An aerodynamic torque observer for the robust control of variable-speed wind turbines

This paper focuses on a robust power generation control strategy for a variable speed wind energy conversion system based on a permanent magnet synchronous generator. The proposed control strategy combines a robust observer of the aerodynamic torque with a Sliding Mode (SM) based field oriented control strategy. The robust vanishing of the observation error and the tracking error is proved. Reported numerical simulations show that the proposed SM approach is effective in terms of optimal power extraction and it is robust with respect to uncertainties affecting the system.