Performance improvement of a doubly-fed induction generator based WECS using intelligent techniques

Type-three wind turbines utilize doubly-fed induction generators that are equipped with rotor-side and grid-side converters. Rotor side converters are responsible for harvesting electric power from the wind. Control loops that act on the rotor side converters are the focus of this work. Since fuzzy systems represent nonlinear mappings from the input to the output spaces, they emerge as promising candidates to design efficient controllers. Two fuzzy logic controllers are proposed to replace the conventional controllers and to improve the performance. One fuzzy controller is devoted to take the control actions. The second controller will tune the scaling gains of the first to assure an enhanced performance. Simulation results based on a 9-MW wind farm connected to a utility grid are reported.