Accurate Modeling of PMSM Considering Orthotropic Material Parameters of Stator System for Vibroacoustic Prediction

An accurate finite element (FE) model is the basis for the numerical prediction of vibration and noise of permanent magnet synchronous motors (PMSMs). This paper provides an equivalent modeling method of PMSMs considering the orthotropic material parameters of the stator system. First, a theoretical analysis of the influence of orthotropic material parameters on modal characteristics is implemented. Subsequently, the influence of orthotropic material parameters on the modal frequency of the stator is analyzed through the FE method. Then, the modal parameters of the stator core and the stator assembly are obtained by modal tests. According to the equivalent FE model and modal parameters, the orthotropic material parameters of the stator system are acquired. Moreover, to save the calculation time and simplify the modal identification process, the influence of windings is taken into account through additional mass and additional stiffness during the modeling process. Considering the real contact situation of each component, a FE model of the whole motor is established and verified by the whole motor modal test. The average error of the symmetric mode of the whole motor is only 1.97%. Finally, the electromagnetic vibration and noise of the motor are calculated based on the equivalent FE model and verified through experimental results. The consistency of the simulation results and the test results illustrates that the established FE model is accurate enough for the vibroacoustic prediction of PMSMs.