Prevention of dry-band arc damage on ADSS cables

All-dielectric cables separately suspended along high voltage overhead transmission routes are vulnerable to ageing through dry-band arcing. The differences between this process and dry-band arcing on traditional high voltage insulators are reviewed. Solutions to the problem on all-dielectric self supporting (ADSS) cables which involve the introduction of controlled conductivity into the cable are considered. Analysis suggests that arcs which are both electrically stable and spatially confined must be avoided. It is shown that the cable can be protected by limiting either the current or the voltage available to an arc. These considerations reveal that a semiconductive element does not have to cover the whole cable length to provide effective protection against dry-band arcing in this application. Index Terms--ADSS cable, dry-band arc, semiconductive, arc stability.