Title :
Aging of nonceramic insulators due to corona from water drops
Author :
Phillips, A.J. ; Childs, D.J. ; Schneider, H.M.
Author_Institution :
Univ. of the Witwatersrand, Johannesburg, South Africa
fDate :
7/1/1999 12:00:00 AM
Abstract :
The fundamental principles of water drop corona as an aging mechanism for nonceramic insulators are presented. It is demonstrated that water drops in the sheath regions enhance the electric field and may cause corona which can play an important role in long-term performance. Electric field enhancement caused by water drops in different locations on the shed and sheath are demonstrated by means of electric field calculations and small scale experiments. The threshold magnitude of the surface electric field for corona from water drops is presented for two silicone rubber surfaces having different hydrophobic properties. The effect of water drop corona activity on the properties of the surface material is shown using small scale aging experiments
Keywords :
ageing; corona; drops; electric fields; silicone rubber insulators; water; electric field calculations; electric field enhancement; hydrophobic properties; nonceramic insulators aging; sheath regions; shed; silicone rubber insulators; silicone rubber surfaces; surface electric field; surface material; threshold magnitude; water drop corona onset; Accelerated aging; Contamination; Corona; Degradation; Dielectrics and electrical insulation; Insulator testing; Leakage current; Power transmission lines; Rubber; Water;
Journal_Title :
Power Delivery, IEEE Transactions on
