WO2005071382A1 - Device including a system adapted for use in temperature compensation of strain measurements in fibre-reinforced structures - Google Patents

Device including a system adapted for use in temperature compensation of strain measurements in fibre-reinforced structures Download PDF

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Publication number
WO2005071382A1
WO2005071382A1 PCT/DK2005/000031 DK2005000031W WO2005071382A1 WO 2005071382 A1 WO2005071382 A1 WO 2005071382A1 DK 2005000031 W DK2005000031 W DK 2005000031W WO 2005071382 A1 WO2005071382 A1 WO 2005071382A1
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WO
WIPO (PCT)
Prior art keywords
optical fibre
holding means
connecting means
fibre
holding
Prior art date
Application number
PCT/DK2005/000031
Other languages
French (fr)
Inventor
Ivan Engmark Mortensen
Tage Svendsen
Andrew Munro Gallon
Original Assignee
Lm Glasfiber A/S
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Lm Glasfiber A/S filed Critical Lm Glasfiber A/S
Priority to PL05700581T priority Critical patent/PL1709416T3/en
Priority to DK05700581.1T priority patent/DK1709416T3/en
Priority to US10/586,547 priority patent/US7813598B2/en
Priority to CN2005800029403A priority patent/CN1910436B/en
Priority to EP05700581.1A priority patent/EP1709416B1/en
Priority to ES05700581.1T priority patent/ES2672789T3/en
Publication of WO2005071382A1 publication Critical patent/WO2005071382A1/en

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Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
    • G01L1/00—Measuring force or stress, in general
    • G01L1/26—Auxiliary measures taken, or devices used, in connection with the measurement of force, e.g. for preventing influence of transverse components of force, for preventing overload
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F03—MACHINES OR ENGINES FOR LIQUIDS; WIND, SPRING, OR WEIGHT MOTORS; PRODUCING MECHANICAL POWER OR A REACTIVE PROPULSIVE THRUST, NOT OTHERWISE PROVIDED FOR
    • F03D—WIND MOTORS
    • F03D80/00—Details, components or accessories not provided for in groups F03D1/00 - F03D17/00
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F03—MACHINES OR ENGINES FOR LIQUIDS; WIND, SPRING, OR WEIGHT MOTORS; PRODUCING MECHANICAL POWER OR A REACTIVE PROPULSIVE THRUST, NOT OTHERWISE PROVIDED FOR
    • F03D—WIND MOTORS
    • F03D80/00—Details, components or accessories not provided for in groups F03D1/00 - F03D17/00
    • F03D80/80—Arrangement of components within nacelles or towers
    • F03D80/82—Arrangement of components within nacelles or towers of electrical components
    • F03D80/85—Cabling
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
    • G01L1/00—Measuring force or stress, in general
    • G01L1/24—Measuring force or stress, in general by measuring variations of optical properties of material when it is stressed, e.g. by photoelastic stress analysis using infrared, visible light, ultraviolet
    • G01L1/242—Measuring force or stress, in general by measuring variations of optical properties of material when it is stressed, e.g. by photoelastic stress analysis using infrared, visible light, ultraviolet the material being an optical fibre
    • G01L1/246—Measuring force or stress, in general by measuring variations of optical properties of material when it is stressed, e.g. by photoelastic stress analysis using infrared, visible light, ultraviolet the material being an optical fibre using integrated gratings, e.g. Bragg gratings
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
    • G01M11/00—Testing of optical apparatus; Testing structures by optical methods not otherwise provided for
    • G01M11/08—Testing mechanical properties
    • G01M11/083—Testing mechanical properties by using an optical fiber in contact with the device under test [DUT]
    • G01M11/086—Details about the embedment of the optical fiber within the DUT
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E10/00—Energy generation through renewable energy sources
    • Y02E10/70—Wind energy
    • Y02E10/72—Wind turbines with rotation axis in wind direction
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
    • Y02P70/50—Manufacturing or production processes characterised by the final manufactured product

Definitions

  • Device including a system adapted for use in temperature compensation of strain measurements in fibre-reinforced structures
  • the present invention relates to a device comprising a fibre-reinforced part and including at least one system adapted for use in temperature compensation of strain measurements, said system comprising at least one optical fibre as well as connecting means adapted for connection of light emitting means and light receiving means to the optical fibre, said optical fibre comprising a number of reflecting structures.
  • the invention further relates to a method of manufacturing a device as well as to connecting means and holding means.
  • strain gauges are commonly denominated "strain gauges" and are provided on structures to measure actual strain in the structure. In case the strain gauge is subject to a change in temperature, this will affect the measurement due to natural elongation or contraction. To have an accurate measurement it is therefore necessary to compensate the strain measurement with respect to change of temperature.
  • Various methods have been used to provide compensation for temperature change, but none suitable for fibre-reinforced parts.
  • One object of the invention is to provide means suitable for use in providing compensation for temperature change in strain measurement, which may be built into a fibre-reinforced part of a device. Another object is to provide a method of manufacturing such a device where said means are built into a fibre-reinforced part.
  • the system comprises at least one holding means adapted to hold one or more loops formed on the optical fibre, in a way where at least one loop may substan- tially freely change length when subject to a change in temperature, and where the at least one optical fibre is at least extending between the connecting means and the holding means, and where said at least one loop, which may substantially freely change length, is held by the holding means and comprises a part of the optical fibre, which comprises a number of re- fleeting structures, and where said optical fibre, the connecting means and the holding means are at least partly embedded in said fibre-reinforced part of said device.
  • the holding means are adapted to hold one or more loops formed on the optical fibre, in a way where at least one loop may substantially freely change length when subject to a change in temperature, and that the loops are held by the holding means with said at least one loop comprising a part of the optical fibre, which comprises a number of reflecting structures, it is obtained that the at least one loop may be used to obtain a passive refer- ence measurement, which is independent of any strain present in the part, whereby said reference measurement may be used for providing compensation for temperature change in an active strain measurement performed on said part.
  • the connecting means and the holding means may be placed independently, with the only limitation being the length of the optical fibre, which may be chosen freely.
  • This may be used to place the holding means near an active strain gauge placed on the part, whereby the temperature of the strain gauge and the loop on the optical fibre comprising the number of reflecting structures may be substantially identical, and hence very accurate temperature compensation may be obtained for a strain measurement performed by that particular strain gauge.
  • the connecting means may be placed freely, it may be placed at any convenient position suitable for connecting light emitting and light receiving means.
  • Such free placing is of significant advantage by large and/or elongated parts, such as blades for wind turbines, which have lengths longer than 30 meters and widths of more than 3 meters, and where strain gauges may be employed at any position.
  • the connecting means and the holding means are the fibre-reinforced part of said device, and the items are well protected and safely kept in place. It is also obtained that the temperature of the optical fibre and the fibre-reinforced part are at least nearly identical.
  • the system may comprise one connecting means adapted for connection of light emitting means and one connecting means adapted for connection of light receiving means to the optical fibre, where the optical fibre extends from one of the connection means to another via at least one holding means.
  • This provides two connections to the optical fibre, which e.g. leave a spare connection in case the optical fibre should break on one side of the holding means, which will disable connection to and from one of the connection means to the at least one loop, which may freely change length.
  • a preferred embodiment may involve that the system comprises two or more holding means, where each holding means comprises at least one loop comprising a part of the optical fibre, which comprises a number of reflecting structures. It is hereby obtained that accurate temperature compensation may be performed for two or more strain measurements performed with strain gauges placed in different places on fibre-reinforced the part. This is advantageous especially for large parts where it may be desired to monitor strain in more than one location.
  • Another preferred embodiment may involve that an optical fibre enters the holding means in one direction and exits in another direction.
  • the holding means may in this way be used for changing direction of the path in which the optical fibre is led, e.g. towards another holding means or connecting means. Free positioning of the holding means and the connecting means is thereby enhanced.
  • a method for manufacturing a device comprising a fibre-reinforced part including a system adapted for use in temperature compensation of strain measurements, said system comprising at least one optical fibre as well as connecting means adapted for connection of light emitting means and light receiving means to the optical fibre, said optical fibre comprising a number of reflecting structures, where the system com- prises at least one holding means adapted to hold one or more loops formed on the optical fibre, in a way where at least one loop may substantially freely change length when subject to a change in temperature, and where moulding means according to a predetermined shape of said device are provided as well as fibres for reinforcement and resin, where the method comprises independent steps of:
  • the optical fibre into one or more loops and holding said loops with the holding means, in a way where at least one loop is substantially free to change length when subject to a change in temperature, said at least one loop comprising a part of the optical fibre, which comprises a number of reflecting structures, - applying the fibres for reinforcement, the optical fibre, the connecting means, the holding means and the resin on the moulding means and forming the device in a way where the optical fibre, the connecting means and the holding means are at least partly embedded in at least the resin.
  • a device may be manufactured, where said device in- volves corresponding functions and technical effects as the aforementioned device according to the invention.
  • the method steps are independent, since the optical fibre may e.g. be connected to the connecting means and/or holding means before or after the connecting and/holding means are applied on the moulding means.
  • the fibres for reinforcement may preferably be applied in a dry state along with the optical fibre, the connecting means and the holding means, where after the resin is infused in a state where air is evacuated, such as in a VARTM process (Vacuum Assisted Resin Transfer Moulding).
  • the method may preferably be performed in a way where the optical fibre is connected with the connecting means, and where a part of the optical fibre is formed into a number of loops, and holding said loops with the holding means, in a way where at least one loop is substantially free to change length when subject to a change in temperature, said at least one loop comprising a part of the optical fibre, which comprises a number of reflecting structures, and where the optical fibre is winded onto at least one spool before the optical fibre, the connecting means and the holding means are applied.
  • the optical fibre which is fragile, may hereby stay protected on the spool during storage and handling until it is actually used.
  • the optical fibre may be applied from the spool and continuously fastened to the fibres for reinforcement while being unwinded.
  • the optical fibre thus stays protected at all time.
  • the system comprises at least one holding means adapted to hold one or more loops formed on the optical fibre, in a way where at least one loop may substantially freely change length when subject to a change in temperature,
  • said at least one loop which may substantially freely change length, is held by the holding means and comprises a part of the optical fibre, which comprises a number of reflecting structures.
  • Such a system is hereby suitable for use in a device and a method according to the invention, whereby functions and technical effects earlier mentioned may be obtained.
  • a preferred embodiment of the system involves that the system is assembled to form a ready-for-use kit, said kit comprising at least one spool onto which the optical fibre is winded.
  • a kit is easy to handle and employ under normal manufacturing conditions for fibre-reinforced parts, where fibres and resin are used, and hence personnel has to wear personal protection equip- ment such as heavy gloves etc.
  • Fig. 1 shows one side of a device according to the invention
  • Fig. 2 shows one side of another device
  • Fig. 3 shows an elevated view of connecting means
  • Fig. 4 shows an elevated view of holding means
  • Fig. 5 shows a holding means seen from above
  • Fig. 6 shows another holding means seen from above
  • Fig. 7 shows one side of an alternative embodiment of a device
  • Fig. 8 shows a configuration of more devices for use in a wind turbine
  • Fig. 9 shows another configuration of more devices for use in a wind turbine
  • Fig. 1 displays a device 1 comprising a fibre-reinforced part 2, where the device 1 in this example is a blade 11 for a wind turbine. Near the root of the blade 11 two connecting means 5 are placed, whereto an optical fibre 4 is connected. Between the connecting means 5 the optical fibre 4 is placed in three individual holding means 6, each holding one or more loops 7 formed on the fibre 4, said loops 7 including at least one loop, which may freely change length when subject to a change in temperature, and which includes a number of reflecting structures, such as Bragg gratings.
  • Fig. 2 displays a device 1 corresponding to Fig. 1 , however having connecting means 5 being integrated in a common housing 18.
  • Fig. 3 displays a particular embodiment of connecting means 5 including a housing 13, which has a general shape as a truncated pyramid.
  • An optical fibre 4 which is supported by a string 10, is via a tapered, elongate and resilient portion 12 lead into a depression in the housing 13 and laid in a loop, which is fixated with resilient glue 20, and finally ending in a free loop having a plug 19 connected.
  • the plug 19 is intended for connection to undisplayed light emitting and/or light receiving means.
  • a wall 21 may be placed on the housing, or it may be machined or cast when the housing 13 is made.
  • the housing 13 will in use be covered by e.g.
  • the connecting means 5 may the be placed on a moulding means with the undisplayed plate facing said moulding means, where after reinforcement fibres are placed around the connecting means 5 and resin introduced. After curing of the device, the plate will be facing a surface of the device and the connecting means 5 be accessed from an internal side by removing the plate.
  • Fig. 4 displays holding means 6 comprising a housing 14 provided with a recess 15 including a circular path 16, which is connected to recesses 17.
  • the circular path 16 is adapted to hold one or more loops 7 formed on an optical fibre 4, where at least one loop comprises a number of reflecting structures, such as Bragg gratings.
  • the fibre 4 is fixed in the recesses 17 with resilient glue and enters and exits, respectively, the housing 14 via resilient portions 22.
  • the fibre 4 may be supported by a string 10, e.g. made from woven or braided glass fibres.
  • the loops 7 lay loose and have a slightly smaller diameter than the circular path 16, and may hence slide substantially without resistance, and are hence free to change length when subject to a change in temperature.
  • the housing 14 may be closed with an undisplayed plate in a similar way as explained above with regard to the connecting means 5, and the holding means 6 may be placed in a similar way during manufacture to obtain internal access.
  • Both the housings 13 and 14 may preferably be made from a polymeric material by processes involving casting, milling or the like.
  • Fig. 5 and 6 display a housing 14 comprising a recess 15 having a circular path 16 and two connecting recesses 17. As shown, the recesses 17 may be adapted to extend in different directions, whereby an undisplayed optical fibre placed in loops in the circular path 16 and exiting via the recesses 17 may be led in different directions.
  • Fig. 6 it is shown that the recesses 15, 17 and the circular path 16 may be placed in a depression 25, where they may be covered by an undisplayed plate and fixed with screws placed in holes 24. A fibre may enter and exit via holes 26.
  • Fig. 7 displays a device 1 comprising a fibre-reinforced part 2, where the device 1 in this example is a blade 11 for a wind turbine.
  • one connecting means 5 is placed, whereto an optical fibre 4 is connected.
  • the optical fibre 4 is extending to holding means 6, and is here placed in three individual holding means 6, each holding one or more loops 7 formed on the fibre 4, said loops 7 including at least one loop, which may freely change length when subject to a change in temperature, and which includes a number of reflecting structures.
  • the fibre 4 ends in a free end 27.
  • Fig. 8 and 9 each display a device 1 comprising three fibre-reinforced parts, which here are three blades 11 for a wind turbine.
  • Optical fibres 4 are each led in a path in the blades 11.
  • the optical fibres 4 are in Fig. 8 connected from blade to blade via connection means 5.
  • the optical fibres 4 extend via non-displayed holding means 6, each holding one or more non-displayed loops 7 formed on the fibre 4, said loops 7 including at least one loop, which may freely change length when subject to a change in temperature, and which includes a number of reflecting structures.
  • one fibre 4 ends in an end 27, which is not connected to connection means, whereas in Fig. 9 all three fibres 4 end in non-connected ends 27.
  • light emitting and light receiving means 26 are provided, by which light is emitted into the fibres 4, and some light is reflected by the reflecting structures, and is then received by the means 26.
  • the connecting means 5 comprise an elongate resilient portion 12, which portion is adapted to support an optical fibre 3 when connected to the connecting means.
  • the housing 13 of the connecting means 5 and/or the housing 14 of the holding means 6 may be provided with a shape, which is substantially frusto- conical or substantially like a truncated pyramid.
  • the housings 13, 14 of the connecting means 5 and the holding means 6 may be made from a polymeric material, whereby said means as well as the optical fibre 4 are made essentially without using any e.g. metallic parts to maintain a generally low risk of a lightning strike in said means, although the connecting means 5 may include metallic plugs 19 for connecting the optical fibre 4 to means for emitting and receiving light, respectively.

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Abstract

The present invention relates to a device comprising a fibre-reinforced part and including at least one system comprising at least one optical fibre as well as connecting means adapted for connection of light emitting means and light receiving means to the optical fibre, said optical fibre comprising a number of reflecting structures. One object of the invention is to provide means suitable for use in providing compensation for temperature change in strain measurement, which may be built into fibre-reinforced parts of a device. This is obtained by having holding means adapted to hold one or more loops formed on the optical fibre, in a way where at least one loop may substantially freely change length when subject to a change in temperature.

Description

Device including a system adapted for use in temperature compensation of strain measurements in fibre-reinforced structures
The present invention relates to a device comprising a fibre-reinforced part and including at least one system adapted for use in temperature compensation of strain measurements, said system comprising at least one optical fibre as well as connecting means adapted for connection of light emitting means and light receiving means to the optical fibre, said optical fibre comprising a number of reflecting structures. The invention further relates to a method of manufacturing a device as well as to connecting means and holding means.
Different types of devices for use when measuring strain in structural elements are known, e.g. foils provided with a metallic layer forming a prede- termined path adapted for electrical measurement and optical fibres provided with Bragg gratings for optical measurement. The latter being a strain sensor comprising an optical waveguide having a plurality of reflecting structures, so-called Bragg gratings, along its length. Such devices are commonly denominated "strain gauges" and are provided on structures to measure actual strain in the structure. In case the strain gauge is subject to a change in temperature, this will affect the measurement due to natural elongation or contraction. To have an accurate measurement it is therefore necessary to compensate the strain measurement with respect to change of temperature. Various methods have been used to provide compensation for temperature change, but none suitable for fibre-reinforced parts.
One object of the invention is to provide means suitable for use in providing compensation for temperature change in strain measurement, which may be built into a fibre-reinforced part of a device. Another object is to provide a method of manufacturing such a device where said means are built into a fibre-reinforced part.
Further objects appear from the description elsewhere. New features of a device according to the invention involve that the system comprises at least one holding means adapted to hold one or more loops formed on the optical fibre, in a way where at least one loop may substan- tially freely change length when subject to a change in temperature, and where the at least one optical fibre is at least extending between the connecting means and the holding means, and where said at least one loop, which may substantially freely change length, is held by the holding means and comprises a part of the optical fibre, which comprises a number of re- fleeting structures, and where said optical fibre, the connecting means and the holding means are at least partly embedded in said fibre-reinforced part of said device.
When the holding means are adapted to hold one or more loops formed on the optical fibre, in a way where at least one loop may substantially freely change length when subject to a change in temperature, and that the loops are held by the holding means with said at least one loop comprising a part of the optical fibre, which comprises a number of reflecting structures, it is obtained that the at least one loop may be used to obtain a passive refer- ence measurement, which is independent of any strain present in the part, whereby said reference measurement may be used for providing compensation for temperature change in an active strain measurement performed on said part. By the at least one optical fibre at least extending between the connecting means and the holding means, and the at least one loop, which may substantially freely change length, being held by the holding means and comprising a part of the optical fibre, which comprises a number of reflecting structures, it is obtained that the connecting means and the holding means may be placed independently, with the only limitation being the length of the optical fibre, which may be chosen freely. This may be used to place the holding means near an active strain gauge placed on the part, whereby the temperature of the strain gauge and the loop on the optical fibre comprising the number of reflecting structures may be substantially identical, and hence very accurate temperature compensation may be obtained for a strain measurement performed by that particular strain gauge. Since also the connecting means may be placed freely, it may be placed at any convenient position suitable for connecting light emitting and light receiving means. Such free placing is of significant advantage by large and/or elongated parts, such as blades for wind turbines, which have lengths longer than 30 meters and widths of more than 3 meters, and where strain gauges may be employed at any position. By at least partly embedding the optical fibre, the connecting means and the holding means are the fibre-reinforced part of said device, and the items are well protected and safely kept in place. It is also obtained that the temperature of the optical fibre and the fibre-reinforced part are at least nearly identical.
In one advantageous embodiment the system may comprise one connecting means adapted for connection of light emitting means and one connecting means adapted for connection of light receiving means to the optical fibre, where the optical fibre extends from one of the connection means to another via at least one holding means. This provides two connections to the optical fibre, which e.g. leave a spare connection in case the optical fibre should break on one side of the holding means, which will disable connection to and from one of the connection means to the at least one loop, which may freely change length.
A preferred embodiment may involve that the system comprises two or more holding means, where each holding means comprises at least one loop comprising a part of the optical fibre, which comprises a number of reflecting structures. It is hereby obtained that accurate temperature compensation may be performed for two or more strain measurements performed with strain gauges placed in different places on fibre-reinforced the part. This is advantageous especially for large parts where it may be desired to monitor strain in more than one location.
Another preferred embodiment may involve that an optical fibre enters the holding means in one direction and exits in another direction. The holding means may in this way be used for changing direction of the path in which the optical fibre is led, e.g. towards another holding means or connecting means. Free positioning of the holding means and the connecting means is thereby enhanced.
Other features of a device according to the invention are the subject of claims 4 - 12.
Other features of the invention involve a method for manufacturing a device comprising a fibre-reinforced part including a system adapted for use in temperature compensation of strain measurements, said system comprising at least one optical fibre as well as connecting means adapted for connection of light emitting means and light receiving means to the optical fibre, said optical fibre comprising a number of reflecting structures, where the system com- prises at least one holding means adapted to hold one or more loops formed on the optical fibre, in a way where at least one loop may substantially freely change length when subject to a change in temperature, and where moulding means according to a predetermined shape of said device are provided as well as fibres for reinforcement and resin, where the method comprises independent steps of:
- connecting the optical fibre with the connecting means,
- forming part of the optical fibre into one or more loops and holding said loops with the holding means, in a way where at least one loop is substantially free to change length when subject to a change in temperature, said at least one loop comprising a part of the optical fibre, which comprises a number of reflecting structures, - applying the fibres for reinforcement, the optical fibre, the connecting means, the holding means and the resin on the moulding means and forming the device in a way where the optical fibre, the connecting means and the holding means are at least partly embedded in at least the resin.
By such a method a device may be manufactured, where said device in- volves corresponding functions and technical effects as the aforementioned device according to the invention. The method steps are independent, since the optical fibre may e.g. be connected to the connecting means and/or holding means before or after the connecting and/holding means are applied on the moulding means. The fibres for reinforcement may preferably be applied in a dry state along with the optical fibre, the connecting means and the holding means, where after the resin is infused in a state where air is evacuated, such as in a VARTM process (Vacuum Assisted Resin Transfer Moulding).
The method may preferably be performed in a way where the optical fibre is connected with the connecting means, and where a part of the optical fibre is formed into a number of loops, and holding said loops with the holding means, in a way where at least one loop is substantially free to change length when subject to a change in temperature, said at least one loop comprising a part of the optical fibre, which comprises a number of reflecting structures, and where the optical fibre is winded onto at least one spool before the optical fibre, the connecting means and the holding means are applied. The optical fibre, which is fragile, may hereby stay protected on the spool during storage and handling until it is actually used.
According to another preferred feature, the optical fibre may be applied from the spool and continuously fastened to the fibres for reinforcement while being unwinded. The optical fibre thus stays protected at all time.
Further features of the invention involve a system adapted for a device or a method according to any of claims 1-15, said system being adapted for use in temperature compensation of strain measurements and comprising at least one optical fibre as well as connecting means adapted for connection of light emitting means and light receiving means to the optical fibre, said optical fibre comprising a number of reflecting structures, wherein:
- the system comprises at least one holding means adapted to hold one or more loops formed on the optical fibre, in a way where at least one loop may substantially freely change length when subject to a change in temperature,
- and where the at least one optical fibre is at least extending between the connecting means and the holding means,
- and where said at least one loop, which may substantially freely change length, is held by the holding means and comprises a part of the optical fibre, which comprises a number of reflecting structures.
Such a system is hereby suitable for use in a device and a method according to the invention, whereby functions and technical effects earlier mentioned may be obtained.
A preferred embodiment of the system involves that the system is assembled to form a ready-for-use kit, said kit comprising at least one spool onto which the optical fibre is winded. Such a kit is easy to handle and employ under normal manufacturing conditions for fibre-reinforced parts, where fibres and resin are used, and hence personnel has to wear personal protection equip- ment such as heavy gloves etc.
Preferred features of connecting means and holding means according to the invention are the subject of claims 18-23.
In the following the invention is described with reference to the drawings, which display examples of embodiments of the invention.
Fig. 1 shows one side of a device according to the invention, Fig. 2 shows one side of another device,
Fig. 3 shows an elevated view of connecting means,
Fig. 4 shows an elevated view of holding means,
Fig. 5 shows a holding means seen from above, and
Fig. 6 shows another holding means seen from above
Fig. 7 shows one side of an alternative embodiment of a device
Fig. 8 shows a configuration of more devices for use in a wind turbine
Fig. 9 shows another configuration of more devices for use in a wind turbine
Fig. 1 displays a device 1 comprising a fibre-reinforced part 2, where the device 1 in this example is a blade 11 for a wind turbine. Near the root of the blade 11 two connecting means 5 are placed, whereto an optical fibre 4 is connected. Between the connecting means 5 the optical fibre 4 is placed in three individual holding means 6, each holding one or more loops 7 formed on the fibre 4, said loops 7 including at least one loop, which may freely change length when subject to a change in temperature, and which includes a number of reflecting structures, such as Bragg gratings.
Fig. 2 displays a device 1 corresponding to Fig. 1 , however having connecting means 5 being integrated in a common housing 18.
Fig. 3 displays a particular embodiment of connecting means 5 including a housing 13, which has a general shape as a truncated pyramid. An optical fibre 4, which is supported by a string 10, is via a tapered, elongate and resilient portion 12 lead into a depression in the housing 13 and laid in a loop, which is fixated with resilient glue 20, and finally ending in a free loop having a plug 19 connected. The plug 19 is intended for connection to undisplayed light emitting and/or light receiving means. To ease forming of a loop on the fibre 4 and holding this in place while the glue 20 is curing, a wall 21 may be placed on the housing, or it may be machined or cast when the housing 13 is made. The housing 13 will in use be covered by e.g. a plate, preferably resting on an undisplayed seal to form a tight connection. When manufacturing a device, the connecting means 5 may the be placed on a moulding means with the undisplayed plate facing said moulding means, where after reinforcement fibres are placed around the connecting means 5 and resin introduced. After curing of the device, the plate will be facing a surface of the device and the connecting means 5 be accessed from an internal side by removing the plate.
Fig. 4 displays holding means 6 comprising a housing 14 provided with a recess 15 including a circular path 16, which is connected to recesses 17. The circular path 16 is adapted to hold one or more loops 7 formed on an optical fibre 4, where at least one loop comprises a number of reflecting structures, such as Bragg gratings. The fibre 4 is fixed in the recesses 17 with resilient glue and enters and exits, respectively, the housing 14 via resilient portions 22. The fibre 4 may be supported by a string 10, e.g. made from woven or braided glass fibres. The loops 7 lay loose and have a slightly smaller diameter than the circular path 16, and may hence slide substantially without resistance, and are hence free to change length when subject to a change in temperature. The housing 14 may be closed with an undisplayed plate in a similar way as explained above with regard to the connecting means 5, and the holding means 6 may be placed in a similar way during manufacture to obtain internal access. Both the housings 13 and 14 may preferably be made from a polymeric material by processes involving casting, milling or the like.
Fig. 5 and 6 display a housing 14 comprising a recess 15 having a circular path 16 and two connecting recesses 17. As shown, the recesses 17 may be adapted to extend in different directions, whereby an undisplayed optical fibre placed in loops in the circular path 16 and exiting via the recesses 17 may be led in different directions. In Fig. 6 it is shown that the recesses 15, 17 and the circular path 16 may be placed in a depression 25, where they may be covered by an undisplayed plate and fixed with screws placed in holes 24. A fibre may enter and exit via holes 26. Fig. 7 displays a device 1 comprising a fibre-reinforced part 2, where the device 1 in this example is a blade 11 for a wind turbine. Near the root of the blade 11 one connecting means 5 is placed, whereto an optical fibre 4 is connected. From the connecting means 5 the optical fibre 4 is extending to holding means 6, and is here placed in three individual holding means 6, each holding one or more loops 7 formed on the fibre 4, said loops 7 including at least one loop, which may freely change length when subject to a change in temperature, and which includes a number of reflecting structures. At the farthest holding means 6 the fibre 4 ends in a free end 27.
Fig. 8 and 9 each display a device 1 comprising three fibre-reinforced parts, which here are three blades 11 for a wind turbine. Optical fibres 4 are each led in a path in the blades 11. The optical fibres 4 are in Fig. 8 connected from blade to blade via connection means 5. The optical fibres 4 extend via non-displayed holding means 6, each holding one or more non-displayed loops 7 formed on the fibre 4, said loops 7 including at least one loop, which may freely change length when subject to a change in temperature, and which includes a number of reflecting structures. In Fig. 8 one fibre 4 ends in an end 27, which is not connected to connection means, whereas in Fig. 9 all three fibres 4 end in non-connected ends 27. In Fig. 8 and 9 light emitting and light receiving means 26 are provided, by which light is emitted into the fibres 4, and some light is reflected by the reflecting structures, and is then received by the means 26.
As depicted in Fig. 3, the connecting means 5 comprise an elongate resilient portion 12, which portion is adapted to support an optical fibre 3 when connected to the connecting means.
The housing 13 of the connecting means 5 and/or the housing 14 of the holding means 6 may be provided with a shape, which is substantially frusto- conical or substantially like a truncated pyramid. The housings 13, 14 of the connecting means 5 and the holding means 6 may be made from a polymeric material, whereby said means as well as the optical fibre 4 are made essentially without using any e.g. metallic parts to maintain a generally low risk of a lightning strike in said means, although the connecting means 5 may include metallic plugs 19 for connecting the optical fibre 4 to means for emitting and receiving light, respectively.
It is to be understood that the invention as disclosed in the description and in the figures may be modified and changed and still be within the scope of the invention as claimed hereinafter.

Claims

Claims
1. A device comprising a fibre-reinforced part and including at least one system adapted for use in temperature compensation of strain measurements,
5 said system comprising at least one optical fibre as well as connecting means adapted for connection of light emitting means and light receiving means to the optical fibre, said optical fibre comprising a number of reflecting structures, wherein o - the system comprises at least one holding means adapted to hold one or more loops formed on the optical fibre, in a way where at least one loop may substantially freely change length when subject to a change in temperature, 5 - and where the at least one optical fibre is at least extending between the connecting means and the holding means,
- and where said at least one loop, which may substantially freely change length, is held by the holding means and comprises a part of 0 the optical fibre, which comprises a number of reflecting structures,
- and where said optical fibre, the connecting means and the holding means are at least partly embedded in said fibre-reinforced part of said device.5
2. A device according to claim 1 , where the system comprises one connecting means adapted for connection of light emitting means and one connecting means adapted for connection of light receiving means to the optical fibre, and where the optical fibre extends from one of the connection means to o another via at least one holding means.
3. A device according to claim 1 or 2, where the system comprises two or more holding means, and where each holding means comprises at least one loop comprising a part of the optical fibre, which comprises a number of reflecting structures.
4. A device according to one or more of claims 1-3, where the optical fibre enters the holding means in one direction and exits in another direction.
5. A device according to one or more of claims 2-4, where two connecting means are integrated in a common housing.
6. A device according to one or more of claims 1-5, where the connecting means are placed by a surface of said part and adapted to be accessible from an internal position within said part.
7. A device according to one or more of claims 1-6, where the optical fibre at least between the connecting means and the holding means is provided with support means for reinforcement of the fibre.
8. A device according to claim 7, where the support means include a string comprising woven or braided fibres, preferably glass fibres.
9. A device according to claim 8, where the optical fibre is fastened to the string with double coated tape.
10. A device according to claim 8, where the optical fibre is integrated in the string, preferably by weaving or sowing.
11. A device according to one or more of claims 1-10, where the connecting means and the holding means each comprise a recess, in which a part of the optical fibre is fastened with glue.
12. A device according to one or more of claims 1-11 , where said part is a fibre-reinforced blade shell of a blade for a wind turbine.
13. A method for manufacturing a device comprising a fibre-reinforced part including a system adapted for use in temperature compensation of strain measurements, said system comprising at least one optical fibre as well as connecting means adapted for connection of light emitting means and light receiving means to the optical fibre, said optical fibre comprising a number of reflecting structures, where the system comprises at least one holding means adapted to hold one or more loops formed on the optical fibre, in a way where at least one loop may substantially freely change length when subject to a change in temperature, and where moulding means according to a predetermined shape of said device are provided as well as fibres for reinforcement and resin, where the method comprises independent steps of:
- connecting the optical fibre with the connecting means, - forming at least one part of the optical fibre into one or more loops and holding said loops with the holding means, in a way where at least one loop is substantially free to change length when subject to a change in temperature, said at least one loop comprising a part of the optical fibre, which comprises a number of reflecting structures,
- applying the fibres for reinforcement, the optical fibre, the connecting means, the holding means and the resin on the moulding means and forming the device in a way where the optical fibre, the connecting means and the holding means are at least partly embedded in at least the resin.
14. A method according to claim 13, where the optical fibre is connected with the connecting means, and where a part of the optical fibre is formed into one or more loops, and holding said one or more loops with the holding means in a way where at least one loop is substantially free to change length when subject to a change in temperature, said at least one loop comprising a part of the optical fibre, which comprises a number of reflecting structures, and where the optical fibre is winded onto at least one spool before the opti- cal fibre, the connecting means and the holding means are applied on the moulding means.
15. A method according to claim 14, where the optical fibre is applied from the spool and continuously fastened to the fibres for reinforcement while being unwinded.
16. A system adapted for a device or a method according to any of the preceding claims, said system being adapted for use in temperature compensa- tion of strain measurements and comprising at least one optical fibre as well as connecting means adapted for connection of light emitting means and light receiving means to the optical fibre, said optical fibre comprising a number of reflecting structures, wherein - the system comprises at least one holding means adapted to hold one or more loops formed on the optical fibre, in a way where at least one loop may substantially freely change length when subject to a change in temperature, - and where the at least one optical fibre is at least extending between the connecting means and the holding means,
- and where said at least one loop, which may substantially freely change length, is held by the holding means and comprises a part of the optical fibre, which comprises a number of reflecting structures.
17. A system according to claim 16, where said system is assembled to form a ready-for-use kit, said kit comprising at least one spool onto which the optical fibre is winded.
18. Connecting means adapted for a device, method or system according to any of the preceding claims, where the connecting means are adapted for connecting light emitting means and/or light receiving means to an optical fibre, said connecting means comprising a housing adapted for storing and holding an end section of an optical fibre being formed with at least one loop placed by said end section.
19. Connecting means according to claim 18, where the connecting means comprise an elongate resilient portion, which portion is adapted to support an optical fibre when connected to the connecting means.
20. Connecting means according to claim 18 or 19, where the housing is pro- vided with a shape, which is substantially frusto-conical or substantially like a truncated pyramid.
21. Holding means adapted for a device, method or system according to any of the preceding claims 1- 17, where the holding means comprise a housing provided with at least one recess, said recess having at least one substantially circular path adapted for substantially surrounding loops formed on an optical fibre.
22. Holding means according to claim 21 , where the substantially circular section is connected with at least two recesses.
23. Holding means according to claim 21 or 22, where the housing is provided with a shape, which is substantially frusto-conical or substantially like a truncated pyramid.
PCT/DK2005/000031 2004-01-23 2005-01-20 Device including a system adapted for use in temperature compensation of strain measurements in fibre-reinforced structures WO2005071382A1 (en)

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PL05700581T PL1709416T3 (en) 2004-01-23 2005-01-20 Device including a system adapted for use in temperature compensation of strain measurements in fibre-reinforced structures
DK05700581.1T DK1709416T3 (en) 2004-01-23 2005-01-20 Device comprising a system adapted for use in temperature compensation for load measurements in fiber-reinforced structures
US10/586,547 US7813598B2 (en) 2004-01-23 2005-01-20 Device including a system adapted for use in temperature compensation of strain measurements in fibre-reinforced structures
CN2005800029403A CN1910436B (en) 2004-01-23 2005-01-20 Device including a system adapted for use in temperature compensation of strain measurements in fibre-reinforced structures
EP05700581.1A EP1709416B1 (en) 2004-01-23 2005-01-20 Device including a system adapted for use in temperature compensation of strain measurements in fibre-reinforced structures
ES05700581.1T ES2672789T3 (en) 2004-01-23 2005-01-20 Device that includes a system adapted for use in temperature compensation of tension measurements of fiber reinforced structures

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DKPA200400093 2004-01-23
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PCT/DK2005/000046 WO2005071383A1 (en) 2004-01-23 2005-01-24 A connector box partly embedded in a fibre-reinforced part for protecting and connecting purposes

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Cited By (24)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1780523A1 (en) * 2005-10-31 2007-05-02 General Electric Company Wind turbine systems, monitoring systems and processes for monitoring stress in a wind turbine blade
GB2440953A (en) * 2006-08-18 2008-02-20 Insensys Ltd Monitoring wind turbine blades
GB2440955A (en) * 2006-08-18 2008-02-20 Insensys Ltd Wind turbine blade monitoring
GB2440954A (en) * 2006-08-18 2008-02-20 Insensys Ltd Optical monitoring of wind turbine blades
WO2008101496A2 (en) * 2007-02-19 2008-08-28 Vestas Wind Systems A/S Wind turbine blade with strain sensing means, wind turbine, block sensor unit and uses hereof
DE102007015179A1 (en) * 2007-03-29 2008-10-02 Siemens Ag Pressure measuring device and method for determining wind power on wind turbines and use of the pressure measuring device and the method
WO2009052828A2 (en) * 2007-10-24 2009-04-30 Vestas Wind Systems A/S Wind turbine blade, wind turbine and method for manufacturing a wind turbine blade
GB2454253A (en) * 2007-11-02 2009-05-06 Insensys Ltd Monitoring strain on a wind turbine blade
WO2009056892A1 (en) * 2007-11-02 2009-05-07 Insensys Limited Sensor array
WO2009143850A2 (en) * 2008-05-30 2009-12-03 Vestas Wind Systems A/S A wind turbine rotor, a wind turbine and use thereof
WO2009143848A2 (en) * 2008-05-30 2009-12-03 Vestas Wind System A/S A wind turbine rotor, a wind turbine and use thereof
GB2461532A (en) * 2008-07-01 2010-01-06 Vestas Wind Sys As Sensor system and method for detecting deformation in a wind turbine component
WO2010001255A2 (en) * 2008-07-03 2010-01-07 Vestas Wind Systems A/S Embedded fibre optic sensor for wind turbine components
WO2010032134A2 (en) * 2008-09-22 2010-03-25 Vestas Wind Systems A/S Wind turbine rotor blade comprising an edge-wise bending insensitive strain sensor system
US7780328B2 (en) 2006-07-14 2010-08-24 Bae Systems Plc Heat distribution in a distributed lighting apparatus
US7909575B2 (en) * 2007-06-25 2011-03-22 General Electric Company Power loss reduction in turbulent wind for a wind turbine using localized sensing and control
US8120759B2 (en) 2008-03-31 2012-02-21 Vestas Wind Systems A/S Optical transmission strain sensor for wind turbines
EP2388476A3 (en) * 2010-04-29 2012-04-18 General Electric Company Method for temperature calibration of blade strain gauges and wind turbine rotor blade containing strain gauges
WO2013140085A1 (en) * 2012-03-20 2013-09-26 Snecma Detection and tracking of damage or impact of a foreign object on an aircraft engine fan
US8712703B2 (en) 2008-12-16 2014-04-29 Vestas Wind Systems A/S Turbulence sensor and blade condition sensor system
US8733164B2 (en) 2010-02-04 2014-05-27 Vestas Wind Systems A/S Wind turbine optical wind sensor
US9014863B2 (en) 2009-08-06 2015-04-21 Vestas Wind Systems A/S Rotor blade control based on detecting turbulence
IT201900008883A1 (en) * 2019-06-13 2020-12-13 Freni Brembo Spa Method and system for detecting and measuring a braking force of a vehicle brake system, using photonic sensors incorporated in a brake caliper
US11242839B2 (en) 2019-05-21 2022-02-08 Nordex Energy Se & Co. Kg Semi-finished product for a cable guide system of a wind turbine component, wind turbine component, wind turbine rotor blade and methods

Families Citing this family (23)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2832719B1 (en) * 2001-11-29 2004-02-13 Oreal ADHESIVE SEQUENCE ETHYLENIC COPOLYMERS, COSMETIC COMPOSITIONS CONTAINING THEM, AND USE OF SUCH COPOLYMERS IN COSMETICS
DE102006035274B4 (en) * 2006-07-31 2008-07-03 Technische Universität Dresden Fiber composite component with a sensor and display unit
DK200700647A (en) * 2007-04-30 2008-05-10 Lm Glasfiber As Measurement of geometric parameters for a wind turbine blade
WO2009037271A1 (en) * 2007-09-17 2009-03-26 Schleifring Und Apparatebau Gmbh Fibre-optic sensor for measuring deformations on wind power installations
ES2353320B1 (en) * 2008-02-08 2012-01-25 Gamesa Innovation & Technology S.L. AIRBRUSH SHOVEL WITH A LIGHT BEAM ON YOUR POINT.
CN101298980A (en) * 2008-04-18 2008-11-05 中国地震局地壳应力研究所 Design method and manufacturing technique of high-sensitivity temperature self-compensation optical fiber grating strain sensor
EP2350715A4 (en) * 2008-09-10 2012-03-14 Lake Shore Cryotronics Inc Compact fiber optic sensors and method of making same
US9770862B2 (en) 2008-09-10 2017-09-26 Kyton, Llc Method of making adhesion between an optical waveguide structure and thermoplastic polymers
US20110019178A1 (en) * 2009-07-22 2011-01-27 Christos Vlatas Method for post processing fiber optic strain measurement data
US8346043B2 (en) * 2009-07-30 2013-01-01 Jds Uniphase Corporation Fiber tray
ES2387364B1 (en) * 2010-09-14 2013-07-29 Gamesa Innovation & Technology, S.L. ELECTRONIC MODULE AND METHOD USED FOR THE BEARING OF THE BLADE
US9868536B2 (en) * 2013-10-30 2018-01-16 Goodrich Corporation Electrical interconnects for ice protection systems
DE102014200954A1 (en) * 2014-01-21 2015-07-23 Bayerische Motoren Werke Aktiengesellschaft Detection of local mechanical loads
DE102014210949A1 (en) * 2014-06-06 2015-12-17 Wobben Properties Gmbh Wind energy plant with optical pressure sensors and method for operating a wind energy plant
US9500561B2 (en) * 2014-06-20 2016-11-22 Bell Helicopter Textron Inc. Embedding fiber optic cables in rotorcraft composites
US10034471B2 (en) 2015-06-18 2018-07-31 Frontier Wind, Llc. Wildlife deterrence system arranged in wind turbine blade
US10655606B2 (en) 2015-06-24 2020-05-19 Vestas Wind Systems A/S Blade load sensing system for a wind turbine
WO2016206691A1 (en) * 2015-06-24 2016-12-29 Vestas Wind Systems A/S Blade load sensing system for a wind turbine
JP5879453B1 (en) * 2015-08-27 2016-03-08 新日鉄住金エンジニアリング株式会社 Method of introducing initial tensile strain into cable and optical fiber
US10830214B2 (en) * 2017-03-22 2020-11-10 General Electric Company Method for securing a lightning receptor cable within a segmented rotor blade
US10705298B1 (en) * 2019-04-26 2020-07-07 Lockheed Martin Corporation Fiber optic protective box for core-stiffened composite structures
CN111307325B (en) * 2020-03-26 2021-03-09 中国船舶科学研究中心（中国船舶重工集团公司第七0二研究所） Temperature compensation device of fiber grating strain sensor made of reinforced fiber composite material
CN111731503B (en) * 2020-06-09 2022-05-03 南京航空航天大学 Connection method of transmission interface of embedded sensor for rotor blade and rotor blade

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5094527A (en) * 1990-05-14 1992-03-10 Lockheed Corporation Temperature compensated strain sensor for composite structures
US5196694A (en) * 1991-05-13 1993-03-23 The Babcock & Wilcox Company Temperature compensated self-referenced fiber optic microbend pressure transducer
WO1997015805A1 (en) * 1995-10-26 1997-05-01 Bicc Public Limited Company Strain gauge
US5649035A (en) * 1995-11-03 1997-07-15 Simula Inc. Fiber optic strain gauge patch
EP0892244A2 (en) * 1997-07-18 1999-01-20 C.R.F. Società Consortile per Azioni Check system for monitoring the strain status of high pressure bottles particularly methane gas bottles for motor-vehiles
US5887107A (en) * 1997-04-09 1999-03-23 Ciena Corporation Strain relieving fiber optic multiplexer package

Family Cites Families (27)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA1299389C (en) 1986-10-30 1992-04-28 John W. Berthold Microbend fiber optic strain gauge
US4976587A (en) * 1988-07-20 1990-12-11 Dwr Wind Technologies Inc. Composite wind turbine rotor blade and method for making same
JPH03111526A (en) * 1989-09-26 1991-05-13 Ube Ind Ltd Manufacture of fiber reinforced metal matrix composite
FR2689632B1 (en) 1992-04-02 1997-09-19 Thomson Csf FIBER OPTICAL STRESS DETECTOR.
US5553165A (en) 1993-01-11 1996-09-03 Canon, Inc. Parallel error diffusion method and apparatus
US5381055A (en) * 1993-07-29 1995-01-10 Motorola, Inc. CMOS driver using output feedback pre-drive
US5533165A (en) 1994-08-30 1996-07-02 Burris; Kelly K. Smart structure egress channel
FR2727203B1 (en) 1994-11-18 1996-12-13 Commissariat Energie Atomique DOSE ELECTRIC GUIDE ROSETTE-TYPE OPTICAL MICRO-SYSTEM FOR MEASURING A LONGITUDINAL CONSTRAIN IN A PLANE STRUCTURE
CN1178012A (en) * 1995-04-19 1998-04-01 株式会社小松制作所 Tension member for optical fibre cable, production of the tension member, and optical fibre cable using the tension member
GB9510886D0 (en) * 1995-05-30 1995-07-26 Amp Great Britain Wire cutting electrical connector having test probe access
NO307314B1 (en) 1997-12-05 2000-03-13 Optoplan As Device for registration of buoy load
DK173460B2 (en) * 1998-09-09 2004-08-30 Lm Glasfiber As Windmill wing with lightning conductor
GB9824756D0 (en) * 1998-11-11 1999-01-06 Europ Economic Community A strain sensor and strain sensing apparatus
CN2353704Y (en) * 1999-02-09 1999-12-15 李忠联 Connector for plastic disintegrator with wind-driven conveyer
DK173607B1 (en) * 1999-06-21 2001-04-30 Lm Glasfiber As Wind turbine blade with lightning de-icing system
DE19949386C2 (en) * 1999-10-13 2002-04-11 Electro Terminal Gmbh Device connection box with cutting technology
AU768212B2 (en) * 1999-11-03 2003-12-04 Vestas Wind Systems A/S Method of controlling the operation of a wind turbine and wind turbine for use in said method
JP3519333B2 (en) 2000-02-10 2004-04-12 エヌ・ティ・ティ・アドバンステクノロジ株式会社 Optical fiber sensor
US6615875B2 (en) * 2000-08-30 2003-09-09 Owens Corning Composites Sprl. Liner for reinforcing a pipe and method of making the same
CN1139797C (en) * 2001-01-11 2004-02-25 南京航空航天大学 Technology for braiding composite material in optical fibre sensor and method for testing its performance
US6547448B2 (en) * 2001-05-15 2003-04-15 The Boeing Company Embeddable fiber optic connector and associated method
CN1145049C (en) * 2001-07-25 2004-04-07 华为技术有限公司 Fiber grating with passive temperature compensation and its making process
US6800956B2 (en) * 2002-01-30 2004-10-05 Lexington Bartlett Wind power system
NO334515B1 (en) * 2002-03-13 2014-03-31 Light Structures As Fiber optic sensor package
DK175275B1 (en) * 2002-03-19 2004-08-02 Lm Glasfiber As Transition area in wind turbine blade
CA2426711C (en) * 2002-05-02 2009-11-17 General Electric Company Wind power plant, control arrangement for a wind power plant, and method for operating a wind power plant
CN2570733Y (en) * 2002-10-10 2003-09-03 张继昌 Optical fibre strain transducer

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5094527A (en) * 1990-05-14 1992-03-10 Lockheed Corporation Temperature compensated strain sensor for composite structures
US5196694A (en) * 1991-05-13 1993-03-23 The Babcock & Wilcox Company Temperature compensated self-referenced fiber optic microbend pressure transducer
WO1997015805A1 (en) * 1995-10-26 1997-05-01 Bicc Public Limited Company Strain gauge
US5649035A (en) * 1995-11-03 1997-07-15 Simula Inc. Fiber optic strain gauge patch
US5887107A (en) * 1997-04-09 1999-03-23 Ciena Corporation Strain relieving fiber optic multiplexer package
EP0892244A2 (en) * 1997-07-18 1999-01-20 C.R.F. Società Consortile per Azioni Check system for monitoring the strain status of high pressure bottles particularly methane gas bottles for motor-vehiles

Cited By (57)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7303373B2 (en) 2005-10-31 2007-12-04 General Electric Company Wind turbine systems, monitoring systems and processes for monitoring stress in a wind turbine blade
AU2006230719B2 (en) * 2005-10-31 2013-01-10 General Electric Renovables España, S.L. Wind turbine systems, monitoring systems and processes for monitoring stress in a wind turbine blade
CN1959370B (en) * 2005-10-31 2013-04-03 通用电气公司 Wind turbine systems, monitoring systems and processes for monitoring stress in a wind turbine blade
EP1780523A1 (en) * 2005-10-31 2007-05-02 General Electric Company Wind turbine systems, monitoring systems and processes for monitoring stress in a wind turbine blade
US7780328B2 (en) 2006-07-14 2010-08-24 Bae Systems Plc Heat distribution in a distributed lighting apparatus
GB2440954B (en) * 2006-08-18 2008-12-17 Insensys Ltd Structural monitoring
US8545179B2 (en) 2006-08-18 2013-10-01 Moog Insensys Limited Structural monitoring of wind turbine with fibre bragg grating sensors in each blade
WO2008020240A1 (en) * 2006-08-18 2008-02-21 Insensys Limited Fibre optic sensors
WO2008020242A3 (en) * 2006-08-18 2008-04-10 Insensys Ltd Structural monitoring in wind turbine blades
GB2440955A (en) * 2006-08-18 2008-02-20 Insensys Ltd Wind turbine blade monitoring
WO2008020239A1 (en) * 2006-08-18 2008-02-21 Insensys Limited Structural monitoring of wind turbine with fibre bragg grating sensors in each blade
GB2440953A (en) * 2006-08-18 2008-02-20 Insensys Ltd Monitoring wind turbine blades
WO2008020242A2 (en) * 2006-08-18 2008-02-21 Insensys Limited Structural monitoring in wind turbine blades
GB2440953B (en) * 2006-08-18 2009-09-30 Insensys Ltd Wind turbines
GB2440954A (en) * 2006-08-18 2008-02-20 Insensys Ltd Optical monitoring of wind turbine blades
WO2008101496A2 (en) * 2007-02-19 2008-08-28 Vestas Wind Systems A/S Wind turbine blade with strain sensing means, wind turbine, block sensor unit and uses hereof
EP2122161B1 (en) 2007-02-19 2017-12-13 Vestas Wind Systems A/S Wind turbine blade with strain sensing means, wind turbine, block sensor unit and uses hereof
US7896615B2 (en) 2007-02-19 2011-03-01 Vestas Wind Systems A/S Wind turbine blade with strain sensing means, wind turbine, block sensor unit and uses hereof
WO2008101496A3 (en) * 2007-02-19 2008-10-30 Vestas Wind Sys As Wind turbine blade with strain sensing means, wind turbine, block sensor unit and uses hereof
DE102007015179A1 (en) * 2007-03-29 2008-10-02 Siemens Ag Pressure measuring device and method for determining wind power on wind turbines and use of the pressure measuring device and the method
US8322984B2 (en) 2007-03-29 2012-12-04 Siemens Aktiengesellschaft Pressure measurement device and method for determining wind force at wind energy installations
US7909575B2 (en) * 2007-06-25 2011-03-22 General Electric Company Power loss reduction in turbulent wind for a wind turbine using localized sensing and control
WO2009052828A3 (en) * 2007-10-24 2009-10-29 Vestas Wind Systems A/S Wind turbine blade, wind turbine and method for manufacturing a wind turbine blade
WO2009052828A2 (en) * 2007-10-24 2009-04-30 Vestas Wind Systems A/S Wind turbine blade, wind turbine and method for manufacturing a wind turbine blade
GB2454253A (en) * 2007-11-02 2009-05-06 Insensys Ltd Monitoring strain on a wind turbine blade
WO2009056869A1 (en) * 2007-11-02 2009-05-07 Insensys Limited Placement of strain sensors in wind turbine blade
WO2009056892A1 (en) * 2007-11-02 2009-05-07 Insensys Limited Sensor array
US8336389B2 (en) 2007-11-02 2012-12-25 Moog Insensys Limited Optical fibre sensor array with temperature compensation
GB2454253B (en) * 2007-11-02 2011-02-16 Insensys Ltd Strain sensors
US8161822B2 (en) 2007-11-02 2012-04-24 Insensys Limited Placement of strain sensors in wind turbine blade
US8120759B2 (en) 2008-03-31 2012-02-21 Vestas Wind Systems A/S Optical transmission strain sensor for wind turbines
US8310657B2 (en) 2008-03-31 2012-11-13 Vestas Wind Systems A/S Optical transmission strain sensor for wind turbines
WO2009143848A2 (en) * 2008-05-30 2009-12-03 Vestas Wind System A/S A wind turbine rotor, a wind turbine and use thereof
WO2009143850A3 (en) * 2008-05-30 2010-07-15 Vestas Wind Systems A/S A wind turbine rotor, a wind turbine and use thereof
WO2009143848A3 (en) * 2008-05-30 2010-07-15 Vestas Wind System A/S A wind turbine rotor, a wind turbine and use thereof
WO2009143850A2 (en) * 2008-05-30 2009-12-03 Vestas Wind Systems A/S A wind turbine rotor, a wind turbine and use thereof
GB2461532A (en) * 2008-07-01 2010-01-06 Vestas Wind Sys As Sensor system and method for detecting deformation in a wind turbine component
US8348611B2 (en) 2008-07-01 2013-01-08 Vestas Wind Systems A/S Wind turbine having a sensor system for detecting deformation in a wind turbine rotor blade and corresponding method
WO2010001255A3 (en) * 2008-07-03 2010-11-25 Vestas Wind Systems A/S Embedded fibre optic sensor for wind turbine components
WO2010001255A2 (en) * 2008-07-03 2010-01-07 Vestas Wind Systems A/S Embedded fibre optic sensor for wind turbine components
CN102084130B (en) * 2008-07-03 2014-10-08 维斯塔斯风力系统有限公司 Embedded fibre optic sensor for wind turbine components
US8814514B2 (en) 2008-07-03 2014-08-26 Vestas Wind Systems A/S Embedded fibre optic sensor for wind turbine components
CN102084130A (en) * 2008-07-03 2011-06-01 维斯塔斯风力系统有限公司 Embedded fibre optic sensor for wind turbine components
WO2010032134A3 (en) * 2008-09-22 2010-12-02 Vestas Wind Systems A/S Wind turbine rotor blade comprising an edge-wise bending insensitive strain sensor system
WO2010032134A2 (en) * 2008-09-22 2010-03-25 Vestas Wind Systems A/S Wind turbine rotor blade comprising an edge-wise bending insensitive strain sensor system
US8234083B2 (en) 2008-09-22 2012-07-31 Vestas Wind Systems A/S Wind turbine rotor blade comprising an edge-wise bending insensitive strain sensor system
US8712703B2 (en) 2008-12-16 2014-04-29 Vestas Wind Systems A/S Turbulence sensor and blade condition sensor system
US9014863B2 (en) 2009-08-06 2015-04-21 Vestas Wind Systems A/S Rotor blade control based on detecting turbulence
US8733164B2 (en) 2010-02-04 2014-05-27 Vestas Wind Systems A/S Wind turbine optical wind sensor
EP2388476A3 (en) * 2010-04-29 2012-04-18 General Electric Company Method for temperature calibration of blade strain gauges and wind turbine rotor blade containing strain gauges
FR2988444A1 (en) * 2012-03-20 2013-09-27 Snecma DETECTION OF A FOREIGN OBJECT IMPACT AT THE ENTRANCE OF AN AIRCRAFT ENGINE
WO2013140085A1 (en) * 2012-03-20 2013-09-26 Snecma Detection and tracking of damage or impact of a foreign object on an aircraft engine fan
RU2625412C2 (en) * 2012-03-20 2017-07-13 Снекма Detection and tracking of aircraft engine fan damage or collision of foreign object with it
US9926937B2 (en) 2012-03-20 2018-03-27 Snecma Detecting and tracking damage to an aeroengine fan or an impact of a foreign object thereagainst
US11242839B2 (en) 2019-05-21 2022-02-08 Nordex Energy Se & Co. Kg Semi-finished product for a cable guide system of a wind turbine component, wind turbine component, wind turbine rotor blade and methods
IT201900008883A1 (en) * 2019-06-13 2020-12-13 Freni Brembo Spa Method and system for detecting and measuring a braking force of a vehicle brake system, using photonic sensors incorporated in a brake caliper
WO2020250187A1 (en) * 2019-06-13 2020-12-17 Freni Brembo S.P.A. Method and system for detecting and measuring a braking force of a braking system for vehicle, by means of photonic sensors incorporated in a brake caliper

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US7813598B2 (en) 2010-10-12
US7726942B2 (en) 2010-06-01
US20080279499A1 (en) 2008-11-13
EP1709416A1 (en) 2006-10-11
US20070160338A1 (en) 2007-07-12
WO2005071383A1 (en) 2005-08-04
EP1709417A1 (en) 2006-10-11
CN1910436A (en) 2007-02-07
ES2672789T3 (en) 2018-06-18
DK1709416T3 (en) 2018-06-18
CN1910436B (en) 2010-05-26
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CN1910437B (en) 2011-01-05
EP1709416B1 (en) 2018-03-07

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