The Use of the Instantaneous-Reactive-Power Signature Analysis for Rotor-Cage-Fault Diagnostics in Three-Phase Induction Motors

In this paper, a new detection technique based on the instantaneous-reactive-power signature analysis is proposed for the diagnosis of rotor-cage faults (RCFs) in operating three-phase induction motors (IMs). This technique has been tested through the simulation of two different IMs using a mathematical model based on the winding-function approach. In order to demonstrate the capability of the proposed tool for rotor-condition monitoring, these simulations are complemented by the experimental results obtained from two IMs with several faulty rotors, powered from sinusoidal and nonsinusoidal supply voltages. The results obtained by the fast-Fourier-transform algorithm and the Welch method show the merits of the proposed approach for the detection of RCFs. A suitable fault-severity factor is also proposed as an indicator of the motor condition. Moreover, the inductive reactive effect of RCFs is underlined to demonstrate the effectiveness and convenience of this new technique for the diagnosis of RCFs in three-phase IMs.