Rotational Magnetic Field Calculation of Electrical Motors by Incorporating a Modified Anisotropic Vector Hysteresis Model

An improved Preisach-type vector hysteresis model of inversed fashion considering magnetic anisotropy for nonoriented (NO) steel sheet is proposed in this paper. By introducing new mathematical expression and identification method for the anisotropy vector Everett function, tedious measurement of scalar magnetic properties along different cutting directions is circumvented and high order truncated Fourier decomposition required by the traditional method is evaded. The validity of the proposed hysteresis model is investigated through comparisons between modeling and experimental results of NO electrical steel under both alternating and rotational magnetization. Moreover, the field evolution in the iron core of a permanent magnet synchronous machine (PMSM) is solved by finite-element method (FEM), where the nonlinearity of magnetic material is characterized by the introduced hysteresis model. The numerical solution shows good consistency with measured data detected by the local sensors placed on the prototype, indicating the modeling applicability and effectiveness.