A method of controlling a wind turbine having a nacelle, a rotor, a rotating hub, a first rotor blade and at least a second rotor blade, both rotor blades being mounted to the hub. The method includes measuring the strain in the first rotor blade by a strain measurement device attached to the first rotor blade; and choosing the operational parameters of the wind turbine based on the measured strain such that fatigue damage of the second rotor blade is reduced. A wind turbine is controlled by such a method.

A method for controlling a wind energy farm is disclosed. A wake state of the wind energy farm is determined, including determining wake chains defining wake relationships among the wind turbines of the wind farm under the current wind conditions. For at least one of the wind turbines of the wind energy farm, a lifetime usage is estimated, based on an accumulated load measure for the wind turbine. In the case that the estimated lifetime usage is below a predefined lifetime usage limit, the wind turbine is operated in an overrated state, while monitoring wake effects at each of the wind turbines. In the case that a downstream wind turbine detects wake effects above a predefined wake threshold level, at least one wind turbine having an upstream wake relationship with the downstream wind turbine is requested to decrease the generated wake, e.g. by decreasing power production.

A control system is disclosed. The control system includes a wind turbine, at least one sensor configured to detect at least one property of the wind turbine to generate measurement data, and a controller communicatively coupled to the wind turbine and the at least one sensor. The controller includes at least one processor in communication with at least one memory device. The at least one processor is configured to control, during a training phase, the wind turbine according to at least one test parameter, receive, from the at least one sensor, during the training phase, first measurement data, generate, based on the at least one test parameter and the received first measurement data, a control model, receive, during an operating phase, second measurement data from the at least one sensor, and update the control model continuously based on the second measurement data.

The invention relates to a method for detecting and controlling whirling oscillations of the blades of a wind turbine. The detection of the whirling oscillations is based on measurement signal indicative of blade oscillations, and a rotation-transformation of the measurement signal from a measurement frame into at least one target frame based on the whirling oscillation frequency. The rotation-transformation comprises a backward or forward rotation transformation direction relative to a rotor rotation direction. The control is based on an oscillation component obtained from the rotation-transformed measurement signal where the oscillation component is indicative of the whirling oscillation in the backward and/or forward rotation direction.

The present invention relates to a control method and a wind turbine configured to determine a load signal of at least one component of the wind turbine, and to calculate a damage rate based on this load signal. The control method calculates and monitors the damage rate in real-time, wherein the damage rate is normalised by using a first function defining a first transition phase. A second function is afterwards applied to the normalised damage rate which defines a second transition phase. These transition phases allows for a smooth transition between different operating modes of the wind turbine. The control method may further change the power output of the wind turbine relative to the nominal power output when the output signal of the second function is determined to be stable over at least one time period.

A method, device and system for determining angle-to-wind deviation and correcting angle-to-wind; the method for determining angle-to-wind deviation comprises: obtaining historical operation data of a wind turbine group during a specific time period (S101); determining an angle-to-wind deviation value for each wind speed segment on the basis of the acquired historical operation data (S102); for any wind speed segment, determining the angle-to-wind deviation value on the basis of the actual angle-to-wind measurement value and the output power value of an environmental wind speed value at a time point within the specific time period.

A method and a device for use in variable-pitch control of a wind turbine, in said method: if a current wind speed is continuously maintained at a small wind speed, then periodically detecting whether a maintained duration of a current pitch angle of a wind turbine reaches a preset duration; once the preset duration is reached, switching a current minimum pitch angle to another minimum pitch angle.

A method for monitoring and controlling a wind turbine to minimize rotor blade damage includes receiving sensor data from one or more sensors indicative of at least one blade parameter of the rotor blade over a predetermined time period. The method also includes trending the sensor data for the predetermined time period with respect to at least one wind parameter. Further, the method includes determining at least one characteristic of the trended sensor data. Moreover, the method includes comparing the at least one characteristic of the trended sensor data to an operating threshold. In addition, the method includes implementing a control action if the comparison of the at least one characteristic of the trended sensor data and the operating threshold indicates blade damage is occurring or is likely to occur.

There is presented a wind turbine system, wherein the wind turbine system is comprising a support structure, a plurality of wind turbine modules mounted to the support structure wherein each of the plurality of wind turbine modules comprises a rotor, and wherein the wind turbine system further comprises a control system, wherein the control is arranged to execute a wind turbine system transition from a first system operational state of the wind turbine system to a second system operational state of the wind turbine system, and wherein the wind turbine system transition is performed by executing a plurality of wind turbine module transitions from a first module operational state of a wind turbine module to a second module operational state of the wind turbine module wherein the plurality of wind turbine module transitions are distributed in time with respect to each other.

A method for preventing catastrophic damage in a drivetrain of a wind turbine includes receiving, via a controller, a speed measurement of the generator of the drivetrain. The method also includes determining an electrical torque of a generator of the drivetrain of the wind turbine. The method further includes estimating, via the controller, a mechanical torque of the rotor as a function of at least one of the electrical torque and the speed measurement of the generator. Further, the method includes comparing, via the controller, the estimated mechanical torque to an implausible torque threshold, wherein torque values above the implausible torque threshold speed values greater that the implausible speed threshold. Moreover, the method includes implementing, via the controller, a control action for the wind turbine when the estimated mechanical torque exceeds the implausible torque threshold.