Abstract: A method for damping vibration in a wind turbine including aerodynamic devices for influencing the airflow flowing from the leading edge of a rotor blade of the wind turbine to the trailing edge of the rotor blade, each aerodynamic device being movable by an actuator between a first protruded configuration and a second retracted configuration is provided. The method includes measuring vibrations in the wind turbine, if the measured vibrations are greater than a threshold within a predefined frequency band, moving a portion of the aerodynamic devices to the second retracted configuration and continuing to measure vibrations, if the measured vibrations are still greater than a threshold within a frequency band, reducing the pitch angle interval of the blade and continuing to measure vibrations, if the measured vibrations are still greater than a threshold within a frequency band, moving all the aerodynamic devices to the second retracted configuration.

Abstract: A control system for positioning at least two floating wind turbines in a wind farm is provided. The control system includes a measuring device configured for measuring an incoming wind field at the two wind turbines, a determining device, wherein the determining device is configured for determining a wake property at the two wind turbines, wherein the determining device is configured for determining a propagation path of the wake property through the wind farm based on the determined wake property at the at least two floating wind turbines, wherein the determining device is configured for determining a location for each of the at least two floating wind turbines including a minimized wake influence based on the determined propagation path of the wake property through the wind farm, and a repositioning device configured for repositioning each of the at least two floating wind turbines to the determined location.

Abstract: A wind turbine including: at least a rotor blade including an aerodynamic device for influencing the airflow flowing from the leading edge section of the rotor blade to the trailing edge section of the rotor blade, wherein the aerodynamic device is mounted at a surface of the rotor blade, an actuator of the aerodynamic device for actuating the aerodynamic device at least between a first protruded configuration and a second retracted configuration, a pressure supply system for operating the actuator by means of a pressurized fluid, an acoustic receiver for measuring an acoustic signal in the pressure supply system, and a diagnostic unit connected to the acoustic receiver and configured for deriving an operative status of the aerodynamic device based on the acoustic signal, is provided.

Abstract: Provided is a system for determining an amount of oscillating movement of a wind turbine, the wind turbine including a tower, a non-rotating upper part supported by the tower, a rotor having a rotor axis, and a generator for generating electric power. The system includes (a) a sensor unit adapted to provide a rotor speed signal indicative of a rotational speed of the rotor relative to the non-rotating upper part, (b) a filtering unit adapted to, based on the rotor speed signal provided by the sensor unit, provide a filtered signal including information associated with an oscillating movement of the wind turbine, and (c) a processing unit adapted to determine the amount of oscillating movement based on the filtered signal provided by the filtering unit. Furthermore, a wind turbine and a method are described.

Abstract: Provided is a method of setting and clearing a full-power flag in a control process running on a wind turbine controller, the method including (a) acquiring a set of measured values and/or reference values for: rotor speed, output power, blade pitch angle, and activation level of an adaptive flow regulating system, (b) determining that a first condition is fulfilled when the value of the rotor speed equals a speed limit value and the output power reference value equals a power limit value, (c) determining when the blade pitch angle reference value fulfills a pitch condition and the activation level of the adaptive flow regulating system fulfills an adaptive flow regulating condition, or when the measured value of the rotor speed is below the speed limit value, (d) setting the full-power flag, and (e) clearing the full-power flag. Furthermore, a wind turbine controller and a wind turbine including such a controller.

Abstract: Provided is a wind turbine and to a method and a device for controlling aerodynamic properties of a blade of the wind turbine, the blade including a predetermined number of add-on members which are actuated by a corresponding trim actuator to alter the aerodynamic properties of the blade, wherein each trim actuator is configured to hold the add-on member in a predetermined first position and a predetermined second position. The control device is configured to determine a first number of add-on members which are to be held at the predetermined first position, and to determine a second number of add-on members which are to be held at the predetermined second position.

Abstract: Provided is a wind turbine including: at least a rotor blade including an aerodynamic device for influencing the airflow flowing from the leading edge section of the rotor blade to the trailing edge section of the rotor blade, wherein the aerodynamic device is mounted at a surface of the rotor blade, a pressure supply system for providing a pressurized fluid for operating the aerodynamic device between a first protruded configuration and a second retracted configuration, a control unit for controlling the pressure supply system, a monitor unit for monitoring a pressure and/or a flow rate of the pressurized fluid, and configured for: receiving a measured pressure and/or flow rate signal in at least one section of the pressure supply system, deriving an operative status of the aerodynamic device based on the measured pressure and/or flow rate signal.

Abstract: A method for damping vibration in a wind turbine including aerodynamic devices for influencing the airflow flowing from the leading edge of a rotor blade of the wind turbine to the trailing edge of the rotor blade, each aerodynamic device being movable by an actuator between a first protruded configuration and a second retracted configuration is provided. The method includes measuring vibrations in the wind turbine, if the measured vibrations are greater than a threshold within a predefined frequency band, moving a portion of the aerodynamic devices to the second retracted configuration and continuing to measure vibrations, if the measured vibrations are still greater than a threshold within a frequency band, reducing the pitch angle interval of the blade and continuing to measure vibrations, if the measured vibrations are still greater than a threshold within a frequency band, moving all the aerodynamic devices to the second retracted configuration.

Abstract: Provided is a method of correcting a measurement value of least one wind characteristic, in particular wind speed and/or wind direction, related to a wind turbine having a rotor with plural rotor blades at least one having an adaptable flow regulating device installed, the method including: measuring a value of the wind characteristic; obtaining state information of the adaptable flow regulating device; and determining a corrected value of the wind characteristic based on the measured value of the wind characteristic and the state information of the adaptable flow regulating device.

Abstract: Provided is a device and a method of damping front and backward movements of a tower of a wind turbine, wherein the wind turbine includes the tower and a rotor, the rotor being mounted at the top of the tower to rotate about a rotational axis in which the front and backward movements of the tower occur, and the rotor has a plurality of blades, wherein each blade has at least one corresponding active add-on member which is actuated by a corresponding actuator to alter aerodynamic properties of the blade. Each add-on member is actuated by the corresponding actuator to alter the aerodynamic properties of the blade in a manner that the rotor is configured to damp the front and backward movements of the tower of the wind turbine.

Abstract: Provided is a blade for a wind turbine, the blade including a joint section configured to connect the blade to a hub of the wind turbine; an active add-on member which is actuated by a corresponding trim actuator to alter aerodynamic properties of the blade; and a channel configured to supply a medium from the joint section to the active add-on member. A wind turbine and a method of preventing icing of the blade is also provided.

Abstract: A wind turbine including: at least a rotor blade including an aerodynamic device for influencing the airflow flowing from the leading edge section of the rotor blade to the trailing edge section of the rotor blade, wherein the aerodynamic device is mounted at a surface of the rotor blade, an actuator of the aerodynamic device for actuating the aerodynamic device at least between a first protruded configuration and a second retracted configuration, a pressure supply system for operating the actuator by means of a pressurized fluid, an acoustic receiver for measuring an acoustic signal in the pressure supply system, and a diagnostic unit connected to the acoustic receiver and configured for deriving an operative status of the aerodynamic device based on the acoustic signal, is provided.

Abstract: A method of controlling a wind turbine including a plurality of rotor blades, a first controller for controlling an adaptive flow regulating system having a plurality of individually controllable adaptive flow regulating devices arranged on the rotor blades, and a second controller for controlling a pitch regulating system for regulating a pitch angle of each rotor blade. The method includes (a) determining a diagnostic value indicative of an operational efficiency of the adaptive flow regulating system, (b) determining a first gain value for the first controller and a second gain value for the second controller based on the diagnostic value, (c) applying the first gain value to control signals for the adaptive flow regulating system generated by the first controller, and (d) applying the second gain value to control signals for the pitch regulating system generated by the second controller, is provided.

Abstract: Provided is a method for detecting the operative status of an aerodynamic device for influencing the airflow which flows from the leading edge of a rotor blade for a wind turbine to the trailing edge of the rotor blade, the aerodynamic device being movable by an actuator between a first protruded configuration and a second retracted configuration. The method includes the steps of measuring a temporal course of an operational value of the wind turbine, comparing the measured temporal course of the operational value with a desired temporal course of an operational value, and deriving an operative status of the aerodynamic device.

Abstract: Provided is a system for determining an amount of oscillating movement of a wind turbine, the wind turbine including a tower, a non-rotating upper part supported by the tower, a rotor having a rotor axis, and a generator for generating electric power. The system includes (a) a sensor unit adapted to provide a rotor speed signal indicative of a rotational speed of the rotor relative to the non-rotating upper part, (b) a filtering unit adapted to, based on the rotor speed signal provided by the sensor unit, provide a filtered signal including information associated with an oscillating movement of the wind turbine, and (c) a processing unit adapted to determine the amount of oscillating movement based on the filtered signal provided by the filtering unit. Furthermore, a wind turbine and a method are described.

Abstract: Provided is a method of monitoring the structural integrity of a supporting structure of a wind turbine, which method includes the steps of determining a fore-aft tower oscillation frequency; determining a side-to-side tower oscillation frequency; computing a working structural indicator value from the fore-aft tower oscillation frequency and the side-to-side tower oscillation frequency; comparing the working structural indicator value to a reference working structural indicator value; and issuing an alarm if the difference between the working structural indicator value and the reference structural indicator value exceeds a predefined threshold. Also provided is a system for monitoring the structural integrity of a supporting structure of a wind turbine, a wind turbine, and a computer program product for carrying out the steps of the inventive method.

Abstract: The following arrangement for determining actual rotor speed in a wind turbine, the wind turbine including a tower, a non-rotating upper part supported by the tower, a rotor having a rotor axis, and a generator for generating electrical power is provided. The arrangement includes: (a) a first sensor unit adapted to be arranged at the non-rotating upper part of the wind turbine to detect a rotational speed of the rotor, (b) a second sensor unit adapted to detect an angular roll speed of the non-rotating upper part, and (c) a processing unit adapted to determine the actual rotor speed by subtracting the angular roll speed detected by the second sensor unit from the rotational speed detected by the first sensor unit is also provided.

Abstract: Provided is a thrust bearing for a wind turbine including a thrust collar rotatable around a longitudinal axis of the thrust bearing and having a thrust surface transversally oriented with respect to longitudinal axis, a support structure fixed with respect to the longitudinal axis of the thrust bearing, a bearing pad contacting the thrust surface of the thrust collar and movable on a pad seat provided on the support structure, a spring element interposed between the bearing pad and the support structure.

Abstract: Provided is a thrust bearing for a wind turbine including a thrust collar rotatable around a longitudinal axis of the thrust bearing and having a thrust surface transversally oriented with respect to longitudinal axis, a support structure fixed with respect to the longitudinal axis of the thrust bearing, a bearing pad contacting the thrust surface of the thrust collar and movable on a pad seat provided on the support structure, a spring element interposed between the bearing pad and the support structure.

Abstract: A method and corresponding arrangement are provided for determining pitch angle adjustment signals for adjusting a pitch angle of a rotor blade connected to a rotation shaft of a wind turbine. The method includes obtaining a first maximal speed signal indicative of a first desired maximal rotational speed of the rotation shaft. The method also includes deriving a first pitch angle adjustment signal based on the first maximal speed signal. The method further includes obtaining a second maximal speed signal indicative of a second desired maximal rotational speed of the rotation shaft different from the first desired maximal rotational speed of the rotation shaft. Further, the method includes deriving a second pitch angle adjustment signal based on the second maximal speed signal. The second pitch angle adjustment signal is different from the first pitch angle adjustment signal.