Impressed Current Cathodic Protection System for Offshore Wind Power Foundation Piles

Abstract

The present invention discloses an impressed current cathodic protection system for an offshore wind power pile foundation, which comprises a wind power pile foundation, a potentiostat, a composite cable, a reference electrode assembly and an auxiliary anode. The composite cable is arranged on one side of the wind power pile foundation. The composite cable penetrates through the reference electrode assembly and the auxiliary anode which are arranged at intervals, and the composite cable is coaxially connected with the reference electrode assembly and the auxiliary anode. The composite cable comprises a plurality of core wires and a plurality of branching points. One end of the core wire branches out at the branching point to be connected with the reference electrode assembly or the auxiliary anode, and the other end of the core wire is connected with the potentiostat. The present invention overcomes the problems that the current system can only be pre-installed on a newly built platform, is easily damaged by wind and wave impacts, and has high repair costs, and improves the reliability of the system.

Description

Technical Field

[0001] The present invention relates to the technical field of corrosion and protection, and particularly to an impressed current cathodic protection system for an offshore wind power pile foundation. Background Art

[0002] With the increasing saturation of onshore wind resource utilization, developing clean energy represented by offshore wind power has become a long-term strategy for countries to cope with future energy and climate change. Offshore wind power operates in a complex marine environment and is affected by factors such as wind loads, waves, and water currents. Moreover, the offshore wind power platform is in an unattended state. Therefore, the corrosion protection of offshore wind power pile foundations is of great significance to their safe operation.

[0003] Currently in China, the protection of underwater steel structures of offshore wind power generally adopts a fixed cathodic protection method, that is, sacrificial anodes or fixed impressed current cathodic protection systems or both are pre-installed on the newly built pile cages. Since the current offshore wind farms are mainly located in offshore areas, the dissolution of sacrificial anodes may cause certain pollution to the sea area; the underwater welding, replacement, and repair technologies of sacrificial anodes are difficult, risky, and expensive. The auxiliary anodes of the fixed impressed current cathodic protection system are easily damaged during transportation and installation; during the period from the underwater installation of the wind power pile foundation to the completion of the installation of other equipment on the platform, since the impressed current system is not operating, the auxiliary anodes are easily affected by biological fouling; the underwater maintenance and replacement of fixed auxiliary anodes are extremely difficult. Summary of the Invention

[0004] In order to overcome the disadvantages and deficiencies existing in the prior art, the purpose of the present invention is to provide an impressed current cathodic protection system for an offshore wind power pile foundation, to overcome the problems that the current system can only be pre-installed on a newly built platform, is easily damaged by wind and waves, and has high repair costs, and to improve the reliability of the system.

[0005] The purpose of the present invention is achieved by the following technical solutions:

[0006] An impressed current cathodic protection system for an offshore wind power pile foundation includes a wind power pile foundation, a potentiostat, a composite cable, a reference electrode assembly, and an auxiliary anode. The composite cable is arranged on one side of the wind power pile foundation. The composite cable passes through the reference electrode assembly and the auxiliary anode arranged at intervals, and the composite cable is coaxially connected to the reference electrode assembly and the auxiliary anode. The composite cable includes a plurality of core wires and a plurality of branching points. One end of the core wire branches out at the branching point and is connected to the reference electrode assembly or the auxiliary anode, and the other end of the core wire is connected to the potentiostat.

[0007] In one embodiment, it further includes a gravity base. The wind power pile foundation is installed on one side of the berthing member. The composite cable is arranged between the wind power pile foundation and the berthing member. One end of the composite cable is connected to the berthing member, and the other end of the composite cable is connected to the gravity base, and the gravity base is placed on the seabed.

[0008] In one embodiment, the gravity base is of a split structure and includes a plurality of concrete modules. The plurality of concrete modules are evenly distributed on the seabed by being connected with anchor chains.

[0009] In one embodiment, the composite cable further includes a steel wire rope, and a plurality of core wires are wound around the steel wire rope; a functional core wire layer, a first protective layer, and a second protective layer are sequentially arranged outside the steel wire rope, and the plurality of core wires are located in the functional core wire layer.

[0010] In one embodiment, the auxiliary anode includes an anode housing. The composite cable penetrates and is coaxially connected to the anode housing. At least one wiring terminal is fixed on the inner wall of the anode housing, and one wiring terminal is correspondingly connected to one core wire.

[0011] In one embodiment, there are a plurality of the wiring terminals, and the plurality of wiring terminals are welded to the inner wall of the anode housing.

[0012] In one embodiment, the anode housing includes an anode barrel and a first sealing cover. The anode barrel is a cylindrical structure with openings at both ends. First sealing covers are provided at the openings at both ends of the anode barrel. The composite cable passes through the two first sealing covers, and a plurality of the wiring terminals are fixed on the inner wall of the anode barrel; a first injection hole is provided on the first sealing cover, and a first sealing filler is injected into the anode housing through the first injection hole, and the first sealing filler fills the gap between the composite cable and the anode housing.

[0013] In one embodiment, the reference electrode member includes a reference housing and two reference electrodes. The composite cable penetrates and is coaxially connected to the reference housing. The two reference electrodes are symmetrically arranged along the axial direction on both sides of the reference housing, and the two core wires respectively pass through the reference housing and are correspondingly connected to the two reference electrodes one by one.

[0014] In one embodiment, the reference electrode includes an insulating sleeve and a core. The insulating sleeve is fixed on the outside of the reference housing, the core is installed in the insulating sleeve, and the core wire is correspondingly connected to the core one by one.

[0015] In one embodiment, the reference housing includes a fixed tube and a second sealing cover. The fixed tube is a cylindrical structure with openings at both ends, and the second sealing cover is provided at each opening of the fixed tube. The composite cable passes through the two second sealing covers. The second sealing cover is provided with a second injection hole, and a second sealing filler is injected into the reference housing through the second injection hole. The second sealing filler fills the gap between the composite cable and the reference housing.

[0016] The beneficial effects of the present invention are as follows: The reference electrode element and the auxiliary anode are arranged at intervals on the composite cable, and the reference electrode element and the auxiliary anode are coaxially connected to the composite cable, so that the force distribution of the composite cable is more uniform, reducing the mechanical impact at the connection between the composite cable and the auxiliary anode and the reference electrode element under the impact of water flow or the shaking of the composite cable, and improving the service safety of the composite cable; overcoming the problems that the impressed current system for offshore wind power piles can only be pre-installed on a newly built platform at present, is vulnerable to the impact and damage of wind and waves, and has high repair costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention, and therefore should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can be obtained based on these drawings without creative efforts.

[0018] Figure 1 is a schematic structural diagram of the impressed current cathodic protection system according to the embodiment of the present invention;

[0019] Figure 2 is a schematic structural diagram of the composite cable according to the embodiment of the present invention;

[0020] Figure 3 is a schematic structural diagram of the auxiliary anode according to the embodiment of the present invention;

[0021] Figure 4 is a schematic structural diagram of the reference electrode element according to the embodiment of the present invention;

[0022] Figure 5 is Figure 4 a schematic structural diagram of the reference electrode in

[0023] In the figure: 1. Wind power pile foundation; 11. Wind power pile tower barrel; 12. Top platform; 13. First-floor ring beam; 14. Second-floor ring beam; 15. Third-floor ring beam; 2. Potentiostat; 3. Composite cable; 31. Steel wire rope; 32. Core wire; 321. Signal core wire; 322. Power core wire; 33. Branch point; 3A. Functional core wire layer; 3B. First protective layer; 3C. Second protective layer; 4. Auxiliary anode; 41. Anode housing; 411. Anode barrel; 412. First sealing cover; 4121. First injection hole; 42. Wiring terminal; 43. First sealing filler; 44. Sealing gasket; 5. Reference electrode component; 51. Reference housing; 511. Fixed tube; 512. Second sealing cover; 5121. Second injection hole; 52. Reference electrode; 521. Insulating sleeve; 5221. Opening; 522. Pole core; 5221. Lead terminal; 523. Top cover; 524. Fixed bolt; 53. Conduit; 54. Second sealing filler; 55. Anti-disengagement boss; 56. Card slot; 57. Tightening bolt; 58. Waterproof connector; 6. Gravity foundation; 7. Berthing piece; 8. Tensioning unit. Specific embodiments

[0024] The following will describe in detail specific embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the description of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts shall fall within the scope of protection of the present invention.

[0025] In the description of the present invention, unless otherwise clearly defined and limited, terms such as "set", "installed", "connected", etc. shall be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms can be understood according to specific circumstances.

[0026] The orientation or positional relationship indicated by terms such as "upper", "lower", "left", "right", "front", "rear", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the product of the present invention is usually placed during use. It is only for the convenience of description and simplification of the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention.

[0027] Terms such as "first", "second", "third", etc. are only used to distinguish elements with similar attributes, rather than indicating or implying relative importance or a specific order.

[0028] The term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, including not only those elements listed, but also other elements not specifically listed.

[0029] The present invention provides an impressed current cathodic protection system for an offshore wind power pile foundation, as Figure 1 shown, which includes a wind power pile foundation 1, a potentiostat 2, a composite cable 3, a reference electrode component 5 and an auxiliary anode 4. The composite cable 3 is arranged on one side of the wind power pile foundation 1. The composite cable 3 passes through the reference electrode component 5 and the auxiliary anode 4 arranged at intervals, that is, the reference electrode component 5 and the auxiliary anode 4 are fixedly arranged on the composite cable 3 at intervals, and the composite cable 3 is coaxially connected with the reference electrode component 5 and the auxiliary anode 4; the composite cable 3 includes a plurality of core wires 32 and a plurality of branch points 33. One end of the core wire 32 branches out at the branch point 33 to be connected with the reference electrode component 5 or the auxiliary anode 4, and the other end of the core wire 32 is connected with the potentiostat 2. Both the reference electrode component 5 and the auxiliary anode 4 are electrically connected with the potentiostat 2 through different core wires 32. In this embodiment, by coaxially arranging and connecting the composite cable 3 with the reference electrode component 5 and the auxiliary anode 4, the force distribution of the composite cable 3 is made more uniform, reducing the mechanical impact at the connection between the composite cable 3 and the auxiliary anode 4 and the reference electrode component 5 under the condition of water flow impact or the shaking of the composite cable 3, and improving the service safety of the composite cable 3; overcoming the problems that the existing impressed current system for offshore wind power piles can only be pre-installed on a newly built platform, is vulnerable to damage by wind and waves, and has high repair costs.

[0030] Specifically, as Figures 1 to 4 shown, the composite cable 3 is arranged at an interval from the wind power pile foundation 1 to avoid the problem that the auxiliary anode 4 installed on the composite cable 3 is too close to the wind power pile foundation 1, which is likely to cause overprotection of local steel structures. The composite cable 3 includes a plurality of core wires 32. According to the installation positions of the auxiliary anode 4 and the reference electrode component 5, a plurality of branch points 33 are provided on the composite cable 3, so that one end of the core wire 32 branches out at the corresponding branch point 33 to be connected with the corresponding auxiliary anode 4 or the reference electrode component 5, and the other end of the core wire 32 is connected with the potentiostat 2. The potentiostat 2 is connected to an external power supply and the wind power pile foundation 1 through a wire, or the potentiostat 2 is provided with an internal power supply. During operation, the cathodic protection system adjusts the current output of the auxiliary anode 4 in real time according to the working potential of the wind power pile foundation 1 detected by the reference electrode component 5 to achieve cathodic protection of the wind power pile foundation 1.

[0031] Among them, along the length direction of the composite cable 3, a plurality of auxiliary anodes 4 and reference electrode components 5 can be installed, and the installation positions and quantities of the auxiliary anodes 4 and reference electrode components 5 are determined according to the exposed area of the wind power pile foundation 1 and environmental parameters. A wind power pile tower barrel 11 is installed at the top of the wind power pile foundation 1, and the potentiostat 2 is installed inside the wind power pile tower barrel 11. Since the tower barrel contains environmental control equipment, it can reduce the corrosion of the potentiostat 2 by the marine atmosphere, etc., and improve its operation stability. From top to bottom, the upper end of the wind power pile foundation 1 is also successively provided with a top layer platform 12, a first layer ring beam 13, a second layer ring beam 14, and a third layer ring beam 15.

[0032] As an implementation manner, as Figure 1 shown, the impressed current cathodic protection system further includes a gravity foundation 6. The wind power pile foundation 1 is installed on one side of the berthing member 7. The composite cable 3 is arranged between the wind power pile foundation 1 and the berthing member 7. One end of the composite cable 3 is connected to the berthing member 7, and the other end of the composite cable 3 is connected to the gravity foundation 6. The gravity foundation 6 is placed on the seabed. Among them, the composite cable 3 is connected to the berthing member 7 through a tensioning unit 8. The berthing member 7 includes a berthing member platform. The upper end of the tensioning unit 8 is fixed inside the berthing member platform, and the lower end of the tensioning unit 8 is connected to the top end of the composite cable 3. The composite cable 3 is suspended between the berthing member 7 and the wind power pile foundation 1. The upright column of the berthing member 7 can effectively prevent the maintenance ship from colliding with and scraping the composite cable 3. The end of the composite cable 3 is connected to the gravity foundation 6, and the gravity foundation 6 is placed on the seabed to realize the fixation of the composite cable 3.

[0033] As an implementation manner, as Figure 1 shown, the gravity foundation 6 is of a split structure and includes a plurality of concrete modules. The plurality of concrete modules are evenly distributed on the seabed through chain connections, can adapt to the complex seabed terrain, effectively anchor the composite cable 3, and resist the impact of ocean currents.

[0034] As an implementation manner, as Figure 2 shown, the composite cable 3 further includes a steel wire rope 31, and a plurality of core wires 32 are wound around the steel wire rope 31; a functional core wire layer 3A, a first protective layer 3B, and a second protective layer 3C are successively arranged outside the steel wire rope 31, and a plurality of core wires 32 are located in the functional core wire layer 3A. Specifically, the core wire 32 includes a power core wire 322 and a signal core wire 321. The power core wire 322 and the signal core wire 321 are located in the functional core wire layer 3A. A water-blocking material is added between the core wires 32 to ensure the radial water-blocking property of the composite cable 3. The power core wire 322 is electrically connected to the auxiliary anode 4, and the signal core wire 321 is electrically connected to the reference electrode component 5. The system adjusts the current output of the auxiliary anode 4 in real time according to the working potential of the wind power pile foundation 1 detected by the reference electrode component 5 to realize the cathodic protection of the wind power pile foundation 1. The power core wire 322 adopts a single-core wire 32, and its cross-sectional area is related to the maximum output current of the auxiliary anode 4; since there is no large current passing through the signal core wire 321, in order to ensure that the potential signal is not interfered, the signal core wire 321 is provided with a shielding layer.

[0035] Among them, the tensile steel wire rope 31 is located at the center of the composite cable 3. The steel wire rope 31 adopts an anti-rotation structure, and the surface of the steel wire rope 31 is a galvanized layer. A first protective layer 3B and a second protective layer 3C are sequentially arranged outside the functional core wire layer 3A. The first protective layer 3B is a polyethylene (PE) layer, which can prevent seawater penetration and mechanical damage; the second protective layer 3C is a PVDF layer, which can prevent the corrosion of the composite cable 3 by sodium hypochlorite generated by the auxiliary anode 4. In addition, the PVDF layer has certain high-temperature resistance and wear resistance, and can also prevent marine biofouling, avoid biological attachment caused by the long-term immersion of the composite cable 3 in seawater, and reduce the load of the composite cable 3.

[0036] As an implementation manner, as Figure 3 shown, the auxiliary anode 4 includes an anode housing 41. The composite cable 3 passes through and is coaxially connected to the anode housing 41. At least one terminal 42 is fixed on the inner wall of the anode housing 41, and one terminal 42 is correspondingly connected to one core wire 32. Specifically, the composite cable 3 passes through at the central axis of the anode housing 41, realizing the coaxial arrangement of the composite cable 3 and the auxiliary anode 4. Compared with the current off-axis design where the center of gravity of the auxiliary anode 4 is located on one side of the composite cable 3, under the action of water flow impact, the impact force of the auxiliary anode 4 on the composite cable 3 can be effectively reduced.

[0037] As an implementation manner, as Figure 3 shown, there are multiple terminals 42. The multiple terminals 42 are welded to the inner wall of the anode housing 41, and the multiple terminals 42 are correspondingly connected to the same number of core wires 32 one by one. Multiple terminals 42 are welded inside the auxiliary anode 4 to increase the number of strands of the connectable wire; on the premise of meeting the current output requirements, the selection of the power core wire 322 of the composite cable 3 can be optimized, effectively reducing the wire diameter of the composite cable 3, thereby reducing the impact force of the water flow. The design of the auxiliary anode 4 in this embodiment can obtain a larger anode surface area and improve the anode drainage capacity.

[0038] As an implementation manner, as Figure 3As shown in the figure, the anode housing 41 includes an anode barrel 411 and a first sealing cover 412. The anode barrel 411 is a cylindrical structure with openings at both ends. First sealing covers 412 are provided at the openings at both ends of the anode barrel 411. The composite cable 3 passes through the two first sealing covers 412. A plurality of wiring terminals 42 are fixed on the inner wall of the anode barrel 411. A first injection hole 4121 is provided on the first sealing cover 412. Through the first injection hole 4121, a first sealing filler 43 is injected into the anode housing 41. The first sealing filler 43 fills the gap between the composite cable 3 and the anode housing 41, playing a role in sealing the connection between the composite cable 3 and the anode housing 41. Among them, the anode barrel 411 is made of a metal material, and its surface is coated with a metal oxide, preferably a noble metal oxide. A sealing gasket 44 is also provided between the composite cable 3 and the anode barrel 411 and the first sealing cover 412. The sealing gasket 44 is a wedge-shaped structure. The sealing gasket 44 is sleeved on the composite cable 3. When the first sealing cover 412 is tightened, the wedge-shaped sealing gasket 44 is continuously compressed to complete the sealing between the first sealing cover 412 and the composite cable 3.

[0039] Among them, the first sealing filler 43 in the gap between the anode housing 41 and the composite cable 3 is made of the same material as the outer sheath of the composite cable 3, that is, the first sealing filler 43 is the same as the material of the second protective layer 3C. PVDF can be selected. Through re-vulcanization, the first sealing filler 43 is completely integrated with the composite cable 3, ensuring watertightness. At the same time, when the composite cable 3 shakes, the auxiliary anode 4 does not fall off.

[0040] Specifically, when the auxiliary anode 4 is fixed on the composite cable 3, the anode barrel 411 of the noble metal oxide MMO and the first sealing covers 412 at both ends are installed near the branching point 33 of the power core wire 322 of the composite cable 3. The power core wire 322 led out from the branching point 33 is connected to the wiring terminal 42 of the auxiliary anode 4. The two first sealing covers 412 are tightened. The wedge-shaped sealing gasket 44 installed between the first sealing cover 412 and the composite cable 3 is continuously compressed as the first sealing cover 412 is tightened to complete the sealing between the first sealing cover 412 and the composite cable 3. Through the first injection hole 4121, the first sealing filler 43 is injected into the cavity between the anode housing 41 and the composite cable 3. The material of the first sealing filler 43 is the same as that of the outermost second protective layer 3C of the composite cable 3. Through re-vulcanization, it is integrated with the composite cable 3, ensuring both the watertightness of the connection between the power core wire 322 of the composite cable 3 and the auxiliary anode 4 and avoiding relative displacement between the composite cable 3 and the auxiliary anode 4. The wiring terminal 42 being embedded in the first sealing filler 43 can prevent the longitudinal detachment of the auxiliary anode 4. The number of wiring terminals 42 can be set according to the number of power core wires 322.

[0041] As an implementation method, as Figure 4As shown in the figure, the reference electrode component 5 includes a reference housing 51 and two reference electrodes 52. The composite cable 3 passes through and is coaxially connected to the reference housing 51. The two reference electrodes 52 are symmetrically arranged along the axial direction on both sides of the reference housing 51, and the two core wires 32 respectively pass through the reference housing 51 and are connected to the two reference electrodes 52 in one-to-one correspondence. The two reference electrodes 52 are symmetrically distributed on both sides of the composite cable 3, realizing the coaxial arrangement of the reference electrode component 5 and the composite cable 3. Under the action of water flow impact, the impact force of the reference electrode component 5 on the composite cable 3 can be effectively reduced, and the service life can be improved. The two reference electrodes 52 are respectively a high-purity zinc reference electrode component 5 and an Ag / AgCl reference electrode component 5, and the working potential of the wind power pile foundation 1 is detected by the two reference electrode components 5 to improve the accuracy of the detection data.

[0042] As an implementation manner, as Figure 4 and Figure 5 shown, the reference electrode 52 includes an insulating sleeve 521 and a core 522. The insulating sleeve 521 is fixed on the outer side of the reference housing 51, and the core 522 is installed in the insulating sleeve 521. The core wire 32 is connected to the core 522 in one-to-one correspondence. Among them, the core 522 is installed in the insulating sleeve 521 to avoid the core 522 colliding with the outside during the installation process; a plurality of openings 5211 are provided on the outer side surface of the insulating sleeve 521, so that the core 522 can communicate with the seawater medium. The core 522 includes a lead terminal 5221, and the lead terminal 5221 is fixed to the top of the core 522 via a fixing bolt 524; the reference electrode 52 further includes a top cover 523, the top cover 523 is bolted to the top end of the insulating sleeve 521, and the lead terminal 5221 passes through the top cover 523 and is connected to the core wire 32.

[0043] As an implementation manner, as Figure 4 shown, the reference electrode component 5 further includes a card slot 56 and a tightening bolt 57. The card slot 56 is fixed on the outer side of the reference housing 51, the bottom of the insulating sleeve 521 is installed in the card slot 56, and the tightening bolt 57 is threadedly connected to the card slot 56. When the reference electrode 52 fails or is consumed, the core 522 of the failed reference electrode 52 can be replaced by loosening the tightening bolt 57.

[0044] As an implementation manner, as Figure 4 shown, the reference electrode component 5 further includes a conduit 53. The conduit 53 communicates the insulating sleeve 521 and the reference housing 51, and the core wire 32 passes through the reference housing 51 and the conduit 53 in sequence and is connected to the core 522.

[0045] As an implementation manner, as Figure 4As shown, the reference electrode component 5 further includes a waterproof connector 58. The waterproof connector 58 is installed at the top of the insulating sleeve 521. The lower end of the conduit 53 is connected to the waterproof connector 58, such that the core wire 32 sequentially passes through the branching point 33 of the composite cable 3, the reference housing 51, the conduit 53 and is connected to the waterproof connector 58. The lead terminal 5221 of the core electrode 522 is also connected to the waterproof connector 58, realizing the electrical connection between the reference electrode 52 and the core wire 32.

[0046] As an implementation, as Figure 4 shown, the reference housing 51 includes a fixed tube 511 and a second sealing cover 512. The fixed tube 511 is a cylindrical structure with openings at both ends. Second sealing covers 512 are provided at the openings at both ends of the fixed tube 511, and the composite cable 3 passes through the two second sealing covers 512. A second injection hole 5121 is provided on the second sealing cover 512. Through the second injection hole 5121, a second sealing filler 54 is injected into the reference housing 51. The second sealing filler 54 fills the gap between the composite cable 3 and the reference housing 51, realizing the sealing of the connection between the composite cable 3 and the reference housing 51. Among them, the fixed tube 511 can be the fixed tube 51. The material of the second sealing filler 54 is the same as that of the second protective layer 3C on the outermost layer of the composite cable 3. Through re-vulcanization, it is integrated with the composite cable 3, ensuring both the watertightness of the connection between the signal core wire 321 of the composite cable 3 and the reference electrode component 5 and avoiding relative displacement between the composite cable 3 and the reference electrode component 5. An anti-detachment boss 55 is further provided on the inner wall of the fixed tube 511. The anti-detachment boss 55 is integrated with the second sealing filler 54 to prevent it from falling off.

[0047] Further, in this embodiment, the reference housing 51, the reference electrode 52 and the anode housing 41 are all cylindrical structures.

[0048] Specifically, the second sealing cover 512 and the fixing tube 51 of the reference electrode assembly 5 are sequentially inserted into the composite cable 3 and moved to the branching point 33 of the signal core wire 321 of the composite cable 3. The signal core wire 321 of the composite cable 3 is introduced into the wire threading tube 53 on the side of the fixing tube 51 of the reference electrode assembly 5, and the signal core wire 321 is connected to one end of the waterproof joint 58. The core 522 of the reference electrode 52 is inserted from the bottom end of the reference electrode 52. After the lead terminal 5221 of the core 522 of the reference electrode 52 is tightly connected to the waterproof joint 58, the tightening bolt 57 is tightened, the second sealing cover 512 is screwed tightly, and the second sealing filler 54 is filled through the second injection hole 5121 to complete the sealing of the reference electrode assembly 5 and the composite cable 3. The material of the second sealing filler 54 is the same as that of the second protective layer 3C of the composite cable 3. Through re-vulcanization, it is integrated with the composite cable 3, which not only ensures the watertightness of the connection between the signal core wire 321 of the composite cable 3 and the reference electrode assembly 5, but also avoids relative displacement between the composite cable 3 and the reference electrode assembly 5. The anti-detachment boss 55 in the fixing tube 51 is integrated with the second sealing filler 54 to prevent it from falling off. When the reference electrode 52 fails or is consumed, the core 522 of the failed reference electrode 52 can be replaced by loosening the tightening bolt 57.

[0049] Compared with the prior art, the beneficial effects of the present invention include:

[0050] 1. The upper end of the tensioned composite cable 3 is fixed to the inner side of the berthing member platform of the offshore wind power cage. The composite cable 3 is protected by the column of the berthing member 7, which can effectively avoid the collision and scratching of the offshore wind power operation and maintenance ship, and at the same time reduce the impact of the offshore wind and waves on the composite cable 3, greatly improving the system safety.

[0051] 2. The gravity foundation 6 adopts a split structure. During the piling process of the platform pile foundation, it will cause damage to the adjacent seabed. At the same time, the erosion of the ocean current will make the seabed topography near the pile foundation more complex. Adopting a split structure can adapt to the complex seabed topography around the platform pile foundation of the offshore platform and provide a stable anchorage for the tensioning system.

[0052] 3. The tensioned impressed current system uses an auxiliary anode 4 coaxial with the composite cable 3. Compared with the current non-coaxial design (the center of gravity of the auxiliary anode is on one side of the composite cable), under the action of water flow impact, the impact force of the auxiliary anode 4 on the composite cable 3 can be effectively reduced. Secondly, a plurality of terminal blocks 42 are welded inside the auxiliary anode 4 to increase the number of strands of connectable wires. On the premise of meeting the current output requirements, the selection of the power core wire 322 of the composite cable 3 can be optimized, effectively reducing the wire diameter of the composite cable 3, thereby reducing the impact force of the water flow. Compared with the split design, the auxiliary anode 4 design of this patent can obtain a larger anode surface area and improve the anode drainage capacity. The sealing material for the gap between the auxiliary anode 4 and the composite cable 3 is made of the same material as the outer sheath of the composite cable 3. Through re-vulcanization, the sealing material is completely integrated with the composite cable 3 to ensure watertightness. At the same time, when the composite cable 3 shakes, the auxiliary anode 4 does not fall off.

[0053] 4. The tensioned impressed current system uses a reference anode coaxial with the composite cable 3. Two solid reference electrodes 52 are symmetrically distributed on both sides of the composite cable 3 to achieve the coaxial arrangement of the reference electrode assembly 5 and the composite cable 3. Compared with the split design, under the action of water flow impact, the impact force of the reference electrode assembly 5 on the composite cable 3 can be effectively reduced, and the service life can be improved. Secondly, the core 522 of the reference electrode 52 can be replaced underwater, reducing the maintenance difficulty. Usually, if the reference electrode 52 fails or is consumed, it is necessary to recover the tensioned composite cable 3 to replace the reference electrode 52, or even replace the entire composite cable 3. In this design, the reference electrodes 52 are symmetrically distributed on both sides of the composite cable 3 and are connected to the power core wire 322 of the composite cable 3 through waterproof connectors 58. Once the reference electrode 52 fails, it can be quickly replaced underwater, avoiding the recovery and replacement of the composite cable 3 and increasing the convenience of maintenance. The sealing material for the gap between the reference electrode assembly 5 and the composite cable 3 is made of the same material as the outer sheath of the composite cable 3. Through re-vulcanization, the sealing material is completely integrated with the composite cable 3 to ensure watertightness. At the same time, when the composite cable 3 shakes, the reference electrode assembly 5 does not fall off.

[0054] Example 1

[0055] During the installation process, welding construction is not adopted, and the existing components of the wind power pile foundation 1 are not damaged. The fixed point of the tensioning unit 8 is installed below the berthing platform. By installing a U-shaped clamp on the cross beam of the berthing platform and installing a lead screw below the U-shaped clamp, the upper end of the tensioning unit 8 is installed on the lead screw, and the movement of the tensioning unit 8 is restricted by a limit nut. The lower end of the composite cable 3 is fixed to the seabed through a split gravity foundation 6. Currently, the system operates stably, the auxiliary anode 4 and the reference electrode assembly 5 operate normally, and the protection potential of the wind power pile foundation 1 meets the cathodic protection design specifications.

[0056] The above are only the preferred embodiments of the present invention, and do not impose any formal limitations on the present invention. Although the present invention has been disclosed above with the preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some changes or modifications using the above-disclosed technical content within the scope of the technical solution of the present invention, which are equivalent embodiments of equivalent changes. However, as long as it does not depart from the technical solution content of the present invention, any simple modification, equivalent change and modification made to the above embodiments based on the technical essence of the present invention still fall within the protection scope of the technical solution of the present invention.

Claims

1. An impressed current cathodic protection system for offshore wind power pile foundation, characterized in that: The invention comprises a wind power pile foundation (1), a constant potential instrument (2), a composite cable (3), a reference electrode (5) and an auxiliary anode (4), wherein the composite cable (3) is arranged on one side of the wind power pile foundation (1), the composite cable (3) passes through the reference electrode (5) and the auxiliary anode (4) arranged at intervals, and the composite cable (3) is coaxially connected with the reference electrode (5) and the auxiliary anode (4); the composite cable (3) comprises a plurality of core wires (32) and a plurality of branching points (33), one end of the core wire (32) is branched at the branching point (33) and connected to the reference electrode (5) or the auxiliary anode (4), and the other end of the core wire (32) is connected to the constant potential instrument (2); The reference electrode member (5) comprises a reference shell (51) and two reference electrodes (52); the composite cable (3) is passed through and coaxially connected to the reference shell (51); the two reference electrodes (52) are symmetrically arranged on both sides of the reference shell (51) along the axial direction; and the two core wires (32) respectively pass through the reference shell (51) and are connected to the two reference electrodes (52) in a one-to-one correspondence; The reference electrode (52) comprises an insulating sleeve (521) and a pole core (522), wherein the insulating sleeve (521) is fixed to the outside of the reference housing (51), the pole core (522) is installed in the insulating sleeve (521), and the core wire (32) is connected to the pole core (522) in a one-to-one correspondence; The reference shell (51) comprises a fixed tube (511) and a second sealing cover (512); the fixed tube (511) is a cylindrical structure with openings at both ends; the second sealing covers (512) are provided at the openings at both ends of the fixed tube (511); the composite cable (3) passes through the two second sealing covers (512); the second sealing cover (512) is provided with a second injection hole (5121); a second sealing filler (54) is injected into the reference shell (51) through the second injection hole (5121); the second sealing filler (54) fills the gap between the composite cable (3) and the reference shell (51).

2. The impressed current cathodic protection system for offshore wind power pile foundation according to claim 1, characterized in that: The impressed current cathodic protection system also includes a gravity foundation (6), the wind turbine pile foundation (1) is installed on one side of a mooring member (7), the composite cable (3) is arranged between the wind turbine pile foundation (1) and the mooring member (7), one end of the composite cable (3) is connected to the mooring member (7), and the other end of the composite cable (3) is connected to the gravity foundation (6), and the gravity foundation (6) is placed on the seabed.

3. The impressed current cathodic protection system for offshore wind power pile foundation according to claim 2, characterized in that: The gravity foundation (6) is a split structure, comprising a plurality of concrete modules, and the plurality of concrete modules are connected by anchor chains and evenly distributed on the seabed.

4. The impressed current cathodic protection system for offshore wind power pile foundation according to claim 1, characterized in that: The composite cable (3) further comprises a steel wire rope (31), wherein a plurality of core wires (32) are wrapped around the outside of the steel wire rope (31); a functional core wire layer (3A), a first protective layer (3B) and a second protective layer (3C) are sequentially arranged outside the steel wire rope (31), and the plurality of core wires (32) are located in the functional core wire layer (3A).

5. The impressed current cathodic protection system for offshore wind power pile foundation according to claim 1, characterized in that: The auxiliary anode (4) comprises an anode shell (41), the composite cable (3) is passed through and coaxially connected to the anode shell (41), at least one wiring terminal (42) is fixed on the inner wall of the anode shell (41), and one wiring terminal (42) is correspondingly connected to one core wire (32).

6. The impressed current cathodic protection system for offshore wind power pile foundation according to claim 5, characterized in that: There are a plurality of connection terminals (42), and the plurality of connection terminals (42) are welded to the inner wall of the anode shell (41).

7. The impressed current cathodic protection system for offshore wind power pile foundation according to claim 5, characterized in that: The anode shell (41) comprises an anode barrel (411) and a first sealing cover (412); the anode barrel (411) is a cylindrical structure with two ends open; the first sealing covers (412) are provided at the two end openings of the anode barrel (411); the composite cable (3) passes through the two first sealing covers (412); a plurality of connection terminals (42) are fixed on the inner wall of the anode barrel (411); the first sealing cover (412) is provided with a first injection hole (4121); a first sealing filler (43) is injected into the anode shell (41) through the first injection hole (4121); the first sealing filler (43) fills the gap between the composite cable (3) and the anode shell (41).

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