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

Volume

14

Issue

3

fYear

1999

fDate

7/1/1999 12:00:00 AM

Firstpage

1081

Lastpage

1089

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;

fLanguage

English

Journal_Title

Power Delivery, IEEE Transactions on

Publisher

ieee

ISSN

0885-8977

Type

jour

DOI

10.1109/61.772357

Filename

772357