Analysis of arc behavior and electrode surface temperature in spiral electrode of vacuum interrupter

In vacuum interrupters, its insulation ability is immediately degraded after high current interruption, because of the presences of thermal electrons, metal vapors and residual plasma. These thermal electrons and metal vapors are produced from the electrode surface which is heated by the arc between two electrodes. A kind of electrode on which the arc rotates is called spiral electrode. It is considered that the spiral electrode inhibits excessive temperature rise of the electrode surface by rotating the arc. However, the influence of arc behavior on this electrode-surface temperature is not fully understood. Therefore, by means of simultaneously performing arc photography with a high-speed camera, and measuring temperature of the electrode surface with the two-color pyrometer method, the relationship between the arc condition and the electrode temperature after the current zero was investigated. As a result, it was found that the position at which the arc stagnation immediately before current zero had an influence on the temperature distribution after the current zero.