Detection of lamination faults from rotating, magnetic fields

Detection of lamination faults is key in the prevention of more serious generator core damage. Localized stator core faults occur frequently in rotational flux zones. Therefore, this paper studies the behavior of rotational flux in the presence of shorted laminations. Faults result in a redistribution of the magnetic field across the sample and hence the flux density distribution. Different sizes and positions of faults are simulated. Moreover a fault is imposed between two laminations and the associated rotational core losses measured. Experimental results show a distortion in the measured magnetic field with a 5% difference between the normal and faulted rotational core losses samples.