Rotor Faults Diagnosis in Rotor Field Oriented Controlled Induction Motors Based on Torque Current

This paper proposes a new method to diagnosis rotor faults in rotor field oriented controlled (RFOC) induction motors (IMs). It is theoretically proved that the ratio between the amplitude of the oscillating component and the average of torque current in the d-q reference frame allows detection and quantification of the extension of the fault. Motor parameters are not needed except for the number of rotor bars. At the same time, the reference speed and the load level do not significantly affect the diagnosis results. The effectiveness of the scheme has been validated by simulation results.