Detection of stator short-circuit in induction machines using an external leakage flux sensor

The aim of this paper is to present the advantage of stator fault detection using an external leakage flux sensor in working induction machine. In this paper, it is proved that a simple external leakage flux sensor is more efficient than a stator current sensor to detect intern-turn short circuit in three-phase induction machines. 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 leakage flux spectrum with low frequency resolution.