Abstract: The present invention relates to controlling a wind turbine with an updated power coefficient. The updated power coefficient being adjusted by a degradation function which is determined in an iterative adjustment process. The wind turbine is controlled in partial load operation mode based on a tip-speed ratio (TSR) tracking scheme based on an estimated wind speed. The iterative adjustment process comprises operating the wind turbine to obtain a measurement set. The degradation function that represents the values of the measurement set is calculated and assigned to the mean operating TSR of the measurement set. The iterative process is continued until a difference between the selected TSR and the mean operating TSR is below a preset difference. A continuous degradation function for a range of the mean operating TSR value(s) is thereby obtained to determine an updated power coefficient to be used as the operating power coefficient.

Abstract: A controller for the yaw function is coupled with a yaw system for controlling the operation of yaw motors in the yaw function of a wind turbine. A control signal is provided to the controller that is reflective of a grid condition of an electric grid. The control signal is evaluated, and the controller selectively delays the yaw function based upon the control signal. In another embodiment, the yaw system includes brakes for the yaw motors that are coupled with an independent power supply. The controller selectively delays the yaw function if the brake power supply is not operational.

Abstract: A method of retrofitting a wind turbine having a tower and a first energy generating unit with a second energy generating unit. The method includes analyzing a first natural frequency of the tower relative to first rated operation frequencies of the tower having the second energy generating unit; when the first natural frequency lies within the first rated operation frequencies, modifying one or both the tower and the second energy generating unit so that the modified one or both the tower and the second energy generating unit have a second natural frequency and second rated operation frequencies that do not overlap; and replacing the first energy generating unit with the second energy generating unit.

Abstract: A method for handling a wind turbine component (20) is disclosed. The method includes providing a lifting system including a hoist cable (36) and an attachment assembly (38). The attachment assembly includes one or more removable ballast weights (48). The method includes positioning the attachment assembly near a working surface, removing at least some of the one or more ballast weights from the attachment assembly, and attaching a lifting tool (34) to the attachment assembly. The combined weight of the attachment assembly and the lifting tool is sufficiently greater than a threshold weight of the lifting system. The method further includes attaching a wind turbine component to the lifting tool and moving the wind turbine component using the lifting system. A lifting system is also disclosed. The lifting system includes a hoist cable, an attachment assembly, and a lifting tool.

Abstract: The present invention relates to a multirotor wind turbine comprising at least two rotor nacelle assemblies mounted to a support arrangement via respective yawing systems, and a toe angle control system for controlling the toe angles of the rotor nacelle assemblies with respect to the support arrangement; wherein the toe angle control system is configured to operate in a first mode in which the rotor nacelle assemblies are held at positive toe angles while the wind turbine is generating power in a main production mode; wherein the toe angle control system is further configured to monitor the operating mode of the wind turbine, and to switch to a second mode in which the yawing systems of the rotor nacelle assemblies are operated to reduce the toe angles of the rotor nacelle assemblies if an operating mode-based trigger condition has been met.

Abstract: A wind turbine blade comprising: a first blade portion having a shell that defines a suction side, a pressure side, a leading edge, and a trailing edge of the blade, the first blade portion further including a first blade portion end surface at one end of the first blade portion; a second blade portion having a shell that defines a suction side, a pressure side, a leading edge, and a trailing edge of the blade, the second blade portion further including a second blade portion end surface at one end of the second blade portion, wherein the first blade portion and the second blade portion are configured to be coupled together at the first and second blade portion end surfaces; and a connection joint for coupling the first and second blade portions together, wherein the connection joint includes: a first insert embedded in the first blade portion; a fitting integral with the first insert and projecting from the first blade portion end surface toward the second blade portion end surface; a second insert embedded

Abstract: A wind turbine nacelle configured for mounting on a wind turbine tower and housing a rotor-supporting assembly defining a rotation axis. The nacelle comprises a main unit arranged to be connected to a wind turbine tower and housing the rotor-supporting assembly. A crane is placed outside the main unit and connected directly to the main frame.

Abstract: Methods and systems for recycling a printed circuit board (PCB). The printed circuit board is exposed to a swelling agent that causes an epoxy matrix of the printed circuit board to swell and disintegrate into particles. The particles of epoxy are then separated from the printed circuit board, leaving behind reinforcing fiber and metal containing components thereof. These remaining components are separated from each other and recycled separately using suitable processes. The epoxy particles are also recovered, and may be reduced to a monomer for use in synthesizing new epoxy. The swelling agent includes a carboxylic acid, preferably formic acid, as an active ingredient.

Abstract: The present invention relates to controlling a wind turbine with a scaled power coefficient where the scaled power coefficient is determined in an adjustment process. In particular is disclosed control of a wind turbine in a partial load operation mode based on a tip-speed ratio (TSR) tracking scheme which based on an estimated wind speed determines a power setpoint. The disclosed adjustment process comprises setting a scaled power coefficient as a predetermined power coefficient multiplied by a scaling factor; adding a time-varying perturbation signal to the power setpoint; determining a transfer function from the perturbation signal to a power error; evaluate the frequency response of the transfer function over a time period to determine the scaling factor which minimizes the gain of the transfer function; and setting the operating power coefficient as the scaled power coefficient.

Abstract: The invention relates to a method for damping drive train oscillations of a VSM configured wind turbine. The method comprises determining a drive train damping power signal based on speed signal representing a generator speed, determining a power deviation based on a combination of a power reference for a desired power production, the drive train damping power-signal, a grid power supplied by the line side converter to the grid and a damping power, determining a virtual synchronous machine angle based on the power deviation so that the derivative of the virtual synchronous machine rotational speed is indicative of the power deviation, determining a converter reference for controlling the line side converter to generate the desired active power based on the virtual synchronous machine angle and a voltage reference for a voltage amplitude to be generated by the line side converter, and applying the converter reference to the line side converter.

Abstract: The invention relates to a wind turbine (2) comprising: a nacelle (8) provided on the top of a tower (12), a rotor including a hub (6) and a number of blades (4), a main shaft (16) configured to be driven by the rotor about a main axis and supported on the nacelle (8), a generator (28) having a generator rotor and generator stator, and a gear system (25) arranged to increase the rotational speed between said rotor and said generator rotor.

Abstract: A generator rotor assembly (42) comprises a cylindrical ring structure (46) defining a central hollow portion and arranged to rotate around a rotational axis. The cylindrical ring structure (46) comprises a plurality of permanent magnet packages (48) arranged coaxially around the rotational axis, the permanent magnet packages (48) comprising a plurality of coaxially stacked ring-shaped segmented layers (80), a plurality of tie rod holes (86) and a plurality of tie rods (54). The coaxially stacked ring-shaped segmented layers (80) comprise a plurality of contiguous segment sheets (82) arranged around the rotational axis to form the ring-shaped layer, the stacked layers (80) being staggered such that segment breaks between two contiguous segment sheets (82) in one of the layers are angularly offset with respect to segment breaks between two contiguous segment sheets (82) in an adjacent layer.

Abstract: The present invention relates to a partly assembled structure in the form of a structure comprising a wind turbine tower, a nacelle arranged thereon and a vibration damper attached to the nacelle for damping vibrations of the combined wind turbine tower and nacelle within a selected frequency range, wherein the vibration damper is operatively connected to a main shaft of the nacelle, or wherein the vibration damper is attached to the nacelle via a nacelle transportation interface. The present invention further relates to a method of constructing a wind turbine and a method for damping Vortex induced vibrations of the combined wind turbine tower and nacelle within the selected frequency range.

Abstract: A method of yawing a nacelle in a wind turbine having a yawing assembly comprising a drive-ring and a plurality of drives configured to exert a torque during movement along the drive-ring and thereby move the nacelle relative to the tower. The drive-ring is made of drive-ring segments joined in intersections. The method comprises defining a location for each intersection, defining a reference torque exerted by the drives when moving along the drive-ring, defining a reduced torque being lower than the reference torque, determining when a crossing drive moves across the location of an intersection, and to increase the lifetime, exerting the reduced torque by the crossing drive.

Abstract: Techniques for controlling the yaw of a wind turbine system by controlling a plurality of yaw drive actuators. When the yaw drive actuators are applying the same torque to all the motors, this can lead to some motors overspeeding, if the motor is not engaged when the yaw system is activated. Therefore, if the actual motor speed reference of a yaw drive actuator is higher than a specific motor speed reference, then an output signal to reduce the actual motor speed reference is applied to the yaw drive actuators with an actual motor speed reference higher than the specific motor speed reference.

Abstract: An electrical power generating assembly for a wind turbine. The electrical power generating assembly comprises a gearbox comprising a gearbox output shaft, a generator comprising a rotor that is coupled to the gearbox output shaft; and a current measuring module located between the gearbox and the generator. The current measuring module comprises: an electrical pickup mounted to the electrical power generating assembly, wherein the electrical pickup includes an electrical contact that engages with a slip ring associated with the rotor. The current measuring module further comprises: a first current measuring device mounted with respect to the electrical pickup to detect current flowing at least through the electrical pickup; and a second current measuring device mounted with respect to the electrical pickup to detect current flowing through at least a component associated with the gearbox output shaft.

Abstract: A rotor (1) for a wind turbine is disclosed. The rotor (1) comprises a hub (11) and at least one wind turbine blade (10), each wind turbine blade (10) being mounted on the hub (11) via a bearing unit (2). Each bearing unit (2) comprises a C-shaped bearing element (3) forming an inner ring and a T-shaped bearing element (4) forming an outer ring. The C-shaped bearing element (3) comprises a first bearing element part (12) and a second bearing element part (13). An interface (14) between the first bearing element part (12) and the second bearing element part (13) is positioned in such a manner that a third raceway pair (8) is formed between a protruding portion (5) of the T-shaped bearing element (4) and the first bearing element part (12) of the C-shaped bearing element (3) and the hub (11) or the wind turbine blade (10) is attached to the second bearing element part (13) of the C-shaped bearing element (3).

Abstract: A wind turbine rotor blade spar cap, the spar cap having a length and comprising: a stack comprising a plurality of layers of conductive material and at least one intermediate layer, wherein the layers of conductive material each have a length along the length of the spar cap in a first direction, wherein the intermediate layer is arranged between adjacent layers of the conductive material, wherein the intermediate layer includes a fibre fabric material having: a first edge extending in the first direction, a conductive portion having conductive fibres oriented in the first direction, a first border portion between the first edge and the conductive portion, the first border portion having a plurality of non-conductive fibres oriented in the first direction and no conductive fibres oriented in the first direction, and cross fibres oriented to cross the conductive fibres and the non-conductive fibres, and wherein the intermediate layer is bonded with the adjacent layers of the conductive material and is electri

Abstract: The invention relates to a spreader bar (1) for distributing a lifting force from a crane (2) onto a two lifting regions (3,4) f a load (5) to be lifted. The spreader bar comprises a frame (6) and first and second systems (7,8). Each system comprises a lifting pulley (9), a connector (10) for connecting the spreader bar to the respective lifting region via a main wire (11) guided by the lifting pulley, an actuator (15) for vertically moving the connector via an actuator wire (16), and a movably arranged suspension element (19) connecting the actuator wire and the main wire. A compensator (20) compensates for possible fluctuations in the vertical distance between the respective lifting region of the load and the spreader bar. Such fluctuations can be due to the crane or the load being located on a floating vessel. When the suspension element is engaged with a blocking element (23), the lifting force from the crane can be transferred to the main wire in order to lift the load.

Abstract: A method of forming a foundation (26) of a wind turbine (10) including a tower (12) having a base tower section (24), comprising: mounting a levelling apparatus (56) to an anchor cage (30), the anchor cage (30) including a plurality of anchor bolts (36) extending between an upper flange (34) and a lower flange (38), the levelling apparatus (56) being arranged between the upper and the lower flanges (34, 38); arranging the anchor cage (30) in an excavation pit (94); directing a cementitious material into the excavation pit (94) so that the upper flange (34) becomes at least partially embedded within the first cementitious material; allowing the cementitious material to cure to form a rigid body (28, 90); actuating the levelling apparatus (56) to raise the upper flange (34) from the rigid body (28, 90) into a levelled position; directing a grout material (32) into a space beneath the raised upper flange (34); and allowing the grout material (32) to cure to form a support layer.