缘子电压和电场分布,其电导率对绝缘子局部区域的电压分布具有影响。分离污秽水珠的个数、体积和电导率对室温硫化硅橡胶表面电场造成不同程度的影响,绝缘表面闪络过程存在阶段性。不同电场下的污秽水珠运动存在差异,不同绝缘表面沿面放电存在明显区别;电场极不均匀是导致针板电极下沿面放电存在极性效应的主要因素,湿润污秽的分布、体积和数量对极性效应均存在影响。In order to study electric field distribution and discharge characteristics along polluted dielectric surface under moist condition,a simplified model of insulation surface where water films and water droplets exist was established by the ANSYS software.The effects of moist pollution severity on electric field and potential distribution of dielectric surface were investigated based on quasi-static harmonic analysis.The creeping discharge of ceramic and RTV in needle-board and influential factors were studied.The results show that electric generates distortion around wet contamination region,filthy water film on the surface of porcelain insulator affects the voltage and electric field on insulator surface,and conductivity affects the voltage distribution on local area of porcelain insulator.The number,volume and conductivity of discrete pollution water drops all have suppressive effects on surface electric field of RTV.Significant stages exist during flashover along dielectric surface,there are differences among movements of filthy water droplets in different electric fields.Significant distinction exists between flashovers seperately along different insulation surface.Although non-uniform electric field is the main reason for the existence of polarity effect in flashover under needle-board electrodes,however,pollution grade,quantity and distribution pattern could also affect the results of polarity effect partly.

关 键 词：准静态场 绝缘表面 电导率 极性效应 污秽放电 电弧 

分 类 号：TM216[一般工业技术—材料科学与工程] TM853[电气工程—电工理论与新技术]