Integrated pitch control for wind turbine based on a novel pitch control system

A novel pitch control system is proposed for wind turbine to smooth output power and load fluctuations. This system is driven by a servo-valve controlled hydraulic motor and is precisely controlled to track the desired pitch angle trajectory. Nonlinear modeling and characteristics of this system are presented and analyzed. An adaptive nonlinear sliding mode pitch angle controller is designed to deal with the uncertainties and external disturbances in this system. An integrated pitch control strategy is proposed to generate the reference pitch commands for this system by considering the load reductions. The proposed system, pitch controller, and the control strategy have been validated for efficient and accurate pitch control performances by comparative experimental results under realistic wind speeds.