WO2013045610A1

WO2013045610A1 - Device and method for detecting a distance value

Info

Publication number: WO2013045610A1
Application number: PCT/EP2012/069183
Authority: WO
Inventors: Jörg Lange; Hans-Jürgen Liesegang; Jochen Lorenscheit
Original assignee: Aktiebolaget Skf
Priority date: 2011-09-29
Filing date: 2012-09-28
Publication date: 2013-04-04
Also published as: DE102011083747A1; EP2766692A1; DE102011083747B4

Abstract

The invention relates to a device (200) for detecting a distance value between a first point (210) and a second point (220) on a component (160). Said device comprises, according to one embodiment, a support (230) which is mechanically fixed to the first point (210), a transmission component (270) which is mechanically fixed to the second point (220) and is mechanically coupled to the support (230) such that the transmission component (270) exerts a force onto the support (230) when the second point (220) moves in relation to the first point (210), perpendicular to the direction of extension (130) of the component (160), and a deformation sensitive sensor (390) is mechanically coupled to the support (230), said support (230) being designed to react, by deformation, to the force exerted by the transmission component (270). Said device (200) according to one embodiment can also, optionally, efficiently detect one or more distance values.

Description

Apparatus and method for detecting a distance value Exemplary embodiments relate to an apparatus and a method for detecting a distance value, for example on a rotor blade of a wind or tidal power plant or on a tower of a wind power plant.

In many areas of technology, hollow bodies are used as components for various reasons. Thus, for example, these have a lower mass and thus a lower weight in comparison to a configuration of solid material. Likewise, they can make it possible to arrange components, such as cables, sensors, actuators or other components, in their interior, thus accommodating space-saving and protected from environmental influences.

Hollow bodies are used in almost all areas of mechanical and plant engineering. They are used both for smaller and larger machines and plants, up to buildings. An example is thus wind turbines, which typically have a nacelle arranged on a tower, which in turn comprises a rotor, wherein the rotor accommodates at least one, often a plurality of rotor blades. Modern wind turbines often use three rotor blades. Both the tower and the rotor blades represent plant parts with a length along a direction of extension of the relevant plant parts of several tens of meters. These are subjected during operation to a multiplicity of forces, to which For example, the gravity and centrifugal forces, but also environmental forces include, such as acting on them air currents, gusts and storms.

A monitoring of a wind turbine with regard to the forces occurring is advisable for various reasons. Thus, for example, by monitoring the forces acting on the wind power plant or its components forces for the plant itself, for example in the form of overloads by gusts and other storms, also be detected, such as an orientation of the wind turbine to the prevailing winds, to achieve the highest possible degree of efficiency.

For example, in today's wind turbines an orientation of the nacelle, which is rotatably mounted to the tower, carried out to the prevailing wind currents, for example by means of various sensors which are mounted on the nacelle. There, however, they are in the lee of the rotors, which is why the rotors have an influence on the measurement results of these sensors. These sensors include, for example, anemometers and / or weather vanes. For example, the rotors generate turbulence and other turbulences, so that the readings taken by the sensors located on the nacelle often do not correspond to the real conditions.

Also, these sensors are often only suitable to set, for example, a pitch angle of the rotor blades (English: Pitch Angle). A control of the angle of attack is not only possible to control the output of the wind turbine concerned, but also allows a forced shutdown of the wind turbine, if the forces acting on the wind turbine forces by gusts or storms exceed certain thresholds, so that damage to the wind turbine is to be expected. For this purpose, then the rotor blades can be rotated, for example by a certain angle, typically 90 °, so that they offer the wind a smaller attack surface.

Rotor blades thus have, for example, a complex geometry whose design is to be optimized in such a way that, on the one hand, air resistance is as low as possible, but on the other hand, a conversion of the kinetic energy of the air flow into rotational movement can take place as efficiently as possible. At the same time an attempt is made to perform the rotor blades as easily as possible and still torsionally.

Due to these sometimes very different objectives, torsions and other mechanical loads often occur both in the area of the rotor blades and in the area of the tower due to the prevailing environmental conditions. Due to the above-described problem of mounted on the gondolas sensors it also has the effect that the nacelle relative to the prevailing wind direction has a malposition of often several degrees, which have a negative impact on the efficiency of the wind turbine, but also on the burden can.

There is therefore a need, in a rotor blade, but also in a tower of a wind turbine, a rotor blade of a tidal power plant and other hollow bodies and other components, a distortion or deformation of the relevant component, ie a movement of a first point to a second point, which may be arranged, for example, in an interior of the hollow body to detect. By replacing the conventional sensors used on the domes of wind turbines and a direct measurement or detection of the deformation of the tower or the rotor blades so both damage can be avoided if necessary, as well as increased efficiency of the wind turbine. Here, the detection of deformation or distortion should be as reliable and easy.

Conventionally, the use of laser distance measuring methods is discussed here. For this purpose, the rotor blade in question is often measured from outside the wind turbine. However, the measurement accuracy of laser pitch measurement methods is often inadequate, especially for smaller, twisted changes in a distance value. In order to detect a sheet deformation along two linearly independent deformation directions, the use of a laser distance measuring method would require two different measuring systems.

Therefore, there is a need, at this juncture, to provide an apparatus for detecting a distance value that enables more efficient detection of one or more distance values along linearly independent directions. This need is met by a device for detecting a distance value of a first point from a second point according to claim 1 or a method for detecting a distance value of a first point from a second point according to claim 10.

An apparatus for detecting a distance value of a first point from a second point, wherein the first point and the second point are arranged on a component and are spaced from one another by the distance value perpendicular to an extension direction of the component, according to one embodiment comprises a carrier, which is mechanically fixedly connected to the first point, a transmission member which is mechanically fixedly connected to the second point and mechanically coupled to the carrier such that the transmission member upon movement of the second point relative to the first point perpendicular to the direction of extension on a force the carrier and a strain sensitive sensor mechanically connected to the carrier, wherein the carrier is adapted to respond to the force exerted by the transmission member with a deformation, and wherein the deformation-sensitive sensor is adapted to the deformation of the carrier capture. A method for detecting a distance value of a first point from a second point, wherein the first point and the second point are arranged on a component and spaced apart by the distance value perpendicular to an extension direction of the component, according to an embodiment comprises providing a carrier, which is mechanically fixedly connected to the first point, exerts a force on the carrier upon movement of the second point with respect to the first point perpendicular to the extension direction, so that the carrier reacts to the applied force with a deformation, and detecting the deformation of the carrier.

An embodiment of a device and a method for detecting a distance value of a first point from a second point is based on the finding that the fact that the carrier is mechanically fixedly connected to the first point and the transmission component is mechanically fixed to the second point, however, these two are connected to each other, a movement of the second point relative to the first point on the transmission member is transmitted to the carrier, whereupon this reacts with a deformation. This deformation can be detected with the aid of the deformation-sensitive sensor. Due to the mechanical coupling of the transmission member with the carrier, the carrier may not only react with deformation along one direction to the movement of the transmission member, but also deformation along a second direction linearly independent of the first direction when the second point accordingly moved along the second direction relative to the first point.

In the case of a component, in connection with a device according to an exemplary embodiment, it can be a hollow body, for example a rotor blade or a tower of a wind power plant. Likewise, the component or the hollow component may be a rotor blade of a tidal power plant. However, it can also be a solid material component. In a device according to an embodiment, the first point and the second point may be spaced apart along the spanwise direction. In this case, the carrier may extend substantially along the extension direction of the component. In such a case, the carrier and the transmission member may be formed such that upon movement of the second point substantially perpendicular to the extending direction, deformation of the carrier exceeds deformation of the transmission member by more than a predetermined factor, the predetermined factor being at least 1, for example , at least 2, at least 5, at least 10, at least 50, at least 100 or at least 1000 may be. As a result, the movement of the second point with respect to the first point can be transmitted to the carrier substantially, but at least to a not inconsiderable proportion, so that at least this portion can be detected or detected by the deformation-sensitive sensor mechanically connected to the carrier.

This can be done, for example, by a suitable choice of the geometry and / or the choice of material of the transmission component and the carrier, a spring constant of these components with respect to a (deformation) direction the aforementioned ratios to each other. The spring constant of the transmission component may in this case be, for example, from a distance of the first point to the point of mechanical coupling of the transmission component and the carrier in the case of the carrier and in the case of Depend on a transmission component from a distance of the aforementioned coupling point to the second point.

Thus, in one exemplary embodiment, the carrier and / or the transmission component may comprise, for example, a steel such as a stainless steel, titanium, a carbon fiber or a glass fiber reinforced plastic or another material.

A device according to an embodiment may further comprise an evaluation circuit coupled to the strain sensitive sensor and configured such that a sensor signal provided by the strain sensitive sensor that includes information regarding the deformation of the carrier is received therefrom and an evaluation signal Basis of the detected sensor signal can be provided, which includes information relating to the distance value. In this way, further processing or utilization of the signal supplied by the device can optionally be simplified, since the evaluation signal can be adjusted in comparison to the sensor signal, for example with regard to its signal strength, signal impedance, value range or other parameters. Likewise, if necessary, nonlinearities and other defects can be corrected. For this purpose, the evaluation circuit can comprise, for example, a memory in which characteristic fields and / or parameters or coefficients are stored, which can be used for correction or signal adaptation in the context of mathematical methods and equations.

In one exemplary embodiment of a device, the transmission component can essentially enclose a right angle with the carrier in a deformation-free state. Thereby, the transmission member can be aligned, for example, along an expected deformation direction, so that deformation of the transmission member can be further reduced as compared with the deformation of the beam.

In a device according to an embodiment, the transmission member may comprise a hinge with a housing and a pivotable about at least two axes component. This may make it possible to reduce deformations and / or distortions in the event of a movement of the second point to the first point in the transmission member. In other embodiments, the pivotable component may optionally be pivotable about three linearly independent axes. Thus, in such a device according to an embodiment, the joint may be a ball joint and the pivotable component comprise an at least partially spherical member. As a result, not only possibly occurring deformations of the transmission component can be intercepted along two linearly independent deformation directions, but optionally also an assembly can be simplified as a ball joint often constitutes a joint which can enable pivoting about three linearly independent axes. Regardless of the exact configuration of the joint, in such a device according to one embodiment, the housing may comprise a self-lubricating sliding shell. As a result, any tendency to stick-slip occurring in a mechanical system may possibly be reduced. Thus, in such an embodiment, the housing and / or the sliding shell made of a plastic, for example polytetrafluoroethylene (PTFE) be made or comprise the plastic. In the case of a ball joint, the sliding shell can for example have an at least partially spherical sliding surface.

Regardless of the exact configuration of such a joint, in such a device, according to one embodiment, the housing may be mechanically coupled to the second point and the pivotable component may be connected to the carrier. Likewise, in order to facilitate the assembly, the housing may be designed in several parts, for example in two parts. Regardless of the precise nature of such a joint, in such a device according to an embodiment, the transmission member may comprise a mounting member which is mechanically connected to the housing of the transmission member. By providing such a mounting component, it may be possible to adapt the device more precisely to the geometric conditions of the component. If necessary, assembly and / or maintainability of the device can also be improved in that the assembly component can remain connected to the component, while the housing of the joint can be exchanged if necessary. In such a device according to an embodiment, the transmission member and the mounting member may be connectable such that an overall height of the mounting member and housing is adaptable. In this way, it may be possible to adapt the device more precisely to the geometric conditions of the component by, for example, attaching the mounting component or the transmission component to the component at different points. As a result, if necessary, an identical device can be used in connection with different components.

For this purpose, the housing and the mounting member may be mechanically connected to each other, for example, via a thread, which is adjustable by a counterpoint during assembly with respect to the overall height.

In a device according to an exemplary embodiment, the transmission component may comprise a connecting component, which is mechanically connected to the carrier in such a way that only linear movements along the carrier can be compensated. This may make it possible to reduce, possibly even avoid, deformations that occur when, for example, the carrier or the component changes along the direction of extent due to thermal or other effects in their extent. As a result, a measurement accuracy of the deformation-sensitive sensor can be increased if necessary.

In such a device according to one embodiment, a sealing element or a scraper, which is designed in such a way as to prevent the penetration of contaminants into the carrier or into the connecting component, can be arranged between the carrier and the connecting component. In this way, if appropriate, a tendency to seizure or other mechanical impairment of the linear displaceability of the two components to each other can be reduced. As a result, a higher measuring accuracy of a device according to an exemplary embodiment can optionally be made possible over a longer period of time. In such a device according to one embodiment, the carrier can be configured, for example, as a hollow profile. The hollow profile of the carrier can in this case change along the extension direction, for example. Thus, the hollow profile can be made, for example, in the region of the deformation-sensitive sensor square or polygonal, in order to attach the deformation-sensitive sensor to the carrier. lighter, while the hollow profile in the region of the connecting member is designed round or rotationally symmetrical, to allow rotation of the connecting member to the carrier. In addition, a material thickness of the carrier along the direction of extension can also be varied in order to increase deformation of the carrier, for example in the region of the deformation-sensitive sensor. For example, the

Hollow section of the carrier in the region of the deformation-sensitive sensor have a lower material thickness than in another area. Thus, in the region of the deformation-sensitive sensor, the hollow profile can have a material thickness which is lower by one material thickness factor than in the other region, wherein the material thickness factor can be, for example, at least 1.5, at least two, at least 2.5, or at least three.

In a device according to an embodiment, the strain-sensitive sensor may comprise two sensor elements connected or coupled to the carrier along a deformation direction. As a result, if appropriate, a measurement accuracy can be improved by the use of a plurality of appropriately interconnected and / or evaluated sensor elements.

A device according to an exemplary embodiment may further comprise a further deformation-sensitive sensor, which is mechanically connected to the carrier, wherein the further deformation-sensitive sensor is designed and arranged such that it detects a deformation along a further deformation direction that is dependent on a deformation direction, which makes the deformation-sensitive sensor detectable, is different. This makes it possible, with the aid of only one carrier and only one transmission component, but by the use of at least two deformation-sensitive sensors, namely the deformation-sensitive sensor and the further deformation-sensitive sensor, to detect two linearly independent deformation directions.

For this purpose, in such a device according to an embodiment of the further deformation-sensitive sensor relative to the deformation-sensitive sensor with respect to the extension direction of the component by an angle, for example 30 °, for example 60 ° or 90 °, for example, offset from the carrier. For example, if the carrier in the region of the deformation-sensitive sensor as angular or designed polygonal hollow profile, this can be done to make the device easier and possibly easier calibration of the device.

An embodiment of a rotor blade of a wind turbine comprises a receptacle for mounting on a rotor of the wind turbine and a device according to an embodiment as described above. The rotor blade is in this case the component, wherein the first and the second point are located on an inner surface or an outer surface of the rotor blade. The first point is arranged closer than the second point on the receptacle for mounting on the rotor. Likewise, an embodiment includes a tower of a wind turbine, in which the tower is the component and the first and the second point lie on an inner surface or an outer surface of the tower, or a rotor wing of a tidal power plant, which may be similar to that of the wind turbine.

In one embodiment of a method for detecting a distance value of a first point from a second value, the component may be a rotor blade of a wind turbine. Likewise, the first and second points may be disposed on an inner surface or an outer surface of the rotor blade. The distance value can in this case make it possible to infer a bending or deformation of the rotor blade. Thus, if appropriate, a difference of the detected distance value from a nominal value can characterize the deformation of the rotor blade or of another component. Accordingly, in one embodiment of a method for detecting a distance value of a first point and a second point, the component may also be a tower of a wind turbine, wherein the first and second points are disposed on an inner surface or an outer surface of the tower. An exemplary embodiment therefore also includes a rotor blade of a wind turbine, which comprises a receptacle for mounting on a rotor of the wind turbine and a device according to an embodiment, wherein the rotor blade is the component, wherein the first and the second point on an inner surface or an outer surface of the rotor blade, and wherein the first point is located closer than the second point to the receptacle for mounting on the rotor.

In other embodiments, a hollow component in the sense of the present description, such a component of a wind turbine or other system be hollow and at the same time substantially elongated along the direction of extension and extending in a straight line. As this definition shows, the hollow components or hollow bodies, in particular the rotor blades and the tower and corresponding sections of these components.

A frictional connection is achieved by friction, a cohesive connection by molecular or atomic interactions and forces and a positive connection by geometric connection of the respective connection partners.

Embodiments are described below with reference to the accompanying figures and explained.

Fig. 1 shows a perspective view of a rotor blade for illustrating possible blade deformations; and FIG. 2 shows a schematic cross-sectional representation through a device according to an exemplary embodiment.

In the context of the present description, summary reference numbers for objects, structures, and other components will be used when describing the component in question itself or more corresponding components within one embodiment or within several embodiments. Passages of the description which refer to one component are therefore also transferable to other components in other embodiments, unless this is explicitly excluded or if this results from the context. If individual components are designated, individual reference symbols are used, which are based on the corresponding summarizing reference symbols. In the following description of embodiments, therefore, the same reference numerals designate the same or similar components. Components which occur multiple times in one exemplary embodiment or in different exemplary embodiments may in this case be embodied identically and / or differently with respect to some of their technical parameters or implemented. It is thus possible, for example, that several components within an embodiment may be identical with respect to one parameter, but different with respect to another parameter.

1 shows a perspective view of a section of a rotor blade 100 of a wind turbine. The rotor blade 100 has a receptacle 120 for mounting the rotor blade 100 on the rotor of the wind turbine on a proximal end 110 facing a rotor of the wind power plant. The receptacle 120 has a mounting surface 140 aligned substantially perpendicular to an extension direction 130 of the rotor blade 100 and having a plurality of bores 150 for screwing to the rotor. Alternatively or additionally, bolts or studs can be used, which can be laminated or glued. As a result, damage to a laminar structure of the rotor blade 100 may possibly be avoided.

The rotor blade 100, which is also referred to simply as a "blade", is an example of a component 160 that may be used in embodiments thereof Other components 160 include, for example, a tower of a wind turbine, a rotor blade of a tidal power plant, a fuselage of an aircraft 1 shows a schematic diagram of a profile of the rotor blade 100 over a plurality of dash-dotted contour lines, thus the rotor blade 100 has an edge region 170 and a surface region 180. The rotor blade 100 is here after assembly The rotor (not shown in FIG. 1) can be rotated or swiveled with regard to the angle of attack substantially around the direction of extent 130 of the rotor blade 100 or of the component 160. As a result, the edge region 170 and the surface region 180 can be adapted to the prevailing wind conditions over a wide range and according to the rule de flow to be aligned.

As already described, not inconsiderable forces act on the rotor blade 100 in this case. These can lead to a sheet deformation 190, as shown in Fig. 1 by two curved arrows. Here, a sheet deformation 190-1, which is substantially perpendicular to the surface area 180, referred to as a flapwise, a sheet deformation 190-2, which is substantially perpendicular to the edge portion 170, referred to as edge-like (edgewise) , As will be explained in more detail below in connection with FIG. 2, online determination of the rotor blade loads on a wind turbine may be advisable on the one hand for determining the rotor blade loads occurring on the rotor blade 100, but also for aligning the wind turbine with the prevailing wind currents. These can be used for active system control, for example, by adjusting the angle of attack of the rotor blade 100 or else the orientation of the nacelle on the tower. As a result, a better wind field tracking of the wind turbine as well as a better blade load limitation in turbulence is possible. In addition, the actual rotor loads can be determined from the measured blade loads.

2 shows a schematically simplified cross-sectional view through a device 200 according to an exemplary embodiment for detecting a distance value of a first point 210 from a second point 220. The first point 210 and the second point 220 are arranged on an inner surface of a component 160 in which it is rotor blade 100. The first point 210 and the second point 220 are in this case perpendicular to the extension direction 130 spaced apart by the distance value. In other exemplary embodiments, the device 200 may also be arranged on an outer surface of the component 160, so that there also the first and / or the second point 210, 220 lie or are arranged.

The apparatus 200 further includes a carrier 230 mechanically fixed to the first point 210. For this purpose, the device 200 has a fastening component 240, which is adhesively connected to the component 160 or the rotor blade 100 via an adhesive bond 250. The carrier 230 is in this case connected via a screw 260 with the fastening component 240. For this purpose, the fastening component 240 corresponding threaded holes and optionally aligned openings through which the screws of the screw 260 can be tightened. Accordingly, the carrier 230 has corresponding openings, via which it can be screwed to the fastening component 240. About the screw 260 so the carrier 230 is firmly clamped to the mounting member 240 and thus to the component 160 and the rotor blade 100. Of course, in other exemplary embodiments, other techniques for mechanical connection of the carrier 230 can be used with the fastening member 240. Likewise, if appropriate, the fastening component 240 can be connected to the rotor blade 100 or the component 160 using a different fastening technique. For example, the fastening component 240 can also be screwed to the component 160. In addition, in exemplary embodiments, if appropriate, the fastening component 240 can be completely removed and the carrier 230 can be connected directly to the component 160 or the rotor blade 100. The use of a fastening component 240 and the bond 250, however, makes it possible to mount the carrier 230 in the rotor blade 100 in a comparatively easy manner. For example, a rotor blade is often made of a laminated material comprising glass fiber or carbon fiber reinforced plastics. In this, the introduction of threaded holes can be problematic, which is why a bond 250 of the Befestigungsbau- part 240 with the rotor blade 100 is an interesting option for maintenance purposes.

In order to facilitate the orientation of the carrier 230 and to facilitate the attachment of the carrier 230 to the fastening component 240, this can be carried out in the region of the fastening component 240, for example as a hollow profile with an angular or polygonal cross section. For example, the support 230 in this area may be square or rectangular.

The carrier 230 extends in this embodiment substantially along the extension direction 130 of the component 160.

The apparatus 200 further includes a transmission member 270 mechanically fixed to the second point 220. The transmission member 270 is further mechanically coupled to the carrier 230 such that the transmission member 270 exerts a force on the carrier 230 upon movement of the second point 220 opposite the first point 210 perpendicular to the extension direction 130. For this purpose, the transmission component 270 has a joint 280 with a housing 290 and a component 300 which can be pivoted about at least two axes. The joint 280 is in this case more precisely designed as a ball joint, the pivotable component 300 at least in sections is designed spherical. To facilitate the assembly of the joint 280 this is often in several parts, so for example designed in two parts, to allow for easier assembly of the pivotable member 300. The housing 290 in this case comprises a self-lubricating sliding shell 310, which is designed so that an inclination of the pivotable member 300 is reduced for static friction. As a result, an inclination for stick-slip can be reduced if necessary during a pivoting of the pivotable component 300. The sliding shell 310 may in this case be made, for example, from a plastic, for example polyethylene tetrafluoroethylene (PTFE). For example, polytetrafluoroethylene has identical coefficients of adhesion and sliding friction, so that the onset of a jerk slip can be significantly reduced. The pivotable member 300 may be made of a metallic material such as an alloy or a steel. In principle, however, the pivotable component 300 can also be made of a plastic.

Due to the at least sectionally spherical configured pivotable component 300, the sliding shell 310 likewise has a corresponding, at least sectionally, spherical sliding surface. The sliding shell 310 may moreover, similar to the housing 290, for better installation and maintainability in several parts, so for example in two parts, be executed. The hinge 280 also has two circumferential sealing elements 320-1 and 320-2 which protect the Gleitfiäche the sliding cup 310 and the corresponding counter surface of the pivotable member 300 from contamination. In this way, if appropriate, the service life of the device 200 or the service life of the device 200 can be extended. Optionally, the sealing elements 320 may even allow the use of a device 200 in a dirtier environment.

In this case, the pivotable component 300 is mechanically connected to the carrier 230 via a connecting component 330, while the housing 290 is mechanically coupled (indirectly) to the second point 220. Thus, the transmission component 270 has a mounting component 340 which is mechanically connected to the housing 290 of the transmission component 270 is. The connection of these two components is in this case designed via a thread 350, so that the mounting member 340 and the housing 290 of the joint 280 are connectable so that an overall height of the mounting member 340 and housing 290 are adjustable. As a result, the transmission component 270 can be adapted to different distances perpendicular to the extension direction 130 in an unstressed state of the component 160. The total height of mounting member 340 and housing 290 can be fixed via a counter. Of course, other embodiments of the adjustability of the overall height of mounting member 340 and housing 290 may be implemented in other embodiments. These include, for example, frictional connections, for example deadlocks. Likewise, a cohesive connection can be created, so for example, a bond or a weld. These connection techniques can also be used in addition or as an alternative to countering the thread 350. The assembly component 340 can in this case be connected to the component 160 or the rotor blade 100 in a different manner. Thus, as also shown in FIG. 2, the mounting component 340 may be connected, for example via an adhesive bond 360, to the rotor blade 100 in the region of the second point 220. Alternatively or additionally, the mounting component 340 may also be mechanically connected directly to the component 160 via a screw connection 370. A screw 370, as indicated in Fig. 2, but may be less interesting, especially in rotor blades 100 due to the problem described above.

The connecting component 330, which mechanically connects the pivotable component 300 to the carrier 230, is configured in such a way that the connecting component 330 only compensates for linear movements along the carrier. In other words, the connection component 330 is connected to the carrier 230 such that only linear movements along the carrier 230 can be compensated. The connecting part 330 is therefore guided linearly displaceable in the carrier 230.

In order to prevent, or at least minimize, contamination from impurities in the region between support 230 and connection part 330, a sealing element 380 or a wiper is implemented and provided between the support 230 and the connection part 330, which is provided in the event of a linear movement between connects Training part 330 and support 230 adhering to the connecting part 330 contaminants, so for example, solid or liquid particles, abstreift. A corresponding scraper or a corresponding sealing element 380 can thus be designed, for example, as a membrane.

In order to allow penetration of the connecting part 330 into the carrier 230, the carrier 230 is designed as a hollow profile. In this case, in order to enable rotations about the extension direction of the carrier 230, the connecting part 330 is often rotationally symmetrical, that is to say round, for example. Correspondingly, the support 230 can also be configured to be round or rotationally symmetrical, at least in this area. In contrast to this, the support 230 can, as already mentioned above, be designed, for example, in the region of the fastening component 240 in an angular or polygonal manner.

The apparatus 200 further includes a strain sensitive sensor 390 mechanically coupled to the carrier 230 and configured to detect deformation of the carrier 230. The carrier 230 is in this case designed such that it reacts to a force exerted by the transmission member with a corresponding deformation. For this purpose, the hollow profile of the carrier 230, for example in the region of the deformation-sensitive sensor 390, may have a lower material thickness than is the case at another point or in another region of the carrier 230. Thus, the material thickness of the hollow profile of the carrier 230 in the region of the deformation-sensitive sensor 390 may differ from the material thickness at the corresponding other point or region by a material thickness factor which is at least 1.5, at least 2, at least 2.5 or at least 3 and indicates How much the corresponding material in the region of the deformation-sensitive sensor 390 of the carrier 230 is thinner.

Thus, by virtue of its geometrical design, the choice of material and other parameters, the carrier 230 can be designed, for example, such that, responsive to a force along a direction 400, the carrier 230 reacts with a deformation that is greater by a predetermined factor than a corresponding deformation of the transmission component 270. This predetermined factor should be at least 1, but may be significantly greater, in particular due to the free design of the components in question. Thus, in other embodiments, the predetermined factor may also have values greater than 10, greater than 100, or greater than 1000. Due to the geometric configuration of the carrier 230 and the fact that the deformation-sensitive sensor 390 is applied to this, the carrier 230 is also referred to as a sensor-carrier Pro fil. Since the transfer member transmits the movement along the directions 400 of the rotor blade 100, it is also referred to as a "sheet movement transformer".

The directions 400-1 and 400-2 drawn in FIG. 2 correspond to the directions of movement of the second point 220 to the first point perpendicular to the extension direction 130 of the component 160 or the rotor blade 100 and the corresponding force directions associated with this movement. In other words, the directions 400-1 and 400-2 shown in FIG. 2 coincide with the sheet deformation directions 190-1 and 190-2. The direction 400-1 thus again describes the sheet-by-sheet deformation, while the direction 400-2 designates the edge-wise direction.

If a deformation of the hollow body 160 occurs due to an external influence on the rotor blade 100 or for another reason, so that the second point 220 moves to the first point along one of the directions 400, the backlash-free joint formed by the joint 280 is deflected. Connection exerted a force on the carrier 230 so that it deforms in the manner described. This deformation can be detected via the deformation-sensitive sensor or sensors 390.

As corresponding bending stress sensors strain gauges, piezoelectric sensors or optical sensors, such as fiber Bragg gratings can be used. In the strain gauges due to the mechanical stress of the same to an extension and / or a taper of resistive strips, which lead to an increase in the corresponding electrical resistance, which can then be detected by a corresponding evaluation circuit. In the case of piezoelectric sensors, due to the mechanical stress, the formation of a voltage which can likewise be detected by a corresponding evaluation circuit occurs. In the case of fiber Bragg gratings, the deformation of the carrier and thus the deformation of the deformation-sensitive sensor 390 changes a lattice constant of the corresponding lattice, which can be detected by a (selective) frequency shift of a radiation which is refracted or reflected at the lattice. This measurement method is based on that at predetermined angular ratios, a broadband radiation spectrum is radiated into the grating. Likewise, if appropriate, a monochromatic irradiation can be used. In order to amplify a sensor signal of the deformation-sensitive sensor 390, the deformation-sensitive sensor may comprise two sensor elements located opposite one another along a deformation direction, that is, for example, the direction 400-1. Thus, the embodiment of a device 200 shown in FIG. 2 comprises two sensor elements 410-1 and 410-2, which together form the deformation-sensitive sensor 390. The two sensor elements 410 can be combined with one another on the basis of their interconnection or on the basis of an evaluation or processing of their individual sensor signals in the evaluation circuit not shown in FIG. 2 in such a way that overall a larger signal amplitude is available so that, if necessary a more accurate detection of the deformation is possible.

Thus, an apparatus 200 according to an embodiment may further include an evaluation circuit, not shown in FIG. 2, coupled to the strain sensitive sensor 390 and configured to receive a sensor signal provided thereby and to provide an evaluation signal based on the sensed sensor signal. The sensor signal of the deformation-sensitive sensor 390 in this case comprises information relating to the deformation of the carrier, while the evaluation signal provided by the evaluation circuit comprises information relating to the distance value. Such an evaluation circuit may comprise, for example, an analog and / or a digital component. Thus, the signal processing, for example, analog, as well as digitally done. For example, if the strain-sensitive sensor 390 has a highly non-linear characteristic, it may be advisable to convert it into a corresponding linearized output signal, which may then be the evaluation signal, for example. Such an implementation can for example be based on a mathematical relationship or on the basis of a characteristic curve or a characteristic field. Depending on which technique is used, the evaluation circuit can have such a memory, which includes the necessary parameters, coefficients, characteristics or characteristic fields. In order to effect the least possible deformation of the transmission component 270 during a movement of the transmission component 270 along one of the directions 400, in particular along the direction 400-1, in which the transmission component also extends with its overall height, it may be advisable in embodiments at least in a deformation-free state, the transmission member 270 and the carrier 230 to be arranged such that they enclose substantially a right angle with each other. Of course, in other embodiments, a different geometry may be used. As already mentioned at the beginning, not only a deformation of the rotor blade 100 or of the component 160 along the direction 400-1 may be detected with the aid of a device 200, but optionally also along a further direction of deformation or direction, which is aligned with the direction 400-4. 1 includes a finite angle, that is different from this. For this purpose, the exemplary embodiment of a device 200 illustrated in FIG. 2 has a further deformation-sensitive sensor 420, which is likewise mechanically connected to the carrier 230. The further deformation-sensitive sensor 420 is in this case designed and arranged such that it can detect a deformation along a further deformation direction, namely the direction 400-2. This is different from the direction of deformation corresponding to the direction 400-1 and to which the strain sensitive sensor 390 responds. The further deformation-sensitive sensor 420 is arranged offset relative to the extension direction 130 of the component 160 by an angle on the carrier 230.

Similar to the deformation-sensitive sensor 390, the further deformation-sensitive sensor 420 also has two sensor elements 430 mounted on opposite sides of the carrier 230, of which only one can be seen in FIG. The further deformation-sensitive sensor 420 can in this case work on the basis of the same technology as the deformation-sensitive sensor 390. Of course, however, it is also possible to use different measuring concepts, which may be advisable if, for reasons of cost and / or accuracy, 400 different requirement profiles are provided to the device 200 with regard to the detection of the corresponding distance values along the different directions. FIG. 2 thus shows a device 200 which can be used as a bending stress sensor unit for blade-load detection. The blade springing is transmitted in this via the play ball joint 280 to a bending profile, namely the carrier 230 also referred to as a sensor carrier profile. At a base point of the bending profile (carrier 230), the bending stress can then be measured, for example, in two planes, for example parallel to the surface of the rotor blade 100 and parallel to the edge of the rotor blade 100. The bending stress generated by the deformation-sensitive sensor (s) 390, 420 can be used directly as a control variable for tracking the wind turbine. The use of a metallic carrier 230 allows the use of strain gauge sensors, which are often difficult to realize on glass fiber reinforced plastics. The device 200, as shown in FIG. 2, due to the implementation of the two deformation-sensitive sensors 390, 420, enables a parallel and / or simultaneous detection of the edged and flapwise blade deformations.

One exemplary embodiment thus also includes a rotor blade 100 of a wind power plant with a receptacle for mounting on a rotor of the wind power plant, which device comprises a device 200 according to one exemplary embodiment. The rotor blade 100 in this case represents the component 160, wherein the first and the second point 210, 220 lie on an inner surface or an outer surface of the rotor blade 100. The first point 210 is in this case arranged closer than the second point 220 on the receptacle for mounting on the rotor blade.

However, in addition to use in the context of a rotor blade of a wind power plant, embodiments can also be used with other components 160. For example, a device 100 can also be used for tower monitoring of a wind power plant. Accordingly, an embodiment also includes a tower of a wind turbine with a device according to an embodiment, wherein the tower represents the component 160. In principle, however, corresponding devices according to an exemplary embodiment can also be used for completely different components 160, even if previously substantially embodiments have been described in connection with wind power plants. In principle, exemplary embodiments can also be used in the context of tidal power plants (eg rotor blades), pipes, aircraft, ship caves and other systems. be used. Optionally, it may be advisable to isolate the device 200 from a medium arranged or flowing on or in the corresponding component 160, in order to avoid inadvertent influencing of the device 200.

An embodiment of a method for detecting a distance value of a first point 210 from a second point 220 thus comprises providing a carrier 230 mechanically connected to the first point 210. The first point 210 and the second point 220 are in turn arranged on an inner surface or an outer surface of a component 160 and perpendicular to an extension direction 130 of the component 160 spaced apart by the distance value. Such a method further includes applying a force to the carrier 230 upon movement of the second point 220 relative to the first point 210 perpendicular to the extension direction 130 such that the carrier responds to the applied force with deformation. The method further comprises detecting the deformation of the carrier 230, which can be done, for example, via a corresponding deformation-sensitive sensor 390 or 420.

Although some aspects have been described in the context of a device, it will be understood that these aspects also constitute a description of the corresponding method, so that a block or a component of a device is also to be understood as a corresponding method step or as a feature of a method step , Similarly, aspects described in connection with or as a method step also represent a description of a corresponding block or detail or feature of a corresponding device.

Depending on particular implementation requirements, embodiments of the invention may be implemented in hardware or in software. The implementation may be performed using a digital storage medium, such as a floppy disk, a DVD, a Blue-Ray Disc, a CD, a ROM, a PROM, an EPROM, an EEPROM or a FLASH memory, a hard disk or a hard disk other magnetic or optical memory are stored on the electronically readable control signals, which can cooperate with a programmable hardware component or cooperate such that the respective method is performed. A programmable hardware component may be provided by a processor, a central processing unit (CPU), a graphics processing unit (GPU), a computer, a computer system, an application-specific integrated circuit (ASIC), an integrated circuit (IC), a system on chip (SOC) system, a programmable logic element or a field programmable gate array with a microprocessor (FPGA = Field Programmable Gate Array). The digital storage medium may therefore be machine or computer readable. Thus, some embodiments include a data carrier having electronically readable control signals capable of interacting with a programmable computer system or programmable hardware component such that one of the methods described herein is performed. One embodiment is thus a data carrier (or a digital storage medium or a computer readable medium) on which the program is recorded for performing any of the methods described herein.

In general, embodiments of the present invention may be implemented as a program, firmware, computer program, or computer program product having program code or data, the program code or data operative to perform one of the methods when the program resides on a processor or a computer programmable hardware component expires. The program code or the data can also be stored, for example, on a machine-readable carrier or data carrier. The program code or the data may be present, inter alia, as source code, machine code or bytecode as well as other intermediate code.

A further embodiment is further a data stream, a signal sequence or a sequence of signals which represents the program for carrying out one of the methods described herein. The data stream, the signal sequence or the sequence of signals can be configured, for example, to be transferred via a data communication connection, for example via the Internet or another network. Exemplary embodiments are also data representing signaling sequences suitable for transmission over a network or data communication link, the data representing the program.

For example, a program according to one embodiment may implement one of the methods during its execution by, for example, reading out or writing into it one or more data, thereby optionally switching operations or other operations in transistor structures, amplifier structures, or other electrical, optical, magnetic or operating according to another operating principle components are caused. Accordingly, by reading a memory location, data, values, sensor values or other information can be detected, determined or measured by a program. A program can therefore acquire, determine or measure quantities, values, measured variables and other information by reading from one or more storage locations, as well as effect, initiate or execute an action by writing to one or more storage locations and control other devices, machines and components ,

Thus, an embodiment also includes a program having a program code for performing a method according to an embodiment, when the program runs on a programmable hardware component.

The embodiments described above are merely illustrative of the principles of the present invention. It will be understood that modifications and variations of the arrangements and details described herein will be apparent to others of ordinary skill in the art. Therefore, it is intended that the invention be limited only by the scope of the appended claims, rather than by the specific details presented in the description and explanation of the embodiments herein.

Claims

P atentanspr che device and method for detecting a distance value

A device (200) for detecting a distance value of a first point (210) from a second point (220), wherein the first point (210) and the second point (220) are arranged on a component (160) and perpendicular to one Extension direction (130) of the component (160) are spaced apart by the distance value, with the following features: a carrier (230) which is mechanically fixedly connected to the first point (210); a transmission member (270) mechanically fixed to the second point (220) and mechanically coupled to the support (230) such that the transmission member (270) moves against the first point (210) when the second point (220) moves ) exerts a force on the carrier (230) perpendicular to the extension direction (130); and a strain sensitive sensor (390) mechanically coupled to the carrier (230), the carrier (230) being configured to respond to the force applied by the transmission member (270) with a deformation; wherein the strain sensitive sensor (390) is configured to detect the deformation of the carrier (230); and wherein the transmission component (270) comprises a connection component (330) which is mechanically connected to the support (230) such that only linear movements along the support (230) can be compensated.

The apparatus (200) of claim 1, further comprising an evaluation circuit coupled to the strain sensitive sensor (390) and configured to receive a sensor signal provided by the strain sensitive sensor (390) that includes information regarding the deformation of the beam (390). 230), and to provide an evaluation signal based on the detected sensor signal including information regarding the distance value.

A device (200) as claimed in any one of the preceding claims, wherein the transfer member (270) includes substantially perpendicular to the support (230) in a non-deformed condition.

4. Device (200) according to one of the preceding claims, wherein the transmission member (270) has a hinge (280) with a housing (290) and a pivotable about at least two axes component (300).

The apparatus (200) of claim 4, wherein the housing (290) comprises a self-lubricating slip bowl (310).

6. Device (200) according to one of the preceding claims, wherein between the carrier (230) and the connecting member (330), a sealing element (380) or a scraper is arranged, which is designed to prevent ingress of contaminants in the carrier (230) or in the connecting member (330) to prevent.

7. Device (200) according to one of the preceding claims, in which the deformation-sensitive sensor (390) has two, along along a deformation direction (190, 400) opposite positions on the support (230) sensor elements (410).

8. Device (200) according to one of the preceding claims, further comprising a further deformation-sensitive sensor (390), which is mechanically connected to the carrier (230). The further deformation-sensitive sensor (390) is designed and arranged in such a way that it makes detectable deformation along a further deformation direction (190, 400) which is determined by a deformation direction (190, 400) of the deformation-sensitive sensor (390 ) makes detectable, is different.

A rotor blade (100) of a wind turbine having a receptacle (120) for mounting on a rotor of the wind turbine, comprising: a device (200) according to one of the preceding claims, wherein the rotor blade (100) is the component (160), wherein the first (210) and second points (220) lie against an inner surface or outer surface of the rotor blade (100), and wherein the first point (210) is closer than the second point (220) to the receptacle (120) for mounting is arranged on the rotor.

10. A method for detecting a distance value of a first point from a second point, wherein the first point and the second point are arranged on a component and perpendicular to an extension direction ) of the component (160) are spaced apart by the distance value, comprising:

Providing a carrier (230) mechanically fixed to the first point (210);

Applying a force to the carrier (230) upon movement of the second point (220) opposite the first point (210) perpendicular to the extension direction (210) by a transmission member (270) such that the carrier (230) is responsive to the applied force a deformation responds, wherein by connecting member (330) of the transmission member (270) only linear movements along the support (230) are compensated; and

Detecting the deformation of the carrier (230).