Research on Power - load Cooperative Control of Wind Turbines Based on Variable Domain Theory

Abstract

In order to improve the operational stability of wind turbines and optimize power quality, this paper studies the blade root load and power output of wind turbines under actual working conditions from the perspective of pitch control. The calculation method of load is simplified by Coleman coordinate transformation, and the variable universe fuzzy control rule of blade load control is established. The blade root load and power output of wind turbine under three control modes of unified pitch control, d-q PID control and power load cooperative control are calculated. The results show that compared with the other two control methods, the variable universe fuzzy power-load coordinated control method has more advantages in reducing the blade root flapping torque and shimmy torque, improving the response speed, and suppressing the power output fluctuation. Especially in reducing blade root bending moment, the overshoot has decreased by 17% compared to unified pitch control.Therefore,the variable universe fuzzy PID coordinated control method is of great significance in improving the resistance to external disturbances and optimizing the output power during the operation of wind turbines.

Keywords

• wind turbine
• variableuniverse theory
• power-load coordinated control
• coleman transform
• pitch control