Design of insulated structure for load-ratio voltage power transformer by finite element method

Author

Xiang, Cui ; Jianxin, Liu ; Yucheng, Xie ; Ronggui, He ; Guoqiang, Zhang ; Chunping, Yang

Author_Institution

Dept. of Electr. Eng., North China Inst. of Electr. Power, China

Volume

30

Issue

5

fYear

1994

fDate

9/1/1994 12:00:00 AM

Firstpage

2944

Lastpage

2947

Abstract

For improving the insulation level of a 220 kV load-ratio voltage power transformer, two-dimensional and three-dimensional electric fields around the shielding ring of the regulative winding in this transformer have been precisely calculated by the finite element method. The calculated results show that the field intensity at the oil-corner for the shielding ring with the traditional oil-corner design is too high to insure an adequate insulation level for this transformer. Two new shielding ring structures without an oil-corner have been designed by using the finite element method. The maximum field intensity for each new design is reduced to 2.000 kV/mm from 2.633 kV/mm under 100 kV applied voltage

Keywords

electric fields; finite element analysis; power transformers; shielding; transformer insulation; 100 kV; 220 kV; FEM; field intensity; finite element method; insulated structure; insulation level; load-ratio voltage power transformer; oil-corner design; regulative winding; shielding ring; three-dimensional electric fields; two-dimensional electric fields; Boundary conditions; Dielectrics and electrical insulation; Finite element methods; Helium; Laboratories; Lagrangian functions; Oil insulation; Power systems; Power transformer insulation; Power transformers;

fLanguage

English

Journal_Title

Magnetics, IEEE Transactions on

Publisher

ieee

ISSN

0018-9464

Type

jour

DOI

10.1109/20.312554

Filename

312554