不同微槽结构绝缘子真空沿面闪络特性  

Characteristics of grooved insulator flashover under pulsed voltage

作　　者：李逢[1] 王勐[1] 任靖[1] 方东凡[1] 康军军[1] 徐乐[1] 杨尊[1] 

机构地区：[1]中国工程物理研究院流体物理研究所、脉冲功率科学与技术重点实验室,四川绵阳621900

出　　处：《强激光与粒子束》2014年第4期299-303,共5页High Power Laser and Particle Beams

基　　金：国家自然科学基金项目(50937004,51277168,51307155)

摘　　要：针对单极性脉冲电压下不同微槽结构绝缘子真空沿面闪络特性开展实验研究。根据二次电子运动特性,设计了多种微槽宽度,对比了微槽结构和平面结构的绝缘子耐压特性差异。槽宽为1mm的微槽样品耐压水平与平面结构样品耐压水平相当,槽宽小于1mm的样品组耐压水平均高于平面结构样品,最高电压提高倍数约为1.4,说明一定尺寸范围内的微槽设计将提高绝缘子真空耐压水平。通过电场强度计算分析微槽结构对二次电子运动的影响过程可知,较大的微槽宽度可使电子限制在槽内运动,较小的微槽宽度将抑制初始电子的发展,最终二者都能达到抑制闪络的目的。通过显微镜观测各组样品表面特征,材料表面微观缺陷将可能降低材料耐压水平。The characteristics of grooved insulator flashover under pulsed voltage are discussed in this paper.The groove widths are determined by the secondary electron emission trajectory.The experiments results show that the flashover voltages increased while the insulator samples with 0.05mm,0.1mm,or 0.7mm wide grooves were used and the biggest voltage multiple was 1.4.The samples with 1mm wide grooves had the same flashover voltage level as the flat ones.It is concluded that proper grooves design could increase the insulator flashover level by preventing the development of the secondary electron emission avalanche.Mechanism of inhibition was analyzed with calculation of electric field strength on the surface of insulator.Wider grooves, would trap the electrons and narrower ones would inhibit the motion of the initial electrons.Comparing the samples surface micrograms,a conclusion was given that the surface micro-flaw would drop the insulator flashover level.

关 键 词：真空沿面闪络 表面微槽 单极性脉冲电压 二次电子 

分 类 号：TM835.4[电气工程—高电压与绝缘技术]