FEM-study on converter transformer failures in the Celilo HVDC converter station

Author

Elliott, F.E. ; Lavier, B.E. ; Kuehn, W.P. ; Kuechler, A.

Author_Institution

Bonneville Power Adm., Portland, OR, USA

Volume

2

fYear

1999

fDate

31 Jan-4 Feb 1999

Firstpage

1047

Abstract

Two converter transformer failures occurring at the Celilo terminal of the Pacific Intertie HVDC transmission system, (one during commissioning in 1989 and one in operation in 1995), caused considerable concern regarding the reliability of the remaining converter transformers. These failures and discoloration of bushing porcelains observed during maintenance demanded a review of electric field stresses. This was done using a FEM field simulator and building a model which most accurately reflects the bushing/transformer arrangement with regard to the shape and data of the various conducting and insulating materials. Study results show that factory tests do not necessarily cover actual service stresses. Also the magnitude of the stress within critical areas might exceed withstand capabilities.

Keywords

HVDC power convertors; bushings; failure analysis; finite element analysis; porcelain insulators; power transformers; substations; Celilo HVDC converter station; FEM; FEM field simulator; Pacific Intertie HVDC transmission system; bushing porcelains discoloration; commissioning failure; conducting materials; converter transformer failures; electric field stresses; insulating materials; maintenance; operation failure; reliability; Conducting materials; HVDC transmission; Insulators; Maintenance; Porcelain; Power transformer insulation; Production facilities; Shape; Stress; Testing;

fLanguage

English

Publisher

ieee

Conference_Titel

Power Engineering Society 1999 Winter Meeting, IEEE

Print_ISBN

0-7803-4893-1

Type

conf

DOI

10.1109/PESW.1999.747346

Filename

747346