Analysis of decomposition by-products and its formation mechanism of SF6/N2 mixed gases under spark discharge

The greenhouse effect caused by SF₆ gas in the power industry can not be ignored, and the use of SF₆/N₂ mixture gas instead of pure SF₆ has become an important means. In order to explore the regulation of SF₆/N₂ gas mixture decomposition components, a series of spark discharge experiments were carried out. The technical problem of rapid and effective detection of trace components was solved by gas chromatograph combined with copper tube gas entrapment technology, and the qualitative and quantitative detection of SF₆/N₂ gas mixture decomposition components were achieved. The changes of SF₆/N₂ decomposition components under different mixing ratios and different spark discharge times were analysed. The experimental results show that the decomposition components of SF₆/N₂ gas mixture under spark discharge mainly include SO₂F₂, SOF₂, SO₂, CF₄, CH₄, NF₃, CO₂, N₂O, C₂F₆, etc. Among them, NF₃ and N₂O can be used as the characteristic products of SF₆/N₂ gas mixture under spark discharge. The density of these two components was positively correlated with the discharge times. On the basis of the experimental study, the energy of the main decomposition path was calculated by using density functional theory, and the variation law of component density was analysed.