Auto Disturbance Rejection Control Strategy of Wind Turbine Permanent Magnet Direct Drive Individual Variable Pitch System Under Load Excitation

The wind turbine blades have complex stress states, and the load has the characteristics of time-varying and uncertainty. Aiming at the interference problem caused by complex and variable load characteristics to the individual pitch control system, combined with the variable-pitch load characteristics, based on the permanent magnet synchronous motor (PMSM) vector control strategy and LADRC (Auto Disturbance Rejection Speed Controller), an individual pitch speed controller is designed. Linear expansion state observer is built. The control algorithm is deduced and the relationship between each control parameter is analyzed to improve the anti-interference ability of the system to the abrupt load of the pitch. On this basis, the system position tracking controller is built. Finally, a vector control simulation model was built based on MATLB/Simulink, and a speed control simulation was carried out. The simulation results show that LADRC has a strong anti-load disturbance capability, and has better anti-disturbance resistance than PID speed control, and the position controller based on this has a better position tracking effect. At the same time, the effectiveness of the designed independent pitch speed controller has also been verified through experiments. It is of great significance for improving the conversion efficiency of wind energy.