Induction machine modelling with dynamic eccentricity fault using FMM and permeance approach

This paper deals with modelling the induction machine with dynamic eccentricity fault. The machine inductances are calculated using the magneto motive force and the air gap permeance approach taking into consideration the space harmonics effect. First, the magnitude and the form of the obtained inductances in presence of dynamic eccentricity are discussed and compared to those of the healthy machine. Next, these inductances are introduced in the general induction machine model obtained using the magnetically coupled circuits approach. Simulation results illustrate the induction machine performances for the healthy and the faulty cases. The Fast Fourier Transform (FFT) of the steady state stator current obtained by simulation is performed to detect specific components that identify the fault appearance in the machine. The detection of these components is easier when the motor is supplied from a sinusoidal voltage than when supplied from a Pulse Width Modulation (PWM) inverter.