Research on the Effect of Magnetic Field on Micro-Characteristics of Vacuum Arc During Arc Formation Process

The behavior of the vacuum arc under the action of the magnetic field and the evolution of the plasma parameters during arc formation process are of great significance for further understanding of the vacuum arc. In this paper, a mathematical model of micro-physical processes in vacuum arcs is established based on the drift-diffusion equation of gas dynamics, coupling the Poisson equation of the electric field, considering the collisions and recombination of electrons, ions and metal vapor molecules. Breakdown of the vacuum arc under the effect of magnetic field is simulated. Simulation results show that the plasma flows from the cathode to the anode under the action of the Lorentz force and the electron pressure gradient. With the increase of the axial magnetic field, the density of electrons and ions decreases, the temperature of the plasma decreases. The research work in this paper has some reference for the selection of the magnetic field in the vacuum arc breaking.