Effect of stacking method and clamping on distribution transformers built with amorphous magnetic material

Author

Basak, A. ; Moses, A.J. ; Yasin, M.R.

Author_Institution

Sch. of Electr., Electron & Syst. Eng., Univ. of Wales Coll. of Cardiff, UK

Volume

27

Issue

6

fYear

1991

fDate

11/1/1991 12:00:00 AM

Firstpage

5196

Lastpage

5198

Abstract

Work on stacked cores assembled from amorphous POWERCORE strip is described. The effect of the stacking method and clamping on power loss is shown. A 100 kVA, 3-phase, 3-limb core was assembled using a 105-mm-wide, 0.14-mm-thick amorphous POWERCORE strip. The core had 45°-90° T joints and 45° mitred corner joints with 10-mm overlap lengths. It was built up to various stack heights with laminations stacked in single, double, and quadruple layers. It was found that the power loss increases with stack height and layer number. The localized power loss was 10% higher in a stack of 500 laminations than that in a stack of 100 laminations at 1.3 T. Use of aluminium clamps reduced the losses of the full size core from 0.43 W/kg to 0.33 W/kg at 1.35 T due to a reduction in stray flux or improvement in internal flux uniformity

Keywords

magnetic properties of amorphous substances; power transformers; transformer cores; transformer testing; 1 to 1.4 T; 100 kVA; amorphous POWERCORE strip; amorphous magnetic material; clamping; distribution transformers; internal flux uniformity; laminations; layer number; power loss; reduction in stray flux; stack height; stacked cores; stacking method; Amorphous magnetic materials; Amorphous materials; Assembly; Clamps; Lamination; Magnetic cores; Stacking; Stress; Strips; Transformer cores;

fLanguage

English

Journal_Title

Magnetics, IEEE Transactions on

Publisher

ieee

ISSN

0018-9464

Type

jour

DOI

10.1109/20.278785

Filename

278785