On-line tuning variable structure adaptive control for wind induction generator system

An induction generator (IG) speed drive with the application of a sliding mode controller and a proposed recursive least square (RLS) estimator is introduced in this paper. The rotor inertia constant, friction constant, and the disturbed mechanical torque of the IG are estimated by the proposed RLS estimator, which is composed of the RLS algorithm and a torque observer. The integral proportional (IP) speed controller can be on-line designed according to the estimated rotor parameters. Then the observed disturbance torque is fed forward to increase the robustness of the IG speed drive system. A hybrid controller is designed to drive the turbine speed to extract maximum power from the wind and adjust to the power regulation.