Investigation of harmonic emissions in wound rotor induction machines

This paper investigates current harmonic emissions and the nature and the manifestation of the electromagnetically induced vibration signature in wound rotor induction machines. The strength and consistency of harmonic signatures between three industrial WRIMs with different design parameters is examined. A numerical harmonic model is used to predict and investigate WRIMs´ stator and rotor currents and electromagnetic torque signals spectra. The model results are verified by comparison with experimental measurements made on two laboratory test rigs. The presented model and experimental results demonstrate significant and highly consistent current and vibration signals spectral contents patterns between the considered industrial WRIM designs.