Submarine cable for 66kV and below

Abstract

The utility model relates to a 66kV and below section submarine cable, which comprises a central unit and an outer layer unit, and is characterized in that the central unit comprises a plurality of conductive cable cores, at least one conductive cable core and fillers; the conductive cable core comprises a water-blocking conductor, a conductor shielding layer, an insulating layer, an insulation shielding layer, a first longitudinal water-blocking layer, a metal shielding layer, a second longitudinal water-blocking layer, a radial water-blocking layer and a non-metal sheath layer which are sequentially sleeved from inside to outside, and the water-blocking conductor comprises enameled wire conductors stranded in a layered manner and salt water-resistant water-blocking tapes stranded on each layer of enameled wire conductor; the radial waterproof layer is a lead foil or a lead foil composite belt, the outer layer unit is sleeved on the outer side of the central unit, and the outer layer unit comprises a cabling mothproof layer, a lining layer, an armor layer and an outer coating layer which are sequentially sleeved from inside to outside. According to the submarine cable for 66kV and below, the product performance of the current-carrying capacity and the transmission capacity is obviously improved.

Description

Technical Field

[0001] This utility model relates to the field of cable production technology, and in particular to a submarine cable with a range of 66kV and below. Background Technology

[0002] Offshore wind power typically involves generating electricity from offshore wind turbines and transmitting it to offshore substations. From these substations, high-voltage (110kV and above) submarine cables connect the turbines to the onshore power grid. The number of wind turbines procured is usually in the dozens or hundreds, resulting in a considerable amount of submarine cable for interconnecting the turbines and connecting them to the substations – conservatively estimated at several hundred kilometers based on the scale of the wind farm. Currently, domestic offshore wind power submarine cables primarily use 35kV and 66kV voltage levels. Improving the current carrying capacity and transmission capacity of these cables, both in conventional and harsh environments for both offshore and onshore wind power, is a pressing technical challenge that needs to be addressed in this field. Utility Model Content

[0003] Therefore, this utility model provides a submarine cable for 66kV and below that improves the performance of current carrying capacity and transmission capacity.

[0004] To solve the above-mentioned technical problems, this utility model provides a submarine cable for 66kV and below, comprising:

[0005] The central unit comprises multiple cable cores, at least one optical fiber core, and filler. The multiple cable cores are evenly distributed around the central axis of the submarine cable, and an outer angle space is formed between adjacent cable cores away from the center of the submarine cable. Each cable core includes, from the inside out, a water-blocking conductor, a conductor shielding layer, an insulation layer, an insulation shielding layer, a first longitudinal water-blocking layer, a metal shielding layer, a second longitudinal water-blocking layer, a radial water-blocking layer, and a non-metallic sheath layer. The water-blocking conductor includes layered stranded enameled wire conductors and salt-resistant water-blocking tape stranded on each layer of enameled wire conductors. The radial water-blocking layer is lead foil or lead foil composite tape. The optical fiber core is located in the outer angle space, and the filler fills the gaps in the outer angle space to make the central unit cylindrical.

[0006] The outer layer unit is sleeved on the outside of the central unit. The outer layer unit includes, from the inside out, a cable-forming anti-worm layer, an inner lining layer, an armor layer, and an outer sheath layer.

[0007] Furthermore, both the conductor shielding layer and the insulating shielding layer are made of polypropylene semiconducting shielding material, and the insulating layer is made of polypropylene material. The conductor shielding layer, the insulating layer, and the insulating shielding layer are co-extruded on the outside of the water-blocking conductor.

[0008] Furthermore, both the first longitudinal water-blocking layer and the second longitudinal water-blocking layer are semi-conductive water-absorbing and expanding strips wrapped around the outside of the insulating shielding layer, with the expandable surface of the water-absorbing and expanding strips facing the metal shielding layer.

[0009] Furthermore, the metal shielding layer is a copper wire and copper strip applied to the outside of the first longitudinal water-blocking layer.

[0010] Furthermore, the non-metallic sheath layer is made of polyethylene material, and the non-metallic sheath layer is extruded onto the outside of the radial water-blocking layer.

[0011] Furthermore, the filler is a non-hygroscopic soft material.

[0012] Furthermore, the cable-forming anti-moth layer comprises a high-strength non-woven fabric and a brass strip wrapped around the outside of the non-metallic sheath layer.

[0013] Furthermore, the inner lining layer is a polypropylene rope wrapped around the outside of the cable-forming anti-moth layer, and the outer surface of the inner lining layer is coated with an anti-corrosion layer.

[0014] Furthermore, the armor layer is a corrosion-resistant galvanized low-carbon steel wire applied to the outside of the inner lining layer, and the outer surface of the armor layer is coated with an anti-corrosion layer.

[0015] Furthermore, the outer sheath is a polypropylene rope wrapped around the outside of the armor layer, and an anti-corrosion layer is impregnated on the polypropylene rope.

[0016] Compared with the prior art, the above-mentioned technical solution of this utility model has the following advantages: The 66kV and below submarine cable of this utility model, on the one hand, uses enameled wire conductors. Enameled wire is a plated conductor with good high-temperature resistance, corrosion resistance, and chemical resistance, which can improve the temperature resistance of the cable and indirectly improve the transmission capacity of the product. Enameled wire conductors have low dielectric loss and low skin effect, which improves the overall electrical performance and current carrying capacity of the system. On the other hand, the design of a double-layer longitudinal water-blocking layer improves the longitudinal water-blocking capacity of the product structure, while reducing the indentation of the copper wire on the cable core (copper wire internal structure) during the production of the metal shielding layer (copper wire shield), thus optimizing the product structure. Moreover, the radial water-blocking layer uses lead foil or a lead foil composite structure. The lead foil is produced using a longitudinal wrapping process, eliminating the need for asphalt coating and preventing environmental pollution. The lead foil itself has a certain thickness, which can provide a certain degree of moisture-proof, waterproof, and corrosion-proof protection for the internal structure, and can also bear a portion of the short-circuit current. This invention is primarily intended for use in conventional and harsh environments for both offshore and onshore wind power. It can also be used in low-frequency and power frequency transmission conditions, especially in areas with limited and harsh local installation conditions. The current carrying capacity and transmission capacity of the product are significantly improved. Attached Figure Description

[0017] To make the content of this utility model easier to understand, the present utility model will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0018] Figure 1 This is a schematic diagram of the structure of the submarine cable for 66KV and below in this utility model.

[0019] Explanation of reference numerals in the accompanying drawings: 1. Cable core; 11. Water-blocking conductor; 12. Conductor shielding layer; 13. Insulation layer; 14. Insulation shielding layer; 15. First longitudinal water-blocking layer; 16. Metallic shielding layer; 17. Second longitudinal water-blocking layer; 18. Radial water-blocking layer; 19. Non-metallic sheath layer; 2. Optical cable core; 3. Filler; 4. Cable anti-worm layer; 5. Inner lining layer; 6. Armor layer; 7. Outer sheath layer. Detailed Implementation

[0020] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can better understand and implement the present invention. However, the embodiments are not intended to limit the present invention. Example

[0021] See Figure 1 As shown, this utility model provides an embodiment of a submarine cable with a range of 66kV and below.

[0022] The aforementioned submarine cables of 66kV and below include;

[0023] The central unit includes multiple cable cores 1, at least one optical fiber core 2, and filler 3. The multiple cable cores 1 are evenly distributed around the central axis of the submarine cable, and an outer angle space is formed between two adjacent cable cores 1, away from the center of the submarine cable. The cable core 1 includes, from the inside out, a water-blocking conductor 11, a conductor shielding layer 12, an insulation layer 13, an insulation shielding layer 14, a first longitudinal water-blocking layer 15, a metal shielding layer 16, a second longitudinal water-blocking layer 17, a radial water-blocking layer 18, and a non-metallic sheath layer 19. The water-blocking conductor 11 includes layered stranded enameled wire conductors and salt water-resistant water-blocking tape stranded on each layer of the enameled wire conductors. The radial water-blocking layer 18 is lead foil or lead foil composite tape. The optical fiber core 2 is located in the outer angle space. The filler 3 fills the gap in the outer angle space so that the central unit is cylindrical.

[0024] The outer layer unit is sleeved on the outside of the central unit. The outer layer unit includes, from the inside out, a cable-forming anti-moth layer 4, an inner lining layer 5, an armor layer 6, and an outer sheath layer 7.

[0025] The water-blocking conductor 11 carries current. The conductor shielding layer 12 eliminates electric field concentration on the conductor surface, prevents partial discharge caused by gaps between the insulation layer and the water-blocking conductor, and improves the cable's operating field strength. The insulation layer 13 provides an effective barrier against the extremely high potential difference between the inner and outer potential surfaces. The insulating shielding layer 14 is extruded onto each cable core insulation layer, serving to uniform the electric field and prevent partial discharge caused by gaps between the insulation layer and the metal shield. The first longitudinal water-blocking layer 15, the second longitudinal water-blocking layer 17, and the radial water-blocking layer 18 prevent moisture from entering the cable, thereby ensuring the cable's electrical performance and lifespan. The metal shielding layer 16 is required to carry short circuits in the system. The non-metallic sheath layer 19 enhances waterproofing and corrosion resistance. The aforementioned armor layer 6 strengthens the mechanical strength of the submarine cable and prevents damage from external forces. The aforementioned outer sheath layer 7 resists seawater corrosion and wear during construction.

[0026] Previously, our offshore wind power products used bare conductors or unplated conductors (such as copper core and aluminum core conductors). Plating conductors generally have certain advantages. For example, enameled wire has good high-temperature resistance, corrosion resistance, and chemical resistance, which can improve the temperature resistance of the cable and indirectly improve the transmission capacity of the product. Enameled wire conductors have low dielectric loss and low skin effect, which can improve the overall electrical performance and current carrying capacity of the system.

[0027] Typically, a single longitudinal water-blocking layer is sufficient. However, in actual production, theoretically, designing only one longitudinal water-blocking layer outside the metal shield can also achieve the same effect. This patented design...

[0028] The longitudinal water-blocking layer uses lead foil or a lead foil composite structure. The lead foil is produced using a longitudinal wrapping process, which does not require asphalt coating and will not pollute the environment. The lead foil itself has a certain thickness, which can play a certain role in moisture-proofing, waterproofing, and corrosion prevention for the internal structure, while also being able to withstand a portion of the short-circuit current.

[0029] This structure is primarily intended for use in both conventional and harsh environments for offshore and onshore wind power. It can also be used for low-frequency and power frequency transmission, and its performance is significantly improved, especially under localized, harsh, and limited installation conditions.

[0030] In this embodiment, the conductor shielding layer 12 and the insulating shielding layer 14 are both polypropylene semiconducting shielding materials, the insulating layer 13 is a polypropylene material, and the conductor shielding layer 12, the insulating layer 13 and the insulating shielding layer 14 are co-extruded on the outside of the water-blocking conductor 11.

[0031] Environmentally friendly polypropylene is used as the insulation material, and environmentally friendly semi-conductive polypropylene is used as the shielding material. The conductor shielding layer 12, insulation layer 13, and insulation shielding layer 14 are produced by a three-layer co-extrusion process. The polypropylene material is a non-crosslinked insulation material and does not require degassing, thus eliminating the degassing step and simplifying the production process. Sufficient cooling is ensured during production. There are no by-products in the production of polypropylene insulation material, making it suitable for long-length, continuous extrusion production. Studies have found that polypropylene has good resistance to water treeing, which can inhibit the growth of water treeing in the insulation and reduce the failure rate of cables. It is more suitable for operation under humid and hot conditions and immersion in water.

[0032] In this embodiment, the first longitudinal water-blocking layer 15 and the second longitudinal water-blocking layer 17 are both semi-conductive water-absorbing and expanding strips wrapped around the outside of the insulating shielding layer 14, with the expandable surface of the water-absorbing and expanding strip facing the metal shielding layer 16.

[0033] A semi-conductive water-absorbing and expanding tape is used for longitudinal water blocking to limit seawater seepage along the cable in the event of cable damage. The material is compatible with other adjacent materials. The semi-conductive water-absorbing and expanding tape is tightly and smoothly wrapped, with its expandable surface facing the metal shielding layer, and its thickness sufficient to compensate for thermal expansion during cable operation. This ensures electrical contact between the insulating shielding layer 14 and the metal shielding layer 16.

[0034] In this embodiment, the metal shielding layer 16 is a copper wire and copper strip applied to the outside of the first longitudinal water-blocking layer 15.

[0035] Copper wire and copper strip provide a lightweight structure, while the metal shielding layer needs to withstand the system's short circuit. Based on the system's short-circuit current, a copper wire shielding structure is adopted. This lightweight structure reduces the environmental pollution caused by traditional heavy metal lead sheaths (asphalt corrosion protection).

[0036] In this embodiment, the non-metallic sheath layer 19 is made of polyethylene material, and the non-metallic sheath layer 19 is extruded onto the outside of the radial water-blocking layer 18.

[0037] A non-metallic sheath is extruded onto the radial water-blocking layer 18 to enhance the waterproof function.

[0038] In this embodiment, the filler is a non-hygroscopic soft material, such as PP rope. The gaps are filled with this non-hygroscopic soft material, ensuring a tight, rounded filling and a circular appearance.

[0039] In this embodiment, the above-mentioned cable anti-moth layer 4 includes high-strength non-woven fabric and brass strip wrapped around the outside of the above-mentioned non-metallic sheath layer 19.

[0040] In this embodiment, the inner lining layer 5 is a polypropylene rope wrapped around the outside of the cable anti-moth layer 4, and the outer surface of the inner lining layer 5 is coated with an anti-corrosion layer.

[0041] The inner lining layer 5 is wrapped with polypropylene rope, and the aforementioned anti-corrosion layer is asphalt or other suitable anti-corrosion materials.

[0042] In this embodiment, the armor layer 6 is a corrosion-resistant galvanized low-carbon steel wire applied to the outside of the inner lining layer 5, and the outer surface of the armor layer 6 is coated with an anti-corrosion layer.

[0043] The armor layer 6 is made of specially treated anti-corrosion galvanized low-carbon steel wire laid on the inner lining layer 5. The anti-corrosion layer is made of asphalt material. Asphalt is used on the armor layer to provide further anti-corrosion protection and adhesion of all protective layers. The armor requires a very tight fit, with very small gaps between adjacent metal wires.

[0044] In this embodiment, the outer sheath 7 is a polypropylene rope wrapped around the outside of the armor layer 6, and an anti-corrosion layer is formed on the polypropylene rope.

[0045] The outer sheath 7 is a tightly twisted polypropylene rope. The fourth anti-corrosion layer is asphalt. The polypropylene rope is impregnated with asphalt to form the anti-corrosion layer, which has good wear resistance and is firmly wrapped around the armored metal wire to ensure that the submarine cable does not loosen or slip during movement and construction.

[0046] The above-mentioned method for manufacturing submarine cables of 66kV and below includes the following steps:

[0047] S1. Fabricate the above-mentioned water-blocking conductor 11;

[0048] S2. On the outside of the water-blocking conductor 11, three layers of the conductor shielding layer 12, the insulating layer 13, and the insulating shielding layer 14 are co-extruded.

[0049] S3. The first longitudinal water-blocking layer 15 is formed on the outside of the above-mentioned insulating shielding layer 14;

[0050] S4. The metal shielding layer 16 is made on the outside of the first longitudinal water-blocking layer 15.

[0051] S5. The second longitudinal water-blocking layer 17 is formed on the outside of the metal shielding layer 16.

[0052] S6. The radial water barrier layer 18 is made on the outside of the second longitudinal water barrier layer 17.

[0053] S7. The non-metallic sheath layer 19 is made on the outside of the radial water-blocking layer 18 to obtain the conductor core 1.

[0054] S8. Combining multiple of the above-mentioned conductive cable cores 1, optical fiber cores 2 and filler 3 together to form the above-mentioned central unit;

[0055] S9. Fabricate the above-mentioned cable-forming anti-worm layer 4 on the outside of the above-mentioned central unit;

[0056] S10. The inner lining layer 5 is made on the outside of the above-mentioned cable-forming anti-worm layer 4.

[0057] S11. An armor layer 6 is made on the outside of the inner lining layer 5.

[0058] S12. The outer layer 7 is fabricated on the outside of the armor layer 6.

[0059] Multiple conductive cable cores 1 are manufactured through the above steps S1 to S6. Specifically, in this embodiment, three conductive cable cores 1 are manufactured through the above steps S1 to S6. After manufacturing multiple conductive cable cores of the same submarine cable, the multiple conductive cable cores 1, the optical fiber cores 2, and the filler 3 are combined together.

[0060] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the protection scope of this invention.

Claims

1. A submarine cable with a range of 66kV and below, characterized in that, include; The central unit comprises multiple cable cores, at least one optical fiber core, and filler. The multiple cable cores are evenly distributed around the central axis of the submarine cable, with adjacent cable cores forming an outward-facing angle space away from the center of the cable. Each cable core includes, from the inside out, a water-blocking conductor, a conductor shielding layer, an insulation layer, an insulation shielding layer, a first longitudinal water-blocking layer, a metallic shielding layer, a second longitudinal water-blocking layer, a radial water-blocking layer, and a non-metallic sheath layer. The water-blocking conductor comprises layered stranded enameled wire conductors and... Salt-resistant water-blocking tape stranded on each layer of the enameled wire conductor; the first longitudinal water-blocking layer and the second longitudinal water-blocking layer are both semi-conductive water-absorbing and expanding tapes wrapped around the outside of the insulating shielding layer; the expandable surface of the water-absorbing and expanding tape faces the metal shielding layer; the metal shielding layer is copper wire and copper strip applied to the outside of the first longitudinal water-blocking layer; the radial water-blocking layer is lead foil or lead foil composite tape; the optical cable core is disposed in the outer angle space; the filler fills the gap in the outer angle space to make the central unit cylindrical. The outer layer unit is sleeved on the outside of the central unit. The outer layer unit includes, from the inside out, a cable-forming anti-worm layer, an inner lining layer, an armor layer, and an outer sheath layer.

2. The 66kV and below submarine cable according to claim 1, characterized in that, Both the conductor shielding layer and the insulating shielding layer are made of polypropylene semiconducting shielding material, and the insulating layer is made of polypropylene material. The conductor shielding layer, the insulating layer, and the insulating shielding layer are co-extruded on the outside of the water-blocking conductor.

3. The 66kV and below submarine cable according to claim 1, characterized in that, The non-metallic sheath layer is made of polyethylene material and is extruded onto the outside of the radial water-blocking layer.

4. The 66kV and below submarine cable according to claim 1, characterized in that, The filler is a non-hygroscopic, soft material.

5. The 66kV and below submarine cable according to claim 1, characterized in that, The cable-forming anti-worm layer includes a high-strength non-woven fabric and a brass strip wrapped around the outside of the non-metallic sheath layer.

6. The 66kV and below submarine cable according to claim 1, characterized in that, The inner lining layer is a polypropylene rope wrapped around the outside of the cable-forming mothproof layer.

7. The 66kV and below submarine cable according to claim 1, characterized in that, The armor layer is a corrosion-resistant galvanized low-carbon steel wire applied to the outside of the inner lining layer, and the outer surface of the armor layer is coated with an anti-corrosion layer.

8. The 66kV and below submarine cable according to claim 1, characterized in that, The outer sheath is a polypropylene rope wrapped around the outside of the armor layer, and an anti-corrosion layer is impregnated on the polypropylene rope.

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