A frequency-domain detection of stator winding faults in induction machines using an external flux sensor

The aim of this paper is to present the advantage of stator fault detection using an external flux sensor in working induction machine. In the past twenty years, axial flux sensors have been used for diagnosis purpose but rarely in presence of complex power supply such as voltage static inverter. In this paper, it is proved that a simple external flux sensor is more efficient than the classical stator current analysis to detect intern-turn short circuit in three-phase induction machine. The new result is that, even in presence of power supply harmonics, it is possible to detect easily the stator winding faults in the low frequency range of the flux spectrum with low frequency resolution.