Effect of magnet/slot combination on triple-frequency magnetic force and vibration of permanent magnet motors

Magnetically induced rotor vibration in dual-stator permanent magnet motors

“…Given the structural and force complexes, the scope is limited to the lower speed motors such as the direct drive one. Main findings are obtained by analytical derivation and verified by comparison with those from superposition method [12,14] and FEM. Fig.…”

“…The natural frequencies of the three modes can be obtained by using Eqs. (13) and (14). It needs to be noted that some of these results, especially the rigid and elastic vibration for n¼ 0 and 71, are scattered in the literature, such as a recent paper [35].…”

“…It needs to be noted that some of these results, especially the rigid and elastic vibration for n¼ 0 and 71, are scattered in the literature, such as a recent paper [35]. Whether they are excited or not depends on the forcing terms on the right hand side, like those in motor, gear and other cyclically symmetric power-transmission systems [11,12,14,24,27]. …”

“…One can have the relationships between basic parameters, including the magnet/slot combination, force's frequency and amplitude, natural frequencies, the relative position and other parameters of interest, and the harmonic forced vibration. Please note that the magnet/slot combination and relative position determine the phases of the forcing terms on the right hand side of the governing equations, affecting the final response via force cancel or add, just like those in single-stator motors [14].…”

Influence of Slots and Rotor Poles Combinations on Noise and Vibrations of Magnetic Origins in `U'-Core Flux-Switching Permanent Magnet Machines

“…Past frequency corresponding to vibrational mode 4, the 12s11rp configuration is the less noisy one, followed by the 12s13rp one. However, they can cause translational vibration at frequency corresponding to mode 1 [43]. Though, as shown in Fig.…”