Effect of eddy-current loss reduction by magnet segmentation in synchronous motors with concentrated windings

In this study, we investigate the effect of eddy-current loss reduction by magnet segmentation in synchronous motors with concentrated windings. The loss-reduction effects in each harmonic eddy currents in the magnets are analyzed by both the theoretical solution and the 3-D finite element analysis with Fourier transformation. Basic experiments using magnet specimens are carried out in order to support the calculated results. It is clarified that the loss reduction effect varies with the harmonic orders and that the effect depends on the types of the rotors, for example, interior and surface magnet types.

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