FEA Analysis and Optimization of Rotor Models in Permanent-Magnet Synchronous Motors fitted with Bonded Rare-Earth Magnets

V. Abad, J. Sagredo, J. Gonzalez



The Toyota Prius MG2 electric motor and itsupgrades, since its first appearance in 1997, are presented in this paper. This electric motor has an Interior Permanent Magnet (IPM) fitted with Rare Earth (RE) magnets, which presents clear advantages over the more widely used Induction Motors (IM). The principal advantage is its high power-density value that makes it a leader in the Electric Vehicles (EV) market. This technology, however, faces a problem, in so far as the global production of RE magnets is an exclusive monopoly of China, (motivating the United States and Japan, among others, to investigate alternative systems). In this paper, the proposal is to substitute the sintered magnet in current use by the bonded type of magnet. The use of bonded magnets permits curved geometric forms, reducing the use of dysprosium, one of the most controversial elements of sintered magnets. These materials are compared using Finite Element Analysis (FEA) in the design of various rotor models including the proposal of a model with bonded magnetic materials, with the advantages of curved magnets and a dual layer arrangement. The proposed rotor model yielded a considerably higher power density than the model developed by Toyota.

Published in: Renewable Energy & Power Quality Journal (RE&PQJ, Nº. 17)
Pages: 37-42 Date of Publication: 2019/07/15
ISSN: 2172-038X Date of Current Version:2019/04/10
REF: 212-19 Issue Date: July 2019
DOI:10.24084/repqj17.212 Publisher: EA4EPQ

Authors and affiliations

V. Abad1, J. Sagredo1, J. Gonzalez1
1. Electromechanical Department, Polytechnical School of Burgos University. Campus Vena, Burgos, Spain

Key words

PMSM, Finite Element Analysis, Rare Earth Magnets.


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