Analysis of Air Gap Flux to Detect Induction Motor Faults

This paper presents the application of motor flux signature analysis to the detection of stator winding failures, broken rotor bars and end ring faults in induction motors. Air gap flux analysis is a non-invasive, on line monitoring technique to diagnose faults in three-phase induction motor drives, detecting differences in the flux spectrum. In this work a programme developed in LabVIEW to perform data acquisition and analysis is presented. Data is read in real time form the working induction motor, and the program provides three fault indicators were found: rotor bar failure, rotor end ring failure and stator winding turn to turn short circuit. With these three indicators failure location, state and cause can be determined. The system has being validated in the laboratory with motors with known faults, and a portable version for industrial workshop tests is being developed