Damage resulting from long term slot discharge activity in a hydrogen environment

Author

McDermid, W.

Author_Institution

Manitoba Hydro, Winnipeg, Man., Canada

fYear

1990

fDate

3-6 Jun 1990

Firstpage

361

Lastpage

362

Abstract

Two 17-kV, 160 MVAr hydrogen-cooled synchronous condensers were recently rewound. They had operated since original installation with significant slot discharge activity. At the time of rewind the original stator bars were inspected to determine the extent of the slot discharge and vibration related damage to the groundwall insulation. It was found that inadequately side packed and wedged stator windings are subject to significant erosion from slot discharge and vibration even in a hydrogen environment. A semiconducting coating painted over the cured groundwall insulation may not be durable. It is concluded that wedging materials should be chosen to better enable a stator winding to withstand short-circuit forces

Keywords

electric breakdown of gases; hydrogen; stators; synchronous machines; 160 MVAr; 17 kV; H₂ cooled synchronous condenser; groundwall insulation damage; long term slot discharge activity; semiconducting coating; short-circuit forces; stator bars; stator windings; vibration; wedging materials; Fault location; Hydrogen; Insulation; Manufacturing; Partial discharge measurement; Partial discharges; Probes; Stator bars; Stator windings; Testing;

fLanguage

English

Publisher

ieee

Conference_Titel

Electrical Insulation, 1990., Conference Record of the 1990 IEEE International Symposium on

Conference_Location

Toronto, Ont.

ISSN

1089-084X

Type

conf

DOI

10.1109/ELINSL.1990.109773

Filename

109773