Contribution à la modélisation en compatibilité électromagnétique des machines électriques triphasées

The research presented in this report addresses the problem of electromagnetic compatibility (EMC) in AC motors, which are supplied by PWM inverters, through the predictive modeling of the common mode impedance as well as aspect related to bearing voltage. We begin with identification of the parameters that govern the propagation path of common mode currents in the metallic parts of induction machines using finite element (FE) method. From analysis of the results, a circuit model was proposed to predict these propagation paths. The next chapter deals with the relationship between the existing parasitic capacitances and the development of the bearing voltage, which is responsible for premature failure of bearings. The study is realized on a wound-rotor synchronous motor with of an electric car. These approaches bring out the predominance of the capacitive coupling between the winding and the stator. For this reason, in the third chapter we developed a program based on analytical formulations, to automatically calculate the capacitive coupling as well as electrostatic energy within the slots of low and middle power machines. We find that the obtained results are in good agreement with FE calculation and the measurement. Finally, we propose a methodology for predictive modeling of common mode impedance of the stator windings taking into consideration all the inductive and capacitive phenomena. An electric model with lumped parameters RLC is then generated, which is implantable in SPICE type software. The prediction results are in good agreement with the measurement results on frequency band [10kHz - 100 MHz].