DC creepage breakdown characteristics of oil-immersed insulation

Author

Ebisawa, Yoshihito ; Yamada, Shin ; Mori, Shigekazu ; Teranishi, Tsuneharu

Author_Institution

Toshiba Corp., Kawasaki, Japan

Volume

16

Issue

6

fYear

2009

fDate

12/1/2009 12:00:00 AM

Firstpage

1686

Lastpage

1692

Abstract

This paper deals with dc creepage breakdown characteristics of oil-immersed insulation in HVDC transformers. The authors investigated dc breakdown characteristics using element insulation models and a full-scale model with a high creepage electric field on the insulation surfaces. The results are as follows: The dielectric strength of creepage insulation in non-contact with electrodes was more than twice higher that of creepage insulation in contact with bare electrodes. The dielectric strength is dependent on the creepage distance of surface insulation and decreases to about 45% in case of surface insulation with ten times creepage distance.

Keywords

HVDC power convertors; electric breakdown; electric strength; power transformer insulation; DC creepage breakdown characteristics; HVDC transformers; dielectric strength; element insulation models; high creepage electric field; oil-immersed insulation; surface insulation; Analog-digital conversion; Breakdown voltage; Dielectric breakdown; Dielectrics and electrical insulation; Electric breakdown; Electrodes; Oil insulation; Petroleum; Power transformer insulation; Solids; Converter transformer, oil-immersed insulation, creepage, insulation, breakdown stress;

fLanguage

English

Journal_Title

Dielectrics and Electrical Insulation, IEEE Transactions on

Publisher

ieee

ISSN

1070-9878

Type

jour

DOI

10.1109/TDEI.2009.5361590

Filename

5361590