Flexible high-temperature-resistant radio-frequency high-voltage cable and preparation method thereof

Abstract

The invention relates to the technical field of cable manufacturing, in particular to a flexible high-temperature-resistant radio-frequency high-voltage cable and a preparation method thereof. The cable comprises an inner conductor, an insulating layer, a shielding layer and a sheath layer, the inner conductor is configured to be formed by twisting a plurality of nickel-plated tin-copper alloy monofilaments; the insulating layer wraps the outer side of the inner conductor, and the insulating layer is configured to be a polyimide film; the shielding layer wraps the outer side of the insulating layer, the shielding layer comprises a silver-plated copper strip braid layer, a silver-plated copper wire braid layer and a polyimide aluminum composite film, and the polyimide aluminum composite film is located between the silver-plated copper strip braid layer and the silver-plated copper wire braid layer; the sheath layer wraps the outer side of the shielding layer. The cable can realize stable transmission of signals in a high-temperature environment, and has better structural reliability on the basis of ensuring flexibility.

Description

Technical Field

[0001] This application relates to the field of cable manufacturing technology, specifically to a flexible high-temperature resistant radio frequency high-voltage cable and its preparation method. Background Technology

[0002] High-voltage applications typically involve voltage levels exceeding 100,000 volts or even higher. Many of these applications may involve sensing in high-voltage power distribution systems, such as public power grids, but numerous scientific research and medical applications also utilize extremely high voltages. Many of these applications require equipment to handle voltage levels of 20kV or even higher than 40kV, thus necessitating high-voltage radio frequency cables.

[0003] Therefore, components designed specifically for high-voltage applications, such as high-voltage connectors and adapters, high-voltage coaxial cables, and high-voltage DC blockers, offer higher voltage levels and more attractive features compared to standard coaxial components.

[0004] In electrical / electronic systems, there is an unavoidable relationship between power, voltage, and current. High voltage is required to carry as much power as possible with minimal conductivity loss. In high-voltage applications, specific design techniques and materials are needed to ensure that voltage breakdown does not occur; this is where high-voltage radio frequency coaxial cables come in.

[0005] Existing radio frequency cables typically use double or multiple layers of metal braided shielding, which generally provides only moderate shielding effectiveness. In particular, under high temperature and high pressure conditions, the stability of transmission performance needs to be improved. Summary of the Invention

[0006] This application provides a flexible high-temperature resistant radio frequency high-voltage cable and its manufacturing method. By adding a metal composite film between the two metal braided layers to isolate the metal braided layers, the shielding effect of the shielding layer is improved, while ensuring good heat dissipation performance of the cable, so that it can maintain stable transmission performance under high temperature and high pressure environment.

[0007] This application is achieved through the following technical solution:

[0008] In a first aspect, this application provides a flexible high-temperature resistant radio frequency high-voltage cable, comprising:

[0009] The inner conductor is configured to be formed by stranding multiple nickel-tin-copper alloy monofilaments;

[0010] An insulating layer, the insulating layer being wrapped around the outside of the inner conductor, wherein the insulating layer is configured as a polyimide film;

[0011] A shielding layer is wrapped around the outside of the insulating layer. The shielding layer includes a silver-plated copper strip braided layer, a silver-plated copper wire braided layer, and a polyimide aluminum composite film, wherein the polyimide aluminum composite film is located between the silver-plated copper strip braided layer and the silver-plated copper wire braided layer.

[0012] A sheath layer, which is wrapped around the outside of the shielding layer.

[0013] In some optional embodiments, the diameter of the nickel-tin-copper alloy monofilament is configured to be 0.5 mm to 4.5 mm.

[0014] In some optional embodiments, the width of the copper strip in the silver-plated copper strip braid is configured to be 0.8 mm to 3.5 mm.

[0015] In some alternative embodiments, the surface of the insulating layer away from the inner conductor has a fluoroplastic coating.

[0016] In some alternative embodiments, the fluoroplastic coating is a perfluoroethylene propylene layer.

[0017] In some alternative embodiments, the sheath layer is configured as a fluororubber layer treated by a vulcanization process.

[0018] In some optional embodiments, the nickel plating thickness of the nickel-tin-copper alloy monofilament surface layer is 3 μm.

[0019] In some alternative embodiments, the thickness of the insulating layer is configured to be 0.051 mm to 0.254 mm.

[0020] In some alternative embodiments, the insulating layer is configured to be formed by a multi-layer wrapping process, wherein the wrapping overlap is 50%.

[0021] Secondly, this application provides a method for manufacturing a flexible high-temperature resistant radio frequency high-voltage cable, comprising the following:

[0022] The inner conductor is formed by stranding nickel-tin-copper alloy wires.

[0023] An insulating layer is formed by wrapping a polyimide film around the inner conductor, wherein the wrapping speed is 160 r / min to 200 r / min and the overlap rate is 50%.

[0024] Silver-plated copper strips are woven around the insulation layer, wherein the coverage of the silver-plated copper strips is not less than 90%.

[0025] A polyimide-aluminum composite film is wrapped around a silver-plated copper strip, with a wrapping overlap rate of 50%.

[0026] Silver-plated copper wires are braided onto the polyimide-aluminum composite film to obtain a semi-finished product;

[0027] The semi-finished product is extruded using a sleeve-type high-temperature mold to bond the sheath layer to the semi-finished product, and deep cross-linking is achieved through two-stage vulcanization, wherein the vulcanization temperature is 230℃ and the vulcanization time is 24h.

[0028] The cable is obtained by segmenting and cooling the sheath layer.

[0029] Compared with the prior art, this application has the following advantages and beneficial effects:

[0030] 1. The flexible high-temperature resistant radio frequency high-voltage cable and its preparation method provided in this application form a shielding layer by placing a polyimide aluminum composite film between the silver-plated copper strip braided layer and the silver-plated copper wire braided layer. This creates a rigid-flexible-rigid buffer system. When the cable is subjected to radial compression or bending, the silver-plated copper wire braided layer first bears and disperses the point impact force. Subsequently, the intermediate flexible polyimide aluminum composite film buffers and redistributes the stress, which is then smoothly transferred to the silver-plated copper strip braided layer. This avoids stress concentration and prevents the polyimide aluminum composite film from being directly punctured or fatigued. At the same time, the polyimide aluminum composite film can prevent direct contact wear between the inner and outer silver-plated copper strip braided layers and the silver-plated copper wire braided layer, ensuring that the cable still has good reliability during long-term use.

[0031] 2. The flexible high-temperature resistant radio frequency high-voltage cable and its preparation method provided in this application form a shielding layer by placing a polyimide aluminum composite film between the silver-plated copper strip braided layer and the silver-plated copper wire braided layer. When electromagnetic waves pass through this composite structure, the silver-plated copper wire braided layer and the polyimide aluminum composite film form an impedance abrupt change interface. The electromagnetic waves will undergo multiple reflections and absorptions at this interface, thereby being synergistically attenuated to achieve a good shielding effect. Furthermore, at the physical level, the middle polyimide aluminum composite film physically isolates the inner and outer silver-plated copper strip braided layers and the silver-plated copper wire braided layers, which can prevent the formation of electromagnetic leakage channels and avoid mesh leakage. On the one hand, it can prevent the cable from being interfered with by external factors, and on the other hand, it can prevent the cable's electrical signal from being distorted. In addition, the middle polyimide aluminum composite film also disrupts the formation conditions of the resonant cavity, making the shielding effectiveness more flat and stable throughout the entire frequency band, with no significant weak frequency bands.

[0032] 3. The flexible high-temperature resistant radio frequency high-voltage cable and its preparation method provided in this application form a shielding layer by placing a polyimide aluminum composite film between the silver-plated copper strip braided layer and the silver-plated copper wire braided layer. The silver-plated copper strip braided layer and the silver-plated copper wire braided layer can provide excellent longitudinal heat conduction path, while the polyimide aluminum composite film in the middle can provide good lateral heat diffusion capability. The polyimide aluminum composite film, the silver-plated copper strip braided layer and the silver-plated copper wire braided layer together form a three-dimensional heat dissipation network, which can conduct the heat generated by the inner conductor to the surface of the sheath layer and even the external environment more quickly, greatly improving the cable's resistance to high-temperature environments. At the same time, the polyimide aluminum composite film in the middle completely isolates the silver-plated copper strip braided layer and the silver-plated copper wire braided layer, cutting off the ion path of the electrochemical corrosion micro-cell, ensuring that the cable still has good working capability in harsh environments such as humidity and salt spray, and improving the cable's versatility to a certain extent.

[0033] 4. The flexible high-temperature resistant radio frequency high-voltage cable and its preparation method provided in this application have an inner conductor made of tin-copper alloy monofilaments covered with a nickel layer, which has extremely strong high-temperature stability. This performance is due to the stable phase structure formed by tin, which can suppress grain growth at high temperatures. After continuous operation in a 300℃ environment for 1000 hours, the grain size can still be controlled within 20μm, which is 1 / 3 of that of ordinary copper alloys, and can ensure the stable transmission of high-frequency signals in high-temperature environments.

[0034] 5. The flexible high-temperature resistant radio frequency high voltage cable and its preparation method provided in this application use polyimide film as the insulation layer, which improves the temperature resistance by 20% compared with the commonly used PE / PTFE type radio frequency high voltage cable in the prior art. Under high voltage (above 10KV) environment, the transmission stability can be improved by more than 20%, which greatly improves the signal transmission stability. Attached Figure Description

[0035] To more clearly illustrate the technical solutions of the exemplary embodiments of this application, the accompanying drawings used in the embodiments will be briefly described below. It should be understood that the following drawings only show some embodiments of this application and should not be considered as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort. In the drawings:

[0036] Figure 1 This is a schematic diagram of the flexible high-temperature resistant radio frequency high-voltage cable structure provided in the embodiments of this application;

[0037] Figure 2 This is a schematic diagram of the radial cross-sectional structure of a flexible high-temperature resistant radio frequency high-voltage cable provided in an embodiment of this application.

[0038] The attached diagram shows the markings and corresponding component names:

[0039] 1-Inner conductor, 2-Insulation layer, 3-Shielding layer, 31-Silver-plated copper strip braided layer, 32-Polyimide aluminum composite film, 33-Silver-plated copper wire braided layer, 4-Sheath layer. Detailed Implementation

[0040] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the embodiments and accompanying drawings. The illustrative embodiments and descriptions of this application are only for explaining this application and are not intended to limit this application.

[0041] Firstly, you can refer to this as well. Figure 1 and Figure 2 This application provides a flexible high-temperature resistant radio frequency high-voltage cable, which includes an inner conductor 1, an insulation layer 2, a shielding layer 3, and a sheath layer 4.

[0042] In this embodiment, the inner conductor 1 is configured to be formed by stranding multiple nickel-tin-copper alloy monofilaments. The nickel layer thickness on the nickel-tin-copper alloy monofilament is not less than 3 μm. In actual implementation, the nickel layer thickness on the nickel-tin-copper alloy monofilament can be configured to 3 μm. The mass percentage of tin in the tin-copper alloy monofilament is 7.5%~9%, and the diameter of the tin-copper alloy monofilament is 0.5 mm~4.6 mm. This ensures stable transmission performance at 400°C and guarantees its oxidation resistance temperature reaches 650°C, thereby enabling stable transmission of high-frequency signals at a high temperature of 200°C, providing precise high-frequency microwave signals for the device. In actual implementation, the inner conductor 1 has a multi-layer structure. In the direction extending radially outward from the center, the first layer is a single nickel-tin-copper alloy monofilament, the second layer is six nickel-tin-copper alloy monofilaments, and the third layer is twelve nickel-tin-copper alloy monofilaments. Each layer increases with six nickel-tin-copper alloy monofilaments in sequence. The nickel-tin-copper alloy monofilaments in each layer are regularly twisted to ensure that the outer nickel-tin-copper alloy monofilaments are evenly wrapped around the inner nickel-tin-copper alloy monofilaments.

[0043] In this embodiment, the insulating layer 2 is a polyimide film. The insulating layer 2 is wrapped around the outer side of the inner conductor 1 with a 50% overlap and a thickness of 0.051mm~0.254mm, ensuring a tight bond between the insulating layer 2 and the inner conductor 1. This guarantees excellent electrical performance of the cable; the dielectric constant and dielectric loss are almost unaffected by temperature changes, allowing for the transmission of radio frequency signals at high temperatures. After 1000 hours of thermal aging at 240℃, the mass loss is less than 1.5%, and the increase in dielectric loss is less than 10%, lower than the 5.2% mass loss of ordinary PI film under the same conditions. In actual implementation, the surface of the insulating layer 2 away from the inner conductor 1 has a perfluoroethylene propylene coating. The elastic modulus of the perfluoroethylene propylene coating (2.5GPa) is significantly lower than that of conventional PI substrate (3.5GPa), resulting in a bending radius as low as 0.5mm at 240℃ and a dynamic bending life greater than 500,000 cycles. Through the above technical solutions, the flexible high-temperature resistant radio frequency high-voltage cable provided in this application embodiment has excellent signal transmission stability. By wrapping polyimide film as insulation layer 2, the insulation shrinkage rate is reduced by 15% compared with conventional PE / PTFE type radio frequency high-voltage cable, and the transmission stability can be improved by more than 20%, which greatly improves the signal transmission stability.

[0044] In this embodiment of the application, the shielding layer 3 is a metal composite shielding layer 3, which is wrapped around the outside of the insulating layer 2. The shielding layer 3 includes a silver-plated copper strip braided layer 31, a silver-plated copper wire braided layer 33, and a polyimide aluminum composite film 32, wherein the polyimide aluminum composite film 32 is located between the silver-plated copper strip braided layer 31 and the silver-plated copper wire braided layer 33. Both the silver-plated copper tape braided layer 31 and the silver-plated copper wire braided layer 33 adopt a 2-layer, 2-cross braiding method. The 2-layer refers to the braided layer being composed of two layers of metal wires, which are typically superimposed in opposite twisting directions to improve shielding uniformity and coverage, and reduce electromagnetic interference leakage. The 2-cross refers to the 90-degree cross angle of the metal wires in each braid, a common braiding density standard that provides good mechanical strength and shielding effect. This structure is commonly used for cables with high electromagnetic shielding requirements, such as industrial control cables, communication cables, or high-frequency signal cables. The copper tape width in the silver-plated copper tape braided layer 31 is 0.8mm to 3.5mm, ensuring complete coverage of tiny gaps between layers and providing good shielding performance. Good bending resistance; by setting the polyimide aluminum composite film 32 between the silver-plated copper strip braided layer 31 and the silver-plated copper wire braided layer 33 to form a shielding layer 3, a rigid-flexible-rigid buffer system can be formed. When the cable is subjected to radial compression or bending, the silver-plated copper wire braided layer 33 first bears and disperses the point impact force, and then the intermediate flexible polyimide aluminum composite film 32 buffers and redistributes the stress, and finally smoothly transmits it to the silver-plated copper strip braided layer 31. This can avoid stress concentration and prevent the polyimide aluminum composite film 32 from being directly punctured or fatigued. At the same time, the polyimide aluminum composite film 32 can prevent the inner and outer silver-plated copper strip braided layer 31 and silver-plated copper wire braided layer 33 from direct contact and wear, ensuring that the cable still has good reliability during long-term use. Meanwhile, when electromagnetic waves pass through the composite structure, the silver-plated copper wire braided layer and the polyimide aluminum composite film 32 form an impedance abrupt change interface. The electromagnetic waves will be reflected and absorbed multiple times at this interface, thus being synergistically attenuated to achieve a good shielding effect. Furthermore, at the physical level, the middle polyimide aluminum composite film 32 physically isolates the inner and outer silver-plated copper strip braided layers 31 and silver-plated copper wire braided layers 33, which can prevent the formation of electromagnetic leakage channels and avoid mesh leakage. On the one hand, it can prevent the cable from being interfered with by external factors, and on the other hand, it can prevent the cable's electrical signal from being distorted. In addition, the middle polyimide aluminum composite film 32 also disrupts the formation conditions of the resonant cavity, making the shielding effectiveness more flat and stable throughout the entire frequency band, with no significant weak frequency bands.Furthermore, the silver-plated copper tape braid layer 31 and the silver-plated copper wire braid layer 33 provide excellent longitudinal heat conduction paths, while the polyimide aluminum composite film 32 in the middle provides good lateral heat diffusion capabilities. The polyimide aluminum composite film 32, the silver-plated copper tape braid layer 31, and the silver-plated copper wire braid layer 33 together form a three-dimensional heat dissipation network, which can more quickly conduct the heat generated by the inner conductor 1 to the surface of the sheath layer 4 and even the external environment, greatly improving the cable's resistance to high-temperature environments. At the same time, the polyimide aluminum composite film 32 in the middle completely isolates the silver-plated copper tape braid layer 31 and the silver-plated copper wire braid layer 33, cutting off the ion pathway of the electrochemical corrosion micro-cell, ensuring that the cable still has good working capabilities in harsh environments such as humidity and salt spray, and improving the cable's versatility to a certain extent.

[0045] In this embodiment, the sheath layer 4 is wrapped around the outside of the shielding layer 3. The sheath layer 4 is made of fluororubber and is deeply cross-linked through a vulcanization process, thereby improving the temperature resistance and mechanical properties of the sheath layer 4 itself, and providing better protection for the inner structure of the cable.

[0046] Secondly, this application provides a method for manufacturing a flexible high-temperature resistant radio frequency high-voltage cable, comprising the following:

[0047] S1. Multiple spooled nickel-plated tin-copper alloy monofilaments with diameters of 0.5mm to 4.5mm are loaded into the active wire feeding device of a constant tension horizontal multi-head winding machine. The nickel layer thickness on the surface of the tin-copper alloy should be greater than 3μm. The nickel-plated tin-copper alloy monofilaments are then passed through a servo tension controller, an XYZ three-axis straightener, a nano-coated compression film, and each winding machine head. They are then wound onto a transfer shaft by a tracked pneumatic traction to complete the twisting, forming the inner conductor 1.

[0048] S2. A polyimide film with a width of 8mm to 25mm and a thickness of 0.051mm to 0.254mm, coated with polytetrafluoroethylene propylene, is placed in a wrapping tray and uniformly wound on the outer surface of the inner conductor 1 at a wrapping speed of 160r / min to 200r / min. The overlap rate of the tape is controlled at 50% by a pitch controller to form an insulating layer 2.

[0049] S3. The semi-finished product a from step S2 is fed into a 16-spindle / 24-spindle / 32-spindle metal flat strip braiding machine through a wire feeding device. The machine is wound onto a transfer shaft by an active take-up device. The width of the silver-plated copper strip is 0.8mm to 3.5mm. The strip coverage is controlled to be greater than 90% by a pitch controller. The strip is braided at a uniform speed to ensure that the silver-plated copper strip does not flip or twist during the braiding process, thus completing the wrapping of the silver-plated copper strip braided layer 31.

[0050] S4. Load the semi-finished product b from step S3 into the active wire feeding device of the constant tension vertical single-head wrapping machine, and wrap the polyimide aluminum composite film 32 according to the process of step S2, so that the polyimide aluminum composite film 32 is evenly and tightly covered on the silver-plated copper strip braided layer 31, with a wrapping overlap rate of 50%, and the wrapping of the polyimide aluminum composite film 32 is completed.

[0051] S5. The semi-finished product c from step S4 is processed into silver-plated copper wire using a 16-spindle / 24-spindle / 32-spindle metal braiding machine with a self-unwinding twisting device, thus completing the wrapping of the silver-plated copper wire braid layer 33.

[0052] S6. The semi-finished product d from step S5 is extruded using a sleeve-type high-temperature mold. The elongation coefficient (DRB value 1.05-1.15) is controlled to ensure that the sheath layer 4 and the shielding layer 3 have sufficient and stable adhesion. The extrusion temperature is not lower than 200℃ and can be adjusted according to the wire diameter and speed to avoid melt fracture or bubble generation. Deep cross-linking is achieved through two-stage vulcanization. The vulcanization temperature is 230℃ and the time is 24h. Through the process of activating the bisphenol AF vulcanizing agent at high temperature, the rubber molecules form a three-dimensional network structure, which improves the heat resistance and mechanical properties of the sheath layer 4.

[0053] S7, Segmented Cooling Sheath Layer 4, is cooled by water. The water temperature of each cooling section increases sequentially to prevent internal stress or loosening caused by sudden cooling, and to ensure uniform crystal growth to obtain the finished cable.

[0054] The flexible high-temperature resistant radio frequency high-voltage cable provided in this application embodiment has been tested, and all test indicators meet the expected design. The cable's operating frequency and characteristic impedance are tested using L16 type radio frequency connectors at both ends, employing the time-domain function of a 43.5GHz vector network analyzer. The withstand voltage test is performed using a high-voltage insulation tester. The attenuation test involves placing the cable in a high-temperature chamber; its attenuation performance is significantly lower than that of radio frequency cables of the same size. The main test results are shown in Table 1.

[0055] As shown in Table 1, the test results indicate that the flexible high-temperature resistant radio frequency high-voltage cable provided in this application has better pressure resistance and flexibility than existing cables of the same specification. It also exhibits lower signal attenuation during signal transmission at room temperature and excellent anti-attenuation performance at high temperatures.

[0056] Table 1. Main Performance Indicators of Flexible High-Temperature Resistant Radio Frequency High-Voltage Cables

[0057] The specific embodiments described above illustrate the implementation of this application. Those skilled in the art can easily understand other advantages and effects of this application from the content disclosed in this specification. Although the description of this application is presented in conjunction with some embodiments, this does not mean that the features of this application are limited to this embodiment. On the contrary, the purpose of describing the application in conjunction with embodiments is to cover other options or modifications that may be derived based on the claims of this application. To provide a thorough understanding of this application, many specific details are included in the above description. This application may also be implemented without using these details. Furthermore, to avoid confusion or obscuring the focus of this application, some specific details will be omitted in the description. It should be noted that, unless otherwise specified, the embodiments and features in the embodiments of this application can be combined with each other.

[0058] It should be noted that in this specification, similar reference numerals and letters in the above figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0059] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. A flexible high-temperature resistant radio frequency high-voltage cable, characterized in that, include: Inner conductor (1), the inner conductor (1) is configured to be formed by stranding multiple nickel-tin-copper alloy monofilaments; An insulating layer (2) is wrapped around the outside of the inner conductor (1), wherein the insulating layer (2) is configured as a polyimide film; The shielding layer (3) is wrapped around the outside of the insulating layer (2). The shielding layer (3) includes a silver-plated copper strip braided layer (31), a silver-plated copper wire braided layer (33), and a polyimide aluminum composite film (32). The polyimide aluminum composite film (32) is located between the silver-plated copper strip braided layer (31) and the silver-plated copper wire braided layer (33). Sheath layer (4), which is wrapped around the outside of shielding layer (3).

2. The flexible high-temperature resistant radio frequency high-voltage cable according to claim 1, characterized in that, The diameter of the nickel-tin-copper alloy monofilament is configured to be 0.5 mm to 4.5 mm.

3. The flexible high-temperature resistant radio frequency high-voltage cable according to claim 1, characterized in that, The width of the copper strip in the silver-plated copper strip braided layer (31) is configured to be 0.8 mm to 3.5 mm.

4. The flexible high-temperature resistant radio frequency high-voltage cable according to claim 1, characterized in that, The insulating layer (2) has a fluoroplastic coating on the surface away from the inner conductor (1).

5. The flexible high-temperature resistant radio frequency high-voltage cable according to claim 4, characterized in that, The fluoroplastic coating is a perfluoroethylene propylene layer.

6. The flexible high-temperature resistant radio frequency high-voltage cable according to claim 1, characterized in that, The sheath layer (4) is configured as a fluororubber layer processed by a vulcanization process.

7. The flexible high-temperature resistant radio frequency high-voltage cable according to claim 1, characterized in that, The nickel plating thickness of the surface layer of the nickel-tin-copper alloy monofilament is 3μm.

8. The flexible high-temperature resistant radio frequency high-voltage cable according to claim 1, characterized in that, The thickness of the insulating layer (2) is configured to be 0.051 mm to 0.254 mm.

9. The flexible high-temperature resistant radio frequency high-voltage cable according to claim 8, characterized in that, The insulating layer (2) is configured to be formed by a multi-layer wrapping process, wherein the wrapping overlap is 50%.

10. A method for manufacturing a flexible high-temperature resistant radio frequency high-voltage cable, characterized in that, Includes the following: A stranded nickel-tin-copper alloy wire is used to form the inner conductor (1). An insulating layer (2) is formed by wrapping a polyimide film around the inner conductor (1), wherein the wrapping speed is 160 r / min to 200 r / min and the overlap rate is 50%. Silver-plated copper strip is woven outside the insulation layer (2), wherein the coverage of the silver-plated copper strip is not less than 90%; A polyimide aluminum composite film (32) is wrapped around the silver-plated copper strip, wherein the wrapping overlap rate is 50%. Silver-plated copper wires are braided on the outside of the polyimide aluminum composite film (32) to obtain a semi-finished product; The semi-finished product is extruded using a sleeve-type high-temperature mold to bond the sheath layer (4) to the semi-finished product, and deep cross-linking is achieved through two-stage vulcanization, wherein the vulcanization temperature is 230℃ and the vulcanization time is 24h; The segmented cooling sheath layer (4) is used to obtain the finished cable.

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