Adaptive LQR control with Kalman filter for the variable-speed wind turbine in Region II

Abstract

An ALQR (Adaptive Linear Quadratic Regulation) method for the variable speed wind turbines system is proposed in this paper. The controller is designed for the wind turbine operating in the low wind speed (Region 2), in which the pitch of the blades is fixed at the optimal angle. Since the wind turbine is a nonlinear system, the Kalman filter and the adaptive method are implemented in the controller to make the LQR compatible with the nonlinear system. The proposed control scheme is compared in the simulation with several commonly used control methods, i.e. look-up table, PID control and gain-scheduling method. The step changed wind speed profile and the turbulent wind speed profile are adopted for the tests. The results of the simulations show that the proposed ALQR method is much better than the conventional methods.