CN103926061B - 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

For measuring the deformation monitoring method and system of the elongation strain of cable

The application is entitled " cable and the method for the strain at least one cable of detection with strain transducer and monitoring system ", the divisional application that international filing date is on May 27th, 2009, the application for a patent for invention that international application no is PCT/EP2009/056428, national applications number is 200980160074.9.

Technical field

The present invention relates to a kind of cable, integrated strain transducer of the cable with the measurement for being particularly well-suited to the strain of static and dynamic tensile.

The invention further relates to it is a kind of at least measuring at least one cable in strain monitoring method and system.

The invention further relates to it is a kind of for detecting a plurality of cable in strain monitoring system and method.In particular it relates to monitor the monitoring system and method for a plurality of cable in movable equipment using Brillouin backscattering technology.

Background technology

In particular for heavy-duty applications and/or for movable fixture（Such as may move portal crane, ship to shore container crane, ship decrater, paver and tunnel winning equipment）Cable be designed specifically to and withstood harsh environment condition and high mechanical stress, such as tension force and moment of torsion.As for heavy-duty applications cable other example, for supplying current to deep-well in submersible pumping systems down-hole pump cable be commonly installed in physically restricted region and unfavorable environment in, Jing is often contacted with corrosivity well fluid.Typically, above-mentioned cable is designed to firm and flexibility.In this specification, when referring to the cable for heavy-duty applications, and when being in particular, though not exclusively, for the cable of movable fixture, we will commonly referred to heavy duty cables.

The example of heavy duty cables is provided in DE3934718, DE3934718 is described for ore deposit The dragging cable with armouring of the cutter-loader in well.

WO01/78086 discloses a kind of cable of the picking up system or commodity shelf system for being particularly used for such as crane.The cable includes core, and the core includes the first conductor, and first conductor bears base material and surround completely and be embedded in the first stress and bears in base material by the first stress.At least one other layer is arranged in the first stress and bears substrates perimeter and have at least one other conductor in the other layer, and at least one other conductor bears base material and surround completely and be embedded in the second stress and bears in base material by the second stress.It is said that the strain in cable is born base material allowable stress and is distributed on whole piece cable and therefore is substantially reduced and is threadingly advanced effect.

Tensile load and distortion in removable cable can be by cable in the mandatory guidance being wrapped in around spool and during the unwinding stage or by basket（For example, for the electric cable that paves）The collection of interior cable is produced.Winding and unwinding stage are typically discontinuous and typically unexpected（For example when being caused by the horizontal movement of crane）, therefore apply significant dynamic tensile load on cable, and therefore the single conductor in cable on apply significant dynamic tensile load.Additionally, for other systems of cable movement, such as pulley system and treatment（tender）System, generally applies during operation high tensile load on cable.

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

US5,767,956 descriptions provide monitoring arrangement using backscatter Brillouin light, no matter optical fiber is normally also to be close to rupture, the monitoring arrangement can be observed in real time.By using one of the optical fiber core in optical cable, the device uses optical time domain reflectometer（OTDR）To monitor the Brillouin scattering for exciting.Without the hint for using in providing with regard to cable.

The system that WO08/073033 describes bending and strain that a kind of strain for being connected to by measurement or being incorporated in the optical fiber of cable is used to monitor the cable for being connected to mobile offshore platform.Strain will be produced in optical fiber for bending in cable and this strain will change the optical property of fiber.The change of optical property can pass through optical time domain refiectometer（OTDR）Or optimal frequency domain reflectometer（OFDR）It is measured.

This document is not in the face of protecting strain transducer from outside mechanical stress to avoid the damage of sensor and the problem of the long-term reliability for ensureing to measure.Conversely, the application statement exists and is embedded in or is connected to the optical fiber of cable and can be vitiable dangerous and therefore propose to be equipped with unnecessary fiber for cable.Additionally, the problem of the strain transfer between not referring to fiber and wanting measured cable.As the possibility position for fiber, the space between armor wire is referred to.

US2004/0258373 describes a kind of composite cable that can be embedded in building, heaving pile or pipeline, and the composite cable includes the Optical devices for monitoring temperature and strain.The cable include outer protection sheath and for monitor temperature and strain Optical devices, the Optical devices in the outer protection sheath and including：First pipe, the first pipe includes at least the first optical fiber to monitor temperature, first optical fiber is loosely in the first pipe and including at least one reflecting part for being referred to as Bragg grating, the first pipe includes at least the second optical fiber, at least second optical fiber includes at least one Bragg grating to monitor strain, the cable is characterised by, outside the first pipe, the Optical devices also include the device for fastening second optical fiber to second optical fiber.

Applicant have noticed that, this document does not disclose the cable with integrated strain optical fibre transducer or with integrated temperature sensor.Disclosed cable is composite cable, the composite cable can include power cable, but with for strain and temperature monitoring fiber separation.

EP0203249 discloses medium voltate（6 arrive 60kV）Cable, the cable includes at least one temperature and/or tension pick-up optical fiber.

Applicant have observed that, disclosed integrated strain transducer optical fiber in the cable can significantly by the Bending Influence of cable（Depending on the amount of the bending of optical fiber position in the cable and/or cable, particularly when more than a certain value）.

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 analysis sensing optical fiber cable（That is, for sensing the cable of the strain of associated apparatus or system）Different structure.The compactness of the layer in straining and sensing optical fiber cable is considered as very important and can be by the peeling force between cable floor and strain transfer ability（I.e., it is possible to be delivered to the maximum strain of internal fiber with not reducing from cable outer layer）Description.

This document does not refer to any application that disclosed sensing optical fiber cable is monitored to the cable of electric power or cable.

WO07/107693 discloses a kind of optical fiber cable, and the optical fiber cable includes strain transfer component, through the central optical fiber of strain transfer component arrangement and by central optical fiber and the tight sheath of strain transfer component mechanical attachment.The strain that strain transfer component undergoes is delivered to central optical fiber by tight sheath.

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

The applicant has faced how to realize being particularly suitable for heavy-duty applications, and more particularly it is suitable for the problem of the cable of movable fixture, during operation the cable will allow controlling for the elongation strain that is subject to of cable, and the real-time monitoring of the elongation strain is preferably allowed for, while ensureing the long-term reliability of measurement.

Especially, the applicant has been processed by performing the problem of measurement in the cable by sensor, and the sensor keeps the outside mechanical stress being not substantially affected by addition to being applied to the elongation strain on cable to affect.

The content of the invention

The high mechanical stress applied during due to operation, heavy duty cables（Such as it is used for mining application or crane equipment）Typical life be typically relatively short, and depending on concrete application can several moons between the several years change.Applicant have observed that, it would be advantageous to, there is provided the heavy duty cables that can be monitored during its operation.By the time-evolution for understanding cable status, the effective periodic maintenance of cable can be performed, for example, guide reel failure can be adjusted and/or the electric control parameters of the automatic system of movable equipment are adjusted.

Making regular check on for cable status can be " offline ", cable be not used by or or even from its equipment mounted thereto be removed, but in fact, because the loss of the necessary working time for stopping due to the device comprising cable, does not generally perform this inspection.

Will particularly advantageously, record causes the dynamic event of elastic strain peak value during cable work, however, the dynamic event can damage cable due to fatigue.And, this monitoring can prevent undesirable deactivation event and save relevant cost.

It is an object of the present invention to provide a kind of cable with strain transducer, the strain transducer can provide reading for the measurable prolongation of sizable scope, sizable scope in particular from 0.1% to 1%, preferably from -0.2% to 1%.Higher prolongation value can also be measured, for example, reaches 2% or even up to 4%.

In this case, in fact it could happen that the reduction of the speed of digital independent, this can affect " real-time " collection from the data of monitored cable.

It is another object of the present invention to provide a kind of cable with strain transducer, the strain transducer measurement dynamic tensile load, the strain broken out in the Part portions for especially monitoring the length of cable, it is thus determined that the damage that fatigue causes.

The other target of the present invention is to provide a kind of monitoring system, and the monitoring system may be used for detection by inter deterioration or by unsuitable（For example, by do not meet cables manufacturing person offer recommendation use）The permanent damages of the cable for causing.

The another target of the present invention is to provide a kind of monitoring system, and the monitoring system is used at least monitor the elongation strain of a plurality of cable for being especially heavy duty cables in movable equipment.

Usually and according to one side, the program is related to a kind of cable, and the cable includes at least two vertical structure elements and the optical fiber strain transducer for monitoring the elongation strain of the length along cable.The strain transducer includes the optical fiber extended along the length of cable.The optical fiber of strain transducer will also be referred to as straining optical fiber below.

According to a further aspect in the invention, there is provided a kind of deformation at least measuring the elongation strain of at least one cable monitors method, the method comprising the steps of：At least one cable is provided, at least one cable includes：Strain transducer, along the cable longitudinal extension and including the strain optical fiber being arranged in bending neutral region, the bending neutral region is surrounded and including the bending neutrality longitudinal axis of the cable strain transducer；The core for including electric conductor with least one of at least two vertical structure elements, at least two vertical structures element, wherein the strain transducer at least in strain regime with least one of at least two vertical structures element mechanical attachment；First optical signalling is introduced into the strain optical fiber；Detect the Brillouin scattering sent from the strain optical fiber；With analyze the spectrum change in the scattered light, at least to measure the elongation strain of at least one cable.

According to another aspect of the invention, there is provided a kind of deformation monitoring system at least measuring the elongation strain of at least one cable, the deformation monitoring system includes：Cable, the cable includes：Strain transducer, the strain transducer is along the cable longitudinal extension and including strain optical fiber, the strain optical fiber has the close end and distal portion being arranged in bending neutral region, and the bending neutral region is surrounded and including the bending neutrality longitudinal axis of the cable；The core for including electric conductor with least one of at least two vertical structure elements, at least two vertical structures element, wherein the strain transducer at least in strain regime with least one of at least two vertical structures element mechanical attachment；And sample devicess, for measuring the spectrum change for straining the Brillouin scattering in optical fiber, the sample devicess couple the sample devicess with least described close end optics of the strain optical fiber, to introduce light into the strain optical fiber.

According to another aspect of the invention, there is provided a kind of deformation monitoring system at least measuring the elongation strain of a plurality of cable, the deformation monitoring system includes：For measuring the sample devicess of the spectrum change of Brillouin scattering, the sample devicess include the first optical input/output port and the second optical input/output port, and first optical input/output port is used to send the first optical signalling and second optical input/output port is for sending the second optical signalling；With first group of a plurality of cable, first group of a plurality of cable includes the first cable and last cable, each cable in first group of a plurality of cable includes strain transducer and temperature sensor, the strain transducer includes strain optical fiber, the temperature sensor includes temperature optical fiber, the strain transducer and temperature sensor are along corresponding cable longitudinal extension, the strain optical fiber and temperature optical fiber have close end and distal portion, the close end of strain optical fiber and the close end of temperature optical fiber are located at the close end of corresponding cable, wherein：The optics connection each other of the distal portion of the strain optical fiber of each cable and the distal portion of the temperature optical fiber，The close end of the strain optical fiber of the first cable in first group of a plurality of cable and the first optical input/output port optic communication of the sample devicess，And the second optical input/output port optic communication of the temperature optical fiber of the last cable in first group of a plurality of cable and the sample devicess，And the close end of the temperature optical fiber of first cable is connected with the close end optics of the strain optical fiber of the last cable，To form optical fiber ring，In the optical fiber ring，The optic communication of both the strain optical fiber and the temperature optical fiber of each cable in a plurality of cable and first optical input/output port and the second optical input/output port of the sample devicess，And first optical signalling and the second optical signalling enter in opposite direction the optical fiber ring.

In this manual, term " vertical structure element " expression substantially partly completes structure along the cable of the length longitudinal extension of cable.As will be clear from according to following, the electric transportation function of cable is contributed to according to the vertical structure element of specification and claims.

At least two vertical structures element that cable includes includes at least one cable core.

Term " core " represents at least one electrical conductivity element for including such as electric conductor and typically comprises the half-done structure of the cable of at least one insulating barrier for surrounding electric conductor.In typical construction, electric conductor includes multiple stranded wires.

Applicant have perceived that, by the mechanical attachment between the vertical structure element and the optical fiber of strain transducer that ensure cable, and especially mechanical fit, strain and be delivered to strain optical fiber from vertical structure element to be monitored.By " mechanical fit ", it is intended that two or more parts are basically as moving integrally or tolerate adaptability to changes.Just now the mechanical fit for describing allows the cable for obtaining the reliable readings that the static state and dynamic tensile load for undergoing can be provided in the prolongation of relatively large range.According to an aspect of the present invention, strain transducer is embedded in strain transfer filler, and the strain transfer filler is by least one mechanical attachment of sensor and at least two vertical structure elements of cable.

Elongation strain is expressed as the length of cable increases the percentage ratio in initial length, and Δ L/L, wherein L are length, i.e., as percentage ratio extended linear length.When cable is due to external force（For example, tensile load）And be forced along during its longitudinal direction stretching, extension, elongation strain occurs.

Applicant have perceived that, strain transducer integrated in the cable and should be arranged so as to maintain substantially do not damaged by the bending with its minimum bending radius of cable.Especially, the applicant has appreciated that, the optical fiber that strain transducer includes should be located below in the bending neutral region of referred to as neutral region, the cross section that the bending neutral region symmetrically extends along cable longitudinal extension and with the neutral axis basically about cable.

As it is used herein, term " neutral region " is intended to describe axis（" neutral axis "）The region of surrounding, at the axis, it is minimum to bend the prolongation for causing.Neutral axis can be defined as the imaginary line of the length along cable, at the imaginary line, in the case where cable undergoes bending, significant linear deformation does not occur and bending stress is small in strain transducer.Preferably, cable design in the position, acts on the torque on cable and determines that the small longitudinal direction of detector fibers extends into causing neutral axis to be located in a position.

The minimum bending radius of given cable（It generally corresponds to minimum profile curvature radius ρ_min, cable allows the minimum profile curvature radius to avoid any permanent damages）, then neutral region can be defined as due to not less than ρ_minThe bending of radius of curvature, strain transducer undergo no more than 2%, and the region of preferably not more than 1% prolongation.Arrangement of the strain optical fiber in neutral region prevents it from rupturing due to cable bend or permanent damages.

In round cable, i.e., in the cable with circular symmetry cross section, neutral region is around the radial zone of neutral axis in the cross sectional planes of cable.In a preferred embodiment, when round cable is referred to, neutral axis is the central longitudinal axis of cable.Preferably, strain transducer is leaving neutral axis less than 0.02 ρ along cable arrangements_min, and no more than 0.01 ρ_minRadial distance in.

According to one side, the present invention relates to a kind of cable, the cable includes：Strain transducer, along the cable longitudinal extension and including the strain optical fiber being arranged in bending neutral region, the bending neutral region is surrounded and including the bending neutrality longitudinal axis of the cable strain transducer；With at least two vertical structure elements, the at least one of at least two vertical structures element is the core for including electric conductor, wherein described strain transducer is embedded in strain transfer filler, the strain transfer filler by least one of at least two vertical structure elements with strain transducer mechanical attachment.By the cable of the present invention, at least in strain regime, at least one strain transfer for undergoing of at least two vertical structure elements is to strain transducer.

Heavy duty cables are designed to bear the lateral load and tension force of the vertical structure element in compression cable.Applicant have observed that, it would be advantageous to, strain transducer keeps the lateral compression for being not substantially affected by cable to affect, and the lateral compression can cause the light loss due to microbend when strain optical fiber is affected.Additionally, when the optical fiber of strain transducer is compressed, a part of of the lateral load applied transverse to the direction of cable longitudinal axis can improperly be changed into elongation strain change.Especially, it has been observed that, when lateral compression is applied along direction that is vertical or being generally transverse to cable longitudinal axis, if lateral compression is delivered to optical fiber, the strain variation along that axis can be caused parallel to the part for straining fibre axis.

Preferably, the neutral axis of cable is selected so as not to can substantially write the lateral compression being subject to along the direction of the horizontal longitudinal direction in cable.It has been found by the present applicant that advantageously, surround strain optical fiber to improve the mechanical resistance to lateral load, the optical fiber for optionally buffering of the protection sheath directly contact strain transducer with protection sheath.Preferably, sheath is protected to include the composite that fiber is strengthened.

Cable typically undergoes one or more heat treatments, especially solidification process during its manufacture, and the solidification process is related to the heat treatment of the last for several minutes under about 150-200 DEG C of representative temperature.Applicant have noticed that, it is preferred that the material of the solidification process occurred during the manufacture of the cable that strain transfer filler and strain transducer are integrated in including tolerance strain transducer, while maintaining：（1）The elastic property of strain transducer, at least in cable has the scope of elastic performance, the elastic property realizes the permanent deformation of the reversibility without strain transducer of strain transducer, and（2）Adhesion or to the high frictional resistance of undesired sliding so that the mechanical fit between sustaining layer and cable element.

Preferably, sheath is protected to be made up of the composite that fiber is strengthened, wherein reinforcing fibre is carbon, graphite, boron, aromatic polyamides or glass fibre；The polymer of embedding reinforcing fibre is preferably crosslinked resin, for example, 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.Strain transfer filler is elastic at least in cable has the range of strain of elastic performance.

Applicant have noticed that, it would be advantageous to, it is that cable arranges temperature sensor.

The operation temperature of heavy duty cables can change 90 DEG C from -50 DEG C, wherein -50 DEG C be work during minimum environment temperature, and 90 DEG C be operation during the maximum temperature that reaches of electric conductor.Longitudinal direction local across the internal temperature for being sometime spaced average cable increases（That is, increase without peak）The presence for damaging can be indicated, the damage causes the increase of such as conductor resistance and local Joule loss.Additionally, electric load affects overall cable temperature, and therefore, the Arrhenius models that reference prediction is accelerated due to failure that temperature increases, the monitoring of cable temperature allow the residual life of prediction cable and therefore permission cable in good time planned replacement.

Temperature monitoring can be used to eliminate the caused strain due to the temperature effects in the optical analysiss based on Brillouin.

For the temperature survey that the Warm status for carrying out the fibrous glass of only strained optical fiber affect, optical fiber should be without mechanical stress, and especially, should be not substantially affected by the elongation strain of the cable that it is integrated in affects.In some preferred embodiments, temperature sensor is integrated in the cable, and wherein temperature sensor includes optical fiber, and the optical fiber is loosely inserted in the module of the longitudinal extension twisted together with the vertical structure element of cable.In such configuration, the loose degree of cable（That is, the amount of the excess fiber length in pipe）So that cable（Accommodate with fiber and manage）Expected maximum extension be it often fully compensated so that without obvious strain transfer to temperature sensing optical fiber.

In some preferred embodiments, cable is the round cable with substantially circular cross section and is diametrically disposed at least three outside vertical structure elements including relative to strain transducer.

Description of the drawings

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

For this description and the purpose of claims, unless otherwise noted, expressing all numbers of quantity, amount, percentage ratio etc. will be understood to be modified by term " about " in all cases.And, all scopes include disclosed minimum and maximum point and including the therein any intermediate range that can specifically enumerate here or specifically not enumerate.

Fig. 1 a are the perspective illustrations of cable according to an embodiment of the invention.

Fig. 1 b are the schematic sectional views of the cable illustrated in Fig. 1 a.

Fig. 2 a are the perspective illustrations of the strain transducer used in the cable of the present invention.

Fig. 2 b are the schematic sectional views of the strain transducer illustrated 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 illustrating cable according to an embodiment of the invention in the backscatter technique based on Brillouin operating principle.

Fig. 8 is that the figure of the monitoring system of the strain and temperature of a plurality of heavy duty cables being arranged in movable equipment according to an embodiment of the invention is represented.

Fig. 9 is the partial side view of C-C along the line, illustrates the heavy duty crane of the monitoring system of Fig. 8.

Figure 10 is schematic diagram, illustrates the operating principle of the monitoring system of a plurality of heavy duty cables in embodiments of the invention.

Figure 11 is that the figure of the monitoring system of the strain and temperature of a plurality of heavy duty cables in movable equipment according to other embodiments of the present invention is represented.

Figure 12 is schematic diagram, illustrate the present invention additional embodiment in a plurality of heavy duty cables monitoring system operating principle.

Specific embodiment

Fig. 1 a and 1b are shown respectively the perspective view and sectional view of cable according to an embodiment of the invention.The cable for illustrating of the present embodiment may adapt to heavy-duty applications, more specifically be suitable for movable fixture.Cable 1 is the round cable for including three cores 2, and three cores are arranged radially at the central longitudinal axis Z of cable（It is visible in fig 1 a）Around.Core 2 can provide three-phase power transmission.Cable 1 can be low or medium voltate cable, and wherein low-voltage is represented until the voltage and medium voltate of 1kV represent the voltage from 1kV to 60kV.Each core 2 includes electric conductor 12, for example, the copper conductor formed by a branch of tin plating or exposed copper electric wire for twisting together according to conventional methods.In the radially external position relative to each electric conductor 12, internal semiconductive layer 13, insulating barrier 16, outside semiconductive layer 17 are sequentially arranged.Internal semiconductive layer 13, insulating barrier 16 and outside semiconductive layer 17 are made up of the material based on polymer, and the material that should be based on polymer is extruded or be expressed into jointly on conductor 12 in which can be stacked.Insulating barrier 16 can be the ethylene propylene rubber of such as crosslinking（EPR）；Inside and outside semiconductor layer 12 and 17 can be EPR, the ethylene/propylene/diene terpolymers of the conductive filler for example filled with suitable amount（EPDM）Or its mixture, the conductive filler typically can be white carbon black.

Alternatively, in the case of mode of operation permission, insulating barrier and semiconductor layer can be made up of the thermoplastic compound for being such as based on polyacrylic compound.

In some applications, cable core 2 includes at least one metal screen layer 22 in the radially external position relative to outside semiconductive layer 17.

It should be appreciated that the above description of core 2 only represents one kind of the possibility structure of the core that cable includes, the core generally could be for power transmission or the phase core of ground connection, the core for transporting control signal or transport the core of electric power and control signal.

Feature of the invention, cable 1 includes optical fiber strain transducer 5.

The fact that undergo frequently mechanical stress during their life-span due to heavy duty cables, applicant have perceived that, it is especially appropriate, strain transducer is positioned in cable and causes cable bend to not less than minimum profile curvature radius ρ_minAny radius of curvature not breakdown strain optical fiber, the minimum profile curvature radius can be bent without the least radius of permanent damages corresponding to cable.Cable bend causes prolongation in strain transducer.It has been observed that with not less than ρ_minRadius of curvature cable bend（At this moment, the longitudinal strain that causes of bending less than typically 1 or 2% strain testing in be applied to the strain of fiber）Usual not breakdown strain sensor.

The region for keeping the cable of the length extension of unspoiled cable along strain optical fiber due to cable bend is defined as cable（Bending）Neutral region.In round cable, in the cross sectional planes of cable, neutral region is the radial zone with regard to neutral axis, and in the present embodiment, the neutral axis corresponds to central longitudinal axis Z.

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

Applicant have observed that, it is heavy duty cables, especially for the ρ that the application in movable equipment is specified_minValue can be with relatively low, for example, 250mm, and therefore, in order to ensure the bending resistance of strain transducer, neutral region should have the relatively small radial distance for leaving central longitudinal axis, for example, no more than 5mm.For example, all the time with reference to circular cable, for ρ_min=300mm, is 3mm to have 1% radial distance of prolongation.

In some preferred embodiments, neutral region is arranged in along the length of cable and leaves central longitudinal axis（That is neutral axis）Less than 0.02 ρ_min, and preferably no more than 0.01 ρ_minDistance in.

Especially, it has been observed that being probably favourable substantially along central longitudinal axis arrangement strain transducer, this is because, in some practical situations, its axis of symmetry corresponding to radially outer core, and/or as described below, it can be with simplified cable fabrication process fit.

Except being used for transmitting the core 2 of electric power and/or control signal, cable 1 also includes at least one earth conductor 7.In the embodiment illustrated in Fig. 1 a and 1b, the cable includes two earth conductors 7 for example in the form of a branch of stranded tin plating or exposed copper electric wire.In particular for medium voltate application, this beam electric wire of earth conductor can be by semiconductor layer（Not shown in figure）Surround.Earth conductor 7 is radially outward arranged relative to strain transducer 5 and twisted together along cable longitudinal direction with core 2.Especially, according to conventional methods, core 2 and earth conductor 7 is spiral is wrapped in around the central longitudinal axis Z of cable.

In the embodiment for illustrating in figures ia-ib, cable 1 includes fibre optic element 3, and the fibre optic element includes a plurality of optical fiber for transmission of control signals, sound, video and other data signals, such as 6 to 24 optical fibers.Wall scroll optical fiber or fiber to the module 19 of the longitudinal extension being preferably fabricated from a flexible material can be inserted in Loose-tube buffering construction in, the flexible material such as polybutylene terephthalate (PBT)（PBT）Or ETFE（ETFE）.In the example for illustrating, it is the SZ for spirally winding longitudinal strength component 18 to wrap fibrous module, and the longitudinal strength component is such as glass fibre, aramid filament or carbon fiber.Fibre optic element 3 can be twisted together with core 2 and earth conductor 7.Generally, if cable construction is allowed, earth conductor and fibre optic element can be arranged in the external void of the formation of core 2.

Core 2 and earth conductor 7（If present）And/or fibre optic element 3 is referred to collectively as the vertical structure element of cable.

The elongation strain that cable undergoes is tended to be delivered to the strain transducer for measuring cable strain.For strain transfer, strain transducer is mechanically consistent with least one of cable vertical structure element so that the strain that at least one vertical structure element undergoes is delivered at least in part but significantly strain transducer.For this purpose, strain transducer 5 is embedded in strain transfer filler 6, the strain transfer filler is mechanically coupled to strain transducer with least one vertical structure element of cable.Preferably, each of strain transfer filler by strain transducer with integrated core in the cable is mechanically coupled to, and is more preferably mechanically coupled to each of vertical structure element circumferentially.

Applicant have perceived that, strain and cable that strain transducer is measured（That is at least one vertical structure element of cable）Relation between the strain for undergoing should cause the prolongation that cable undergoes clearly to associate with the prolongation of sensor optical fiber, and therefore clearly associate with the measured value of strain.

The applicant has appreciated that, in order to ensure that the univocality between the prolongation of strain transducer and the prolongation of cable is associated, the contact between strain transfer filler and at least one vertical structure element at least should not show significant slippage loss under strain regime.It is of concern in most cases, there is no that slippage loss means the adhesion by frictional force or bonding between them between sensor and element.Due to cause substantially the same deformation without significant slippage loss between element two elements between mechanical attachment be referred to herein as mechanical fit.

In the embodiment for illustrating in figures ia-ib, the geometric construction of strain transfer filler 6 causes the filler when cable is in substantially free of strain regime also to contact the multiple vertical structure elements being arranged in relative to strain transducer 5 in radially external position.

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

As used herein, it is intended to be described in the fiber of strain transducer the reference state of the cable with average reference strain with " there is no the state of strain ", the reference state can correspond to the state before the original cable hank carrying cable of the cable provided from manufacturer（Such as, it is being transported to winding and is anchoring spool or treatment（tender）Before pulley system）.However, in most of practical situations, after reference state refers to be arranged in movable equipment, i.e., after transmitting from original cable hank, and before the use, therefore in the cable being exposed to before relevant tensile load.It is preferred that reference state can correspond to the state of the cable being arranged on crane, the crane is arranged on its maximum and extends, i.e., cable is used for the major part of its length.The measurement that the applicant realizes is it has been shown that in the state that there is no strain, in the cable including 250 μm of optical fibers of single mode as strain optical fiber, strain varies to 0.3% from -0.2%.Different due to manufacturing situation, the cable strain can be along the length change of cable, although with overstrain（The overstrain is generally longitudinally constant）Cable be preferred（Because it can simplify the monitoring of cable of the invention）.

The state that there is no strain provides reference value, relative to the strain of the cable in the reference value measurement use.In measurement along Brillouin's method of the strain of the distribution of lengths of cable, there is no that the state of strain also refers to the multiple reference values measured in different parts along the length of cable.

As herein defined, strain regime means any state of the state for being different from there is no strain.Tensile stress in cable can be measured as strain deviation, i.e., relative to the cable extension of average reference value in the case of increment or cable compressed in the case of decrement.

Strain transfer filler 6 is made up of the material with elastic property, to show elastic performance without the permanent deformation of filler on cable（The reversibility for deforming）Maximum strain react.Strain transfer filler is selected to suitably be stretched and when external tension load along the cable for undergoing to extend（At least for corresponding to the tensioning load for allowing maximum strain, in the case of allowing maximum strain more than this, the permanent and irreversible deformation of cable occurs）Substantially recover deformation when being removed.

Strain transfer filler 6 can be based on polymeric material, advantageously be extruded around strain transducer 5.In relatively large range of strain（For example, more than 1%）The interior thermo-setting elastomer with elastic performance is found to be particularly suitable for the cable of the present invention.Advantageously, thermo-setting elastomer is observed the surface for adhering to vertical structure element with high frictional force.For example, it has been noted that, thermo-setting elastomer provides the strong bonding with the semi-conducting material of the core for typically surrounding some cables, while showing the frictional force harmless to the quasiconductor outer surface of core.It was observed that the reliable strain transfer with the relation between the strain measured in strain that is predicable or at least can experiencing in the vertical structure element of derived cable and sensor occurs.

Advantageously, the material of strain transfer filler has tolerance to heat treatment, during the heat treatment is likely to occur in cable fabrication, such as cable external jacket solidification（Perform typically at a temperature of about 200 DEG C）Period.

Preferably, strain transfer filler includes the thermo-setting elastomer by steam pressure, the radiation by electron beam, salt bath dipping or the crosslinking of crosslinked with silicane system.Generally, strain transfer filler is preferably made up of the elastomer with the elastic modelling quantity between 0.01 and 0.7GPa.For example, group of the strain transfer filler selected from following thing composition：Ethylene propylene diene rubber（EPDM）, EP rubbers（EPR）, nitrile rubber（NBR）.

Although thermo-setting elastomer because their heat-resisting sticking property and big elastic range but it is preferred, be not excluded for using thermoplastic elastomer (TPE).The example of thermoplastic elastomer (TPE) includes styrenic-diene-styrene triblock copolymer；Thermoplastic polyester elastomer and Polyurethane Thermoplastic Elastomer；And thermoplastic polyolefin rubber（Polyolefin blend）.

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

Polymer filler of the void area 11 filled with the compound for being such as based on EPR.External jacket 14 is for example provided by extrusion.In order to increase repellence of the cable to mechanical stress, external jacket 14 preferably by the heavy thermo-setting elastomer for being based preferably on reinforcement solidification polymeric material（Such as, high density polyethylene (HDPE)（HDPE）, polychlorobutadiene, polyurethane or the compound based on NBR）Make.

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

Applicant have perceived that, in order to ensure that strain transfer occurs between the optical fiber of strain transducer and the vertical structure element of cable across the gamut of the measurable magnitude for extending, advantageously, strong and substantially uniform bonding is present in surrounds between optical fiber and the layer that is mechanically coupled to optical fiber and strain transfer filler.This allows the mechanical fit between the optical fiber and strain transfer filler of strain transducer.

Fig. 2 a and 2b are shown respectively the fragmentary perspective view of the strain transducer 5 being integrated in the cable of Fig. 1 a and 1b according to a preferred embodiment of the invention and cross section.Strain transducer 5 include optical fiber 9, when strain transducer it is integrated in the cable when, the optical fiber along a substantially longitudinal axis Z arrangement.The fiber 9 of strain transducer 5 is optical fiber, optical fiber i.e. based on silicon dioxide, the optical fiber has 125 μm of Typical nominal diameter, coated by primary coating, the primary coating is surrounded by secondary coating, the secondary coating typically adhesively contacts primary coating, and wherein primary coating and secondary coating forms coat system.（Coating）The external diameter of optical fiber can be 250+/- 10 μm or 200+/- 10 μm.Signal layer coating system can also be used.Preferably, optical fiber 9 is single mode optical fibre, is such as met G.652, G.653 or G.655ITU-T（Union of International Telecommunication, ITU telecommunications portion）The transmission fiber of recommendation.In embodiment, strain optical fiber is pure silicon dioxide core fibre.

Preferably, the optical fiber of strain transducer has the bending property for improving, and loses with low bending.In certain embodiments, optical fiber meets and G.657ITU-T recommends.

For identifying purpose, it is probably favourable to have coloured optical fiber；In this case, it is preferable that using the optical fiber for having coloured secondary coating.It can be advantageous to select any color in addition to white.

Applicant have observed that, the optical fiber of strain transducer is resistant to reach 1%, and the repetition for preferably reaching 2% extends the number of times for being continued above the motion cycle for expecting in the cable to occur during the operation lifetime of cable.It can be noted that the value of 1% strain is more than the typical maximum extension that cable can bear before rupture or permanent damages（For example, 0.5-0.7%）.Coat system can be made up of the acrylate material of the two of the diameter for reaching 250 μm different UV solidifications.In one embodiment, as disclosed in EP1497686, EP1497686 is observed and provides the optical fiber not ruptured when undergoing the repetition more than 2% and extending the coat system of glass fibre.

In a preferred embodiment, optical fiber 9 for example, resists micro-bending losses by surrounding the cushion 10 of coat system by tight buffer to improve the mechanical protection of optical fiber.The applicant has appreciated that cushion is to optical fiber（Arrive the coat system of fiber）Uniform adhesion 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 μm of coatings, and external diameter is increased to into 600-1000 μm, and representative value is 800-900 μm.Preferably, cushion is made up of the material with elastic property, and the material allows the optical fiber of tight buffer to bear the prolongation reached and including 2%.

Advantageously, cushion is selected to adhere to the coat system of optical fiber, there is no creep, sliding or stripping.Preferably, cushion is based on the heat proof material of the thermal resistance with the heat treatment occurred during being enough to withstand cables manufacturing.

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

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

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

The applicant it has been observed that, it would be advantageous to, the optical fiber of strain transducer is protected from lateral load, and the lateral load can cause micro-bending losses and therefore can affect the Brillouin shift measured in fiber.Additionally, as described above, when fiber is affected by lateral compression, strain transducer can provide not with the measured value of the elongation strain of effective prolongation direct correlation of cable.For this purpose, the protection sheath 8 for being designed to improve the resistance to lateral compression can be advantageously arranged to the optical fiber for surrounding optionally tight buffer.

In the circular cable illustrated in such as Fig. 1 a and 1b, transverse to the lateral compression in the direction in longitudinal cable direction direction radially inward is typically occurred in.

Applicant have observed that, during cable fabrication process in the extrusion step of strain transfer filler, strain transducer can serve as tensile strength component.For this purpose, having been observed that, it is important that strain transducer material does not soften during the extrusion of strain transfer filler, to ensure uniform pulling force.The presence of protection sheath 8 and the appropriate selection of the material for forming the sheath can be advantageously strain transducer and provide tensile strength, and the tensile strength be enough to improve the resistance to lateral compression and allow strain transducer to serve as tensile strength component in the manufacture process of cable.

In order to ensure the mechanical fit between optical fiber and strain transfer filler, the material of protection sheath is selected to provide the strong and relatively uniform adhesion with the optical fiber for optionally buffering.

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

In embodiment, protection sheath 8 is glass-reinforced polymer（GRP）, wherein the polymer is by the glass fibre reinforcement being embedded in the polymer.It has been observed that the presence parallel to the reinforcing fibre of optical fiber longitudinal axis arrangement realizes the advantageously relatively high anti-tensile rigidity of strain transducer, therefore prevent lateral compression from being misread as elongation strain.Protection sheath 8 in pultrusion to cushion 10 and can be in direct contact with it.

Optionally, multiple grooves or otch are included by the outer surface that strain transducer is embedded in the protection sheath that strain transfer filler therein is surrounded or is processed to form rough surface, to increase the adhesion of protection sheath and strain transfer filler.Alternately or in addition, adhesion promoting layer can be optionally disposed on protection sheath.

As described above, strain transducer should have elastic response to return to its initial condition after tensile load is removed from cable, the tensile load is associated with greatest hope cable strain.In order to provide with required flexible strain transducer, it is preferred that protection sheath based on the material of polymer by being made with elastic property.Preferably, the polymer for embedding reinforcing fibre is crosslinked resin, in particular the curable crosslinked resins of UV or thermoset cross-linked resin, the commonly provided resistance to compression pression of the crosslinked resin.Crosslinked resin can be unsaturated polyester (UP), epoxy resin or vinyl esters.

It has been observed that the flexibility in order to improve strain transducer, when by being made based on the material of polymer, the thickness for protecting sheath is preferably included between 500 and 1000 μm.For example, sheath is protected to be GRP layers, the external diameter of the optical fiber of buffering is increased to 1.8-2.5mm by the GRP layers.

Preferably, surrounding the protection sheath of the optical fiber of sensor prevents fiber in the fabrication process, and especially in some cable assemblies（Such as inside and outside sheath）Solidification process used at a temperature of shrink.

Selection withstands the high-temperature level crosslinked resin of solidification temperature, such as high temperature of Polystal Composites GmbHGRP。

According to one side; the present invention relates to strain transducer; the strain transducer includes optical fiber, closely surrounds the cushion of optical fiber and surround the protection sheath of cushion; wherein cushion is made up of heat proof material; preferably it is made up of the acrylate polymer of radiation-curable, and protects sheath to be made up of the composite that fiber is strengthened.Preferably, the reinforcing fibre during the composite of fiber reinforcement is by being embedded in crosslinked resin is reinforced.Preferably, cushion is made up of the curable acrylate polymers of UV.

Preferably, in order that strain transducer can also detect the little compression of cable, the optical fiber of buffering is placed in the composite of fiber reinforcement with the state for slightly stretching corresponding to 0.2% pre- prolongation.

Strain transducer can detect the measurable prolongation of relatively large range, especially from -0.2% to 1%.Because the prolongation for being up to 1% can occur in 0.5-0.7% with measured and in view of cable gross fracture（And typically smaller than 1%）Prolongation under, therefore, once it is maximum allowable strain it is measured in a position of cable, strain transducer of the invention can just detect the permanent deformation of cable.

Strain is delivered to next layer from one layer at least in part, therefore ensure the reliable measurements of the cable extension in relatively large scope, and while ensure that at least in scope of the tensile load less than the permanent deformation of cable elastic return is to the state that there is no strain when tensile load is removed.Due to strain transducer and the material of strain transfer filler（The material provides the mechanical fit between different elements）Appropriate selection, it is ensured that the knowable relation between efficient strain transfer and fiber elongation and cable strain.In some cases, the strain transfer expection from the radially outer vertical structure element of cable to the optical fiber of strain transducer varies to 100% from 50%.

In above preferred embodiment, strain transducer includes optical fiber, and the optical fiber is by the layer with elastic property（That is, tight buffer, protection sheath）Cover and be embedded in the strain transfer filler with elastic property.But; as long as the structure being made up of strain transducer and strain transfer filler can recover the prolongation in the reversible elasticity region of cable, then at least one of the layer of the group of cushion, protection sheath and strain transfer filler composition selected from the fiber for surrounding coating can have inelastic behaviour and especially have plastic property.Especially, this at least one layer can be made up of plastic material, the plastic material i.e. material with following ability：Do not rupture in response to mechanical force deformation, at least up to a certain threshold value less than external force.The applicant has appreciated that elastic response needs：（1）Layer and at least one of which fit by made by elastomeric material by made by the material of substantially plasticity；With（2）The axial stiffness of layer is less than the least one layer of axial stiffness by made by elastomeric material that the layer of plastic material is in contact with it by made by plastic material.The axial stiffness typically measured with N is the product of the cross-sectional area of Young's moduluss and layer elements.So, the layer by made by the material of substantially plasticity adheres to by frictional force along it during cable extension or contacts elastomeric material stretching, extension thereon and is withdrawn into its home position by elastomeric material（As long as enough chucking powers are present between this two-layer）.

For example, the protection sheath of strain transducer is the thermoplastic polymer of the fiber reinforcement of the Young's moduluss with 72,400MPa, and strain transfer filler is the thermo-setting elastomer of the Young's moduluss with 671MPa.The cross-sectional area of protection sheath is 3.4mm²And the cross-sectional area of strain transfer filler is 75mm², for the axial stiffness for protecting sheath to provide the axial stiffness of 250kN and for strain transfer filler provide 50kN.As the thermoplastic polymer that fruit fiber is strengthened adheres well to strain transfer filler and adheres to the layer being located below（Such as cushion）, then thermoplastic polymer carry out with strain transfer filler, even if its cross-sectional area is much smaller.It will be noted that, it is assumed that meet above-mentioned condition（1）With（2）, and wherein the layer with elastic property is the cushion for being protected sheath to surround, if strain transfer filler is made up of thermoplastic polymer, this will be also correct.

In embodiment, condition is being met（1）With（2）Hypothesis under, strain transfer filler selected from following thing composition group：With 1 to 5GPa Young's moduluss polyester, with 2 to 4GPa Young's moduluss polyamide, with 0.003 to 0.01GPa Young's moduluss polrvinyl chloride（PVC）, with 0.1 to 0.3GPa Young's moduluss Low Density Polyethylene, and with 0.4 to 1.2GPa Young's moduluss high density polyethylene (HDPE).Preferably, using crosslinked polymeric materials.

According to another embodiment, in order to provide the resistance to lateral load and tensile strength for strain transducer, the protection sheath of strain transducer can be the metal tube of the cushion for surrounding the optical fiber for optionally buffering（Embodiment not shown in figure）.In this case, metal tube includes gel or gel-like material, and the gel or gel-like material optionally can provide under stress the mechanical fit sought between metal tube and the optical fiber that wherein includes.In a preferred embodiment, metal tube is formed from steel.

Preferably, in the group that the cushion of the fiber for only being coated by encirclement, protection sheath and strain transfer filler are constituted is made up of the material with plastic property.

Although in some preferred embodiments; strain transducer includes cushion to improve the intensity and elasticity of strain transducer; in construction as shown in Fig. 2 a and 2b; it is to be understood that; strain transducer can include being coated with the optical fiber of coat system, and the coat system is directly surrounded by protecting sheath.

Cable 1 preferably includes temperature sensor, and the temperature sensor includes the optical fiber 24 for measuring the internal temperature of cable 1.The optical fiber 24 of temperature sensor is in thin absorbing structure.Especially, in the embodiment shown in the drawings, optical fiber 24 is loosely placed on longitudinal direction and surrounds in the module 19 of fiber, and the module 19 is included in fibre optic element 3.Excessive optical fiber length of the module 19 of longitudinal extension comprising per unit length lightpipe optics fiber 24.Excess fibre length（EFL）Limited by following relation：

Its 1L_fIt is the length and L of optical fiber_tIt is the length of the pipe for accommodating fiber.Excess length is selected to cause optical fiber being applied to the maximum strain of cable（For example, 1%）It is lower to keep loose（Do not strain）.

The optical fiber 24 of temperature sensor is preferably single mode fibre and by using Brillouin backscattering commercial measurement temperature.It is envisaged, however, that multimode optical fiber is used for into temperature detection.In latter instance, temperature survey can be performed by using the known technology based on Raman scattering.Preferably, optical fiber 24 along the central longitudinal axis that cable extends relative to being spirally wound.For example, the coiling of optical fiber 24 longitudinal member.Including fibre optic element（The fibre optic element includes more than one optical fiber）Cable in the case of, two fibers can spiral wound each other along the longitudinal direction, in two fibers is used as the optical fiber of temperature sensor.Optical fiber 24 without mechanical stress only thermal expansion effects and can be used for temperature monitoring.When being strained by Brillouin backscattering commercial measurement, strain optical fiber is strained and temperature change affects.By the way that optical fiber 24 and strain optical fiber are optically coupled and by the temperature change in measurement optical fiber 24, temperature contribution can be deducted.

Whilst it is preferred that, also occurs the mechanical attachment between strain transducer and vertical structure element when cable is in the state that there is no 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, only can occur when at least one of vertical structure element is stretched load and becomes to be contacted with strain transfer filler.For example, there is mechanical attachment when vertical structure element undergoes the tensile load corresponding at least 0.1% prolongation.

Fig. 3 is the sectional view of cable according to other embodiments of the present invention.Identical reference is used for mark with the similar component with the same or similar function of the element of Fig. 1 b.Although the embodiment in Fig. 1 a and 1b also contacts the strain transfer filler of the vertical structure element of cable in the case of being included in without tensile load, but in the embodiment illustrated in figure 3, before installing or using in movable equipment, when state of the cable in there is no strain（For example, the initial condition of cable）When, strain transfer filler is not contacted（At least it is not fully）The surface of vertical structure element.Especially, cable 30 includes the strain transducer 5 surrounded by strain transfer filler 25, and the strain transfer filler is preferably directly extruded on strain transducer, for example, with reference to Fig. 2 a and 2b, is directly expressed on the outer surface of protection sheath 8.Strain transfer filler 25 can have circular cross section.For example, protect sheath 25 that there is 2 to 7mm thickness.Strain transfer filler 25 and radially outer vertical structure element（That is core 2 and earth conductor 7 and fibre optic element 3, if present）Between void space 26 can be with the identical material of the polymer filler 27 of besieged vertical structure element（For example, the compound based on EPR）Filling.

Because its size, the strain transducer 5 being buffered by strain transfer filler 25 is moved relatively freely in the void space 26 between strain transfer filler 26 and cable vertical structure element, and the mobility of strain transducer also depends on the viscosity of the material of filling void space.In the case where tension force is applied, vertical structure element tends to radially-inwardly compress, therefore is reduced to radial distance of the strain transducer along its longitudinal axis arranged.When the value of the tension force that cable is undergone is more than a certain threshold value, the contact with strain transfer filler 25 is radially-inwardly pressed and formed to vertical structure element.Conversely, when when cable extends in any lengthwise position of the length of cable in the case of less than that threshold value, the optical fiber of strain transducer 5 follows cable to move due to the clamping with the relative mistake of the vertical structure element of cable with certain delay.Preferably, the threshold value of tension force is 0.1%.

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

Fig. 4 is the sectional view of cable according to other embodiments of the present invention.Identical reference is used for mark with the similar component with the same or similar function of element of Fig. 1 a and 1b.Cable 40 includes the four vertical structure elements radially outward arranged relative to strain transducer 5, i.e., three electric power cores 43 and earth conductor 44, and four vertical structure elements can have the construction with reference to Fig. 2 a and 2b description.Electric power core 43 and earth conductor 44 include respectively the conductor 45 for example in the form of a branch of stranded tin plating or exposed copper electric wire surrounded by dielectric polymers 46.Strain transfer filler 47 embeds strain transducer 5 and fills the space between strain transducer and vertical structure element.The property and geometry of strain transfer filler 47 causes the mechanical attachment in the state without strain of cable（Especially mechanical fit）, exist between vertical structure element 43 and 44 and strain transducer 5.

Cable 40 can such as be used to vertically batch the 1kV power cables of application.In the embodiment that figure 4 illustrates, temperature sensor 48 is integrated in the region of vertical structure element inner radial, and especially in strain transfer filler 47.Temperature sensor 48 includes optical fiber 49, and the optical fiber is preferably single mode optical fibre, and in being loosely arranged in the module 41 of longitudinal extension, the module is preferably made up of ETFE or PBT.The external diameter of module 41 is such as 2mm.

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

Fig. 5 is the sectional view of cable according to other embodiments of the present invention.The cable for illustrating can be that the low-voltage for example for batching application controls cable.Cable 50 includes the multiple vertical structure elements being arranged in multiple concentric layers, and the plurality of concentric layer is around the center part 51 of strain transfer filler for serving as strain transducer 5.The vertical structure tray of elements of each concentric layer is around center part 51 and including control core 53 and a pair of the fibre optic elements 54 being arranged in most external concentric layer.Each control core 53 includes the fine rule copper conductor 59 surrounded by dielectric polymers 58.The form of module 52 of two fibre optic elements 54 in longitudinal extension, the module includes at least one optical fiber 57 being loosely arranged in the module（It is three optical fibers in figure）.The optical fiber of any bar of fibre optic element 54 can serve as temperature sensor.Polymeric inner sheath 55 surrounds the concentric layer of vertical structure element.With embedded stiffener（Such as polyester yarn fabric 35）External jacket 36 surround and internal jacket 55 and surround cable.

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

In the embodiment with reference to shown in Fig. 1 a-1b, 3,4 and 5, under strain regime, vertical structure element and the direct mechanical attachment of strain transfer filler of cable, i.e. there is mechanical fit between vertical structure element and strain transfer filler.Cable construction as a result enables the strain that the vertical structure element of such as core or earth conductor undergoes efficiently and quickly to be delivered to strain transducer.Fast reaction to strain variation allows the detection of the dynamic tension for for example occurring in the suddenly change of winding direction or the load/unload of movable equipment are moved.

It should be appreciated that when the cable of teaching of the invention originate from not with the part of the cable of strain transfer filler directly contact（Such as cable internal jacket or external jacket）When, also allow the detection for being strained.

Additionally, the present invention includes cable, the cable includes multiple vertical structure elements and the strain transducer being embedded in strain transfer filler, wherein at least one of vertical structure element and the direct mechanical attachment of strain transfer filler.

If the tension force of substantial constant is applied to a vertical structure element of cable during given interval, then the power determines and depends on and the frictional force between the intermediary element/layer of the vertical structure element mechanical attachment of strain and elasticity, integrated all vertical structure elements in the cable strain, for example with the strain of the element of the vertical structure element directly contact of strain, or across such as by other elements material detached with the element of strain（Such as polymer jacket）Carry out mechanical attachment.Contact area is bigger and element between frictional force it is bigger（Also depend on the value of tension force）, need the longitudinal length part of the cable with homogeneous strain shorter between vertical structure element.For for the heavy duty cables of movable equipment, with longitudinal length part necessary to the strain being distributed in whole piece cable cross-section five cable sizes, therefore typically no more than 20-40cm are about.The strain value worked in the different piece of cross section depends on the elastic property of constituent material.

Such as in dynamic strain measurement, in the case where the tension force that can be changed over to be applied to a vertical structure element of cable, in view of the strong adhesion between the frictional force between element, layer, and therefore constitute this layer material appropriate selection, the construction of cable becomes important.

Fig. 6 illustrates the schematic sectional view of the three-phase flat cable 60 of the application being such as used in well pump system, and the three-phase flat cable includes two external cores 61 and 63 and central core 62.The core is disposed substantially parallel to each other and adjacent, is centrally located along the common axis line 69a parallel to the X-direction being open into longitudinal cable axis.Axis 69a is plane（X,Y）In cable cross-section intermediate line.Optical fiber strain transducer 5 is arranged in of central core 62 and external core（It is in that case external core 61）Between.Strain transducer 5 can have the structure with reference to Fig. 2 a and 2b description.Strain transducer 5 is surrounded by strain transfer filler 66, and the strain transfer filler can have outer surface that is round-shaped and adhering to strain transducer.The radial thickness of strain transfer filler 66 is selected to depend on the side void space between side core 61 and central core 62 and to provide necessary mechanical resistance.Preferably, when cable is in the state that there is no strain, strain transfer filler is mechanically linked and especially mechanical fit with the outer surface of adjacent core 61 and 62.

The neutral axis of the bending of cable 60 is medial axis 69a, and the medial axis are the axis of symmetry of the cable cross-section along Y-axis line.Strain transducer 5 is arranged in the neutral region of the bending of the thickness d limited between two planes 69b, and the distance that two planes 69b leave 69a parallel to intermediate line 69a and along Y-axis line is d/2.For the ρ with 500mm_minRepresentative value flat cable, thickness d can vary to 10mm from 5.

Flat cable 60 also includes outer armor 68, and the outer armor is disposed relative in the external position of core and longitudinally surrounds them.Outer armor 68 has two relative lateral side 68b of a part for two external cores 61 and 63 of two substantially flat side 68a and encirclement parallel to X-axis line.Outer armor 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 limited by the space between core and outer armor 68.Strength member 67 is arranged in void space 65 in two common planes parallel to X-axis line.Strength member 67 has circular cross section and can be made up of the polymer of steel, glass or reinforcement.

Free space between core and strength member is filled with internal jacket 64, and the 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 using Brillouin backscattering technology（Such as, Brillouin optical time-domain reflectometer（BOTDR）, Brillouin Optical time-domain analyses instrument（BOTDA）With Brillouin Optical frequency domain reflectometer（BOFDR））, cable of the invention can be monitored to determine the strain along cable distribution.According to commonly known e measurement technology, the first optical signalling produced by first laser（Detector）Into the first end of the optical fiber of integrated strain transducer in the cable, and while, the second optical signalling produced by second laser or by identical first laser（Pump）Into the second end relative with first end of the optical fiber of strain transducer.First optical signalling operates continuously, is continuous wave（CW）Signal, and the second optical signalling is pulse.The measurement of optical signalling detected circuit is returned from the first end of optical fiber is backscattered.When the difference between the light frequency of CW optical signallings is more than the amount of a certain amount of Brillouin shift at certain some points being equal in the fibre than the difference of pulse optical signal, pulse signal is exaggerated by Brillouin's interaction and CW signals undergo loss.Brillouin shift is to strain and temperature sensitive.Brillouin backscattering technology has the advantages that for distribution sensing technology, this therefore real-time monitoring of permission along the actual strain profile of the length of cable.

By sample devicess, Brillouin scattering can be used for measurement simultaneously along the temperature of the length of the optical fiber of strain transducer and the change of strain, and the sample devicess map Brillouin spectrum to obtain temperature and strain information by scanning the frequency displacement of two lasing light emitters and being fitted Brillouin peak.By business type BOTDR equipment, such as by the business-like Foresigh of OZ Optics Ltd^TMSensor, can perform this analysis.In this applications, the temperature sensor in arrangement position detached with strain transducer in the cable is unnecessary for temperature sensing.

In some preferred embodiments, separation temperature contribution is contributed by the strain in the optical signalling from measurement, and by by the second optical fiber of loose absorbing structure be used for temperature survey, perform strain and temperature monitoring, as cable previous embodiment some described in.

Fig. 7 is the schematic block diagrams of the operating principle for illustrating monitoring system, and the monitoring system measures the strain in the length of cable and temperature change using the backscatter technique based on Brillouin of such as BOTDR.Sample devicess 70 are used to optical signalling is introduced in cable 73 and is analyzed from the backscattered optical signalling of cable reception.For example, sample devicess can be by the business-like DITEST-DSM systems of Omnisens SA.Cable includes strain transducer, and the strain transducer includes optical fiber 71 and the temperature extended along cable longitudinal direction Z（Sensor）Optical fiber 72（Strain and temperature fiber are diagrammatically only shown in figure）.Including the strain transducer of strain optical fiber 71 at least one vertical structure element of cable 73 is mechanically coupled to allow strain to be delivered to strain transducer from least one vertical structure element, and the optical fiber 72 for being used for temperature sensing is integrated in the cable with loose construction.Cable 73, and particularly arrangement of the optical fiber 71 and 72 in cable, can have described in the previous embodiment structure any structure structure.Strain optical fiber 71 is located in the longitudinal direction neutrality bending area of cable and has mechanical fit with least one vertical structure element of cable, and temperature optical fiber 72 is arranged to not affected by the strain for being applied to cable with loose absorbing structure.Sample devicess 70 launch pumping optical signalling to the cable portion 74 of the close end for being connected to strain optical fiber 71 from the first output 78.Meanwhile, detector optical signalling is transmitted in the cable portion 75 for being connected to the close end of temperature optical fiber 72 from the second light output 79.Term " near " and " remote " for fiber end is, relative to sample devicess, or to be at least connected relative to the optics with sample devicess.However, this term is merely intended to indicate relative position and/or the description for facilitating accompanying drawing, but they are not construed as with absolute sense.The cable section 74 and 75 of measuring apparatus 70 can be formed to the impermanent connection between corresponding optical fiber 71 and 72 by conventional equipment, such as by optical conenctor 77.In strain and temperature optical fiber 71 and 72 at least one, and preferably two fibers, the length with the close end and distal portion for extending beyond cable 73.In the end of the optical fiber of close sample devicess 70, the connection of the equipment is this simplifies.The distal portion relative with close end of the optical fiber projected from cable is connected to each other to produce fibrous ring, and the fibrous ring is in the only one end of cable（That is, close end）With two input/output ends.In remote end part, according to conventional methods by welding in jointer 76, two fibers can link together.

Brillouin backscattered light signal leaves temperature sensor fiber 72, into sample devicess 70 and can be processed to determine strain along cable and temperature change.Include straining the fibrous ring of optical fiber 71 and temperature fiber 72 by consideration, the strain of measurement and temperature are along fibrous ring（And therefore in two sense fiber each）The position of positioning can downwards be propagated by pulse and transition time for being returned by fibrous ring is determining.

Optical fiber ring can be by using known technology（Such as by using OTDR technique）Be calibrated, so as to know adapter position and/or fibrous ring in optics connection, and it is thus determined that position and length in fibrous ring of temperature and strain optical fiber.

Strain optical fiber 71 is strained and temperature change affects, and the only temperature influence of temperature optical fiber 72 with loose construction in the construction of cable.By deducting the temperature contribution along the annulus fibrosus portion corresponding to integrated optical fiber 72 in the cable, it may be determined that the contribution to Brillouin shift for only being caused by strain.

In embodiment, mirror can be disposed relative to the remote end part of the temperature optical fiber of sample devicess, and pump and detector optical signalling are launched in the close end of temperature optical fiber.This scheme（Not shown in figure）The fibrous ring between strain and temperature optical fiber for measuring need not be used for.

Strain the strain in optical fiber and can be determined using strain calibrating installation by maker including the correlation between the strain in the cable of strain optical fiber, the longitudinal direction prolongation of known quantity can be applied to cable by the strain calibrating installation.By Brillouin scattering technology, according to the cable in resting position and the prolongation for being subjected to known quantity, the prolongation in analyzing optical fiber to determine fiber.For example, when cable is subjected to uniform and " static state " to be extended, 0.75% (Δ L/L)_fibreCorresponding to 1% (Δ L/L)_cable, represent that 75% strain is delivered to fiber from cable.

Applicant have observed that, the cost of Brillouin's sample devicess（Especially if necessary to wide scope high-sensitivity measurement）It is relatively high, and therefore would be advantageous to provide the monitoring system of a plurality of cable to reduce totle drilling cost.

The applicant has also been noted that the real-time monitoring of heavy duty cables by the dynamic event for allowing record to cause elastic strain peak, and the dynamic event can pass through fatigue damage cable.

Fig. 8 is the region for goods movement（Container terminal in such as harbour）In a plurality of heavy duty cables monitoring system schematic diagram.Container terminal is the port facilities in the region for generally covering big, across the port facilities, container（Not shown in figure）It is stored to be loaded onto ship or to collect from harbour.Multiple heavy duty cranes 82 across the selection area movement of harbour to lift and shift container, while being supplied electric power from power transmission station 81 and being controlled.Heavy duty crane 82 can be integrally fixed at the gantry on a pair of rails 90a and 90b, and a pair of rails are arranged on the port area behind harbour（The port area is represented in figure with hatched area 91）On, wherein quay crane is used to loading and unloading ship operation.Container（It is not shown）In space of the number row's stacking between in-orbit, there can be lifted by gantry and be moved back and forth, the gantry is flatly moved back and forth along the direction that double-head arrow 92 is indicated.Fig. 9 is the side view of the multiple gantries for for example obtaining along the line C-C of Fig. 8.The supporting construction of gantry 82 includes the bridgeware with two elevated rails 93a and 93b（It is invisible in fig .9）, winch truck 83 moves on the bridgeware perpendicular to the motion of crane.According to conventional design, winch truck 83 has the capstan system for lifting container（It is not shown）.

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

Each gantry 82 provides electric power by corresponding cable 86, and the cable can be conventional power cable, and power transmission station 81 is connected to into crane feeding unit 89.Heavy duty cables 85 are connected to crane feeding unit 89 to obtain electric power and for the several functions of crane 82 from the crane feeding unit that carried by corresponding cable 86（Its movement, positioning, monitoring etc.）Electric power is provided.Additionally, heavy duty cables receive control/datagram number and/or optical signalling.Although crane feeding unit is shown as being disposed close to the vicinity of the rail end at power transmission station, the other positions of crane feeding unit be it is possible, such as the length relative to rail rail side middle position.

Heavy duty cables 85 are fastened the spool 84 on the cross side of crane structure.Cables reel 84 can be motorized to allow spool to rotate along both direction.Cable to the guiding of crane feeding unit can be by guide 96（It is visible in Fig. 9）There is provided, in the embodiment of the figure, the guide includes two deflection guide reels arranged laterally opposedly.One end of each cable 85 is fixed in corresponding crane power supply unit 89 and relative end is typically at the center of cable reel（Referred to as backbone）It is fixed at cables reel 84.During rapidly the moving horizontally of crane, when the cable around spool discontinuous and usual unexpected winding and the unwinding stage occur when, heavy duty cables 85 are subsequent restrained two ends.Generally, the acceleration of crane and slowing down synchronously does not occur with the winding of cable or unwinding, therefore applies the peak value for repeating in the prolongation of cable.

In embodiment, heavy duty cables have the structure of the type with reference to Fig. 1 a and 1b description.In another embodiment, heavy duty cables have any one of the structure with reference to the description of Fig. 1 a-1b, 3,4 and 5.

Fig. 8 and 9 is referred again to, each heavy duty cables 85 include strain transducer and temperature sensor.Strain transducer includes the optical fiber of at least one vertical structure element for being mechanically coupled to cable, especially with the matched optical fiber of at least one vertical structure element of cable machinery, and temperature sensor includes the optical fiber being integrated in loose construction in cable.The optical fiber of at least 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.

Electric power is transported to into each powered in cable 86 of heavy duty cables 85 includes integrated fibre optic element, and the integrated fibre optic element is included preferably with loose absorbing structure along at least two optical fibers for supplying cable arrangement.One end of each optical fiber in supply cable 86 is optically connected to Brillouin's sample devicess（Not shown in Fig. 8 and 9）, and relative end is optically connected to the corresponding end of strain that heavy duty cables 84 include and temperature optical fiber.Optics connection can occur by conventional equipment in power subsystem.Therefore, heavy duty cables 85 are enable to receive electric power and the optical signalling for Brillouin's analysis from corresponding supply cable 86.Brillouin's sample devicess may be accommodated in power transmission station 81.In figs. 8 and 9, for the sake of just to understanding, supply cable 86 is shown above the ground.It should be appreciated that supply cable can reach crane power supply unit extend in subsurface simultaneously（Described by dotted line in fig .9）.

Figure 10 is schematic diagram, illustrates the operating principle of the monitoring system for straining and being preferably used for controlling its temperature of a plurality of heavy duty cables for control on movable equipment according to embodiment.A plurality of supply cable 103,105,107 and 109 respectively includes the first and second supply optical fiber 118a and 118b, 119a and 119b, 120a and 120b and 121a and 121b.The supply supply electric power of cable 103,105,107 and 109, and preferably supply control signal arrives corresponding heavy duty cables 104,106,108 and 110, and each heavy duty cables include strain transducer optical fiber 112a and temperature sensor optical fiber 112b.First supply optical fiber 118a, 119a, 120a and 121a is optically connected to the strain optical fiber 112a of corresponding heavy duty cables 104,106,108 and 110.Second supply optical fiber 118b, 119b, 120b and 121b is optically connected to the temperature optical fiber 112b of corresponding heavy duty cables 104,106,108 and 110.The supply optical fiber of supply cable is connected and can be implemented by welding with the strain of heavy duty cables and the optics of temperature optical fiber.It is connected to each other relative to the remotely located strain of each heavy duty cables of corresponding supply cable and the end of temperature optical fiber 112a and 112b（Represented by the junction point of device, for example jointer 113）To form the fibrous ring across heavy duty cables and supply cable.In the embodiment for illustrating in figs. 8 and 9, the distal site of strain and temperature optical fiber is in being bonded in the spool of crane（For example in the backbone of spool）Heavy duty cables end.

Brillouin's sample devicess 100 send the first optical signalling from input/output optical port 101（Pump）And send the second optical signalling from input/output optical port 102（Detector）.Signal is launched in corresponding first and second optical fibers part 111 and 114 from input/output optical port 101 and 102.First optical fiber part 111 is optically connected to receive the first supply optical fiber 118a of the supply cable 103 of pump signal, and the second optical fiber part 114 is optically connected to the second supply optical fiber 121b for being finally fed cable 109 of pick-up probe signal.Second supply fiber 118b of the first supply cable 103 is optically connected to the first supply fiber 119a of the second supply cable 104；Second supply fiber 119b of the second supply cable 104 is optically connected to the first supply fiber 120a of the 3rd supply cable 105, and the second supply fiber 120b of the 3rd supply cable 105 is optically connected to the first supply fiber 121a of the second supply cable 107.This produces fibrous ring, and the fibrous ring has an end of the second supply fiber 121b of an end and the 4th supply cable 109 of the first supply fiber 118a near the first supply cable 103 as the light input/output opened（Close end）.Refer to the attached drawing, term " near " and " remote " are construed as reference sample equipment, or at least with reference to being connected with the optics of sample devicess.However, this term is merely intended to indicate relative position and/or for convenient description, but they are not construed as with absolute sense.One end of the optical fiber end of two different supply cables or the optical fiber of supply cable couples with the light of the fiber part for being optically connected to sample devicess can be implemented by conventional coupling arrangement, and the conventional coupling arrangement is no to be illustrated in figure.

The quantity for being connected to the heavy duty cables of the Brillouin's sample devicess illustrated in Figure 10 is 4.It will be appreciated, however, that compared with Brillouin's instrument dynamic, light loss, welding loss, the mechanical engagement loss caused depending on fiber decay and fibre length, the quantity can be different.For example, the heavy duty cables for reaching 10 in corresponding crane can be measured in single fibrous ring.

Supply optical fiber is preferably carrier class single mode optical fibre.

First and second optical signallings be for produce Brillouin backscatter signal with suitable amplitude and the counter propagating optical signal of frequency, the Brillouin backscatter signal is sampled equipment 100 and analyzes.The fibre length of the fiber in by understanding supply cable and in the heavy duty cables of formation fibrous ring（For example, after the calibration of the Wiring structure in ring）, strain variation can be associated with along the position of fibrous ring, and therefore monitoring is applied to the strain of each heavy duty cables for being optically connected to sample devicess.

According to an aspect of the present invention, for monitoring a plurality of cable（And in particular for monitoring a plurality of heavy duty cables）Monitoring system include：For measuring the sample devicess of the spectrum change of Brillouin scattering, the sample devicess include 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 a plurality of heavy duty cables, the a plurality of heavy duty cables include first and last heavy duty cables, each cable in a plurality of cable includes strain transducer and temperature sensor, the strain transducer includes strain optical fiber, the temperature sensor includes temperature optical fiber, and, along corresponding cable longitudinal extension, the strain optical fiber and temperature optical fiber have close end and distal portion for the strain and temperature sensor, the close end is arranged in the close end of corresponding cable, wherein：The strain optical fiber of each heavy duty cables and the optics connection each other of the distal portion of temperature optical fiber, the close end of the strain optical fiber of the first heavy duty cables and the first input/output optic communication of sample devicess and the second input/output end port optic communication of the temperature optical fiber of last cable and sample devicess, and the close end of the temperature optical fiber of the first heavy duty cables is connected with the close end optics of the strain optical fiber of last heavy duty cables, to form optical fiber ring, in the optical fiber ring, the strain optical fiber and temperature optical fiber of each heavy duty cables of a plurality of heavy duty cables and the first and second input/output end port optic communications of sample devicess, and the first and second optical signallings enter in opposite direction optical fiber ring.

Applicant have observed that, commercially available Brillouin's sample devicess can measure strain and the temperature of the optical fiber for reaching 20km.When crane dispersion on large regions and along the direct of travel perpendicular to crane horizontal direction be spaced apart it is sizable apart from when, it may not be especially efficient crane significantly spaced apart to be connected to and accommodates the identical power transmission station shell of sample devicess.In addition, it would be advantageous to, use the typically pre-existing Wiring structure from power transmission station to crane.

Figure 11 illustrates the region for goods movement according to other embodiments of the present invention（Container terminal in such as harbour）In a plurality of heavy duty cables monitoring system.Identical reference is used for mark with the similar component with the same or similar function of the element of Fig. 8.Electric power and control signal are supplied to first group of crane 130 in power transmission station 125, and the supply electric power of power transmission station 128 and control signal are to second group of crane 131.Any one of power transmission station accommodates Brillouin's sample devicess（It is not shown）, the sample devicess are optically connected to one in the supply cable at other power transmission stations by optical cable 129, and the optical cable includes two optical fibers of preferably single mode optical fibre.The quantity of the crane in each group is entirely exemplary, although the quantity can typically from 3 to 6 changes.

The possible optical configuration of the monitoring system of Figure 11 is illustrated in the schematic diagram of Figure 12.First group of supply cable 145,149,150 and 152 includes respectively the first and second supply optical fibers, and the first and second supplies optical fiber passes through known method（Such as pass through optical conenctor 167）It is optically connected to corresponding strain and the temperature optical fiber of corresponding heavy duty cables 146,147,148 and 151.First group of supply cable receives electric power from the first power transmission station.Second group of supply cable 158,159 and 160 includes respectively the first and second supply optical fibers, and the first and second supplies optical fiber is optically connected to the corresponding strain optical fiber and temperature optical fiber of corresponding heavy duty cables 155,156 and 157.Second group of supply cable is from the second power transmission station（Not shown in Figure 12）Receive electric power.Two light input/output end ports 163 and 164 of Brillouin's sample devicess 143 are optically 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 devicess 143 and photoswitch 140 can be for example accommodated in the first power transmission station 125.Photoswitch 140 tends to separate and be directed to two input/output end ports 141 and 161 by the first optical signalling for receiving, and separates and be directed to two input/output end ports 142 and 162 by the second optical signalling for receiving.Photoswitch 140 can be general type, such as single mode fibre 1x2 or 1x4 or 1x8 photoswitches.

The optics connection each other of the strain of first group of each heavy duty cables and the distal portion of temperature optical fiber（For example pass through adapter 113）To form the first fibrous ring, first fibrous ring has the end of the second supply fiber as the end of the first supply fiber of the first the first supply cable 145 for opening end and as the second the 4th supply cable 152 for opening end.The input/output end port 141 of photoswitch is optically connected to the close end of the first fiber optics of the first supply cable 145 by fiber part 111, and the input/output end port 142 of photoswitch is optically connected to the 4th by fiber part 114（Finally）The close end of the second fiber optics of supply cable 152.

From the first optical signalling that output port 141 sends（Pump）In being launched into the first supply fiber of supply cable 145, and the second optical signalling（Detector）In being launched into the second optical fiber of supply cable 152.First optical signalling enters a supply fiber of first group of the first supply cable 145, advances along fibrous ring, i.e., it is propagated along first group of supply and all fibres of heavy duty cables, and from the fiber for being finally fed cable 152 out.The second optical signalling sent from input/output end port 142 is advanced in opposite direction relative to the first optical signalling back propagation along fibrous ring.The Brillouin backscatter signal for leaving the second optical fiber of supply cable 152 is analyzed into photoswitch 140 and by sample devicess 143.

Similarly, each other optics connects to form the second fibrous ring the distal portion of each of second group of heavy duty cables 155,156 and 157, second fibrous ring has the optical tip of two openings, that is, supply the first optical fiber of cable 158 and the second optical fiber of supply cable 160.In the fibrous ring, the close end of the second optical fiber of the first supply cable 158 is connected with the first optical fiber optics of the second supply cable 159, and similarly, the close end of the second optical fiber of the second supply cable 159 is connected with the first optical fiber optics of the 3rd supply cable 160.The input/output end port 161 and 162 of photoswitch 140 is optically connected to connect the corresponding first and second connections optical fiber of optical cable 144, and the optical cable has near the first end of photoswitch 140 and relative to the remotely located the second end of photoswitch.In the distal portion relative with close end of optical cable 144, the first and second connection optical fibers are optically connected to supply the second optical fiber of the first optical fiber of cable 158 and supply cable 160.So, second group of heavy duty cables receives two sample optical signals from connection optical cable 144, wherein the optical signalling sent from equipment 143 guides to connection optical cable 144 into photoswitch 140 and by photoswitch 140.The Brillouin backscatter signal produced in second group of heavy duty cables is fed back in connection optical cable 144 and by photoswitch 140 and guides to input/output end port 165 and 166, hence into sample devicess 143.

Advantageously allow for further reducing the cost of monitoring system with reference to the embodiment of the descriptions of Figure 11 and 12.

Although in the aforementioned embodiment, supply cable is described as being provided with the fiber optic component including at least two optical fibers, 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, the supply wiring system includes power supply cable and optical cable, and the optical cable includes at least two optical fibers.It that case, optical cable can extend and be optically connected to strain and the temperature optical fiber of heavy duty cables beside power supply cable.

Present invention could apply to monitoring system, in the monitoring system, sample devicess are directly optically connected to a plurality of heavy duty cables, and a plurality of heavy duty cables are provided with optical fiber strain transducer, and are preferably provided with optical fiber temperature sensor.In other words, generally, the fibrous ring of monitoring system need not include supply cable as the intervening power/control power supply component for heavy duty cables, especially in a plurality of cable to be monitored not across big region（Such as port container terminal）In the case of distribution.

Claims (12)

1. a kind of deformation monitoring side at least measuring the elongation strain of at least one cable Method, the method comprising the steps of：

At least one cable is provided, at least one cable includes：Strain transducer (5), The strain transducer is along the cable longitudinal extension and including being arranged in bending neutral region Interior single mode strain optical fiber (9), the bending neutral region is surrounded and including described The bending neutrality longitudinal axis (Z of cable；69a)；With at least two vertical structure elements (2,7, 3；43,44；53,54；61,62,63), at least one of described at least two vertical structures element It is to include electric conductor (12；45；59) core (2；43；53), wherein the strain transducer extremely It is mechanical with least one of at least two vertical structures element in strain regime less to join Connect and mechanical fit；

First optical signalling is introduced into the strain optical fiber；

Detect the Brillouin scattering sent from the strain optical fiber；With

The spectrum change in the scattered light is analyzed, at least to measure at least one cable Elongation strain.

2. method according to claim 1, wherein, at least one cable is also wrapped Include the temperature optical fiber (24 for temperature sensing；49；57), the temperature optical fiber edge The module that the length of the cable extends and is encapsulated in longitudinal extension with loose construction (19；41；52) in, and the temperature optical fiber is optically connected to the strain optics Fiber, methods described is further comprising the steps of：Along contrary relative to first optical signalling The direction of propagation the second optical signalling is introduced into the temperature optical fiber.

3. a kind of deformation at least measuring the elongation strain of at least one cable monitors system System, the deformation monitoring system includes：

Cable, the cable includes：Strain transducer, the strain transducer is along the cable Longitudinal extension and including single mode strain optical fiber, the strain optical fiber have arrangement Close end and distal portion in bending neutral region, the bending neutral region surround and Including the bending neutrality longitudinal axis of the cable；With at least two vertical structure elements, institute It is the core for including electric conductor to state at least one of at least two vertical structure elements, wherein institute State strain transducer at least in strain regime with least two vertical structures element in At least one mechanical attachment and mechanical fit；With

Sample devicess, the sample devicess are used to measure the Brillouin in the strain optical fiber The spectrum change of scattered light, the sample devicess are at least described with the strain optical fiber Close end optics couples, to introduce light into the strain optical fiber.

4. a kind of deformation monitoring system at least measuring the elongation strain of a plurality of cable, institute Stating deformation monitoring system includes：

For measuring the sample devicess of the spectrum change of Brillouin scattering, the sample devicess bag Include the first optical input/output port and the second optical input/output port, first optics Input/output end port is used to send the first optical signalling and the second optics input/output Port is used to send the second optical signalling；With

First group of a plurality of cable, first group of a plurality of cable includes the first cable and last electricity Cable, each cable in first group of a plurality of cable includes that strain transducer and temperature are passed Sensor, the strain transducer includes strain optical fiber, and the temperature sensor includes temperature Degree optical fiber, the strain transducer and temperature sensor along corresponding cable longitudinal extension, The strain optical fiber and temperature optical fiber have close end and distal portion, the strain The close end of optical fiber and the close end of temperature optical fiber are located at the near-end of corresponding cable At portion, wherein：

The distal portion and the temperature optical fiber of the strain optical fiber of each cable Distal portion each other optics connection,

The first cable in first group of a plurality of cable strain optical fiber close end with First optical input/output port optic communication of the sample devicess, and it is described more than first group The temperature optical fiber of the last cable in bar cable is defeated with the second optics of the sample devicess Enter/output port optic communication, and

The strain of the close end of the temperature optical fiber of first cable and the last cable The close end optics connection of optical fiber, it is fine in the optics to form optical fiber ring In dimension ring, the strain optical fiber of each cable in a plurality of cable and described First optical input/output port and the second optics of temperature optical fiber and the sample devicess The optic communication of both input/output end ports, and first optical signalling and the second optical signalling The optical fiber ring is entered in opposite direction.

5. system according to claim 4, wherein, in first group of a plurality of cable Each cable be the heavy duty cables for including at least two vertical structure elements, it is described at least At least one of two vertical structure elements are the cores for including electric conductor, each heavy cable The strain optical fiber of line is arranged in bending neutral region, and the bending neutral region is surrounded And including the bending neutrality longitudinal axis of the cable, and

Wherein, at least in the strain transducer and at least two vertical structures element Individual mechanical attachment.

6. system according to claim 5, wherein, each heavy duty cables it is described Strain transducer is embedded in strain transfer filler, and the strain transfer filler is at least two by described in At least one of individual vertical structure element and the strain transducer mechanical attachment so that extremely It is few in strain regime, at least one of at least two vertical structures element undergoes Strain is passed to the strain transducer.

7. the system according to any one of claim 4 to 6, wherein, described The temperature sensor of each cable in one group of a plurality of cable extends along the length of the cable And it is encapsulated in the element of longitudinal extension with loose construction.

8. system according to claim 6, wherein, the institute in each heavy duty cables Stating strain transducer includes surrounding the protection sheath of the strain optical fiber, and wherein institute State strain transfer filler to surround the protection sheath and protect sheath fit with described.

9. the system according to any one of claim 4 to 6, also including first group A plurality of supply cable, first group of a plurality of supply cable is including the first supply cable and finally Supply cable, each supply cable in a plurality of supply cable is optically connected to described Respective cable in first group of a plurality of cable, the first supply cable and first cable Optics connects and the cable that is finally fed is connected with the last cable optic, wherein：

Each supply cable in first group of a plurality of supply cable includes the first supply light Learn fiber and the second supply optical fiber, the first supply optical fiber and the second supply light Learning fiber includes respectively close end and distal portion,

The distal portion of the distal portion of the first supply optical fiber and the second supply optical fiber The strain optical fiber and temperature optical fiber of respective cable are optically connected to respectively, and And

By by described first supply cable first supply optical fiber close end with it is described The first optical input/output port connection of sample devicess, and by being finally fed described Cable second supply optical fiber close end and the measuring apparatus the second optics input/ Output port connects, and the of strain optical fiber and the sample devicess of first cable One optical input/output port optic communication.

10. system according to claim 9, wherein, first group of a plurality of supply cable Each supply cable in line is cable, and the first supply optical fiber and second is supplied Optical fiber is integrated in the cable with loose construction, and optics connection is occurring On the end of heavy duty cables, each supply cable is electrically connected to corresponding heavy duty cables.

11. systems according to any one of claim 4 to 6, wherein, described Each cable in one group of a plurality of cable is arranged on corresponding movable equipment.

12. systems according to claim 11, wherein, the movable equipment has been Heavy-duty machine, the crane includes supporting construction and is rotatably mounted to the support Spool in structure, the respective cable can be wound on said reel and from the spool Upper unwinding, the respective cable is engaged on said reel in its distal portion.