CN103926061A - Deformation monitoring method and system for measuring tensile strain of cable - Google Patents

Abstract

The invention provides a deformation monitoring method and system for measuring the tensile strain of a cable. The deformation monitoring method comprises the following steps that at least one cable is provided, wherein the cable comprises a strain sensor and at least two longitudinal structure elements, the strain sensor extends in the longitudinal direction of the cable and comprises strain optical fibers arranged in the bending neutral region, the bending neutral region wraps and comprises a bending neutral longitudinal axial line of the cable, at least one longitudinal structure element is a core comprising an electric conductor, and the strain sensor is in mechanical connection with at least one longitudinal structure element at least in the strain state; a first optical signal is introduced into the strain optical fibers; brillouin scattering light emitted by the strain optical fibers is detected; spectral changes of the scattering light are analyzed so that the tensile strain of the cable can be measured at least.

Description

The distortion that is used for the tensile strain of measuring cable monitors method and system

The application is that to be called " having the cable of strain transducer and surveillance and the method for detection of the strain at least one cable ", international filing date be that May 27, international application no in 2009 are that PCT/EP2009/056428, national applications number are the divisional application of 200980160074.9 application for a patent for invention to name.

Technical field

The present invention relates to a kind of cable, this cable has the integrated strain transducer of the measurement that is specially adapted to Static and dynamic tensile strain.

The invention still further relates to a kind of at least measuring the supervision method and system of strain of at least one cable.

The invention still further relates to a kind of surveillance for detection of the strain in many cables and method.Particularly, the present invention relates to monitor by Brillouin backscattering technology the surveillance and the method that are arranged on many cables in movable equipment.

Background technology

Become to withstand harsh environmental baseline and high mechanical stress by specific design in particular for heavy-duty applications and/or for the cable of movable fixture (such as removable portal crane, ship to shore container crane, ship decrater, paver and tunnel winning equipment), such as tension force and moment of torsion.As the other example of the cable for heavy-duty applications, be conventionally arranged on physically in restricted region and in hostile environment for supplying current to the subsurface pump cable of submersible electric pump system of deep-well, often contact with corrosivity well fluid.Typically, above-mentioned cable is designed to firm and flexible.At this instructions, when the cable of mentioning for heavy-duty applications, and especially but while being not exclusively intended for use in the cable of movable fixture, we will be commonly referred to heavy cable.

The example of heavy cable is provided in DE3934718, and DE3934718 has described the cable that pulls with armouring for the cutter-loader of mine.

WO01/78086 discloses a kind of especially for the cable of the picking up system such as crane or commodity shelf system.This cable comprises core, and this core comprises the first conductor, and this first conductor is born base material by the first stress and surrounds and be embedded in the first stress completely and bear in base material.At least one other layer is arranged in that the first stress bears base material around and have at least one other conductor in this other layer, and this at least one other conductor is born base material by the second stress and surrounds and be embedded in the second stress completely and bear in base material.Strain in cable is born base material and be it is said that allowable stress is distributed on whole piece cable and therefore significantly reduces spiral advancing effect.

Tensile load in removable cable and distortion can be wrapped in the mandatory guidance around spool and during the unwinding stage or produced by the collection of the cable in basket (for example,, for paver cable) by cable.Be wound around and the unwinding stage discontinuous and normally unexpected (for example, in the time being caused by the tangential movement of crane) typically, therefore on cable, apply significant dynamic tensile load, and therefore on the single conductor in cable, apply significant dynamic tensile load.In addition,, for other system of cable movement, such as pulley system and treatment (tender) system, conventionally on cable, apply during operation high tensile load.

The excessive prolongation of cable can cause that tensile load is delivered to electric conductor, therefore damages electric conductor.Tensile load excessive and/or that delay can cause the permanent prolongation of cable, and this will shorten the life-span of cable.

US5,767,956 descriptions provide monitoring arrangement with backscattering Brillouin light, no matter optical fiber is normal or close to breaking, this monitoring arrangement can both be observed in real time.By utilizing of optical fiber core in optical cable, this device uses optical time domain reflectometer (OTDR) to monitor the Brillouin scattering exciting.Hint about the use in cable is not provided.

WO08/073033 has described strain in a kind of optical fiber that is connected to or is incorporated to cable by measurement for monitoring the system of bending and strain of the cable that is connected to mobile offshore platform.Bending in cable will change the optical property of fiber by produce strain and this strain in optical fiber.The change of optical property can be measured by optical time domain reflectometer (OTDR) or optimal frequency domain reflectometer (OFDR).

This document is not in the face of protecting strain transducer to avoid exterior mechanical stress to avoid the damage of sensor and the problem of the long-term reliability that guarantee is measured.On the contrary, the application state exist be embedded in or be connected to the optical fiber of cable can vitiable danger and therefore propose to be equipped with unnecessary fiber for cable.In addition, do not mention fiber and want the problem of the strain transfer between measured cable.As the possible position for fiber, mention the space between armor wire.

US2004/0258373 describes one can be embedded in buildings, heaving pile or ducted composite cable, and this composite cable comprises the optical devices for monitoring temperature and strain.This cable comprises outer protection sheath and for monitoring the optical devices of temperature and strain, described optical devices are in described outer protection sheath and comprise: the first pipe, this first pipe comprises at least the first optical fiber to monitor temperature, described the first optical fiber is loosely in described the first pipe and comprise that at least one is called the reflecting part of Bragg grating, this first pipe comprises at least the second optical fiber, this at least the second optical fiber comprises at least one Bragg grating to monitor strain, described cable is characterised in that, described the second optical fiber is outside at described the first pipe, described optical devices also comprise for fastening described the second fibre-optic device.

The applicant has been noted that this document does not openly have integrated strain optical fibre transducer or has the cable of integrated temperature sensor.Disclosed cable is composite cable, and this composite cable can comprise power cable, but with fiber separation for strain and temperature monitoring.

EP0203249 discloses medium voltate (6 to 60kV) cable, and this cable comprises at least one temperature and/or tension pick-up optical fiber.

The applicant observes, and the disclosed strain transducer optical fiber being integrated in cable can be subject to the Bending Influence (depending on the position of optical fiber in cable and/or the bending amount of cable, particularly in the time exceeding a certain value) of cable significantly.

Chen Xihao and Huang Junhua, in Strain Transfer Capability of Strain Sensing Optical Fiber Cable and its Measurement Method, published in the Proceedings of the57 ^thinternational Wire & Cable Symposium (2008), pages424-428 analyzes the different structure of the sensing optical fiber cable cable of the strain of sensing associated apparatus or system (, for).The compactedness of the layer in straining and sensing optical fiber cable is considered to very important and can be described by the peeling force between cable floor and strain transfer ability (, can not reducing to be delivered to from cable outer layer the maximum strain of internal fiber).

This document is not mentioned any application that disclosed sensing optical fiber cable monitors to the cable of electric power or cable.

WO07/107693 discloses a kind of optical fiber cable, this optical fiber cable comprise strain transfer member, through strain transfer member arrange central optical fiber and by the tight sheath of central optical fiber and strain transfer member mechanical attachment.The strain that strain transfer member stands is delivered to central optical fiber by tight sheath.

The document is not faced the problem of the cable with optical fibre transducer.

The applicant is particularly suitable for heavy-duty applications in the face of how to realize, and be more particularly suitable for the problem of the cable of movable fixture, this cable is by the control of the tensile strain that allows cable to be subject to during operation, and preferably allow the real time monitoring of this tensile strain, ensure the long-term reliability of measuring simultaneously.

Especially, the applicant is treated carries out the problem of measuring in cable by sensor, and this sensor keeps not substantially being subject to except being applied to the exterior mechanical stress influence the tensile strain on cable.

Summary of the invention

Due to the high mechanical stress that operating period applies, the typical life of heavy cable (such as for application or the crane equipment of digging up mine) is normally relatively short, and depends on that concrete application can change between the several years at several months.The applicant observes, will be advantageously, the heavy cable that can be monitored in its operating period is provided.By understanding the time-evolution of cable status, can carry out the effective periodic maintenance of cable, for example, can regulate the Electronic Control parameter of the automatic system of guide reel fault and/or adjusting movable equipment.

Making regular check on of cable status can be " off-line ", cable is not used or is even removed from its equipment mounted thereto, but in fact, because this inspection is not carried out in the loss of the working time stopping due to necessity of the equipment that comprises cable or device conventionally.

Will be particularly advantageously, cause the dynamic event of elastic strain peak value at cable duration of work record, but this dynamic event can be due to the tired cable that damages.And this supervision can prevent less desirable inactive event and save relevant cost.

Target of the present invention is to provide a kind of cable with strain transducer, and this strain transducer can provide reading for the measured prolongation of sizable scope, this sizable scope in particular from 0.1% to 1%, preferably from-0.2% to 1%.Also can measure higher prolongation value, for example, reach 2% or even arrive 4%.

In this case, may occur the reduction of the speed that data read, this " in real time " that can affect the data of the cable from being monitored is collected.

Another target of the present invention is to provide a kind of cable with strain transducer, and this strain transducer is measured dynamic tensile load, especially monitors the strain breaking out in the local part of length of cable, therefore determines the damage that fatigue causes.

Other target of the present invention is to provide a kind of surveillance, and this surveillance is for detection of the permanent damages of the cable that may cause by inter deterioration or by unsuitable use (for example,, by not meeting the use of the recommendation that cables manufacturing person provides).

Another target of the present invention is to provide a kind of surveillance, and this surveillance is especially the tensile strain that is arranged on many cables of the heavy cable of movable equipment at least monitoring.

Usually and according on the one hand, this scheme relates to a kind of cable, this cable comprises at least two vertical structure elements and for monitoring along the optical fiber strain transducer of the tensile strain of the length of cable.This strain transducer comprises the optical fiber extending along the length of cable.The optical fiber of strain transducer also will be called strain optical fiber below.

According to a further aspect in the invention, provide a kind of at least measuring the distortion supervision method of tensile strain of at least one cable, said method comprising the steps of: at least one cable is provided, described at least one cable comprises: strain transducer, described strain transducer is extending longitudinally and comprise the strain optical fiber being arranged in bending neutral region along described cable, and described bending neutral region surrounds and comprise the neutral longitudinal axis of bending of described cable; At least two vertical structure elements, at least one in described at least two vertical structure elements is the core that comprises electric conductor, wherein said strain transducer at least in strain regime with described at least two vertical structure elements at least one mechanical attachment; The first optical signalling is introduced to described strain optical fiber; Detect the Brillouin scattering sending from described strain optical fiber; With the spectrum change of analyzing in described scattered light, at least measure the tensile strain of described at least one cable.

According to another aspect of the invention, provide a kind of at least measuring the distortion surveillance of tensile strain of at least one cable, described distortion surveillance comprises: cable, described cable comprises: strain transducer, described strain transducer is extending longitudinally and comprise strain optical fiber along described cable, described strain optical fiber has the close end and the distal portion that are arranged in bending neutral region, and described bending neutral region surrounds and comprise the neutral longitudinal axis of bending of described cable; At least two vertical structure elements, at least one in described at least two vertical structure elements is the core that comprises electric conductor, wherein said strain transducer at least in strain regime with described at least two vertical structure elements at least one mechanical attachment; And sample devices, described sample devices is used for the spectrum change of the Brillouin scattering of measuring described strain optical fiber, and described sample devices connects with the fibre-optic at least described close end optics of described strain, to light is introduced to described strain optical fiber.

According to another aspect of the invention, provide a kind of at least measuring the distortion surveillance of tensile strain of many cables, described distortion surveillance comprises: for measuring the sample devices of spectrum change of Brillouin scattering, described sample devices comprises the first optics input/output end port and the second optics input/output end port, and described the first optics input/output end port is used for sending the first optical signalling and described the second optics input/output end port for sending the second optical signalling; with first group of many cable, described first group of many cable comprise the first cable and last cable, each cable in described first group of many cable comprises strain transducer and temperature sensor, described strain transducer comprises strain optical fiber, described temperature sensor comprises temperature optical fiber, described strain transducer and temperature sensor are extending longitudinally along corresponding cable, described strain optical fiber and temperature optical fiber have close end and distal portion, the fibre-optic close end of described strain and the fibre-optic close end of temperature are positioned at the close end place of corresponding cable, wherein: the fibre-optic distal portion of described strain of each cable and the fibre-optic distal portion of described temperature each other optics are connected, the first optics input/output end port optical communication of the fibre-optic close end of strain of the first cable in described first group of many cable and described sample devices, and the second optics input/output end port optical communication of the temperature optical fiber of the last cable in described first group of many cable and described sample devices, and the fibre-optic close end of the temperature of described the first cable is connected with the fibre-optic close end optics of strain of described last cable, to form optical fiber ring, in described optical fiber ring, the described strain optical fiber of each cable in described many cables and the first optics input/output end port of described temperature optical fiber and described sample devices and the second optics input/output end port optical communication, and described the first optical signalling and the second optical signalling enter described optical fiber ring along contrary direction.

In this manual, term " vertical structure element " represents substantially partly to complete structure along the length of cable cable extending longitudinally.As according to becoming clearly, contribute to the electric transportation function of cable according to the vertical structure element of this instructions and claim below.

Described at least two vertical structure elements that cable comprises comprise at least one cable core.

Term " core " represents to comprise such as at least one electrical conductivity element of electric conductor and typically comprises the half-done structure of the cable of at least one insulation course that surrounds electric conductor.In typical construction, electric conductor comprises multiple stranded wires.

The applicant has realized that the mechanical attachment between vertical structure element and the optical fiber of strain transducer by ensureing cable, and especially mechanical fit, and strain is delivered to strain optical fiber from the vertical structure element that will be monitored.By " mechanical fit ", mean two or more parts and substantially move as a whole or tolerate adaptability to changes.Just now the mechanical fit of describing allows to obtain the cable that the reliable readings of the Static and dynamic tensile load standing can be provided in extending relatively on a large scale.According to an aspect of the present invention, strain transducer is embedded in strain transfer filler, and this strain transfer filler is by least one mechanical attachment of at least two vertical structure elements of sensor and cable.

The length that tensile strain is expressed as cable is increased in the number percent in initial length, Δ L/L, and wherein L is length, extends as number percent is linear.In the time that cable for example, is forced to due to external force (, tensile load) stretch along its longitudinal direction, tensile strain occurs.

The applicant has realized that strain transducer should be integrated in cable and be arranged to and is not damaged by the bending with its minimum bending radius of cable to maintain substantially.Especially, the applicant understands, the optical fiber that strain transducer comprises should be positioned at the bending neutral region that is called below neutral region, and this bending neutral region is extending longitudinally and have an xsect that the neutral axis about cable extends symmetrically substantially along cable.

As used herein, term " neutral region " is intended to describe axis (" neutral axis ") region around, and at this axis place, the prolongation that bending causes is minimum.Neutral axis can be defined as along the imaginary line of the length of cable, at this imaginary line place, at cable through by bending in the situation that, there is not significant linear deformation and in strain transducer bending stress be small.Preferably, cable design becomes to make neutral axis be arranged in a position, in this position, acts on torque on cable and determine the small extend longitudinally of sensor fiber.

(it is conventionally corresponding to minimum profile curvature radius ρ for the minimum bending radius of given cable _min, cable allows this minimum profile curvature radius to avoid any permanent damages), neutral region can be defined as due to be not less than ρ _minbending, the strain transducer of radius-of-curvature stand to be not more than 2%, and be preferably not more than the region of 1% prolongation.The layout of strain optical fiber in neutral region prevents that it is because cable bend breaks or permanent damages.

In round cable, have in the cable of circular symmetry xsect, neutral region is the radial zone around neutral axis in the cross sectional planes of cable.In a preferred embodiment, in the time mentioning round cable, neutral axis is the central longitudinal axis of cable.Preferably, strain transducer is no more than 0.02 ρ along cable arrangements leaving neutral axis _min, and be more preferably no more than 0.01 ρ _minradial distance in.

According to one side, the present invention relates to a kind of cable, this cable comprises: strain transducer, described strain transducer is extending longitudinally and comprise the strain optical fiber being arranged in bending neutral region along described cable, and described bending neutral region surrounds and comprise the neutral longitudinal axis of bending of described cable; At least two vertical structure elements, at least one of described at least two vertical structure elements is the core that comprises electric conductor, wherein said strain transducer is embedded in strain transfer filler, and this strain transfer filler is by least one and strain transducer mechanical attachment of at least two vertical structure elements.By cable of the present invention, at least, in strain regime, at least one strain transfer standing of at least two vertical structure elements is to strain transducer.

Heavy cable design becomes to bear side load and the tension force of the vertical structure element in compression cable.The applicant observes, will be advantageously, and strain transducer keeps not affected by the lateral compression of cable, and this lateral compression can cause the light loss due to microbend in the time affecting strain optical fiber.In addition,, in the time that the optical fiber of strain transducer is compressed, can changes improperly tensile strain into along a part for the side load applying transverse to the direction of cable longitudinal axis and change.Especially, observe, in the time that edge vertically or conventionally applies lateral compression transverse to the direction of cable longitudinal axis, if lateral compression is delivered to optical fiber, the parts that are parallel to strain fibre axis can cause the strain variation along that axis.

Preferably, select the neutral axis of cable to can obviously not show the lateral compression being subject to along the direction of the horizontal longitudinal direction in cable.The applicant has been found that advantageously, with protecting sheath to surround strain optical fiber to improve the mechanical resistance to side load, the optionally optical fiber of buffering of the direct contacting strain sensor of described protection sheath.Preferably, protection sheath comprises the compound substance that fiber is strengthened.

Cable typically stands one or more thermal treatment during it is manufactured, especially solidification process, and this solidification process relates to the thermal treatment that continues several minutes under the representative temperature of about 150-200 DEG C.The applicant has been noted that, preferably, strain transfer filler and strain transducer comprise that tolerance strain transducer is integrated in the material of the solidification process occurring during the manufacture of cable wherein, maintain: the elastic property of (1) strain transducer simultaneously, at least have in the scope of elastic performance at cable, this elastic property realizes the reversibility of strain transducer and there is no the permanent strain of strain transducer, and (2) adhere to or high frictional resistance so that sustaining layer and cable element to undesired slippage between mechanical fit.

Preferably, the compound substance that protection sheath is strengthened by fiber is made, and wherein reinforcing fibre is carbon, graphite, boron, aromatic poly amide or glass fibre; The polymkeric substance of embedding reinforcing fibre is preferably cross-linked resin, for example, and undersaturated polyester, such as vinyl esters or epoxy resin.

Preferably, strain transfer filler is based on elasticity material, more preferably based on thermo-setting elastomer.It is flexible that strain transfer filler at least has in the range of strain of elastic performance at cable.

The applicant has been noted that advantageously, is cable set temperature sensor.

The operating temperature of heavy cable can be from 90 DEG C of-50 DEG C of variations, and wherein-50 DEG C is the minimum environment temperature of duration of work, and 90 DEG C is the operating period maximum temperature that reaches of electric conductor.Longitudinal local the increasing (that is, increasing without peak) that crosses over the internal temperature of the average cable in interval sometime can be indicated the existence of damage, and this damage causes the increase of for example conductor resistance and local Joule loss.In addition, electric load affects overall cable temperature, and therefore, the Arrhenius model that reference prediction accelerates due to the inefficacy that temperature increases, the supervision of cable temperature allows the residual life of prediction cable and therefore allows the in good time planned replacement of cable.

Temperature monitoring can be used for eliminating the strain causing due to the temperature effect in the optical analysis based on Brillouin.

In order to carry out the only temperature survey of the hot state impact of strained fibre-optic fibrous glass, optical fiber should not have mechanical stress, and especially, the tensile strain that should substantially not be subject to it to be integrated in cable wherein affects.In some preferred embodiments, temperature sensor is integrated in cable, and wherein temperature sensor comprises optical fiber, and this optical fiber is loosely inserted in the module extending longitudinally twisting together with the vertical structure element of cable.In this structure, the degree (, the amount of the unnecessary fibre length in pipe) that cable is loose makes the maximum extension of expection of cable (with fiber containing pipe) by full remuneration, makes not have obvious strain transfer to temperature sensing optical fiber.

In some preferred embodiments, cable is have the round cable of circular cross section substantially and comprise with respect to strain transducer and be radially arranged at least three outside vertical structure elements.

Brief description of the drawings

Now will with reference to accompanying drawing, the present invention be described more fully below, embodiment more of the present invention but not all shown in the drawings.The accompanying drawing that embodiment is shown is the schematic diagram of not to scale (NTS).

For the object of this description and claims, unless otherwise noted, all numbers of expressing quantity, amount, number percent etc. will be understood to be modified by term " approximately " in all cases.And all scopes comprise disclosed minimum and maximum point and comprise any intermediate range wherein that can specifically enumerate or specifically not enumerate here.

Fig. 1 a is the perspective illustration of cable according to an embodiment of the invention.

Fig. 1 b is the schematic sectional view of the cable shown in Fig. 1 a.

Fig. 2 a is the perspective illustration of the strain transducer that uses in cable of the present invention.

Fig. 2 b is the schematic sectional view of the strain transducer shown in Fig. 2 a.

Fig. 3 is the schematic sectional view of cable according to other embodiments of the present invention.

Fig. 4 is the schematic sectional view of cable according to still another embodiment of the invention.

Fig. 5 is the schematic sectional view of cable according to still another embodiment of the invention.

Fig. 6 is the schematic sectional view of flat cable according to other embodiments of the present invention.

Fig. 7 is schematic diagram, for the principle of operation of the backscatter technique based on Brillouin of cable is according to an embodiment of the invention shown.

Fig. 8 is the diagrammatic representation that is arranged on according to an embodiment of the invention the strain of many heavy cables in movable equipment and the surveillance of temperature.

Fig. 9 is the partial side view of C-C along the line, and the heavy duty crane of the surveillance of Fig. 8 is shown.

Figure 10 is schematic diagram, and the principle of operation of the surveillance of many heavy cables in embodiments of the invention is shown.

Figure 11 is the diagrammatic representation of the surveillance of the strain that is arranged on many heavy cables in movable equipment according to other embodiments of the present invention and temperature.

Figure 12 is schematic diagram, and the principle of operation of the surveillance of many heavy cables in other embodiment of the present invention is shown.

Embodiment

Fig. 1 a and 1b illustrate respectively skeleton view and the cut-open view of cable according to an embodiment of the invention.The cable illustrating of the present embodiment can be suitable for heavy-duty applications, is more specifically suitable for movable fixture.Cable 1 is the round cable that comprises three cores 2, and these three core diameters are visible in Fig. 1 a to the central longitudinal axis Z(that is arranged in cable) around.Core 2 can provide three-phase power transmission.Cable 1 can be low or medium voltate cable, and wherein low-voltage represents until the voltage of 1kV and medium voltate represent the voltage from 1kV to 60kV.Each core 2 comprises electric conductor 12, for example, and by the copper conductor a branch of zinc-plated or that exposed copper electric wire forms twisting together according to conventional methods.In the radially outer position with respect to each electric conductor 12, sequentially arrange internal semiconductive layer 13, insulation course 16, outside semiconductive layer 17.Internal semiconductive layer 13, insulation course 16 and outside semiconductive layer 17 are made up of the material based on polymkeric substance, and this material based on polymkeric substance can be stacked to be extruded or be jointly expressed on conductor 12.Insulation course 16 can be the ethylene propylene rubber (EPR) being for example cross-linked; Inside and outside semiconductor layer 12 and 17 can be EPR, ethylene/propylene/diene terpolymers (EPDM) or its potpourri that is for example filled with the conductive filler of suitable amount, and this conductive filler can be typically carbon black.

Alternatively, in the situation that mode of operation allows, insulation course and semiconductor layer can be by making such as the thermoplastic compound based on polyacrylic compound.

In some applications, cable core 2 comprises at least one metal screen layer 22 in the radially outer position with respect to outside semiconductive layer 17.

The above description that should be appreciated that core 2 only represents the one of the possible structure of the core that cable comprises, this core can be for the phase core of electric power transfer or ground connection, for transporting the core of control signal or transporting electric power and the core of control signal conventionally.

According to feature of the present invention, cable 1 comprises optical fiber strain transducer 5.

Because heavy cable stands the fact of mechanical stress frequently at their life period, the applicant has realized that suitable especially, and strain transducer is positioned in cable and makes cable bend to being not less than minimum profile curvature radius ρ _minnot breakdown strain optical fiber of any radius-of-curvature, this minimum profile curvature radius can be bending corresponding to cable and there is no a least radius of permanent damages.Cable bend causes prolongation in strain transducer.Observe, to be not less than ρ _minradius-of-curvature cable bend (longitudinal strain that at this moment, bending causes be less than typically be 1 or 2% strain testing in be applied to the strain of fiber) breakdown strain sensor not conventionally.

Keep the region of the cable of the length extension of unspoiled cable to be defined as (bending) neutral region of cable due to cable bend along strain optical fiber.In round cable, in the cross sectional planes of cable, neutral region is the radial zone about neutral axis, and in the present embodiment, this neutral axis is corresponding to central longitudinal axis Z.

Preferably, in the neutral region of optical cable, strain transducer is due to ρ _minbending and stand to be equal to or less than 2%, be more preferably equal to or less than 1% prolongation.

The applicant observes, and is heavy cable, the ρ specifying in particular for the application in movable equipment _minvalue can be relatively low, for example, 250mm, and therefore, in order to ensure the bending resistance of strain transducer, neutral region should have the relatively little radial distance that leaves central longitudinal axis, for example, is not more than 5mm.For example,, all the time with reference to circular cable, for ρ _min=300mm, for the radial distance with 1% prolongation is 3mm.

In some preferred embodiments, neutral region is arranged in and leaves central longitudinal axis (being neutral axis) and be no more than 0.02 ρ along the length of cable _min, and be preferably no more than 0.01 ρ _mindistance in.

Especially, observe, substantially arrange that along central longitudinal axis strain transducer may be favourable, this is because in some actual conditions, it is corresponding to the axis of symmetry of radially outer core, and/or as described below, it can with simplify cable fabrication process fit.

Except the core 2 for transferring electric power and/or control signal, cable 1 also comprises at least one earth conductor 7.In the embodiment shown in Fig. 1 a and 1b, this cable for example comprises two earth conductors 7 with the form of a branch of stranded zinc-plated or exposed copper electric wire.In particular for medium voltate application, this bundle electric wire of earth conductor can be surrounded by semiconductor layer (not shown).Earth conductor 7 with respect to strain transducer 5 radially outers arrange and twist together along cable longitudinal direction with core 2.Especially, according to conventional methods, around the spiral central longitudinal axis Z that is wrapped in cable of core 2 and earth conductor 7.

In the embodiment shown in Fig. 1 a-1b, cable 1 comprises fibre optic element 3, and this fibre optic element comprises many optical fibers for transmission of control signals, sound, video and other data-signal, for example 6 to 24 optical fibers.Wall scroll optical fiber or fiber be to being inserted in Loose-tube buffering in the module extending longitudinally 19 of being preferably made up of flexible material structure, this flexible material such as polybutylene terephthalate (PBT) or ETFE (ETFE).In the example illustrating, wrapping fibrous module is the SZ that is spirally wound around longitudinal strength member 18, and this longitudinal strength member is for example glass fibre, aramid filament or carbon fiber.Fibre optic element 3 can twist together with core 2 and earth conductor 7.Conventionally,, if cable construction allows, earth conductor and fibre optic element can be arranged in the external void that core 2 forms.

Core 2 and earth conductor 7(are if present) and/or fibre optic element 3 collectives be called the vertical structure element of cable.

The tensile strain that cable stands tends to be delivered to the strain transducer for measuring cable strain.For strain transfer, strain transducer is mechanically consistent with at least one the vertical structure element in cable, makes strain that this at least one vertical structure element stands at least in part but is delivered to significantly strain transducer.For this purpose, strain transducer 5 is embedded in strain transfer filler 6, and this strain transfer filler mechanically connects strain transducer with at least one vertical structure element of cable.Preferably, strain transfer filler by strain transducer be integrated in core in cable each mechanically connect, more preferably mechanically connect with each of the vertical structure element of circumferential arrangement.

The applicant has realized that, the prolongation that relation between the strain that the strain that strain transducer measures and cable (being at least one vertical structure element of cable) stand should make cable stand is associated clearly with the prolongation of sensor optics fiber, and therefore associated clearly with the measured value of strain.

The applicant understands, in order to ensure the univocality association between the prolongation of strain transducer and the prolongation of cable, the contact between strain transfer filler and at least one vertical structure element at least should not show significant slippage loss under strain regime.Be concerned about in most cases, between sensor and element, there is no that slippage loss means the adhesion by friction force or the bonding between them.Owing to not having significant slippage loss to cause being mechanically coupled in referred to herein as mechanical fit between two elements of substantially the same distortion between element.

In the embodiment shown in Fig. 1 a-1b, the geometrical construction of strain transfer filler 6 make when cable during in essentially no strain regime filler also contact with respect to strain transducer 5 and be arranged in the multiple vertical structure elements in radially outer position.

According to the geometrical construction of cable be integrated in the quantity of the vertical structure element in cable, the strain transfer filler 6 of Fig. 1 a and 1b has the shape of approximate trilobal.

As used herein, be described in the reference state in the fiber of strain transducer with the cable of average reference strain with " there is no the state of strain " intention, this reference state can corresponding to the state before the original cable drum carrying cable of the cable providing from manufacturer (such as, be transported to reel and anchoring spool or treatment (tender) pulley system before).But, in most of actual conditions, after reference state refers to and is arranged in movable equipment, after original cable drum transmission, and before using, the therefore cable before being exposed to relevant tensioning load.Preferably reference state can be corresponding to the state that is arranged on the cable on crane, and this crane is arranged on its maximum extension, and cable is used to the major part of its length.The applicant realize measurement show, in the state that there is no strain, in comprising that single mode 250 μ m optical fibers are as the fibre-optic cable of strain, strain varies to 0.3% from-0.2%.Due to manufacture situation difference, described cable strain can, along the length variations of cable, be preferred (because it can simplify the supervision according to cable of the present invention) although have the cable of overstrain (this overstrain is substantially longitudinally constant).

The state that there is no strain provides reference value, measures the strain of the cable in using with respect to this reference value.Along in Brillouin's method of the strain of the length distribution of cable, there is no that the state of strain can refer to multiple reference values of measuring at different parts along the length of cable in measurement.

As definition here, strain regime means to be different from any state of the state that there is no strain.Drawing stress in cable can be measured as strain deviation, with respect to the increment in the situation of the cable extension of average reference value or the decrement in the compressed situation of cable.

Strain transfer filler 6 is made up of the material with elastic property, to cable is shown elastic performance and do not had the maximum strain of Packed permanent strain (i.e. the reversibility of distortion) to react.Strain transfer filler is selected to along the cable that stands to extend and stretches suitably and work as external tension load (at least for the tensioning load corresponding to allowing maximum strain, exceed in this situation of allowing maximum strain, the permanent and irreversible distortion of cable occurs) substantially recover distortion while being removed.

Strain transfer filler 6 can, based on polymeric material, advantageously be extruded around strain transducer 5.The thermo-setting elastomer for example, in relatively large range of strain (, exceeding 1%) with elastic performance is found to be particularly suitable for cable of the present invention.Advantageously, thermo-setting elastomer is observed the surface that adheres to vertical structure element with high friction force.For example, have been noted that thermo-setting elastomer provides and semiconductor material strong bonding of core of typically surrounding some cables, shows the friction force harmless to the semiconductor outside surface of core simultaneously.The reliable strain transfer of observing the relation between the strain measuring in the strain experienced in the vertical structure element with cable predicable or that at least can derive and sensor occurs.

Advantageously, the material of strain transfer filler has tolerance to thermal treatment, during this thermal treatment may occur in cable fabrication, during curing (typically carrying out at the temperature of about 200 DEG C) such as the external jacket at cable.

Preferably, strain transfer filler comprises by vapor pressure, floods or the crosslinked thermo-setting elastomer of crosslinked with silicane system by radiation, the salt bath of electron beam.Conventionally, strain transfer filler preferably by have 0.01 and 0.7GPa between the elastic body of elastic modulus make.For example, strain transfer filler is selected from the group of following thing composition: ethylene-propylene-diene rubber (EPDM), EP rubbers (EPR), nitrile rubber (NBR).

Although thermo-setting elastomer is not because their heat-resisting sticking property and large elastic range but preferred are got rid of use thermoplastic elastomer.The example of thermoplastic elastomer comprises styrene-diene-styrene triblock copolymer; Thermoplastic polyester elastomer and Polyurethane Thermoplastic Elastomer; With thermoplastic polyolefin hydrocarbon rubbers (polyolefin blend).

In certain embodiments, strain transfer filler 6 can be electrical conductivity.

Void area 11 is filled with the polymer filler such as the compound based on EPR.External jacket 14 is for example provided by extruding.In order to increase the repellence of cable to mechanical stress, external jacket 14 preferably by preferably based on strengthen heavy thermo-setting elastomer curing polymeric material (such as, high density polyethylene (HDPE), polychlorobutadiene, polyurethane or the compound based on NBR) make.

Optionally, in order to increase the corrosion resistance of cable, arrange with for example reinforcement yarn (such as metal or PE yarn, for example by (Nomex) made) braid or the armouring 15 of the form of bifilar helix.

The applicant has realized that, for the gamut of the measurable magnitude of crossing over prolongation ensures that strain transfer occurs between the optical fiber of strain transducer and the vertical structure element of cable, advantageously, strong and substantially uniformly bonding be present in surround optical fiber and optical fiber is mechanically connected with strain transfer filler layer between.Mechanical fit between optical fiber and the strain transfer filler of this permission strain transducer.

Fig. 2 a and 2b illustrate respectively part skeleton view and the xsect of the strain transducer 5 in the cable that is integrated in Fig. 1 a and 1b according to a preferred embodiment of the invention.Strain transducer 5 comprises optical fiber 9, in the time that strain transducer is integrated in cable, this optical fiber substantially longitudinally axis Z arrange.The fiber 9 of strain transducer 5 is optical fibers, the i.e. optical fiber based on silicon dioxide, this optical fiber has the typical nominal diameter of 125 μ m, applied by primary coating, this primary coating is surrounded by secondary coating, this secondary coating typically adhesively contacts primary coating, and wherein primary coating and secondary coating form coat system.(coating) fibre-optic external diameter can be 250+/-10 μ m or 200+/-10 μ m.Also can use signal layer coating system.Preferably, optical fiber 9 is single mode optical fibres, such as meeting G.652, G.653 or G.655ITU-T(Union of International Telecommunication, ITU telecommunications portion) the transmission fiber recommended.In an embodiment, strain optical fiber is pure silicon dioxide core fibre.

Preferably, the optical fiber of strain transducer has the bending property of raising, has low bending loses.In certain embodiments, optical fiber meets G.657ITU-T recommendation.

For identifying purpose, the coloured optical fiber of tool may be favourable; In this case, preferably, use the optical fiber of the coloured secondary coating of tool.Advantageously, can select any color except white.

The applicant observes, and the optical fiber of strain transducer can tolerate and reach 1%, preferably reaches 2% repeat to extend and continue to exceed during the operation lifetime of cable the number of times of expecting the motion cycle occurring in cable.It should be noted that, the value of 1% strain be greater than cable break or permanent damages before the typical maximum extension (for example, 0.5-0.7%) that can bear.Coat system can be made up of two curing acrylate material of different UV of the diameter that reaches 250 μ m.In one embodiment, the coat system of glass fibre is as disclosed in EP1497686, and EP1497686 is observed provides the optical fiber not breaking when standing to exceed 2% repetition overtime.

In a preferred embodiment, optical fiber 9 by surround the cushion 10 of coat system by tight buffer to improve fibre-optic mechanical protection, for example, the loss of antagonism microbend.The applicant understands, cushion to the even adhesion of the optical fiber coat system of fiber (to) for ensureing that the mechanical fit between optical fiber and strain transfer filler is particular importance.

For example, cushion 10 is extruded or is applied on the fiber of 250 μ m coatings, and external diameter is increased to 600-1000 μ m, and representative value is 800-900 μ m.Preferably, cushion is made up of the material with elastic property, and this material allows the optical fiber of tight buffer to bear to reach and comprises 2% prolongation.

Advantageously, cushion is selected to and adheres to fibre-optic coat system, there is no creep, slippage or peels off.Preferably, cushion is based on having the heat proof material that is enough to withstand the heat treated thermal resistance occurring during cables manufacturing.

Preferably, cushion is made up of the acrylate polymer of radiation-curable.

For example, tight buffer is made by the curable acrylate polymer of the UV such as describing in WO2005/035461 or such as the polymeric matrix with fire-retardant filler of describing in WO2008/037291.

Adhesion-promoting layer can be arranged between coatings for optical fiber system and tight buffer layer.

The applicant observes, will be advantageously, and the optical fiber of strain transducer is protected to avoid side load, and this side load can cause microbend loss and therefore can affect the Brillouin shift measuring in fiber.In addition, as mentioned above, in the time that fiber is affected by lateral compression, strain transducer can provide not the measured value with the tensile strain of effective prolongation direct correlation of cable.For this purpose, the protection sheath 8 that is designed to improve resistibility to lateral compression can be advantageously provided into and surround the optionally optical fiber of tight buffer.

In the circular cable shown in Fig. 1 a and 1b, typically appear at radially inside direction along the lateral compression of the direction transverse to longitudinal cable direction.

The applicant observes, during cable fabrication process in the extrusion step of strain transfer filler, strain transducer can be used as tensile strength member.For this purpose, observe, importantly, during the extrusion of strain transfer filler, strain transducer material is not softening, to ensure uniform pulling force.The existence of protection sheath 8 and form the suitable selection of the material of described sheath can be advantageously for strain transducer provides tensile strength, this tensile strength is enough to improve the resistance to lateral compression and allows strain transducer in the manufacture process of cable, to serve as tensile strength member.

In order to ensure the mechanical fit between optical fiber and strain transfer filler, select the material of protection sheath to provide and the optionally fibre-optic strong and relative adhesion uniformly of buffering.

In a preferred embodiment, protection sheath 8 is made up of fiber composite, and wherein fiber can be carbon, graphite, boron or glass (non-optical) fiber.

In an embodiment, protection sheath 8 is that glass adds strength polymer (GRP), and wherein this polymkeric substance is strengthened by the glass fibre being embedded in this polymkeric substance.Observe, be parallel to the existence of reinforcing fibre that optical fiber longitudinal axis arranges and realized the advantageously relatively high anti-tensile rigidity of strain transducer, therefore prevent that lateral compression from being misread as tensile strain.Protection sheath 8 can be by pultrusion to cushion 10 and be in direct contact with it.

Optionally, the outside surface that is embedded in the protection sheath of strain transfer filler encirclement wherein by strain transducer comprises multiple grooves or otch or processed to form rough surface, so that the adhesion of increase protection sheath and strain transfer filler.Alternatively or additionally, adhesion promoting layer can optionally be arranged on protection sheath.

As mentioned above, strain transducer should have elastic response to turn back to its virgin state after cable removes tensile load, and this tensile load is associated with greatest hope cable strain.For the strain transducer with required flexibility is provided, preferably, protection sheath is made up of the material based on polymkeric substance with elastic property.Preferably, the polymkeric substance of embedding reinforcing fibre is cross-linked resin, the curable cross-linked resin of UV or thermoset cross-linked resin in particular, and this cross-linked resin provides resistance to compression pression conventionally.Cross-linked resin can be unsaturated polyester (UP), epoxy resin or vinyl esters.

Observe, in order to improve the flexibility of strain transducer, in the time being made up of the material based on polymkeric substance, the thickness of protection sheath is preferably included between 500 and 1000 μ m.For example, protection sheath is GRP layer, and the fibre-optic external diameter of buffering is increased to 1.8-2.5mm by this GRP layer.

Preferably, the fibre-optic protection sheath that surrounds sensor prevents that fiber is in manufacture process, and shrinks at the temperature using in the solidification process of some cable assemblies (such as inside and outside sheath) especially.

Selection withstands the high temperature level cross-linked resin of solidification temperature, for example high temperature of Polystal Composites GmbH gRP.

According to one side; the present invention relates to strain transducer; this strain transducer comprises optical fiber, closely surrounds the protection sheath of fibre-optic cushion and encirclement cushion; wherein cushion is made up of heat proof material; preferably made by the acrylate polymer of radiation-curable, and the compound substance that protection sheath is strengthened by fiber is made.Preferably, the compound substance that fiber is strengthened is reinforced by the reinforcing fibre being embedded in cross-linked resin.Preferably, cushion is made up of the curable acrylate polymer of UV.

Preferably, in order to make the also little compression of detection streamer of strain transducer, the optical fiber of buffering is placed in the compound substance of fiber reinforcement with the state slightly stretching of the pre-prolongation corresponding to 0.2%.

Strain transducer can detect can measure prolongation relatively on a large scale, and especially from-0.2% to 1%.Due to the prolongation up to 1% can be measured and consider that the gross fracture of cable occurs in 0.5-0.7%(and is conventionally less than 1%) prolongation under, therefore, once maximum strain tolerant is measured in a position of cable, permanent strain that just can detection streamer according to strain transducer of the present invention.

Strain is delivered to one deck from one deck at least in part, therefore ensure the reliable measurements of the cable extension in relatively large scope, and ensure at least simultaneously tensile load lower than the scope of the permanent strain of cable in the time removing tensile load elasticity return to the state that there is no strain.Due to the suitable selection of the material (this material provides the mechanical fit between different elements) of strain transducer and strain transfer filler, ensure that high efficiency strain transfer and fiber extend the known relation between cable strain.In some cases, vary to 100% to the fibre-optic strain transfer expection of strain transducer from 50% from the radially outer vertical structure element of cable.

In above preferred embodiment, strain transducer comprises optical fiber, and the layer (, tight buffer, protection sheath) that this optical fiber is had elastic property covers and is embedded in the strain transfer filler with elastic property.But; as long as can recover the prolongation in the reversible elasticity region of cable by the structure of strain transducer and strain transfer media assemblage, be selected from the group of the cushion, protection sheath and the strain transfer media assemblage that surround the fiber applying layer at least one had inelastic behaviour and there is especially plastic property.Especially, this at least one layer can be made up of plastic material, and this plastic material has the material of following ability: do not break in response to mechanical force distortion, at least until be no more than a certain threshold value of external force.The applicant understands, elastic response needs: (1) is by the material of plasticity is made substantially layer and at least one deck fit of being made up of resilient material; (2) longitudinal stiffness of the layer of being made up of plastic material is less than the longitudinal stiffness of layer at least one deck of being made up of resilient material being in contact with it of plastic material.Typically the product of the cross-sectional area of Young modulus and layer elements with the longitudinal stiffness of N tolerance.Like this, the layer of being made by the material of plasticity substantially during cable extension, adhere to by friction force along it or contact resilient material thereon stretch and be withdrawn into by resilient material its original position (as long as enough holding forces be present in this two-layer between).

For example, the protection sheath of strain transducer is the thermoplastic polymer with the fiber reinforcement of the Young modulus of 72,400MPa, and strain transfer filler is the thermo-setting elastomer with the Young modulus of 671MPa.The cross-sectional area of protection sheath is 3.4mm ²and the cross-sectional area of strain transfer filler is 75mm ², for protection sheath provides the longitudinal stiffness of 250kN and provides the longitudinal stiffness of 50kN for strain transfer filler.The thermoplastic polymer of strengthening as fruit fiber adheres to well strain transfer filler and adheres to the layer (such as cushion) being positioned at below, and thermoplastic polymer is along with strain transfer filler carries out, even if its cross-sectional area is much smaller.To notice, and suppose and meet above-mentioned condition (1) and (2), and the layer wherein with elastic property is the cushion that protected sheath surrounds, if strain transfer filler is made up of thermoplastic polymer, this will be also correct.

In an embodiment, under the hypothesis of (1) and (2) that satisfies condition, strain transfer filler is selected from the group of following thing composition: have 1 polyester to 5GPa Young modulus, there are 2 polyamide to 4GPa Young modulus, there is 0.003 Polyvinylchloride (PVC) to 0.01GPa Young modulus, there is 0.1 Low Density Polyethylene to 0.3GPa Young modulus, and there is 0.4 high density polyethylene to 1.2GPa Young modulus.Preferably, use crosslinked polymeric materials.

According to another embodiment, for resistance and the tensile strength to side load is provided for strain transducer, the protection sheath of strain transducer can be to surround the optionally metal tube (not shown embodiment) of the fibre-optic cushion of buffering.In this case, metal tube comprises gel or gel-like material, this gel or gel-like material optionally under pressure, can provide metal tube and the optical fiber that wherein comprises between the mechanical fit of seeking.In a preferred embodiment, metal tube is formed from steel.

Made by the material with plastic property for one in the group of cushion, protection sheath and the strain transfer media assemblage of the fiber preferably, only being applied by encirclement.

Although in some preferred embodiments; strain transducer comprises cushion to improve intensity and the elasticity of strain transducer; in structure shown in Fig. 2 a and 2b; but be to be understood that; strain transducer can comprise the optical fiber that is coated with coat system, and this coat system is by protecting sheath directly to surround.

Cable 1 preferably includes temperature sensor, and this temperature sensor comprises the optical fiber 24 of the internal temperature for measuring cable 1.The optical fiber 24 of temperature sensor is in dredging absorbing structure.Especially, in the embodiment illustrating in the drawings, optical fiber 24 is loosely placed in the module 19 of longitudinal encirclement fiber, and this module 19 is included in fibre optic element 3.The excessive optical fiber length that module 19 extending longitudinally comprises per unit length lightpipe optics fiber 24.Excess fibre length (EFL) is limited by following relation:

$\mathrm{EFL}=\frac{L_f-L_t}{L_t}\·100-\left(1\right)$

Its 1L _ffibre-optic length and L _tthe length of holding the pipe of fiber.Select excess length to make optical fiber be applied to for example, under the maximum strain of cable (, 1%) maintenance loose (there is no strain).

The optical fiber 24 of temperature sensor is preferably single mode fibre and passes through to use Brillouin backscattering commercial measurement temperature.But, can envision multimode optical fiber for temperature detection.In latter instance, can be by using the known technology based on Raman scattering to carry out temperature survey.Preferably, optical fiber 24 is wound around spirally with respect to the central longitudinal axis extending along cable.For example, optical fiber 24 coils longitudinal member.In the case of comprising the fibre optic element cable of (this fibre optic element comprises more than an optical fiber), two fibers can be along the longitudinal direction each other spiral fashion be wound around, an optical fiber as temperature sensor in these two fibers.Only expanded by heating impact and can be used for temperature monitoring of the optical fiber 24 that there is no a mechanical stress.When by the strain of Brillouin backscattering commercial measurement, the strained and influence of temperature change of strain optical fiber.By optical fiber 24 being connected optically with strain optical fiber and by measuring the temperature variation in optical fiber 24, can deducting temperature contribution.

Although preferably, when the mechanical attachment between strain transducer and vertical structure element also appears in cable in the time there is no the state of strain, but in order to improve the resolution of detection sensitivity and strain measurement, mechanical attachment between strain transducer and vertical structure element, and particularly mechanical fit, can be only subject to tensile load and becomes while contacting with strain transfer filler occurring when at least one of vertical structure element.For example, in the time that standing the tensile load corresponding at least 0.1% prolongation, vertical structure element there is mechanical attachment.

Fig. 3 is the cut-open view of cable according to other embodiments of the present invention.Identical Reference numeral is for identifying the similar parts that have to the same or similar function of element of Fig. 1 b.Although Fig. 1 a and the embodiment in 1b are included in the strain transfer filler of the vertical structure element that also contacts cable in the situation that there is no tensile load, but in embodiment shown in Figure 3, before installing or using in movable equipment, when the state of cable in there is no strain (for example, the virgin state of cable) time, strain transfer filler does not contact the surface of (not being at least fully) vertical structure element.Especially, cable 30 comprises the strain transducer 5 being surrounded by strain transfer filler 25, and this strain transfer filler is preferably directly extruded on strain transducer, for example, with reference to figure 2a and 2b, is directly expressed on the outside surface of protection sheath 8.Strain transfer filler 25 can have circular cross section.For example, protection sheath 25 has 2 to 7mm thickness.Strain transfer filler 25 and radially outer vertical structure element (are core 2 and earth conductor 7 and fibre optic element 3, void space 26 if present) can besieged vertical structure element the same material (for example, the compound based on EPR) of polymer filler 27 fill.

Because its size, in the void space 26 of the strain transducer 5 being cushioned by strain transfer filler 25 between strain transfer filler 26 and cable vertical structure element, relative to freely moving, the mobility of strain transducer also depends on the viscosity of the material of filling void space.In the situation that applying tension force, vertical structure element tends to radially inwardly compress, and is therefore reduced to the radial distance of strain transducer along the longitudinal axis of its layout.When the value of the tension force standing when cable is greater than a certain threshold value, vertical structure element is by inside contacting of pressure and formation and strain transfer filler 25 radially.On the contrary, when the overtime in any lengthwise position of the length of cable of cable lower than that threshold value in the situation that, the optical fiber of strain transducer 5 is due to the clamping of the relative mistake of the vertical structure element of cable and necessarily to postpone to follow cable moving.Preferably, the threshold value of tension force is 0.1%.

The material character of strain transfer filler 25 is those character above with reference to Fig. 1 and 1b description.

Fig. 4 is the cut-open view of cable according to other embodiments of the present invention.Identical Reference numeral is for identifying the similar parts that have to the same or similar function of element of Fig. 1 a and 1b.Cable 40 comprise with respect to strain transducer 5 radially outers four vertical structure elements arranging, i.e. three electric power cores 43 and earth conductor 44, these four vertical structure elements can have the structure of describing with reference to figure 2a and 2b.Electric power core 43 and earth conductor 44 comprise be respectively insulated that polymeric layer 46 surrounds for example with the conductor 45 of the form of a branch of stranded zinc-plated or exposed copper electric wire.Space between strain transfer filler 47 embedding strain transducers 5 and filling strain transducer and vertical structure element.The character of strain transfer filler 47 and geometric configuration make mechanical attachment in the state that there is no strain of cable (especially mechanical fit), be also present in vertical structure element 43 and 44 and strain transducer 5 between.

Cable 40 can be such as the 1kV power cable for vertically batching application.In embodiment shown in Figure 4, temperature sensor 48 is integrated in the region of vertical structure element inner radial, and especially in strain transfer filler 47.Temperature sensor 48 comprises optical fiber 49, and this optical fiber is preferably single mode optical fibre, is loosely arranged in module extending longitudinally 41, and this module is preferably made up of ETFE or PBT.The external diameter of module 41 is for example 2mm.

Alternatively, temperature sensor can be integrated in the neighboring area of cable cross-section of vertical structure element radially outer.

Fig. 5 is the cut-open view of cable according to other embodiments of the present invention.The cable illustrating can be for example for batching the low-voltage control cables of application.Cable 50 comprises the multiple vertical structure elements that are arranged in multiple concentric layers, and the plurality of concentric layer is wound on around the center part 51 of the strain transfer filler that serves as strain transducer 5.The vertical structure tray of elements of each concentric layer is around center part 51 and comprise and control core 53 and be arranged in a pair of fibre optic element 54 in most external concentric layer.Each is controlled core 53 and comprises and be insulated the fine rule copper conductor 59 that polymeric layer 58 surrounds.Article two, fibre optic element 54 is the form of module 52 extending longitudinally, and it is three optical fibers in the drawings that this module comprises at least one optical fiber 57(being loosely arranged in this module).The optical fiber of arbitrary of fibre optic element 54 can be used as temperature sensor.Polymkeric substance internal jacket 55 surrounds the concentric layer of vertical structure element.The external jacket 36 with the stiffener (such as PE yarn braid 35) of embedding surrounds internal jacket 55 and surrounds cable.

Strain transducer 5 is arranged in the neutral region of the cable that surrounds central longitudinal axis.For example, neutral region is the radial zone extending along central longitudinal axis, for the ρ with 120mm _mincable, this radial zone has the radius of 3mm.

In with reference to the embodiment shown in figure 1,3,4 and 5, under strain regime, the vertical structure element of cable connects with strain transfer filler direct mechanical,, between vertical structure element and strain transfer filler, has mechanical fit that is.Consequent cable construction makes the strain standing such as the vertical structure element of core or earth conductor can effectively and rapidly be delivered to strain transducer.The rapid reaction of strain variation is allowed to the detection of the dynamic tension for example occurring in the flip-flop of winding direction or the motion of the load/unload of movable equipment.

Should be appreciated that when originate from the part (such as cable internal jacket or external jacket) of the cable directly not contacting with strain transfer filler according to the cable of instruction of the present invention, also allow to carry out the detection of strain.

In addition, the present invention includes cable, this cable comprises multiple vertical structure elements and be embedded in the strain transducer in strain transfer filler, and wherein at least one in vertical structure element connects with strain transfer filler direct mechanical.

If the tension force of substantial constant is applied to a vertical structure element of cable during given interval, described power is determined friction force and the strain flexible, that be integrated in all vertical structure elements in cable depended between the intermediary element/layer of the vertical structure element mechanical attachment of strain, the strain of the element for example directly contacting with the vertical structure element of strain, or cross over and carry out mechanical attachment such as the material (such as polymer jacket) that other element is separated with the element of strain.Friction force larger (also depending on the value of tension force) between the larger and element of contact area needs the longitudinal length part of the cable with homogeneous strain shorter between vertical structure element.For the heavy cable for movable equipment, having the necessary longitudinal length part of the strain being distributed in whole piece cable cross-section is approximately five cable sizes, is therefore typically no more than 20-40cm.The strain value working in the different piece of xsect depends on the elastic property of constituent material.

Such as in dynamic strain measurement, a vertical structure element that is applied to cable at the tension force that can change in time, consider the strong adhesion between friction force, the layer between element, and therefore form the suitable selection of the material of this layer, it is important that the construction of cable becomes.

Fig. 6 illustrates the schematic sectional view such as the three-phase flat cable 60 of the application for well pump system, and this three-phase flat cable comprises two external core 61 and 63 and central cores 62.This core is arranged to substantially parallel to each other and adjacent, arranges between two parties along the common axis line 69a that is parallel to the directions X that becomes horizontal with longitudinal cable axis.Axis 69a is the medium line of the cable cross-section in plane (X, Y).Optical fiber strain transducer 5 is arranged between (being external core 61 in this situation) of central core 62 and external core.Strain transducer 5 can have the structure with reference to figure 2a and 2b description.Strain transducer 5 is surrounded by strain transfer filler 66, and this strain transfer filler can have round-shaped and adhere to the outside surface of strain transducer.The radial thickness of strain transfer filler 66 is selected to the side void space depending between side core 61 and central core 62 and to provides necessary mechanical resistance.Preferably, when cable is in the time there is no the state of strain, the outside surface of strain transfer filler and adjacent core 61 and 62 is by mechanical attachment and especially mechanical fit.

The bending neutral axis of cable 60 is medial axis 69a, and this medial axis is the axis of symmetry along the cable cross-section of Y-axis line.Strain transducer 5 is arranged in the bending neutral region of the thickness d limiting between two plane 69b, and these two plane 69b are parallel to medium line 69a and are d/2 along the distance that Y-axis line leaves 69a.For the ρ with 500mm _minthe flat cable of representative value, thickness d can vary to 10mm from 5.

Flat cable 60 also comprises outside armouring 68, and this outside armouring is arranged in respect in the external position of core and longitudinally surround them.Outside armouring 68 has and is parallel to two of X-axis line two relative side direction side 68b of smooth side 68a and two external core 61 of encirclement and a part of 63 substantially.Outside armouring 68 is preferably the band armouring of steel or stainless steel or copper and mickel alloy.

Cable 60 has multiple void spaces 65, and the plurality of void space is by the space boundary between core and outside armouring 68.Strength member 67 is arranged in void space 65 in two common planes that are parallel to X-axis line.Strength member 67 has circular cross section and can be made up of the polymkeric substance of steel, glass or reinforcement.

Free space between core and strength member is filled with internal jacket 64, and this internal jacket is for example made up of the polymerizable compound with mineral filler, is preferably directly extruded on the vertical structure element of flat cable.

By use Brillouin backscattering technology (such as, Brillouin light time-domain reflectomer (BOTDR), Brillouin light class hour domain analysis instrument (BOTDA) and Brillouin's optics frequency domain reflectometer (BOFDR)), can monitor that cable according to the present invention is to determine the strain along cable distribution.According to common known measuring technique, the first optical signalling (detector) being produced by the first laser enters the fibre-optic first end of the strain transducer being integrated in cable, and the second optical signalling (pump) meanwhile, producing by the second laser or by the first identical laser enters the relative the second end of fibre-optic and first end of strain transducer.The first optical signalling operates continuously, be continuous wave (CW) signal, and the second optical signalling is pulse.Measure from the backscattered optical signalling detected circuit of returning of fibre-optic first end.Difference between the light frequency of CW optical signalling is greater than a certain amount of than the difference of pulse optical signalling, this certain connection equals amount of the Brillouin shift at some the some places in fiber, pulse signal by Brillouin interact be exaggerated and CW signal through suffering a loss.Brillouin shift is strain and temperature sensitive.Brillouin backscattering technology has advantages of that, for distribution sensing technology, therefore this allow along the real time monitoring of the actual strain profile of the length of cable.

Pass through sample devices, Brillouin scattering can be used for measuring the temperature of fibre-optic length and the variation of strain along strain transducer simultaneously, and this sample devices shines upon Brillouin spectrum to obtain temperature and strain information by the frequency displacement and the matching Brillouin peak that scan two lasing light emitters.By business type BOTDR equipment, such as by the business-like Foresigh of OZ Optics Ltd ^tMsensor, can carry out this analysis.In this application, the temperature sensor being arranged in the position separating with strain transducer in cable is unnecessary for temperature sensing.

In some preferred embodiments, by the strain contribution separation temperature contribution from the optical signalling of measuring, and by by the second optical fiber of loose absorbing structure for temperature survey, carry out the supervision of strain and temperature, as what describe in some of the previous embodiment of cable.

Fig. 7 is the schematic block diagrams that the principle of operation of surveillance is shown, this surveillance is used such as the backscatter technique based on Brillouin of BOTDR and measured strain and the temperature variation in the length of cable.Sample devices 70 is for introducing optical signalling and analyzing the backscattered optical signalling receiving from cable at cable 73.For example, sample devices can be by the business-like DITEST-DSM system of Omnisens SA.Cable comprises strain transducer, and this strain transducer comprises only schematically illustrated strain and temperature fiber in the optical fiber 71 that extends along cable longitudinal direction Z and temperature (sensor) optical fiber 72(figure).The strain transducer that comprises strain optical fiber 71 is mechanically connected at least one vertical structure element of cable 73 to allow strain to be delivered to strain transducer from this at least one vertical structure element, and is integrated in cable for the optical fiber 72 of temperature sensing with the structure loosening.Cable 73, and the layout of optical fiber 71 and 72 in cable particularly, can have the structure of any structure of those structures as described in previous embodiment.Strain optical fiber 71 is arranged in the longitudinal neutral bending area of cable and has mechanical fit with at least one vertical structure element of cable, and temperature optical fiber 72 is not arranged with the absorbing structure that loosens to be not applied to the strain of cable and affects.Sample devices 70 is launched pumping optical signalling to the optical cable part 74 of close end that is connected to strain optical fiber 71 from the first output 78.Meanwhile, detector optical signalling is transmitted into the optical cable part 75 of the close end that is connected to temperature optical fiber 72 from the second light output 79.For the term " closely " of fiber end and " far " with respect to sample devices, or at least with respect to being connected with the optics of sample devices.But this term is only intended to indicate relative position and/or for facilitating the description of accompanying drawing, but they are not interpreted as having absolute sense.The cable section 74 and 75 of measuring equipment 70 can form by conventional equipment to the impermanent connection between corresponding optical fiber 71 and 72, for example, by optical conenctor 77.In strain and temperature optical fiber 71 and 72 at least one, and two fibers preferably, have and extend beyond the close end of cable 73 and the length of distal portion.In the fibre-optic end that approaches sample devices 70, this has simplified the connection to this equipment.Fibre-optic with the close end relative distal portion outstanding from cable is connected to each other to produce fibrous ring, and this fibrous ring has two I/O ends in an only end (, close end) of cable.In remote end part, according to conventional methods in contact maker 76 by welding, two fibers can link together.

Brillouin backscattered light signal leaves temperature sensor fiber 72, enters sample devices 70 and can be processed so that definite strain along cable and temperature variation.Comprise the fibrous ring of strain optical fiber 71 and temperature fiber 72 by consideration, the strain of measurement and temperature are determined bit position along fibrous ring (and therefore in each of two sensing fibers) and can be propagated downwards and transit time of returning by fibrous ring be determined by pulse.

Optical fiber ring can be by using known technology (such as by using OTDR technology) be calibrated, to know that the optics in position and/or the fibrous ring of connector connects, and therefore definite temperature and position and the length of strain optical fiber in fibrous ring.

Strained and the influence of temperature change of strain optical fiber 71, and be configured in the only temperature influence of temperature optical fiber 72 in the construction of cable to loosen.Contribute by deducting along the temperature of the fibrous ring part corresponding to being integrated in the optical fiber 72 in cable, can determine the contribution to Brillouin shift only being caused by strain.

In an embodiment, mirror can be arranged in the fibre-optic remote end part of temperature with respect to sample devices, and pump and detector optical signalling are launched in the fibre-optic close end of temperature.This scheme (not shown) does not need the fibrous ring between strain and temperature optical fiber for measuring.

Strain in strain optical fiber and comprise that relevant between the strain in the fibre-optic cable of strain can be used strain calibrating installation to determine by fabricator, this strain calibrating installation can be applied to cable by the extend longitudinally of known quantity.By Brillouin scattering technology, according in rest position and the cable of prolongation that suffers known quantity, analyze optical fiber to determine the prolongation in fiber.For example, when cable suffers uniformly and " static state " overtime, 0.75% (Δ L/L) _fibrecorresponding to 1% (Δ L/L) _cable, represent that 75% strain is delivered to fiber from cable.

The applicant observes, and the cost (if needing especially wide region high-sensitivity measurement) of Brillouin's sample devices is relatively high, and therefore will be advantageously, provides the surveillance of many cables to reduce total cost.

The applicant also has been noted that the real time monitoring of heavy cable will allow record to cause the dynamic event at elastic strain peak, and this dynamic event can be by fatigue breakdown cable.

Fig. 8 is the schematic diagram of the surveillance of many heavy cables in the region (such as the container wharf at harbour) for goods movement.Container wharf is the port installations that conventionally cover large region, is stored to be loaded onto ship or collect from harbour across these port installations, container (not shown).The selection area that multiple heavy duty cranes 82 are crossed over harbour moves to lift and shift container, is supplied electric power and is controlled from electric power transfer station 81 simultaneously.Heavy duty crane 82 can be the gantry being fixed on a tracking 90a and 90b, it is upper that this tracking is arranged on harbour region, harbour (this region, harbour represents with hatched area 91 in the drawings) below, and wherein quay crane is for the operation of loading and unloading ship.Container (not shown), with in the stacking space between in-orbit of number row, can be lifted and move back and forth by gantry there, and this gantry flatly moves back and forth along double-head arrow 92 indicated directions.Fig. 9 is the side view of multiple gantries that for example the C-C line along Fig. 8 obtains.The supporting construction of gantry 82 comprises the bridgeware (invisible in Fig. 9) with two elevated rail 93a and 93b, and winch truck 83 moves perpendicular to the motion of crane on this bridgeware.According to conventional design, winch truck 83 has the capstan system (not shown) for lifting container.

End stops 88 can arrange that two ends are in-orbit to prevent that crane movable from exceeding rail end.

Each gantry 82 provides electric power by corresponding cable 86, and this cable can be conventional power cable, and electric power transfer station 81 is connected to crane feeding unit 89.Heavy cable 85 is connected to crane feeding unit 89 to obtain electric power and provide electric power for the several functions (it moves, locates, monitors etc.) of crane 82 from the crane feeding unit being carried by corresponding cable 86.In addition, heavy cable receives control/datagram number and/or optical signalling.Although crane feeding unit is shown as near being placed near the rail end at electric power transfer station, other position of crane feeding unit is possible, such as the centre position place on the side of the rail of the length with respect to rail.

Heavy cable 85 spool 84 on the cross side of crane structure that is fastened.Cables reel 84 can be motorized to allow spool to rotate along both direction.Cable can be from guiding device 96(Fig. 9 to the guiding of crane feeding unit) provide, in the embodiment of this figure, this guiding device comprises two deflection guide reels of laterally relatively arranging.An end of each cable 85 is fixed in corresponding crane power supply unit 89 and relative end is typically fixed on cables reel 84 places at the center (being called backbone) of cable reel.During the moving horizontally rapidly of crane, when in the time that the discontinuous and common unexpected winding of the cable of spool and unwinding stage occur, heavy cable 85 is restrained two ends subsequently.Conventionally, the acceleration of crane and deceleration synchronously do not occur with winding or the unwinding of cable, therefore in the prolongation of cable, apply the peak value of repetition.

In an embodiment, heavy cable has the structure with reference to the type of figure 1a and 1b description.In another embodiment, heavy cable has with reference to figure 1a-1b, 3,4 and 5 structures any of describing.

Refer again to Fig. 8 and 9, each heavy cable 85 comprises strain transducer and temperature sensor.The mechanical attachment that comprises strain transducer arrives the optical fiber of at least one vertical structure element of cable, especially with the matched optical fiber of at least one vertical structure element machinery of cable, and the temperature sensor structure that comprises loosening is integrated in the optical fiber in cable.At least the optical fiber of strain transducer is single mode optical fibre, and preferably, the optical fiber of temperature sensor is also single mode optical fibre.Preferably, strain and temperature optical fiber are carrier class optical fibers.

Each electric power being transported in the power supply cable 86 of heavy cable 85 comprises integrated fibre optic element, and this integrated fibre optic element comprises preferably with the absorbing structure that loosens along at least two optical fibers supplying with cable arrangement.Each fibre-optic end optics of supplying with in cable 86 is connected to Brillouin's sample devices (not shown in Fig. 8 and 9), and relative end optics is connected to strain and the fibre-optic corresponding end of temperature that heavy cable 84 comprises.Optics connects and can in power supply unit, occur by conventional equipment.Therefore the optical signalling that, makes heavy cable 85 receive electric power and to analyze for Brillouin from corresponding supply cable 86.Brillouin's sample devices can be accommodated in electric power transfer station 81.In Fig. 8 and 9, for the purpose of clear, supply with cable 86 and be shown as the side of resting on the ground.Should be appreciated that supplying with cable can reach crane power supply unit simultaneously in subsurface extension (being described by dotted line in Fig. 9).

Figure 10 is schematic diagram, illustrate according to embodiment for controlling the principle of operation that is arranged on the strain of many heavy cables on movable equipment and is preferably used for the surveillance of controlling its temperature.Supply with cable 103,105,107 and 109 for many and correspondingly comprise respectively the first and second supply optical fiber 118a and 118b, 119a and 119b, 120a and 120b and 121a and 121b.Supply with cable 103,105,107 and 109 supply electric power, and preferably supply control signal is to corresponding heavy cable 104,106,108 and 110, each heavy cable comprises strain transducer optical fiber 112a and temperature sensor optical fiber 112b.The first supply optical fiber 118a, 119a, 120a and 121a optics are connected to the strain optical fiber 112a of corresponding heavy cable 104,106,108 and 110.The second supply optical fiber 118b, 119b, 120b and 121b optics are connected to the temperature optical fiber 112b of corresponding heavy cable 104,106,108 and 110.Supplying with and the strain of heavy cable and the fibre-optic optics of temperature of the supply optical fiber of cable is connected and can be implemented by welding.Being positioned at the strain of each heavy cable and the end of temperature optical fiber 112a and 112b at a distance with respect to corresponding supply cable is connected to each other (being represented by the tie point installing, for example contact maker 113) to form the fibrous ring of crossing over heavy cable and supplying with cable.In the embodiment shown in Fig. 8 and 9, the end of the fibre-optic distal site of strain and temperature heavy cable of (for example, in the backbone of spool) in the spool that is bonded on crane.

Brillouin's sample devices 100 sends the first optical signalling (pump) and sends the second optical signalling (detector) from I/O optical port 102 from I/O optical port 101.Signal is launched into corresponding the first and second optical fiber parts 111 and 114 from I/O optical port 101 and 102.The first optical fiber part 111 optics are connected to the first supply optical fiber 118a of the supply cable 103 that receives pump signal, and the second optical fiber part 114 optics are connected to the second supply optical fiber 121b of the last supply cable 109 of pick-up probe signal.First the second supply fiber 118b optics of supplying with cable 103 is connected to first of the second supply cable 104 and supplies with fiber 119a; The second supply fiber 119b optics of the second supply cable 104 is connected to first of the 3rd supply cable 105 and supplies with fiber 120a, and the 3rd the second supply fiber 120b optics of supplying with cable 105 is connected to the first supply fiber 121a of the second supply cable 107.This produces fibrous ring, this fibrous ring have as the light I/O of opening near first end (close end) of supplying with first of cable 103 and supply with end and the 4th of fiber 118a and supply with second of cable 109 and supply with fiber 121b.With reference to accompanying drawing, term " closely " and " far " can be understood to reference sample equipment, or at least with reference to being connected with the optics of sample devices.But this term is only intended to indicate relative position and/or describes for convenient, but they are not interpreted as having absolute sense.Article two, a fibre-optic end of the optical fiber end of different supply cables or supply cable connects and can be implemented by conventional coupling arrangement with the light that optics is connected to the pars fibrosa of sample devices, and this routine coupling arrangement is not illustrated in the drawings.

The quantity that is connected to the heavy cable of the Brillouin's sample devices shown in Figure 10 is 4.But, should be appreciated that with Brillouin's instrument dynamically compared with, depend on that light loss, welding loss, mechanical engagement that fiber decay and fibre length cause lose, this quantity can be different.For example, the heavy cable of 10 of reaching being arranged in corresponding crane can be measured in single fibrous ring.

Supply with optical fiber and be preferably carrier class single mode optical fibre.

The first and second optical signallings are the backpropagation optical signallings with suitable amplitude and frequency for generation of Brillouin backscattering signal, and this Brillouin backscattering signal is sampled equipment 100 and analyzes.Supply with in cable and form the fibre length of the fiber in the heavy cable of fibrous ring by understanding (for example, after the calibration of the Wiring structure in ring), strain variation can be associated with to the position along fibrous ring, and therefore monitor the strain that is applied to optics and is connected to each heavy cable of sample devices.

According to an aspect of the present invention, be used for monitoring that the surveillance of many cables (and in particular for monitoring many heavy cables) comprising: for measuring the sample devices of spectrum change of Brillouin scattering, this sample devices comprises the first and second smooth input/output end ports, and the first input/output end port tends to send the first optical signalling and the second input/output end port tends to send the second optical signalling, with many heavy cables, these many heavy cables comprise first and last heavy cable, each cable in these many cables comprises strain transducer and temperature sensor, this strain transducer comprises strain optical fiber, this temperature sensor comprises temperature optical fiber, this strain and temperature sensor are extending longitudinally along corresponding cable, this strain optical fiber and temperature optical fiber have close end and distal portion, this close end is arranged in the close end of corresponding cable, wherein: the strain optical fiber of each heavy cable and the fibre-optic distal portion of temperature each other optics are connected, the fibre-optic close end of strain of the first heavy cable and the first I/O optical communication of sample devices and the last temperature optical fiber of cable and the second input/output end port optical communication of sample devices, and the fibre-optic close end of the temperature of the first heavy cable is connected with the fibre-optic close end optics of strain of last heavy cable, to form optical fiber ring, in this optical fiber ring, the first and second input/output end port optical communications of the strain optical fiber of each heavy cable of many heavy cables and temperature optical fiber and sample devices, and the first and second optical signallings enter optical fiber ring in opposite direction.

The applicant observes, and commercially available Brillouin's sample devices can be measured the fibre-optic strain and the temperature that reach 20km.When crane be dispersed on large region and along the horizontal direction of the direct of travel perpendicular to crane spaced apart sizable apart from time, it may not be high efficiency especially that greatly isolated crane is connected to the identical electric power transfer station shell that holds sample devices.In addition, will be advantageously, use the Wiring structure from electric power transfer station to crane being typically pre-existing in.

Figure 11 illustrates the surveillance of many heavy cables in the region for goods movement (such as the container wharf at harbour) according to other embodiments of the present invention.Identical Reference numeral is for identifying the similar parts that have to the same or similar function of element of Fig. 8.Electric power and control signal are supplied to first group of crane 130 in electric power transfer station 125, and electric power and control signal are supplied to second group of crane 131 in electric power transfer station 128.Any of electric power transfer station held Brillouin's sample devices (not shown), and this sample devices is connected in the supply cable at other electric power transfer station by optical cable 129 optics, and this optical cable comprises two optical fibers that are preferably single mode optical fibre.The quantity of the crane in each group is exemplary completely, although typically from 3 to 6 variations of this quantity.

The possible optical configuration of the surveillance of Figure 11 is illustrated in the schematic diagram of Figure 12.Supply with cable 145,149,150 and 152 for first group and comprise respectively the first and second supply optical fibers, this first and second supplies optical fiber is connected to corresponding strain and the temperature optical fiber of corresponding heavy cable 146,147,148 and 151 by known method (such as by optical conenctor 167) optics.Supply with cable for first group and receive electric power from the first electric power transfer station.Supply with cable 158,159 and 160 for second group and comprise respectively the first and second supply optical fibers, this first and second supplies optical fiber optics is connected to corresponding strain optical fiber and the temperature optical fiber of corresponding heavy cable 155,156 and 157.Supply with cable for second group and receive electric power from the second electric power transfer station (not shown Figure 12).Two light input/output end ports, 163 and 164 optics of Brillouin's sample devices 143 are connected to the corresponding input port 165 and 166 of photoswitch 140.Input/output end port 163 sends the first optical signalling (pump), and input/output end port 164 sends the second optical signalling (detector).With reference to Figure 11, sample devices 143 and photoswitch 140 can for example be accommodated in the first electric power transfer station 125.Photoswitch 140 tends to the first optical signalling receiving to separate and be directed to two input/output end ports 141 and 161, and the second optical signalling receiving is separated and be directed to two input/output end ports 142 and 162.Photoswitch 140 can be general type, for example single mode fibre 1x2 or 1x4 or 1x8 photoswitch.

The strain of each heavy cable of first group and the fibre-optic distal portion of temperature each other optics are connected (for example, by connector 113) to form the first fibrous ring, and this first fibrous ring has as first opens that first of end supplies with that first of cable 145 is supplied with the end of fiber and as the second end of opening the 4th of end and supply with second of cable 152 and supply with fiber.The input/output end port 141 of photoswitch is connected to the close end of the first fiber optics of the first supply cable 145 by pars fibrosa 111 optics, and the input/output end port 142 of photoswitch is connected to the close end of the second fiber optics of the 4th (finally) supply cable 152 by pars fibrosa 114 optics.

The first optical signalling (pump) sending from output port 141 is launched into the first supply fiber of supplying with cable 145, and the second optical signalling (detector) is launched in the second optical fiber of supplying with cable 152.The first optical signalling enters first group first supplying with one of cable 145 and supply with fiber, advances along fibrous ring, and it is propagated along the supply of first group and all fibres of heavy cable, and from the fiber of last supply cable 152 out.The second optical signalling sending from input/output end port 142, with respect to the first optical signalling backpropagation, is advanced along fibrous ring in opposite direction.The the second fibre-optic Brillouin backscattering signal that leaves supply cable 152 enters photoswitch 140 and is analyzed by sample devices 143.

Similarly, the distal portion of the heavy cable 155,156 of second group and each of 157 each other optics is connected to form the second fibrous ring, this second fibrous ring has two optical tip of opening, and supplies with the first optical fiber of cable 158 and the second optical fiber of supply cable 160.In this fibrous ring, first the second fibre-optic close end of supplying with cable 158 is connected with second the first optical fiber optics of supplying with cable 159, and similarly, second the second fibre-optic close end of supplying with cable 159 is connected with the 3rd the first optical fiber optics of supplying with cable 160.The input/output end port 161 of photoswitch 140 is connected to 162 optics corresponding the first and second connection optical fibers that are connected optical cable 144, and this optical cable has the first end of close photoswitch 140 and is positioned at the second end at a distance with respect to photoswitch.In the distal portion relative with close end of optical cable 144, first and second connect optical fiber optics is connected to the first optical fiber of supplying with cable 158 and the second optical fiber of supplying with cable 160.Like this, second group of heavy cable receives two sampling optical signallings from connecting optical cable 144, and the optical signalling wherein sending from equipment 143 enters photoswitch 140 and guided to and connect optical cable 144 by photoswitch 140.The Brillouin backscattering signal producing in the heavy cable of second group is fed back to and connects in optical cable 144 and guided to input/output end port 165 and 166 by photoswitch 140, therefore enters sample devices 143.

Advantageously allow further to reduce the cost of surveillance with reference to the embodiment of Figure 11 and 12 descriptions.

Although in the aforementioned embodiment, supply cable is described as to be provided with and comprises at least two fibre-optic fiber optic components, but because this may represent the situation of the conventional electric power cable that can transport light data and/or control signal, therefore the present invention includes supply wiring system, this supply wiring system comprises electric power supply cable and optical cable, and this optical cable comprises at least two optical fibers.In that case, optical cable can supply with at electric power that extend on cable side and optics is connected to strain and the temperature optical fiber of heavy cable.

The present invention can be applied to surveillance, and in this surveillance, the direct optics of sample devices is connected to many heavy cables, and these many heavy cables are provided with optical fiber strain transducer, and are preferably provided with optical fiber temperature sensor.In other words, conventionally, the fibrous ring of surveillance does not need to comprise supplies with cable as the middle electric power/control power supply component for heavy cable, does not especially cross over the distribution of large region (such as port container terminal) at the many cables that will be monitored.

Claims (12)

1. one kind at least measuring the distortion supervision method of tensile strain of at least one cable, said method comprising the steps of:

At least one cable is provided; described at least one cable comprises: strain transducer (5); described strain transducer is extending longitudinally and comprise the strain optical fiber (9) being arranged in bending neutral region along described cable, and described bending neutral region surrounds and comprise the neutral longitudinal axis (Z of bending of described cable; 69a); At least two vertical structure elements (2,7,3; 43,44; 53,54; 61,62,63), at least one in described at least two vertical structure elements is to comprise electric conductor (12; 45; 59) core (2; 43; 53), wherein said strain transducer at least in strain regime with described at least two vertical structure elements at least one mechanical attachment;

The first optical signalling is introduced to described strain optical fiber;

Detect the Brillouin scattering sending from described strain optical fiber; With

Analyze the spectrum change in described scattered light, at least measure the tensile strain of described at least one cable.

2. method according to claim 1, wherein, described at least one cable also comprises the temperature optical fiber (24 for temperature sensing; 49; 57), described temperature optical fiber extends and is encapsulated in module extending longitudinally (19 with the structure loosening along the length of described cable; 41; 52) in, and described temperature optical fiber is connected to described strain optical fiber by optics, and described method is further comprising the steps of: along the direction of propagation contrary with respect to described the first optical signalling, the second optical signalling is introduced to described temperature optical fiber.

3. at least measuring the distortion surveillance of tensile strain at least one cable, described distortion surveillance comprises:

Cable, described cable comprises: strain transducer, described strain transducer is extending longitudinally and comprise strain optical fiber along described cable, described strain optical fiber has the close end and the distal portion that are arranged in bending neutral region, and described bending neutral region surrounds and comprise the neutral longitudinal axis of bending of described cable; At least two vertical structure elements, at least one in described at least two vertical structure elements is the core that comprises electric conductor, wherein said strain transducer at least in strain regime with described at least two vertical structure elements at least one mechanical attachment; With

Sample devices, described sample devices is used for the spectrum change of the Brillouin scattering of measuring described strain optical fiber, and described sample devices connects with the fibre-optic at least described close end optics of described strain, to light is introduced to described strain optical fiber.

4. at least measuring the distortion surveillance of tensile strain for many cables, described distortion surveillance comprises:

Be used for the sample devices of the spectrum change of measuring Brillouin scattering, described sample devices comprises the first optics input/output end port and the second optics input/output end port, and described the first optics input/output end port is used for sending the first optical signalling and described the second optics input/output end port for sending the second optical signalling; With

First group of many cable, described first group of many cable comprise the first cable and last cable, each cable in described first group of many cable comprises strain transducer and temperature sensor, described strain transducer comprises strain optical fiber, described temperature sensor comprises temperature optical fiber, described strain transducer and temperature sensor are extending longitudinally along corresponding cable, described strain optical fiber and temperature optical fiber have close end and distal portion, the fibre-optic close end of described strain and the fibre-optic close end of temperature are positioned at the close end place of corresponding cable, wherein:

The fibre-optic distal portion of described strain of each cable and the fibre-optic distal portion of described temperature each other optics are connected,

The first optics input/output end port optical communication of the fibre-optic close end of strain of the first cable in described first group of many cable and described sample devices, and the second optics input/output end port optical communication of the temperature optical fiber of the last cable in described first group of many cable and described sample devices, and

The fibre-optic close end of temperature of described the first cable is connected with the fibre-optic close end optics of strain of described last cable, to form optical fiber ring, in described optical fiber ring, the described strain optical fiber of each cable in described many cables and the first optics input/output end port of described temperature optical fiber and described sample devices and the second optics input/output end port optical communication, and described the first optical signalling and the second optical signalling enter described optical fiber ring along contrary direction.

5. system according to claim 4, wherein, each cable in described more than first cable is the heavy cable that comprises at least two vertical structure elements, at least one in described at least two vertical structure elements is the core that comprises electric conductor, the strain optical fiber of each heavy cable is arranged in bending neutral region, described bending neutral region surrounds and comprises the neutral longitudinal axis of bending of described cable, and

Wherein, at least one mechanical attachment in described strain transducer and described at least two vertical structure elements.

6. system according to claim 5, wherein, the described strain transducer of each heavy cable is embedded in strain transfer filler, described strain transfer filler is at least one and described strain transducer mechanical attachment in described at least two vertical structure elements, makes at least in strain regime, at least one strain standing in described at least two vertical structure elements is passed to described strain transducer.

7. according to the system described in any one in claim 4 to 6, wherein, the temperature sensor of each cable in described first group of many cable extends and is encapsulated in element extending longitudinally with the structure loosening along the length of described cable.

8. system according to claim 6; wherein; described strain transducer in each heavy cable comprises and surrounds described strain fibre-optic protection sheath, and wherein said strain transfer filler surround described protection sheath and with described protection sheath fit.

9. according to the system described in any one in claim 4 to 8, also comprise that more than first group is supplied with cable, described more than first group supply cable comprises the first supply cable and the last cable of supplying with, described many each that supply with in cable are supplied with cable optics and are connected to the respective cable in described first group of many cable, described the first supply cable is connected with described the first cable optics and described last supply cable is connected with described last cable optics, wherein:

Described more than first group each that supply with in cable is supplied with cable and is comprised the first supply optical fiber and the second supply optical fiber, and described the first supply optical fiber and second is supplied with optical fiber and comprised respectively close end and distal portion,

Described first supply with fibre-optic distal portion and second supply with fibre-optic distal portion respectively optics be connected to described strain optical fiber and the temperature optical fiber of respective cable, and

By the described first fibre-optic close end of the first supply of supplying with cable is connected with the first optics input/output end port of described sample devices, and be connected the first optics input/output end port optical communication of the strain optical fiber of described the first cable and described sample devices with the second optics input/output end port of described measuring equipment by supplying with fibre-optic close end by second of described last supply cable.

10. system according to claim 9, wherein, it is cable that described more than first each that supply with in cable is supplied with cable, described the first supply optical fiber and second is supplied with optical fiber and is integrated in described cable with the structure loosening, and on the end of heavy cable that optics connection occurs, each is supplied with cable and is electrically connected to corresponding heavy cable.

11. according to the system described in any one in claim 4 to 10, and wherein, each cable in described more than first cable is arranged on corresponding movable equipment.

12. systems according to claim 11, wherein, described movable equipment is crane, described crane comprises supporting construction and is rotatably arranged on the spool in described supporting construction, described respective cable can be wrapped in unwinding on described spool and from described spool, and described respective cable is bonded on described spool in its distal portion.