Acoustic signals from corona discharges in gis

Abstract

Acoustic methods are proven sufficiently sensitive to detect discharges on live parts in GIS. This paper discusses how the sensitivity depends on the material properties of the SFr, gas and the enclosure, as well geometry of the GIS. In particular, the effect of dispersive wave propagation in the enclosure and the very significant frequency dependent absorption in the gas are discussed. The analyses are based on measurements of the sound absorption in SF/sub 6/ and frequency of signals from discharges in a GIS.