Investigation of the losses in the stator duct spacers of large AC motors using the A-ψ 3-D eddy current formulation

Author

Flack, Timothy J. ; Williamson, Stephen

Author_Institution

Cambridge Univ., UK

Volume

32

Issue

3

fYear

1996

fDate

5/1/1996 12:00:00 AM

Firstpage

1557

Lastpage

1560

Abstract

This paper describes how the A-ψ formulation may be applied to determine the losses in the stator duct spacers of large AC motors. The model is described in terms of its geometry and boundary conditions. The novel aspects of the application of the formulation to this problem are explained. These include the modelling of fixed currents sources (the stator windings), the location of the necessary cut surfaces and the determination of their magnetic scalar potential differences, and the implementation of periodic boundary conditions for vector variables. Results are presented showing how the duct spacer losses vary with load, and with the relative permeability of the spacer material. The effects of modelling iron nonlinearity, of both the spacer and the steel laminations, are also illustrated

Keywords

AC motors; eddy current losses; electromagnetic fields; laminations; losses; machine theory; stators; A-ψ 3-D eddy current formulation; boundary conditions; cut surfaces location; fixed currents sources; geometry; iron nonlinearity modelling; large AC motors; magnetic scalar potential differences; periodic boundary conditions; relative permeability; stator duct spacer losses; stator windings; steel laminations; vector variables; AC motors; Boundary conditions; Ducts; Geometry; Iron; Magnetic materials; Permeability; Solid modeling; Stator windings; Steel;

fLanguage

English

Journal_Title

Magnetics, IEEE Transactions on

Publisher

ieee

ISSN

0018-9464

Type

jour

DOI

10.1109/20.497548

Filename

497548