Fourier decomposition of segmented magnets with radial magnetization in surface-mounted PM machines

Tow Leong Tiang 1 , Dahaman Ishak 2 , and Chee Peng Lim 3
  • 1 Universiti Malaysia Perlis, Pauh Putra Campus, , 02600, Arau, Malaysia
  • 2 Universiti Sains Malaysia, Engineering Campus, , 14300, Nibong Tebal, Malaysia
  • 3 Deakin University, Geelong Waurn Ponds Campus, , 3220, Geelong, Australia

Abstract

This paper presents a generic field model of radial magnetization (RM) pattern produced by multiple segmented magnets per rotor pole in surface-mounted permanent magnet (PM) machines. The magnetization vectors from either odd- or even-number of magnet blocks per pole are described. Fourier decomposition is first employed to derive the field model, and later integrated with the exact 2D analytical subdomain method to predict the magnetic field distributions and other motor global quantities. For the assessment purpose, a 12-slot/8-pole surface-mounted PM motor with two segmented magnets per pole is investigated by using the proposed field model. The electromagnetic performances of the PM machines are intensively predicted by the proposed magnet field model which include the magnetic field distributions, airgap flux density, phase back-EMF, cogging torque, and output torque during either open-circuit or on-load operating conditions. The analytical results are evaluated and compared with those obtained from both 2D and 3D finite element analyses (FEA) where an excellent agreement has been achieved.

If the inline PDF is not rendering correctly, you can download the PDF file here.

  • [1] R. Lateb, N. Takorabet and F. Meibody-Tabar, “Effect of Magnet Segmentation on the Cogging Torque Surface-Mounted Permanent-Magnet Motors”, IEEE Trans. Magn., vol. 42, pp. 442–445, 2006.

  • [2] L. J. Wu, Z. Q. Zhu, D. Staton, M. Popescu and D. Hawkins, “Analytical Prediction of Electromagnetic Performance of Surface-Mounted PM Machines based on Subdomain Model Accounting for Tooth-Tips”, IET Electric Power Applications, vol. 5, pp. 597–609, 2011.

  • [3] M. Ashabani and Y. A. R. I. Mohamed, “Multiobjective Shape Optimization of Segmented Pole Permanent-Magnet Synchronous Machines with Improved Torque Characteristics”, IEEE Trans. Magn., vol. 47, pp. 795–804, 2011.

  • [4] T. L. Tiang, D. Ishak, C. P. Lim and M. R. Mohamed, “Analytical Method using Virtual PM Blocks to Represent Magnet Segmentations Surface-Mounted PM Synchronous Machines”, Progress Electromagnetics Research B (PIERB), vol. 76, pp. 23–36, 2017.

  • [5] Z. Q. Zhu and D. Howe, “Analytical Prediction of the Cogging Torque Radial-Field Permanent Magnet Brushless Motors”, IEEE Trans. Magn. vol. 28, pp. 1371–1374, 1992.

  • [6] F. Dubas and C. Espanet, “Analytical Solution of the Magnetic Field Permanent-Magnet Motors Taking into Account Slotting Effect: No-Load Vector Potential Flux Density Calculation”, IEEE Trans. Magn. vol. 45, pp. 2097–2109, 2009.

  • [7] Y. Shen and Z. Q. Zhu, “General Analytical Model for Calculating Electromagnetic Performance of Permanent Magnet Brush-less Machines Having Segmented Halbach Array”, IET Electrical Systems Transportation, vol. 3, pp. 57–66, 2013.

  • [8] Y. Shen and Z. Q. Zhu, “Analysis of Electromagnetic Performance of Halbach PM Brushless Machines Having Mixed Grade Unequal Height of Magnets”, IEEE Trans. Magn. vol. 49, pp. 1461–1469, 2013.

OPEN ACCESS

Journal + Issues

Search