Submarine cable maintenance method

Abstract

The invention discloses a submarine cable maintenance method. The method specifically comprises the operation steps of S1, DP positioning and cement row protection cleaning, S2, fault point cutting-off treatment, S3, anchoring device dismantling, S4, protection point cutting-off and protection device recycling, S5, new submarine cable traction and anchoring device installation, S6, water depth measurement and submarine cable demand quantity measurement and calculation, S7, joint manufacturing, S8, submarine cable lowering treatment, S9, cement row and protection object covering, S10, handover testing and the like. The self-propelled workboat with the DP positioning function is adopted, a diver and a connector manufacturing worker are matched for maintenance, the traffic boat is adopted for assistance, only the diver and a technician in the connector manufacturing procedure are needed to be matched in the maintenance process, the operation process is short, and the method has the advantages of being safe, efficient, high in adaptability and low in uniform maintenance price; the maintenance efficiency is improved on the basis of reducing the personnel configuration number and configuration level, the submarine cable fault time can be effectively shortened, and the power transmission stability is improved.

Description

Technical Field

[0001] The invention relates to a submarine cable maintenance method and belongs to the technical field of submarine cable maintenance. Background Art

[0002] In offshore wind power projects, submarine cables are the blood vessels for offshore wind farms to transmit electricity to the outside world. The stability and reliability of their transmission are crucial to the stability of wind turbine power generation. With the rapid development of offshore wind power projects, the application scale of submarine cables is expanding. With the increase in the amount of submarine cables laid, their maintenance work is also increasing. The maintenance response speed has become an important factor affecting the stability of submarine cables. The existing submarine cable maintenance methods generally have insufficient maintenance efficiency, low adaptability, and are greatly affected by the construction environment. Summary of the invention

[0003] In order to solve the above problems in the background technology, the present invention provides a submarine cable maintenance method.

[0004] The technical solution to achieve the purpose of the present invention is: a submarine cable maintenance method, comprising the following steps:

[0005] S1: Drive the DP positioning ship to the laying location, clean the submarine cable and cover it with cement strips for protection;

[0006] S2: Cut the cable at the fault point, bundle the submarine cable and salvage the submarine cable end to the cable laying vessel;

[0007] S3: Remove the submarine cable anchoring device and pull the submarine cable to the wind turbine;

[0008] S4: Cut off the submarine cable protection point and recycle the protection device of the submarine cable protection point inside and outside the wind turbine. During the recycling process, reserve the pulling wire on the wind turbine;

[0009] S5: Connect the pulling wire to the new submarine cable protection device and the submarine cable, pull the submarine cable to the set position of the wind turbine, and then install the anchoring device;

[0010] S6: Measure the water depth, the length required for making the submarine cable joint, and cut the submarine cable;

[0011] S7: making joints;

[0012] S8: lowering the submarine cable;

[0013] S9: Perform cement joint restoration and cover protection treatment on the submarine cable;

[0014] S10: Perform handover test.

[0015] The submarine cable repair method adopted in the present application adopts a self-propelled work boat with DP positioning function, and the repair is carried out by divers and joint makers. A transport boat can be used as an auxiliary in the repair process. The submarine cable is connected by pulling and positioning in the repair process. The repair process only requires the cooperation of divers and technicians in the joint making process. Compared with the method of repairing the submarine cable after salvaging the entire cable ashore, the operation process is short and it is safe, efficient, highly adaptable and has the characteristics of low amortized repair price. It improves the maintenance efficiency on the basis of reducing the number and level of personnel configuration, which can effectively shorten the failure time of the submarine cable and improve the stability of power transmission.

[0016] The method for cleaning the cement bundling protection covering the submarine cable in step S1 is: a diver dives to the laying location, removes the silt covering the submarine cable in the area until the damaged location of the cable is exposed, and then further cleans the damaged location until the debris covering the cable at the damaged location is removed.

[0017] This step is the basis for subsequent operations. It is conducive to effectively locating the fault location and can effectively avoid secondary damage caused by unclear specific circumstances during operation. Compared with large-scale excavation or the use of powerful equipment, it has less impact on the marine environment.

[0018] The specific method for cutting off the fault point in step S4 is: the diver cuts the submarine cable at the fault point, then ties the submarine cable end to the ship crane, and then uses the crane to salvage the submarine cable to the cable laying ship; after the cutting process, the cable at the wind turbine end is waterproofed.

[0019] During the above operation, the diver accurately cuts the fault point and the crane safely transfers the cut submarine cable to the cable laying ship, ensuring the targetedness and effectiveness of subsequent work and avoiding blind operation and the risk of damage during the submarine cable transfer. Compared with existing solutions, it has stronger stability and lower subsequent maintenance costs.

[0020] During the process of cutting the submarine cable protection point, the diver dives to the corresponding position of the submarine cable protection device to complete the cutting, and then the personnel inside the wind turbine and the diver respectively connect the cut protection joint to the crane, and use the crane to pull the split parts to the designated position for transfer; after the diver connects the cut protection joint to the crane, he fixes the pulling wire extending from the wind turbine to the position where the submarine cable extends from the wind turbine, and performs preliminary fixation to prevent it from falling off in preparation for the next traction setting.

[0021] During the above-mentioned operation, the divers and the personnel inside the wind turbine worked together to reduce the risk of single-person operation. At the same time, the use of the crane reduced the safety hazards in the process of moving heavy objects. The initial fixing method used steel wire for pulling, which can effectively prevent falling off and further improve the stability of the operation. The collaborative work of the divers and the operators inside the wind turbine effectively simplified the process, improved the work efficiency, and made the overall operation process transfer smoother, which can effectively shorten the construction time and reduce the waste of working time caused by waiting or repeated operations.

[0022] In step S5, the method for connecting the new submarine cable protection device and the submarine cable by pulling the steel wire is as follows: when the cable-laying vessel travels close to the wind turbine, a temporary fixing point is set under the cable-laying vessel, and after the underwater pulling device with a waterproof function is placed at the temporary fixing point, the pulling steel wire of the underwater pulling device is connected to the new submarine cable, and the underwater pulling device pulls the new cable and connects the new cable to the wind turbine.

[0023] In this operation procedure, an underwater pulling device is used to set the precise laying path of the new submarine cable, which effectively avoids the position deviation that may occur in the traditional laying method. The waterproof function of the underwater pulling device ensures the normal operation of the equipment in a complex marine environment and improves the overall reliability of the maintenance process. Its precise pulling path design can effectively improve the maintainability of the laying path and facilitate the subsequent work.

[0024] The method for measuring the water depth and confirming the required length of the submarine cable joint in step S6 is: using sonar or depth meter to obtain water depth data, calculating the required submarine cable length according to the actual water depth of the submarine cable laying and the actual cable laying path, and setting the reserved amount to 5-10%.

[0025] During the above operation, sonar or depth meter is used for data collection, and the overall accuracy of data acquisition is relatively high, which can effectively reduce errors caused by inaccurate estimates, thereby effectively improving the overall reliability of the project. The set error of 5-10% not only takes into account the unstable factors in the construction process, but also avoids the waste caused by excessive reservation of resources. In the marine environment, the reserved length can also be used as a mechanical buffer area, ensuring the electrical performance and mechanical strength of the submarine cable in different environments, which is conducive to reducing failures and improving the stability of the system maintenance in the long-term maintenance of the cable.

[0026] The method for making the joint in step S7 is: introducing the two ends of the submarine cables to be connected into a special joint making platform, stripping, cleaning, insulation treatment, material filling, sealing and mechanical strength measurement are carried out in a dry and clean environment, and then testing its electrical performance.

[0027] The above operation process is carried out in a dry and clean environment, which can effectively prevent moisture and impurities from entering the cable, ensure the quality and long-term stability of the joint, and avoid corrosion and electrical failures caused by external pollution; its good joint production environment can improve the safety of the operation process and reduce the risk of staff contacting high-voltage cables due to mistakes; the joint production process and the electrical performance testing process are well connected, which effectively simplifies the operation process, reduces the conversion time between different processes, and is conducive to improving overall efficiency.

[0028] The specific method for performing cement interlocking restoration and covering protection treatment in step S9 is: confirming the fixed position of the submarine cable, cleaning the silt and debris at the fixed position, fixing the cement interlocking at the corresponding position, and then fixing the submarine cable tightly against the cement interlocking, and finally setting a protective layer on the surface of the submarine cable; the protective layer is concrete or other covering materials, and the protective layer is evenly set on the surface of the submarine cable.

[0029] During the above operation, the installation position of the submarine cable can be effectively confirmed by confirming and cleaning the fixed position, avoiding subsequent stability caused by position deviation; the fitting and fixation between the cement row and the submarine cable can provide effective support for the submarine cable, reducing the risk of the submarine cable moving in the ocean current; the concrete covering its surface provides an effective physical barrier for the cable, which can effectively remove the impact of environmental factors on the submarine cable and improve the overall life and maintainability.

[0030] The method for the handover test in step S10 is: after the installation is completed and the protection measures are restored, preliminary functional testing, abnormal problem correction, system-level testing and test data handover are carried out in sequence.

[0031] The preliminary functional test includes at least an insulation resistance test and a DC withstand voltage test, the system-level test includes at least an AC withstand voltage test, an impact test and a signal transmission test, and the test data includes at least a test date, test equipment, test data and conclusion.

[0032] During the above operation, a phased testing method is used to comprehensively verify the electrical performance and mechanical strength of the submarine cable system. When potential problems or abnormalities are found, they can be effectively corrected, avoiding these problems from causing more serious consequences during operation, which is beneficial to improving the overall safety and stability of the system. Complete and detailed data records are needed to simplify the maintenance process.

[0033] By adopting the above technical solution, the present invention has the following beneficial effects:

[0034] (1) The submarine cable repair method adopted in the application uses a self-propelled work boat with DP positioning function, and the repair is carried out by divers and joint makers. A transport boat can be used as an auxiliary in the repair process. The repair process adopts the pulling positioning method to connect the submarine cable. The repair process only requires the cooperation of divers and technicians in the joint making process. Compared with the method of repairing the submarine cable after salvaging the entire cable ashore, the operation process is short and it is safe, efficient, highly adaptable and has the characteristics of low average maintenance price. It improves the maintenance efficiency on the basis of reducing the number and level of personnel configuration, which can effectively shorten the failure time of the submarine cable and improve the stability of power transmission.

[0035] (2) This application uses a fixed-point diving method to accurately locate the fault location, effectively avoiding secondary damage caused by unclear specific circumstances during operation. Compared with large-scale excavation or the use of powerful equipment, it has less impact on the marine environment.

[0036] (3) The method of abnormal fault point in this application is that the diver accurately cuts the fault point and then the cut submarine cable is safely transferred to the cable laying ship by a crane, so as to ensure the pertinence and effectiveness of subsequent work and avoid blind operation and the risk of damage during the transfer of the submarine cable. Compared with the existing solution, it has stronger stability and lower subsequent maintenance costs.

[0037] (4) In the process of removing the broken cable, the divers and the personnel inside the wind turbine work together, which reduces the risk of single-person operation. At the same time, the use of the crane reduces the safety hazards in the process of moving heavy objects. The initial fixing method uses steel wire for pulling, which can effectively prevent it from falling off and further improve the stability of the operation. The collaborative work of the divers and the operators inside the wind turbine effectively simplifies the process and improves the work efficiency, making the overall operation process transfer smoother, effectively shortening the construction time and reducing the waste of time caused by waiting or repeated operations.

[0038] (5) The present application uses an underwater pulling device to set the precise laying path of the new submarine cable, effectively avoiding the position deviation that may occur in the traditional laying method. The waterproof function of the underwater pulling device ensures the normal operation of the equipment in a complex marine environment and improves the overall reliability of the maintenance process. Its precise pulling path design can effectively improve the maintainability of the laying path and facilitate the subsequent work.

[0039] (6) The present application uses sonar or depth meter for data collection, and the overall accuracy of data acquisition is relatively high, which can effectively reduce errors caused by inaccurate estimates, thereby effectively improving the overall reliability of the project. The set error of 5 to 10% not only takes into account the unstable factors in the construction process, but also avoids the waste caused by excessive reservation of resources. In the marine environment, the reserved length can also be used as a mechanical buffer area, ensuring the electrical performance and mechanical strength of the submarine cable in different environments, which is conducive to reducing failures and improving the stability of the system maintenance in the long-term maintenance of the cable.

[0040] (7) The connector manufacturing process of the present application is carried out in a dry and clean environment, which can effectively prevent moisture and impurities from entering the cable, ensure the quality and long-term stability of the connector, and avoid corrosion and electrical failures caused by external pollution; its good connector manufacturing environment can improve the safety of the operation process and reduce the risk of workers accidentally contacting high-voltage cables; the connector manufacturing process and the electrical performance testing process are well connected, which effectively simplifies the operation process, reduces the conversion time between different processes, and is conducive to improving overall efficiency.

[0041] (8) The present application confirms and cleans the fixed position by diving, and utilizes the bonding fixation between the cement row and the submarine cable to provide effective support for the submarine cable, thereby reducing the risk of the submarine cable moving in the ocean current; the concrete covering its surface provides an effective physical barrier for the cable, which can effectively remove the impact of environmental factors on the submarine cable and improve the overall life and maintainability.

[0042] (9) This application adopts a phased testing method to comprehensively verify the electrical performance and mechanical strength of the submarine cable system. When potential problems or abnormalities are found, they can be effectively corrected, avoiding these problems from causing more serious consequences during operation, which is beneficial to improving the overall safety and stability of the system. Complete and detailed data records are needed to simplify the maintenance process. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to make the content of the present invention more clearly understood, the present invention is further described in detail below according to specific embodiments and in conjunction with the accompanying drawings, wherein

[0044] Figure 1 It is a schematic diagram of the process of the present invention. DETAILED DESCRIPTION

[0045] In order to better understand the above technical solution, the above technical solution will be described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0046] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0047] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0048] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0049] In the description of the embodiments of the present invention, it should be understood that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, or are the orientations or positional relationships in which the inventive product is conventionally placed when used, or are the orientations or positional relationships conventionally understood by those skilled in the art. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0050] In the description of the embodiments of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "installed", "connected" and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected, or indirectly connected through an intermediate medium, or it can be the internal connection of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances. The present invention is further described below in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and cannot be used to limit the scope of protection of the present invention.

[0051] (Example 1)

[0052] Figure 1 This is an operational flow chart of this application.

[0053] The specific operation process includes

[0054] S1: Drive the DP positioning ship to the laying location, clean the submarine cable and cover it with cement strips for protection;

[0055] S2: Cut the cable at the fault point, bundle the submarine cable and salvage the submarine cable end to the cable laying vessel;

[0056] S3: Remove the submarine cable anchoring device and pull the submarine cable to the wind turbine;

[0057] S4: Cut off the submarine cable protection point and recycle the protection device of the submarine cable protection point inside and outside the wind turbine. During the recycling process, reserve the pulling wire on the wind turbine;

[0058] S5: Connect the pulling wire to the new submarine cable protection device and the submarine cable, pull the submarine cable to the set position of the wind turbine, and then install the anchoring device;

[0059] S6: Measure the water depth, the length required for making the submarine cable joint, and cut the submarine cable;

[0060] S7: making joints;

[0061] S8: lowering the submarine cable;

[0062] S9: Perform cement joint restoration and cover protection treatment on the submarine cable;

[0063] S10: Perform handover test.

[0064] The cement gang protection is usually located near the vertical body of the wind turbine. After the diver dives to the bottom of the wind turbine, he uses manual or portable machinery to clean the silt and other impurities on the surface of the gang protection, and then uses a mechanical gang protection to remove the cement blocks on the surface to expose the optical cable.

[0065] After the optical cable is effectively exposed, divers cut the cable along the side wall of the wind turbine and then bundle its ports. The cable-laying ship operator lowers the traction device for salvaging the submarine cable to the diving point, and the diver fixes the bundled submarine cable on the salvage traction device. Then the cable-laying ship staff starts the crane, and the cut faulty cable is lifted to the cable-laying ship.

[0066] After the diver completes cutting the faulty cable, he connects the pulling wire to the wind turbine end.

[0067] The detailed process is as follows:

[0068] The method for cleaning the cement bundling protection covering the submarine cable in step S1 is: a diver dives to the laying location, removes the silt covering the submarine cable in the area until the damaged location of the cable is exposed, and then further cleans the damaged location until the debris covering the cable at the damaged location is removed.

[0069] The specific method for cutting off the fault point in step S4 is: the diver cuts the submarine cable at the fault point, then ties the submarine cable end to the ship crane, and then uses the crane to salvage the submarine cable to the cable laying ship; after the cutting process, the cable at the wind turbine end is waterproofed.

[0070] During the process of cutting the submarine cable protection point, the diver dives to the corresponding position of the submarine cable protection device to complete the cutting, and then the personnel inside the wind turbine and the diver respectively connect the cut protection joint to the crane, and use the crane to pull the split parts to the designated position for transfer; after the diver connects the cut protection joint to the crane, he fixes the pulling wire extending from the wind turbine to the position where the submarine cable extends from the wind turbine, and performs preliminary fixation to prevent it from falling off in preparation for the next traction setting.

[0071] After the faulty cable is pulled out, start laying the new cable.

[0072] First, place the underwater pulling device at the set position. During the placement process, try to arrange it along the original laying path, and pay attention to maintaining its waterproof performance during the placement process.

[0073] In step S5, the method for connecting the new submarine cable protection device and the submarine cable by pulling the steel wire is as follows: when the cable-laying vessel travels close to the wind turbine, a temporary fixing point is set under the cable-laying vessel, and after the underwater pulling device with a waterproof function is placed at the temporary fixing point, the pulling steel wire of the underwater pulling device is connected to the new submarine cable, and the underwater pulling device pulls the new cable and connects the new cable to the wind turbine.

[0074] During the pulling process, the pulling wire at the wind turbine end is first passed through the cavity of the underwater pulling device to expose it, and then the new submarine cable is lowered by a crane. When the new submarine cable is lowered to the corresponding position of the underwater pulling device, the pulling wire of the wind turbine and the new steel wire are connected. Then the operator at the wind turbine end pulls the new cable through the cavity of the underwater pulling device. After it is completely passed through, the new submarine cable section is cut after leaving enough stress margin, and then it is connected to the original cable.

[0075] The specific margin test process needs to be calculated based on the water depth and ocean current conditions, and the specific data needs to be determined based on the test results.

[0076] The method for measuring the water depth and confirming the required length of the submarine cable joint is: use sonar or depth meter to obtain water depth data, calculate the required submarine cable length according to the actual water depth of the submarine cable laying and the actual cable laying path, set the reserve amount to 5-10%, and use a 5% margin setting when the ocean current disturbance around the wind turbine is small. When the ocean current disturbance around the wind turbine is large, increase the reserve amount. The test results during the actual construction process show that after the reserve amount exceeds 10%, the stress relief effect gradually decreases and the material cost is still within an acceptable range. Therefore, the control limit range of the remainder is 5% to 10%.

[0077] The method for making the joint in step S7 is: introducing the two ends of the submarine cables to be connected into a special joint making platform, stripping, cleaning, insulation treatment, material filling, sealing and mechanical strength measurement are carried out in a dry and clean environment, and then the electrical performance is tested. The operation and testing process is carried out in an operating chamber with a high-precision filtering device with negative pressure balance as much as possible to prevent impurities in the air from contaminating the contact surface and causing changes in electrical performance. During the operation, the layers that can be made in an integrated manner are made in an integrated manner to prevent stratification at the joint position.

[0078] The specific method for performing cement interlocking restoration and covering protection treatment in step S9 is: confirming the fixed position of the submarine cable, cleaning the silt and debris at the fixed position, fixing the cement interlocking at the corresponding position, and then fixing the submarine cable tightly against the cement interlocking, and finally setting a protective layer on the surface of the submarine cable; the protective layer is concrete or other covering materials, and the protective layer is evenly set on the surface of the submarine cable.

[0079] The above fixing position should be the same as the original fixing position as much as possible, so that the operation can be carried out on the base of the original cement joint, which can effectively reduce the amount of sludge cleaning and thus reduce the working hours. After the cement joint is fixed, the new submarine cable can be fixed and P·F type fast-hardening silicate cement can be used. The fine aggregate is natural river sand (the particle size range is controlled at 0.15-5mm), the coarse aggregate is 5-20mm crushed stone or sand and gravel, calcium aluminate is added as a quick-setting agent, and fly ash and slag powder are used for blending. The concrete is placed in a submersible tank and a conduit. The cement formula has better corrosion resistance in seawater than ordinary distribution, and is more conducive to the fixing of submarine cables than ordinary materials; if greater construction strength and corrosion resistance are required, polymer fibers can be used for pre-embedded skeletons and anti-corrosion treatment can be performed on the surface of the concrete pile.

[0080] The method for the handover test in step S10 is: after the installation is completed and the protection measures are restored, preliminary functional testing, abnormal problem correction, system-level testing and test data handover are carried out in sequence.

[0081] The preliminary functional test at least includes insulation resistance test and DC withstand voltage test, the system-level test at least includes AC withstand voltage test, impact test and signal transmission test, and the test data at least includes test date, test equipment, test data and conclusion. During the test, attention should be paid to the integrity and accuracy of the signal and data, and efforts should be made to reduce signal attenuation and distortion.

[0082] The specific embodiments described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for repairing a submarine cable, characterized in that The following steps are involved: S1: Drive the DP positioning ship to the laying location, clean the submarine cable and cover it with cement strips for protection; S2: Cut the cable at the fault point, bundle the submarine cable and salvage the submarine cable end to the cable laying vessel; S3: Remove the submarine cable anchoring device and pull the submarine cable to the wind turbine; S4: Cut off the submarine cable protection point and recycle the protection device of the submarine cable protection point inside and outside the wind turbine. During the recycling process, reserve the pulling wire on the wind turbine; S5: Connect the pulling wire to the new submarine cable protection device and the submarine cable, pull the submarine cable to the set position of the wind turbine, and then install the anchoring device; S6: Measure the water depth, the length required for making the submarine cable joint, and cut the submarine cable; S7: making joints; S8: lowering the submarine cable; S9: Perform cement joint restoration and cover protection treatment on the submarine cable; S10: Perform handover test.

2. A method for repairing a submarine cable according to claim 1, characterized in that: The method for cleaning the cement bundling protection covering the submarine cable in step S1 is: a diver dives to the laying location, removes the silt covering the submarine cable in the area until the damaged location of the cable is exposed, and then further cleans the damaged location until the debris covering the cable at the damaged location is removed.

3. A method for repairing a submarine cable according to claim 1, characterized in that: The specific method for cutting off the fault point in step S4 is: the diver cuts the submarine cable at the fault point, then ties the submarine cable end to the ship crane, and then uses the crane to salvage the submarine cable to the cable laying ship; after the cutting process, the cable at the wind turbine end is waterproofed.

4. A method for repairing a submarine cable according to claim 3, characterized in that: During the cutting process of the submarine cable protection point, the diver dives to the corresponding position of the submarine cable protection device to complete the cutting. Then the personnel in the wind turbine and the diver connect the cut protection joint to the crane respectively, and use the crane to pull the split parts to the designated position for transfer. After the diver connects the cut protective joint to the crane, he fixes the pulling wire extending from the wind turbine to the position where the wind turbine's submarine cable extends, and performs a preliminary fixation to prevent it from falling off in preparation for the next step of traction setting.

5. A method for repairing a submarine cable according to claim 1, characterized in that: In step S5, the method for connecting the new submarine cable protection device and the submarine cable by pulling the steel wire is as follows: when the cable-laying vessel travels close to the wind turbine, a temporary fixing point is set under the cable-laying vessel, and after the underwater pulling device with a waterproof function is placed at the temporary fixing point, the pulling steel wire of the underwater pulling device is connected to the new submarine cable, and the underwater pulling device pulls the new cable and connects the new cable to the wind turbine.

6. A method for repairing a submarine cable according to claim 1, characterized in that: The method for measuring the water depth and confirming the required length of the submarine cable joint in step S6 is: using sonar or depth meter to obtain water depth data, calculating the required submarine cable length according to the actual water depth of the submarine cable laying and the actual cable laying path, and setting the reserved amount to 5-10%.

7. A method for repairing a submarine cable according to claim 1, characterized in that: The method for making the joint in step S7 is: introducing the two ends of the submarine cables to be connected into a special joint making platform, stripping, cleaning, insulation treatment, material filling, sealing and mechanical strength measurement are carried out in a dry and clean environment, and then testing its electrical performance.

8. A method for repairing a submarine cable according to claim 1, characterized in that: The specific method for performing cement interlocking restoration and covering protection treatment in step S9 is: confirming the fixed position of the submarine cable, cleaning the silt and debris at the fixed position, fixing the cement interlocking at the corresponding position, and then fixing the submarine cable tightly against the cement interlocking, and finally setting a protective layer on the surface of the submarine cable; the protective layer is concrete or other covering materials, and the protective layer is evenly set on the surface of the submarine cable.

9. A method for repairing a submarine cable according to claim 1, characterized in that: The method for the handover test in step S10 is: after the installation is completed and the protection measures are restored, preliminary functional testing, abnormal problem correction, system-level testing and test data handover are carried out in sequence.

10. A method for repairing a submarine cable according to claim 9, characterized in that: The preliminary functional test includes at least an insulation resistance test and a DC withstand voltage test, the system-level test includes at least an AC withstand voltage test, an impact test and a signal transmission test, and the test data includes at least a test date, test equipment, test data and conclusion.

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