Volume 67 | Issue 7 | Year 2021 | Article Id. IJMTT-V67I7P518 | DOI : https://doi.org/10.14445/22315373/IJMTT-V67I7P518
— For Surface Mounted Permanent Magnet (SMPM) generators, it is essential to predict its performance to analyze the magnet’s air gap flux density wave shape. The flux density wave shape is neither a pure sine wave or square wave or combination. This is due to variation of air gap reluctance between stator and permanent magnets. The stator slot openings and the number of slots make the wave shape more complicated. In order to reduce the analysis complexity, approximations are done to the wave shape, and Fourier analysis is used. Instead of usual integration method, the Fourier coefficients, an and bn, are obtained by direct search method optimization. The wave shape with optimized coefficients gave wave shape close to the desired wave shape. Harmonics amplitudes are worked out and compared with initial values. It can be concluded that direct search method can be used for estimating Fourier coefficients for irregular wave shapes
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Mamidi Ramakrishna Rao, "Estimation of Fourier coefficients of flux density for Surface Mounted Permanent Magnet (SMPM) Generators by Direct Search Optimization," International Journal of Mathematics Trends and Technology (IJMTT), vol. 67, no. 7, pp. 150-157, 2021. Crossref, https://doi.org/10.14445/22315373/IJMTT-V67I7P518