Frequency dependent eddy current models for nonlinear iron cores

Author

Tarasiewicz, E.J. ; Morched, A.S. ; Narang, A. ; Dick, E.P.

Author_Institution

Ontario Hydro System Planning, Ottawa, Ont., Canada

Volume

8

Issue

2

fYear

1993

fDate

5/1/1993 12:00:00 AM

Firstpage

588

Lastpage

597

Abstract

Frequency dependent representations of eddy currents in laminated cores of power transformers are developed. One representation is based on a continued fraction expansion for the frequency dependent magnetizing impedance while the other is based on a discretization of flux distribution within the lamination. Both models are low order and reproduce the frequency characteristics of the transformer magnetizing branch up to 200 kHz with less than 5% error. The importance of modeling the frequency dependence of eddy currents for the calculation of the transient recovery voltage across a low voltage transformer breaker interrupting a nearby fault is demonstrated

Keywords

eddy currents; power transformers; transformer cores; eddy currents; flux distribution; frequency dependent magnetizing impedance; laminated cores; low voltage transformer breaker; nonlinear iron cores; power transformers; transient recovery voltage; Eddy currents; Frequency dependence; Impedance; Iron; Lamination; Low voltage; Magnetic cores; Magnetic flux; Power transformers; Transformer cores;

fLanguage

English

Journal_Title

Power Systems, IEEE Transactions on

Publisher

ieee

ISSN

0885-8950

Type

jour

DOI

10.1109/59.260823

Filename

260823