Analytical Open-Circuit Magnetic Field Distribution of Slotless Brushless Permanent-Magnet Machines With Rotor Eccentricity

• Published in: IEEE transactions on magnetics Vol. 47; no. 12; pp. 4791 - 4808
• Main Authors: Rahideh, A., Korakianitis, T.
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01.12.2011; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Brushless motors; Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; External rotor; Halbach; internal rotor; Magnetic flux; Magnetism; Magnetization; Materials science; modeling; Other topics in materials science; permanent magnet; Permanent magnet machines; Physics; rotor eccentricity; Rotors; Stator windings; permanent magnet; Open circuit; modeling; Magnetization; Eccentricity; Rotors; Magnetic field effects; Permanent magnets; Machine; rotor eccentricity; Halbach; External rotor; internal rotor; Modelling; Magnetic fields; Magnetic properties
• ISSN: 0018-9464; 1941-0069
• DOI: 10.1109/TMAG.2011.2159987

Analytical expressions for the no-load magnetic field distribution of slotless brushless permanent-magnet (PM) machines with static, dynamic, and mixed rotor eccentricities are presented. The proposed analytical expressions can be used for slotless brushless PM machines with any radius-independent magnetization pattern. The analytical expressions and the results for six different magnetization patterns are presented. Based on the analytical magnetic field distribution, the line and phase back-electromotive force waveforms, local traction components and unbalanced magnetic forces are obtained. The analytical results are compared with those from finite-element analyses to validate the derived expressions.