Prospects of a collective pitch control by means of predictive disturbance compensation assisted by wind speed measurements

Abstract

A simple but robust and effective method to improve collective pitch control of variable-speed wind turbines given information on future inflow is proposed. The present paper focuses on the design and prospects of a control concept using predictive disturbance compensation. This feed-forward control structure is based on calculation of a future effective wind speed, on static disturbance compensation from steady turbine data and on estimation of the dynamic behavior. The control strategy is evaluated with regards to stability, robustness and performance in frequency and time domain. The required wind field information is currently not available for common control, but can in general be obtained from measurements with remote sensing technologies and wind modeling. Significant reductions of rotor speed variations, mechanical loads and pitch activity at fatigue and extreme operating conditions are demonstrated.