Fos4x Gmbh

Technische Universitat Munchen

Thales Management & Services Deutschland Gmbh

Mathias Müller

Thorbjörn Buck

Rolf Wojtech

Lars Hoffmann

Florian Rieger

Matthias Schubert

Thomas Schauss

Fabian Zelenka

Sascha Kienitz

Markus Schmid

Thomas Grübler

Manuel Mai

Mathias Schubert

Benjamin Zorn

Martin Glück

The invention relates to an acoustic emission sensor (). The acoustic emission sensor comprises an optical resonator () having a sensor region () configured for reflective operation; an optical waveguide () which is optically coupled to the optical resonator (); a light source () which is optically coupled to the optical waveguide () to apply light to the optical waveguide (); and a detection device () which is optically coupled to the optical waveguide () to detect light from the optical resonator (). The sensor region () of the optical resonator () comprises a coupling device () for mechanically coupling to a solid measurement object (). The coupling device () comprises a first coupling element () for transmitting an acoustic emission signal between the sensor region () and the solid measurement object (), and at least one second coupling element (). The second coupling element () is configured to position the coupling device () on the solid measurement object (), and/or the second coupling element () acts as a filter for the acoustic emission signal.

Acoustic emission sensor having at least two mechanical coupling elements

Embodiments of the invention describe a method for ascertaining a value of an ice buildup quantity on at least one rotor blade () of a wind turbine () and to the use thereof. The method has the steps of ascertaining a base value (G) for at least one natural frequency of the rotor blade when vibrations are excited in an ice buildup-free state; ascertaining a shift base factor for shifting the at least one natural frequency relative to the ice buildup-free state in the event of an ice buildup quantity which is increased by a specific value; detecting a measurement value or a measurement value curve of a measurement variable which is suitable for determining the current natural frequency of the rotor blade (); determining the current natural frequencies of the rotor blade (); and deriving a current shift factor by comparing the current natural frequencies with the base value (G), comparing the current shift factor with the shift base factor, and deriving a value for the ice buildup quantity using the comparison.

Method for ascertaining a value of an ice buildup quantity on at least one rotor blade of a wind turbine, and use thereof

There is provided a fiber-optic pressure sensor (), which includes a waveguide () having an end, an optical deflection unit () connected to the end of the waveguide (), and a sensor body () at which an optical resonator () is formed by way of a diaphragm (). The waveguide () and/or the deflection unit () is/are attached to the sensor body () by way of a curable adhesive or a solder connection.

Fibre-optic pressure sensor having an optical resonator and a method for pressure measurement

A clamping device () for a light guide () is provided. The clamping device () includes a carrier structure having a first securing element () for securing the light guide () in a first position (), and a second securing element () at a distance from the first securing element () for securing the light guide () in a second position (), wherein the first and second positions () have a first distance () in a longitudinal extension of the light guide (). Further, an intermediate carrier () having a first surface () on which the first and second securing elements () are attached in respective securing positions (), and an opposing second surface (), which can be applied to a measurement object, is provided. Hereby, a second distance () of the securing positions () of the securing elements () on the intermediate carrier () is greater than the first distance () in a longitudinal direction of the light guide ().

Light guide clamping device, fiber optic sensor and production method

Embodiments describe a method for predicting the accumulation of ice on a rotor blade () of a wind turbine () and the use thereof. The method comprises defining an upper threshold value (So) and/or a lower threshold value (Su) for a system variable (S) which is associated with the mass of the rotor blade () and/or with the mass of an ice attachment () of the rotor blade (); acquiring system variable data during an acquisition time period (T); carrying out a compensation calculation of the curve profile for a prediction time period (&#x394;t', &#x394;t&#x2032;, &#x394;t&#x2032;) from the system variable data which were acquired during a partial time period (&#x394;t, &#x394;t, &#x394;t) of the acquisition time period (T) in order to obtain a prediction curve (N, N, N); carrying out at least one further compensation calculation of the curve profile for a further prediction time period (&#x394;t&#x2032;, &#x394;t&#x2032;, &#x394;t&#x2032;) from the system variable data which were acquired during another partial time period (&#x394;t, &#x394;t, &#x394;t) of the acquisition time period (T) in order to obtain a further prediction curve (N, N, N); determining whether or not the upper threshold value (So) will be exceeded by one or more of the prediction curves (N, N, N) in future and/or whether the lower threshold value (Su) will not be undershot by one or more of the prediction curves (N, N, N) in the future; and outputting the result of the determination; and outputting the result of the determination.

Method for predicting the accumulation of ice on a rotor blade of a wind turbine and the use thereof

A sensor patch () is provided that includes a light guide () having a sensor element (). Further, the sensor patch () includes a carrier structure having a first fastening element () for fastening the light guide () at a first position (), and a second fastening element () that is spaced apart from the first fastening element () for fastening the light guide at a second position (), wherein the sensor element () is arranged between the first position () and the second position (), an intermediate carrier () having a first surface (), on which the first and second fastening elements () are mounted at respective fastening positions (), and an opposing second surface () that can be mounted on a measurement object, and a covering element () arranged on the intermediate carrier () and connected thereto. The covering element () has together with the intermediate carrier () a cross-sectional dimension, which is oriented approximately perpendicular to a longitudinal extension of the light guide (), in such a way that the light guide () extends in the neutral fiber () of the sensor patch ().

Sensor patch and method for producing a sensor patch

A method for the individual pitch control of the rotor blades of a wind turbine is provided herein. In some embodiments, the method includes measuring an acceleration by an acceleration sensor in a rotor blade of the wind turbine; high-pass filtering of a signal of the acceleration sensor in order to determine a time-variant variable; and setting the pitch of the first rotor blade of the wind turbine using the time-variant variable, the pitch setting being part of an individual pitch control.

Method for the individual pitch control of rotor blades of a wind turbine, and wind turbines

The invention discloses an apparatus for measuring the torsion between a first point () and a second point () of a test object (), said second point being spaced apart from the first point. The apparatus comprises the following: a source of polarized light, comprising a polarizing light source () that emits polarized light, or a polarizer () that is connected to a light source () by way of an optical feed; a first optical fibre () that is optically connected to the Output of the polarizing light source () or to the Output of the polarizer () and that is fastened to the test object () at the first point () and at the second point () in such a way that a torsion of the test object about a torsion axis causes a change in the angle of rotation of the first optical fibre from the first point in relation to the second point, and a second polarization-maintaining optical fibre (), that is connected to the first optical fibre () at the second point () or downstream of the second point () in relation to the light path Coming from the source, for supplying the light to a measuring device (), wherein the distance between the first point () and the second point () of the test object () is greater than or equal to 5 metres, or greater than or equal to 7 metres, or greater than or equal to 10 metres, and the first optical fibre () comprises a non-polarization-maintaining, bending-insensitive fibre.

Apparatus and method for measuring the torsion of a test object

A method for monitoring a wind turbine is described. The method comprises measuring acceleration by means of a fiber-optic acceleration sensor in a rotor blade of the wind turbine; opto-electronically converting an acceleration signal of the fiber-optic acceleration sensor; and filtering the opto-electronically converted acceleration signal by means of an analog anti-aliasing filter.

Method for monitoring a wind turbine, method for identifying ice on a wind turbine, acceleration sensor for a rotor blade, rotor blade comprising an acceleration sensor, and profile for a rotor blade

The present invention relates to a method for compensation, for example, for temperature compensation of a fiber optic measurement system designed for determining a mechanical quantity. First and second fiber Bragg gratings have a respective Bragg wavelength, wherein the fiber Bragg gratings are irradiated with primary light. After applying a mechanical quantity to the first and second fiber Bragg gratings, the Bragg wavelengths of the fiber Bragg gratings are changed by the mechanical quantity. Filtering of the first and second secondary light, said first and second secondary light is effected from the primary light and modified by the Bragg wavelength of the fiber Bragg grating depending on the mechanical quantity by use of an optical filter device follows, in such a way that the Bragg wavelength of the first fiber Bragg grating lies in the region of the rising filter gradient of the optical filter device and the Bragg wavelength of the second fiber Bragg grating lies in the region of the falling filter gradient of the optical filter device. After determining the intensities of the filtered first and second secondary light, they are compared, whereupon the mechanical quantity is determined from the intensity comparison.

Method for compensation of fiber optic measurement systems and fiber optic measurement system

A method for the adjustment of an optical measurement system comprises providing an optical measurement system, which comprises, as optical elements, a beam splitter; a first photo sensor, exposed by a first partial beam from the beam splitter; an optical filter; a second photo sensor, arranged downstream of the optical filter, exposed by a second partial beam from the beam splitter. Additionally, the angularity and relative position between multiple optical elements is designed to be adjustable. The method further comprises providing a device for generating a difference signal from the two photo sensors; providing a light source with periodically varying polarization; irradiating the light in the beam splitter, so that the two respective photo sensors are exposed by a partial beam; generating a difference signal of the output signals of the photo sensors; varying the position and/or angularity of at least one optical element, and observing the difference signal, determine the combination of angularity/position of the elements where a minimum difference signal is achieved, and configuring the angularity of the optical elements to the determined values. Further, a corresponding system is proposed.

Optical measurement system with polarization compensation, and corresponding method

A method for state monitoring of a rotor blade of a wind turbine is described. The method comprises: measuring an acceleration of the rotor blade with a first signal, wherein the acceleration is measured at a first position at a predetermined distance from the rotor blade root in at least one direction comprising a first directional component orthogonal to the axis of the rotor blade, measuring a strain of the rotor blade with a second signal, wherein the strain is measured at a second position disposed in the area of the first position to the rotor blade root, determining a first positional change at the first position on the basis of the acceleration, determining a first value corresponding to the rotor blade stiffness or to the rotor blade elasticity by means of calculation on the basis of the first positional change and the strain, and determining the rotor blade state from the first value.

Method and device for monitoring the state of rotor blades

The present invention provides a method for installing at least one sensor device within a rotor blade of a wind turbine. A first substantially planar light beam is emitted in the interior of the rotor blade. Finally, at least one second substantially planar light beam is emitted in the interior of the rotor blade, wherein the plane of the first planar light beam is oriented at a predetermined angle to the plane of the second planar light beam. Further, the planes of the first and second planar light beams are aligned on the blade flange of the rotor blade. At least one sensor device is subsequently aligned in reference to the planar light beams.

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Munich, Germany

Mathias Müller