WO2013190288A1 - Composant d'éolienne - Google Patents

Composant d'éolienne Download PDF

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Publication number
WO2013190288A1
WO2013190288A1 PCT/GB2013/051589 GB2013051589W WO2013190288A1 WO 2013190288 A1 WO2013190288 A1 WO 2013190288A1 GB 2013051589 W GB2013051589 W GB 2013051589W WO 2013190288 A1 WO2013190288 A1 WO 2013190288A1
Authority
WO
WIPO (PCT)
Prior art keywords
wind turbine
radar
component
turbine component
cavity
Prior art date
Application number
PCT/GB2013/051589
Other languages
English (en)
Inventor
Stephen APPLETON
Original Assignee
Vestas Wind Systems 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 Vestas Wind Systems A/S filed Critical Vestas Wind Systems A/S
Publication of WO2013190288A1 publication Critical patent/WO2013190288A1/fr

Links

Classifications

    • 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
    • F03D1/00—Wind motors with rotation axis substantially parallel to the air flow entering the rotor 
    • F03D1/06—Rotors
    • F03D1/065—Rotors characterised by their construction elements
    • F03D1/0675—Rotors characterised by their construction elements of the blades
    • 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
    • F03D80/30—Lightning protection
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q17/00—Devices for absorbing waves radiated from an antenna; Combinations of such devices with active antenna elements or systems
    • 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
    • F03D9/00—Adaptations of wind motors for special use; Combinations of wind motors with apparatus driven thereby; Wind motors specially adapted for installation in particular locations
    • F03D9/20—Wind motors characterised by the driven apparatus
    • F03D9/25—Wind motors characterised by the driven apparatus the apparatus being an electrical generator
    • F03D9/255—Wind motors characterised by the driven apparatus the apparatus being an electrical generator connected to electrical distribution networks; Arrangements therefor
    • F03D9/257—Wind motors characterised by the driven apparatus the apparatus being an electrical generator connected to electrical distribution networks; Arrangements therefor the wind motor being part of a wind farm
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
    • F05B—INDEXING SCHEME RELATING TO WIND, SPRING, WEIGHT, INERTIA OR LIKE MOTORS, TO MACHINES OR ENGINES FOR LIQUIDS COVERED BY SUBCLASSES F03B, F03D AND F03G
    • F05B2260/00—Function
    • F05B2260/99—Radar absorption
    • 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

Definitions

  • the present invention relates to composite structures such as wind turbine blades that include radar absorbing materials (RAM) for reducing the radar cross section (RCS) of the composite structure.
  • RAM radar absorbing materials
  • RCS radar cross section
  • a known problem with wind turbines is that they may interfere with radar systems and cause unwanted events (known as 'clutter') to appear on the screen of the radar operator.
  • 'clutter' unwanted events
  • some wind turbine components for example the tower, the hub and the blades are highly reflective to radar signals (i.e. electromagnetic radiation of microwave frequency).
  • radar signals i.e. electromagnetic radiation of microwave frequency.
  • the blades move, they tend to produce a radar signature similar to that of aircraft, which can make it difficult for air traffic control and other radar operators to distinguish between aircraft and wind turbines.
  • FIG. 1 shows a cross section of a prior art wind turbine blade 10.
  • the blade 10 is constructed from two aerodynamic shells, an upper shell 11 and a lower shell 12 which are formed from a glass fibre cloth and resin composite.
  • the shells 11 and 12 are supported by a tubular structural spar 13 formed from glass fibre and carbon fibre.
  • a metal cable 14 of a lightning protection system is attached to a shear web 15 of the spar 13, and runs longitudinally inside the blade 10. Whilst not shown in Figure 1 , the cable 14 is attached via straps to a plurality of lightning receptors arranged at the surface of the blade 10.
  • the spar 13 forms the primary strengthening structure of the blade 10.
  • the shells 1 1 , 12 are formed with a sandwich panel construction, in which a foam core 17 is positioned between an outer skin 18 and an inner skin 19 of glass fibre reinforced plastic (GRP).
  • GRP glass fibre reinforced plastic
  • the foam core 17 is used to separate the GRP skins 18 and 19 to keep the shell stiff in this region.
  • the shells 1 1 , 12 also include sandwich panels 20 located near the leading edge 21 of the blade 10.
  • an incoming radar signal 22 is incident upon the upper shell 11 of the blade 10.
  • the incoming radar signal 22 (referred to hereafter as the 'incident signal') is partially reflected 23 by the upper shell 11.
  • the extent to which the incident signal 22 is reflected depends upon the thickness and construction of the skin 18 and on the frequency, incidence angle and polarisation of the incident signal 22.
  • the remainder of the incident signal 22 enters the shell 11 and a small proportion of its energy is absorbed due to the intrinsic loss properties of the GRP and the foam core.
  • the majority of the incident signal 22 penetrates the shell 11 of the blade 10 and is reflected 24 by the shear web 15, the lightning cable 14 and other metallic components of the lightning protection system, and by the inner skins 19 of the shells 1 1 , 12.
  • RAM radar absorbing materials
  • RCS radar cross section
  • FIG. 2 A prior art wind turbine blade 30 with RAM incorporated in the sandwich panel regions 31 is shown in Figure 2.
  • the reflected radar signal 32 is significantly attenuated by the RAM, typically by twenty decibels or more.
  • the RAM prevents the incident radar signal 33 from penetrating the shells 1 1 , 12 of the blade 30, and hence reflections from the shear webs 15, the lightning cable, the inner skins 19 of the shells 1 1 , 12, and any other radar- reflecting objects or materials inside the blade are avoided. Further details of the RAM will now be explained briefly with reference to Figure 3.
  • FIG 3 shows an exploded sectional perspective view of part of a sandwich panel region 31 of the prior art blade 30 of Figure 2.
  • the sandwich panel 31 comprises the foam core 17, which has an inner surface 34 and an outer surface 35.
  • the core 17 is disposed between the inner skin 19 and the outer skin 18.
  • the outer surface 35 of the core 17 and the outer skin 18 face towards an exterior surface 36 ( Figure 2) of the blade 30, whilst the inner surface 34 of the core 17 and the inner skin 19 face towards an interior cavity 37 ( Figure 2) of the blade 30.
  • an impedance layer 38 is provided on the outer skin 18, and a conductive ground plane 39, which functions as a radar reflecting layer, is provided between the core 17 and the inner skin 19.
  • the foam core 17 serves as a dielectric layer between the ground plane 39 and the impedance layer 38.
  • the impedance layer 38 is a 'circuit analogue' (CA) layer, which comprises a carbon-ink circuit printed on a layer of glass-fibre which is embedded within the outer skin 18.
  • the carbon-ink circuit is represented by the array of dashes in Figure 3.
  • the outer skin 18 has been made transparent in Figure 3 so that the CA layer 38 can be seen; in reality, the CA layer 38 would not be visible through the outer skin 18.
  • the CA layer 38 forms a radar absorbing circuit in combination with the ground plane 39. When radar waves are incident upon the blade 30, the combination of the CA layer 38 and the ground plane 39 act to absorb the radar waves so that they are not reflected back to the radar source.
  • an otherwise resistive layer may be used in place of the CA layer 38.
  • Different regions of a wind turbine blade are subject to different forces. Consequently, sandwich panels at different locations within the blade structure may require different core thicknesses. Typically, the core thickness ranges from 5 mm to 50 mm.
  • the separation between the impedance layer 38 and the ground plane 39 is a key parameter for radar absorption performance, and must be carefully controlled to achieve a blade 30 having the desired absorption properties. Such careful control of the separation of these layers is made more difficult by the varying geometry of the blade 30, specifically the abovementioned variation in core thickness.
  • the sandwich panel 31 is simply too thin in comparison to the wavelength of the radar signal 33 to achieve effective RAM performance.
  • the thickness of the sandwich panel approaches half the wavelength of the radar signal 33, a condition ensues at which attenuation of the radar signal 33 is not achievable. For radar frequencies of approximately three gigahertz, this thickness has been determined to be approximately 50 mm, but will depend upon the dielectric and magnetic constants of the materials comprising the core 17 and the inner and outer skins 19, 18.
  • the split core divides the thickness of the core between inner and outer core layers disposed about an intermediate ground plane.
  • the thickness of the outer core layer determines the separation between the impedance layer and the ground plane, whilst the overall core thickness can be varied by suitable selection of the thickness of the inner core layer.
  • the inner core layer is behind the ground plane, it does not affect the performance of the RAM. Accordingly, this split core arrangement allows the overall thickness of the core to be varied without affecting the performance of the RAM and hence the RAM is able to provide consistent radar absorption performance in structures where core thickness varies.
  • split core RAM performs well, various disadvantages exist. For example, the split cores are more expensive to manufacture than standard cores and the split cores are heavier than standard cores, which is generally undesirable because blades should be as light as possible. Split cores are also unsuitable for certain regions of a blade, for example where the thickness of the composite is much less than the wavelength of the radar signals. For such regions the thickness may make it difficult to achieve high performance RAM.
  • the present invention aims to provide an alternative solution for incorporating RAM in wind turbine components, and in particular in wind turbine blades.
  • the present invention provides a wind turbine component comprising an outer shell defining an internal cavity, wherein at least a part of the outer shell is adapted to transmit incident radar signals into the cavity, and one or more reflective components inside the cavity are adapted to absorb radar signals.
  • the wind turbine component is a wind turbine blade.
  • the inventive concept can readily be applied to other components of a wind turbine, for example the nacelle, the hub or parts of the wind turbine tower.
  • the shell is adapted in part or in whole to transmit the radar signals, i.e. to allow the radar signals to pass through the shell and into the cavity.
  • the otherwise reflective components inside the cavity are adapted to absorb the transmitted radar signals.
  • RAM may be applied to these components and/or RAM may be incorporated within their structure or composition.
  • the present invention therefore provides an alternative solution to split core RAM panels when the composite thickness approaches half the wavelength of the incident radar signals. Consequently the present invention overcomes the aforementioned disadvantages of split core panels.
  • the present invention may also conveniently be employed in cases where the composite thickness is much smaller than the wavelength of the incident radar signals.
  • the adapted part of the outer shell of the present invention is adapted specifically to increase the transmission of radar signals, and preferably to maximise the transmission of radar signals.
  • the adapted part of the outer shell is of sandwich panel construction and comprises a layer of core material, which is disposed between inner and outer skin layers.
  • the core is a lightweight material such as foam or balsa.
  • the skin layers are typically made from GRP or other suitable composite material.
  • GRP GRP or other suitable composite material.
  • the adapted part of the outer shell may incorporate a frequency selective surface (FSS).
  • Frequency selective surfaces which are also referred to as 'dichroic surfaces', are known in the art and generally comprise a patterned array of conductive material, which is applied to a suitable substrate.
  • a FSS can be suitably 'tuned' to reflect or transmit electromagnetic radiation of a particular frequency or in a particular frequency range.
  • the FSS is suitably tuned to transmit radar signals, and preferably tuned to maximise the transmission of radar signals.
  • the radar signals comprise microwave radiation, and for the purposes of wind turbines, the FSS is preferably tuned to maximise transmission of radar frequencies between 1 and 10 GHz. Tuning the FSS refers to selecting a suitable pattern for the conductive array in accordance with known techniques.
  • the conductive material of the FSS may be applied to the substrate in the form of a metallic ink, such as a silver- or nickel-based ink, or in the form of a high conductivity carbon-based ink.
  • the ink may be printed onto a surface of the substrate.
  • the substrate may be a layer of glass fabric, which can be incorporated into the composite layup of the shell.
  • the substrate may be a surface of a sandwich panel core, or the FSS may be printed directly onto an outer or inner surface of the shell after the shell has been cured.
  • the FSS may alternatively be formed on the substrate by other means.
  • the FSS may be formed by etching the patterned array on a sheet of metallised polymer.
  • Such metallised sheets are readily available and generally comprise a thin sheet of polymer material, typically polyester, which includes a metal coating, typically of copper or aluminium.
  • the sheet may be bonded to a surface of the shell, and preferably the inner surface to avoid disrupting the aerodynamic properties or the appearance of the blade, and to protect the FSS from the harsh outside environment.
  • the sheet is bonded to the shell after the shell has been cured.
  • the reflective components inside the cavity are components that generally reflect incident radar signals were it not for the adaptation in accordance with the present invention.
  • components made from metal or carbon-fibre reinforced plastic (CFRP) strongly reflect radar signals GRP can also be highly reflective depending upon its thickness and the wavelength of the radar signals.
  • the reflective components may include parts of the spar such as a shear web; the lightning cable or other metal components of the lightning protection system such as the straps; and the inner skin of the blade, which is typically made from GRP.
  • Composite components inside the cavity can be adapted to absorb or attenuate radar signals by incorporating RAM into their composite structure.
  • One way of doing this is to add radar absorbing filler particles to the matrix material when the components are manufactured.
  • the radar absorbing filler particles may include carbon nanotubes and other carbon particulates, ferrites and lossy dielectrics.
  • RAM may be applied to the otherwise reflective components inside the cavity after these components have been manufactured.
  • RAM panels may be applied to the components.
  • the RAM panels preferably comprise a lightweight dielectric material such as foam.
  • the foam may include radar absorbing particles such as the filler particles described above.
  • the panels may be adapted in a similar way to the radar absorbing sandwich panels described above by way of background to the present invention.
  • an impedance layer such as a circuit analogue layer
  • a conductive ground plane such as a layer of carbon veil, may be applied to a second surface of the panel, opposite the first surface.
  • the panel forms a circuit analogue absorber, and will absorb radar signals that are incident upon the panel.
  • the RAM panels may be applied to composite components such as a shear web, or metal components such as the lightning cable, or other parts of the lightning protection system such as the metal straps that connect the lightning receptors to the lightning cable.
  • the component itself may act as the conductive ground plane of the absorber.
  • a RAM panel comprising a foam body with a CA pattern printed on the surface of the foam is applied to the lightning cable, and the lightning cable acts as the ground plane. This avoids the need to provide a separate ground plane and hence avoids the risk of arcing which may occur when conductive components are placed near components of the lightning protection system.
  • the shear web may incorporate RAM in the form of radar absorbing filler particles, and so it will be appreciated that only a relatively small panel is required, which is sufficient to cover the lightning cable.
  • a panel having an omega-shaped cross section is preferred, as this is able to suitably surround the cable whilst the legs of the omega can be bonded to the shear web.
  • the lightning receptors in prior art blades are held in place by foam mounts.
  • a suitable impedance layer such as a CA layer may be applied to these foam mounts and the metallic straps may serve as the ground plane. This conveniently allows the RCS of existing components to be reduced without requiring any substantial modification to the structure or arrangement of these components.
  • a wind turbine comprising the wind turbine component described above, and a wind farm comprising such a wind turbine.
  • the invention also provides a method of reducing the radar cross section of a wind turbine component, the component comprising an outer shell defining an internal cavity, and the method comprising optimising the transmission of incident radar signals through at least part of the outer shell and into the cavity and optimising the absorption of the radar signals by components inside the cavity.
  • Optional and preferred features described above in relation to the apparatus apply equally to the method.
  • the method may comprise adapting the outer shell to optimise the transmission of incident radar signals through the shell and into the cavity.
  • the method may comprise applying a suitably-tuned FSS to the outer shell.
  • the method may comprise applying the FSS to a layer of glass fabric and incorporating said layer of glass fabric in the laminate layup of the outer shell during manufacture of the shell.
  • the method may comprise applying the FSS to an inner surface of the outer shell after the shell has been manufactured.
  • the method may comprise incorporating radar absorbing particles within the structure of the reflective component during manufacture of said component.
  • the method may comprise applying RAM to the reflective component inside the cavity.
  • the method may comprise applying a RAM panel to one or more surfaces of the component.
  • Figure 1 shows a cross section of a prior art wind turbine blade
  • Figure 2 shows a cross section of a prior art wind turbine blade incorporating radar absorbing material within a sandwich panel region of the shell of the blade
  • FIG. 3 shows an exploded sectional perspective view of part of the sandwich panel region of the prior art blade of Figure 2.
  • Figure 4 shows a cross section of a wind turbine blade according to a first embodiment of the present invention
  • Figure 4A is an enlarged schematic view of part of a sandwich panel of the blade of Figure 4; and Figure 5 shows a cross section of a wind turbine blade according to a second embodiment of the present invention.
  • a wind turbine blade 50 according to a first embodiment of the present invention has a basic construction similar to the wind turbine blade 10 described by way of background with reference to Figure 1.
  • the wind turbine blade 50 has been modified so that part of the outer shell 1 1 , 12 of the blade 50 transmits radar signals 52a, 52b, i.e. rather than absorbing or reflecting the radar signals 52a, 52b, the modified shell 1 1 , 12 allows the radar signals 52a, 52b to pass through into the internal cavity 37 of the blade 50.
  • a radar absorbing panel 54 is used to cover the lightning cable 14 and one of the highly reflective shear webs 15 of the spar structure 13.
  • the shell 1 1 , 12 of the blade 50 comprises regions of sandwich panel construction.
  • sandwich panel construction The principles of sandwich panel construction have already been discussed by way of background and so will not be repeated here.
  • sandwich panel regions Four sandwich panel regions are shown in Figure 4: a first pair of sandwich panels 56 (hereinafter the 'leading edge panels') is incorporated respectively in the upper and lower shells 1 1 , 12 between the leading edge 21 of the blade and the spar structure 13 and a second pair of panels 58 (hereinafter the 'trailing edge panels') is incorporated respectively in the upper and lower shells 1 1 , 12 between the spar structure 13 and the trailing edge 16 of the blade 50.
  • first pair of sandwich panels 56 hereinafter the 'leading edge panels'
  • second pair of panels 58 hereinafter the 'trailing edge panels'
  • the trailing edge panels 58 are adapted to transmit radar signals 52a, 52b, whilst the leading edge panels 56 are adapted to absorb / attenuate radar signals 52c in the same way as described above by way of background in relation to Figures 2 and 3.
  • the electrical thicknesses of the leading edge panels 56 are not close to half the wavelength of the incident radar signals 52a, 52b and are hence suitable for single-core RAM sandwich panels, whereas the trailing edge panels 58 are thicker, with a thickness approaching half the wavelength of the incident radar signals 52a, 52b, and so split core RAM panels would normally be used here. It will be appreciated that the present invention provides an alternative to split core RAM panels.
  • the panel 58 comprises a foam core 60 disposed between inner and outer GRP skins 62 and 64 respectively.
  • the outer GRP skin 64 of the sandwich panel 58 comprises a frequency selective surface (FSS) 66 in the form of a patterned array of conductive material, which is printed on a layer of glass fabric using highly conductive silver-based ink.
  • FSS frequency selective surface
  • the FSS layer 66 is included in the laminate layup of the shell 11 when the shell 11 is manufactured, which results in the FSS layer 66 becoming embedded in the outer GRP skin 64.
  • the sandwich panel 58 of the lower shell 12 has an identical structure.
  • the FSS layer 66 may be embedded in the inner skin 62.
  • the FSS 66 is tuned to transmit radar signals of approximately 3 GHz, which results in the sandwich panels 58 being substantially transparent to radar signals of this frequency.
  • the FSS 66 may be suitably tuned to transmit any desired frequency.
  • the radar absorbing panel 54 is bonded to a surface of the shear web 15 and also covers the lightning cable 14, which is attached to the shear web 15.
  • the panel 54 is made mainly from lightweight foam or any suitable material.
  • a circuit analogue (CA) layer 68 is provided on a first surface 70 of the panel 54 facing the trailing edge 16 of the blade 50.
  • the circuit analogue layer 68 is printed on the first surface 70 using carbon-based ink.
  • a reflective ground plane 72 in the form of a layer of carbon veil is provided on a second surface 74 of the panel facing the leading edge 21 of the blade 50.
  • the ground plane 72 may comprise a printed reflector layer or a FSS polymer layer.
  • radar signals 52a and 52b are transmitted by the modified trailing edge panels 58 into the cavity 37.
  • the radar signal 52a is incident upon the shear web 15 and the lightning cable 14 and is absorbed by the radar- absorbing panel 54, which covers these components.
  • the radar signal 52b is not incident upon these components and so passes straight through both shells 1 1 , 12 of the blade 50. Some internal reflection of the signal 52b may occur from the inner skin 19, however these reflected signals should be largely absorbed by the RAM inside the cavity 37.
  • the leading edge panels 56 At the leading edge 21 of the blade 50, the leading edge panels 56 largely attenuate incident radar signals 52c instead of transmitting those signals.
  • FIG. 5 shows a wind turbine blade 75 in accordance with a second embodiment of the present invention.
  • a smaller radar- absorbing foam panel 76 is used to cover just the lightning cable 14.
  • This smaller panel 76 is omega-shaped in cross section, which is a convenient shape because the round part 77 of the omega profile covers the lightning cable 14 whilst the legs 78 of the omega profile provide a convenient surface for bonding the panel 76 to the shear web 15.
  • a CA pattern 80 is printed on a first surface 82 of the panel 76, which generally faces the trailing edge 16 of the blade 75.
  • the lightning cable 14 itself forms a reflective ground plane for the radar absorbing panel 76, which avoids the need to provide a separate conductive ground plane such as a layer of carbon veil. This advantageously avoids the risk of arcing, which can occur when conductive material is placed near to the lightning cable 14.
  • the omega panel 76 may be made from plastic to which radar absorbing filler particles are added.
  • These filler particles may include carbon nanotubes and other carbon particulates, ferrites and lossy dielectrics The thickness of the profile and the type and concentration of the filler particles are all chosen to produce RAM performance at the chosen frequency range.
  • the RCS of the shear web 15 in this embodiment is reduced by incorporating radar absorbing filler particles in the composite structure of the shear web 15. These particles may include carbon nanotubes and other carbon particulates, ferrites and lossy dielectrics, and are included in the resin used to manufacture the shear web 15. Alternatively, a circuit analogue method may be used to adapt the shear web.
  • the trailing edge sandwich panels 58 in the second embodiment are modified to transmit radar signals in the same way as those of the first embodiment described above with reference to Figure 4.
  • the blades described above by way of example have RAM sandwich panels at the leading edge that are designed to absorb radar signals
  • the leading edge panels may have a similar construction to the trailing edge panels, i.e. constructed to optimise the transmission of radar signals.

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  • Engineering & Computer Science (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Sustainable Development (AREA)
  • Sustainable Energy (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Wind Motors (AREA)
  • Aerials With Secondary Devices (AREA)
  • Radar Systems Or Details Thereof (AREA)

Abstract

L'invention concerne un composant d'éolienne, qui comporte une enveloppe extérieure délimitant une cavité interne. Au moins une partie de l'enveloppe extérieure est conçue pour transmettre des signaux radar incidents dans la cavité, et un ou plusieurs composants réfléchissants se situant à l'intérieur de la cavité sont conçus pour absorber des signaux radar.
PCT/GB2013/051589 2012-06-21 2013-06-19 Composant d'éolienne WO2013190288A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB1210960.9 2012-06-21
GB1210960.9A GB2503260A (en) 2012-06-21 2012-06-21 Wind turbine component with radar transmitting and absorbing parts

Publications (1)

Publication Number Publication Date
WO2013190288A1 true WO2013190288A1 (fr) 2013-12-27

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DK178792B1 (en) * 2014-11-11 2017-02-06 Gen Electric Channel Structure for a lynbeskyttelseskabel a vindmøllerotorvinge
CN107035628A (zh) * 2015-11-24 2017-08-11 歌美飒创新技术公司 包括装配有雷达吸收材料的防雷系统的风力涡轮机叶片
CN109633286A (zh) * 2018-12-03 2019-04-16 成都飞机工业（集团）有限责任公司 一种具有电磁测试特性的载体

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FR3023420B1 (fr) * 2014-07-03 2017-12-08 Ineo Defense Procede de realisation d'une paroi composite et paroi composite associee
DE102018100302A1 (de) * 2018-01-09 2019-07-11 Wobben Properties Gmbh Windenergieanlagen-Rotorblatt

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GB2458998A (en) * 2008-04-11 2009-10-14 Philip Charles Bond Wind turbine blade with symmetrical tip, reflected radar phase change layer, tower edge and radar clutter processing methods.
WO2010122351A2 (fr) * 2009-04-23 2010-10-28 Vestas Wind Systems A/S Améliorations apportées ou se rapportant à des structures composites
WO2012056230A1 (fr) * 2010-10-26 2012-05-03 Vestas Wind Systems A/S Composant d'éolienne comprenant un matériau absorbant les ondes radar
EP2463515A1 (fr) * 2010-12-08 2012-06-13 Ineo Defense Pale d'éolienne avec surface équivalente radar réduit et éolienne munie d'une telle pale

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2458998A (en) * 2008-04-11 2009-10-14 Philip Charles Bond Wind turbine blade with symmetrical tip, reflected radar phase change layer, tower edge and radar clutter processing methods.
WO2010122351A2 (fr) * 2009-04-23 2010-10-28 Vestas Wind Systems A/S Améliorations apportées ou se rapportant à des structures composites
WO2012056230A1 (fr) * 2010-10-26 2012-05-03 Vestas Wind Systems A/S Composant d'éolienne comprenant un matériau absorbant les ondes radar
EP2463515A1 (fr) * 2010-12-08 2012-06-13 Ineo Defense Pale d'éolienne avec surface équivalente radar réduit et éolienne munie d'une telle pale

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DK178792B1 (en) * 2014-11-11 2017-02-06 Gen Electric Channel Structure for a lynbeskyttelseskabel a vindmøllerotorvinge
US10316827B2 (en) 2014-11-11 2019-06-11 General Electric Company Conduit assembly for a lightning protection cable of a wind turbine rotor blade
CN107035628A (zh) * 2015-11-24 2017-08-11 歌美飒创新技术公司 包括装配有雷达吸收材料的防雷系统的风力涡轮机叶片
CN109633286A (zh) * 2018-12-03 2019-04-16 成都飞机工业（集团）有限责任公司 一种具有电磁测试特性的载体

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