Condition monitoring of induction motor stator windings using electrically excited vibrations

A study designed to investigate the effects of stator winding deterioration on the frequency spectra of mechanical vibration in induction machines is presented. Theoretical motivation for this condition monitoring approach is provided and experimental observations of bearing vibration are presented to provide verification. Results of the study show that specific vibration frequencies may be monitored in order to provide an assessment of stator winding integrity. This information may be used by maintenance personnel as an aid in distinguishing between electrical and mechanical problems or as supporting data for identifying electrical winding breakdown before it progresses to a catastrophic failure. Advantages of this approach are that it has the potential to provide information related to the air-gap flux created by winding deterioration that may not be readily available from voltage and current monitoring and that it is an easily-implemented procedure that may be used to supplement other monitoring techniques.