Carter's factor calculation using domain transformations and the finite element method

Abstract

SUMMARY The main purpose of this work is to present a methodology to calculate Carter's factor using the actual air‐gap geometry, that is, without simplifications of the slot geometry. The methodology is based on the finite element method, and its results are compared with some traditional procedures used for Carter's factor calculation and also with a domain transformation technique. It is shown that the finite element method and the domain transformation methodologies present similar results, which are different from the results obtained with traditional procedures. Copyright © 2011 John Wiley & Sons, Ltd.

Calculation of the influence of slot geometry on the magnetic flux density of the air gap

“…Changing its main constructive parameters, it is possible to observe changes in slot pattern. In then quantifies flux's uniformity [1], [13], [14]. A small induction machine stator inspired the initial values of the slot.…”

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A Semi-Anaytical Model for the Analysis of a Permanent Magnet Tubular Linear Generator

“…Once the solution of the semi analytical model has been obtained, the slot leakage flux and average distribution of flux density in the teeth are evaluated by approximated formulas [24]- [25]. The effects of the presence of the slots can be taken into account by introducing the Carter coefficient [26] and equivalent current sheets.…”

Tubular Linear Induction Machine as a Fast Actuator: Analysis and Design Criteria

“…Analytical models can be obtained by using a simplified structure with a smooth stator and with the primary windings substituted by an equivalent current sheet. The use of the Carter coefficient allows to evaluate the equivalent air gap and a proper positioning of the current sheet [30][31][32]. Defining g 0 as the distance between the iron-massive part of the mover and the inner part of the stator, the Carter airgap is given by:…”