Computation of induction machine inductances for extended analytical modeling accounting for saturation

¹ L2EP (UPRES 2697), École Centrale de Lille, B.P. 48, 59651 Villeneuve d'Ascq, France
² LESiR (UPRES A CNRS 8029), ENS de Cachan, 61 avenue du Président Wilson, 94235 Cachan, France
³ LGEP (UMR CNRS 8507), ESE, plateau du Moulon, 91192 Gif-sur-Yvette, France

Corresponding author: betty.semail@eudil.fr

Received: 15 December 1997
Revised: 30 September 1998
Accepted: 15 December 1998
Published online: 15 March 1999

Abstract

In this paper, finite element method is used to compute inductance parameters of a squirrel cage induction machine. To take into account saturation effect, saturated equivalent parameters are introduced, which depend on the instantaneous value of the magnetising current. For a balanced induction machine, the particular inductance behaviors allow straightforward flux expressions without any cross saturation effect. Moreover, these expressions are explained thanks to an extended analytical approach considering a magnetic saliency phenomenon by a second order air-gap permeance. A simple way of transformation ratio and leakage inductance computation is also deduced. The numerical results show the compatibility between finite element approach and extended analytical Park's method. Besides, two operating points (at no load and for nominal speed) studied by the both methods give very closed results.