Modeling of the near Electrode Physics for Simulation of Arc

This paper presents a numerical model of physical phenomena taking place between the contacts of a switchgear device during fault. Particularly the regions adjacent to cathode and anode are modeled in MATLAB. The effect of system impedance on arc current has been considered. A numerical model of near electrode physics is solved to predict the arc behavior with the design parameters like electrode materials, pressure, impedance etc. With this model we can identify the interface behavior of plasma and electrode; this is done by identifying the layers like sheath and ionization based on the temperature distribution. This model solves the equations of cathode region (cathode surface, sheath and ionization zone) and anode region (Anode surface, sheath and ionization zone) to evaluate their effect on the total arc voltage in a 2-D simulation (z, t) in MATLAB. The same can be extended to 4-D simulation (x,y,z,t) with CFD tools for which work is in progress.