Long-term reliability of amorphous alloy wound core distribution transformers

Author

Ezure, S. ; Imai, Y. ; Sato, H. ; Yamada, S. ; Yamanaka, K. ; Saito, S.

Author_Institution

Tokyo Electr. Power Co. Inc., Japan

Volume

9

Issue

1

fYear

1994

fDate

1/1/1994 12:00:00 AM

Firstpage

249

Lastpage

256

Abstract

In order to verify long-term reliability of amorphous alloy wound core distribution transformers, accelerated aging tests and field trials used on actual transformers were practised. As for accelerated aging tests, short-circuit tests were added to imitate mechanical stress in operation on a utility´s distribution system. As a result, even after the equivalent of 30 years, which was the normal expected transformer´s life, the magnetic characteristic was unchanged, so these transformers could be operated. Additionally, two hundred transformers of four kinds were installed on a utility´s distribution system to study no-load characteristics. They were equipped with a mechanism to measure load current, background vibration and lightning surge current, so their influence on magnetic characteristic could be inspected. As a result, no remarkable change was seen even after six months

Keywords

ageing; distribution networks; life testing; power system reliability; power transformers; transformer cores; transformer testing; accelerated aging tests; amorphous alloy; background vibration; distribution system; electric utilities; field trials; lightning surge current; load current; long-term reliability; magnetic characteristic; mechanical stress; no-load characteristics; short-circuit tests; wound core distribution transformers; Accelerated aging; Amorphous magnetic materials; Amorphous materials; Current measurement; Lightning; Stress; System testing; Transformer cores; Vibration measurement; Wounds;

fLanguage

English

Journal_Title

Power Delivery, IEEE Transactions on

Publisher

ieee

ISSN

0885-8977

Type

jour

DOI

10.1109/61.277696

Filename

277696