Electric strength of insulating caps between transformer winding taps and structure elements

Author

Antonov, V.I. ; Danishina, A.A. ; Morozova, T.I.

Author_Institution

All-Union Electrotech. Inst., Moscow, USSR

fYear

1991

fDate

8-12 Jul 1991

Firstpage

1274

Abstract

It is experimentally shown that the electric strength of an insulated tap-plane insulation structure is influenced by the field stress appearing in the oil on the tap solid insulation surface and by the stressed oil volume bounded by an 80% equigradient surface. An analytical formula was obtained for the relationship between the stressed oil volume and the field stress at which a partial discharge of sufficiently high intensity starts in the oil-filled gap. The technique of estimating the electric strength, developed by using this formula, allowed the tap-plane insulation gap length to be decreased by 25-30% without reducing the insulation reliability

Keywords

electric strength; insulating oils; insulation testing; partial discharges; transformer insulation; electric strength; equigradient surface; field stress; insulating caps; insulation reliability; oil-filled gap; partial discharge; stressed oil volume; structure elements; tap-plane insulation structure; transformer winding taps; Circuits; Dielectric breakdown; Dielectrics and electrical insulation; Oil insulation; Partial discharges; Petroleum; Power transformer insulation; Proposals; Stress; Windings;

fLanguage

English

Publisher

ieee

Conference_Titel

Properties and Applications of Dielectric Materials, 1991., Proceedings of the 3rd International Conference on

Conference_Location

Tokyo

Print_ISBN

0-87942-568-7

Type

conf

DOI

10.1109/ICPADM.1991.172313

Filename

172313