Individual pitch control of wind turbines: Model-based approach

Journal article, 2013

Significant fore-and-aft tower vibrations of large wind turbines due to wind shear can be reduced using individual pitch control, in which the pitch angle of each blade is adjusted individually. A short survey of the existing individual pitch control strategies is presented, and a new architecture with preview measurements of the wind speeds at different heights is proposed in this article for the turbine tilt moment reduction. The approach includes look-ahead calculations of the desired blade loads and pitch angles as well as preprocessing algorithms for calculation of the derivative of the desired pitch angle. Wind speed measurement records, performed at two different heights with Risoe P2546 cup anemometer, are directly used in the turbine simulations. It is shown that the variations of tilt moment can be essentially reduced using the approach described in this article.