Establishing an accurate stator system modal analysis model is of great significance for the vibration and noise analysis of the motor, scholars still have some controversy about how to set the material properties of the stator core and winding in modal analysis. Firstly, the equivalent models of stator core and winding were analyzed, the initial value of equivalent material parameters was determined. Secondly, the finite element models were used to analyze the influence of the equivalent material parameters on the natural frequency, a correction method of equivalent material parameters was proposed. Thirdly, the modal of stator core and the stator core with winding were tested by the moving force method. The finite element analysis results are consistent with the modal test results. Some influence laws of equivalent material parameters on natural frequency are obtained. The proposed correction method of equivalent material parameters helps to quickly determine the equivalent material properties of the stator core and windings. Setting the properties of the stator core and the winding material to the orthotropic materials can ensure the accuracy of the modal analysis.

An accurate prediction of modal characteristics of motor stator is essential in order to design a low vibration motor and to operate it quietly. Scholars have done a lot of research on the modal analysis of stator core and winding. However, there are few papers for the 0th-order mode shape and frequency of the stator system. This paper aims to propose a new stator system analysis model, which can effectively analyze the 0th-order mode and improve the model calculation efficiency. Firstly, the modal of stator core and stator core-winding system were analyzed theoretically. Secondly, four stator system finite element analysis models were established. The modal analysis of the stator core and stator core-winding system were carried out using the four models. The validity and computational efficiency of the four models of the stator core and stator core-winding system were compared. A new stator system analysis model was proposed. Thirdly, the modal tests of the stator core and stator core-winding system were carried out by hammering method, and the validity of the finite element analysis model was verified. Compared with the traditional model, the newly proposed model can analyze the 0th-order mode more effectively and improve the computational efficiency.

The energy crisis and environmental concerns worldwide have helped usher in the age of electric vehicles (EVs) and hybrid EVs (HEVs). The interior permanent magnet motors (IPMMs) are widely used in these vehicles. The analysis of the armature reaction field is the most critical issue in the study of IPMMs since it determines the characters of torque, efficiency, vibration, and the radiated acoustic noise. This paper provides a calculation method of the armature reaction magnetic field (ARMF) of an IPMM. First, the formulas of ARMF without magnetic barrier are derived. Second, the relative permeance function of an IPMM is calculated. Third, the analytical solution of the ARMF of an IPMM is derived by applying the armature reaction magnetic field with unsaturated rotor multiplied by relative permeance function. Finally, several results of comparisons between the calculation method proposed in this paper and the finite element method are presented. Based on the calculation method proposed in this paper, the magnetic barrier’s influence on the ARMF is studied. The spatial harmonic orders and time harmonic orders of the ARMF of IPMM are revealed respectively.

Due to the increasing energy crisis and environmental pollution, the development of drive motors for new energy vehicles (NEVs) has become the focus of popular attention. To improve the sine of the air-gap flux density and flux regulation capacity of drive motors, a new hybrid excitation synchronous motor (HESM) has been proposed. The HESM adopts a salient pole rotor with built-in dual-V permanent magnets (PMs), non-arc pole shoes and excitation windings. The fundamental topology, operating principle and analytical model for a magnetic field are presented. In the analytical model, the rotor magnetomotive force (MMF) is derived based on the minimum reluctance principle, and the permeance function considering a non-uniform air-gap is calculated using the magnetic equivalent circuit (MEC) method. Besides, the electromagnetic performance including the air-gap magnetic field and flux regulation capacity is analyzed by the finite element method (FEM). The simulation results of the air-gap magnetic field are consistent with the analytical results. The experiment and simulation results of the performance show that the flux waveform is sinusoidal-shaped and the air-gap flux can be adjusted effectively by changing the excitation current. This study provides design methods and theoretical analysis references for this type of HESM.