Contribution à la commande des machines électriques

Abstract

The objective of this thesis is to optimize the design of a wind energy conversion system by establishing an optimal balance between cost, energy efficiency, system performance, and the quality of energy injected into the electrical grid. To achieve this objective, we conducted modeling, control, and simulation of a wind generator consisting of a wind turbine, a brushless doubly fed reluctance machine BDFRM, back-to-back converters, and a control block.The control block is divided into two parts: generator-side converter control and gridside converter control. Modeling of various control-related elements, such as the DC bus and the GSC-grid link filter, was performed. The primary stator of the machine, operating as a generator, is directly connected to the electrical grid, while the secondary stator is connected via back-to-back converters, enabling control of the entire wind system. Techniques such as stator flux orientation, first and second-order sliding mode control, and Maximum Power Point Tracking (MPPT) control were applied to the control block to independently control the active and reactive powers sent to the electrical grid by the generator and extract maximum power.Simulation results of the overall wind system demonstrate the effectiveness of the MPPT control. They confirm that independent control of the active and reactive powers sent to the electrical grid by the wind generator has been successfully achieved using stator flux orientation. The nonlinear control methods examined in this study have demonstrated high performance in managing the wind energy conversion system. Simulation results have confirmed the efficiency and robustness of each method in terms of tracking, unity power factor operation, decoupling, response time, and current quality.