A three-phase parallel-axial high temperature superconducting cable

Abstract

The utility model discloses a three -phase parallel axis high temperature superconducting cable in cable field, including flexible support body, three superconducting wire core, outer support pipe, heat insulating layer, shielding layer and protection layer, three superconducting wire core surrounds its outside with flexible support body as center and constitutes cable core, superconducting wire core includes inner support pipe, the inner support pipe outside is provided with superconductive conductor layer, the superconductive conductor layer outside is provided with insulating layer, the inner support pipe inside is first liquid nitrogen channel, the cable core is located the inner support pipe, the clearance between cable core outside and outer support pipe inner wall forms second liquid nitrogen channel, heat insulating layer sets up outside outer support pipe, shielding layer sets up outside heat insulating layer, protection layer sets up outside shielding layer, the utility model discloses can effectively absorb and release thermal stress, protect brittle superconducting tape and insulating layer.

Description

Technical Field

[0001] This utility model belongs to the field of cable technology, and specifically relates to a three-phase parallel axis high-temperature superconducting cable. Background Technology

[0002] High-temperature superconducting (HTS) cables are considered a key technology for future high-capacity, high-efficiency power transmission due to their extremely low resistance loss and potential to carry ultra-high current densities. Superconducting cables typically operate in the liquid nitrogen temperature range (approximately 77K), which presents a significant temperature difference compared to the normal environment. The difference in the thermal shrinkage coefficients of the materials generates significant thermal stress during cooling and operation. Brittle superconducting tapes (such as REBCO or BSCCO tapes) and electrical insulation materials are particularly sensitive to stress accumulation caused by repeated thermal cycling, easily leading to cracking, delamination, or performance degradation. This directly threatens the electrical integrity and service life of the cable, and traditional rigid support structures are ill-suited to effectively absorb and release these stresses. Utility Model Content

[0003] The purpose of this invention is to provide a three-phase parallel-axis high-temperature superconducting cable that effectively absorbs and releases thermal stress, protecting the brittle superconducting tape and insulation layer.

[0004] The purpose of this utility model is achieved as follows: A three-phase parallel-axis high-temperature superconducting cable includes a flexible support body, three superconducting conductor cores, an outer support tube, a heat insulation layer, a shielding layer, and a protective layer. The three superconducting conductor cores are arranged around the flexible support body as the center to form a cable core. Each superconducting conductor core includes an inner support tube. A superconducting conductor layer is disposed on the outside of the inner support tube. An insulation layer is disposed on the outside of the superconducting conductor layer. The inside of the inner support tube is a first liquid nitrogen channel. The cable core is located inside the outer support tube. The gap between the outside of the cable core and the inner wall of the outer support tube forms a second liquid nitrogen channel. The heat insulation layer is disposed on the outside of the outer support tube. The shielding layer is disposed on the outside of the heat insulation layer. The protective layer is disposed on the outside of the shielding layer.

[0005] When this utility model is used, the flexible support body ensures the stability of the basic structure while allowing the cable to undergo certain deformations during thermal expansion and contraction (especially during the process of cooling from room temperature to liquid nitrogen temperature of 77K, as well as temperature fluctuations during operation), thereby effectively absorbing and releasing internal thermal stress and significantly reducing the risk of insulation layer rupture or superconducting tape damage that is prone to occur in rigid connection structures; the inner support tube and the outer support tube provide a robust skeleton support for the superconducting conductor layer, ensuring that the core maintains geometric stability during bending, stretching or cooling. Compared with existing technologies, the advantages of this invention are as follows: the three-phase parallel shaft design makes it easier to control torsional stress during manufacturing, installation, and bending than the traditional stranded design; the flexible support and relatively independent core structure improve the overall flexibility of the cable, facilitating laying, especially for engineering applications requiring long lengths, bends, or complex paths; the first and second liquid nitrogen channels form a "jacketed" cooling structure, ensuring that liquid nitrogen can contact the core from both the inside and outside simultaneously, greatly increasing the cooling surface area and cooling efficiency; and the flexible support and flexible structure design effectively absorb and release thermal stress, protecting the brittle superconducting conductor layer and insulation layer.

[0006] As a further improvement of this utility model, the flexible support body has a third liquid nitrogen channel inside, and the outer periphery is provided with arc-shaped recesses corresponding to the three superconducting wire cores, with a gap between two adjacent superconducting wire cores.

[0007] As a further improvement of this utility model, the flexible support is made of 3J1 elastic alloy material.

[0008] As a further improvement of this utility model, both the outer support tube and the inner support tube are 316L corrugated pipes.

[0009] As a further improvement of this utility model, the insulation layer has a multi-layer structure, which is composed of alternating aluminum foil and low thermal conductivity materials.

[0010] As a further improvement of this utility model, the shielding layer is a copper-nickel alloy shielding layer.

[0011] As a further improvement of this utility model, the protective layer is made of high-density polyethylene material.

[0012] As a further improvement of this utility model, the superconducting conductor layer is formed by wrapping BSCCO tape around the outer periphery of the inner support tube.

[0013] As a further improvement of this utility model, the insulating layer is formed by wrapping polypropylene laminated paper around the outer periphery of the superconducting conductor layer. Attached Figure Description

[0014] Figure 1 This is a three-dimensional structural diagram of the present invention.

[0015] Figure 2 This is a cross-sectional view of the present invention.

[0016] Among them, 1 is a flexible support, 2 is a superconducting conductor core, 201 is an inner support tube, 202 is a superconducting conductor layer, 203 is an insulating layer, 3 is an outer support tube, 4 is a heat insulation layer, 5 is a shielding layer, 6 is a protective layer, 7 is a first liquid nitrogen channel, 8 is a second liquid nitrogen channel, 9 is a third liquid nitrogen channel, and 10 is an arc-shaped recess. Detailed Implementation

[0017] like Figure 1-2 As shown, a three-phase parallel-axis high-temperature superconducting cable includes a flexible support body 1, three superconducting conductor cores 2, an outer support tube 3, a heat insulation layer 4, a shielding layer 5, and a protective layer 6. The three superconducting conductor cores 2 are arranged around the flexible support body 1 to form the cable core. The superconducting conductor core 2 includes an inner support tube 201, a superconducting conductor layer 202 is disposed on the outside of the inner support tube 201, and an insulation layer 203 is disposed on the outside of the superconducting conductor layer 202. The inside of the inner support tube 201 is a first liquid nitrogen channel 7. The cable core is located inside the outer support tube 3. The gap between the outside of the cable core and the inner wall of the outer support tube 3 forms a second liquid nitrogen channel 8. The heat insulation layer 4 is disposed on the outside of the outer support tube 3, the shielding layer 5 is disposed on the outside of the heat insulation layer 4, and the protective layer 6 is disposed on the outside of the shielding layer 5.

[0018] In this embodiment, the flexible support 1 has a third liquid nitrogen channel 9 inside, and the outer periphery is provided with arc-shaped recesses 10 corresponding to the three superconducting wire cores 2, with a gap between adjacent superconducting wire cores 2; in order to ensure that the flexible support 1 maintains extremely high elastic limit, yield strength and toughness flexibility at a liquid nitrogen temperature of 77K, 3J1 elastic alloy material can be used to manufacture the flexible support 1.

[0019] The superconducting conductor layer 202 is formed by wrapping BSCCO (bismuth strontium calcium copper oxide) tape around the outer periphery of the inner support tube 201.

[0020] The insulating layer 203 is formed by wrapping PPLP composite paper (polypropylene laminated paper) around the outer periphery of the superconducting conductor layer 202. Its dielectric properties are better than those at room temperature in a liquid nitrogen environment at -196℃. Its conductivity characteristics are not affected by voltage under DC conditions, and it can stably withstand the high field strength environment of the superconducting cable. The composite structure of porous pulp and polypropylene film gives PPLP high dielectric strength and low-temperature flexibility. The wrapping process can achieve a tight fit with the superconducting conductor layer 202, avoiding interface defects caused by low-temperature shrinkage and its low-temperature adaptability.

[0021] Both the outer support tube 3 and the inner support tube 201 are 316L corrugated pipes. 316L austenitic stainless steel maintains excellent toughness at liquid nitrogen temperature, achieving the dual goals of strong and tough support and thermal stress absorption. The shielding layer 5 is a copper-nickel alloy shielding layer, ensuring efficient magnetic shielding, low loss and short-circuit current carrying capacity, while also having a certain degree of corrosion resistance. The protective layer 6 is made of high-density polyethylene material, which can provide a long-term reliable outer protective layer and shield against environmental damage. The heat insulation layer 4 has a five-layer structure, including three layers of aluminum foil as reflective foil, with a spacer layer made of low thermal conductivity material between adjacent aluminum foil layers.

[0022] The advantages of this utility model are: the arc-shaped recess 10 not only provides a very precise and stable radial positioning for the wire core, but also increases the actual effective contact area between the outer wall of the inner support tube 201 of the wire core and the surface of the flexible support 1. Combined with the good heat conduction effect brought by the third channel, it enhances the "bridge" effect of the support to dissipate heat to the inner surface of the wire core, and significantly reduces the thermal resistance of this path.

[0023] This utility model is not limited to the above embodiments. Based on the technical solutions disclosed in this utility model, those skilled in the art can make some substitutions and modifications to some of the technical features without creative labor, and these substitutions and modifications are all within the protection scope of this utility model.

Claims

1. A three-phase parallel-axis high-temperature superconducting cable, characterized in that, The cable core comprises a flexible support body, three superconducting conductor cores, an outer support tube, a heat insulation layer, a shielding layer, and a protective layer. The three superconducting conductor cores are arranged around the flexible support body to form a cable core. Each superconducting conductor core includes an inner support tube, on the outside of which a superconducting conductor layer is disposed. On the outside of the superconducting conductor layer, an insulating layer is disposed. The interior of the inner support tube is a first liquid nitrogen channel. The cable cores are located inside the outer support tube. The gap between the outer side of the cable cores and the inner wall of the outer support tube forms a second liquid nitrogen channel. The heat insulation layer is disposed on the outside of the outer support tube, the shielding layer is disposed on the outside of the heat insulation layer, and the protective layer is disposed on the outside of the shielding layer.

2. The three-phase parallel-axis high-temperature superconducting cable according to claim 1, characterized in that, The flexible support has a third liquid nitrogen channel inside, and the outer periphery has arc-shaped recesses for the three superconducting wire cores, with a gap between adjacent superconducting wire cores.

3. A three-phase parallel-axis high-temperature superconducting cable according to claim 1, characterized in that, The flexible support is made of 3J1 elastic alloy material.

4. A three-phase parallel-axis high-temperature superconducting cable according to claim 1, characterized in that, Both the outer support pipe and the inner support pipe are 316L corrugated pipes.

5. A three-phase parallel-axis high-temperature superconducting cable according to claim 1, characterized in that, The insulation layer has a multi-layer structure, consisting of alternating aluminum foil and low thermal conductivity materials.

6. A three-phase parallel-axis high-temperature superconducting cable according to claim 1, characterized in that, The shielding layer is a copper-nickel alloy shielding layer.

7. A three-phase parallel-axis high-temperature superconducting cable according to claim 1, characterized in that, The protective layer is made of high-density polyethylene.

8. A three-phase parallel-axis high-temperature superconducting cable according to claim 1, characterized in that, The superconducting conductor layer is formed by wrapping BSCCO tape around the outer periphery of the inner support tube.

9. A three-phase parallel-axis high-temperature superconducting cable according to claim 1, characterized in that, The insulating layer is formed by wrapping polypropylene laminated paper around the outer periphery of the superconducting conductor layer.

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