High-temperature-resistant and high-voltage-resistant cable for aerospace and preparation method thereof

Abstract

The invention discloses a high-temperature-resistant and high-voltage-resistant cable for aerospace. The high-temperature-resistant and high-voltage-resistant cable sequentially comprises a conductor core layer, an inner semi-conductive layer, a combined insulating layer, an outer semi-conductive layer and a shielding layer from inside to outside, wherein the combined insulating layer is of a combined structure formed by wrapping a polyimide composite film and extruding polyether-ether-ketone. According to the cable disclosed by the invention, the high temperature resistance, the high pressure resistance and the irradiation resistance are remarkably improved by optimizing the material and the structural design; meanwhile, the device is suitable for a spacecraft high-voltage system, and has the advantages of high reliability, long service life and the like.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of cables, in particular to a high-temperature and high-voltage cable for spacecraft and a preparation method thereof, which is especially suitable for spacecraft systems under high voltage, high load power and complex space environment. BACKGROUND

[0002] During operation of the spacecraft, the cable needs to withstand extreme high temperature, high pressure and strong radiation environment. The traditional high-voltage cable is prone to problems such as high partial discharge, insufficient radiation resistance and the like under high temperature and high pressure environment, resulting in degradation or even failure of the cable performance.

[0003] In the prior art, for example, the patent "Radiation-resistant stable amplitude and phase radio frequency coaxial cable for space flight" with publication number CN116487097A, the cable is composed of an inner conductor, an insulating layer, an outer conductor layer, a stabilizing layer, a shielding layer and a sheath from inside to outside. The insulating layer of the cable is wrapped with a plurality of low-density microporous polytetrafluoroethylene films, and the insulating layer is formed by wrapping with a single material, which is difficult to balance the high-temperature and electrical resistance of the cable.

[0004] At present, although there are some high-temperature resistant cable products, they still have deficiencies in terms of high-temperature resistance, radiation resistance and partial discharge control. For example, the insulating material of some cables is prone to softening and deformation at high temperatures, resulting in a decrease in insulating performance; in a strong radiation environment, the material is prone to degradation, affecting the service life of the cable; at the same time, the problem of partial discharge has always been a key factor that hinders the safe operation of the cable in a high-voltage environment.

[0005] Therefore, there is an urgent need for a new type of cable that can significantly reduce the partial discharge while ensuring high-voltage resistance, and improve the high-temperature and radiation resistance. SUMMARY

[0006] The purpose of the present application is to provide a high-temperature and high-voltage cable for space flight, which solves the problem of poor high-temperature and radiation resistance of cable products in the prior art.

[0007] The purpose of the present application can be achieved by the following technical solutions:

[0008] A high-temperature and high-voltage cable for space flight comprises, from inside to outside, a conductor core layer, an inner semi-conductive layer, a combined insulating layer, an outer semi-conductive layer and a shielding layer.

[0009] The combined insulating layer is a combination of a polyimide composite film wrapping and a polyether ether ketone extrusion structure. The combined insulating layer uses a combination of two materials to make the prepared cable resistant to 260℃ high temperature and excellent in electrical resistance, and the combination of the two materials in the form of wrapping and extrusion can reduce the stress of the cable.

[0010] As a further scheme of the present application: the innermost layer of the combined structure of the combined insulation layer is an inner polyimide composite film layer wrapped around the outer wall of the inner semiconductive layer, the middle layer is a polyether ether ketone layer extruded on the outer wall of the inner polyimide composite film layer, and the outermost layer is an outer polyimide composite film layer wrapped around the outer wall of the polyether ether ketone layer; so that the combined insulation layer can form a gradient insulation structure, thereby having both high-temperature resistance and electrical resistance, while reducing cable stress.

[0011] As a further scheme of the present application: the conductor core layer is a tightly pressed concentric stranded structure of multiple strands of nickel-plated copper wires; the nickel plating is tightly pressed so that the conductor core layer has excellent electrical conductivity and thermal conductivity, corrosion resistance and oxidation resistance, and can withstand 260℃ high temperature for a long time, and the tightly pressed process makes the internal structure of the conductor core layer compact and reduces the gap between the conductors.

[0012] As a further scheme of the present application: the inner semiconductive layer and the outer semiconductive layer are polyimide semiconductive films, which can ensure temperature resistance while homogenizing the electrical field of the conductor.

[0013] As a further scheme of the present application: the shielding layer is a nickel-plated copper wire woven shielding structure, which ensures the high-temperature resistance of the shielding and tightens and protects the cable insulation.

[0014] A preparation method of a high-temperature and high-pressure cable for aerospace, comprising the following steps:

[0015] S1, conductor core layer preparation, tightly pressing and concentrically stranding multiple strands of nickel-plated copper wires;

[0016] S2, inner semiconductive layer coating, coating a polyimide semiconductive film on the surface of the conductor core layer;

[0017] S3, combined insulation layer preparation, wrapping an inner polyimide composite film on the surface of the polyimide semiconductive film, extruding a polyether ether ketone on the surface of the inner polyimide composite film, and finally wrapping an outer polyimide composite film on the surface of the polyether ether ketone;

[0018] S4, outer semiconductive layer and shielding layer coating, sequentially coating a polyimide semiconductive film and a nickel-plated copper wire woven shielding layer on the surface of the combined insulation layer.

[0019] As a further scheme of the present application: the tightly pressed concentric stranding process pressure of the conductor core layer in step S1 is 50-100MPa.

[0020] As a further scheme of the present application: the wrapping thickness of the inner polyimide composite film and the outer polyimide composite film in step S3 is 0.5-1.0mm.

[0021] As a further scheme of the present application: the extrusion thickness of the polyether ether ketone in step S3 is 1.0-1.5 mm.

[0022] As a further scheme of the present application: the diameter of the nickel-plated copper wire of the shielding layer in step S4 is 0.1-0.3 mm.

[0023] The beneficial effects of the present application are:

[0024] (1) The cable prepared in the present application has excellent high-temperature resistance, and the cable can operate stably for a long time at a high temperature of 260℃, and the polyimide composite film and the polyether ether ketone material can still maintain good insulation performance and mechanical performance at high temperature.

[0025] (2) The cable prepared in the present application has good high-voltage resistance, and the combined insulation layer is designed by a special gradient insulation structure and selected by a material, so that the cable can withstand a higher voltage, the partial discharge amount is small, and the safety of the cable in a high-voltage environment is effectively improved.

[0026] (3) The cable prepared in the present application has strong radiation resistance: after being irradiated by a radiation dose of 1×10^6 Gy, the performance of the cable can still remain stable, and can adapt to the characteristics of strong radiation in the aerospace environment.

[0027] (4) The cable prepared in the present application has excellent mechanical properties, the tensile strength of the cable is ≥200 MPa, the bending radius is ≤5 times the diameter of the cable, and the cable has good mechanical properties and can adapt to various mechanical stresses in the installation and use process of the aerospace equipment.

[0028] (5) The cable prepared in the present application significantly improves the high-temperature resistance, high-voltage resistance and radiation resistance by optimizing the conductor structure, using a composite insulation layer and a semi-conductive layer design, and is suitable for complex space environments. BRIEF DESCRIPTION OF DRAWINGS

[0029] The present application will be further described below with reference to the accompanying drawings.

[0030] Figure 1 is a structural schematic diagram of a high-temperature and high-voltage cable for aerospace applications according to the present application.

[0031] In the figure: 10, a conductor core layer; 20, an inner semi-conductive layer; 30, a combined insulation layer; 40, an outer semi-conductive layer; and 50, a shielding layer. DETAILED DESCRIPTION

[0032] With reference to the accompanying drawings, the technical solutions in the embodiments of the present application will be described clearly and completely. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by a person of ordinary skill in the art without creative work fall within the protection scope of the present application.

[0033] In the description of the present application, it should be understood that the orientation description, such as the orientation or position relationship indicated by up, down, front, back, left, right and the like, is based on the orientation or position relationship shown in the drawings, and is only for the purpose of describing the present application / invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation of the present application.

[0034] In the description of the present application, the meaning of several is one or more, and the meaning of multiple is two or more. Greater than, less than, more than and the like are understood as not including the number, and above, below, within and the like are understood as including the number. If the first and the second are described, they are only used for the purpose of distinguishing technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated or the order of the technical features indicated.

[0035] Please refer to Figure 1 As shown in the drawings, the present application is a high-temperature and high-pressure resistant cable for spaceflight, which comprises, from inside to outside, a conductor core layer 10, an inner semi-conductive layer 20, a combined insulation layer 30, an outer semi-conductive layer 40 and a shielding layer 50. The combined insulation layer 30 is a combined structure of a polyimide composite film and a polyether ether ketone extrusion. The combined insulation layer 30 structure is used in the cable of the present application, and the combination of the two materials makes the prepared cable resistant to 260℃ high temperature and excellent in electrical performance. The combination of the two materials in the form of winding and extrusion can reduce the stress effect of the cable.

[0036] In the cable design, the conductor core layer 10 is a tightly pressed concentric stranded structure of multiple strands of nickel-plated copper wire. The nickel plating is tightly pressed to make the conductor core layer 10 have excellent electrical conductivity and thermal conductivity, corrosion resistance and oxidation resistance, and can withstand 260°C high temperature for a long time. At the same time, the tight pressing process makes the internal structure of the conductor core layer 10 compact and reduces the gap between the conductors. The inner semi-conductive layer 20 and the outer semi-conductive layer 40 are polyimide semi-conductive films, which can ensure temperature resistance while homogenizing the conductor electric field. The combined structure of the combined insulation layer 30 has an inner polyimide composite film layer wrapped around the outer wall of the inner semi-conductive layer 20, a polyether ether ketone layer extruded on the outer wall of the inner polyimide composite film layer, and an outer polyimide composite film layer wrapped around the outer wall of the polyether ether ketone layer. The combined insulation layer 30 can form a gradient insulation structure, thereby having both high temperature resistance and electrical performance, while reducing cable stress. The shielding layer 50 is a nickel-plated copper wire woven shielding structure, which ensures the high temperature resistance of the shielding and tightens and protects the cable insulation.

[0037] A method for preparing a high-temperature and high-pressure cable for aerospace, comprising the following steps:

[0038] S1, the conductor core layer 10 is prepared by tightly pressing and concentrically stranding multiple strands of nickel-plated copper wire. The tight pressing and concentric stranding process of the conductor core layer 10 has a pressure of 50-100 MPa. In specific operation, the concentric stranding and tight pressing combined process is used for preparation. The stranding pitch is strictly controlled to be 12±3 times the outer diameter of the conductor core layer 10. The 350°C / 10MPa tight pressing treatment is used to reduce the equivalent diameter by 2.5%. This can effectively reduce the electric field concentration coefficient. By controlling the stranding pitch and tight pressing treatment parameters in this step, the internal structure of the conductor core layer 10 can be made more compact, the electrical conductivity and mechanical strength can be improved, and the internal structure can be made more compact by tight pressing treatment, reducing the gap between the conductors and reducing the contact resistance.

[0039] S2, the inner semi-conductive layer 20 is coated. The polyimide semi-conductive film is coated on the surface of the conductor core layer 10. When the inner semi-conductive layer 20 is prepared, the longitudinal overlap rate of the polyimide semi-conductive film is controlled to be greater than or equal to 15% by controlling the wrapping angle and wrapping tension. The wrapping angle is controlled to be between 30° and 60°, and the wrapping tension fluctuation range is controlled to be within ±5N, so as to ensure the tightness and uniformity of the wrapping layer.

[0040] S3, the combined insulation layer 30 is prepared, the inner polyimide composite film is wrapped around the surface of the polyimide semiconductive film, and the polyether ether ketone is extruded on the surface of the inner polyimide composite film, and finally the outer polyimide composite film is wrapped around the surface of the polyether ether ketone; the thickness of the inner polyimide composite film and the outer polyimide composite film wrapped around is 0.5-1.0 mm, the wrapping operation of the inner polyimide composite film is the same as the operation of the inner semiconductive layer 20 and the outer semiconductive layer 40, the extrusion thickness of the polyether ether ketone is 1.0-1.5 mm, the extrusion temperature is controlled at 380-420 ℃, and the extrusion pressure is controlled at 80-120 MPa; so as to form a gradient insulation structure, the polyimide composite film has excellent insulation performance, high temperature resistance and radiation resistance, and the polyether ether ketone has the advantages of high strength, high rigidity, high temperature resistance, corrosion resistance and the like, and the combination of the two can fully exert the respective advantages and improve the overall performance of the combined insulation layer 30.

[0041] S4, the outer semiconductive layer 40 and the shielding layer 50 are wrapped, and the polyimide semiconductive film and the nickel-plated copper wire braided shielding layer 50 are wrapped on the surface of the combined insulation layer 30 in sequence; similarly, when the outer semiconductive layer 40 is prepared, the longitudinal overlap rate of the polyimide semiconductive film is controlled to be greater than or equal to 15% by controlling the wrapping angle and the wrapping tension, the wrapping angle is controlled to be between 30°-60°, and the wrapping tension fluctuation range is controlled to be within ±5 N, so as to ensure the tightness and uniformity of the wrapped layer; the diameter of the nickel-plated copper wire of the shielding layer 50 is 0.1-0.3 mm, and the shielding layer 50 can be braided by using a 16-spindle braider during preparation, and the braiding angle is 45°±3; the nickel-plated copper wire has good conductivity and corrosion resistance, and the braided structure can effectively shield external electromagnetic interference and also prevent electromagnetic signal leakage in the cable.

[0042] It should be understood that the inner semiconductive layer 20 and the outer semiconductive layer 40 both use polyimide semiconductive film, which has good semiconductive performance and high temperature resistance, and can form a good transition between the conductor core layer 10 and the combined insulation layer 30 and between the combined insulation layer 30 and the shielding layer 50, improve the electric field distribution, and reduce partial discharge.

[0043] The preparation method of the present application is implemented as follows:

[0044] The conductor core layer 10 is prepared, a nickel-plated copper wire with a diameter of 0.5 mm is selected, 19 strands of nickel-plated copper wire are tightly and concentrically stranded, the stranding pitch is controlled to be 12 times the outer diameter of the conductor core layer 10, that is, if the outer diameter of the conductor core layer 10 after stranding is 5 mm, the stranding pitch is 60 mm, and in the stranding process, the tight pressing treatment of 350 ℃ / 10 MPa is simultaneously performed, so that the equivalent diameter is reduced by 2.5%, after the treatment, the conductivity of the conductor core layer 10 is improved, and the internal structure is more compact.

[0045] The inner semiconductive layer 20 is wrapped on the surface of the prepared conductor core layer 10 to wrap a polyimide semiconductive film. The wrapping machine is used for wrapping, the wrapping angle is controlled at 45°, the wrapping tension is controlled at about 10 N, the longitudinal overlap rate of the polyimide semiconductive film is 15%, and the wrapping parameters are accurately controlled to ensure that the inner semiconductive layer 20 uniformly covers the surface of the conductor core layer 10 to form a good transition layer.

[0046] The combined insulation layer 30 is prepared, the inner polyimide composite film is wrapped on the surface of the inner semiconductive layer 20, the wrapping thickness is 0.8 mm, during the wrapping process, the stability of the wrapping machine is maintained to ensure the flatness and thickness uniformity of the wrapping layer; the polyether ether ketone is extruded on the surface of the inner polyimide composite film, the barrel temperature of the extruder is 370℃ in the front section, 380℃ in the middle section and 370℃ in the rear section, the nozzle temperature is 380℃, and the extrusion pressure is controlled at 100 MPa, so that the polyether ether ketone is uniformly extruded and covered on the surface of the inner polyimide composite film, and the extrusion thickness is 1.2 mm; the outer polyimide composite film is wrapped on the surface of the polyether ether ketone, and the wrapping thickness is 0.8 mm. Similarly, the wrapping machine is used for wrapping, the wrapping angle and tension are controlled to ensure that the outer polyimide composite film is uniformly covered.

[0047] The outer semiconductive layer 40 and the shielding layer 50 are wrapped, the polyimide semiconductive film is wrapped on the surface of the combined insulation layer 30, the wrapping angle and tension are controlled to be the same as those of the inner semiconductive layer 20, so that the longitudinal overlap rate is ≥15%; the nickel-plated copper wire braided shielding layer 50 is wrapped, the nickel-plated copper wire with a diameter of 0.2 mm is selected, the 16-spindle braiding machine is used for braiding, the braiding angle is controlled at 45°, and the parameters of the braiding machine are adjusted to ensure that the shielding layer 50 uniformly covers the surface of the outer semiconductive layer 40 to form a good electromagnetic shielding effect.

[0048] In order to verify the performance of the present application, the following tests are carried out:

[0049] High temperature aging test, the prepared cable sample is placed in a high temperature aging box, the temperature is set to 260℃, and the continuous operation is 500 hours, during the aging process, the insulation resistance of the cable is tested regularly, the test results show that after 500 hours of high temperature aging, the insulation resistance of the cable decreases by ≤5%, which indicates that the cable has good insulation performance stability in high temperature environment.

[0050] Radiation resistance performance test, according to IEC60544-2:2012 standard, the radiation resistance performance test of the cable sample is carried out, the sample is exposed to a radiation dose of 1×10^6 Gy, and after the test, the performance indexes such as partial discharge quantity and insulation resistance of the cable are evaluated, the test results show that the partial discharge quantity of the cable is ≤5pC, and the insulation resistance changes little, which indicates that the cable has good radiation resistance performance.

[0051] Mechanical performance test, the tensile strength test is carried out on the cable sample, the test method is carried out according to the relevant standard, and the test result shows that the tensile strength of the cable is greater than or equal to 200 MPa, and the cable can withstand larger mechanical tension; the bending radius test is carried out, and the test result is that the bending radius of the cable is less than or equal to 5 times the diameter of the cable, which shows that the cable has good flexibility and can adapt to various complex installation environments.

[0052] In actual production, the parameters in the above embodiments can be adjusted appropriately according to specific needs and equipment conditions. For example, the number of strands and the diameter of the conductor core layer 10 can be adjusted according to the rated current of the cable; the thickness of each layer in the combined insulation layer 30 can be optimized according to the voltage grade of the cable; the braiding parameters of the shielding layer 50 can be changed according to the strength of electromagnetic interference. At the same time, in the production process, the process parameters should be strictly controlled to ensure the stability of the quality and performance of the cable.

[0053] The above describes one embodiment of the present application in detail, but the content described is only the preferred embodiment of the present application, and cannot be considered as limiting the scope of the present application. Any equivalent changes and improvements made according to the scope of the present application should still belong to the scope of the present application.

Claims

1. A high temperature and high voltage cable for aerospace use, characterized in that: The device comprises, from the inside to the outside, a conductor core layer (10), an inner semiconducting layer (20), a combined insulating layer (30), an outer semiconducting layer (40) and a shielding layer (50); Wherein, the combined insulating layer (30) is a combined structure of polyimide composite film wrapping and polyetheretherketone extrusion.

2. The high temperature and high voltage cable for aerospace use according to claim 1, characterized in that: The innermost layer of the combined structure of the combined insulating layer (30) is an inner polyimide composite film layer wrapped around the outer wall of the inner semi-conductive layer (20), the middle layer is a polyetheretherketone layer extruded on the outer wall of the inner polyimide composite film layer, and the outermost layer is an outer polyimide composite film layer wrapped around the outer wall of the polyetheretherketone layer.

3. The high temperature and high voltage cable for aerospace use according to claim 1, characterized in that: The conductor core layer (10) is a structure of multiple strands of nickel-plated copper wires tightly compressed and coaxially twisted.

4. The high temperature and high voltage cable for aerospace use according to claim 1, characterized in that: The inner semiconductive layer (20) and the outer semiconductive layer (40) are polyimide semiconductive films.

5. The high temperature and high voltage cable for aerospace use according to claim 1, characterized in that: The shielding layer (50) is a nickel-plated copper wire braided shielding structure.

6. A method for preparing a high-temperature and high-voltage cable for aerospace use, characterized in that: The following steps are involved: S1, preparing the conductor core layer (10), pressing and concentrically twisting multiple nickel-plated copper wires into a shape; S2, inner semi-conductive layer (20) coating, coating the surface of the conductor core layer (10) with a polyimide semi-conductive film; S3, preparing a combined insulating layer (30), wrapping an inner polyimide composite film on the surface of the polyimide semiconductive film, extruding polyetheretherketone on the surface of the inner polyimide composite film, and finally wrapping an outer polyimide composite film on the surface of the polyetheretherketone; S4, an outer semiconductive layer (40) and a shielding layer (50) are coated, and a polyimide semiconductive film and a nickel-plated copper wire braided shielding layer (50) are sequentially coated on the surface of the combined insulating layer (30).

7. The method for preparing a high-temperature and high-voltage cable for aerospace use according to claim 6, characterized in that: The pressure of the compacted and coaxially twisted conductor core layer (10) in step S1 is 50-100 MPa.

8. The method for preparing a high-temperature and high-voltage cable for aerospace use according to claim 6, characterized in that: In step S3, the wrapping thickness of the inner polyimide composite film and the outer polyimide composite film are both 0.5-1.0 mm.

9. The method for preparing a high-temperature and high-voltage cable for aerospace use according to claim 6, characterized in that: The extrusion thickness of the polyetheretherketone in step S3 is 1.0 to 1.5 mm.

10. The method for preparing a high-temperature and high-voltage cable for aerospace use according to claim 6, characterized in that: The diameter of the nickel-plated copper wire of the shielding layer (50) in step S4 is 0.1-0.3 mm.

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