A Design Approach for Coaxial Magnetic Gear and Determination of Torque Capability

Document Type : Article


Department of Mechanical Engineering, Sharif University of Technology, Tehran, Iran


This paper presents a time saving methodology for design and sizing the magnetic gear sets. Some new design parameters similar to mechanical gears are defined to calculate the torque capacity based on these. Finite element analysis is extensively used to calculate the variation of gear set torque capacity due to changes in different geometric parameters of a set. Different design curves are obtained by which the design and sizing of the gears can routinely be accomplished. Optimal performance of magnetic gear wasn’t the main target of this research and just this method helps gear designers to decide on parameters such as scale of gears, magnet thickness, stack length and pole pair numbers and come up with a close to optimum geometry design


Main Subjects


1. Atallah, K. and Howe, D. \A novel high-performance
magnetic gear", IEEE Transactions on Magnetics, 37,
pp. 2844-2846 (2001).
2. Atallah, K., Wang, J., and Howe, D. \A highperformance
linear magnetic gear", Journal of Applied
Physics, 97, pp. 1-3 (2005).
3. Joergensen, F.T., Andersen, T.O., and Rasmussen,
P.O. \The cycloid permanent magnetic gear", In Conference
Record - IAS Annual Meeting (IEEE Industry
Applications Society), Tampa, FL, pp. 373-378 (2006).
4. Mezani, S., Atallah, K., and Howe, D. \A highperformance
axial- eld magnetic gear", Journal of
Applied Physics 99, 08R303, pp. 1-3 (2006).
5. Rens, J., Atallah, K., Calverley, S.D., and Howe,
D. \A novel magnetic harmonic gear", In Proceedings
of IEEE International Electric Machines and
Drives Conference, IEMDC 2007, Antalya, pp. 698-
703 (2007).
6. Man, Y., Zhao, Y., Bian, C., Wang, S., and Zhao,
H. \A kind of magnetic gear with high speed ratio",
In Proceedings-3rd International Conference on Information
Sciences and Interaction Sciences, ICIS 2010,
Chengdu, pp. 632-634 (2010).
7. Jian, L.N., Chau, K.T., Dong, Z., Jiang, J.Z., and
Zheng, W. \A magnetic-geared outer-rotor permanentmagnet
brushless machine for wind power generation",
In Industry Applications Conference, 2007. 42nd IAS
Annual Meeting. Conference Record of the 2007 IEEE,
pp. 573-580 (2007).
8. Chau, K.T., Zhang, D., Jiang, J.Z., Liu, C., and
Zhang, Y. \Design of a magnetic-geared outer-rotor
permanent-magnet brushless motor for electric vehicles",
IEEE Transactions on Magnetics, 43, pp. 2504-
2506 (2007).
9. Jian, L., Xu, G., Wu, Y., Cheng, Z., and Song, J.
\A novel power-train using coaxial magnetic gear for
power-split hybrid electric vehicles", In 2011 InternaM.
A. Rahimi et al./Scientia Iranica, Transactions B: Mechanical Engineering 25 (2018) 772{789 783
tional Conference on Electrical Machines and Systems,
ICEMS 2011, Beijing (2011).
10. Atallah, K., Calverley, S.D., and Howe, D. \Design,
analysis and realisation of a high-performance magnetic
gear", IEE Proceedings: Electric Power Applications,
151, pp. 135-143 (2004).
11. Rasmussen, P.O., Mortensen, H.H., Matzen, T.N.,
Jahns, T.M., and Toliyat, H.A. \Motor integrated
permanent magnet gear with a wide torque-speed
range", In 2009 IEEE Energy Conversion Congress
and Exposition, ECCE 2009, San Jose, CA, pp. 1510-
1518 (2009).
12. Evans, D.J. and Zhu, Z.Q. \In
uence of design parameters
on magnetic gear's torque capability", In
2011 IEEE International Electric Machines and Drives
Conference, IEMDC 2011, Niagara Falls, ON, pp.
1403-1408 (2011).
13. Gerber, S. and Wang, R.J. \Evaluation of a prototype
magnetic gear", In Industrial Technology (ICIT), 2013
IEEE International Conference on, pp. 319-324 (2013).
14. Dudley, D., Chief Editor, Gear Handbook, Ed.,
McGraw-Hill Book Co (1962).
15. Jorgensen, F.T., Andersen, T.O., and Rasmussen, P.O.
\Two dimensional model of a permanent magnet spur
gear-A mathematical method used to model a parallel
magnetised magnetic spur gear", In Conference Record
- IAS Annual Meeting (IEEE Industry Applications
Society), Kowloon, Hong Kong, pp. 261-265 (2005).
16. Li, Y., Xing, J.W., Lu, Y.P., and Yin, Z.J. \Torque
analysis of a novel non-contact permanent variable
transmission", IEEE Transactions on Magnetics, 47,
pp. 4465-4468 (2011).
17. Shah, L., Cruden, A., and Williams, B.W. \A magnetic
gear box for application with a contra-rotating
tidal turbine", In Proceedings of the International
Conference on Power Electronics and Drive Systems,
Bangkok, pp. 989-993 (2007).
18. Jian, L., Chau, K.T., Gong, Y., Jiang, J.Z., Yu,
C., and Li, W. \Comparison of coaxial magnetic
gears with di erent topologies", IEEE Transactions on
Magnetics, 45, pp. 4526-4529 (2009).
19. Li, X., Chau, K.T., Cheng, M., Hua, W., and Du, Y.
\An improved coaxial magnetic gear using
ux focusing",
In 2011 International Conference on Electrical
Machines and Systems, ICEMS 2011, Beijing (2011).
20. Fukuoka, M., Nakamura, K., and Ichinokura, O. \A
method for optimizing the design of SPM type magnetic
gear based on reluctance network analysis", In
Electrical Machines (ICEM), 2012 XXth International
Conference on, pp. 30-35 (2012).