Detection of a short-circuit fault in the stator winding of induction motors through neighboring magnetic field harmonics

This paper studies the influence on the magnetic field outside induction motors of a short-circuit fault in the stator winding through experimental investigations and time domain finite element analysis of the electromagnetic field. The detection of the stator short-circuit fault is the result of the comparison of amplitudes of particular harmonics of the output voltage of coil sensors placed around the motor, for the healthy and faulty motor states, for no-load and loaded motor operation. A detection system with two identical coil sensors ensures increased efficiency of fault detection and offers the possibility to identify the position of the faulty coil inside the motor.