Submarine cable and offshore wind power system

Abstract

The invention relates to the technical field of offshore wind power generation, and provides a submarine cable and an offshore wind power system. The submarine cable comprises a cable core structure and an armor layer wrapping the outer side of the cable core structure, the armor layer is of a continuous wrapping structure formed by alternately arranging ferromagnetic metal wires and composite wires, the composite wires are of a metal core-armor insulation layer composite structure, the armor insulation layer tightly wraps the metal cores, and formation of induction current in the armor layer is blocked through the insulation isolation effect. According to the design of the armor layer, the characteristics of a ferromagnetic material are utilized, the requirements for high mechanical strength and low cost are met at the same time, and the cost defect of a traditional non-ferromagnetic material armor is avoided; the insulating layers of the composite wires and the ferromagnetic metal wires are alternately arranged, an induced current closed loop is thoroughly blocked, and compared with a traditional scheme of inserting an insulating part, the loss suppression effect is better. The three core requirements of low loss, high mechanical strength and low cost are synergistically optimized, submarine cable heating is reduced from the source, and the operation reliability is improved.

Description

Technical Field

[0001] This invention relates to the field of offshore wind power generation technology, and in particular to a submarine cable and an offshore wind power system. Background Technology

[0002] With the rapid development of the national economy, the demand for cross-water power transmission, such as interconnection between the mainland and islands and grid connection of offshore wind power, is becoming increasingly urgent. As a key core device, submarine cables directly affect the power supply quality of the power system due to their transmission capacity and operational stability. Currently, 220kV three-core AC submarine cables are still the mainstream product for ultra-high voltage cross-water power transmission, but they face the prominent technical problem of excessive armor loss in practical applications.

[0003] In existing technologies, two solutions are typically used to suppress eddy current losses in the armor layer of submarine cables: one is to replace the traditional armor steel wires with non-ferromagnetic materials such as copper wires and stainless steel. Although this can block induced currents to a certain extent, the cost of such materials is significantly higher than that of low-carbon steel, and their mechanical strength is difficult to adapt to the complex laying and operation conditions on the seabed; the other is to insert insulating components such as PE strips between the armor steel wires to separate the ferromagnetic regions. However, the insulating components themselves have weak mechanical properties and can only be inserted in small quantities, so the blocking effect on induced currents is limited and cannot fundamentally solve the loss problem.

[0004] At the same time, the armor layer of submarine cables needs to take into account both mechanical protection and loss control. Traditional solutions have always struggled to balance the contradictions between "low loss", "high mechanical strength" and "low cost", resulting in a large amount of heat generated by armor loss during submarine cable operation, which in turn limits the overall transmission capacity and fails to meet the growing demand for cross-water power transmission. Summary of the Invention

[0005] To address the aforementioned technical problems, this invention provides a submarine cable and an offshore wind power system.

[0006] In a first aspect, the present invention provides a submarine cable, comprising: a cable core structure; an armor layer covering the outside of the cable core structure, the armor layer comprising ferromagnetic metal wires and composite wires, the ferromagnetic metal wires and the composite wires being alternately arranged to form a continuous covering structure, the composite wires comprising a metal core and an armor insulation layer, the armor insulation layer covering the outside of the metal core for blocking the formation of induced current in the armor layer.

[0007] According to the present invention, a submarine cable has a core structure comprising: a conductive conductor for transmitting power; a first water-blocking structure covering the outside of the conductive conductor; an inner shielding layer covering the outside of the first water-blocking structure; a main insulation layer covering the outside of the inner shielding layer; an outer shielding layer covering the outside of the main insulation layer; a second water-blocking structure covering the outside of the outer shielding layer; a metal sheath covering the outside of the second water-blocking structure; and a semi-conductive sheath covering the outside of the metal sheath.

[0008] According to the present invention, a submarine cable has a plurality of cable core structures.

[0009] According to a submarine cable provided by the present invention, the submarine cable further includes: a filling layer disposed between each of the cable core structures; a wrapping tape wrapped around the outside of the filling layer; an inner lining layer covering the outside of the wrapping tape; and an outer sheath covering the outside of the armor layer.

[0010] According to a submarine cable provided by the present invention, the filling layer is a polyacetylene filling layer; the wrapping tape is a semi-conductive non-woven fabric wrapping tape; and the inner lining layer is a semi-conductive polyethylene inner lining layer. The filling layer, the wrapping tape, and the inner lining layer work together to form a continuous conductive path. One end of the conductive path is electrically connected to the metal sheath, and the other end is electrically connected to the armor layer, thereby achieving full-path grounding of the metal sheath and the armor layer.

[0011] According to a submarine cable provided by the present invention, the submarine cable further includes: at least one cooling pipe, each of the cooling pipes being synchronously twisted into the filling layer along with the cable core structure.

[0012] According to a submarine cable provided by the present invention, the submarine cable further includes a cooling circulation module, which is connected to each of the cooling pipes and is used to provide circulating coolant to the cooling pipes when the actual temperature of the submarine cable exceeds a preset temperature threshold.

[0013] According to the present invention, a submarine cable is provided, wherein the conductive conductor is a water-blocking copper conductor; the first water-blocking structure is a conductor water-blocking tape; the second water-blocking structure is a semi-conductive water-blocking tape; and the metal sheath is an alloy lead sheath. The water-blocking copper conductor, the conductor water-blocking tape, and the semi-conductive water-blocking tape work together to achieve water blocking throughout the entire route, and the alloy lead sheath, the filler layer, the wrapping tape, and the inner lining layer form the conductive path.

[0014] According to the present invention, the ferromagnetic metal wire is a galvanized low-carbon steel wire with an outer diameter of 5-7 mm; the metal core is a low-carbon steel core; the armor insulation layer is a polyurethane layer with an outer diameter of 4-6 mm.

[0015] A second aspect of the present invention provides an offshore wind power system comprising the submarine cable as described above.

[0016] The submarine cable provided by this invention includes a cable core structure and an armor layer covering the outside of the cable core structure. The armor layer is composed of ferromagnetic metal wires and composite wires, and the ferromagnetic metal wires and composite wires are arranged alternately to form a continuous covering structure. The composite wires are a composite structure of "metal core-armor insulation layer". The armor insulation layer tightly covers the outside of the metal core, and blocks the formation of induced current in the armor layer through insulation and isolation, thereby optimizing the operating performance of the armor layer.

[0017] This structural design employs an alternating arrangement of ferromagnetic metal wires and composite wires with a metal core and armor insulation layer to form a continuous covering structure. On one hand, both the ferromagnetic metal wires and the composite wires have ferromagnetic cores, ensuring the armor layer possesses high mechanical strength suitable for complex underwater laying conditions. Furthermore, the low cost of ferromagnetic materials avoids the high cost associated with traditional non-ferromagnetic armor. On the other hand, the metal core of the composite wires is covered by an armor insulation layer. This insulation layer, along with the alternating arrangement of the ferromagnetic metal wires, creates a continuous and comprehensive insulation barrier, completely blocking the closure of induced current within the armor layer. Compared to the traditional approach of inserting a small number of PE strips or other insulating components between the armored steel wires, this new circuit offers a more thorough suppression of eddy current losses, effectively addressing the limitations of traditional solutions in blocking induced currents. This technology achieves synergistic optimization of the three core requirements—low loss, high mechanical strength, and low cost—without sacrificing any of them. It fundamentally reduces the heating problem in submarine cables caused by armor losses, overcomes transmission capacity limitations, and reduces risks such as insulation aging and structural deformation due to high temperatures. This significantly improves the transmission capacity and long-term operational reliability of submarine cables, precisely meeting the needs of cross-water power transmission scenarios.

[0018] Furthermore, the offshore wind power system provided by this invention, since it includes the submarine cable as described above, also possesses the advantages described above. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in this invention 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 invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of the submarine cable provided by the present invention.

[0021] Reference numerals: 100, cable core structure; 110, conductive conductor; 120, first water-blocking structure; 130, inner shielding layer; 140, main insulation layer; 150, outer shielding layer; 160, second water-blocking structure; 170, metal sheath; 180, semi-conductive sheath; 200, armor layer; 210, ferromagnetic metal wire; 221, metal core; 222, armored insulation layer; 300, filling layer; 400, wrapping tape; 500, inner lining layer; 600, cooling pipe; 700, outer sheath. Detailed Implementation

[0022] The embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples. The following examples are for illustrative purposes only and should not be construed as limiting the scope of the invention.

[0023] In the description of the embodiments of the present invention, it should be noted that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of 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, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0024] In the description of the embodiments of the present invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of the present invention based on the specific circumstances.

[0025] In embodiments of the present invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0026] In the description of this specification, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Furthermore, without contradiction, those skilled in the art can combine and integrate different embodiments or examples and features of different embodiments or examples described in this specification to make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer. The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0027] The following is combined Figure 1 This invention describes a submarine cable and offshore wind power system provided by an embodiment of the present invention. It should be understood that the following description is merely an illustrative embodiment of the present invention and does not constitute any particular limitation on the present invention.

[0028] An embodiment of the first aspect of the present invention provides a submarine cable, such as Figure 1 As shown, it includes: a cable core structure 100; an armor layer 200, which covers the outside of the cable core structure 100. The armor layer 200 includes ferromagnetic metal wires 210 and composite wires. The ferromagnetic metal wires 210 and composite wires are arranged alternately to form a continuous covering structure. The composite wire includes a metal core 221 and an armor insulation layer 222. The armor insulation layer 222 covers the outside of the metal core 221 and is used to block the formation of induced current in the armor layer 200.

[0029] In other words, the submarine cable provided by the present invention includes a cable core structure 100 and an armor layer 200 covering the outside of the cable core structure 100. The armor layer 200 is composed of ferromagnetic metal wires 210 and composite wires, and the ferromagnetic metal wires 210 and composite wires are arranged alternately to form a continuous covering structure. The composite wire is a composite structure of "metal core 221-armor insulation layer 222". The armor insulation layer 222 tightly covers the outside of the metal core 221 and blocks the formation of induced current in the armor layer 200 through insulation and isolation, thereby optimizing the operating performance of the armor layer 200.

[0030] This structural design, employing alternating arrangements of ferromagnetic metal wires 210 and composite wires consisting of a metal core 221 and an armor insulation layer 222 to form a continuous covering structure, addresses several challenges. Firstly, both the ferromagnetic metal wires 210 and the metal core 221 of the composite wires are made of ferromagnetic material. This ensures the armor layer 200 possesses high mechanical strength suitable for complex underwater laying conditions, while the low cost of ferromagnetic materials avoids the high cost associated with traditional non-ferromagnetic armor. Secondly, the metal core 221 of the composite wires is covered by an armor insulation layer 222. This insulation layer, along with the alternating arrangement of the ferromagnetic metal wires 210, structurally forms a continuous and comprehensive insulation barrier, thoroughly... This technology blocks the closed loop of induced current in the armor layer 200. Compared with the traditional solution of inserting a small number of PE strips and other insulating components between the armor steel wires, it has a more thorough effect on suppressing eddy current loss and effectively solves the defect of limited effect of insulating components in blocking induced current in the traditional solution. This technical solution does not have to sacrifice any of the core requirements of "low loss", "high mechanical strength" and "low cost", and achieves synergistic optimization of the three. It reduces the heating problem of submarine cable caused by armor loss from the root, breaks through the limitation of transmission capacity, and reduces the risks of insulation aging and structural deformation caused by high temperature. It significantly improves the transmission capacity and long-term operational reliability of submarine cable and precisely meets the usage requirements of cross-water power transmission scenarios.

[0031] In one embodiment of the present invention, the ferromagnetic metal wire 210 is a galvanized low-carbon steel wire with an outer diameter of 5-7 mm; the metal core 221 is a low-carbon steel core; and the armored insulation layer 222 is a polyurethane layer with an outer diameter of 4-6 mm.

[0032] Specifically, the galvanized layer on the surface of the galvanized low-carbon steel wire forms a dense protective film that effectively isolates the corrosive environment of high salt spray and high humidity on the seabed, preventing the steel wire from rusting and reducing its mechanical strength, and ensuring the structural stability of the armor layer 200 during long-term service. For example, the outer diameter of the galvanized low-carbon steel wire is 6mm, which meets the requirements for tensile and compressive strength during the laying and operation of submarine cables, without increasing the overall weight and manufacturing cost of the armor layer 200 due to excessively large wire diameter, thus adapting to the lightweight design requirements of submarine cables.

[0033] The composite wire's metal core 221 is made of low-carbon steel, maintaining the same material properties as the ferromagnetic metal wire 210. This ensures uniform and stable mechanical properties of the armor layer 200, avoiding stress concentration issues caused by material differences. For example, the armor insulation layer 222 is 0.5mm thick and made of polyurethane, possessing excellent insulation, corrosion resistance, and wear resistance. On one hand, it reliably blocks the current path between the composite wire's metal core 221 and adjacent ferromagnetic metal wires 210, eliminating induced current loops within the armor layer 200 at the source and minimizing eddy current losses. On the other hand, it resists wear from seabed sediment, reefs, etc., extending the composite wire's service life. For example, the composite wire's outer diameter is 5mm, creating a reasonable match with the outer diameter of the ferromagnetic metal wire 210. When arranged alternately, they fit tightly together to form a continuous covering structure, preventing gaps in the armor layer 200 and further enhancing the protection of the cable core structure 100.

[0034] In other words, the combination of galvanized low-carbon steel wire and low-carbon steel core, along with reasonable outer diameter parameters, ensures that the armor layer 200 possesses excellent tensile, compressive, and corrosion resistance, enabling it to adapt to complex laying and operating conditions on the seabed and significantly extending the service life of the submarine cable. The high insulation properties of the polyurethane insulation layer ensure reliable isolation between the composite wire metal core 221 and the ferromagnetic metal wire 210, completely blocking the formation of induced current. Compared to the traditional method of inserting insulation components, the loss suppression effect is more stable and durable. The selected galvanized low-carbon steel wire, low-carbon steel core, and polyurethane materials are all mature industrial materials, with controllable procurement and processing costs. Furthermore, the reasonable outer diameter parameters avoid material waste, effectively controlling the overall manufacturing cost of the submarine cable while ensuring various performance characteristics. The matching outer diameter design of the ferromagnetic metal wire 210 and the composite wire ensures that the armor layer 200, formed by their alternating arrangement, has a compact structure and uniform stress distribution. This fully encloses the cable core structure 100 without causing cable core displacement due to a loose structure, ensuring the overall operational stability of the submarine cable.

[0035] In one embodiment of the present invention, such as Figure 1As shown, the cable core structure 100 includes: a conductive conductor 110 for transmitting power; a first water-blocking structure 120 covering the outside of the conductive conductor 110; an inner shielding layer 130 covering the outside of the first water-blocking structure 120; a main insulation layer 140 covering the outside of the inner shielding layer 130; an outer shielding layer 150 covering the outside of the main insulation layer 140; a second water-blocking structure 160 covering the outside of the outer shielding layer 150; a metal sheath 170 covering the outside of the second water-blocking structure 160; and a semi-conductive sheath 180 covering the outside of the metal sheath 170.

[0036] The cable core structure 100 adopts a layered and nested tightly wrapped design. From the inside out, it is arranged with a conductive conductor 110, a first water-blocking structure 120, an inner shielding layer 130, a main insulation layer 140, an outer shielding layer 150, a second water-blocking structure 160, and a metal sheath 170. The layers are tightly fitted together to form a complete and stable cable core transmission and protection system.

[0037] For example, the conductive conductor 110 is a water-blocking copper conductor. Copper has excellent conductivity, which can ensure low-loss transmission of electricity during long-distance transmission across water areas and meet the high-capacity power transmission needs of scenarios such as interconnection between the mainland and islands and grid connection of offshore wind power. The interior of the water-blocking copper conductor is filled with water-blocking material, which can quickly block the water penetration path when the conductor is partially damaged, and prevent water from spreading along the gaps in the conductor.

[0038] The first water-blocking structure 120 is a conductor water-blocking strip. This conductor water-blocking strip is tightly wrapped around the outside of the water-blocking copper conductor. Its material has a high water absorption rate and a high expansion rate. When it comes into contact with water, it can quickly expand to form a dense water-blocking barrier. Together with the internal water-blocking structure of the water-blocking copper conductor, it forms a double protection, preventing water from entering the conductor from the outside and avoiding oxidation and corrosion of the conductor due to moisture. This ensures the long-term stability of the conductivity of the conductive conductor 110.

[0039] The inner shielding layer 130 covers the outside of the conductor water-blocking strip. Its core function is to uniformly distribute the electric field on the surface of the water-blocking copper conductor, fill the microscopic protrusion defects on the conductor surface, and prevent the main insulation layer 140 from being locally broken down due to electric field concentration. At the same time, it can effectively suppress the corona discharge phenomenon on the conductor surface, reduce local power loss, and improve the operational safety and energy efficiency of the submarine cable.

[0040] The main insulation layer 140 covers the outer side of the inner shielding layer 130 and is the core structure for realizing the electrical insulation of the submarine cable. It must have excellent insulation performance, electrical strength and weather resistance, and be able to effectively block the current path between the inside and outside of the cable core to prevent electrical faults such as leakage and short circuit, and adapt to the harsh working conditions of submarine high-voltage power transmission.

[0041] The outer shielding layer 150 covers the outside of the main insulation layer 140 and forms a shielding system in cooperation with the inner shielding layer 130. On the one hand, it can uniformly distribute the electric field on the outside of the main insulation layer 140 and eliminate the problem of electric field distortion on the surface of the insulation layer. On the other hand, it can timely draw out the induced charge generated on the surface of the main insulation layer 140, further ensuring the uniformity of the electric field distribution and preventing the main insulation layer 140 from aging or being damaged due to long-term accumulation of charge.

[0042] The second water-blocking structure 160 is a semi-conductive water-blocking tape. This semi-conductive water-blocking tape is tightly wrapped around the outside of the outer shielding layer 150, and has both semi-conductive and water-blocking properties. Its semi-conductive properties can ensure that the charge conduction effect of the outer shielding layer 150 is not affected, while its water-blocking properties can prevent moisture from penetrating from the outside of the cable core to the inside. The water-blocking copper conductor, the conductor water-blocking tape, and the semi-conductive water-blocking tape work together to achieve water blocking from the conductor core to the outer layer of the cable core. Even if the outer sheath of the submarine cable is partially damaged, moisture cannot penetrate the multi-layer water-blocking barrier to invade the conductor, which greatly improves the moisture-proof and waterproof capabilities of the cable core.

[0043] The metal sheath 170 is specifically an alloy lead sheath, which tightly wraps around the outside of the semi-conductive resistive water tape. The lead alloy material has excellent ductility and sealing properties, which can provide solid mechanical protection for the cable core structure 100, resisting external forces such as compression, abrasion and impact during the laying process on the seabed, and further block the intrusion of water and corrosive media, thus enhancing the protective effect of the cable core. At the same time, the alloy lead sheath has good conductivity and can serve as a key component of the conductive path. Together with the subsequent filler layer 300, wrapping tape 400 and other structures, it can achieve full-route grounding and ensure the operational reliability of the submarine cable.

[0044] Through the above structural design, firstly, the synergistic design of the water-blocking copper conductor, the conductor water-blocking strip, and the semi-conducting water-blocking strip constructs a multi-layered water-blocking barrier from the conductor core to the outer layer of the cable core, achieving full-route water blocking. This effectively prevents moisture penetration, avoids conductor oxidation and insulation dampness, and significantly improves the weather resistance and service life of the submarine cable in the high humidity environment of the seabed. Secondly, the synergistic effect of the inner shielding layer 130 and the outer shielding layer 150 can uniformly distribute the electric field and suppress corona discharge. Combined with the high insulation performance of the main insulation layer 140, it can effectively avoid insulation breakdown caused by electric field concentration, reduce the incidence of electrical faults, and meet the operating requirements of high-voltage cross-water power transmission. Furthermore, the alloy lead sheath provides the cable core with a dual effect of mechanical protection and sealing protection, resisting damage from external forces on the seabed and preventing the intrusion of corrosive media, further improving the stability of the cable core structure 100. In addition, the alloy lead sheath has good conductivity and can serve as the core component of the conductive path, providing a foundation for the full-route grounding of subsequent structures such as the filler layer 300 and the wrapping tape 400, thus ensuring the electrical safety and operational stability of the submarine cable.

[0045] In one embodiment of the present invention, the number of cable core structures 100 is multiple.

[0046] In one embodiment of the present invention, the submarine cable further includes: a filling layer 300 disposed between each cable core structure 100; a wrapping tape 400 wrapped around the outside of the filling layer 300; an inner lining layer 500 covering the outside of the wrapping tape 400; and an outer sheath 700 covering the outside of the armor layer 200.

[0047] Furthermore, in one embodiment of the present invention, the filler layer 300 is a polyacetylene filler layer; the wrapping tape 400 is a semi-conductive non-woven fabric wrapping tape; the inner lining layer 500 is a semi-conductive polyethylene inner lining layer; the filler layer 300, the wrapping tape 400 and the inner lining layer 500 work together to form a continuous conductive path, one end of the conductive path is electrically connected to the metal sheath 170 and the other end is electrically connected to the armor layer 200, thereby realizing full-path grounding of the metal sheath 170 and the armor layer 200.

[0048] For example, such as Figure 1 As shown, the number of cable core structures 100 is set to 3, and the 3 cable core structures 100 are evenly distributed in an equilateral triangle. This arrangement can make the overall structure of the submarine cable bear the force evenly, while maximizing the use of the gap space between the cable cores and improving the structural compactness.

[0049] Based on the distributed design of the three cable core structures 100, the submarine cable also includes a filler layer 300, a wrapping tape 400, and an inner lining layer 500. The filler layer 300 is located in the gaps between the three cable core structures 100 and is specifically made of polyacetylene. Polyacetylene material has excellent electrical and thermal conductivity. During the filling process, a compaction filling process is used to ensure that the gaps between each cable core structure 100 are completely filled, making the three cable core structures 100 form a stable whole and preventing structural damage due to cable core displacement during laying or operation.

[0050] The wrapping tape 400 is tightly wrapped around the outside of the filler layer 300 and the three cable core structures 100. Specifically, a semi-conductive non-woven fabric wrapping tape is selected. The semi-conductive non-woven fabric is soft and has a certain tensile strength. When wrapping, an overlapping wrapping method is adopted, and the overlap rate is controlled at 20%-30%. This can further fix the relative position of the cable core structure 100 and the filler layer 300, prevent the filler layer 300 from falling off or shifting, and its semi-conductive properties can ensure the smooth conduction of charge and avoid the accumulation of charge.

[0051] The inner lining layer 500 tightly wraps around the outside of the wrapping tape 400, specifically using a semi-conductive polyethylene inner lining layer. Semi-conductive polyethylene has excellent insulation, wear resistance, and processing and molding properties. It is formed by extrusion coating process, which can tightly fit with the wrapping tape 400 to form a smooth inner surface, providing a flat base for the subsequent armor layer 200 coating. At the same time, it can effectively isolate the armor layer 200 from the internal cable core structure 100, avoiding mechanical damage to the cable core caused by the armor layer 200.

[0052] The polyacetylene filler layer, the semi-conductive nonwoven fabric wrapping tape, and the semi-conductive polyethylene inner liner layer work together to form a continuous conductive path. Specifically, the polyacetylene filler layer is in close contact with the metal sheath 170 (alloy lead sheath) of each cable core structure 100 to achieve electrical connection. The semi-conductive nonwoven fabric wrapping tape adheres to the polyacetylene filler layer to conduct charge. The semi-conductive polyethylene inner liner layer is in contact with the semi-conductive nonwoven fabric wrapping tape and the outer armor layer 200 respectively. Ultimately, one end of the conductive path is stably electrically connected to the metal sheath 170 of each cable core structure 100, and the other end is reliably electrically connected to the armor layer 200, thereby achieving full-path grounding of the metal sheath 170 and the armor layer 200. This full-path grounding design can promptly conduct the induced charge generated during the operation of the submarine cable to the ground, avoiding charge accumulation that leads to electric field distortion. At the same time, it can quickly discharge fault current, ensuring the operational safety of the submarine cable. An outer sheath 700 is provided on the outside of the armor layer 200, for example, the outer sheath 700 is a polypropylene outer sheath 700.

[0053] In this embodiment, the uniform distribution of the three cable core structures 100 in an equilateral triangle pattern, along with the compacted filling design of the polyacetylene filling layer, makes the internal structure of the submarine cable compact and stable, effectively preventing cable core displacement. Combined with the overlapping wrapping and fixing of the semi-conductive non-woven fabric tape, this further enhances the integrity and impact resistance of the overall structure. The excellent electrical and thermal conductivity of the polyacetylene filling layer not only provides a core conductive carrier for end-to-end grounding but also rapidly conducts the heat generated during the operation of the submarine cable to the outside. Combined with the heat diffusion effect of the semi-conductive tape 400 and the inner lining layer 500, this improves the heat dissipation efficiency of the submarine cable and prevents the accumulation of localized high temperatures. The semi-conductive / conductive materials of the filling layer 300, tape 400, and inner lining layer 500 work together to form a continuous and uninterrupted conductive path, precisely achieving end-to-end grounding of the metal sheath 170 and armor layer 200. This effectively dissipates induced charges and fault currents, avoids the risk of electric field distortion and insulation breakdown, and improves the electrical operational safety of the submarine cable. The semi-conductive polyethylene material of the inner lining layer 500 has good wear resistance and isolation properties, which can effectively protect the internal cable core structure 100 and prevent the mechanical friction of the outer armor layer 200 from damaging the cable core. At the same time, the synergistic fixing effect of the wrapping tape 400 and the filling layer 300 further enhances the overall mechanical damage resistance of the submarine cable, making it suitable for complex laying and operation conditions on the seabed.

[0054] In one embodiment of the present invention, the submarine cable further includes at least one cooling pipe 600, each cooling pipe 600 being synchronously twisted with the cable core structure 100 into the filling layer 300.

[0055] Furthermore, in one embodiment of the present invention, the submarine cable further includes a cooling circulation module, which is connected to each cooling pipe 600 and is used to provide circulating coolant to the cooling pipe 600 when the actual temperature of the submarine cable exceeds a preset temperature threshold.

[0056] Specifically, such as Figure 1 As shown, based on the submarine cable that includes three core structures 100, a filling layer 300, a wrapping tape 400 and an inner lining layer 500, a cooling pipe 600 and a cooling circulation module are added to form a submarine cable structure with active heat dissipation function, so as to further improve the high temperature resistance and transmission capacity of the submarine cable.

[0057] The cooling pipes 600 can be configured as three, meaning one cooling pipe 600 is placed between every two adjacent cable core structures 100. Each cooling pipe 600 is evenly spaced from each cable core structure 100. The three cooling pipes 600 and the three cable core structures 100 are simultaneously twisted into the inner region of the filler layer 300. The cooling pipes 600 are made of stainless steel, which possesses excellent corrosion resistance, mechanical strength, and thermal conductivity. This allows them to withstand the harsh environment of high salt spray and high pressure on the seabed, preventing rust or damage during long-term service, and also enabling rapid heat conduction within the submarine cable. In the twisting process, the cooling pipes 600 and the cable core structures 100 are twisted synchronously in the same direction and with the same pitch, ensuring a tight fit between the cooling pipes 600, the cable core structures 100, and the filler layer 300 after twisting. This prevents displacement or loosening of the cooling pipes 600 during bending and laying or operation of the submarine cable, ensuring stable heat dissipation.

[0058] The cooling circulation module, serving as the control and power core of the cooling system, includes a circulation pump, temperature sensors, a controller, and a storage tank. Each component is connected to both ends of the cooling pipe 600 via pipelines, forming a closed circulation loop. Temperature sensors are evenly distributed on the outside of the cable core structure 100 and within the filling layer 300 of the submarine cable to collect the actual operating temperature of the cable in real time and transmit the temperature data to the controller. The controller has a built-in preset temperature threshold (which can be set according to the rated transmission capacity of the submarine cable and the temperature tolerance of the insulation material). It determines whether to activate the cooling function by comparing the real-time temperature with the preset threshold. The circulating coolant stored in the storage tank is deionized water, which has excellent thermal conductivity and insulation properties and is cost-effective, and will not cause a short circuit risk to the internal conductive structure of the submarine cable. When the temperature sensor detects that the actual temperature of the submarine cable exceeds the preset threshold, the controller immediately issues a command to start the circulation pump. The circulation pump injects low-temperature deionized water from the storage tank into the cooling pipe 600. As the low-temperature coolant flows within the cooling pipe 600, it quickly absorbs the heat generated inside the submarine cable (such as the cable core structure 100 and the filling layer 300). The heated coolant then returns to the storage tank through the return pipe, completing one heat dissipation cycle. If the temperature subsequently drops below the preset threshold, the controller commands the circulation pump to stop running, realizing intelligent start-stop control of the cooling system.

[0059] Therefore, through the coordinated design of the cooling pipe 600 and the cooling circulation module, the temperature of the submarine cable can be monitored in real time and heat dissipation can be intelligently activated to quickly remove the heat accumulated during the operation of the submarine cable. This effectively solves the problem of high temperature accumulation caused by armor loss and transmission loss in traditional submarine cables, allowing the submarine cable to operate within a safe temperature range for a long time. This significantly improves the rated transmission capacity of the submarine cable and adapts to the needs of large-capacity cross-water power transmission. The synchronous twisting design of the cooling pipe 600 and the cable core structure 100 ensures that the cooling pipe 600 is in close contact with the heat-generating components, improving heat conduction efficiency. The corrosion resistance, pressure resistance, and closed-loop design of the stainless steel cooling pipe 600 prevent leakage, corrosion, and other failures in the cooling system, ensuring the long-term stable operation of the heat dissipation function. The intelligent control function of the cooling circulation module can achieve temperature adaptive adjustment without manual intervention, reducing operation and maintenance costs. Effective temperature control can reduce the aging damage of high temperature to the submarine cable insulation material, delay the performance degradation of key structures such as the main insulation layer 140 and the shielding layer, and avoid problems such as increased conductor resistance and increased loss caused by high temperature, further improving the operational safety and service life of the submarine cable.

[0060] A second aspect of the present invention provides an offshore wind power system including the submarine cable as described above.

[0061] Furthermore, the offshore wind power system provided by this invention, since it includes the submarine cable as described above, also possesses the advantages described above.

[0062] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention 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 of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A submarine cable, characterized in that, include: Cable core structure (100); The armor layer (200) covers the outside of the cable core structure (100). The armor layer (200) includes ferromagnetic metal wires (210) and composite wires. The ferromagnetic metal wires (210) and the composite wires are arranged alternately to form a continuous covering structure. The composite wire includes a metal core (221) and an armor insulation layer (222). The armor insulation layer (222) covers the outside of the metal core (221) and is used to block the formation of induced current in the armor layer (200).

2. The submarine cable according to claim 1, characterized in that, The cable core structure (100) includes: A conductive conductor (110) is used to transmit electricity; A first water-blocking structure (120) is formed, which covers the outside of the conductive conductor (110); An inner shielding layer (130) is provided, which covers the outside of the first water-blocking structure (120); A main insulating layer (140) covers the outside of the inner shielding layer (130); An outer shielding layer (150) covers the outside of the main insulating layer (140); The second water-blocking structure (160) covers the outside of the outer shielding layer (150); A metal sheath (170) covers the outside of the second water-blocking structure (160); A semi-conductive sheath (180) covers the outside of the metal sheath (170).

3. The submarine cable according to claim 2, characterized in that, The number of the cable core structures (100) is multiple.

4. The submarine cable according to claim 3, characterized in that, The submarine cable also includes: A filling layer (300) is disposed between each of the cable core structures (100); A strap (400) is wrapped around the outside of the filler layer (300); An inner lining (500) covers the outside of the strap (400); An outer sheath (700) covers the outside of the armor layer (200).

5. The submarine cable according to claim 4, characterized in that, The filler layer (300) is a polyacetylene filler layer; The strap (400) is a semi-conductive non-woven fabric strap; The inner liner (500) is a semi-conductive polyethylene inner liner; The filling layer (300), the wrapping tape (400), and the inner lining layer (500) work together to form a continuous conductive path. One end of the conductive path is electrically connected to the metal sheath (170), and the other end is electrically connected to the armor layer (200), thereby achieving full-path grounding of the metal sheath (170) and the armor layer (200).

6. The submarine cable according to claim 4, characterized in that, The submarine cable also includes: At least one cooling pipe (600) is provided, and each cooling pipe (600) is synchronously twisted into the filling layer (300) along with the cable core structure (100).

7. The submarine cable according to claim 6, characterized in that, The submarine cable also includes: A cooling circulation module is connected to each of the cooling pipes (600) and is used to provide circulating coolant to the cooling pipes (600) when the actual temperature of the submarine cable exceeds a preset temperature threshold.

8. The submarine cable according to claim 5, characterized in that, The conductive conductor (110) is a water-blocking copper conductor; the first water-blocking structure (120) is a conductor water-blocking strip; the second water-blocking structure (160) is a semi-conductive water-blocking strip; the metal sheath (170) is an alloy lead sheath; The water-blocking copper conductor, the conductor water-blocking tape, and the semi-conductive water-blocking tape work together to achieve full-route water blocking. The alloy lead sleeve, the filling layer (300), the wrapping tape (400), and the inner lining layer (500) form the conductive path.

9. The submarine cable according to any one of claims 1 to 8, characterized in that, The ferromagnetic metal wire (210) is a galvanized low-carbon steel wire with an outer diameter of 5-7 mm; the metal core (221) is a low-carbon steel core; the armored insulation layer (222) is a polyurethane layer with an outer diameter of 4-6 mm.

10. An offshore wind power system, characterized in that, include: The submarine cable as described in any one of claims 1 to 9.

Images