High-temperature superconducting current lead structure based on helium refrigeration and feed-through coil box body

Abstract

The invention discloses a high-temperature superconducting current lead structure based on helium refrigeration and feeding through a coil box body, and the structure comprises a current lead, the front and rear sides of the current lead are provided with superconducting grooves, one end of the top of the current lead is provided with a helium pipe clamping groove, and a helium pipe is clamped in the helium pipe clamping groove. The current lead superconducting groove is fed through the coil box, and after the superconducting tape and the copper rod are brazed, the sealing performance requirement of the coil box body can be met; after the sealing copper pipe and the current lead indium tin solder are brazed, a sealing effect is achieved; the sealing copper pipe and the sealing stainless steel pipe are brazed through silver-based solder to achieve sealing, the sealing steel pipe and the Dewar link flange are connected through the insulator, the sealing effect is achieved, and the box body can be insulated from the current lead. Through a plurality of sealing structures, the insulation feed-through of the current lead is realized, and the sealed through-flow of the high-temperature superconducting magnet is further realized.

Description

Technical Field

[0001] The present invention belongs to the technical field of superconducting magnets, and specifically relates to a high-temperature superconducting current lead structure based on helium refrigeration and penetrating through a coil box body. Background Art

[0002] Superconducting magnets are an important part of high-temperature superconducting tokamak devices. In order to obtain a higher magnetic field, it is necessary to design magnets with higher currents to maintain the normal operation of the tokamak device. At the same time, higher requirements are also imposed on the current leads to achieve the flow of higher currents without causing additional heat loss. In addition, the coils are often sealed in a box body, and current transmission and penetration are necessary, and insulation from the dewar is also required during current penetration. Currently, there is no current lead on the market that can meet the design requirements. Therefore, there is an urgent need to design a current lead that can achieve the flow of large currents based on helium refrigeration, realize the insulated penetration of the current lead, and then achieve the sealed current flow for high-temperature superconducting magnets. Summary of the Invention

[0003] The purpose of the present invention is to overcome the defects of the prior art and provide a high-temperature superconducting current lead structure based on helium refrigeration and penetrating through a coil box body.

[0004] To achieve the above purpose, the present invention adopts the following technical solutions: A high-temperature superconducting current lead structure based on helium refrigeration and penetrating through a coil box body, including a current lead. Superconducting grooves are opened on both the front and back sides of the current lead. A helium tube slot is opened at one end of the top of the current lead, and a helium tube is clamped in the helium tube slot.

[0005] Preferably, the superconducting groove adopts a square groove structure.

[0006] Preferably, the helium tube slot adopts a U-shaped groove structure, and the helium tube is fixed in the helium tube slot by indium tin soldering.

[0007] Preferably, the helium tube is arranged inside the coil box body. A sealed copper tube is sleeved at the position of the current lead outside the coil box body. A dewar connection flange is sleeved outside the sealed copper tube. On the side of the dewar connection flange close to the coil box body, an insulator and a sealed steel tube are sequentially sleeved.

[0008] Preferably, a number of superconducting tapes are embedded in the superconducting groove. The number of superconducting tapes is arranged vertically, and their outside is limited by a copper tape. The superconducting tapes, the current lead, and the sealed copper tube are impregnated by vacuum soldering to form an integral structure.

[0009] Preferably, the sealed copper tube and the sealed steel tube are sealed and connected by silver-based solder brazing, and the dewar connection flange and the sealed steel tube are connected through an insulator.

[0010] In summary, due to the adoption of the above technical solutions, the beneficial effects of the present invention are as follows: In the present invention, the superconducting slot of the current lead penetrates into the coil box. After the superconducting tape is brazed with the copper bar, the sealing performance requirements of the coil box body can be met; after the sealing copper tube is brazed with the indium tin solder of the current lead, it plays a sealing role; the sealing copper tube and the sealing steel tube are brazed with a silver-based solder to achieve sealing, and the sealing steel tube and the Dewar connection flange are connected through an insulator, which not only realizes the sealing function but also insulates the box body from the current lead; through multiple sealing structures, the insulated penetration of the current lead is realized, and further the sealed current-carrying for the high-temperature superconducting magnet is realized. Description of the Drawings

[0011] Figure 1 is the overall structural schematic diagram of the present invention; Figure 2 is the cross-sectional view of the current lead in the present invention.

[0012] Reference numerals: 1, current lead; 11, superconducting slot; 12, helium tube card slot; 13, helium tube; 2, Dewar connection flange; 3, insulator; 4, sealing steel tube; 5, sealing copper tube. Detailed Description of the Invention

[0013] The following is a detailed description of the specific embodiments of the present invention.

[0014] The "range" disclosed in the present invention is defined in the form of a lower limit and an upper limit. A given range is defined by selecting a lower limit and an upper limit, and the selected lower limit and upper limit define the boundary of a particular range. The ranges defined in this way can include or exclude the end values and can be combined arbitrarily, that is, any lower limit can be combined with any upper limit to form a range. For example, if a range of 10 to 50 is listed for a specific parameter, ranges of 10 to 40 and 20 to 50 are also contemplated. In addition, if the minimum range values 1 and 2 are listed, and if the maximum range values 3, 4, and 5 are listed, the following ranges are all contemplated: 1 to 3, 1 to 4, 1 to 5, 2 to 3, 2 to 4, and 2 to 5. In this application, unless otherwise stated, the numerical range "a to b" represents an abbreviated representation of any real number combination between a and b, where a and b are both real numbers. For example, the numerical range "0 to 5" means that all real numbers between "0 to 5" have been fully listed herein, and "0 to 5" is only an abbreviated representation of these numerical combinations.

[0015] If there is no special description, all embodiments and optional embodiments of the present application can be combined with each other to form a new technical solution.

[0016] If there is no special description, all technical features and optional technical features of the present application can be combined with each other to form a new technical solution.

[0017] Unless otherwise specified, all steps of this application can be carried out sequentially or randomly, preferably sequentially. For example, when the method includes steps (a) and (b), it means that the method may include steps (a) and (b) carried out sequentially, or may include steps (b) and (a) carried out sequentially. For example, when it is mentioned that the method may further include step (c), it means that step (c) can be added to the method in any order. For example, the method may include steps (a), (b) and (c), or may include steps (a), (c) and (b), or may include steps (c), (a) and (b), etc.

[0018] Unless otherwise specified, the "comprising" and "including" mentioned in this application mean open-ended, and can also be closed-ended. For example, the "comprising" and "including" can mean that other components not listed may also be included or contained, or may only include or contain the listed components.

[0019] Unless otherwise specified, the reaction is carried out under normal temperature and normal pressure conditions.

[0020] Unless otherwise specified, all parts or percentages are by weight or weight percentage.

[0021] In the present invention, the substances used are all known substances, which can be purchased or synthesized by known methods.

[0022] In the present invention, the devices or equipment used are all conventional devices or equipment known in the art and can all be purchased.

[0023] The following further illustrates the specific implementation manners of the high-temperature superconducting current lead structure based on helium refrigeration and penetrating the coil casing of the present invention in conjunction with embodiments. The high-temperature superconducting current lead structure based on helium refrigeration and penetrating the coil casing of the present invention is not limited to the descriptions of the following embodiments.

[0024] Example 1: The high-temperature superconducting current lead structure based on helium refrigeration and penetrating the coil casing, as Figure 1-2 shown, includes a current lead 1. Superconducting grooves 11 are opened on both the front and rear sides of the current lead 1. A helium tube slot 12 is opened at one end of the top of the current lead 1, and a helium tube 13 is clamped in the helium tube slot 12.

[0025] In a possible implementation manner, the superconducting groove 11 adopts a square groove structure with a width of 4.5 mm and a depth of 7 mm.

[0026] In a possible implementation manner, the helium tube slot 12 adopts a U-shaped groove structure. The helium tube 13 is a copper tube with a diameter of 1 mm and a length of 6 mm, and the helium tube 13 is fixed in the helium tube slot 12 by indium-tin soldering.

[0027] In a possible implementation, the helium tube 13 is disposed inside the coil box body, and a sealed copper tube 5 is sleeved at a position outside the coil box body on the current lead 1. A Dewar connection flange 2 is sleeved outside the sealed copper tube 5. An insulator 3 and a sealed steel tube 4 are sequentially sleeved on one side of the Dewar connection flange 2 close to the coil box body.

[0028] In a possible implementation, 120 superconducting tapes are embedded in the superconducting slot 11. The 120 superconducting tapes are arranged vertically, and are limited by a copper tape with a thickness of 0.1 mm on the outside. The superconducting tapes, the current lead 1 and the sealed copper tube 5 are impregnated by vacuum soldering to form an integral structure.

[0029] In a possible implementation, the sealed copper tube 5 and the sealed steel tube 4 are hermetically connected by silver-based solder brazing, and the Dewar connection flange 2 and the sealed steel tube 4 are connected by the insulator 3.

[0030] In a possible implementation, as Figure 2 shown, the current lead 1 is processed from a solid copper rod with a diameter of 20 mm (material TU1). Three grooves are processed on its cross-section: two square grooves with a width of 4.5 mm and a depth of 7 mm, and a U-shaped groove for embedding the cold helium tube; the area is divided as Figure 2 shown. The helium tube 13 is a copper tube with a diameter of 6×1 mm and is brazed in the current lead groove by indium-tin brazing. Two square grooves of the current lead 1 are embedded with 120 superconducting tapes (the tapes are arranged vertically, and the outermost side of the groove is limited by a copper tape with a thickness of 0.1 mm), and the vacuum soldering impregnation method is used to impregnate the tapes, the copper rod and the copper tube into an integral structure. The current lead 1 can achieve a current-carrying capacity greater than 100 kA@10K under a 2T background magnetic field, and the operating resistance is less than 3 nΩ.

[0031] In a possible implementation, for the detailed structure of the current lead feedthrough, see Appendix Figure 1 , this structure consists of the current lead 1, the helium tube 13, the sealed copper tube 5, the sealed steel tube 4, the insulator 3, and the Dewar connection flange 2; the left side is the inner side of the coil box body, and the right side is the outer side of the coil box body. The helium tube 13 is made of TU1 and is embedded in the helium tube card slot 12. The helium tube card slot 12 is a U-shaped structure and ends at the front end of the Dewar connection flange 2 with a distance of 20 mm; the superconducting slot 11 of the current lead 1 penetrates into the coil box. After the superconducting tape and the copper rod are brazed, the sealing performance requirements of the coil box body can be met; after the sealed copper tube 5 and the current lead 1 are brazed with indium-tin solder, it plays a sealing role; the sealed copper tube 5 and the sealed steel tube 4 are brazed with silver-based solder to achieve sealing, and the sealed steel tube 4 and the Dewar connection flange 2 are connected by the insulator 3, which not only realizes the sealing function, but also insulates the box body from the current lead 1; the above multi-channel sealing can meet a leakage rate less than 10 -9 Pa·m 3 / s.

[0032] The above content is a further detailed description of the present invention in combination with specific preferred embodiments. It cannot be determined that the specific implementation of the present invention is only limited to these descriptions. For those of ordinary skill in the technical field to which the present invention pertains, without departing from the concept of the present invention, several simple deductions or substitutions can still be made, and all should be regarded as belonging to the protection scope of the present invention.

Claims

1. A high-temperature superconducting current lead structure based on helium refrigeration and penetrating through a coil casing, characterized in that: It includes a current lead (1), superconducting grooves (11) are formed on both the front and back sides of the current lead (1), a helium tube clamping groove (12) is formed at one end of the top of the current lead (1), and a helium tube (13) is clamped in the helium tube clamping groove (12).

2. The high-temperature superconducting current lead structure based on helium refrigeration and penetrating the coil housing according to claim 1, characterized in that: The superconducting groove (11) adopts a square groove structure.

3. The high-temperature superconducting current lead structure based on helium refrigeration and penetrating the coil housing as described in claim 1, characterized in that: The helium tube clamping groove (12) adopts a U-shaped groove structure, and the helium tube (13) is fixed in the helium tube clamping groove (12) by indium-tin soldering.

4. The high-temperature superconducting current lead structure based on helium refrigeration and penetrating the coil housing according to claim 1, characterized in that: The helium tube (13) is arranged inside the coil box body, a sealing copper tube (5) is sleeved at the position of the current lead (1) outside the coil box body, a Dewar connection flange (2) is sleeved outside the sealing copper tube (5), and an insulator (3) and a sealing steel pipe (4) are sequentially sleeved on the side of the Dewar connection flange (2) close to the coil box body.

5. The high-temperature superconducting current lead structure based on helium refrigeration and penetrating through the coil casing according to claim 4, characterized in that: A number of superconducting tapes are embedded in the superconducting groove (11), and the number of superconducting tapes are arranged vertically, and their outer sides are limited by copper tapes. The superconducting tapes, the current lead (1) and the sealing copper tube (5) are impregnated by vacuum soldering to form an integral structure.

6. The high-temperature superconducting current lead structure based on helium refrigeration and penetrating through the coil housing according to claim 4, characterized in that: The sealing copper tube (5) and the sealing steel pipe (4) are hermetically connected by silver-based solder brazing, and the Dewar connection flange (2) is connected to the sealing steel pipe (4) through the insulator (3).

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