Particle-in-cell simulation of vacuum arc breakdown process of tip-to-plate electrode configuration

Abstract

The breakdown of a vacuum arc under high applied voltage conditions usually occurs on very short time and space scales, and a deep understanding of these processes is essential to extend the application of vacuum arc devices. To study the time and spatial evolution of plasma parameters during vacuum breakdown, a two-dimensional axial-symmetric particle-in-cell code with Monte Carlo collisions is used in the numerical simulation of tip-to-plate electrode configuration. In this simulation, in addition to considering the primary and secondary ionization of copper atoms, the excitation and de-excitation processes of copper atoms are also introduced so that the evolution of the light intensity of the vacuum arc in the different stages of breakdown processes can be obtained by tracking the de-excitation process of the atoms, which can be considered a virtual camera. In this way, the cathode radiance, anode light expansion, arc channel establishment, and arc quenching processes can be visually observed, and the trends are consistent with the images taken by Intensified Charge-Coupled Device (ICCD) and streak cameras reported in the literature. The analysis of the sputtering amount of the anode material due to the impact of the cathode plasma to the anode surface shows that the contribution of atoms, singly, and doubly ionized ions to the sputtering of the anode material varies at different stages of the discharge.