Jawad Faiz, Tohid Asefi, Mohammad Azeem Khan

DOI Number
First page
Last page


This article addresses dual rotor axial flux Ferrite permanent magnet (PM)  generator,  as an alternative to a surface mounted and  spoke types Nd-Fe-B generator which have concentrated windings. The performance parameters of all generators, particularly the efficiency, are identical. The design objective function is the generators mass minimization using a population-based algorithm. To predict the performance of yhe generators a finite element (FE) technique is applied. Besides, the aims of the design include minimizing cogging torque, examining different rotor pole topologies and different pole arc to pole pitch ratios. Three-dimensional FE technique is employed. It is shown that the surface mounted Ferrite generator topology cannot develop the rated torque and also has high torque ripple. In addition, it is heavier than the spoke type generator. Furthermore, it is indicated that the spoke type Ferrite PM generator has favorable performance and could be an alternative to rare-earth PM generators, particularly in wind energy applications. Finally, the performance of the designed generators is experimentally verified.


Axial flux, permanent magnet generator, dual rotor, finite element analysis, wind turbines, cogging torque, population-based algorithm

Full Text:



J. Faiz, T. Asefi and M. A. Khan, "Design of Axial Flux Ferrite Permanent Magnet Synchronous Generator”, In Proceedings of the 14th International Conference on Applied Electromagnetics (ПЕС 2019), August 26 - 28, 2019, Niš, Serbia.

T. Asefi, J. Faiz, and M. A. Khan. "Design of Dual Rotor Axial Flux Permanent Magnet Generators with Ferrite and Rare-Earth Magnets", In Proceedings of the IEEE 18th International Power Electronics and Motion Control Conference (PEMC), Budapest, Hungry, 2018.

M. Dahlgren, H. Frank, M. Leijon and F. Owman, "Wind Former; Wind Power Goes Large Scale," ABB Rev, 3:31-37.J. , 2000.

K. H. Kim, H. I. Park, S. M. Jang, D. J. You and J. Y. Choi, "Comparative Study of Electromagnetic Performance of High-Speed Synchronous Motors With Rare-Earth and Ferrite Permanent Magnets," IEEE Trans. Magn., vol. 52, no. 7, pp. 1–4, Jul. 2016.

S. Chung, S. H. Moon, D. J. Kim and J. M. Kim, "Development of a 20-Pole–24-Slot SPMSM With Consequent Pole Rotor for In-Wheel Direct Drive," IEEE Trans. Ind. Electron, vol. 63, no. 1, pp. 302–309, Jan. 2016.

M. Kimiabeigi, J. D. Widmer, R. Long, Y. Gao, J. Goss, R. Martin, T. Lisle, J. M. Soler Vizan, A. Michaelides and B. Mecrow, "High-Performance Low-Cost Electric Motor for Electric Vehicles Using Ferrite Magnets," IEEE Trans. Ind. Electron., vol. 63, no. 1, pp. 113–122, Jan. 2016.

I. Petrov and J. Pyrhönen, "Performance of Low-Cost Permanent Magnet Material in PM Synchronous Machines," IEEE Trans. Ind Electron., vol. 60, no. 6, pp. 2131–2138, June 2013.

Y. Chen, P. Pillay and M. Khan, "PM Wind Generator Comparison of Different Topologies," IEEE Trans. Ind Appl., vol. 41, no. 6, pp. 1619–1626, Nov. 2005.

M. A. Khan, P. Pillay and K. Visser, "On Adapting a Small PM Wind Generator for a Multi-Blade, High Solidity Wind Turbine," IEEE Trans. Energy Convers., vol. 20, no. 3, pp. 685–692, Sep. 2005.

H. Jagau, M. A. Khan and P. S. Barendse, "Design of a Sustainable Wind Generator System using Redundant Materials," IEEE Trans. Ind. Appl., vol. 48, no. 6, pp. 1827–1837, Nov./Dec. 2012.

J. Wanjiku, H. Jagau and M. A. Khan, "A Simple Core Structure for Small Axial-Flux PMSGs," in IEEE International Electric Machines & Drives Conference (IEMDC), Niagara Falls, May 2011.

J. R. Hendershot and T. J. E. Miller, "Design of Brushless Permanent-Magnet Motor"s, USA: Oxford University Press, 1995.

F. Gieras, R. Wang and M. J. Kamper, "Axial Flux Permanent Magnet Brushless Machines", 2nd ed, Springer, 2008.

W. Zhao, T. A. Lipo and B. Kwon, "Comparative Study on Novel Dual Stator Radial Flux and Axial Flux Permanent Magnet Motors With Ferrite Magnets for Traction Application," IEEE Trans. Mag., vol. 50, no. 11, pp. 1–4, Nov, 2014.

H. Tiegna, A. Bellara, Y. Amara and G. Barakat, "Analytical Modeling of the Open-Circuit Magnetic Field in Axial Flux Permanent-Magnet Machines With Semi-Closed Slots," IEEE Trans. on Mag., vol. 48, no. 3, pp. 1212–1226, Sep. 2012.

D. Ishak, Z. Q. Zhu and D. Howe, "Performance Variation of Ferrite Magnet PMBLDC Motor With Temperature," IEEE Trans. Magn., vol. 51, no. 12, p. 95–103, Dec. 2015.

P. Zhang, G. Y. Sizov, J. He, D. M. Ionel and N. A. O. Demerdash, "Calculation of Magnet Losses in Concentrated-Winding Permanent-Magnet Synchronous Machines Using a Computationally Efficient Finite-Element Method," IEEE Trans. Ind. Appl., vol. 49, no. 6, pp. 1495–1504, Nov./Dec. 2013.

J. G. Wanjiku, M. Khan, P. Barendse and P. Pillay, "Influence of Slot Openings and Tooth Profile on Cogging Torque in Axial-Flux PM Machines," IEEE Trans. Ind. Electron., vol. 62, no. 12, pp. 7578–7589, Dec. 2015.


  • There are currently no refbacks.

ISSN: 0353-3670 (Print)

ISSN: 2217-5997 (Online)

COBISS.SR-ID 12826626