Optimal Power Regulating for Wind Turbine with LQR and Disturbance Accommodation Pitch Control

Abstract

For variable speed variable pitch wind turbine with constant torque control, PI variable pitch control is often used as traditional control strategies. The drive-train damping is too small, which is easy to cause resonance under wind disturbance. Based on the optimal control theory, this paper establishes a control-oriented model considering the dynamic of the drive-train, generator and pitch actuator. Controller is designed by using Disturbance Accommodation Control (DAC) augmented model which is an enhanced version of Linear Quadratic Regulator (LQR). Then, state is obtained and the disturbance is reconstructed by selecting suitable gain matrix of observer. In order to verify the effectiveness of the proposed method, the LQR and PID controller are implemented on MATLAB/Simulink. The results show that LQR method has better adjustment effect on output power.