A new approach for dielectric breakdown calculation of residual hot gas after arc burning based on particle transport and Boltzmann analysis

Abstract

The calculation of critical electrical field, based on the balancing between the ionization and attachment of the electrons, has been widely used to obtain the dielectric breakdown strength of hot gas after arc burning. However, due to the negligence of electron drift, diffusion and photon ionization process and geometry of electrodes, this method should be further improved. In this work, a new approach for the dielectric breakdown calculation of residual hot gas has been established by combining particle transport calculation and Boltzmann analysis, which considers both the influence of dissociations and strong electrical field. The method has been applied in the evaluation of SF6 dielectric breakdown, which is a commonly used gas media in the field of switch gears. The influences of temperature, pressure and electrode distance have also been investigated. The results in this calculation agree well with the previous test, indicating its potential to predict the dielectric breakdown more accurately.