Analytical Modeling of PM Electrical Machines With Eccentric Surface-Inset Halbach Magnets

In this article, a linear analytical model has been proposed for solving and optimizing the magnetic fields in brushless permanent magnet (PM) electrical machines having eccentric surface-inset magnets. Using a subdomain model with an equivalently split method, on the basis of a linear superposition, the magnetic fields have been analytically obtained and optimized in the PM machines having the assumed linear materials with proposed eccentric surface-inset Halbach magnets. Moreover, the induced phase electromotive force and instantaneous electromagnetic torque have been also derived. Compared with the conventional and concentric Halbach surface-inset models, the optimized eccentric Halbach model exhibits good performances with the equal magnet volume. The prediction results of the linear analytical model are coincided with finite element analysis (FEA).