Vibration monitoring for wound rotor induction machine winding fault detection

This paper investigates wound rotor induction machine winding fault detection by vibration monitoring. The influence of stator open-circuit faults on machine operation is first examined using a time-stepped circuit model. The calculations indicate that fault specific changes exist in the machine torque and therefore the vibration signal. Model predictions are validated by torque and vibration signals measurements on a commercial 30kW machine. The paper establishes closed form expressions that enable the evaluation of torque and vibration signals spectral frequencies and linking these to healthy and faulty operating conditions.