On the Use of Slot Harmonics as a Potential Indicator of Rotor Bar Breakage in the Induction Machine

This paper sheds light on the additional harmonic components arising from broken bars fault in the stator line current of an induction machine, which are generalized and analyzed in a different manner than of those given in the literature. Special attention is focused on the effect of both motor slots and rotor dissymmetry on the mechanism of the generation of the different harmonic components with consideration of the unbalance voltage supply and speed ripples effects. Aside from the well-known diagnosis signatures, new ones show up. The simulation and experimental results confirm the aforementioned study.