The model law for SF6 insulated systems

The variation of probability of the electrical breakdown of gases as a result of varying the interelectrode gap value is considered. The relevant analytical expressions have been obtained by treating the electrical discharge of gases as avalanche processes in real space and, in the sense of Markov processes, in the probability space. Parameters of the theoretical model are determined experimentally, while the whole model is experimentally verified. A rather good agreement between the results obtained experimentally and those anticipated theoretically is achieved for the surface change by a factor of ten concerning and also for the interelectrode gap change by the same factor. The experiments were carried out with the gas SF₆. The absolute pressure was varied from 0.5 to 7 bars.