Abstract: A method of assembling a tower section of a wind turbine tower is provided. The method includes arranging the tower section of the wind turbine tower in a horizontal orientation; transporting a damper unit to a position inside the tower section while the tower section is arranged in the horizontal orientation; and mounting the damper unit to the tower section, wherein the damper unit is configured to damp motions of the wind turbine tower. Further, a horizontal transport system is provided that is supported at least at one position by the tower section and that includes a movable part configured to support a damper unit and to transport the damper unit in a horizontal direction from a position adjacent to an end of the tower section to a position at or adjacent to a mounting position of the damper unit inside the tower section.

Abstract: Provided is a method for validating a predetermined digital certificate having a validation device, wherein the validation device stores approval information that specifies which digital certificates of a plurality of digital certificates are permissible digital certificates, and wherein the validation device further stores trust information which indicates a trust level of the permissible digital certificates. The method includes determining, while taking account of the approval information, whether the predetermined digital certificate is permissible for the planned use under the current conditions; and if it is determined that the predetermined digital certificate is permissible, determining the trust level of the predetermined digital certificate by taking into consideration the trust information for the planned use and the current conditions, is provided.

Abstract: A bearing protection arrangement of a journal bearing arranged between a housing and a rotary component of a wind turbine. The bearing protection arrangement includes a wind speed monitor arranged to monitor wind speed in the vicinity of the wind turbine and to generate a wake-up signal when the wind speed exceeds a pre-defined minimum; a mode switch module of a backup battery arranged to provide restart power to an auxiliary of the wind turbine, which mode switch module is adapted to switch the backup battery from a normal-power mode into a low-power mode to conserve sufficient restart power after low wind-speed conditions, and to switch the backup battery from the low-power mode into a normal-power mode in response to the wake-up signal. A wind turbine and a method of protecting a journal bearing of a wind turbine during standstill.

Abstract: Provided is a leading-edge protector for a wind turbine rotor blade, including a curved body shaped for attachment to the rotor blade along at least a section of its leading edge; a plurality of fins, each fin extending radially outward from the curved body and terminating in a blunt outer face; and a plurality of reinforcement bands, wherein a reinforcement band is attached to the blunt outer face of a fin. Also provided is a method of manufacturing such a leading-edge protector.

Abstract: Provided is a wind turbine including a generator enclosed in a generator housing, the generator housing including a rotating housing and a stationary housing, whereby the rotating housing is separated from the stationary housing by a first gap; a canopy mounted on a tower and including an electrical connection to a down conductor of the tower, wherein the canopy is separated from the generator housing by a second gap; a lightning current path provided by a plurality of brush assemblies mounted on the stationary housing, wherein a brush assembly includes a brush holder mounted on the stationary housing such that a carbon brush extends across the first gap to make electrical contact with the rotating housing; and an electrical connector extending across the second gap to electrically connect the brush holder to the canopy. Also provided is a method of providing a lightning current path for such a wind turbine.

Abstract: A wind turbine blade of a wind turbine, the wind turbine blade including a shell and a spar having at least one spar cap is provided. At least one of the at least one spar cap includes at least two longitudinal support structure elements, whereby at least two of the at least two longitudinal support structure elements are arranged adjacent to one another in a longitudinal direction of the wind turbine blade and at least one longitudinal support structure includes carbon fiber-reinforced plastic and at least one other longitudinal support structure includes at least one fiber-reinforced plastic different from carbon fiber-reinforced plastic.

Abstract: Provided is an arrangement and a method to detect an oil leakage between a first section and a second section of a hydraulic cylinder. A movable piston is arranged between the first and second section in a way that the piston changes position between the sections. The change in position is done in dependency of a difference between a first force, which acts at the first section on a first cross sectional area of the piston, and a second force, which acts at the second section on a second cross sectional area of the piston. The first section comprises hydraulic oil with a predefined first pressure, while the first force is calculated based on this pressure and based on the first area. The second section comprises hydraulic oil with a predefined second pressure, while the second force is calculated based on this pressure and based on the second area.

Abstract: Provided is a method for determining the rotational position of a rotor in a permanent magnet synchronous machine, wherein the stator includes windings for a first, second and third phase, including the steps: applying a first voltage pulse to the first phase, determining respective first measures for the current induced by the first voltage pulse in the second and third phase, selecting a first selected phase depending on the first measures for the current, wherein the first selected phase is either the second or the third phase, applying a second voltage pulse to the first selected phase, determining respective second measures for the current induced by the second voltage pulse in the phases of the stator that are not the first selected phase, and determining the rotational position of the rotor depending on the second measures of the current.

Abstract: A method for transferring data blocks from a field device to a server, each data block including data describing an operation of the field device during a block time period is provided. The method includes setting a first and a second pointer delimiting a completed time period; and, until a predetermined transfer period elapses: transferring the data blocks having a block time period that is later than the second pointer to the server in a chronological order; and if all data blocks having a block time period that is later than the second pointer have been transferred to the server, transferring the data blocks having a block time period that is earlier than the first pointer to the server in an anti-chronological order. Data blocks can efficiently and reliably be transferred to the server.

Abstract: A test arrangement for fatigue testing a wind turbine blade, including a floor-mounted test rig having a fixing device for fixing the wind turbine blade to the test rig and an excitation assembly for exciting the wind turbine blade at a test frequency, wherein the test rig includes a liquid tank having a chamber containing a predefined liquid, wherein the liquid in the liquid tank has a resonance frequency depending on the amount of liquid in the liquid tank and the chamber geometry is provided.

Abstract: A hatch arrangement with at least one slidable hatch for closing an opening in a floor of a wind turbine including a first guiding device fixedly mountable to the floor and a second guiding device pivotably mountable to the floor, a first coupling means to guide the slidable hatch along a first guidance path in the first guiding device and a second coupling means to couple the slidable hatch at least pivotably to the second guiding device, wherein the slidable hatch is coupled to the first guiding device at a first position and to the second guiding device at a second position, wherein a movement of the slidable hatch from a closed position along the first guidance path results in a pivoting movement of the second guiding device and in a movement of the slidable hatch to an open position and vice versa is provided.

Abstract: Provided is a rotor for a wind turbine, including: a blade, a hub, a pitch bearing being configured to support the blade rotatably about a longitudinal axis of the blade and relative to the hub, and one or more metal arcs for conducting a lightning current from the blade to the hub, the one or more metal arcs including: a first arc portion electrically and mechanically connected to the blade, a second arc portion electrically and mechanically connected to the hub, and a bent portion connecting the first and second arc portions. The metal arcs being configured such that, when the blade rotates relative to the hub, the first arc portion is shifted relative to the second arc portion and a length of the first arc portion is reduced or increased at the expense of an increase or decrease of a length of the second arc portion.

Abstract: Provided is a method of manufacturing a pultruded strip for an elongate structure. The method includes the step of: providing a pultrusion apparatus including at least a pultrusion die through which a plurality of fibers are pulled to be soaked in a resin, and changing the conduction properties of selected points along the plurality of fibers upstream the pultrusion die.

Abstract: Provided is a rotor blade of a wind turbine, wherein the rotor blade includes a trailing edge section with a trailing edge and a leading-edge section with a leading-edge, a root section with a root and a tip section with a tip, a shell which defines the outer shape of the rotor blade and a cavity which is confined by the shell, and a lightning protection system with an internal down conductor extending from the root section of the rotor blade to the tip section of the rotor blade, wherein the internal down conductor is connectable at the root section to a grounding system of the remainder of the wind turbine and at the tip section to at least one tip lightning receptor which is positioned at the surface of the rotor blade. In addition, the rotor blade comprises an electrically insulating tip part.

Abstract: Provided is an alignment tool for a cutting arrangement including a cutting apparatus with a cutting edge for treatment of a workpiece, especially a rotor blade of a wind turbine, in which the alignment tool includes at least one fixation means for fixing the alignment tool to the workpiece and at least one guiding structure to guide the cutting edge of the cutting tool.

Abstract: An alignment device for aligning multiple beams for a spar cap of a wind turbine blade of a wind turbine with respect to each other is provided. The alignment device includes a support plate, which is configured so that the multiple beams can be placed on a top side of the support plate, two limit stops, which are configured to partially enclose the multiple beams, at least one bending apparatus attached to the support plate and configured to bend the support plate, a vibration apparatus attached to the support plate and/or the at least one bending apparatus, whereby the vibration apparatus is configured to vibrate the support plate and/or the bending apparatus, so that the multiple beams become aligned with respect to each other is provided. A method for aligning multiple beams for a spar cap of a wind turbine blade of a wind turbine is also provided.

Abstract: A method of manufacturing a product including at least two carbon parts including the step of: manufacturing a first carbon part, manufacturing at least a second carbon part, providing on a surface of one of the first carbon part or second carbon part a plurality of protrusions including a carbon resin, joining together the first carbon part and the second carbon part in such a way that the plurality of protrusions is interposed between the first carbon part and second carbon part for providing physical and electrical connection is provided.

Abstract: A control system for stabilizing a floating wind turbine is provided. The control system includes a measuring device configured for measuring a wind field and a wave field, a determining device wherein the determining device is configured for determining an excitation frequency spectrum of the floating wind turbine on the basis of the measured wind field and/or the wave field and/or a current floater pitch angle of the floating wind turbine, and wherein the determining device is further configured for determining a balanced state of the floating wind turbine, wherein in the balanced state a natural frequency is outside of the excitation frequency spectrum and/or the current floater pitch angle is equal to a pre-defined floater pitch angle. The control system further includes an adjustment device which is configured for manipulating the current floater pitch and/or the natural frequency until the balanced state is met.

Abstract: Provided is a safety stop valve arrangement of a hydraulic blade pitch system of a wind turbine, including an accumulator arrangement connected over a hydraulic line to a piston of the hydraulic blade pitch system; a redundant set of safety valves arranged between the accumulator arrangement and the piston; a small-orifice restriction nozzle arranged to determine a first rate of hydraulic fluid flow in response to a safety stop input; at least one speed-select valves arranged; and at least one large-orifice restriction nozzle arranged to determine a second rale of hydraulic fluid flow in response to a positive rotor acceleration input, wherein the second rate of fluid flow is faster than the first rate of fluid flow. A safety stop assembly of a wind turbine with hydraulic blade pitch systems and a method of performing a safety stop sequence is also provided.

Abstract: Wind turbine comprising a tower (2) bearing a nacelle (5) and a rotor (3) with a plurality of rotor blades (4) and an active noise reduction device (7), wherein the active noise reduction device (7) comprises at least one actuator (8), at least one unsteady pressure sensor (9) adapted to produce an output signal corresponding to a turbulent flow condition during operation of the rotor blade (4), at least one noise sensor (10) adapted to produce an output signal corresponding to a noise generated by the rotor blade (4) at the location of the noise sensor (10), and a control unit (11), wherein the unsteady pressure sensor (9) and the actuator (8) are arranged on at least one of the rotor blades (4) and the noise sensor (10) is arranged at the nacelle (5) and/or at the tower (2), wherein the control unit (11) is adapted to control the actuator (8) in dependence of the output signals of the unsteady pressure sensor (9) and the noise sensor (10) to emit an anti-noise signal at least partly reducing the noise gener