Abstract: The present disclosure is related to a method and a measuring device adapted for determining a rotational position of at least one rotor blade of a wind turbine. The method includes a step of measuring a gravity induced blade moment of the at least one rotor blade. Then, an actual rotational position of the rotor blade is determined from the measured gravity induced blade moment.

Abstract: A method for monitoring a structural health of a wind turbine. The method includes transmitting, from a sensor to a controller, at least one monitoring signal indicative of a structural discontinuity, the sensor operatively coupled to a structural component of the wind turbine. A first notification signal is transmitted from the controller to a user computing device upon receiving the monitoring signal.

Abstract: A method for temperature calibration of a strain sensor for a rotor blade of a wind turbine is provided, the method including operating the wind turbine in a mode in which substantially no bending of the rotor blade due to wind occurs, repeatedly measuring gravitationally induced bending moments of the rotor blade for a plurality of temperatures measured at the place of the strain sensor, determining a temperature dependency of the strain sensor on the temperature, calibrating the strain sensor based on the determined temperature dependency of the strain sensor such that the temperature dependency of the strain sensor is compensated.

Abstract: A system is disclosed for monitoring and controlling the deflection of turbine blades of a wind turbine. The system includes a passive position detecting apparatus and a controller. The passive position detecting apparatus may be configured to acquire and transmit data relating directly to a position of at least one of the turbine blades. The controller may be configured to receive the data from the passive position detecting apparatus and compare such data to a known position reference to determine turbine blade deflection.

Abstract: A fibre optic sensor is embedded in an integral housing block formed by moulding or extrusion. The housing block has a mounting surface for attachment to a wind turbine component by adhesive or mechanical connection. In an arrangement where the sensor is to be isolated from strains on the component, the housing block may be mounted on the component by means of a smaller mounting portion, joining the mounting portion at a neck region.

Abstract: A rotor blade of a wind power plant, comprising a rotor blade connection for connection to a hub of the rotor of a wind power plant and a blade tip disposed at the opposite end of the rotor blade. In order to provide a rotor blade in which flexing can be detected with simple means, at least one electrical conductor is laid over the length of the rotor blade, wherein the electrical conductor begins at the rotor blade connection, extends in the longitudinal direction of the rotor blade and back to the rotor blade connection, and that there is provided a detector which detects the electrical resistance of the conductor and is connected to an evaluation device which evaluates the electrical resistance.

Abstract: A system and method provide a proactive mechanism to control pitching of the blades of a wind turbine to compensate for rotor imbalance during normal operation by pitching the blades individually or asymmetrically, based on turbulent wind gust measurements in front of the rotor, determined before it reaches the rotor blades.

Abstract: A method for cleaning the blades of a wind turbine using precipitation. The method includes determining the presence or absence of precipitation. In response to the determination of the presence of precipitation, adjusting the rotor speed to increase the speed of the blades and/or adjusting the variable pitch drive to increase the pitch of the blades. The combination of the increased blade speed and/or the increase blade pitch and the presence of precipitation facilitate the removal of debris from the blades by the precipitation.

Abstract: An example airfoil assembly includes an airfoil body extending between a leading edge, a trailing edge, a suction side, and a pressure side. The assembly further includes a first protective sheath, an indicator sheath, and a second protective sheath. The first protective sheath has an outer side and an inner side that forms a cavity for receiving at least a portion of the airfoil body. The inner side being bonded to the leading edge of the airfoil body. A portion of the indicator sheath is positioned forward the first sheath relative to the leading edge of the airfoil. A portion of the second protective sheath is positioned forward the indicator sheath relative to the leading edge of the airfoil.

Abstract: A wind turbine includes a rotor having one or more rotor blades, a pitch system for controlling the pitch angle of the one or more rotor blades, the pitch system having at least one pitch actuator, a pitch controller for generating pitch actuator control signals and sensor elements for establishing values of pitch performance parameters, and a compensation controller to compensate for disparities between the pitch actuator control signals and the values of pitch performance parameters, according to a control algorithm. The compensation controller is arranged to adjust parameters of the control algorithm of the compensation controller in dependency of the disparities.

Abstract: A sensor system for measuring aerodynamic loads acting on a wind turbine rotor blade is disclosed. The measured aerodynamic loads can be converted to an angle of attack of the resulting wind which flows past the moving rotor blade. The sensor is realised as a trailing edge flap which is elastically moveable relative the main part of the wind turbine blade. By measuring motion of the trailing edge flap or corresponding motions of components of the sensor system, the aerodynamic forces acting on the blade can be determined. Due to the relative small dimensions of the sensor flap and the relative small displacements of the flap, the sensor system only affects the aerodynamic properties insignificantly.

Abstract: The invention relates to wind energy systems. A wind energy system is provided having an insect sensor. The insect sensor is adapted for measuring the insect density in the air. Further, a method for operating a wind energy system taking into account the insect density in the air is provided. The wind energy system is curtailed during times with a high insect density. Hence, in periods following times with a high insect density, the wind energy system can be operated without the aero-dynamical performance of the rotor blades being spoiled by smashed insects.

Abstract: Systems and methods for monitoring wind turbine operation are disclosed. A method in accordance with one embodiment includes processing sensor data received from at least one strain gauge located on a wind turbine shaft, with a processor located on the wind turbine shaft. In particular embodiments, the method can further include providing power for the at least one strain gauge and the processor via a non-contact link between a first component located on the wind turbine shaft and second component off the wind turbine shaft. In further particular embodiments, the method can still further include receiving data from the processor corresponding to bending moments at the wind turbine shaft, and automatically identifying load remediation solutions for the wind turbine, based at least in part on the data received from the processor.

Abstract: A method of operating a wind turbine having rotor with at least one blade, includes sensing an icing hazard for the blade; and moving the at least one blade into a position to reduce the icing hazard.

Abstract: A high-efficiency turbine generates energy from a fluid flow, such as wind or water currents. The turbine has a central axis with a plurality of foils rotatable about the central axis in a general paddlewheel arrangement. Each of the foils has a foil axis parallel to the length of the foil and the central axis, and is rotatable about its foil axis. During operation of the turbine, each foil assumes an attack angle to the direction of the fluid flow with the attack angle dynamically controlled about the foil axis as the foil rotates about the central axis so as to maximize the foil's moment about the central axis.

Abstract: A wind turbine blade assembly includes at least one local load sensor disposed on and/or within a surface of the wind turbine blade and at least one active flow modification device disposed on and/or within a surface of the wind turbine blade and configured to alter the aerodynamics of the wind turbine blade in response to real time local load sensor measurements such that a difference between a current angle of attack and an optimum angle of attack on the wind turbine blade is substantially minimized.

Abstract: A monitoring system for at least one wind turbine includes at least one sensor disposed at the at least one wind turbine to detect wind friction at the at least one wind turbine. At least one controller is connected to the at least one wind turbine, and a monitor server is connected to the controller to change an operational status of the at least one wind turbine based on wind friction data received from the at least one sensor. A method of operation of at least one wind turbine includes continuously measuring data relative to wind friction at the at least one wind turbine via at least one sensor located thereat. The data is continuously compared to a predetermined wind friction threshold. A trend in the comparisons is evaluated, and the operational status of the wind turbine is changed via a monitor server based on a result of the comparison.

Abstract: Disclosed are methods for designing vanes that, in use, are expected to be exposed to vibratory loading, in particular rotor or stator vanes for aero engines or turbomachinery. A quantitative characteristic (modeshape) is used which is a measure of correlation between the excitation force to which the vane is to be subjected in use and a vibrational mode of the vane, corresponding to a characteristic frequency of the excitation. The modeshape of the first design is determined. Then the first design is modified to give a second design, by one or more of leaning, sweeping or twisting the blade design, or by altering the local shape of the design, or by altering the material of the design. Then the modeshape of the second design is determined. The design modification gives rise to a reduction in the forced response levels.

Abstract: A wind turbine blade with strain sensing functionality includes a surface structure, a block sensor unit including an optical sensor mechanism for sensing strain in the blade, and an intermediate connection plate positioned in between the optical sensor mechanism and the surface structure. The intermediate connection plate is adhesively connected to the surface structure and connected to the optical sensor mechanism. The modulus of elasticity of the intermediate connection plate is similar to or less than the modulus of elasticity of the surface structure. A wind turbine, block sensor unit and uses thereof are also contemplated.

Abstract: A wind turbine includes an electrical stall sensor configured on a pressure surface of at least one turbine blade at a location to detect backflow in a stall condition. The stall sensor includes a flap pivotally configured on the respective pressure surface so as to be moved from a first position towards a second position by backflow over the pressure surface during a stall condition. A sensor circuit responds to movement of the flap between the first and second positions and generates a corresponding electrical signal that indicates the stall condition.

Abstract: A method for condition monitoring a rotor of a wind energy plant includes the steps of measuring activity signals of the blades in the rotor and establishing one or more differential values between the activity signals of different blades. The one or more differential values are used for monitoring the condition of the rotor in the wind energy plant. A wind energy plant, a cluster of wind energy plants and use hereof is also contemplated.

Abstract: A method for optimizing the operation of a wind turbine is provided, the method comprising the steps of: (a) adjusting at least one control parameter of said wind turbine to a predetermined starting value; (b) measuring at least one response variable of said wind turbine and at least one further variable indicative of an ambient condition of the wind turbine; (c) repeating step (b) N times, wherein N is a predetermined integer, wherein said at least one control parameter is varied at each repetition; (d) determining a measured relation between the at least one control parameter with respect to the at least one response variable and the at least one further variable indicative of an ambient condition; (e) determining an optimized value of said at least one control parameter with respect to said response variable from said measured relation; (f) adjusting a set point of said at least one control parameter to said optimized value.

Abstract: The invention relates to a method and a device for monitoring the state of rotor blades on wind power installations. According to the invention, structure-borne noise is measured by means of at least one displacement sensor arranged on the rotor blade, the output signals of said sensors determine a frequency spectrum in an evaluation unit by means of suitable methods, the frequency spectrum is compared to reference spectra corresponding to defined states of damage and other particular states and stored in the evaluation unit, and the state of the rotor blade is determined therefrom. The aim of the invention is to provide a method and a device which enable existing local inner and outer damage, and other particular damage-causing states of the rotor blades, to be rapidly identified and evaluated, in order to take into account the effect thereof on the operation of the installation in an automatic manner.

Abstract: The invention relates to a method of monitoring the operation of a wind energy plant, wherein the operation comprises collection of blade-related operational data. Novel aspects of the method according to the invention comprises that, in predefined points on the blade, position indicators are arranged that can be used in a positioning system for identifying the position of the position indicators; and that the positions of the position indicators and hence the position of the predefined points are determined and collected as a part of said blade-related operational data.

Abstract: Method and apparatus for providing a turbofan blade 40 adapted to initiate and control a boundary layer transition at a side surface of the blade 40 during operation as a component in a turbofan assembly 35. The turbofan blade 40 includes a leading edge 55, a trailing edge 58, and two side surfaces including a high-pressure side surface 49 and a low-pressure side surface 52. At least one of the two side surfaces has an essentially smooth surface portion 61 located between the leading and trailing edges, and the essentially smooth surface portion is interrupted by a surface deviation 64. The surface deviation is configured to fix a positionally unstable laminar to turbulent boundary layer transition 24 at a location toward the trailing edge from the surface deviation during operation of the turbofan blade in the turbofan assembly.

Abstract: A method for operating a wind power plant, in which the wind power plant (10) has a multiplicity of components, but at least one rotor (18) with at least one rotor blade (22) and a generator for converting the mechanical energy of the rotor (18) into electrical energy and possibly a tower (14) on which the rotor (18) is arranged. Counterforces which counteract forces acting on the component (22), particularly wind loads, can be introduced into at least one component during the movement of rotation of the rotary blade (22).

Abstract: A computer implemented method includes receiving condition information from a plurality of condition detection sensors coupled to a wind turbine and receiving wind turbine controller information. An anomaly detection algorithm is applied to identify maintenance activities for the wind turbine as a function of both the wind turbine condition information and the wind turbine controller information.

Abstract: A method for balancing a rotor of a rotary machine, wherein the rotor includes at least two rotor blades and a rotor shaft, includes receiving at least one measurement of either a load, an acceleration, or a displacement that pertains to at least one bending moment acting on the rotor shaft, determining at least one value of the at least one bending moment acting on the rotor shaft based, at least in part, on the received at least one measurement, and determining a pitch offset angle value of at least one rotor blade that facilitates reducing the at least one bending moment acting on the rotor shaft.

Abstract: The invention relates to a wind turbine comprising a rotor including one or more pitchable blades, and detection means for detecting edgewise oscillations in one or more of said blades. The wind turbine is characterized in that the wind turbine comprises control means for changing the pitch angle of one or more of the blades if the detection means detects edgewise oscillations in one or more of the blades, hereby damping or eliminating the edgewise oscillations. The invention further relates to a method for damping edgewise oscillations in one or more blades of a wind turbine and use hereof.

Abstract: High-temperature steam at 620° C. or higher is introduced to a reheat steam turbine 100, and a turbine rotor 113 of the reheat steam turbine 100 includes: a high-temperature turbine rotor constituent part 113a positioned in an area extending from a nozzle 114a on a first stage to a moving blade 115a on a stage where temperature of the steam becomes 550° C. and made of a corrosion and heat resistant material; and low-temperature turbine rotor constituent parts 113b connected to and sandwiching the high-temperature turbine rotor constituent part 113a and made of a material different from the material of the high-temperature turbine rotor constituent part 113a.

Abstract: A method for determining the evolution of torque of at least one rotatable shaft and the resulting fatigue damage to different power train components is provided for design and/or maintenance operations in a wind turbine that comprises the steps of determining torque (Tg) at a high speed shaft of the power train; determining moment of inertia (Ig) at the high speed shaft; determining angular acceleration (?g) at the high speed shaft; and determining torque (Tr) at the low speed shaft of the power train through the formula Tr=(Tg?Ig ?g)·i. A rainflow-counting algorithm may be applied to the value of the torque (Tr) at the low speed shaft for determining the number of cycles at ranges of torque for every torque mean value.

Abstract: An object of the present invention is to provide a microchip whereby, when chemical analysis is conducted, a specimen liquid can be directly collected and weighed without using any collecting and weighing devices. The present invention provides a microchip for analyzing liquid samples, which has a measuring structure for weighing and collecting a given amount of a specimen liquid within a range of 0.05 to 10 ?l from an excessive amount of the specimen liquid which was introduced in the chip, wherein the measuring structure is located at the upstream side of an analysis element for analyzing a target substance in the specimen liquid inside the microchip.

Abstract: The invention relates to a method for testing a rotor blade (13.1) of a wind power plant (1), which sweeps across a rotor blade surface to be covered during operation of the wind power plant, comprising the following steps: emitting a target light beam (20), in particular a target light beam having a power density, in a direction of the target light beam onto the rotor blade surface to be covered; detecting a possible reflection of the target light beam by a detection device at a point of incidence (16) on the rotor blade; electrically controlled emission of a measurement laser beam (21) which has a power density that is larger than the power density of the target light beam immediately after detection of the reflection at the point of incidence so that the rotor blade is heated at the point of incidence; measuring a temperature distribution at the point of incidence; and repeating the steps (a) to (d) for several points of incidence.

Abstract: A device for adjusting the pitch angle of propeller blades for a model engine including at least one rotor, the blades extending radially on the surface of the rotor to form a propeller. It includes a tool-holder including a base designed to be fixed to a part of the outside of the engine housing and an upper part, the aforementioned upper part being fitted with means of support movable horizontally along a longitudinal axis (XX?), the aforementioned axis being parallel to the main axis of the model engine, contactless means of optical measurement, the aforementioned means of measurement being mounted on the movable means of support by using means of travel in rotation around an axis of rotation, the aforementioned axis of rotation being the blade's axis of rotation.

Abstract: A rotor blade 1 includes a main blade section 10, and an extension flap 20. The extension flap 20 is moveable relative to the main blade section 10. At least the main blade section 10 and the extension flap 20 form an airfoil lifting surface of the blade. A dimension of the airfoil lifting surface is variable by moving the extension flap 20 relative to the main blade section 10.

Abstract: Techniques and apparatuses for wind turbine component fatigue load measurement and assessment are disclosed. In one embodiment the component is a tower, fore-aft and side-to-side signals from a two-axis accelerometer attached to a bedplate of a wind turbine are used to measure tower fatigue loads. A yaw axis azimuth position signal can also be used for tower fatigue load measurement and assessment.

Abstract: A system and method for a pressure based load measurement system are provided. The system includes two pressure orifices arranged on a top surface and a bottom surface of an airfoil. The pressure differential between these two points is determined and an estimate of the aerodynamic load generated by the airfoil is determined from a linear correlation between pressure differential and load. The location of the orifices may be optimized using analytical or experimental techniques and a least squares empirical curve fit may be used to fit the data collected.

Abstract: The device for detecting damage of a wind energy turbine of a wind energy turbine rotor blade, due to a lightning strike, comprises several magnetic or electric field sensors distributed along the length of a rotor blade of the wind energy turbine for measuring the magnetic or electric field concentration along the rotor blade and, an evaluation unit connected to the magnetic or electric field sensors for receiving the measured signals thereof, wherein damage of the wind energy turbine of the rotor blade caused by a lightning strike is calculated by the evaluation unit based on the measured concentration of the magnetic or electric field along the length of the rotor blade.

Abstract: The invention relates to a wind energy system comprising a tower, a nacelle attached to the tower, the interior of which can be entered, a rotor that is rotatable relative to the nacelle, with a hub, the interior of which adjoins the nacelle interior and is accessible from this via a connecting passage, and comprising a rotor stop mechanism, with which rotor rotation can be enabled in a released position and blocked in a locked position, wherein a warning device, which is controlled on the basis of the position of the rotor stop mechanism, and which can emit a warning signal against accessing the hub interior when the rotor stop mechanism is in the released position [sic—Translator].

Abstract: A wind turbine blade (1) incorporating an optical fibre (4) configured for structural monitoring of the turbine blade. The optical fibre comprises at least one strain sensor (5). One end of the optical fibre (4) is an output point, which is connected to a data processing device (3) configured to process signals from the strain sensor (5). The other end of the optical fibre is an alternative output point, which is also connectable to the data processing device, such that in the event of a breakage in the optical fibre, signals from the strain sensor are available from at least one of the output points.

Abstract: The invention relates to a wind turbine blade comprising one or more electric powered modules. The modules have power supply means converting an energy source to electrical power for said one or more modules, wherein said energy source is light beams transmitted to the power supply means in the blade structure and/or interior from an external light source. The invention also relates to wind turbine and a method for manufacturing a wind turbine blade.

Abstract: An impeller device may include a magnetic detecting element and a magnetic body, which is paired with the magnetic detecting element, for detecting a rotational position of a rotary impeller. The rotary impeller is formed with a bottomed recessed part having an opening into which one of the magnetic detecting element or the magnetic body is inserted, and the opening of the recessed part is sealed with resin injected by insert molding so that the one of the magnetic detecting element and the magnetic body is buried in the rotary impeller. The magnetic detecting element and the magnetic body are capable of facing to each other through a bottom face of the bottomed recessed part.

Abstract: A method for monitoring blade frequencies of a wind turbine and a monitoring system for performing the method are provided. An accelerometer or G-sensor is placed into a nacelle of a wind turbine and thereby measuring the vibrations of the nacelle. To extract the vibration signals originating from each blade, the vibration signals are combined with the measuring signals from the azimuth angle sensor (rotating angle), which is normally used for pitch control. To further extract each blade frequency a Fast Fourier Transformation is used on the modulated G-sensor signals. To further monitor a severe and alarming change in each blade frequency, each blade frequency is compared to the other blade frequencies and an alarm is set when a given level is reached.

Abstract: A vibration-resistant wind turbine and process for operation is provided. The wind turbine has a rotor with at least two blades, each of which includes an inclinometer arrangement with at least two axes, and an evaluating unit. The evaluating unit determines the bending and/or twisting of the blade relative to the longitudinal axis of the blade on the basis of signals from the inclinometer arrangement for each blade during operation. Each rotor blade further has at least one liquid tank which is capable of receiving or transferring liquid from or to a liquid reservoir via a transfer mechanism in response to the determined bending and/or twisting of the rotor blades to reduce vibration caused by imbalances, thereby extending the service life of the wind turbine.

Abstract: A system for the structural monitoring of blades 1 on a wind turbine. Each blade 1 has respective optical fibre bragg grating sensors 5. The system has a number of input connectors, which connect to the strain sensors 5 of respective blades 1. A single output connector connects to a data processing device 3 which processes signals from the strain sensors 5. The input connectors each have a signal path to the output connector that is different in length to the signal path from the other input connectors, such that signals from a given blade 1 can be identified at the data processing device 3 by the time of arrival of the signals. The system has the advantage that the each of the blades 1, including the sensors attached to it or embedded within it can be identical and therefore interchangeable.

Abstract: A device for driving a first part of a wind turbine with respect to a second part of the wind turbine includes a driving element for engagement with the first part. The device also includes a driving unit including a housing to be fixedly connected to the second part, a motive generation means for generating motion of the motive element, and a motion transferring means for transferring the motion of the motive element to the driving element; and at least one slip coupling arranged between at least one of the motive element of the driving unit and the motion transferring means, the motion transferring means and the driving element, and within the motion transferring means, wherein the slip coupling is adjusted to slip if a torque acting on the slip coupling due to a movement force acting on the driving element exceeds a predetermined maximum torque.

Abstract: The invention concerns a method for operating a wind power plant (WEA), preferably before or during the performance of maintenance work on the wind power plant (WEA), wherein —at least one physical condition of the surroundings outside the wind power plant (WEA) induced by wind movement outside the wind power plant (WEA) is detected as an external physical condition, and/or at least one physical condition of a component of the wind power plant (WEA) influenced by wind movement outside the wind power plant (WEA) is detected as an internal physical condition; —the at least one external physical condition and/or at least one internal physical condition are evaluated; —the at least one external physical condition is compared with a predetermined reference value for the external physical condition, and/or the at least one internal physical condition is compared with a predetermined reference value for the internal physical condition; —depending on the comparison at least one warning message is generated, in partic

Abstract: An airborne mobile platform generally includes a plurality of rotating rotor blades operating in an airflow that forms a boundary layer on each of the rotor blades. At least one of the rotor blades includes a section that encounters the airflow that includes an unsteady subsonic airflow having at least a varying angle of attack. At least one of the rotor blades also includes one or more vortex generators on the at least one of the rotor blades that generate a vortex that interacts with the boundary layer to at least delay an onset of separation of the boundary layer, to increase a value of an unsteady maximum lift coefficient and to reduce a value of an unsteady pitching moment coefficient for the section.

Abstract: An aerodynamic device is provided for detection of physical conditions of wind turbine blade operation. One or more vibration sensors are mounted on the blades in an aerodynamic housing and configured to monitor a physical condition of the blades that varies in accordance with a vibration of the housing. A processor is operably coupled to the one or more vibration sensors. The processor may be configured to use the vibration frequency of a component of the blade to determine the physical condition of the blade, and generate a signal indicating the physical condition of the blade when determined.

Abstract: A system and method of providing noise control for a wind turbine are provided. The system includes at least one blade operably mounted on a wind turbine, and one or more sensors for receiving one or more signals relating to an operating characteristic of the wind turbine. A controller is configured for evaluating the signals to determine if they are outside a predetermined range. The system is configured to adjust operating characteristics and/or generate alarms if the signals are outside a predetermined range. The method includes the steps of receiving one or more signals from one or more sensors, determining if the signals are outside a predetermined range, and adjusting an operating parameter of the wind turbine or generating an alarm in response to the signals received from the sensors. The operating parameter can be adjusted to alter the amount of noise generated by the wind turbine.