Abstract
Short-circuit faults in windings due to the deterioration of insulation is one of the most common faults in motor drive systems. An easy and effective fault diagnosis method is urgently required to ensure a highly reliable operation. This paper proposes a new means of identifying a stator slot in which a short-circuit fault has occurred. This study first analyzed the phenomenon after the occurrence of a short-circuit fault in winding. As the result, the magnetic field in the stator of motor was found to have changed after the occurrence of the short-circuit fault and it was clear that a change of magnetic field was affected by the frequency of voltage applied to the winding. Based on this phenomenon, a new method of identifying slots in which a short-circuit fault has occurred is proposed. Next, in order to measure the magnetic flux density emanating from windings inserted each slot, a small magnetic flux density sensor is prototyped. Finally, by using this sensor, magnetic flux density of each slot directly above are measured, the effectiveness of proposed method is verified.
