Adaptive H∞ Control of Large Wind Turbines

Modern, large wind turbines require multiobjective, robust controllers in order to fulfill all the control objectives. In the presented work linear matrix inequality (LMI) approach to H-infinity control and linear parameter-varying (LPV) theory are utilized to design multivariable, adaptive controller which aims at improving rotational speed control and at reducing tower structural loads. Designed H-infinity pitch controller is implemented in the operating region above rated wind speed, in a self-sufficient structure which does not require any additonal control loops. Behaviour of the H-infinity controller is compared with the baseline control system designed by classical mehtods. Simulations are performed in professional software tool GH Bladed and the subsequent analysis is carried out by calculating damage equivalent loads (DEL).