System and method for protecting wind turbines from extreme and fatigue loads

1. A method for protecting a wind turbine from extreme and fatigue loads associated with high wind speed events, the method comprising:

receiving an indication from wind speed sensors that wind speed measurements exceed a predetermined storm threshold and cannot be used due to the high wind speed events;

in response to receiving the indication, receiving, via a wind turbine condition estimator programmed in a turbine controller of the wind turbine, operating data indicative of current wind turbine operation, the operating data comprising pitch angle, rotor speed, power output, generator torque, yaw angle, one or more environmental conditions, and data from one or more loading sensors of the wind turbine;

estimating, via the wind turbine condition estimator, a plurality of estimated wind turbine conditions at the wind turbine by solving a control algorithm having one or more equations using the operating data, the plurality of estimated wind turbine conditions comprising, at least, an estimated wind speed at the wind turbine and at least one loading proxy of the wind turbine; and,

implementing, via the turbine controller, a corrective action only when each of the estimated wind speed at the wind turbine and the at least one loading proxy of the wind turbine indicates that one or more loading conditions of the wind turbine exceeds a predetermined limit.

2. The method of claim 1 , wherein the predetermined storm threshold comprises wind speeds greater than about 20 meters/second.

3. The method of claim 1 , wherein the loading proxy comprises at least one of a loading of one or more wind turbine components, air density, wind turbulence, and/or wake from neighboring turbines.

4. The method of claim 1 , wherein determining, via the wind turbine condition estimator programmed in the turbine controller of the wind turbine, the plurality of estimated wind turbine conditions at the wind turbine using the control algorithm having the one or more equations further comprises:

solving, via the wind turbine condition estimator, the one or more equations using the operating data and one or more aerodynamic performance maps, the one or more aerodynamic performance maps being dimensional or non-dimensional tables that describe rotor loading and performance under given conditions, the given conditions comprising density, wind speed, rotor speed, and pitch angle; and,

determining the plurality of estimated wind turbine conditions based on the solved equations.

5. The method of claim 1 , wherein the operating data comprises at least one of pitch angle, generator speed, rotor speed, power output, generator torque, yaw angle, one or more environmental conditions, data from one or more loading sensors of the wind turbine, or functions thereof.

6. The method of claim 5 , wherein the one or more environmental conditions comprises at least one of wind speed, air density, ambient temperature, pressure, humidity, presence of precipitation, wind direction, wind gust, wind shear, wind acceleration, wind turbulence, wind veer, wake, or wind deviation.

7. The method of claim 1 , further comprising determining, via the wind turbine condition estimator, the plurality of estimated wind turbine conditions at the wind turbine online and in real-time.

8. The method of claim 1 , wherein implementing the corrective action when each of the plurality of estimated wind turbine conditions indicate that the one or more loading conditions of the wind turbine exceeds the predetermined limit further comprises at least one of shutting down the wind turbine or derating the wind turbine.

9. The method of claim 8 , further comprising:

determining, via the wind turbine condition estimator, an estimated wind speed offline after implementing the corrective action; and,

restarting the wind turbine or uprating the wind turbine only after the estimated wind speed is below the predetermined limit.