Measurement of transient temperature distribution at anode surface after current zero in vacuum interrupter

In vacuum interrupters, an insulation ability is degraded immediately after high current interruption, because of thermal electrons, metal vapors, and residual plasma. Thermal electrons and metal vapors are produced from the electrode surface, which is heated by the arc between electrodes. Therefore electrode temperature is affect insulation ability. It is important to measure the transient of temperature distribution at anode surface after current zero, for explication of interruption phenomenon in vacuum. Hence, two color pyrometer method with a high-speed camera for temperature measurement of electrode in vacuum was developed, and temperature of Cu-Cr spiral test electrode was measured after current zero by its method and time change of temperature distribution at anode wad obtained. Also, relationship between interruption current and time change of anode temperature was investigated.