The Influence of Ionization and Attachment Coefficients on Positive Corona Onset Characteristics in Dry or Moist Air

Abstract

Ionization and attachment coefficients (IAC) are essential in corona discharge research. However, these parameters of air from different sources vary and are environment-affected. In the present work, the commonly used IAC data in corona discharge research are compared with the data of air calculated by the Monte Carlo (MC) simulation and the Boltzmann equation with different collision cross sections. The results are significantly influenced by both the collision cross sections and the calculation method, and additionally, the effect of humidity on the results is studied. Subsequently, the corona onset voltage of the wire–plane electrode is predicted by the photoionization criterion and measured in an artificial climate chamber. For the first time, the impact of IAC differences on the prediction of positive corona onset voltage under varying environments is analyzed. Experimental comparisons reveal that the impact is marked, especially under varying humidity conditions, where the impact trends are opposite. To ensure the comprehensiveness of the research, the photon absorption coefficient is also analyzed. Finally, according to the comparisons, recommendations for parameter acquisition methods in positive corona discharge research are provided, which will offer valuable insights for addressing corona discharge issues in various environments.