Transient orbital analysis of rotor with mixed eccentricity for permanent magnet synchronous motor of electric vehicles

Abstract

The unbalanced magnetic pull (UMP) induced by rotor eccentricity has been studied for permanent magnet synchronous motors (PMSMs); however, the electromagnetic excitation only considers the magnetic field of the rotor. Meanwhile, the harmonics of UMPs induced by electromagnetic field interaction of stator and rotor, also its influence on the critical speed and the transient vibration of rotor have not been fully investigated. Through the analysis of magnetomotive force (MMF) harmonics of stator, rotor, and air-gap permeances with rotor static and dynamic eccentricity, the analytical expressions of UMP harmonics for rotor mixed eccentricity are derived with the Maxwell stress tensor (MST) method in this study. The impact of the typical harmonics of UMPs on the critical speeds and transient whirl orbits of rotor system is studied through rotordynamic simulation. It is found that more critical speeds are generated with harmonics of UMPs, and the transient vibration responses are different for two types of eccentricities in the axial direction. This study contributes to understand critical speeds of PMSMs and detection of different types of rotor eccentricities.

Keywords

electromagnetic forces mixed eccentricity of rotor permanent magnet synchronous motors unbalanced magnetic pull electromagnetic vibration rotordynamic

Get full access to this article

View all access options for this article.

References

Alam

Abbaszadeh

(2016) Magnetic field analysis in eccentric surface-mounted permanent-magnet motors using an improved conformal mapping method. IEEE Transactions on Energy Conversion 31(1): 333–344. https://doi.org/10.1109/tec.2015.2479562

Bauer

Werner

(2016) Method to detect the critical bending speed of an induction motor by using static rotor eccentricity for deriving the roller bearing stiffness. Proceedings of 11th International Conference on Vibration in Rotating Machinery, VIRM 11. Manchester, UK: Institution of Mechanical Engineers.

Chen

Huang

, et al. (2019) Evaluation of the harmonics in permanent-magnet synchronous traction motor with low switching frequency power supply. 22nd International Conference on Electrical Machines and Systems (ICEMS). Harbin, China: IEEE. https://doi.org/10.1109/ICEMS.2019.8922206

Ellison

Yang

(1971) Effects of rotor eccentricity on Acoustic noise from induction machines. Proceedings of the Institution of Electrical Engineers 118(1): 174–184. https://doi.org/10.1049/piee.1971.0028

Genta

(2005) Dynamic of Rotating Systems. Torino: Springer.

Guo

Bai

(2021) Coupling effect of unbalanced magnetic pull and ball bearing on nonlinear vibration of motor rotor system. Journal of Vibration and Control 28(5): 665–676. https://doi.org/10.1177/1077546320981320

Guo

Cai

(2023) Prediction of electromagnetic vibration with simulated transfer function for interior permanent magnet synchronous motor. IEEE Transactions on Energy Conversion 38(4): 2584–2595. https://doi.org/10.1109/tec.2023.3292061

Guo

Chu

Chen

(2002) The unbalanced magnetic pull and its effects on vibration in a three-phase generator with eccentric rotor. Journal of Sound and Vibration 254(2): 297–312. https://doi.org/10.1006/jsvi.2001.4088

Wei

Chen

, et al. (2019) Vibration study of permanent magnet synchronous motor base on static eccentricity model. 22nd International Conference on Electrical Machines and Systems (ICEMS). Harbin, China: IEEE. https://doi.org/10.1109/ICEMS.2019.8922162

10.

Ito

Takeuchi

Kotsugai

, et al. (2021) A study on asymmetry of electromagnetic force modes of permanent magnet synchronous motors with rotor eccentricity. IEEE Transactions on Magnetics 57(2): 1–6. https://doi.org/10.1109/tmag.2020.3027816

11.

Lin

Zuo

Deng

(2017) Impact of rotor eccentricity on electromagnetic vibration and noise of permanent magnet synchronous motor. Journal of Vibroengineering 20(2): 923–935. https://doi.org/10.21595/jve.2017.18436

12.

Mehrgou

Garcia de Madinabeitia

Graf

, et al. (2018) NVH aspects of electric drives-integration of electric machine, gearbox and inverter. SAE Technical Paper 1: 1556. https://doi.org/10.4271/2018-01-1556

13.

Pile

Devillers

Le Besnerais

(2018) Comparison of main magnetic force computation method for noise and vibration assessment in electrical machines. IEEE Transactions on Magnetics 54(7): 1–13. https://doi.org/10.1109/tmag.2018.2828388

14.

Santos

Luersen

Bavastri

(2013) Experimental evaluation of numerical models to represent the stiffness of laminated rotor cores in electrical machines. Journal of Engineering Science & Technology 8(4): 457–471.

15.

Tenhunen

(2001) Finite element calculation of unbalanced magnetic pull and circulating current between parallel windings in induction motor with non-uniform eccentric rotor. Electromotion'01. Bologna, Italy.

16.

Werhoff

Jacobs

Drichel

(2018) Noise, vibration and harshness validation methodology for complex elastic multibody simulation models: with application to an electrified drive train. Journal of Vibration and Control 25(2): 243–254.

17.

Zhou

Bao

, et al. (2018) Calculation and analysis of unbalanced magnetic pulls of different stator winding setups in static eccentric induction motor. Chinese Physics B 27(8): 088401. https://doi.org/10.1088/1674-1056/27/8/088401