长间隙真空电弧形态演变过程观察

Observation on Model Transition Procedure of Long Gap Vacuum Arc

应用设计制作的真空电弧图像瞬态摄像系统，对长间隙下（开距４０ｍｍ）不同时刻的真空电弧图像进行了拍摄，获得了真空电弧形态演变过程．通过外加线圈对灭弧室触头间施加纵向磁场，保持了大电流下电弧为扩散型，降低了电弧电压．通过观察电流过零后的真空电弧图像，发现了真空电弧的重燃点位置。

By using a self made CCD Optical Transient Image System, the vacuum arc images of long gap (40 mm) at various moments are taken photos, and the regular pattern of the vacuum arc mode transition is studied. Adding axial magnetic field by outside coil, the arcs keep diffuse mode at higher current, and the arc voltage is reduced. By observing the arc images after current zero, the reignition initial spot at the side of electrode is found, and the elimination method is presented.