Estimation of Losses and Efficiency of Double-stator Switched Flux Permanent Magnet Machines

Authors

  • C. C. Awah Department of Electrical and Electronics Engineering, Michael Okpara University of Agriculture, Umudike. PMB 7267 Umuahia, Abia State
  • O. I. Okoro Department of Electrical and Electronic Engineering, Michael Okpara University of Agriculture, Umudike
  • A. J. Onah Department of Electrical and Electronic Engineering, Michael Okpara University of Agriculture, Umudike
  • G. C. Diyoke

Keywords:

Eddy current loss, Efficiency, iron losses, Rotor pole, Stator teeth numbers

Abstract

Losses such as rotor iron and stator iron losses, magnet eddy current loss, as well as efficiency of a double stator permanent magnet machine having varying rotor pole numbers is estimated and presented in this study.  This current investigation would be vital for electrical machine designers in quantifying the amount of losses in the various sections of a given double stator electric machine and as well provide better insight on resulting output efficiency of the machine. Time-stepping finite element analysis (TS-FEA) procedure is adopted in the calculations using ANSYS-MAXWELL simulation software. The compared machines having the same stator teeth/pole number (Ps) and different rotor pole (Pr) numbers are designated as: 6Ps/10Pr, 6Ps/11Pr, 6Ps/13Pr and 6Ps/14Pr. The predicted total loss values at rated current and operating base speed is 13.02 Watts, 13.13 Watts, 13.539 Watts, 13.537 Watts, from the 6Ps/10Pr, 6Ps/11Pr, 6Ps/13Pr and 6Ps/14Pr machine types, respectively. The corresponding efficiency of the machine types at rated working conditions is: 81.76%, 88.17%, 86.95% and 78.61%, respectively. The results show that magnitude of losses in a given machine would largely depend upon factors such as number of rotor poles and hence, the machine’s operating speed, electric loading and angular rotor position of the machine, etc. It is also found that the number of loss waveform cycles (Nc) in an electric revolution of the investigated machine would depend upon its stator and rotor arrangements. The most performing compared machine types are the ones that have 11- and 13-rotor pole numbers, while the least amount of efficiency is obtained from the machine type that has 14-rotor pole number. Above all, the 6Ps/10Pr and 6Ps/14Pr are characterized with high amount of pulsations or ripples and this is detrimental to the overall performance of the machines.

References

Alberti, L.; E. Fornasiero and N. Bianchi. (2012). Impact of the rotor yoke geometry on rotor losses in permanent-magnet machines. IEEE Transactions on Industry Applications, 48(1): 98–105.

Al-Timimy, A.; P. Giangrande; M. Degano, Z. Xu, M. Galea, C. Gerada, G.L. Calzo, H. Zhang and L. Xia (2018). Design and losses analysis of a high power density machine for flooded pump applications. IEEE Transactions on Industry Applications, 54(4): 3260–3270.

Awah, C.C. and Okoro, O.I. (2019). Fault-tolerant capability and torque-speed measurements of permanent magnet brushless AC machines. Nigerian Journal of Technological Development, 16(4): 191–198.

Castagnaro, E.; G. Bacco and N. Bianchi. (2019). Impact of geometry on the rotor iron losses in synchronous reluctance motors. IEEE Transactions on Industry Applications, 55(6): 5865–5872.

Chen, Q.; D. Liang; S. Jia, Q. Ze and Y. Liu (2020). Analysis of winding MMF and loss for axial flux PMSM with FSCW layout and YASA topology. IEEE Transactions on Industry Applications, 56(3): 2622–2635.

Cheng, X.; W. Xu; G. Du, G. Zeng and J. Zhu. (2019). Novel rotors with low eddy current loss for high speed permanent magnet machines. CES Transactions on Electrical Machines and Systems, 3(2): 187–194.

Fang, S.; H. Liu; H. Wang, H. Yang and H. Lin. (2019). High power density PMSM with lightweight structure and high-performance soft magnetic alloy core. IEEE Transactions on Applied Superconductivity, 29(2): 1–5.

Tang, C.; W.L. Soong; T.M. Jahns and N. Ertugrul. (2015). Analysis of iron loss in interior PM machines with distributed windings under deep field weakening. IEEE Transactions on Industry Applications, 51(5): 3761–3772.

Thomas, A.S.; Z.Q. Zhu and G.J. Li. (2014). Thermal modelling of switched flux permanent magnet machines. Paper presented at IEEE International Conference on Electrical Machines (ICEM2014), Berlin, Germany, 2212–2217.

Li, H. and Zhu, Z.Q. (2019). Influence of adjacent teeth magnet polarities on the performance of flux reversal permanent magnet machine, IEEE Transactions on Industry Applications, 55(1): 354–365.

Li, Q.; T. Fan and X. Wen. (2017). Characterization of iron loss for integral-slot interior permanent magnet synchronous machine during flux weakening. IEEE Transactions on Magnetics, 53(5): 1–8.

Xue, L.; L. Luo and J. Pu. (2019). Eddy current calculation of a high-speed slotted machine with halbach magnetization at no-load condition. IEEE Transactions on Magnetics, 55(11): 1–10.

Yu, Y.; D. Liang; Z. Liang and Q. Ze. (2018). Calculation for stator loss of high-speed permanent magnet synchronous machine in torque-speed envelope and restraint approach for circulating current in windings. CES Transactions on Electrical Machines and Systems, 2(2): 211–219.

Zahr, H.; E. Semail and F. Scuiller. (2014). Five-phase version of 12slots/8poles three-phase synchronous machine for marine-propulsion. Paper presented at IEEE Vehicle Power and Propulsion Conference (VPPC), Coimbra, Portugal, pp. 1–6, USA: IEEE.

Zhang, Z.; H. Liu; T. Song, Q. Zhang, W. Hu and W. Liu. (2019). Performance evaluation of a 60kW IPM motor for medium commercial EV traction application. CES Transactions on Electrical Machines and Systems, 3(2): 195–203.

Zhu, Z.Q.; Y. Pang; D. Howe, S. Iwasaki, R. Deodhar and A. Pride. (2005). Analysis of Electromagnetic performance of flux-switching permanent-magnet machines by nonlinear adaptive lumped parameter magnetic circuit model. IEEE Transactions on Magnetics, 41(11): 4277–4287.

Downloads

Published

2022-06-30

Issue

Vol. 19 No. 2 (2022)

Section

Articles

License

Copyright (c) 2022 Nigerian Journal of Technological Development

Creative Commons License

This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.

In accordance with the Copyright Act of 1976, which became effective January 1, 1978, the following statement signed by each author must accompany the manuscript submitted: "I, the undersigned author, transfer all copyright ownership of the manuscript referenced above to the Nigerian Journal of Technological Development, in the event the work is published. I warrant that the article is original, does not infringe upon any copyright or other proprietary right of any third party, is not under consideration by another journal, and has not been published previously. I have reviewed and approve the submitted version of the manuscript and agree to its publication in the Nigerian Journal of Technological Development." A copyright transfer form should be downloaded from the NJTD Website ( http://njtd.com.ng/index.php/njtd). Author(s) will be consulted, whenever possible, regarding republication of material. All authors must have access to the data presented and the authors and sponsor (if applicable) must agree to share original data with the editor if requested.