Design Of Brushless Doubly-Fed Generator And Research On Control Of Grid-Connected Bariable Speed Wind Power Generation

Globally enthusiastic research has been focused on the exploitation of wind power as a source of renewable energy. Benefited from the ceaseless development of information technology and control technique, research on grid-connected wind power generation has been in fast progress, with commercial application from several kilowatts up to more than one megawatts per unit, and category of controls from stall type to pitch regulation type up to the state-of-the-art varying speed type.The thesis is about the work around the centerpiece of varying speed constant frequency wind power generation unit.In the first stage, due to the research in years on the magnetic field modulation type doubly fed brushless machine, two doubly fed generators was requested to fabricate. The work has been done, including manufacturing and testing, as one main part of this paper. A setback at the double fed running test has been understood not as a problem but a signaling for the indispensable study on the control strategy and system of doubly fed operation.Following this conclusion, various kind of AC speed control rules have been analyzed with the favor given to the self-controlled frequency regulation drive. Machine model for doubly fed power generation has been given and control equations are discussed. Consequently, the vector control strategy for doubly fed generation has been presented.Last but not least, based on the aerodynamics of wind power machines, using the torque observer and speed estimator, a linearized direct speed control wind power generation model has been presentated.