真空电弧阴极斑点群集聚的主导作用研究

On the Leading Role by Constriction of Cathode Spots Group of the Vacuum Arc

利用动态图像高速微机系统，对真空电弧纵向磁场触头燃弧及重燃过程进行了动态拍摄，对比分析了不同开距下宏观动态图像、微观电子密度和电弧中心光强的不同时域特征．指出高电压等级真空电弧纵向磁场下小开距阴极斑点群先行集聚也会导致阳极斑点形成，且重燃点仍在原阴极，并对此现象作了解释．

The progress of striking and restriking of the vacuum arc at the contacts in an axial magnetic field has been photographed with a microcomputer-based high-speed camera system for dynamic images. Under different gap-spacing conditions, the time-domain features of the macro-dynamic images, microelectron densities and light intensites in the arc center are analyzed. It is shown that, in short gap-spacing, the cathode spot group under a high voltage level of the vacuum arc are first constricted, which leads to the forming of anode spots. However, arc restriking is initiated at the cathode. These phenomena are explained.