长空气间隙放电特性研究综述

Summary of Research on Flashover Characteristics of Long Air-gaps

为获得长空气间隙在不同间隙距离、不同电压类型、不同电极结构下的放电规律,介绍了国内外长空气间隙放电特性研究的代表性成果,分析了棒-板和棒-棒间隙在不同间隙距离、不同冲击电压波前时间下的放电特性,给出了典型的放电特性曲线。对美国、日本和中国开展的输变电杆塔间隙试验结果进行了分析,介绍了线路和变电站相-地和导线相间空气间隙试验结果,对比了不同塔型结构条件和波形条件的影响。研究表明随间隙距离的增大,棒板间隙临界放电电压对应的波前时间逐渐增大;塔宽对杆塔间隙操作冲击下的放电电压有明显的影响;随着操作冲击电压的升高,海拔对操作冲击放电电压降低的作用减小。该综述是对目前国际上典型间隙和输变电间隙放电特性研究成果的总体分析,可为绝缘设计提供依据。

In order to obtain the flashover discipline of long air-gap under different gap distances,we described different types of voltages,different electrode structures,and the representative research results of long air-gaps flashover characteristics,analyzed the flashover characteristics of typical rod-plane and rod-rod gaps with different gap lengths and different wave-front times,and presented some typical gap flashover characteristics curves.Moreover,we analyzed the tower clearance test results of transmission transaction tower clearance from United States,Japan,and China,and compared the impact of different tower structural conditions and test wave conditions.The research results show that the wave-front of critical flashover voltage rises with the distance,and the switching impulse voltage is influenced remarkably by the tower width.The influence of altitude on the switching impulse flashover voltage gets weaker with increasing of switching impulse voltage.In general,current international research results on typical electrode air-gaps and transmission transaction air-gaps flashover characteristics are analyzed,which provide a basis for external insulation designs.