Abstract: A horizontal axis wind turbine comprising a rotor having a plurality of blades, the rotor having a radius of at least 80 meters, the blades comprising: a root end and a tip end; a leading edge and a trailing edge; a shoulder between the root end and the tip end where a chord length defined between the leading edge and the trailing edge is at a maximum; wherein: Solr is at least 0.0140 at 0.7R; Solr is at least 0.0116 at 0.8R; Solr is at least 0.0090 at 0.9R; Solr being the combined radius specific solidity of the blades.

Abstract: Control of a multi-rotor wind turbine system. A local controller is arranged for each wind turbine module and implementing a local model predictive control (MPC) routine. A central controller is arranged to determine a set of operational constraints of the wind turbine modules. Based on a current operational state of the wind turbine module and the set of operational constraints, one or more predicted operational trajectories are calculated and used for controlling the wind turbine module.

Abstract: According to a first aspect of the invention, there is provided a wind turbine blade having a split blade configuration, comprising a first blade module defining an aerofoil profile and a second blade module defining an aerofoil profile; a damping module intermediate the first blade module and the second blade module; wherein the damping module comprises a first blade interface for joining to the first blade module and a second blade interface for joining to the second blade module. The damping module comprises a vibration damping unit. Beneficially, the invention provides a useful way in which to integrate motion damping functionality into a modular wind turbine blade.

Abstract: A method of determining rotor speed of a wind turbine. The method involves receiving angular velocity sensor data indicative of an angular velocity of the wind turbine rotor hub, provided e.g., by a gyroscope and receiving acceleration sensor data indicative of an acceleration of the rotor hub in at least one radial direction relative to an axis of rotation of the rotor hub. The method further involves determining first and second estimated rotational speeds of the rotor hub based on the respective angular velocity sensor data and acceleration sensor data. The method also involves determining a correction value based on a difference between the first and second estimated rotational speeds, and applying the correction value to the first estimated rotational speed to determine the true current rotor speed of the wind turbine.

Abstract: The invention relates to a device (100), a system (10) and a method for modifying the cross section of a tower section (1) of a wind turbine, wherein the tower section comprises a flange (4) located at an end (3) of the tower section having a plurality of through holes (5) spaced around its circumference for securing said tower section to another wind turbine section. The method comprises securing tensioning mechanism (14) to each of a pair of said plurality of through holes in the flange of the tower section, said pair of holes being generally opposed; and applying a tensile force between said pair of holes in the flange of the tower section.

Abstract: An arrangement includes a transmission, a pitch tube, and a fixation device configured to affix the pitch tube in the transmission. The fixation device is electrically insulated from the pitch tube. The pitch tube can be axially movable relative to the fixation device. The pitch tube can be fixed in a shaft or a rotatably-mounted planet carrier of the transmission by the fixation device.

Abstract: A method for assembling a wind turbine (10) having a first wind turbine component (20) with a first mounting interface (36) and a second wind turbine component (26) with a second mounting interface (34) includes positioning the second wind turbine component (26) relative to the first wind turbine component (20) such that the second mounting interface (34) is located a vertical distance above the first mounting interface (36), aligning the second mounting interface (34) to the first mounting interface (36), lowering the second wind turbine component (36) toward the first wind turbine component (20) to contact each other, and connecting the second mounting interface (34) to the first mounting interface (36). At any time during assembly when the second mounting interface (34) vertically overlaps the first mounting interface (36), the vertical distance between second mounting interface (34) and the first mounting interface (36) is maintained below a predetermined threshold (D).

Abstract: A pitch actuator for a wind turbine pitch system, the pitch actuator having an actuator rod, a drive end of which is defined by a clevis fork arrangement having first fork member and a second fork member that extend in a direction along a rod axis and terminate at a tip end. The first and second fork members define respective clevis openings for receiving a clevis pin therethrough, said clevis openings each having an opening perimeter profile comprising: a first perimeter section defined by a leading circular arc that is centred on the rod axis and oriented in the direction of the tip end of the fork members, the circular arc defining a nominal radius and a central angle of less than 120 degrees, and second and third flared perimeter sections that flank respective sides of the first perimeter section, each of which define an enlarged clearance zone with respect to at least part of an imaginary circle defined by the nominal radius of the first perimeter section.

Abstract: A blade access system (24) includes a support frame (28) configured to be coupled to a nacelle (14) of a wind turbine (10), the support frame (28) having at least one connecting member (42) configured to be selectively attached to and detached from at least one connecting member (40) included with the nacelle (14). A nacelle (14) includes at least one connecting member (40) configured to be coupled to at least one connecting member (42) of a support frame (28) of a blade access system (24). The at least one support frame connecting member (42) is configured to cooperate with the at least one nacelle connecting member (40) to define an unlocked position which is configured to allow the support frame (28) to attach to and detach from the nacelle (14), and a locked position which is configured to prevent the support frame (28) from detaching from the nacelle (28). A method of connecting the blade access system (24) to the nacelle (14) is also disclosed.

Abstract: A wind turbine generator nacelle (14) comprises a nacelle frame (44) having a first forward hub end and a second aft end. Dedicated transport fittings (46) are positioned at each of the ends of the nacelle frame (44). The fittings (46) are adapted to be engaged by transport frames (86) on first and second transport trailers (80) for supporting the nacelle frame (44) for transport by the trailers (80). A service platform (20) is mounted to the transport fittings (46) on the aft end of the nacelle frame (44) such that the service platform (20) is cantilevered off of the aft end of the nacelle frame (44).

Abstract: Operating a renewable energy power includes receiving a measurement signal indicative of a measured power characteristic of the plant at a point of connection to a power network; controlling the plant 12) according to a normal mode of operation to provide power by determining and dispatching power set points, the power set points being determined by: acquiring samples of the measurement signal at a sample rate; and determining the power set points based on the sampled measurements and a target level for the measured power characteristic; and monitoring the measurement signal to detect an undersampled oscillation of the measured power characteristic in the sampled measurements, and thereby detecting a control fault; and then controlling the plant according to a fault mode of operation.

Abstract: There is provided methods and systems for controlling a multi-rotor wind turbine generator having at least two rotor nacelle assemblies mounted to a support arrangement by a common yaw control system and each having a wind direction sensor mounted thereto configured to measure a wind direction relative to forward direction of its rotor nacelle assembly. The methods comprise the steps of measuring, for each rotor nacelle assembly, wind power parameter data over a plurality of relative wind directions, determining, based on the measured data, an optimum relative wind direction, either based on the average of two directions at which the parameter is maximum or on a combined data set, and controlling the yaw system accordingly.

Abstract: A wind turbine monitoring device for monitoring a wind turbine including a lightning sensor for detecting a lightning strike on a wind turbine blade includes a lightning parameter acquisition part configured to acquire at least one lightning parameter based on an output of the lightning sensor, a lightning level determination part configured to determine a level of the lightning strike based on the at least one lightning parameter acquired by the lightning parameter acquisition part; and an inspection control part configured to judge whether it is necessary to automatically inspect the wind turbine blade by at least one inspection unit for inspecting the wind turbine blade, according the level of the lightning strike determined by the lightning level determination part.

Abstract: A control network for a wind turbine system, the wind turbine system comprising multiple rotor-nacelle assemblies mounted on a support structure, the control network comprising: a respective local network associated with each rotor-nacelle assembly, each local network comprising multiple nodes; a central network that is connected to each local network, the central network comprising multiple nodes; and a synchronization device that synchronizes data transmission throughout the control network.

Abstract: A blade root cover segment suitable for fitting to a wind turbine blade to span a gap between the blade and a spinner cover. The blade root cover segment includes a first end and a second end and further includes a curved flange for abutting against a correspondingly curved surface of the wind turbine blade; a cover wall extending radially from the flange; and a tensioning band associated with the flange. The tensioning band includes a first end proximate to the first end of the blade root cover segment and a second end proximate to the second end of the blade root cover segment. The first end and the second end of the tensioning band include connection means for connecting with and applying tension between a like blade root cover segment. A blade root cover and a method of assembling a blade root cover are also provided.

Abstract: A wind turbine blade having at least two blade modules extending in the spanwise direction of the blade and being configured for connection end-to-end at a connection joint An electromagnetic shield is positioned in electrically conductive contact with the blade modules and extending across the connection joint in the spanwise direction.

Abstract: A method of operating a power generating system for a wind turbine connected to an electrical grid, the power generating system comprising a power generator, a converter, a transformer and a tap changer, the method comprising; monitoring a signal for detecting an over-voltage condition in the electrical grid which requires a reduction in the output voltage from the power generating system; initiating a convertor response mode configured to provide at least part of the required voltage reduction; and initiating a transformer response mode configured to provide at least part of the required voltage reduction; wherein the transformer response mode comprises operating the tap changer to adjust the output voltage from the power generating system.

Abstract: Techniques for controlling the yaw of a wind turbine system by controlling a plurality of yaw drive actuators. Based on a requested motor speed reference as an input signal, and a mean motor speed reference as a feedback signal, the method determines a required motor torque reference as an output signal for the plurality of yaw drive actuators. The plurality of yaw drive actuators rotates a nacelle or a structure comprising a plurality of nacelles such that an even load distribution is provided for the plurality of yaw drive actuators.

Abstract: The invention relates to a method for controlling power generation from a power plant which comprises power generating units such as wind turbine generators. The power generating units are controllable to produce power dependent on individual power set-points. The method comprises steps of obtaining desired target power set-points for one or more prioritized power generating units, determining final target power set-points for the one or more prioritized power generating units based on the target power set-points and an available power adjustment margin of the power plant which is available for adjustment of the power set-points of the one or more prioritized power generating units, and dispatching the final target power set-points to the prioritized power generating units.

Abstract: A method for tracking a gear tooth meshing angle of a gearbox of a wind turbine is disclosed. An initial reference virtual gear tooth meshing angle of the gearbox is selected, and an angular position of a high speed shaft and/or a low speed shaft of the gearbox is monitored. A virtual gear tooth meshing angle relative to the reference virtual gear tooth meshing angle is estimated, based on the monitored angular position of the high speed shaft and/or the low speed shaft and on information regarding topology of the gearbox. A number of full rotations of the high speed shaft and/or the low speed shaft which corresponds to an integer number of full periods of gear meshing of the gearbox is calculated, and the reference virtual gear tooth meshing angle is reset each time the high speed shaft and/or the low speed shaft has performed the calculated number of full rotations. The estimated virtual gear tooth meshing angle is applied to a periodic noise signal of the wind turbine.