Title :
Induced voltage harmonic reduction of PM cylindrical machines
Author :
De La Ree, J. ; Boules, Nady
Author_Institution :
Virginia Polytech. Inst. & State Univ., Blacksburg, VA, USA
Abstract :
Typically, permanent magnet (PM) machines with surface-mounted magnets have trapezoidal induced voltage waveforms with high harmonic content that can adversely affect torque pulsations, noise, and efficiency. A simple methodology for reducing these harmonics by selecting the appropriate magnet shape and dimensions has been introduced previously by the authors (see IEEE Proc. PES 1989 Summer Mtg.). For illustrative purposes, however, the method used a simplified analytical model of the magnetic circuit, ignoring important factors such as curvature and magnet leakage. The authors presently apply the proposed methodology to cylindrical machines using a more precise model. The results, showing the potential for reducing induced-voltage harmonics by using a double-magnet per pole configuration, have been verified by comparison with results obtained from finite element analysis
Keywords :
finite element analysis; harmonics; machine theory; magnetic circuits; permanent magnet machines; cylindrical machines; efficiency; finite element analysis; machine theory; magnetic circuit; noise; permanent magnet machines, FEM; torque pulsations; trapezoidal induced voltage waveforms; Adders; Analytical models; Circuit noise; Magnetic noise; Noise shaping; Permanent magnets; Shape; Surface waves; Torque; Voltage;
Journal_Title :
Industry Applications, IEEE Transactions on