Bearing and misalignment fault detection in induction motors by using the space vector angular fluctuation signal

This paper describes the use of the space vector angular fluctuation (SVAF) method for bearing and misalignment fault diagnosis in induction motors. The theoretical background for SVAF is presented and it is shown how bearing and misalignment faults can be effectively diagnosed by the use of this non-invasive method. The proposed algorithm uses only stator currents as the input, without any other sensors. Both simulation and experimental results carried out on different motors show that these faults could be easily detected and differentiated from each other by fault-related frequencies, which occur in the spectrum of the SVAF.