Finite‐element modelization of slotted configurations by means of magnetically anisotropic smooth cores Available to Purchase

The paper presents a methodology in which the slotted regions of electrical machines are replaced by homogeneous regions with anisotropic magnetic permeability. The resulting FEM model is then built and solved in an easy way, because a simplified structure is analyzed, with fixed geometrical characteristics and electrical and magnetic properties depending on the original geometry. The methodology is therefore useful for estimating the machine performances as a function of slot and winding parameters and can be conveniently used at the initial step of the design to perform parametrical analyses and optimizations with uncomplicated procedures for the generation of the FEM model. In order to test the reliability of the method, the FEM results obtained with both the actual configuration and the “smoothed” one must be compared. In the example of application, the proposed methodology is applied to a linear brushless DC motor. The dependence of the accuracy and convergence speed on different “smoothing” strategies is first discussed. Then the obtained results are compared with the ones related to the original slotted configuration. Finally, the correspondence of some important electromagnetic quantities (flux lines distribution, air‐gap flux density and electromagnetic force) is analyzed.