Analysis of Cumulative Number and Polarity of Creeping Discharges Initiated at Solid/Liquid Interfaces subjected to AC Voltage
Résumé
This paper deals with the influence of voltage and the nature of solid sample on the cumulative number of creeping discharge events and their locations on one voltage cycle. It's shown that the total number of discharges recorded during 500 cycles of voltage increases significantly with the voltage. The threshold voltage U-i of discharges depends on the kind of material; and the average number of discharges (n(moy)) increases with the dielectric constant, epsilon(tau), of insulator. For instance, n(moy) is the highest for Bakelite (epsilon(tau) = 4.8) and the lowest for Polycarbonate (epsilon(tau) = 2.9). On the other hand, n(moy) of negative discharges seems to be slightly higher than that of positive ones whatever the solid sample and the amplitude of voltage.