Patent ID: 8096761

Claim:
A method for operating a wind turbine during degraded blade aerodynamic conditions comprising: providing a wind turbine having at least one blade having adjustable pitch angle that is adjusted according to an operational parameter schedule, the operational parameter schedule including a control algorithm or a coefficient of power curve; regulating the wind turbine through a control scheme in response to a degraded blade aerodynamic condition, the control scheme comprising: determining a wind speed and rotor speed; calculating a blade efficiency parameter in response to the wind speed and the rotor speed; determining a minimum pitch angle in response to the blade efficiency parameter, wherein the minimum pitch angle is determined by relating the blade efficiency parameter to a blade pitch at a predetermined value of the operational parameter; maintaining the pitch angle of the at least one blade in response to the blade efficiency parameter at an angle equal to or greater than the determined minimum pitch angle, wherein maintaining the pitch angle of the at least one blade is independent of the operational parameter schedule, wherein maintaining the pitch angle is configured to reduce or substantially eliminate aerodynamic stall during the degraded blade aerodynamic condition; and departing from the control scheme when the degraded blade aerodynamic condition is no longer detected.