Analysis of statistical nature of electrical breakdown time delay in nitrogen at 6.6 mbar pressure in presence of positive ions and N(⁴S) atoms

Abstract

Key words Electrical breakdown time delay, breakdown voltage, afterglow period, neutral active states.On the basis of the mean value of electrical breakdown time delay t d and the standard deviation of electrical breakdown time delay σ dependence on the afterglow period τ , the mechanisms which dominantly influence to breakdown initiation in nitrogen were separated. It was shown that the positive ions formed in mutual collision of long-lived metastable molecules have a dominant role in breakdown initiation for τ values up to 70 ms. The metastable molecules were derived from previous breakdown and discharge. In this case σ t d and the total time delay t d is approximately equal to formative time t f which decreases in value with the increase of overvoltage. When positive ions have a dominant role in the breakdown initiation the Gaussian distribution describes data of t d ≈ t f very well. For τ > 1 s, N ( 4 S) atoms formed in previous breakdown and discharge, have a dominant role in the breakdown initiation. Then, σ ≈ t d and Laue's distribution, which is valid for statistical time delay ts, describes t d data very well.

The evolution of breakdown voltage and delay time under high overvoltage for different types of surge arresters

“…This is something which indicates instability in the operation of the component with respect to the delay time. In the earlier results [22][23][24][25] of the memory effect study, it can be seen that in the region of increase for most experimental conditions ts is less than tf, as well as that the standard deviation of tf is very small, in the analysis of total delay time, in the first approximation we can assume that under constant experimental conditions, it is deterministic. In this case, the delay time becomes the sum of one deterministic tf and one stochastic quantity ts, so it takes on its stochastic character from the statistical delay time.…”