Abstract: A method for installing an add-on device onto a blade of a wind turbine includes configuring a plurality of tag lines to a wrap, the tag lines having a length to extend to a ground location when the add-on device is positioned on the blade. With the rotor, positioning the blade to a first rotated position. The add-on device is located at a desired span-wise location on the blade such that the wrap forms an open-sleeve configuration draped around the leading edge of the blade and span-wise sides of the wrap extend along pressure and suction sides of the blade adjacent a trailing edge of the blade. With the tag lines, the wrap is tensioned against the blade. Attachment devices configured with the wrap are affixed to the trailing edge of the blade.

Abstract: The present disclosure relates to devices (300) for wind turbine blades (22) and methods for reducing vibrations in wind turbines (10). More particularly, the present disclosure relates to devices (300) for mitigating vortex induced vibrations and stall induced vibrations, wind turbine blades (22) comprising such devices (300), and methods for reducing wind turbine vibrations when the wind turbine (10) is parked, especially during wind turbine installation and/or maintenance. A device (300) comprises a proximal support (310) configured to be arranged around a first portion (221) of a wind turbine blade (22), a distal support (320) configured to be arranged around a second portion (222) of the wind turbine blade (22), and a barrier (330) extending between the proximal support (310) and the distal support (320). The first portion (221) of the wind turbine blade (22) is at a different longitudinal position along the blade (22) than the second portion (222).

Abstract: A system and method are provided for reducing vibrations and loads in one or more rotor blades of a wind turbine when the rotor hub is locked against rotation, The method detects that the rotor blades are vibrating above a threshold limit, and determines one or more wind parameters for wind impacting the rotor blades. An initial orientation of the blades is also determined. Based on the wind parameters and initial blade orientation, a first angle of attack for the rotor blades is determined that will reduce the vibrations in the rotor blades. The method then determines if expected loads induced at one or more wind turbine components will exceed a threshold limit at the first angle of attack for the rotor blades. The first angle of attack is modified when the expected loads exceed the threshold limit to reduce the expected loads to below the threshold limit. A controller pitches the rotor blades to achieve the first angle of attack.

Abstract: A proactive method and related wind turbine system are provided for reducing vibrations in the rotor blades when the rotor hub is locked against rotation. The method includes determining an initial blade orientation to wind direction and wind parameters for wind impacting the rotor blades. Based on the wind parameters and blade orientation, an angle of attack is determined for the rotor blades that will at least reduce vibrations expected to be induced in the blades from the current wind conditions. With a controller, the rotor blades are pitched to achieve the angle of attack using a pitch control system. The angle of attack is determined and the rotor blades are pitched from the initial blade orientation to the new angle of attack prior to vibrations being induced in the rotor blades.

Abstract: A vibration mitigating device for engagement with a wind turbine blade includes an air flow modifying element that is configurable between a retracted configuration and an extended configuration. A frame is attachable to and has a fixed length in a span-wise direction of the wind turbine blade. The air flow modifying element is movable along the frame between the retracted configuration and the extended configuration. In the retracted configuration, the modifying element extends between the blade tip and the blade root with a first spanwise length, and in the extended configuration the modifying element extends between the blade tip and the blade root with a second, greater spanwise length.

Abstract: A proactive method prevents vibrations in one or more rotor blades of a wind turbine when the wind turbine is in a standstill idling state with a rotor hub free to rotate. The method determines a minimum revolution rate of the rotor blades that prevents vibrations of the rotor blades and that the actual revolution rate of the rotor blades is below the minimum revolution rate. A wind parameter is detected and determined to be above a threshold limit. The method also detects if grid power is available for pitching the rotor blades. Based on the wind parameter, a controller determines a pitch angle for one or more of the rotor blades to increase rotation of the blades to at least the minimum revolution rate. The controller initiates pitching the rotor blades to increase the revolution rate of the rotor blades prior to vibrations being induced in the rotor blades.

Abstract: A method for installing an add-on device onto a blade of a wind turbine includes configuring a plurality of tag lines to a wrap, the tag lines having a length to extend to a ground location when the add-on device is positioned on the blade. With the rotor, positioning the blade to a first rotated position. The add-on device is located at a desired span-wise location on the blade such that the wrap forms an open-sleeve configuration draped around the leading edge of the blade and span-wise sides of the wrap extend along pressure and suction sides of the blade adjacent a trailing edge of the blade. With the tag lines, the wrap is tensioned against the blade. Attachment devices configured with the wrap are affixed to the trailing edge of the blade.

Abstract: A method is provided for installing a continuous pliant add-on device (e.g., a vibration suppression device) onto a blade of a wind turbine, wherein the blade is mounted to a rotor that is atop a tower. The method includes, with the rotor, positioning the blade to a first position. A first end of the add-on device is fixed to a first end of the blade. The blade is then rotated with a pitch control system while supplying the add-on device in a first direction along a span of the rotating blade to wrap the add-on device around the blade towards an opposite second end of the blade in a first wrap pattern.

Abstract: A system and method are provided for reducing vibrations and loads in one or more rotor blades on a rotor hub of a wind turbine when the rotor hub is in a locked or idling condition. A mass damper is attached at a fixed location on one or more of the rotor blades and is maintained on the rotor blades during the locked or idling condition of the rotor hub. The mass damper includes a movable mass component that is responsive to changes in the vibrations or oscillations induced in the rotor blades during the locked or idling condition of the rotor hub.

Abstract: The present disclosure relates to devices (300) for wind turbine blades (22) and methods (400) for reducing vibrations in wind turbines (10). More particularly, the present disclosure relates to devices (300) for mitigating vortex induced vibrations and stall induced vibrations, wind turbine blades (22) comprising such devices (300), and methods (400) for reducing wind turbine vibrations when the wind turbine (10) is parked, especially during wind turbine installation and/or maintenance. A device (300) is configured to be arranged around a wind turbine blade (22) and comprises three or more air flow modifying elements (305) comprising a concave outer surface (323) configured to face away from a wind turbine blade (22). The device further comprises a supporting structure (310) configured to support the plurality of air flow modifying elements (305). An angular distance (307) between adjacent air flow modifying elements (305) in cross-section is substantially constant.

Abstract: A proactive method prevents vibrations in one or more rotor blades of a wind turbine when the wind turbine is in a standstill idling state with a rotor hub free to rotate. The method determines a minimum revolution rate of the rotor blades that prevents vibrations of the rotor blades and that the actual revolution rate of the rotor blades is below the minimum revolution rate. A wind parameter is detected and determined to be above a threshold limit. The method also detects if grid power is available for pitching the rotor blades. Based on the wind parameter, a controller determines a pitch angle for one or more of the rotor blades to increase rotation of the blades to at least the minimum revolution rate. The controller initiates pitching the rotor blades to increase the revolution rate of the rotor blades prior to vibrations being induced in the rotor blades.

Abstract: A proactive method and related wind turbine system are provided for reducing vibrations in the rotor blades when the rotor hub is locked against rotation. The method includes determining an initial blade orientation to wind direction and wind parameters for wind impacting the rotor blades. Based on the wind parameters and blade orientation, an angle of attack is determined for the rotor blades that will at least reduce vibrations expected to be induced in the blades from the current wind conditions. With a controller, the rotor blades are pitched to achieve the angle of attack using a pitch control system. The angle of attack is determined and the rotor blades are pitched from the initial blade orientation to the new angle of attack prior to vibrations being induced in the rotor blades.

Abstract: A system and method are provided for reducing vibrations and loads in one or more rotor blades of a wind turbine when the rotor hub is locked against rotation, The method detects that the rotor blades are vibrating above a threshold limit, and determines one or more wind parameters for wind impacting the rotor blades. An initial orientation of the blades is also determined. Based on the wind parameters and initial blade orientation, a first angle of attack for the rotor blades is determined that will reduce the vibrations in the rotor blades. The method then determines if expected loads induced at one or more wind turbine components will exceed a threshold limit at the first angle of attack for the rotor blades. The first angle of attack is modified when the expected loads exceed the threshold limit to reduce the expected loads to below the threshold limit. A controller pitches the rotor blades to achieve the first angle of attack.

Abstract: The present disclosure relates to devices (300) for wind turbine blades (22) and methods for reducing vibrations in wind turbines (10). More particularly, the present disclosure relates to devices (300) for mitigating vortex induced vibrations and stall induced vibrations, wind turbine blades (22) comprising such devices (300), and methods for reducing wind turbine vibrations when the wind turbine (10) is parked, especially during wind turbine installation and/or maintenance. A device (300) comprises a proximal support (310) configured to be arranged around a first portion (221) of a wind turbine blade (22), a distal support (320) configured to be arranged around a second portion (222) of the wind turbine blade (22), and a barrier (330) extending between the proximal support (310) and the distal support (320). The first portion (221) of the wind turbine blade (22) is at a different longitudinal position along the blade (22) than the second portion (222).

Abstract: The present disclosure relates to devices (350) for reducing vibrations in wind turbines (10) and to methods (450) for using the devices (350) and mitigating wind turbine vibrations. More particularly, the present disclosure relates to devices (350) for reducing vortex induced vibrations and stall induced vibrations when the wind turbine (10) is parked, especially during wind turbine installation and/or maintenance, and to ways in which the devices (350) can be used, e.g. for installing them on wind turbine blades (22) or once they are already installed thereon. A vibration mitigating device (350) for mitigating vibrations of a parked wind turbine (10) is provided. The device (350) is configured to be arranged with a wind turbine blade (22). The device (350) comprises one or more air flow modifying elements (330). At least one of the air flow modifying elements (330) is configured to change between a retracted configuration (370) and an extended configuration (375).

Abstract: The present disclosure relates to devices (300) for wind turbine blades (22) and methods (400) for reducing vibrations in wind turbines (10). More particularly, the present disclosure relates to devices (300) for mitigating vortex induced vibrations and stall induced vibrations, wind turbine blades (22) comprising such devices (300), and methods (400) for reducing wind turbine vibrations when the wind turbine (10) is parked, especially during wind turbine installation and/or maintenance. A device (300) is configured to be arranged around a wind turbine blade (22) and comprises three or more air flow modifying elements (305) comprising a concave outer surface (323) configured to face away from a wind turbine blade (22). The device further comprises a supporting structure (310) configured to support the plurality of air flow modifying elements (305). An angular distance (307) between adjacent air flow modifying elements (305) in cross-section is substantially constant.

Abstract: A system and method are provided for reducing vibrations and loads in one or more rotor blades on a rotor hub of a wind turbine when the rotor hub is in a locked or idling condition. An electronically tunable mass damper is attached to a fixed location on one or more of the rotor blades. The mass damper is maintained on the rotor blades during the locked or idling condition of the rotor hub. The method includes sensing movement of a mass component of the mass damper from vibrations or oscillations induced in the rotor blade. The mass damper is automatically tuned based on the sensed movements of the mass component by automatically varying an electrical characteristic of the mass damper.

Abstract: Systems and methods for providing power to a blade pitch system in a wind turbine are provided. A blade pitch system can include one or more motors configured to pitch one or more blades of a wind turbine and a power source. The power source can include a plurality of energy storage devices coupled in series. The plurality of energy storage devices can be configured to provide power to the one or more motors during a power loss event. The power source can further include at least one bypass current device configured to allow a bypass current to provide power from at least one energy storage device to the one or more motors. The bypass current can be a current that bypasses one or more failed energy storage devices in the plurality of energy storage devices.

Abstract: A method for reducing loads of a wind turbine includes determining an operational state of the wind turbine. The method also includes commanding a predetermined pitch event. Further, the method includes monitoring at least one operating condition of a pitch drive mechanism of a rotor blade of the wind turbine during the predetermined pitch event. If the operational state corresponds to a predetermined operational state and the operating condition(s) follows a pitch fault pattern during the predetermined pitch event, the method also include yawing a nacelle of the wind turbine away from an incoming wind direction.

Abstract: A method for reducing loads of a wind turbine includes determining a wind speed at the wind turbine. Further, the method includes determining an operational state of the wind turbine. The method also includes determining whether a rotor of the wind turbine is imbalanced beyond a predetermined threshold when the operational state corresponds to a predetermined operational state as a rotor imbalance beyond the predetermined threshold is indicative of a pitch fault in one or more of the rotor blades. In addition, the method includes yawing a nacelle of the wind turbine to a predetermined angular position when the wind speed exceeds a predetermined speed threshold and the rotor is imbalanced beyond the predetermined threshold.