DefinePK

Abstract

Since the wind speed is random and unpredictable, the control of the power flowing between the wind energy conversion system (WECS) and the electric grid is challenging. In this paper, the active disturbance rejection controller (ADRC) and the PI controller are used in the control of a variable speed wind system based on the doubly fed induction generator (DFIG). This generator is controlled via its rotor which is connected to the grid by two back to back converters, a DC bus and a filter. For the rotor side converter (RSC), the voltage reference is provided by the rotor current control loop. This control loop gets its reference from the maximum power point tracking (MPPT) algorithm used to maximize the power extracted from the wind. As for the grid side converter (GSC), its voltage reference is obtained from the DC voltage regulation. All is simulated in Matlab/Simulink environment and both controllers are compared in terms of reference tracking and robustness against parametric variations. Results show that ADRC drives the system to its reference quicker than the PI with no weakness to modeling errors or parametric variations and with respect to the desired time response. In addition, the test results proved a high sensitivity of the PI controller to parametric variations.