Control and Investigation of Operational Characteristics of Variable Speed Wind Turbines with Doubly Fed Induction Generators

This article deals with the analysis, modeling, and control of the doubly-fed induction generator (DFIG) for wind turbines. The DFIG wind turbine can deliver more energy to the grid. There are some different methods to modify the DFIG system in order to accomplish the stator reactive power proposed. One of these methods is to modify the DFIG system for nominal voltage to evaluate cost and materials-efficiency consequences. A specific control strategy is implemented according to the vector control strategy. The proportional-integral (PI) regulators used are simple and precise controllers. This type of regulation, which is closed-loop rotor currents, allows adjustment of the sliding of the DFIG. This gives a good adjustment of the powers of the stator and the rotor. The percentage error of the simulation is less than 2 %. The results obtained in these investigations show that it is possible to adjust the powers of the stator, even with a variation of the parameters. The developed method will allow achieving the maximum efficiency of the wind energy conversion chain. The objective of this article is to optimize the quality of energy generated by wind turbines by controlling the reactive stator power and reducing the losses of the energy of the reactive stator power, which must be a physically minimal value. The results will be presented in the Matlab - Simulink environment.