An alternative simulation approach for surface flashover in a vacuum using a 1D2V continuum and kinetic model

Abstract

Surface flashover across insulator in vacuum is a destructive plasma discharge which undermines the behaviors of a range of applications in electrical engineering, particle physics, space engineering, etc. This phenomenon is widely modeled by the particle-in-cell (PIC) simulation, here the continuum and kinetic simulation method is first proposed and implemented as an alternative solution for flashover modeling, aiming for the prevention of the unfavorable particle noises in PIC models. A 1D2V (one dimension in space, two dimensions in velocity) kinetic simulation model is constructed. Modeling setup, physical assumptions, and simulation algorithm are presented in detail, and a comparison with the well-known secondary electron emission avalanche (SEEA) analytical expression and existing PIC simulation is made. Obtained kinetic simulation results are consistent with the analytical prediction, and feature noise-free data of surface charge density as well as fluxes of primary and secondary electrons. Discrepancies between the two simulation models and analytical predictions are explained. The code is convenient for updating to include additional physical processes, and possible implementations of outgassing and plasma species for final breakdown stage are discussed. The proposed continuum and kinetic approach is expected to inspire future modeling studies for the flashover mechanism and mitigation.

Particle traps constructed on the insulator of conductive slip rings for surface flashover mitigation under particle adhesion

“…The simulation process and principles are detailed in the previous paper. 24,25 The simulation results are shown in Fig. 6.…”

The mechanism of EP/SiC coating modulated DC flashover characteristics of epoxy composites in SF6/N2 mixtures

“…However, owing to the long-term DC supply, space charges accumulate on their surfaces, which distorts the spatial electric field and causes surface flashover along the insulator (gas-solid interface) [1][2][3]. Surface flashover, which occurs before gas/solid breakdown because of the complex competing charge transport processes in gas, gas-solid interfaces, and solids, is a random, unpredictable, and inevitable statistical discharge phenomenon associated with the insulator in a GIS/GIL [4,5]. The high-energy arc generated in the surface flashover channel degrades the surface materials and significantly reduces their insulation endurance under high voltage causing insulation failure of the GIS/GIL and threatening the secure operation of the electrical power grid [6][7][8].…”