ShamsMosavi S., Poshat J., Zarei J.

One of the main induction motor defects is the broken rotor bar. Detection of this defect using Motor Current Signature Analysis (MCSA) requires proper motor loading. However, almost this is a difficult or impossible task. In this paper, we suggest the usage of a decreased supply voltage instead of motor loading. By decreasing the motor's supply voltage, inertia and friction of the shaft, in comparison with the low supplying power and voltage of motor, acts as a uniform load, and hence excites broken bar frequencies. On the other hand, by increasing rotor's slip, and thus the separation of defect harmonics from the main supplying frequency, detection of these defect frequencies become easier.