Dielectric properties of SF6 mixtures containing oxygen and other gases

Conclusion This paper has explored the influence of an oxygen addition on the dielectric strength of the SF₆ by numerically solving the Boltzmann equation with given cross section data. The linear variation of the dielectric strength with a mole fraction of oxygen was obtained. Similar calculations were performed for SF₆ + air for which only approximative estimates had existed in the literature. To check the results and for other practical reasons the method of the Boltzmann equation was applied to the SF₆ + He and SF₆ + N₂ mixtures, the dielectric strength of which had already been explored by other authors. In comparison with other mixtures currently studied the SF₆ + O₂ mixture reveals rather poor dielectric properties. In spite of the fact that the oxygen is an attaching gas, its addition to SF₆ and its mixtures spoils the dielectric strength. This numerical analysis exactly qualified this behaviour and it is in agreement with the few available experiments.