Synergistic effect of the insulation characteristics of gas mixtures under the influence of pulse voltages

The character of the paper is purely experimental. The pulse breakdown voltage as well as impulse characteristics of the SF
₆
+He and SF
₆
+N
₂
gas mixture were examined by reliable and highly reproducible procedure. The obtained results were compared to the matching results for the pure SF
₆
gas (that was obtained under the same conditions). It was found that the positive synergy of the SF
₆
+He gas mixture is higher than the positive synergy of the SF
₆
+N
₂
gas mixture. That result was explained by more appropriate moderation effect of the He atom (than the N
₂
molecule) at the conditions of the fast pulse voltages. The results shown in this paper are significant for engineering practice in the fields where an efficient replacement of the pure SF
₆
gas is required as an insulation gas in the conditions of rapid overvoltage effect.