均匀电场作用下绝缘材料表面流注发展研究综述

Overview of Streamer Propagation Along Insulation Surfaces in the Uniform Field

绝缘子沿面闪络是输电线路设计和运行中面临的重要问题。流注的产生和发展是绝缘发生先导和闪络前的重要阶段,研究绝缘材料表面流注产生和传播对输电线路绝缘的设计和优化有很重要的意义。绝缘材料流注发展研究采用的实验装置是"三电极"结构,两个极板平行放置用以产生均匀电场,绝缘材料垂直放置在两极板之间,与下极板绝缘的针尖通以脉冲电压产生流注放电,均匀电场中流注的发展很少分叉,可以忽略空间电荷的影响。基于此,综述了绝缘材料表面流注发展的研究现状,介绍了绝缘材料性能、材料外形、外加电场、外加脉冲电压幅值等因素对绝缘表面流注发展的影响,总结了近年来绝缘材料表面流注发展所取得的成果,也提出了研究中尚不能合理解释的现象以及有待深入研究的问题。

The flashover of insulators is one of important problems in the design and operation of transmission lines.The comprehensive study of the interaction of a material surface with the streamer development process is of major importance where the improvement of the indoor and outdoor insulation performance is concerned.Streamer propagation is studied in three groups of tests.A uniform field arrangement consists of two parallel plane electrodes in air between which insulators are inserted perpendicularly to the electrodes.Streamers are initiated from a sharp point which is set in a shaped receptacle at the center of the lower grounded plane.In a uniform field arrangement,significant space charge effects due to streamer branching can be avoided.We summarize the research status of streamer propagation along insulting surfaces.The influences of insulation materials,materials shape,amplitude of uniform field,and amplitude of pulse voltage on the streamer propagation are introduced.The achievements in streamer propagation along insulting surfaces are presented.Furthermore,many problems which can not be explained by existing theory are put forward to study intensively.