An Effective Wind Speed Estimation Based Extended Optimal Torque Control for Maximum Wind Energy Capture

Abstract

Most variable-speed wind turbines employ advanced control scheme to improve their performance. In this paper, an extended optimal torque controller is designed based on effective wind speed estimation to control the variable-speed wind turbine. To do this, multilayer perceptron based nonlinear input-output mapping is firstly used for approximating the nonlinear aerodynamics of the wind turbine. In other words, based on this nonlinear mapping, effective wind speed is estimated from the measured rotor speed, the measured pitch angle, and the observed aerodynamic torque by the disturbance observer. After that, the optimal rotor speed command for capturing maximum wind energy is derived from the estimated effective wind speed. And then the optimal torque command is calculated by combing the standard optimal torque formula and a proportional control loop that is added to effectively reduce the moment of inertia. At last, some simulation results are validated to display the availability of the improved effective wind speed estimation algorithm and control strategy. Moreover, the corresponding simulation results indicate that compared with the existing methods, the proposed method increases the accuracy of the effective wind speed estimation by 2-7% and the energy production efficiency by 0.35%.