Adaptive Disturbance Rejection Control Scheme for DFIG-Based Wind Turbine: Theory and Experiments

In this paper, a new control structure is presented to extract maximum power from a wind regime. In this novel approach, a discrete-time higher order sliding-mode controller is designed as an observer to construct the reference value for the extractable power based on the condition that it operates. This is possible by tracking the optimal tip speed ratio with manipulating the voltages of the rotor in the doubly fed induction generator (DFIG) configuration. The presented structure improves the performance under abrupt changes in the wind speed and can be used for any type of optimum active power tracking algorithms. The simulations show the significant improvement in performance of the nonlinear discrete-time backstepping controller utilizing this technique.