Electrical fault diagnosis for an induction motor using an electromechanical FE model

This paper focuses on utilizing motor vibration as an indicator for these two electromagnetic faults in electrical machines: a broken rotor bar and an inter-turn short circuit in the stator winding. These two faults deform the magnetic field in motors, which generates additional magnetic forces in the air gap. As the result, the motor structure vibrates more, compared to the normal operation. For the purpose of fault detection, as the main subject of this paper, a 3-D model was developed in COMSOL Multiphysics. Thereafter, the radial and tangential forces (the main causes of vibration in electrical machines) were introduced to the model as boundary loads on the stator teeth. Frequency response analysis was then performed to collect acceleration data from the frame surface for each operating conditions. Finally, the simulation results illustrated that vibration is a beneficial signature for fault detection in electrical machines.