Pseudo-Three-Dimensional Analytical Model of Linear Induction Motors for High-Speed Applications

Abstract

Literature on linear induction motors (LIMs) has proposed several approaches to model the behavior of such devices for different applications. In terms of accuracy and fidelity, field analysis-based models are the most relevant. Closedform or numerical solutions can be derived, based on the complexity of the model and the underlying hypotheses. In terms of simplicity, equivalent circuit-based models are the most effective, since they can be easily integrated into optimization frameworks. To the best of the authors' knowledge, the literature has not yet provided a computationally efficient LIM analytical model that considers the main characteristics of this type of motor altogether (i.e. finite motor length, magnetomotive force (mmf) space harmonics, slot effect, edge effect, and tail effect) and that is numerically and experimentally validated, especially at high speed (i.e. v ≃ 100 m s −1 ). Within this context, this paper proposes a field analysis-based pseudo-three-dimensional model of LIMs that explicitly takes into account the above-mentioned effects. The derived closed-form solution makes the model computationally more effective than traditional f.e.m. models and, therefore, suitable to be coupled with optimization frameworks for optimal LIM design. The performance and accuracy of the proposed model are assessed through numerical simulations and experimental measurements, carried out by means of a dedicated test bench.