Detection of static eccentricity faults in AFPM machine with asymmetric windings using vibration analysis

Vibration signature has been proposed for fault diagnosis in electrical machines but its efficacy is hinged on proper determination of vibrating frequencies. Thus, this paper explores the applicability and performance of using vibration analysis on axial flux permanent magnet (AFPM) machine with asymmetric windings under static eccentricity (SE). The test rig developed to accurately replicate the faults is described and the vibration induced by electromagnetic forces associated with SE is investigated. The more dominant frequency component affected by the fault is the 2^nd harmonic of the magnetic force. The amplitude of the harmonic increased considerably with worsening SE. Along with other frequency components identified, it is proposed as an index for SE fault detection in AFPM machine.