Magnetic field and vibration monitoring in permanent magnet synchronous motors under eccentricity fault

In this study, a novel frequency pattern is extracted from magnetic field analysis for precise eccentricity fault recognition in permanent magnet synchronous motors (PMSMs). In this analysis, impacts of stator slots, saturation, static and dynamic eccentricities are taken into account. Radial force and unbalanced magnetic pull are evaluated analytically and their spectra are utilised for vibration monitoring in the faulty PMSM. Furthermore, a frequency pattern is presented based on the processing of the radial force in PMSM under eccentricity fault. Since in the finite-element method, geometrical characteristics of all parts of the motor, spatial harmonics because of the stator slots, saturation owing to non-linear characteristics of the ferromagnetic materials in the stator and rotor cores and spatial distribution of stator windings are considered, two-dimensional (2D) and three-dimensional (3D) time-stepping finite-element method (TSFEM) are employed for modelling and analysing PMSM under static and dynamic eccentricities. The results obtained from the analytical approach introduced are validated by 2D and 3D TSFEM solutions. Simulation results are verified by experimental results.

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