Contribution à la conception de la machine à réluctance variable en vue de sa commande

Abstract

The principal goal of this thesis is to simulate the Switched reluctance machine (SRM) by FEMM software in order to obtain the electromagnetic characteristics of the SRM. The approach of modelling used in this case is a finite element approach. The second goal relates to the alimentation improvement of the SRM in order to minimize the torque ripples. That is carried out by the suitable choice of the overlap angle. For the first objective, we made several simulation tests by the change of the rotor position and with various values of the alimentation current. The results of the electromagnetic characteristics (torque, flux and inductance) obtained are acceptable. These results can give notable improvements to the second objective. The electromagnetic characteristics obtained are exploited in order to control the SRM (by using SIMULINK/MATLAB) and for obtaining the optimal overlap angle minimizing the torque ripples. We used two control strategies: voltage control for high speeds and a hysteresis control for the low and medium speeds. We also adopted two simulation models, the first is a linear model and the second is a nonlinear model. According to my results, the nonlinear model is the best adapted to describe the machine operation.