High-voltage torsion-resistant flexible cable, manufacturing method therefor and use thereof

Abstract

A high-voltage torsion-resistant flexible cable for a wind turbine generator set having a rated voltage of 132 kV, a manufacturing method therefor and the use thereof. The high-voltage torsion-resistant flexible cable comprises a metal conductor, the metal conductor being successively coated with a semi-conductive nylon tape, a conductor shielding layer, an insulating layer, an insulation shielding layer, a semi-conductive water blocking tape, a metal shielding layer, an isolation tape and an outer sheath, wherein the material of the outer sheath layer is a thermosetting elastomer sheath material.

Description

High-voltage torsion-resistant flexible cable and its preparation method and application

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on July 24, 2023, with application number 202310906160.1, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present application belongs to the field of cable technology, and for example relates to a high-voltage torsion-resistant flexible cable and its preparation method and application. Background Art

[0003] In recent years, with the rapid development of offshore wind power technology, the capacity of offshore wind turbines has been upgraded from the early 3-4 MW to larger models such as 8-10 MW. In the future, the capacity of individual turbines will further increase, potentially reaching over 20 MW. High-voltage power transmission can effectively improve wind turbine output efficiency, reduce current, significantly reduce line losses, and minimize power loss in transmission cables.

[0004] Currently, wind farm power collection lines commonly used at home and abroad primarily use 35kV or 66kV voltage systems. Related art discloses a highly elastic, torsion-resistant wind power cable with a rated voltage of 6 to 35kV. The cable core is composed of three power insulation cores and three ground insulation cores twisted together. The cable cores are then wrapped with a double layer of alkali-free glass fiber tape and extruded with a thermoplastic elastomer outer sheath. The outermost layer of the cable is a braided layer of stainless steel wire and polyester synthetic fiber yarn. The power insulation core is composed of a conductor twisted together with tinned oxygen-free copper wire and stainless steel wire. The conductor is then wrapped with a single layer of semi-conductive cotton tape. The power insulation core is composed of a three-layer co-extruded conductor shielding layer, an EPDM rubber insulation layer, and an insulating shielding layer. The ground insulation core conductor is extruded with a semi-conductive rubber shielding layer. The cable described in the related art has high tensile strength, high flexibility, high wear resistance, oil resistance, aging resistance, and resistance to external weather. It is suitable for use at the connection between turbines and towers in high-power wind power generation equipment, or in similar applications.

[0005] However, with the rapid increase in the capacity of individual offshore wind turbines, the 66kV voltage system of the wind farm collection line in related technologies will not be able to meet the power transmission needs of ultra-large power wind turbines. 110kV and 132kV offshore array collection high-voltage submarine cables are currently under development, but the matching 132kV dedicated wind turbine high-voltage cable is still missing. The high-voltage torsion-resistant flexible cable for wind turbines with a rated voltage of 132kV is mainly used in ultra-large power wind turbines above 20MW. It connects the nacelle transformer and the switchgear at the base of the tower to achieve power transmission. The length of a single cable is about 180 meters, and three cables are grouped together to form three-phase lines A, B and C. The cable is hoisted and laid as a whole and freely suspended (from the nacelle to the saddle platform at the top of the tower). It has the application function of torsion resistance. Compared with 35kV or 66kV voltage systems, it can reduce the number of array transmission circuits, thereby reducing the wiring complexity of the offshore substation, and even reducing or eliminating the offshore substation, ultimately reducing the owner's investment and operation and maintenance costs.

[0006] In addition, the current wind power torsion-resistant cables generally use chlorosulfonated polyethylene or neoprene as the sheath protective layer, but the high cost of these two materials directly leads to high manufacturing costs of the cables, which have no competitive advantage in the affordable wind power market. At the same time, high-voltage torsion-resistant soft cables for 132kV wind turbines are mostly used in ultra-high-power wind turbines far away from the coast. The offshore environment is particularly harsh, with strong salt spray corrosion, high temperature and high humidity. Harmful substances such as mold are easily bred during cable operation. Therefore, there is an urgent need for an affordable elastomer sheath material that can meet market bidding needs and has the characteristics of mold resistance and salt spray corrosion resistance.

[0007] In summary, developing a high-voltage torsion-resistant flexible cable with excellent mildew resistance and salt spray resistance for a wind turbine with a rated voltage of 132kV is a technical problem that needs to be solved urgently in this field.

[0008] Summary of the Invention

[0009] The present application provides a high-voltage torsion-resistant flexible cable, a preparation method, and an application thereof. The high-voltage torsion-resistant flexible cable is suitable for wind turbines with a rated voltage of 132kV. Through reasonable design of the structure and reasonable selection of materials, it can not only meet the power transmission requirements of the high-voltage torsion-resistant flexible cable under normal working conditions, but also has excellent salt spray resistance and mildew resistance, and can meet the extremely harsh marine use environment.

[0010] In a first aspect, an embodiment of the present application provides a high-voltage torsion-resistant flexible cable, comprising a metal conductor, the metal conductor being sequentially coated with a semi-conductive nylon tape, a conductor shielding layer, an insulating layer, an insulating shielding layer, a semi-conductive water-resistant tape, a metal shielding layer, an isolation tape, and an outer sheath;

[0011] The outer sheath is made of a thermosetting elastomer sheath material, which comprises the following components in parts by weight:

[0012] In a second aspect, an embodiment of the present application provides a method for preparing the high-voltage torsion-resistant flexible cable as described in the first aspect, the method comprising the following steps:

[0013] overlapping and wrapping a semi-conductive nylon tape around a metal conductor to obtain a wrapped metal conductor;

[0014] Extruding the material of the conductor shielding layer, the material of the insulating layer and the material of the insulating shielding layer together on the outside of the wrapped metal conductor to obtain an insulated metal conductor;

[0015] Overlapping and wrapping a semi-conductive water-resistant tape around the insulating metal conductor to obtain a wire core;

[0016] The material of the metal shielding layer is wound around the wire core in a spiral manner to obtain a cable core;

[0017] Overlapping the isolation tape around the cable core to obtain a nascent cable;

[0018] The material of the outer sheath is extruded and wrapped around the primary cable to obtain the high-voltage torsion-resistant flexible cable.

[0019] In a third aspect, an embodiment of the present application provides an application of the high-voltage torsion-resistant flexible cable as described in the first aspect in an offshore wind turbine with a rated voltage of 132 kV. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] FIG1 is a schematic cross-sectional view of a high-voltage torsion-resistant flexible cable for a wind turbine generator system with a rated voltage of 132 kV provided in an embodiment of the present application;

[0021] FIG2 is a flow chart of a method for preparing a high-voltage torsion-resistant flexible cable provided in an embodiment of the present application.

[0022] Among them, 1-metal conductor, 2-semi-conductive nylon tape, 3-conductor shielding layer, 4-insulating layer, 5-insulating shielding layer, 6-semi-conductive water-resistant tape, 7-metal shielding layer, 8-isolation tape, 9-outer sheath. DETAILED DESCRIPTION

[0023] Preparation Examples 1 to 7 and Comparative Preparation Examples 1 to 2

[0024] A high-voltage, torsion-resistant flexible cable for use in wind turbines with a rated voltage of 132 kV comprises a metal conductor, which is sequentially coated with a semi-conductive nylon tape, a conductor shielding layer, an insulating layer, an insulating shielding layer, a semi-conductive water-resistant tape, a metal shielding layer, an isolation tape, and an outer sheath. The outer sheath is made of a thermosetting elastomer sheathing material, including the components shown in Table 1, where the amount of each component is expressed in parts by weight:

[0025] Table 1

[0026] The preparation methods of the thermosetting elastomer sheath materials provided in Preparation Examples 1 to 7 and Comparative Preparation Examples 1 to 2 include the following steps:

[0027] (1) Chlorinated polyethylene (CM135B, Hangzhou Keli) and polyolefin elastomer (POE) (DF640, Ningbo Tianyuan) were mixed at 100°C for 2 min to obtain a rubber compound;

[0028] (2) adding magnesium hydroxide, antimony trioxide, white carbon black, fine kaolin, light magnesium oxide, trioctyl trimellitate, dioctyl sebacate, antioxidant RD, red lead masterbatch, stabilizer (Changzhou Youjia, HL001), stearic acid, high wear-resistant carbon black N-330 and coupling agent KH-550 to the mixed rubber obtained in step (1) and continuing to mix for 4 minutes to obtain primary rubber; wherein the particle size D of the fine kaolin is ≤2.5 kaolin.

[0029] (3) adding diisopropylbenzene peroxide and triallyl isocyanurate to the raw rubber obtained in step (2) and continuing to mix for 1 minute, thinning through 3 times, swinging the rubber 3 times, and cutting into sheets on a three-roll calender. The output rubber is cooled by a cooling roller to obtain the thermosetting elastomer sheath material.

[0030] Example 1

[0031] A high-voltage torsion-resistant flexible cable for a wind turbine with a rated voltage of 132 kV, the cross-sectional structure of which is shown in FIG1 , comprises a metal conductor 1, which is sequentially covered with a semi-conductive nylon tape 2, a conductor shielding layer 3, an insulating layer 4, an insulating shielding layer 5, a semi-conductive water-resistant tape 6, a metal shielding layer 7, an isolation tape 8, and an outer sheath 9;

[0032] The outer sheath 9 is made of a thermosetting elastomer sheath material, which comprises the following components in parts by weight:

[0033] Wherein, the chlorinated polyethylene can be 100 parts by weight, 110 parts by weight, 120 parts by weight, 130 parts by weight or 140 parts by weight, etc.; the elastomer POE can be 5 parts by weight, 6 parts by weight, 7 parts by weight, 8 parts by weight, 9 parts by weight, 10 parts by weight, 11 parts by weight, 12 parts by weight, 13 parts by weight, 14 parts by weight or 15 parts by weight, etc.; the flame retardant can be 20 parts by weight, 22 parts by weight, 24 parts by weight, 26 parts by weight, 28 parts by weight, 30 parts by weight, 32 parts by weight, 34 parts by weight, 36 parts by weight, 38 parts by weight or 40 parts by weight, etc.; the white carbon black can be 15 parts by weight, 16 parts by weight, , 17 parts by weight, 18 parts by weight, 19 parts by weight, 20 parts by weight, 21 parts by weight, 22 parts by weight, 23 parts by weight, 24 parts by weight, or 25 parts by weight, etc.; the filler can be 40 parts by weight, 42 parts by weight, 44 parts by weight, 46 parts by weight, 48 parts by weight, 50 parts by weight, 52 parts by weight, 54 parts by weight, 56 parts by weight, 58 parts by weight, or 60 parts by weight, etc.; the plasticizer can be 15 parts by weight, 16 parts by weight, 17 parts by weight, 18 parts by weight, 19 parts by weight, or 20 parts by weight, etc.; the vulcanizing agent can be 5 parts by weight, 6 parts by weight, 7 parts by weight, 8 parts by weight, 9 parts by weight, or 10 parts by weight, etc.

[0034] The material of the outer sheath of a high-voltage torsion-resistant flexible cable provided in an embodiment of the present application is a thermosetting elastomer sheath material. The thermosetting elastomer sheath material is composed of chlorinated polyethylene and elastomer POE as a base material, and is combined with flame retardants, white carbon black, fillers, vulcanizers, plasticizers and other additives. It combines the performance of various raw materials, takes advantage of their strengths and overcomes their weaknesses, and has excellent aging resistance, high and low temperature resistance, high strength, salt spray corrosion resistance, oil resistance, mildew resistance and other properties, and has reduced costs. It is used in ultra-high power wind turbines far away from the coast. Facing the harsh environment at sea, it has strong resistance to salt spray corrosion, high temperature and high humidity, and is not easy to breed harmful substances such as mildew during operation. It can meet both market bidding requirements and the operation requirements of wind turbines with a rated voltage of 132kV.

[0035] The metal conductor 1 is a Type 5 round stranded tinned soft copper conductor specified in GB / T 3956. The conductor surface is smooth and free of burrs, sharp edges, protrusions, or broken single wires that damage the insulation.

[0036] The material of the semi-conductive nylon tape layer 2 is semi-conductive nylon tape (from Yangzhou Tengfei, brand BNLD 12);

[0037] The material of the conductor shielding layer 3 is imported ultra-clean semi-conductive inner shielding material (from TRELLEBORG, brand E6595), and its performance complies with the requirements of IEC 60840 standard;

[0038] The material of the insulation layer 4 is imported 150kV ultra-clean EPR insulation material (from Mixer SpA, brand 3IS721), and its performance meets the requirements of IEC 60840 standard;

[0039] The material of the insulating shielding layer 5 is imported ultra-clean semi-conductive inner shielding material (from TRELLEBORG, brand E6595), and its performance meets the requirements of IEC 60840 standard;

[0040] The material of the semi-conductive water-resistant tape 6 is a semi-conductive water-resistant tape (from Yangzhou Tengfei, brand ZDBS);

[0041] The material of the metal shielding layer 7 is a combination of tinned round copper wire and polyester composite fiber yarn with a mass ratio of 8.89:1.14, which plays the role of metal shielding the ground fault current while enhancing the torsional and tensile resistance of the shielding layer;

[0042] The material of the isolation belt 8 is a non-hygroscopic isolation belt (from Yangzhou Tengfei, brand WFB);

[0043] The material of the outer sheath 9 is the thermosetting elastomer sheath material obtained in Preparation Example 1.

[0044] Exemplarily, the flame retardant includes magnesium hydroxide and antimony trioxide.

[0045] The content of magnesium hydroxide in the thermosetting elastomer sheath material is 10 to 20 parts by weight, for example, 10 parts by weight, 12 parts by weight, 14 parts by weight, 16 parts by weight, 18 parts by weight, or 20 parts by weight.

[0046] The content of antimony trioxide in the thermosetting elastomer sheath material is 10 to 20 parts by weight, for example, 10 parts by weight, 12 parts by weight, 14 parts by weight, 16 parts by weight, 18 parts by weight, or 20 parts by weight.

[0047] Exemplarily, the filler includes fine kaolin and light magnesium oxide.

[0048] The content of fine kaolin in the thermosetting elastomer sheath material is 30 to 40 parts by weight, for example, 30 parts by weight, 32 parts by weight, 34 parts by weight, 36 parts by weight, 38 parts by weight, or 40 parts by weight.

[0049] The content of lightweight magnesium oxide in the thermosetting elastomer sheath material is 10 to 20 parts by weight, for example, 10 parts by weight, 12 parts by weight, 14 parts by weight, 16 parts by weight, 18 parts by weight, or 20 parts by weight.

[0050] Exemplarily, the plasticizer includes trioctyl trimellitate and dioctyl sebacate.

[0051] The content of trioctyl trimellitate in the thermosetting elastomer sheath material is 8 to 10 parts by weight, for example, 8 parts by weight, 8.2 parts by weight, 8.4 parts by weight, 8.6 parts by weight, 8.8 parts by weight, 9 parts by weight, 9.2 parts by weight, 9.4 parts by weight, 9.6 parts by weight, 9.8 parts by weight, or 10 parts by weight.

[0052] The content of dioctyl sebacate in the thermosetting elastomer sheath material is 7 to 10 parts by weight, for example, 7 parts by weight, 7.5 parts by weight, 8 parts by weight, 8.5 parts by weight, 9 parts by weight, 9.5 parts by weight, or 10 parts by weight.

[0053] Exemplarily, the vulcanizing agent includes dicumyl peroxide and triallyl isocyanurate.

[0054] The content of dicumyl peroxide in the thermosetting elastomer sheath material is 3 to 5 parts by weight, for example, 3 parts by weight, 3.2 parts by weight, 3.4 parts by weight, 3.6 parts by weight, 3.8 parts by weight, 4 parts by weight, 4.2 parts by weight, 4.4 parts by weight, 4.6 parts by weight, 4.8 parts by weight, or 5 parts by weight.

[0055] The content of triallyl isocyanurate in the thermosetting elastomer sheathing material is 2 to 5 parts by weight, for example, 2 parts by weight, 2.5 parts by weight, 3 parts by weight, 3.5 parts by weight, 4 parts by weight, 4.5 parts by weight, or 5 parts by weight.

[0056] Exemplarily, the thermosetting elastomer sheathing material further includes any one or a combination of at least two of an antioxidant, red lead masterbatch, a stabilizer, stearic acid, carbon black or a coupling agent.

[0057] The content of the antioxidant in the thermosetting elastomer sheath material is 2 to 4 parts by weight, for example, 2 parts by weight, 2.2 parts by weight, 2.4 parts by weight, 2.6 parts by weight, 2.8 parts by weight, 3 parts by weight, 3.2 parts by weight, 3.4 parts by weight, 3.6 parts by weight, 3.8 parts by weight, or 4 parts by weight.

[0058] The content of red lead masterbatch in the thermosetting elastomer sheath material is 4 to 6 parts by weight, for example, 4 parts by weight, 4.2 parts by weight, 4.4 parts by weight, 4.6 parts by weight, 4.8 parts by weight, 5 parts by weight, 5.2 parts by weight, 5.4 parts by weight, 5.6 parts by weight, 5.8 parts by weight, or 6 parts by weight.

[0059] The content of the stabilizer in the thermosetting elastomer sheath material is 8 to 12 parts by weight, for example, 8 parts by weight, 8.5 parts by weight, 9 parts by weight, 9.5 parts by weight, 10 parts by weight, 10.5 parts by weight, 11 parts by weight, 11.5 parts by weight, or 12 parts by weight.

[0060] The content of stearic acid in the thermosetting elastomer sheath material is 0.5 to 1.5 parts by weight, for example, 0.5 parts by weight, 0.6 parts by weight, 0.7 parts by weight, 0.8 parts by weight, 0.9 parts by weight, 1 part by weight, 1.1 parts by weight, 1.2 parts by weight, 1.3 parts by weight, 1.4 parts by weight, or 1.5 parts by weight.

[0061] The content of carbon black in the thermosetting elastomer sheath material is 2 to 3 parts by weight, for example, 2 parts by weight, 2.2 parts by weight, 2.4 parts by weight, 2.6 parts by weight, 2.8 parts by weight, or 3 parts by weight.

[0062] The content of the coupling agent in the thermosetting elastomer sheath material is 1 to 3 parts by weight, for example, 1 part by weight, 1.2 parts by weight, 1.4 parts by weight, 1.6 parts by weight, 1.8 parts by weight, 2 parts by weight, 2.2 parts by weight, 2.4 parts by weight, 2.6 parts by weight, 2.8 parts by weight, or 3 parts by weight.

[0063] Exemplarily, the thermosetting elastomer sheath material is prepared by the following method, which includes the following steps:

[0064] (A1) mixing chlorinated polyethylene and elastomer POE to obtain a rubber compound;

[0065] (A2) mixing the rubber mix obtained in step (A1), a flame retardant, white carbon black, a filler, a plasticizer, optionally an antioxidant, optionally a red lead masterbatch, optionally a stabilizer, optionally stearic acid, optionally carbon black, and optionally a coupling agent to obtain a primary rubber;

[0066] (A3) mixing the raw rubber obtained in step (A2) with a vulcanizing agent to obtain the thermosetting elastomer sheath material.

[0067] As an exemplary technical solution of the present application, the thermosetting elastomer sheath material is prepared by the following method, which includes the following steps:

[0068] (B1) mixing chlorinated polyethylene and elastomer POE at 100±5% for 1 to 2 minutes (e.g., 1 minute, 1.2 minutes, 1.4 minutes, 1.6 minutes, 1.8 minutes, or 2 minutes) to obtain a rubber compound;

[0069] (B2) adding a flame retardant, white carbon black, a filler, a plasticizer, optionally an antioxidant, optionally a red lead masterbatch, optionally a stabilizer, optionally stearic acid, optionally carbon black, and optionally a coupling agent to the rubber mix obtained in step (B1), and continuing to mix for 3 to 4 minutes (e.g., 3 minutes, 3.2 minutes, 3.4 minutes, 3.6 minutes, 3.8 minutes, or 4 minutes, etc.) to obtain a primary rubber;

[0070] (B3) mixing the virgin rubber obtained in step (B2) with a vulcanizing agent for 0.5 to 1 min (e.g., 0.5 min, 0.6 min, 0.7 min, 0.8 min, 0.9 min, or 1 min, etc.), thinning the rubber 2 to 3 times, swinging the rubber 2 to 3 times, and rolling the rubber into sheets on a three-roll calender. The output rubber is cooled by a cooling roller to obtain the thermosetting elastomer sheathing material.

[0071] Exemplarily, the metal conductor is a tinned soft copper conductor.

[0072] The tinned soft copper conductor is the fifth type of round stranded tinned soft copper conductor specified in GB / T 3956 standard. The conductor surface is smooth and has no burrs, sharp edges or protruding or broken single wires that damage the insulation.

[0073] The material of the insulation layer is 150kV grade high-density polyethylene (HEPR) insulation material;

[0074] As an example technical solution of the present application, the material of the insulating layer adopts high-purity HEPR insulating material, and the material voltage level can reach 150kV. At the same time, it matches the high-purity and high-conductivity conductor shielding layer and the insulating shielding layer, and through the reasonable size design of the insulating layer and the shielding layer, the physical and electrical properties of the insulated wire core are effectively guaranteed.

[0075] The material of the metal shielding layer includes tinned round copper wire and polyester composite fiber wire (for example, polyester fiber), which can meet the requirements of torsion resistance and ground fault current carrying capacity.

[0076] This embodiment provides a method for preparing a high-voltage torsion-resistant flexible cable, as shown in FIG2 , comprising the following steps:

[0077] (1) wrapping a semiconductor electrical nylon tape around a metal conductor to obtain a wrapped metal conductor; wherein the overlap rate may be 25%;

[0078] (2) extruding the material of the conductor shielding layer, the material of the insulating layer, and the material of the insulating shielding layer together on the outside of the wrapped metal conductor obtained in step (1) to obtain an insulated metal conductor;

[0079] (3) wrapping a semi-conductive water-resistant tape over the insulated metal conductor obtained in step (2) to obtain a wire core; wherein the overlap rate can be 25%;

[0080] (4) Wrapping the material of the metal shielding layer around the wire core obtained in step (3) in a spiral winding manner to obtain a cable core;

[0081] (5) wrapping the isolation tape over the cable core obtained in step (4) to obtain a newly formed cable; wherein the overlap rate can be 25%;

[0082] (6) Extruding the material of the outer sheath onto the primary cable obtained in step (5) to obtain the high-voltage torsion-resistant flexible cable.

[0083] An embodiment of the present application provides an application of the high-voltage torsion-resistant flexible cable described in the aforementioned embodiment in an offshore wind turbine with a rated voltage of 132 kV.

[0084] The embodiment of the present application provides a high-voltage torsion-resistant flexible cable for a wind turbine with a rated voltage of 132kV, including a metal conductor, which is sequentially coated with a semi-conductive nylon tape, a conductor shielding layer, an insulating layer, an insulating shielding layer, a semi-conductive water-resistant tape, a metal shielding layer, an isolation tape and an outer sheath; wherein the material of the outer sheath is a thermosetting elastomer sheathing material, which is composed of a base material of chlorinated polyethylene and an elastomer POE, and is combined with a flame retardant, white carbon black, a filler, a vulcanizer, a plasticizer and other additives, and comprehensively combines the performance of various raw materials to make up for their shortcomings. It has excellent aging resistance, high and low temperature resistance, high strength, salt spray corrosion resistance, oil resistance, mildew resistance and other properties, and has reduced cost. It is used in ultra-high power wind turbines far away from the coast, can meet the operation requirements of wind turbines with a rated voltage of 132kV, and is not easy to breed harmful substances such as mildew during operation. It also has the characteristics of strong resistance to salt spray corrosion and resistance to high temperature and high humidity.

[0085] Examples 2 to 7

[0086] A high-voltage, torsion-resistant flexible cable for a wind turbine with a rated voltage of 132 kV is disclosed. The cable differs from Example 1 only in that the thermosetting elastomer sheath material obtained in Preparation Examples 2 to 7 is used as the material for the outer sheath instead of the thermosetting elastomer sheath material obtained in Example 1. The other structures, materials, and preparation methods are the same as those in Example 1.

[0087] Example 8

[0088] An embodiment of the present application provides a high-voltage torsion-resistant flexible cable for a wind turbine with a rated voltage of 132 kV. The only difference between the cable and Example 1 is that the material of the metal shielding layer 7 is only tinned round copper wire, and no polyester composite fiber yarn is added. The other structures, materials and preparation methods are the same as those in Example 1.

[0089] Comparative Examples 1-2

[0090] A high-voltage, torsion-resistant flexible cable for a wind turbine with a rated voltage of 132 kV is disclosed. The cable differs from Example 1 only in that the thermosetting elastomer sheath material obtained in Comparative Preparation Examples 1 to 2 is used as the material for the outer sheath instead of the thermosetting elastomer sheath material obtained in Example 1. The other structures, materials, and preparation methods are the same as those in Example 1.

[0091] Performance testing:

[0092] (1) Salt spray resistance: Tested according to the test method provided in Appendix F of GB / T 33606;

[0093] (2) Flame retardancy: Tested according to the test method provided in GB / T 18380 for bundle combustion;

[0094] (3) Fungus resistance: Test according to the test method provided in GJB 150.10A;

[0095] (4) Anti-torsion performance: Test according to the test method provided in "Q / 320584PDH203-2023".

[0096] The high-voltage torsion-resistant flexible cables provided in Examples 1 to 8 and Comparative Examples 1 to 2 were tested according to the above test method. The test results are shown in Table 2:

[0097] Table 2

[0098] According to the data in Table 2, we can see that:

[0099] The high-voltage torsion-resistant flexible cable provided in the embodiment of the present application has excellent salt spray resistance, flame retardancy, mildew resistance and torsion resistance.

[0100] The high-voltage torsion-resistant flexible cables provided in Examples 1 to 3 can all pass the salt spray resistance test, flame retardancy B, and mildew resistance can reach level 0. The anti-torsion test shows that the broken wire rate is less than 10%, and the torsion test is passed.

[0101] The high-voltage torsion-resistant flexible cable obtained in Comparative Example 1 failed the salt spray resistance test, and the torsion resistance test showed that the surface was twisted. The reason for failing the torsion test was that the thermosetting elastomer sheath material used did not contain the elastomer POE, but only chlorinated polyethylene.

[0102] The torsion test of the high-voltage torsion-resistant flexible cable obtained in Comparative Example 2 showed that the broken wire rate was less than 10%. The failure of the torsion test was caused by too low addition of chlorinated polyethylene in the thermosetting elastomer sheath material used.

[0103] The thermosetting elastomer sheath material of the high-voltage torsion-resistant flexible cable provided in Examples 4 and 5 uses only a single flame retardant, thereby reducing the flame retardancy.

[0104] The thermosetting elastomer sheath material of the high-voltage torsion-resistant flexible cable provided in Examples 6 and 7 uses only a single plasticizer, which results in a decrease in fungus resistance.

[0105] The metal shielding layer of the thermosetting elastomer sheath material of the high-voltage torsion-resistant flexible cable provided in Example 8 is made of only tinned round copper wire, resulting in poor torsion resistance.

Claims

1. A high-voltage torsion-resistant flexible cable, comprising a metal conductor, the metal conductor being coated with a semi-conductive nylon tape, a conductor shielding layer, an insulating layer, an insulating shielding layer, a semi-conductive water-resistant tape, a metal shielding layer, an isolation tape and an outer sheath in sequence; The material of the outer sheath is a thermosetting elastomer sheath material, and the thermosetting elastomer sheath material comprises the following components in parts by weight:

2. The high voltage torsion resistant flexible cable according to claim 1, wherein: The flame retardant includes magnesium hydroxide and antimony trioxide; The content of magnesium hydroxide in the thermosetting elastomer sheath material is 10 to 20 parts by weight; The content of antimony trioxide in the thermosetting elastomer sheath material is 10 to 20 parts by weight.

3. The high voltage torsion resistant flexible cable according to claim 1 or 2, wherein: The filler includes fine kaolin and light magnesium oxide; The content of fine kaolin in the thermosetting elastomer sheath material is 30 to 40 parts by weight; The content of light magnesium oxide in the thermosetting elastomer sheath material is 10 to 20 parts by weight.

4. The high voltage torsion resistant flexible cable according to any one of claims 1 to 3, wherein: The plasticizer includes trioctyl trimellitate and dioctyl sebacate; The content of trioctyl trimellitate in the thermosetting elastomer sheath material is 8 to 10 parts by weight; The content of dioctyl sebacate in the thermosetting elastomer sheath material is 7 to 10 parts by weight.

5. The high voltage torsion resistant flexible cable according to any one of claims 1 to 4, wherein: The vulcanizing agent includes dicumyl peroxide and triallyl isocyanurate; The content of dicumyl peroxide in the thermosetting elastomer sheath material is 3 to 5 parts by weight; The content of triallyl isocyanurate in the thermosetting elastomer sheath material is 2 to 5 parts by weight.

6. The high voltage torsion resistant flexible cable according to any one of claims 1 to 5, wherein: The thermosetting elastomer sheath material further comprises at least one of the following: an antioxidant, red lead masterbatch, a stabilizer, stearic acid, carbon black, and a coupling agent; The content of the antioxidant in the thermosetting elastomer sheath material is 2 to 4 parts by weight; The content of red lead masterbatch in the thermosetting elastomer sheath material is 4 to 6 parts by weight; The content of the stabilizer in the thermosetting elastomer sheath material is 8 to 12 parts by weight; The content of stearic acid in the thermosetting elastomer sheath material is 0.5 to 1.5 parts by weight; The content of carbon black in the thermosetting elastomer sheath material is 2 to 3 parts by weight; The content of the coupling agent in the thermosetting elastomer sheath material is 1 to 3 parts by weight.

7. The high voltage torsion resistant flexible cable according to any one of claims 1 to 6, wherein: The thermosetting elastomer sheath material is prepared by the following method: Mixing the chlorinated polyethylene and the polyolefin elastomer POE to obtain a rubber mixture; The mixed rubber, the flame retardant, the white carbon black, the filler, the plasticizer, the antioxidant, the red lead masterbatch, the stabilizer, stearic acid, carbon black and the coupling agent are mixed to obtain a primary rubber; The primary rubber and the vulcanizing agent are mixed to obtain the thermosetting elastomer sheath material.

8. The high voltage torsion resistant flexible cable according to any one of claims 1 to 7, wherein: The metal conductor is a tinned soft copper conductor; The material of the insulating layer is 150kV grade high-density polyethylene HEPR insulating material; The material of the metal shielding layer includes tinned round copper wire and polyester composite fiber wire.

9. A method for preparing a high voltage torsion resistant flexible cable according to any one of claims 1 to 8, comprising: Overlapping and wrapping a semi-conductive nylon tape around a metal conductor to obtain a wrapped metal conductor; Extruding the material of the conductor shielding layer, the material of the insulating layer and the material of the insulating shielding layer together outside the wrapped metal conductor to obtain an insulated metal conductor; Overlapping and wrapping a semi-conductive water-resistant tape around the insulating metal conductor to obtain a wire core; The material of the metal shielding layer is wound around the wire core in a spiral manner to obtain a cable core; Overlapping and wrapping the isolation tape around the cable core to obtain a primary cable; The material of the outer sheath is extruded and wrapped outside the primary cable to obtain the high-voltage torsion-resistant soft cable.

10. Use of the high-voltage torsion-resistant flexible cable according to any one of claims 1 to 8 in an offshore wind turbine with a rated voltage of 132 kV.

Images