Changes of Electrical Conductivity and Temperature Caused by Electrode Erosion for Atmospheric Plasma Systems

Abstract

Electrode erosion is indispensable for atmospheric plasma systems, as well as for switching devices, due to the high heat flux transferred from arc plasmas to contacts, but experimental and theoretical works have not identified the characteristic phenomena because of the complex physical processes. In this study, we analyzed the electrical conductivity and the temperature of arc plasmas using the field-coupled computational techniques to consider the electrode erosion in a thermal puffer plasma chamber. Based on the results from the arcing history with metallic vapors, the thermal and electromagnetic characteristics near current zero were investigated using the electrical conductivity and the temperature of the arcing zone. Numerical results showed that the existence of electrode vapors made the arc temperature down during the high-current period and a negative effect with high electrical conductivity on the current interruption.