Abstract: The application relates to an apparatus (100) for fatigue testing a wind turbine blade specimen (10), and to a method using such an apparatus (100). The apparatus (100) comprises first and second support assemblies (120, 130) and an actuator (140) for cyclically deflecting the specimen (10) in a first transverse direction. The first and second support assemblies (120, 130) comprise first and second holders (121, 131) for holding first and second ends (12, 14) of the specimen (10), respectively, such that the longitudinal direction (16) of the specimen (10) extends between the first and second holders (121, 131). The first and second support assemblies (120, 130) are arranged such that the first and second holders (121, 131) are rotatable about a second transverse direction perpendicular to the first transverse direction and to the longitudinal direction (16) of the specimen (10).

Abstract: A method of repairing erosion on a wind turbine blade while on a wind turbine includes placing a scanning device on an erosion zone. The device scans the erosion zone to gather an image and/or digital data. A printing system deposits a material according to the image and/or digital data. The repair system may include a frame such that scanning and/or depositing are with respect to the frame. A processing system interprets the image and/or digital data and produces an instruction file. Depositing the material may include depositing the material according to the instruction file. An unmanned aerial vehicle may be operated to position at least one of the scanning device and the printing system on the wind turbine blade. Alternatively, a rope/wire system may be operated to lower at least one of the scanning device and the printing system along the wind turbine blade.

Abstract: A method of making a wind turbine blade comprises stacking a plurality of strips of fibre-reinforced polymeric material one on top of another to form a stack of strips (40); strapping the stack of strips together by means of at least one strap (41) made from a fibrous material, and thereby forming a strapped stack; infusing the strapped stack with resin; and curing the resin to form an elongate spar structure in which the at least one strap (41) is integrated with the stack of strips.

Abstract: A modular wind turbine blade is described. The blade has at least a first blade module and a second blade module connected to end to end. An interface is defined between the respective modules. The blade further comprises at least one longitudinally extending spar structure that forms part of the outer shells of the first and second blade modules when the modules are connected. The or each spar structure is substantially continuous and extends across the interface between the first and second blade modules when the modules are connected. The or each spar structure is integrated with the first blade module and the spar structure is folded or coiled to facilitate transportation of the module. The second blade module includes channels defined in the outer shell for receiving the or each spar structure when the modules are connected. In this way the spar structures also form part of the outer shell of the second module.

Abstract: The present invention relates to control of wind turbines in a situation where a fault condition is detected. Control of a wind turbine is described where a control trajectory and a safe-mode trajectory are calculated based on the current operational state of the wind turbine. If the fault condition is detected the wind turbine is controlled using the safe-mode trajectory, otherwise, the normal operation of the wind turbine is continued where the wind turbine is controlled using the control trajectory.

Abstract: A method and apparatus (14) for assembling a reinforcement web (12) for use with a wind turbine blade (10) are provided. A pre-formed flange structure (20) to be integrated with laminate layers (58, 60) to form the reinforcement web (12) is clamped into position against a mould end surface (76) using one or more locating clamps (16). The locating clamps (16) include first and second clamp blocks (80, 82) that are shaped to provide an external profile that avoids resin collection and bridging during resin injection molding, while allowing for clamping to be applied to the flange structure (20) with an easily assembled and disassembled removable engagement of the clamp blocks (80, 82). The locating clamp (16) prevents undesirable dislodgment of the flange structure (20) during the assembly process for the reinforcement web (12), and without necessitating the use of complex or expensive molding equipment or processes.

Abstract: A method of controlling noise produced by a wind turbine is disclosed. The wind turbine comprises one or more component cooling devices, and the method comprises: receiving one or more inputs indicative of noise generated by the one or more component cooling devices; determining the contribution of noise from the one or more component cooling devices to overall turbine noise based upon the one or more inputs; and modifying turbine operation based upon the contribution of cooling device noise to overall turbine noise and based upon turbine noise requirements. A corresponding wind turbine controller is also provided.

Abstract: A method for use in controlling a wind turbine generator based on a condition of a power converter or a component forming part of a power converter in the wind turbine generator. The method comprises determining a condition of the power converter or the component forming part of a power converter, then comparing the condition to a predetermined threshold and modifying an operational parameter of the wind turbine generator if the condition substantially equals or exceeds the predetermined threshold. In particular, the invention proposes the wind turbine generator is derated if the condition of the power converter or the component forming part of a power converter substantially equals or exceeds the predetermined threshold.

Abstract: A wind turbine comprising a tower, a nacelle, a rotor including a plurality of blades, an electrical generator operatively coupled to the rotor, and a control system. The control system comprises: a sensing system operable to output a signal indicative of the torsional oscillation frequency of the nacelle; a torsional damping module configured to monitor the torsional oscillation signal and to determine one or more blade pitch command signals for damping the torsional oscillation of the tower, and a filter module configured to receive the one or more blade pitch command signals as inputs and to output a respective one or more modified blade pitch command signals, wherein the filter module is configured to filter the one or more blade pitch command input signals to exclude frequency components greater than the torsional oscillation frequency. Aspects of the invention also relate to a method, a computer program software product and a controller for implementing the method.

Abstract: Equipment for handling a wind turbine component includes a lifting cable and a mounting block having a block main body with a cable passage and a pair of bushings coupled to the mounting block. Each bushing has an aperture defined by an aperture wall and the lifting cable extends through the aperture of each of the bushings. At least an outer region of the aperture wall forms a closed loop about the lifting cable and is substantially circumferentially continuous. This allows the lifting cable extending the bushings to move in a circumferential direction along the aperture wall relative to the bushings during use. A method of assembling such handling equipment and a method of using such equipment for handling a wind turbine component is also disclosed.

Abstract: There is presented a method for damping an edgewise vibration of a rotor blade of a wind turbine, wherein the method comprises measuring at the rotor blade a motion parameter of the edgewise rotor blade vibration, generating based on said motion parameter a blade pitch angle control signal, and damping the edgewise vibration of the rotor blade by pitching the rotor blade according to the blade pitch angle control signal, wherein the blade pitch angle control signal is arranged so that a resulting force on a rotor blade pitched according to the blade pitch angle control signal, in a direction of the edgewise vibration of the rotor blade in a coordinate system, which rotates with a rotor of the wind turbine, is opposite and proportional to the edgewise rotor blade vibration velocity.

Abstract: A bearing ring for a taper roller bearing defining a guiding flange (36, 110) and a raceway (112), wherein the bearing ring comprises a retainer element (77, 120, 124) that is removably engageable with the raceway. Embodiments of the invention also relate to a roller bearing assembly comprising such a bearing ring, and wind turbine arrangements incorporating such a roller bearing assembly.

Abstract: The invention relates to a method for controlling the operation of a number of airborne wind energy systems arranged in a wind energy park, where each airborne wind energy system comprising a wind engaging member being coupled to a ground station via a cable. The method comprises the determination of an operational parameter of each of the airborne wind energy systems, such as the flight trajectory, the cable tension, or the power production. A first airborne wind energy system is controlled according to a fault control mode if its operational parameter deviates more than a predetermined threshold parameter from the operation parameters of the other airborne wind energy system. The method further comprises operating one or more neighbouring airborne wind energy systems according to a safe control mode.

Abstract: A wind turbine includes a wind direction sensor, a yawing system, and a control system for yawing the wind turbine rotor relative to the wind. The control system measures a wind direction parameter by the wind direction sensor Over time a group of data sets is obtained and a wind direction offset is determined from the group of data sets which is used to adjust the wind direction parameter. The adjusted wind direction parameter is then used in the controlling of the wind turbine.

Abstract: A method and apparatus for assembling a wind turbine blade (10) including first and second outer shell portions (16, 18) and an internal web (12) are provided. An adhesive material (42) is applied to a top end (30) of the internal web (12) as well as the edges (62, 64) of the first outer shell portion (16) for connection to the second outer shell portion (18). Localized heat energy is applied to pre-cure the adhesive material (42) at the top end (30) of the internal web (12) before applying heat energy to fully cure all of the adhesive material (42) in the wind turbine blade (10). The pre-curing is performed by a removable localized heater device (72), and it assures that the integrity of the bond between the internal web (12) and the second outer shell portion (18) is maintained during the full curing of the blade (10), when temporary thermal deformation of the outer shell (14) sometimes occurs.

Abstract: Wind turbine pitch actuator mounting structure A mounting structure is described for attaching a pitch actuator to a hub of a wind turbine. The mounting structure has one or more legs each having a proximal end and a distal end, and a flexible intermediate portion between the proximal and distal ends. The mounting structure further comprises an actuator attachment portion for attaching to a wind turbine blade pitch actuator. The actuator attachment portion is arranged at the distal end(s) of the one or more legs. The proximal end(s) of the one or more legs are configured for attachment to a wind turbine hub. The flexible intermediate portion(s) of the one or more legs are configured to flex in use to absorb loads acting on the pitch actuator. The mounting structure therefore allows the pitch actuator to pivot in a first plane by virtue of the flexible legs.

Abstract: A method, controller, wind turbine, and computer program product are disclosed for processing and analyzing wind turbine operational data in a distributed data analysis system. An example method generally includes obtaining, at a first data analysis system, operational data from a plurality of wind turbines in a first wind power plant, determining adjustments to wind turbine operational parameters based on the operational data, pushing the adjustments to the first wind power plant, transmitting the operational data to a second data analysis system not located at the first wind power plant, and transmitting the operational data from the first wind power plant and at least a second wind power plant to a third data analysis system, wherein the third data analysis system comprises a global data analysis system.

Abstract: A method and control arrangement are disclosed for controlling power output of a wind power plant (WPP) including a plurality of wind turbine generators (WTGs). The method includes determining that overboosting is required for the WPP to meet a power demand at the WPP, and determining, for at least a first WTG of the plurality of WTGs, a corresponding amount of overboost capacity. The method further includes generating, based on the determined amount of overboost capacity, control signals causing the first WTG to increase its power output through overboosting to thereby fulfill at least a portion of the power demand.

Abstract: A wind turbine control unit comprising a control module configured to control an actuator system by outputting a first control signal, wherein the first control signal includes a current control sample value and a predicted control trajectory; the control unit further comprising an upsampling module configured to receive the first control signal from the control module, and to output a second control signal for controlling the actuator system, the second control signal having a higher frequency that the first control signal. The upsampling module calculates the second control signal in dependence on the current control sample value and the predicted control trajectory. The embodiments provide a more accurately reproduced control signal at a higher frequency that is suitable for onward processing which does not suffer from the problems of aliasing and delay that exist with conventional upsampling techniques.

Abstract: A method of identifying a fault in a system of gears in a wind turbine is provided. The method determines a first centre harmonic frequency amplitude according to vibrations of the system of gears and determines a plurality of sideband amplitudes of the first centre harmonic frequency amplitude. Further, the method calculates an average sideband amplitude from the plurality of sideband amplitudes and determines a value indicative of damage incurred by the system of gears based upon the first centre harmonic frequency amplitude and the average sideband amplitude. The centre harmonic frequencies may be harmonic tooth mesh frequencies and the value indicative of damage may be a ratio of the centre harmonic frequency amplitude and a difference between the centre harmonic frequency amplitude and the associated average sideband amplitude or vice versa. The method may analyse the value of any ratio obtained and use the ratio values to identify, and monitor the progress of, a fault.