FEA Analysis and Optimization of Rotor Models in Permanent-Magnet Synchronous Motors fitted with Bonded Rare-Earth Magnets V. Abad, J. Sagredo, J. Gonzalez 2019/07/15

Abstract

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.

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.

References

[1] Toyota Global Newsroom. "Hybrid Model Global Sales Results".https://newsroom.toyota.co.jp/en/corporate/companyinformation/hybridsales/. Last access December 2018.
[2] Hsu, J., C. Ayers, and C. Coomer, Report on Toyota/Prius motor design and manufacturing assessment. 2004: United States. Department of Energy.
[3] Efficiency, E. and R. Energy, Evaluation of the 2010 Toyota Prius hybrid synergy drive system. 2011.
[4] Efficiency, E. and R. Energy, Evaluation of 2004 Toyota Prius hybrid electric drive system. 2006.
[5] Kaczmarek, R., Simulating the Toyota Prius electric motor. 2012, Cobham Technical Services.
[6] Abad, V. Sagredo J. "Evolución y proceso de fabricación de imanes “NEO” aplicados a motores de vehículos eléctricos." Revista de Metalurgia 54.3 (2018): 127.
[7] Hendershot, J., MotorSolve analysis of the 2010 Toyota Prius Traction Motor. 2015.
[8] Ley Josh, L.J., FreedomCAR Advanced Traction Drive Motor Development Phase I. UQM Technologies. Oak ridge National Laboratories, 2006: p. 84.
[9] Merwerth, J., J. Halbedel, and G. Schlangen, Electrical drive Widmer, J.D., R. Martin, and M. Kimiabeigi, Electric vehicle traction motors without rare earth magnets. Sustainable Materials and Technologies, 2015. 3: p. 7-13.
[10] Honkura, Y., Automotive motor innovation with anisotropic bonded magnet—MAGFINE. Journal of Iron and Steel Research, International, 2006. 13: p. 231-239.
[11] Kamiya, M., Development of traction drive motors for the Toyota hybrid system. IEEJ Transactions on Industry Applications, 2006. 126(4): p. 473-479.