On-line detection of rotor eccentricity for PMSMs based on hall-effect field sensor measurements

Rotor eccentricity in permanent magnet synchronous motors (PMSMs) increases unbalanced magnetic pull and motor vibration resulting in accelerated aging of motor components. If eccentricity remains undetected, it can increase in severity, and increase the risk of stator-rotor contact, which causes forced outage of the motor and driven process. Detection of eccentricity currently relies on off-line testing and on-line vibration/current spectrum analysis, which are inconvenient or cannot provide reliable detection as they are influenced by other mechanical non-idealities in the motor or load. In this paper, the feasibility of using the signals from analog Hall-effect field sensors for detecting eccentricity is investigated. It is shown that Hall sensors already present in machines for motion control can be used for measuring the variation in the flux inside the motor due to eccentricity. 3-dimensional (3D) finite element analysis (FEA) and experimental results performed on an interior PMSM (IPMSM) show that the proposed method can provide sensitive and reliable detection of dynamic and mixed eccentricity with minimal hardware modifications.

[1]  T.G. Habetler,et al.  Nonstationary Motor Fault Detection Using Recent Quadratic Time–Frequency Representations , 2006, IEEE Transactions on Industry Applications.

[2]  Luc Dupre,et al.  An Experimental Design for Static Eccentricity Detection in Synchronous Machines Using a Cramér–Rao Lower Bound Technique , 2015, IEEE Transactions on Energy Conversion.

[3]  Miguel Delgado Prieto,et al.  Feature Extraction of Demagnetization Faults in Permanent-Magnet Synchronous Motors Based on Box-Counting Fractal Dimension , 2011, IEEE Transactions on Industrial Electronics.

[4]  Alex Simpkins,et al.  Position estimation and control of compact BLDC motors based on analog linear Hall effect sensors , 2010, Proceedings of the 2010 American Control Conference.

[5]  Babak Nadjar Araabi,et al.  Pattern identification for eccentricity fault diagnosis in permanent magnet synchronous motors using stator current monitoring , 2010 .

[6]  S. Ahmed,et al.  Detection of Rotor Slot and Other Eccentricity-Related Harmonics in a Three-Phase Induction Motor with Different Rotor Cages , 2001, IEEE Power Engineering Review.

[7]  T.G. Habetler,et al.  Dynamic Eccentricity and Demagnetized Rotor Magnet Detection in Trapezoidal Flux (Brushless DC) Motors Operating Under Different Load Conditions , 2007, IEEE Transactions on Power Electronics.

[8]  Dong Myung Lee,et al.  Permanent magnet temperature estimation in PM synchronous motors using low cost hall effect sensors , 2016, 2016 IEEE Energy Conversion Congress and Exposition (ECCE).

[9]  K. H. Lee,et al.  Comprehensive Analysis of Magnet Defect Fault Monitoring Through Leakage Flux , 2017, IEEE Transactions on Magnetics.

[10]  Ruh-Hua Wu,et al.  Applications of linear Hall-effect sensors on angular measurement , 2011, 2011 IEEE International Conference on Control Applications (CCA).

[11]  J. Rosero,et al.  Fault detection of eccentricity and bearing damage in a PMSM by means of wavelet transforms decomposition of the stator current , 2008, 2008 Twenty-Third Annual IEEE Applied Power Electronics Conference and Exposition.

[12]  Jawad Faiz,et al.  Magnetic field and vibration monitoring in permanent magnet synchronous motors under eccentricity fault , 2012 .

[13]  W. T. Thomson,et al.  Vibration and current monitoring for detecting airgap eccentricity in large induction motors , 1986 .

[14]  Liu Xiao,et al.  Study of the Linear Hall-Effect Sensors Mounting Position for PMLSM , 2007, 2007 2nd IEEE Conference on Industrial Electronics and Applications.

[15]  Bilal Akin,et al.  Discernment of Broken Magnet and Static Eccentricity Faults in Permanent Magnet Synchronous Motors , 2016, IEEE Transactions on Energy Conversion.

[16]  Jiancheng Fang,et al.  High-Precision Rotor Position Detection for High-Speed Surface PMSM Drive Based on Linear Hall-Effect Sensors , 2016, IEEE Transactions on Power Electronics.

[17]  T.G. Habetler,et al.  Detecting Rotor Faults in Low Power Permanent Magnet Synchronous Machines , 2007, IEEE Transactions on Power Electronics.

[18]  Anton Haumer,et al.  Detection and classification of rotor demagnetization and eccentricity faults for PM synchronous motors , 2011, 2011 IEEE Energy Conversion Congress and Exposition.