Stator-winding fault diagnosis of PM brushless DC motor drives

A model-based diagnostic system for stator winding inter-turn faults of PM brushless DC motor drives is presented. A transient model of the drive system is set up and run under different healthy and faulty conditions. The steady-state supply current is selected as the diagnostic signal to compare the healthy operation to the faulty operation under different loads. The supply current signal is transformed to the frequency domain using the discrete Fourier transform (DFT). Appropriate diagnostic indices are extracted from the supply current spectrum to differentiate between healthy and different faulty conditions.