An ultra-high voltage dc submarine cable with an armored composite sensor unit
By integrating the optical cable into the steel wire armor layer through the armored composite sensing unit design, the problem of large outer diameter and heavy weight of high voltage DC submarine cables is solved, achieving cost savings and improved stability.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-06-09
- Publication Date
- 2026-07-03
AI Technical Summary
Existing high-voltage DC submarine cables have large outer diameters and heavy weights, making them difficult to manufacture and lay, resulting in high material costs and construction energy consumption. Furthermore, their traditional structures are not conducive to long-term stability.
The traditional fiber optic cable filling and wrapping layers of submarine cables are eliminated. Instead, an armored composite sensing unit design is adopted, which integrates the fiber optic cable into the steel wire armor layer to form an armored composite sensing unit. This reduces the outer diameter and weight of the submarine cable and improves production efficiency and stability.
This effectively reduces the outer diameter and weight of submarine cables, lowers manufacturing and laying costs, improves production efficiency, reduces process difficulty, and ensures the long-term stability of ultra-high voltage direct current transmission.
Smart Images
Figure CN224457678U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the field of submarine power transmission technology, specifically relating to an ultra-high voltage DC submarine cable with an armored composite sensing unit. Background Technology
[0002] The statements herein provide only background information related to this invention and do not necessarily constitute prior art.
[0003] In existing technologies, the structure of high-voltage direct current submarine cables generally includes a water-blocking conductor, a conductor wrapping layer, a conductor shielding layer, an insulation layer, an insulation shielding layer, a semi-conductive water-blocking wrapping layer, a metal sheath layer, a semi-conductive PE sheath layer, a wrapping layer, an optical fiber / cable protective layer, an inner lining layer, an armor layer, and an outer sheath layer, etc. Among these, the optical fiber / cable used to achieve high-speed, high-capacity, long-distance data communication across oceans is usually built into its protective layer.
[0004] High-voltage direct current (HVDC) submarine cables possess excellent electrical, corrosion-resistant, and mechanical properties. Their design typically requires a multi-layered composite structure, resulting in a larger outer diameter and significantly increasing the difficulty of manufacturing and laying compared to HVDC terrestrial cables. Furthermore, the increased outer diameter of HVDC submarine cables necessitates a greater amount of steel wire used in the armor layer, leading to a substantial increase in the weight per unit length of the submarine cable. This creates a dual constraint on development, balancing material costs with energy consumption in offshore construction. Utility Model Content
[0005] The purpose of this invention is to overcome the shortcomings of the existing technology and provide an ultra-high voltage DC submarine cable with an armored composite sensing unit. This invention eliminates the optical cable filling protective layer and wrapping layer structure of traditional submarine cables. By integrating the armor layer and optical cable into a compact structure design to form an armored composite sensing unit, the outer diameter of the submarine cable is effectively reduced, and the weight of the submarine cable per unit length is lighter. This effectively saves manufacturing, laying, transportation and installation costs and ensures the long-term operational stability of ultra-high voltage DC power transmission.
[0006] To achieve the above objectives, this utility model is implemented through the following technical solution:
[0007] The present invention provides an ultra-high voltage DC submarine cable with an armored composite sensing unit, comprising: a water-blocking conductor, and an outer sheath consisting of a conductor semi-conductive wrapping layer, a shielding and insulation layer, a semi-conductive buffer water-blocking tape, a lead alloy sheath layer, a semi-conductive PE sheath layer, an inner lining layer, an armored composite sensing unit, and an outer sheath layer; wherein, the armored composite sensing unit is composed of optical cables symmetrically distributed within a steel wire armor layer, and the outer diameter of the optical cables is smaller than the nominal diameter of the steel wires in the steel wire armor layer.
[0008] In at least one embodiment, the water-blocking conductor is a multi-layer conductor structure with a circular copper rod at its center, and an outer conductor structure formed by tightly pressing irregularly shaped copper monofilaments around the circular copper rod; depending on different conductor cross-sections, the maximum number of irregularly shaped copper monofilaments in each outer conductor layer outside the circular copper rod is X. n =6×n, where n is the current number of outer conductor layers.
[0009] In at least one embodiment, a water-blocking strip is filled between each layer of the conductor structure of the water-blocking conductor.
[0010] In at least one embodiment, the gap between the water-blocking conductor and the conductor semiconducting wrapping layer is filled with water-blocking powder.
[0011] In at least one embodiment, the conductor semi-conductive wrapping layer is bound with a semi-conductive nylon tape with a moisture content of no more than 1.5%; or, the conductor semi-conductive wrapping layer is bound with a semi-conductive terylene tape with a moisture content of no more than 1.5%.
[0012] In at least one embodiment, the shielding and insulating layer comprises, from the inside out, a conductor shielding layer, an insulating layer, and an insulating shielding layer; the conductor shielding layer, the insulating layer, and the insulating shielding layer are integrally formed using a three-layer co-extrusion process.
[0013] In at least one embodiment, the outer layer of the lead alloy sheath is coated with an asphalt anti-corrosion layer.
[0014] In at least one embodiment, the semi-conductive PE sheath layer is extruded onto the outside of the asphalt anti-corrosion layer.
[0015] In at least one embodiment, the inner lining is a polypropylene submarine cable tying wrapping structure.
[0016] In at least one embodiment, the outer sheath is a polypropylene fiber rope wrapped structure; the gap between the outer sheath and the armored composite sensing unit is filled with asphalt; and the outer side of the outer sheath is coated with anti-corrosion asphalt.
[0017] The beneficial effects of the above-described technical solution of this utility model are as follows:
[0018] This utility model discloses an ultra-high voltage direct current submarine cable with an armored composite sensing unit. It eliminates the traditional optical fiber filling and wrapping layer structure of submarine cables. By integrating the armor layer and optical fiber into a compact structure to form an armored composite sensing unit, the outer diameter of the submarine cable is effectively reduced, resulting in a lighter cable weight per unit length. This significantly saves on manufacturing, laying, transportation, and installation costs, and improves production efficiency. Furthermore, with the further reduction in the outer diameter, the amount of steel wire used in the armor layer is reduced, greatly simplifying the manufacturing process and facilitating cable laying and installation. Simultaneously, the compact structure design of the "armored composite sensing unit" ensures the long-term stability of ultra-high voltage direct current transmission, achieving high-efficiency cost reduction and operational efficiency improvement in direct current transmission technology. Attached Figure Description
[0019] The accompanying drawings, which form part of this specification, are used to provide a further understanding of this utility model. The illustrative embodiments of this utility model and their descriptions are used to explain this utility model and do not constitute an improper limitation of this utility model.
[0020] Figure 1 This is a schematic diagram of the cross-sectional structure of an armored composite sensing unit for an ultra-high voltage DC submarine cable disclosed in Embodiment 1 of this utility model.
[0021] In the diagram: 1. Water-blocking conductor; 2. Semi-conductive conductor wrapping layer; 3. Conductor shielding layer; 4. Insulation layer; 5. Insulation shielding layer; 6. Semi-conductive buffer water-blocking tape; 7. Lead alloy sheath layer; 8. Semi-conductive PE sheath layer; 9. Inner lining layer; 10. Optical cable; 11. Steel wire armor layer; 12. Outer sheath layer.
[0022] The distances or dimensions between parts have been exaggerated to show their positions; the diagram is for illustrative purposes only. Detailed Implementation
[0023] It should be noted that the following detailed description is illustrative and intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.
[0024] As described in the background section, the purpose of this invention is to overcome the shortcomings of the existing technology and provide an ultra-high voltage direct current submarine cable with an armored composite sensing unit. This eliminates the traditional optical fiber filling and wrapping layer structure of submarine cables. By integrating the armor layer and optical fiber into a compact structure to form an armored composite sensing unit, the outer diameter of the submarine cable is effectively reduced, resulting in a lighter cable weight per unit length. This effectively saves on manufacturing, laying, transportation, and installation costs, and improves production efficiency. Furthermore, as the outer diameter of the submarine cable is further reduced, the amount of steel wire used in the armor layer is decreased, significantly reducing manufacturing difficulty and facilitating cable laying and installation. Simultaneously, the compact structure design of the "armored composite sensing unit" ensures the long-term stability of ultra-high voltage direct current transmission, achieving high-efficiency cost reduction and operational efficiency improvement in direct current transmission technology.
[0025] Example 1
[0026] In a typical embodiment of this utility model, such as Figure 1 As shown, this embodiment discloses an ultra-high voltage DC submarine cable with an armored composite sensing unit, comprising: a water-blocking conductor 1, and outside the water-blocking conductor 1, a conductor semi-conductive wrapping layer 2, a shielding and insulation layer, a semi-conductive buffer water-blocking tape 6, a lead alloy sheath layer 7, a semi-conductive PE sheath layer 8, an inner liner layer 9, an armored composite sensing unit, and an outer sheath layer 12. The armored composite sensing unit consists of optical cables 10 symmetrically distributed around the water-blocking conductor 1, embedded within a steel wire armor layer 11. The outer diameter of the optical cables 10 is smaller than the nominal diameter of the steel wires in the steel wire armor layer 11. By rearranging the positions of the distributed independent sensing optical cables and integrating them symmetrically within the steel wire armor layer 11, an armored composite sensing unit is formed. This eliminates the need for the wrapping layer and fiber / optical cable protective layer found in traditional ultra-high voltage submarine cable structures, significantly reducing the outer diameter of the submarine cable, resulting in a lighter weight per unit length and easier installation and laying. Moreover, as the outer diameter of the submarine cable decreases, the amount of steel wire used in the steel wire armor layer 11 also decreases, further saving on the manufacturing and equipment costs of ultra-high voltage DC submarine cables and reducing the difficulty of the process.
[0027] As an alternative implementation, the type of steel wire in the steel wire armor layer 11 of the armored composite sensing unit is selected according to the tension requirements of the submarine cable armor during laying. In this embodiment, galvanized steel wire is used, with a tensile strength of 1200-1800MPa. The galvanized layer on its surface is uniform, and its adhesion does not fall off after passing the standard winding test. The nominal diameter of the steel wire can be selected from 4mm to 8mm. Considering the tension requirements of the submarine cable during laying and the difficulty of the manufacturing process, a nominal diameter of 6mm is preferred in this embodiment. The outer diameter of the optical cable 10 built into the steel wire armor layer 11 is smaller than the nominal diameter of the steel wire in the steel wire armor layer 11. The outer diameter of the optical cable 10 is usually set to be in the range of 4.5mm-5.5mm. Considering the current submarine cable and optical cable manufacturing processes, the outer diameter of the optical cable is preferably 4.8mm in this embodiment. The optical cable 10 is symmetrically distributed along the armor layer with the water-blocking conductor 1 as the center. The test data of the two optical cables with symmetrical structure can be mutually calibrated, which can effectively reduce the problem of local abnormalities caused by optical cable bending that cannot be detected.
[0028] As an alternative implementation, the water-blocking conductor 1 is a multi-layered conductor structure with a circular copper rod at its center. An outer conductor structure is formed by tightly pressing irregularly shaped copper monofilaments around the circular copper rod. Furthermore, depending on the conductor cross-section, the maximum number of irregularly shaped copper monofilaments in each outer conductor layer outside the circular copper rod is X. n = 6 × n, where n is the current number of outer conductor layers. For example... Figure 1 As shown, in this embodiment, the center of the water-blocking conductor 1 is a circular copper rod. Outside the circular copper rod, depending on the cross-section, the outer conductors are formed using a layered compaction process to create the conductor structure. To make the submarine cable more suitable for the seabed environment, water-blocking tape is filled between each layer of the water-blocking conductor 1 to enhance its water-blocking performance. Furthermore, the gap between the water-blocking conductor 1 and the conductor semi-conductive wrapping layer 2 is filled with water-blocking powder to further enhance the water-blocking performance of the submarine cable.
[0029] As an alternative implementation, the conductor semi-conductive wrapping layer 2 can be formed by bundling semi-conductive nylon tape or semi-conductive terylene tape with a moisture content of ≤1.5% to prevent burrs or defects of the water-blocking conductor 1 from directly contacting the conductor shielding layer 3 in the shielding and insulation layer and causing electric field distortion, thus playing a protective and uniform electric field role.
[0030] As an alternative implementation, the shielding and insulation layers, from the inside out, include a conductor shielding layer 3, an insulation layer 4, and an insulation shielding layer 5. The conductor shielding layer 3, insulation layer 4, and insulation shielding layer 5 are integrally formed using a three-layer co-extrusion process. Compared to assembling layer by layer after extrusion, this embodiment uses a three-layer co-extrusion integral forming method, which can effectively eliminate interlayer interface defects. Simultaneously, the integrated forming process, combined with an online continuous degassing process, effectively removes volatile impurities such as methane and cumyl alcohol, further improving the breakdown resistance of the shielding and insulation layers, preventing partial discharge caused by volatile impurities, and avoiding insulation breakdown or even cable combustion.
[0031] As an alternative implementation, the semi-conductive buffer water-blocking tape 6 is made of non-woven fabric, semi-conductive material and highly absorbent material. Its surface has uniform fiber distribution and no wrinkles. It has good compatibility with lead alloy sheath layer 7 and other adjacent materials. It can compensate for thermal expansion during submarine cable operation, avoid water treeing, and prevent burns and impacts to the shielding material during lead extrusion.
[0032] As an alternative implementation, the lead alloy sheath layer 7 is produced by continuous extrusion, which provides radial water blocking and seawater corrosion resistance, and shares the short-circuit current. An asphalt anti-corrosion layer is poured on the outer layer of the lead alloy sheath layer 7 using a melt casting process. The pouring thickness is usually 0.5 mm, which enhances the anti-corrosion performance of the submarine cable in seawater.
[0033] As an alternative implementation, a semi-conductive PE sheath is extruded on the outside of the asphalt anti-corrosion layer of the lead alloy sheath layer 7, which can play a role in mechanical protection and further enhance the safety of the submarine cable.
[0034] As an alternative implementation, the inner liner 9 is made of polypropylene (PP) cable ties, which acts as a buffer to reduce the pressure of seawater on the cable. A steel wire armor layer 11 is wrapped around the outside of the inner liner 9, and anti-corrosion asphalt is applied between the inner liner 9 and the steel wire armor layer 11 to further enhance the anti-corrosion performance of the cable.
[0035] As an alternative implementation, the outer sheath 12 is made of polypropylene (PP) fiber rope or fiber tape wrapped around the cable to prevent damage during transportation and storage. Anti-corrosion asphalt is used to fill the gap between the fiber tape and the steel wire armor layer 11 to slow down the corrosion rate in seawater. At the same time, the outer sheath 12 is also coated with anti-corrosion asphalt, with a coating thickness of 0.5 mm.
[0036] It should be noted that the asphalt coating processes for the inner lining layer 9, the steel wire armor layer 11, and the outer lining layer 12 are on the same production line and are applied sequentially according to the order in which they pass through. That is, during the production process, the coating production lines for the inner lining layer 9, the steel wire armor layer 11, and the outer lining layer 12 are combined into one line, and the inner lining layer 9 is coated first, followed by the steel wire armor layer 11, and finally the outer lining layer 12, according to the order in which they pass through.
[0037] This invention relates to an armored composite sensing unit for ultra-high voltage direct current submarine cables. Compared with current ultra-high voltage submarine cable structures, it eliminates the need for wrapping layers and fiber / optical cable 10 protective layers, fundamentally saving on manufacturing and equipment costs and reducing process complexity. Through the compact structural design of the "armored composite sensing unit," the outer diameter of the submarine cable is significantly reduced, resulting in a lighter weight per unit length, easier installation and laying, and ensuring the long-term stability and safety of ultra-high voltage direct current transmission.
[0038] The above are merely preferred embodiments of this utility model and are not intended to limit the scope of this utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of this utility model should be included within the protection scope of this utility model.
Claims
1. An ultra-high voltage direct current submarine cable of the armored composite sensor unit type, characterized in that, include: A water-blocking conductor, wherein the water-blocking conductor is sequentially provided with a conductor semi-conductive wrapping layer, a shielding and insulation layer, a semi-conductive buffer water-blocking tape, a lead alloy sheath layer, a semi-conductive PE sheath layer, an inner lining layer, an armored composite sensing unit, and an outer sheath layer; wherein the armored composite sensing unit is composed of optical cables symmetrically distributed within a steel wire armor layer, and the outer diameter of the optical cables is smaller than the nominal diameter of the steel wires in the steel wire armor layer.
2. An ultra-high voltage DC submarine cable with an armored composite sensor unit according to claim 1, characterized in that, The water-blocking conductor is a multi-layered conductor structure with a central circular copper rod. An outer conductor structure is formed by tightly pressing irregularly shaped copper monofilaments around the circular copper rod. Depending on the conductor cross-section, the maximum number of irregularly shaped copper monofilaments in each outer conductor layer outside the circular copper rod is X. n =6×n, where n is the current number of outer conductor layers.
3. A UHV DC submarine cable with an armored composite sensor unit according to claim 2, characterized in that, The water-blocking conductor has a water-blocking strip filling the space between each layer of conductor structure.
4. The ultra-high voltage DC submarine cable with an armored composite sensing unit as described in claim 1, characterized in that, The gap between the water-blocking conductor and the conductor semi-conductive wrapping layer is filled with water-blocking powder.
5. An ultra-high voltage DC submarine cable with an armored composite sensor unit according to claim 1, characterized in that, The conductor semi-conductive wrapping layer is bound with semi-conductive nylon tape with a moisture content of no more than 1.5%; or, the conductor semi-conductive wrapping layer is bound with semi-conductive terylene tape with a moisture content of no more than 1.5%.
6. An ultra-high voltage DC submarine cable with an armored composite sensor unit according to claim 1, characterized in that, The shielding and insulation layers, from the inside out, consist of a conductor shielding layer, an insulation layer, and an insulating shielding layer; the conductor shielding layer, insulation layer, and insulating shielding layer are integrally formed using a three-layer co-extrusion process.
7. An ultra-high voltage DC submarine cable with an armored composite sensor unit according to claim 1, characterized in that, The outer layer of the lead alloy sheath is coated with an asphalt anti-corrosion layer.
8. An ultra-high voltage DC submarine cable with an armored composite sensor unit according to claim 7, characterized in that, The semi-conductive PE sheath layer is extruded on the outside of the asphalt anti-corrosion layer.
9. An ultra-high voltage DC submarine cable with an armored composite sensor unit according to claim 1, characterized in that, The inner lining is a polypropylene submarine cable tying wrapping structure.
10. An ultra-high voltage DC submarine cable with an armored composite sensor unit according to claim 1, characterized in that, The outer sheath is a polypropylene fiber rope wrapped structure; the gap between the outer sheath and the armored composite sensing unit is filled with asphalt; the outer side of the outer sheath is coated with anti-corrosion asphalt.