Optimising the flux barriers of interior permanent magnet machine for noise reduction under certain load conditions

Abstract

This study proposes a method to reduce the electromagnetic noise of a double-layer interior permanent magnet synchronous motor (DIPMSM) by optimising the flux barrier. First, a noise prediction model of the 36-slot/8-pole DIPMSM is established by finite element (FE). According to the simulation results, the noise of the motor is the loudest at 5000 rpm, especially with a noise component of 3333.3 Hz. From the results of modal analysis, it can be concluded that the four-order radial force with a frequency of 3333.3 Hz resonates with the stator, resulting in the loudest noise. Then, the source of the radial force that causes the loudest noise is analysed, and it can be found that the 9th and 11th harmonics of rotor magnetic motive force have the greatest contribution to the force. By optimising the rotor, the radial force contributed by the 9th and 11th harmonics is weakened, thereby reducing the noise caused by these harmonics. Finally, the electromagnetic performance and noise of the optimised motor are checked by FE. Compared with the initial rotor, the torque ripple is reduced by 26.79%, and noise is reduced by 5.542 dB. The noise test on the prototype verifies the accuracy of the noise prediction model.This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made.

Fast Calculation of Electromagnetic Forces in IPMSMs Under PWM VSI Supply Based on Small-Signal Time-Harmonic Finite Element Method

“…(1) The phase resistance makes the assumption that the voltage is proportional to the flux density no longer true when the frequency is low. (2) The PWM flux density harmonics may also contribute to the saturation in the SSTs, which is assumed to be only determined by the fundamental current with the FDRTM. (3) The Phase angle difference between the highfrequency flux densities calculated with the proposed method and the traditional TSFEA shown in Table II may also cause the error in the calculated electromagnetic force.…”

“…NTERIOR permanent magnet synchronous machines (IPMSMs) are widely applied in electrical vehicles and industries in modern times [1]. The accurate modeling of the electromagnetic noise and vibration characteristics of IPMSMs is essential for their optimal design, which requires accurate electromagnetic force calculations on the inner surfaces of stators [2]- [10]. Because of the nonlinearity of IPMSMs, finite element analysis (FEA) is the most widely used methods for the accurate force calculation, which is however time-consuming [2]- [6].…”

“…The accurate modeling of the electromagnetic noise and vibration characteristics of IPMSMs is essential for their optimal design, which requires accurate electromagnetic force calculations on the inner surfaces of stators [2]- [10]. Because of the nonlinearity of IPMSMs, finite element analysis (FEA) is the most widely used methods for the accurate force calculation, which is however time-consuming [2]- [6]. Especially, when the pulse width modulation (PWM) effects are considered, fine steps are needed to distinguish highfrequency components if the traditional time-stepping FEA (TSFEA) is used, disregarding current sources contained highfrequency harmonic currents (HFHCs) or PWM voltages are used as the input for the transient calculation [7]- [11].…”

Sensitivity Analysis of the Design Parameters of Permanent Magnet Synchronous Motors for Vibration Reduction

“…Regarding the rotor, the most typical strategies are to modify the shape [8][9][10][11] and the height [12,13] of the permanent magnets. Some authors also vary the magnetization direction of the magnets [12] or include different notch geometries to the rotor [14][15][16][17].…”

The Analysis of Permanent Magnet Vernier Synchronous Machine Vibration and Noise

“…Optimizing the design of the magnetic isolation bridge for the built-in permanent magnet machine can reduce low-order radial electromagnetic forces and vibration noise. [12,13]. A mathematical model for analyzing the radial electromagnetic force density of surface-mounted permanent magnet machines can be established to obtain the amplitude frequency and order and further determine the resonance situation, revealing the influence of PMSM parameters on vibration noise [14,15].…”