Diagnosis of simultaneous broken rotor bars and static eccentricity faults of induction motors by analyzing stator current and vibration signals

It is important to detect the faults of induction motors in an accurate manner due to their widespread use in industrial production processes. Broken rotor bars and eccentricity faults are the common faults of induction motor. The simultaneous occurrence of these two types of faults is often encountered in industrial facilities. Therefore, it is important to properly detect characteristic harmonic components of these types of faults. It is difficult to detect these components at low loading and noisy conditions. In this paper, the simultaneous broken rotor bars and static eccentricity faults are investigated based on the stator current and vibration signals. Hilbert envelope analysis was applied to the stator current and vibration signals under four different loading levels (25%, 50%, 75% and 100%) of induction motor. The frequencies and amplitudes of characteristic harmonic components have been successfully detected in envelope spectrum. The results show that the proposed method can be used to diagnose the simultaneous broken rotor bars and eccentricity faults of induction motors.