Wind turbine FF+FB independent pitch reduction load control based on LiDAR wind speed reconstruction

Aiming at the issue of maintaining high stability and efficiency in complex wind conditions for large wind turbines, a FF+FB independent pitch reduction load control strategy based on LiDAR wind measurement reconstruction is proposed. Firstly, a wind speed reconstruction method based on the VMD-LSTM model is established. By data-driven mining of the spatiotemporal characteristics between the multi-point LiDAR wind measurement data and the equivalent wind speed estimation. Considering the influence of pitch angle on the external flow field and wind speed evolution, wind speed reconstruction is achieved to provide more accurate wind speed information for pitch control while reducing the number of pitch operations. Then, a FF+FB pitch control strategy is designed to compensate for wind speed disturbances in the dynamic wind field through feedforward braking. In the feedback control, the blade root load is fed back to the controller, and adaptive independent pitch control is implemented to reduce the load. Finally, a model of a 5MW wind power system was built on the Matlab/Simulink platform for simulation analysis and verification. The results show that compared to feedforward control and feedback control, the standard deviation of output power under FF+FB control is reduced by 23.8% and 22.7%, and the standard deviation of tower base torque and blade root flap torque is reduced by more than 14%. The proposed method can ensure the stability of unit output power under turbulent wind conditions and significantly reduce blade load.