Permanent magnet vernier generator under dynamic eccentricity fault: diagnosis and detection

Permanent magnet vernier generators (PMVGs) are suitable for meeting power concussion requirements of traffic enforcement cameras and traffic-driven applications. In this study, the performance of PMVGs at no-load and full-load are analysed in healthy machines and machines under different types of mechanical faults including static eccentricity, dynamic eccentricity, inclined rotor, and run-out faults. Furthermore, an analytical model is developed to estimate the air-gap permeance and the induced voltages in the healthy generator and generator under the above-mentioned mechanical faults. Then, the performance of the generator is predicted using a two-dimensional and three-dimensional time stepping finite-element method. Finally, from the stator current spectrum of the PMVG under dynamic eccentricity fault, the amplitude of the side-band components with a specific frequency pattern is extracted and compared with experimental results.