An Approach to Discriminate between Types of Rotor and Stator Winding Faults in Wound Rotor Induction Machines

This paper presents a method to discriminate between different types of faults in the stator and rotor windings of wound rotor induction machines (WRIMs). These most common faults include inter-turn short circuit fault (ITSCF) and high resistance connection fault (HRCF). The proposed diagnostic method is based on the combination of fast Fourier transform (FFT) and discrete wavelet transform (DWT) applied on the rotor currents of WRIM. The magnetic equivalent circuit model (MEC) has been used to simulate machine performances under different winding fault conditions with Matlab/Simulink software. The experimental and simulated results for a test WRIM under various healthy and faulty conditions and different operating conditions confirm that the proposed method is feasible and sensitive to discriminate between healthy winding, ITSCF of stator winding, ITSCF of rotor winding, HRCF in the stator side, HRCF in the rotor side, and grid voltage unbalance conditions.