Analytical Prediction of Iron-Core Losses in Flux-Modulated Permanent-Magnet Synchronous Machines

In this paper, an analytical approach allowing the prediction of iron-core losses in flux-modulated permanent-magnet synchronous machines. According to the Maxwell-Fourier method (viz., the multi-layer model) and Cauchy's product theorem, the magnetic field distribution is determined in different parts of machine by considering the iron permeability on the basis of solving both Poisson's and Laplace's equations. Next to the dc bias flux density and the minor hysteresis loops, which are taken into account, the Bertotti's model and the flux variation locus are employed to calculate the iron-core losses under load and no-load conditions in post-processing from the magnetic field analytical calculation. Finally, in order to validate the proposed analytical method, the results are verified by the comparison with the finite-element method. The comparisons show good results of the proposed model.