Title :
Analytical Open-Circuit Magnetic Field Distribution of Slotless Brushless Permanent-Magnet Machines With Rotor Eccentricity
Author :
Rahideh, A. ; Korakianitis, T.
Author_Institution :
Sch. of Electr. & Electron. Eng., Shiraz Univ. of Technol., Shiraz, Iran
Abstract :
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.
Keywords :
brushless DC motors; electric potential; finite element analysis; magnetisation; permanent magnet motors; permanent magnets; rotors; waveform analysis; analytical open-circuit magnetic field distribution; dc motors; dynamic rotor eccentricity; finite-element analysis; line back-electromotive force waveforms; local traction components; mixed rotor eccentricity; phase back-electromotive force waveforms; radius-independent magnetization; slotless brushless permanent-magnet machines; static rotor eccentricity; unbalanced magnetic forces; Brushless motors; Magnetic flux; Magnetization; Permanent magnet machines; Rotors; Stator windings; External rotor; Halbach; internal rotor; magnetization; modeling; permanent magnet; rotor eccentricity;
Journal_Title :
Magnetics, IEEE Transactions on
DOI :
10.1109/TMAG.2011.2159987
