Corona charge characteristics in SF6 and N2 gases in a coaxial cylindrical electrode

The new gases or gas mixtures can be used in the electric power industry, provided they have a high dielectric strength with a sufficient high pressure at working temperature and they explore an economical advantage. This paper presents an experimental investigation on the corona activity in a coaxial electrode geometry in N₂, SF₆ and SF₆/N₂ mixtures. In this study the low content of N₂ in SF₆ reveals a reduction in the corona charge independent of the inner wire diameter and surfaces. Moreover, in these mixtures the prebreakdown corona occurs at a higher voltage. The corona frequency for different N₂ content in SF₆ records a lower level. The physical mechanisms underlying this phenomenon are discussed to through better understanding for further application