Stator vibration and acoustic noise analysis of FSPM for a low-noise design

Noise and vibration in FSPM machines is one of the issues where improvement is needed, especially in topologies that are of segmented stator type. The stator mode frequencies and intensity of acoustic noise generated by magnetic radial force is related to the geometry, configuration and material properties. A method for estimating mode frequencies for segmented stator is proposed. A new pole shaping method is proposed to reduce the effect of undesirable mode frequencies on noise and vibration. The mode frequencies have been calculated using analytical models and verified using structural FEA. A low-noise FSPM design technique is proposed based on pole shaping and structural analysis. The effect of the proposed method on electromagnetic performance of the machine has also been investigated. A prototype FSPM is fabricated and tested based on the proposed design.