Submarine cable and sensing assembly therefor

Abstract

The application provides a submarine cable and a sensing assembly thereof, and relates to the technical field of ocean engineering. The sensing assembly comprises a sensing optical cable and a plurality of coupling members. The sensing optical cable is placed in a receiving groove of the submarine cable, and a plurality of first sensing units and a plurality of second sensing units are arranged on the sensing optical cable. The first sensing units are used for acquiring temperature information of the submarine cable, and the second sensing units are used for acquiring strain and temperature information of the submarine cable. The coupling members are sleeved on the outside of the sensing optical cable. The second sensing units are arranged between two adjacent coupling members. The coupling members comprise a body part and at least one limiting part. The inner side of the body part is provided with an anchoring part, and the rigidity of the anchoring part is greater than that of the body part. The first sensing units are located on the inner side of the anchoring part. The limiting part is in abutting contact with the inner wall of the receiving groove when the submarine cable is bent, so that the body part deforms with the submarine cable. The sensing assembly provided by the application can realize self-compensation of temperature and high-precision measurement of deformation of the submarine cable at the same time without increasing the diameter of the sensing optical cable.

Description

Technical Field

[0001] This application relates to the fields of fiber optic sensing and marine engineering technology, and in particular to a submarine cable and its sensing components. Background Technology

[0002] Dynamic submarine cables withstand alternating loads from waves and ocean currents over long periods, making structural health monitoring crucial for ensuring the safe operation of marine equipment. Fiber optic sensing technology, due to its advantages such as interference resistance and corrosion resistance, is widely used in submarine cable monitoring. The sensing cable contains fiber optic gratings as sensing units, which can respond to changes in external temperature and strain.

[0003] Because fiber Bragg gratings are sensitive to both temperature and strain, separate deformation-sensing and temperature-sensing optical cables are typically required in monitoring applications. The deformation-sensing cable acquires a mixed signal containing both temperature and strain information. Its outer diameter is matched to the cable's overall dimensions to ensure consistent strain with the cable body, guaranteeing measurement accuracy. The temperature-sensing cable acquires temperature information separately and compensates for the mixed signal from the deformation-sensing cable, thus calculating the pure strain distribution.

[0004] However, submarine cables have limited internal space, and laying two types of sensing optical cables at the same time would lead to a complex structure, require more fiber optic channels, and increase manufacturing costs. Summary of the Invention

[0005] In view of the above problems, this application provides a submarine cable and its sensing component. The sensing component can simultaneously achieve temperature self-compensation and high-precision measurement of submarine cable deformation without increasing the diameter of the sensing optical cable.

[0006] To achieve the above objectives, the embodiments of this application provide the following technical solutions:

[0007] One aspect of this application provides a sensing component for a submarine cable, comprising: a sensing optical cable for placement in a receiving groove of the submarine cable, wherein a plurality of first sensing units and a plurality of second sensing units are disposed on the sensing optical cable, the first sensing units are used to acquire temperature information of the submarine cable, and the second sensing units are used to acquire strain and temperature information of the submarine cable; the plurality of first sensing units and the plurality of second sensing units are alternately spaced along the axial direction of the sensing optical cable.

[0008] Multiple coupling elements are configured to form a through-hole with openings at both ends, so that the coupling element is fitted onto the outside of the sensing optical cable; a second sensing unit is disposed between two adjacent coupling elements;

[0009] The coupling member includes a body and at least one limiting part; the limiting part is disposed at the axial end of the body, and a through channel passes through the body and the limiting part axially.

[0010] An anchoring part is provided on the inner side of the main body, and the stiffness of the anchoring part is greater than that of the main body; the inner side of the anchoring part is constructed to form a through-channel; each first sensing unit is located on the inner side of the anchoring part within one of the coupling members.

[0011] The outer peripheral edge of the limiting part protrudes beyond the outer peripheral edge of the main body; the limiting part is configured to abut against the inner wall of the receiving groove when the submarine cable bends, so that the main body deforms with the submarine cable.

[0012] In one possible implementation, an anchoring medium layer is provided between the anchoring part and the sensing optical cable.

[0013] In one possible implementation, the body includes a bearing sleeve connected to a limiting part, and an anchoring part disposed inside the bearing sleeve.

[0014] In one possible implementation, the outer wall of the bearing sleeve is constructed to form a spiral groove.

[0015] In one possible implementation, the body portion further includes a flexible interface layer located at both ends of the anchor portion along the axial direction and between the sensing optical cable and the carrier sleeve, for providing support for the sensing optical cable when the coupling element bends.

[0016] In one possible implementation, the body further includes a stress buffer layer located inside the bearing sleeve; the radial elastic modulus of the stress buffer layer is greater than its axial elastic modulus; the stress buffer layer is used to absorb the shear energy generated by the relative displacement between the bearing sleeve and the flexible interface layer.

[0017] The stress buffer layer includes a first part and a second part. The first part is located between the bearing sleeve and the anchoring part; the second part is located between the bearing sleeve and the flexible interface layer, and at both ends of the anchoring part.

[0018] In one possible implementation, the outer periphery of the limiting portion is adapted to the cross-sectional shape of the receiving groove.

[0019] In one possible implementation, the coupling member includes a first coupling portion and a second coupling portion, the first coupling portion including a first body, and the second coupling portion including a second body; the first body and the second body enclose each other to form a through-channel.

[0020] At least one of the first coupling portion and the second coupling portion has a limiting portion at its end.

[0021] In one possible implementation, the sensing optical cable includes:

[0022] Central optical fiber;

[0023] Multiple peripheral optical fibers are distributed circumferentially around the central optical fiber.

[0024] Multiple support units are distributed circumferentially around the central optical fiber and are alternately arranged with the outer optical fibers;

[0025] The first sensing unit is located in the central optical fiber, and the second sensing unit is located in the peripheral optical fiber.

[0026] Another aspect of this application provides a submarine cable, comprising:

[0027] The sensing component as described above; the submarine cable body, which includes a cable core, a support sleeve, and an outer sheath; the support sleeve is disposed on the outside of the cable core, and the support sleeve is constructed to form an axially extending receiving groove; the sensing component is disposed in the receiving groove; and the outer sheath covers the outside of the support sleeve and the cable core.

[0028] This application provides a submarine cable and its sensing component. The sensing component includes a sensing optical cable and multiple coupling elements. The sensing optical cable is placed within a receiving slot of the submarine cable. Multiple first sensing units and multiple second sensing units are disposed on the sensing optical cable. The first sensing units are used to acquire temperature information of the submarine cable, and the second sensing units are used to acquire strain and temperature information of the submarine cable. The multiple first sensing units and multiple second sensing units are alternately spaced along the axial direction of the sensing optical cable. Integrating the first and second sensing units into the same sensing optical cable simplifies the internal structure of the submarine cable and reduces the occupation of optical fiber channels.

[0029] The coupling element is constructed to form a through-hole with openings at both ends, allowing it to be fitted over the outside of the sensing optical cable. A second sensing unit is positioned between two adjacent coupling elements. The coupling element can transmit the deformation of the submarine cable to the sensing optical cable.

[0030] The coupling element includes a body and at least one limiting part. The limiting part is located at the axial end of the body, and a through-channel passes through the body and the limiting part axially. An anchoring part is provided on the inner side of the body, and the inner structure of the anchoring part forms part of the through-channel. Each first sensing unit is located inside the anchoring part in one of the coupling elements, and the stiffness of the anchoring part is greater than that of the body. The anchoring part can be used to form a rigid constraint on the section of the sensing optical cable corresponding to the first sensing unit, so that the sensing optical cable in that section does not generate axial strain during the deformation of the submarine cable, thereby ensuring that the first sensing unit only responds to the temperature of the submarine cable, and its output signal can be used as a pure temperature reference to perform temperature compensation on the output signal of the second sensing unit, separating the pure strain information generated by the deformation of the submarine cable.

[0031] A limiting part is located at the end of the main body, with its outer peripheral edge protruding beyond the outer peripheral edge of the main body. When the submarine cable is in a free state, the limiting part remains in contact with the inner wall of the receiving groove. When the submarine cable bends, the receiving groove deforms along with the cable, and the limiting part forms abutment contact with the inner wall of the receiving groove. The coupling member can transmit the deformation of the submarine cable to the main body through the limiting part, causing the main body to bend synchronously with the submarine cable.

[0032] Therefore, the sensing component of this application can simultaneously achieve high-precision measurement of temperature self-compensation and submarine cable deformation through a single sensing optical cable, thereby simplifying the internal structure of the submarine cable and avoiding the problem of deterioration in bending performance caused by thickening of the sensing optical cable. Attached Figure Description

[0033] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0034] Figure 1 This is a schematic diagram of the structure of a submarine cable provided in an embodiment of this application;

[0035] Figure 2 A cross-sectional structural diagram of the coupling element in the sensing component provided in the embodiment of this application when it is assembled on the outside of the sensing optical cable;

[0036] Figure 3 This is a schematic diagram of the coupling element in the sensing component provided in the embodiments of this application;

[0037] Figure 4 This is a schematic diagram of the structure of the first coupling part or the second coupling part in the sensing component provided in the embodiments of this application.

[0038] Explanation of reference numerals in the attached figures:

[0039] 1-Submarine cable;

[0040] 10 - Sensing components; 20 - Submarine cable body;

[0041] 100 - Sensing optical cable; 200 - First sensing unit; 300 - Second sensing unit; 400 - Coupler; 400a - First coupling part; 400b - Second coupling part; 400c - Through-passage channel;

[0042] 110 - Central optical fiber; 120 - Peripheral optical fiber; 130 - Support unit; 410 - Body; 420 - Limiting part; 430 - Anchoring part;

[0043] 411-Bearing sleeve; 412-Flexible interface layer; 413-Stress buffer layer;

[0044] 4111 - Spiral groove; 4131 - First part; 4132 - Second part;

[0045] 21-Cable core; 22-Support sleeve; 22a-Receiving groove; 23-Outer sheath. Detailed Implementation

[0046] As described in the background section, dynamic submarine cables, as core components of marine equipment such as floating production platforms and offshore wind farms, are subjected to alternating loads generated by waves, ocean currents, and platform movement over long periods of time. Monitoring their structural integrity is crucial for ensuring the safe operation of the equipment.

[0047] Fiber optic sensing technology is widely used in the structural health monitoring of dynamic submarine cables due to its advantages such as resistance to electromagnetic interference, corrosion resistance, and distributed measurement capabilities. As a specific application of fiber optic sensing technology in engineering, sensing optical cables contain fiber optic gratings (FGGs). These FGGs, acting as sensing units, respond to changes in external temperature and strain, reflecting the measured information through wavelength shift.

[0048] Because fiber Bragg gratings exhibit cross-sensitivity to temperature and strain, their output wavelength drift simultaneously contains both temperature and deformation information, which are coupled together and cannot be directly separated. Therefore, to obtain accurate deformation data, it is necessary to acquire the temperature information of the submarine cable beforehand and remove it from the wavelength drift of the deformation sensing optical cable, thereby calculating a pure strain signal. This process is known as temperature compensation correction.

[0049] Existing technologies typically employ separate deformation-sensing optical cables and temperature-sensing optical cables. The deformation-sensing cable acquires a mixed signal containing both temperature and strain information, while the temperature-sensing cable acquires temperature information separately. The temperature-sensing cable is then used to compensate and correct the mixed signal from the deformation-sensing cable, thereby calculating the pure strain distribution. However, the internal space of submarine cables is limited, and simultaneously deploying both types of sensing optical cables complicates the structure, requires more fiber optic channels, and increases manufacturing costs.

[0050] Furthermore, the strain of the deformation sensing optical cable must be consistent with that of the submarine cable itself; that is, the strain state of the optical cable should be exactly the same as that of the submarine cable to ensure the accuracy of strain transmission and the reliability of deformation reconstruction. However, the diameter of the deformation sensing optical cable is usually only a few millimeters, which is much smaller than the cross-sectional size of the main cable core of the submarine cable, making it difficult to directly strand it into a cable as an independent unit with the main structure such as the power cable core.

[0051] To address this issue, existing technologies primarily increase the outer diameter of the deformation sensing optical cable to match the stranding profile of the main cable core, enabling the deformation sensing optical cable to be stranded with the main cable core. However, increasing the outer diameter of the deformation sensing optical cable leads to an increase in its bending stiffness, which can easily cause micro-bending loss or even breakage of the deformation sensing fiber under dynamic loads, making it impossible for the strain state of the deformation sensing optical cable to remain consistent with that of the submarine cable itself.

[0052] Another common approach is to create longitudinal grooves on the surface of the submarine cable's support frame to encapsulate the deformation-sensing optical cable within the grooves. However, this method requires grooving the support frame, which is complex and weakens the mechanical integrity of the support frame. Furthermore, the method of fixing the optical cable to the grooves makes it difficult to achieve a completely rigid coupling, resulting in inconsistent strain transmission.

[0053] Therefore, existing technologies cannot simultaneously detect deformation and temperature in the same sensing component, nor can they solve the problems of dimensional differences and rigid coupling between sensing optical cables and submarine cables.

[0054] In view of this, embodiments of this application provide a submarine cable and its sensing components.

[0055] The submarine cable and its sensing component provided in this application include a sensing optical cable and multiple coupling elements. The sensing optical cable is placed within a receiving slot of the submarine cable. Multiple first sensing units and multiple second sensing units are disposed on the sensing optical cable. The first sensing units are used to acquire temperature information of the submarine cable, and the second sensing units are used to acquire strain and temperature information of the submarine cable. The multiple first sensing units and multiple second sensing units are alternately spaced along the axial direction of the sensing optical cable. Integrating the first and second sensing units into the same sensing optical cable simplifies the internal structure of the submarine cable and reduces the occupation of optical fiber channels.

[0056] The coupling element is constructed to form a through-hole with openings at both ends, allowing it to be fitted over the outside of the sensing optical cable. A second sensing unit is positioned between two adjacent coupling elements. The coupling element can transmit the deformation of the submarine cable to the sensing optical cable.

[0057] The coupling element includes a body and at least one limiting part. The limiting part is located at the axial end of the body, and a through-channel passes through the body and the limiting part axially. An anchoring part is provided on the inner side of the body, and the inner structure of the anchoring part forms part of the through-channel. Each first sensing unit is located inside the anchoring part in one of the coupling elements, and the stiffness of the anchoring part is greater than that of the body. The anchoring part can be used to form a rigid constraint on the section of the sensing optical cable corresponding to the first sensing unit, so that the sensing optical cable in that section does not generate axial strain during the deformation of the submarine cable, thereby ensuring that the first sensing unit only responds to the temperature of the submarine cable, and its output signal can be used as a pure temperature reference to perform temperature compensation on the output signal of the second sensing unit, separating the pure strain information generated by the deformation of the submarine cable.

[0058] A limiting part is located at the end of the main body, with its outer peripheral edge protruding beyond the outer peripheral edge of the main body. When the submarine cable is in a free state, the limiting part remains in contact with the inner wall of the receiving groove. When the submarine cable bends, the receiving groove deforms along with the cable, and the limiting part forms abutment contact with the inner wall of the receiving groove. The coupling member can transmit the deformation of the submarine cable to the main body through the limiting part, causing the main body to bend synchronously with the submarine cable.

[0059] Therefore, the sensing component of this application can simultaneously achieve high-precision measurement of temperature self-compensation and submarine cable deformation through a single sensing optical cable, thereby simplifying the internal structure of the submarine cable and avoiding the problem of deterioration in bending performance caused by thickening of the sensing optical cable.

[0060] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0061] Figure 1 This is a schematic diagram of the structure of a submarine cable provided in an embodiment of this application. (Refer to...) Figure 1 This application provides a submarine cable 1, which includes a cable body 20. The cable body 20 includes a cable core 21, a support sleeve 22, and an outer sheath 23. The cable core 21 can be used to realize power transmission or signal communication. The cable core 21 may include one or more power transmission conductors and communication optical fiber units.

[0062] The support sleeve 22 is disposed on the outside of the cable core 21, and can be used to provide mechanical support and protection for the cable core 21, and maintain the roundness of the cross-section of the submarine cable 1. The outer sheath 23 covers the outer periphery of the support sleeve 22 and the cable core 21, and is used to isolate seawater, resist the attachment and gnawing of marine organisms, and prevent mechanical damage caused by external forces, so as to ensure the long-term safe operation of the submarine cable 1 in the marine environment. For example, the outer sheath 23 can be made of high-density polyethylene, polypropylene, or hydrolysis-resistant polyurethane material.

[0063] Continue to refer to Figure 1 The submarine cable 1 also includes a sensing component 10 (hereinafter referred to as sensing component 10) for the submarine cable. The support sleeve 22 is configured to form an axially extending receiving groove 22a, in which the sensing component 10 can be disposed. The receiving groove 22a can be used to receive the sensing component 10 and to position and fix the sensing component 10 so that the sensing component 10 can move synchronously with the submarine cable 1 and sense the deformation state of the submarine cable 1.

[0064] The sensing component 10 provided in this application can be used for monitoring the structural integrity of dynamic submarine cables. By deploying the sensing component 10 inside the dynamic submarine cable, the temperature distribution information and strain-temperature coupling information of the dynamic submarine cable can be acquired in real time. After compensation and correction, accurate strain data can be obtained, providing data support for the three-dimensional morphology reconstruction and health status assessment of the submarine cable.

[0065] Alternatively, the sensing component 10 can also be used for long-term structural monitoring of static submarine cables. Although static submarine cables do not bear frequent dynamic loads, factors such as changes in seabed temperature, ocean current erosion, and bending due to the weight of the suspended section can still cause structural deformation. The sensing component 10 of this application can simultaneously acquire temperature information and strain-temperature coupling information, enabling real-time monitoring and early warning of the long-term operating status of static submarine cables.

[0066] Of course, the sensing component 10 of this application can also be used for structural monitoring of other marine flexible pipelines or cables, such as marine umbilical cables, flexible risers, and dynamic oil pipelines. The above is merely an illustrative description of the application scenarios of the sensing component 10 in the embodiments of this application, and is not intended to limit the application scenarios of the sensing component 10 in the embodiments of this application.

[0067] Continue to refer to Figure 1 The sensing component 10 includes a sensing optical cable 100, which is placed in the receiving groove 22a of the submarine cable 1. The sensing optical cable 100 is provided with a plurality of first sensing units 200 and a plurality of second sensing units 300, which are arranged alternately at intervals along the axial direction of the sensing optical cable 100.

[0068] The first sensing unit 200 can be used to acquire temperature information of the environment where the submarine cable 1 is located, and the second sensing unit 300 can be used to acquire temperature information of the submarine cable 1 and strain information caused by dynamic load.

[0069] It should be noted that in fiber optic sensing technology, the output signal of the sensing unit is simultaneously affected by both temperature and strain; that is, changes in both temperature and strain will cause changes in the output signal of the sensing unit. This phenomenon is called cross-sensitivity. In order to separate strain information from the output signal of the sensing unit, temperature information needs to be obtained as a compensation reference.

[0070] Based on this, when the submarine cable 1 is bent or stretched, the sensing optical cable 100 in the section where the second sensing unit 300 is located can deform synchronously with the submarine cable body 20, so that the second sensing unit 300 can respond to temperature and strain simultaneously.

[0071] The first sensing unit 200 provided in this application is configured to respond only to ambient temperature and is not sensitive to deformation of the submarine cable 1. Therefore, the signal output by the first sensing unit 200 contains only temperature information and can be used as a pure temperature reference.

[0072] In this way, the sensing component 10 provided in this application can use the pure temperature signal obtained by the first sensing unit 200 to subtract the part caused by temperature change from the output signal of the second sensing unit 300, thereby separating the pure strain information generated only by the deformation of the submarine cable 1.

[0073] With this configuration, the sensing component 10 can achieve temperature self-compensation without the need for an additional independent sensing optical cable 100, thus eliminating the need for additional internal space in the submarine cable 1. This simplifies the overall structure of the submarine cable 1 and reduces manufacturing and maintenance costs. Simultaneously, it addresses the issue of cross-sensitivity between temperature and strain in fiber optic sensing, improving the accuracy and reliability of deformation monitoring in the submarine cable 1.

[0074] In this embodiment, the sensing optical cable 100 may include a central optical fiber 110, multiple peripheral optical fibers 120, and multiple support units 130. The multiple peripheral optical fibers 120 are circumferentially spaced around the central optical fiber 110. The multiple support units 130 are circumferentially spaced around the central optical fiber 110, and the multiple support units 130 and the multiple peripheral optical fibers 120 are alternately arranged. A first sensing unit 200 is disposed on the central optical fiber 110, and a second sensing unit 300 is disposed on the peripheral optical fibers 120.

[0075] In some possible embodiments, the support unit 130 and the peripheral optical fiber 120 may each be provided with three support units 130, and the three support units 130 and the three peripheral optical fibers 120 may be alternately arranged.

[0076] Thus, the central optical fiber 110 is located at the center of the cross-section of the sensing optical cable 100. When the sensing optical cable 100 bends along with the submarine cable body 20, the axial strain of the central optical fiber 110 is minimal, and it is minimally affected by the bending of the submarine cable body 20.

[0077] The peripheral optical fibers 120 are distributed in different radial directions on the cross section of the sensing optical cable 100. When the sensing optical cable 100 bends along with the submarine cable body 20, the peripheral optical fibers 120 in different directions are in the tensile zone or the compression zone, which can generate corresponding axial strain. The second sensing unit 300 set on the peripheral optical fibers 120 can sense this strain information.

[0078] The support unit 130 can be made of fiber-reinforced polymer matrix composite material. The support unit 130 and the peripheral optical fiber 120 are arranged alternately, which can fix the position of the peripheral optical fiber 120 on the cross section of the sensing optical cable 100, and ensure that the relative orientation between each peripheral optical fiber 120 remains stable during the manufacturing and long-term use of the sensing optical cable 100, thereby ensuring the orientation consistency of strain measurement.

[0079] Meanwhile, the support unit 130 has high modulus characteristics, which can provide sufficient compressive strength and structural stability for the sensing optical cable 100, preventing micro-bending loss or signal distortion of the sensing optical cable 100 due to external compression during the operation of the submarine cable 1.

[0080] This configuration allows the submarine cable 1 of this application to acquire strain information and temperature compensation information simultaneously through a single sensing optical cable 100 without the need for multiple independent sensing optical cables 100. This simplifies the structure of the submarine cable 1 and reduces manufacturing and deployment costs.

[0081] Reference Figure 1 The sensing component 10 also includes a plurality of coupling elements 400, each coupling element 400 being configured to form a through-channel 400c with openings at both ends, so that the coupling element 400 is fitted onto the outside of the sensing optical cable 100. The plurality of coupling elements 400 can be spaced apart along the axial direction of the sensing optical cable 100, and the second sensing unit 300 can be disposed between two adjacent coupling elements 400.

[0082] In this way, when the coupling member 400 bends or shifts along with the submarine cable body 20, it can transmit the deformation state of the submarine cable body 20 to the sensing optical cable 100, thereby causing the sensing optical cable 100 between two adjacent coupling members 400 to generate corresponding strain, and the second sensing unit 300 located on the section of the sensing optical cable 100 can sense the strain information.

[0083] Figure 2 This is a cross-sectional structural diagram of the sensing component provided in the embodiments of this application when the coupling element is assembled on the outside of the sensing optical cable. Figure 3 This is a schematic diagram of the coupling element in the sensing assembly provided in an embodiment of this application. (Refer to...) Figure 2 and Figure 3 The coupling member 400 may include a body portion 410 and at least one limiting portion 420, the limiting portion 420 being disposed at the axial end of the body portion 410. A through-passage 400c extends axially through the body portion 410 and the limiting portion 420.

[0084] The main body 410 forms a first channel, and the limiting part 420 forms a second channel. The main body and the limiting part are connected along the axial direction of the sensing optical cable 100. The first channel and the second channel are connected and form a through channel 400c.

[0085] The outer peripheral edge of the limiting part 420 protrudes beyond the outer peripheral edge of the main body part 410. When the submarine cable 1 bends, the limiting part 420 forms abutment contact with the inner wall of the receiving groove 22a, thereby transmitting the deformation of the submarine cable 1 to the main body part 410 through the limiting part 420, causing the main body part 410 to bend synchronously with the submarine cable 1. Through the contact between the limiting part 420 and the receiving groove 22a, rapid response and accurate transmission of deformation of the main body part 410 can be achieved, ensuring that the strain information sensed by the sensing optical cable 100 is highly consistent with the actual deformation state of the submarine cable 1, providing structural protection for the accurate monitoring of the dynamic submarine cable 1.

[0086] In some possible embodiments, the outer peripheral contour of the limiting part 420 can be adapted to the cross-sectional shape of the receiving groove 22a. In this way, when the submarine cable 1 bends and the limiting part 420 comes into contact with the inner wall of the receiving groove 22a, the contour of the limiting part 420 adapted to the receiving groove 22a can make the contact force evenly distributed on the outer peripheral edge of the limiting part 420, avoiding structural damage or deformation failure caused by local stress concentration.

[0087] In addition, the contour of the limiting part 420 that is adapted to the receiving groove 22a can also limit the rotational freedom of the limiting part 420 within the receiving groove 22a, so that the coupling member 400 can only be displaced and bent along the extension direction of the receiving groove 22a, and cannot be twisted around its own axis, thereby ensuring that the orientation of the sensing optical cable 100 inside the coupling member 400 remains stable and avoiding signal crosstalk or measurement errors caused by twisting.

[0088] In some possible implementations, the cross-sectional shape of the receiving groove 22a can be pentagonal, and the outer periphery of the limiting part 420 can also be pentagonal. Of course, the cross-sectional shape of the receiving groove 22a and the outer periphery of the limiting part 420 can also be rectangular, square, circular, or other shapes, and this application embodiment does not impose specific limitations on them.

[0089] A gap may be provided between the limiting part 420 and the inner wall of the receiving groove 22a. In this way, the coupling member 400 can be unrestrained when the submarine cable 1 is in a free state, and the sensing optical cable 100 can remain in a relaxed state, avoiding fiber fatigue or creep caused by long-term pre-tension.

[0090] In some possible embodiments, the coupling member 400 may include two limiting portions 420, with one limiting portion 420 respectively provided at each end of the main body 410. Thus, when the submarine cable 1 bends, the two limiting portions 420, respectively located at the axial ends of the main body 410, can ensure that the coupling member 400 is subjected to balanced force, uniformly transmitting the bending deformation of the submarine cable 1 to the main body 410, ensuring that the strain information sensed by the sensing optical cable 100 is consistent with the actual deformation state of the submarine cable 1. Simultaneously, the two limiting portions 420 can clamp and fix the coupling member 400 within the receiving groove 22a, preventing the coupling member 400 from deflecting or overturning due to unilateral force.

[0091] An arc transition section may be provided at the connection between the main body 410 and the limiting part 420 to disperse stress concentration and improve the connection strength between the main body 410 and the limiting part 420.

[0092] An anchoring portion 430 is provided on the inner side of the main body 410, and the inner structure of the anchoring portion 430 forms a portion of the passage channel 400c. The stiffness of the anchoring portion 430 is greater than that of the main body 410. Each first sensing unit 200 is located inside the anchoring portion 430 within one of the coupling members 400. The anchoring portion 430 can be used to rigidly fix the section of the sensing optical cable 100 corresponding to the first sensing unit 200. When the submarine cable 1 deforms, the anchoring portion 430 can constrain the section of the sensing optical cable 100 inside it, so that the section of the sensing optical cable 100 does not generate axial strain during the deformation of the submarine cable 1. Therefore, the first sensing unit 200 located inside the anchoring portion 430 only responds to the temperature of the submarine cable 1, and its output signal does not contain strain information, and can be used as a pure temperature reference.

[0093] The anchoring part 430 can be made of a high-rigidity material, making its elastic modulus higher than that of the body part 410. For example, the anchoring part 430 can be made of a metal material with high rigidity and good machining accuracy, such as stainless steel, titanium alloy or aluminum alloy.

[0094] An anchoring medium layer (not shown in the figure) can be provided between the anchoring part 430 and the sensing optical cable 100. The anchoring medium layer can fix the sensing optical cable 100 to the anchoring part 430, so that the section of the sensing optical cable 100 corresponding to the first sensing unit 200 is rigidly constrained within the anchoring part 430, and no axial strain is generated during the deformation of the submarine cable 1. The anchoring medium layer can eliminate the gap between the sensing optical cable 100 and the anchoring part 430, and avoid fretting wear or signal drift of the sensing optical cable 100 caused by the existence of gaps.

[0095] The anchoring medium layer must have sufficient bonding strength and post-curing stiffness to ensure that the sensing optical cable 100 is fully constrained within the anchoring portion 430 and that no axial strain occurs during the deformation of the submarine cable 1. Simultaneously, the anchoring medium layer should possess a certain degree of toughness or have a coefficient of thermal expansion matching that of the outer sheath material of the sensing optical cable 100 to absorb thermal stress generated between the anchoring portion 430 and the sensing optical cable 100 due to temperature changes.

[0096] For example, the anchoring medium layer can be made of epoxy resin adhesive with high bonding strength and high rigidity after curing. Alternatively, the anchoring medium layer can also be made of polyurethane adhesive with good toughness; this application embodiment does not impose specific limitations on this.

[0097] The main body 410 includes a bearing sleeve 411, which is connected to the limiting part 420, and an anchoring part 430 is disposed inside the bearing sleeve 411. The bearing sleeve 411 can be made of a high-rigidity material. For example, the bearing sleeve can be made of fiber-reinforced polyetheretherketone composite material or glass fiber-reinforced epoxy resin. This application embodiment does not impose specific limitations on this.

[0098] The elastic modulus of the bearing sleeve 411 can be no less than 8 GPa. For example, the elastic modulus of the bearing sleeve 411 can be 9.2 GPa. The bearing sleeve 411 can be used to provide a stable mounting base for the anchor part 430, so that the anchor part 430 can be reliably fixed to the inside of the bearing sleeve 411, thereby ensuring the restraining effect of the anchor part 430 on the sensing optical cable 100.

[0099] When the submarine cable 1 bends or is subjected to external pressure, the bearing sleeve 411 can withstand the main mechanical load, preventing the anchoring part 430 from deforming or being damaged due to excessive local stress, and ensuring that the coupling part 400 maintains its overall shape under long-term dynamic load.

[0100] In some possible embodiments, the outer wall of the bearing sleeve 411 may be configured to form a spiral groove 4111, which may extend spirally along the axial direction of the bearing sleeve 411. The spiral groove 4111 can be used to reduce the bending stiffness of the bearing sleeve 411, so that the bearing sleeve 411 can undergo consistent bending deformation with the submarine cable 1 while maintaining radial load-bearing capacity and circumferential stability.

[0101] When the submarine cable 1 bends, the spiral groove 4111 can make the bearing sleeve 411 have sufficient bending flexibility, so that the bending shape of the bearing sleeve 411 matches the bending shape of the submarine cable 1, ensuring that the deformation of the submarine cable 1 can be transmitted to the inner sensing optical cable 100 through the bearing sleeve 411.

[0102] Continue to refer to Figure 2The body portion 410 may further include a flexible interface layer 412, which is located at both ends of the anchor portion 430 along the axial direction and between the sensing optical cable 100 and the carrier sleeve 411. The flexible interface layer 412 may be made of a low-modulus flexible material, and the elastic modulus of the flexible interface layer 412 is lower than that of the carrier sleeve 411 and the anchor portion 430. For example, the flexible interface layer 412 may be made of fluorosilicone gel.

[0103] When the coupling element 400 bends with the submarine cable 1, the sensing optical cable 100 and the carrier sleeve 411 may have local curvature inconsistencies due to the difference in bending radius. The flexible interface layer 412 can absorb this curvature difference through its own low modulus shear deformation, so that the sensing optical cable 100 can smoothly transition at the entrance and exit of the coupling element 400, avoiding micro-bending loss caused by local bending or curvature change of the sensing optical cable 100.

[0104] Meanwhile, the flexible interface layer 412 can provide flexible support for the sensing optical cable 100, preventing wear or stress concentration caused by rigid contact between the sensing optical cable 100 and the bearing sleeve 411.

[0105] The main body 410 also includes a stress buffer layer 413, which may be located inside the bearing sleeve 411. The stress buffer layer 413 may include a first portion 4131 and a second portion 4132. The first portion 4131 is located between the bearing sleeve 411 and the anchoring portion 430, and is used to absorb stress transmission between the bearing sleeve 411 and the anchoring portion 430, preventing the anchoring portion 430 from shifting due to deformation of the bearing sleeve 411.

[0106] The second part 4132 is located between the bearing sleeve 411 and the flexible interface layer 412, and is disposed at both ends of the anchoring part 430. It can absorb the shear energy generated by the relative displacement between the bearing sleeve 411 and the flexible interface layer 412. When the coupling member 400 bends with the submarine cable 1, shear stress is generated between the bearing sleeve 411 and the flexible interface layer 412 due to the difference in material stiffness and deformation. The stress buffer layer 413 absorbs this energy through its own shear deformation, preventing interface peeling or delamination failure between the bearing sleeve 411 and the flexible interface layer 412.

[0107] The stress buffer layer 413 can be made of anisotropic composite material. For example, the stress buffer layer 413 can be made of chopped glass fiber reinforced silicone rubber. The radial modulus of elasticity of the stress buffer layer 413 can be greater than its axial modulus of elasticity. For example, the radial modulus of the stress buffer layer 413 can be from 300 MPa to 500 MPa, and the axial modulus of the stress buffer layer 413 can be from 30 MPa to 50 MPa. For example, the radial modulus of the stress buffer layer 413 can be 420 MPa, and the axial modulus of the stress buffer layer 413 can be 38 MPa.

[0108] In this embodiment, the outer diameter of the limiting part 420 can be 19 mm, the thickness of the limiting part 420 can be 2 mm, and a 1 mm gap can be provided between the limiting part 420 and the inner wall of the receiving groove 22a. The outer diameter of the body part 410 can be 15 mm, the inner diameter of the body part 410 can be 5 mm, and the wall thickness of the body part 410 can be 5 mm. The thickness of the bearing sleeve 411 can be 3 mm, the thickness of the second part 4132 of the stress buffer layer 413 can be 1.5 mm, and the thickness of the flexible interface layer 412 can be 0.5 mm. The pitch of the spiral groove 4111 can be 5 mm, and the groove depth of the spiral groove 4111 can be 2 mm. It is understood that the above-mentioned dimensional parameters are only one implementation method provided by this embodiment. In practical applications, they can be adaptively adjusted according to the specifications, monitoring accuracy, and mechanical performance requirements of the submarine cable 1. This embodiment does not specifically limit this.

[0109] Figure 4 This is a schematic diagram of the structure of the first coupling part or the second coupling part in the sensing component provided in the embodiments of this application. (Refer to...) Figure 4 In this embodiment of the application, the coupling member 400 may include a first coupling portion 400a and a second coupling portion 400b, wherein the first coupling portion 400a has a first body and the second coupling portion 400b has a second body. The first body and the second body enclose to form a through channel 400c. At least one of the first coupling portion 400a and the second coupling portion 400b has a limiting portion 420 at its end.

[0110] This configuration allows the sensing optical cable 100 to be easily assembled inside the coupling member 400. During assembly, the sensing optical cable 100 can be placed inside the first body or the second body first, and then the first body and the second body can be connected, so that the sensing optical cable 100 is wrapped inside the coupling member 400, without having to be inserted from one end of the through-channel 400c, thereby simplifying the assembly process and improving production efficiency.

[0111] A positioning pin (not shown in the figure) may be provided on the first coupling part 400a, and a positioning hole (not shown in the figure) may be constructed on the corresponding part of the second coupling part 400b. The first coupling part 400a and the second coupling part 400b can be precisely aligned by the positioning pin and the positioning hole, so as to prevent the optical cable position deviation or the failure of the fit between the limiting part 420 and the receiving groove 22a due to assembly misalignment.

[0112] In some possible implementations, the first coupling portion 400a and the second coupling portion 400b can be fixedly connected by adhesive bonding. Specifically, an adhesive can be applied to the mating surfaces of the first coupling portion 400a and the second coupling portion 400b. For example, a two-component epoxy structural adhesive can be applied to the mating surfaces of the first coupling portion 400a and the second coupling portion 400b. After aligning the positioning pin on the first coupling portion 400a with the positioning hole on the second coupling portion 400b, the first coupling portion 400a and the second coupling portion 400b are brought into close contact, and a predetermined pressure is applied to the first coupling portion 400a and the second coupling portion 400b and held for 30 seconds to allow the adhesive to cure rapidly, thereby achieving a reliable connection between the first coupling portion 400a and the second coupling portion 400b.

[0113] Of course, the first coupling part 400a and the second coupling part 400b can also be connected by bolts, snaps or other means, and this application embodiment does not make specific limitations on this.

[0114] Based on the position of the first sensing unit 200 on the sensing optical cable 100, a plurality of coupling members 400 are sequentially sleeved on the outside of the sensing optical cable 100, so that each first sensing unit 200 is located inside the anchoring part 430 of the corresponding coupling member 400, and each second sensing unit 300 is located between two adjacent coupling members 400, thereby forming a sensing assembly 10 equipped with coupling members 400.

[0115] The sensing component 10 is arranged in the receiving groove 22a. Alternatively, the sensing component 10 can be directly inserted into the receiving groove 22a of the formed submarine cable 1. Or, the sensing component 10 can be inserted into the receiving groove 22a first, and then wrapped according to the cabling process of the submarine cable 1 to complete the mechanical coupling between the sensing component 10 and the submarine cable body 20. This embodiment does not impose specific limitations on this approach.

[0116] It should be noted that the terms "an embodiment," "an embodiment," "an exemplary embodiment," "some embodiments," etc., mentioned in the specification may include specific features, structures, or characteristics, but not every embodiment necessarily includes that specific feature, structure, or characteristic. Furthermore, such phrases do not necessarily refer to the same embodiment. Additionally, when describing a specific feature, structure, or characteristic in conjunction with embodiments, implementing such a feature, structure, or characteristic in conjunction with other embodiments, whether explicitly described or not, is within the knowledge scope of those skilled in the art.

[0117] Generally speaking, terms should be understood at least in part by their use in context. For example, at least in part by context, the term "one or more" as used in the text can be used to describe any feature, structure, or characteristic of the singular meaning, or a combination of features, structures, or characteristics of the plural meaning. Similarly, at least in part by context, terms such as "one" can be understood to convey either singular or plural usage.

[0118] It should be readily understood that the terms “on,” “above,” and “on top of” in this application should be interpreted in the broadest possible sense, such that “on” means not only “directly on something” but also “on something” with an intermediate feature or layer therebetween, and that “above” or “on top of” means not only “on something” but also “on something” without an intermediate feature or layer therebetween (i.e., directly on something).

[0119] Furthermore, for ease of explanation, spatially relative terms such as "below," "below," "under," "above," and "above" may be used to describe the relationship of one element or feature relative to other elements or features as shown in the figures. Spatially relative terms are intended to encompass different orientations of the device in use or operation other than those shown in the figures. The device may have other orientations (rotated 90° or in other orientations), and the spatially relative descriptive terms used herein may be interpreted accordingly.

[0120] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A sensing component for submarine cables, characterized in that, include: A sensing optical cable is used to be placed in the receiving groove of the submarine cable. The sensing optical cable is provided with multiple first sensing units and multiple second sensing units. The first sensing units are used to acquire the temperature information of the submarine cable, and the second sensing units are used to acquire the strain and temperature information of the submarine cable. Multiple first sensing units and multiple second sensing units are alternately spaced along the axial direction of the sensing optical cable; Multiple coupling elements are provided, each coupling element being configured to form a through-channel with openings at both ends, so that the coupling element is fitted onto the outside of the sensing optical cable; the second sensing unit is disposed between two adjacent coupling elements. The coupling member includes a body portion and at least one limiting portion; the limiting portion is disposed at the axial end of the body portion, and the through-channel passes through the body portion and the limiting portion axially; An anchoring portion is provided on the inner side of the main body, and the stiffness of the anchoring portion is greater than that of the main body; the inner side of the anchoring portion forms the portion of the through-channel; each of the first sensing units is located on the inner side of the anchoring portion within one of the coupling members. The outer peripheral edge of the limiting part protrudes beyond the outer peripheral edge of the body part; the limiting part is configured to abut against the inner wall of the receiving groove when the submarine cable bends, so that the body part deforms with the submarine cable.

2. The sensing component according to claim 1, characterized in that, An anchoring medium layer is provided between the anchoring part and the sensing optical cable.

3. The sensing component according to claim 1, characterized in that, The main body includes a bearing sleeve, which is connected to the limiting part, and the anchoring part is disposed inside the bearing sleeve.

4. The sensing component according to claim 3, characterized in that, The outer wall of the bearing sleeve is constructed to form a spiral groove.

5. The sensing component according to claim 3, characterized in that, The body portion further includes a flexible interface layer located at both ends of the anchor portion along the axial direction and between the sensing optical cable and the bearing sleeve, for providing support for the sensing optical cable when the coupling member bends.

6. The sensing component according to claim 5, characterized in that, The main body also includes a stress buffer layer located inside the bearing sleeve; the radial elastic modulus of the stress buffer layer is greater than its axial elastic modulus; the stress buffer layer is used to absorb the shear energy generated by the relative displacement between the bearing sleeve and the flexible interface layer. The stress buffer layer includes a first part and a second part. The first part is located between the bearing sleeve and the anchoring part; the second part is located between the bearing sleeve and the flexible interface layer, and at both ends of the anchoring part.

7. The sensing component according to any one of claims 1-6, characterized in that, The outer periphery of the limiting part is adapted to the cross-sectional shape of the receiving groove.

8. The sensing component according to any one of claims 1-6, characterized in that, The coupling element includes a first coupling portion and a second coupling portion. The first coupling portion includes a first body, and the second coupling portion includes a second body. The first body and the second body enclose and form the through-channel. The limiting portion is provided at the end of at least one of the first coupling portion and the second coupling portion.

9. The sensing component according to any one of claims 1-6, characterized in that, The sensing optical cable includes: Central optical fiber; Multiple peripheral optical fibers are distributed circumferentially around the central optical fiber; Multiple support units are distributed circumferentially around the central optical fiber and are alternately arranged with the peripheral optical fibers; The first sensing unit is disposed on the central optical fiber, and the second sensing unit is disposed on the peripheral optical fiber.

10. A submarine cable, characterized in that, include: The sensing component as claimed in any one of claims 1-9; The submarine cable body includes a cable core, a support sleeve, and an outer sheath; the support sleeve is disposed on the outside of the cable core, and the support sleeve is configured to form an axially extending receiving groove; the sensing component is disposed in the receiving groove; the outer sheath covers the outside of the support sleeve and the cable core.

Images