@ARTICLE{Pawel_Witczak_Modal-frequency_2014, author={Pawel Witczak and Kubiak, Witold and Lefik, Marcin and Szulakowski, Jacek}, volume={vol. 63}, number={No 1 March}, journal={Archives of Electrical Engineering}, pages={29-46}, howpublished={online}, year={2014}, publisher={Polish Academy of Sciences}, abstract={The classic relationships concerning the harmonic content in the air gap field of three-phase machines are presented in form of series of rotating waves. The same approach is applied to modeling of permanent magnet motors with fractional phase windings. All main reasons of non-sinusoidal shape of flux density distribution, namely, magnets’ shape and their placement, slotting, magnetic saturation and eccentricity are also related to their counterparts in modal-frequency spectrum. The Fourier 2D spectrum of time-stepping finite element solution is confronted with results of measurements, with special attention paid to accuracy of both methods.}, type={Artykuły / Articles}, title={Modal-frequency spectrum of magnetic flux density in air gap of permanent magnet motor}, URL={http://journals.pan.pl/Content/84885/PDF/03_paper.pdf}, doi={10.2478/aee-2014-0003}, keywords={electromagnetic fields, waves permanent magnet machines, air gap magnetic flux, spectral analysis, finite element method}, }