Method for winding superconducting conductor and superconducting conductor

Abstract

Embodiments of the present application provide a superconducting conductor winding method and a superconducting conductor. The superconducting conductor winding method includes: inserting a superconducting stacked strip into a superconducting stacked strip groove of a conductor skeleton; after the superconducting stacked strip is inserted, twisting the conductor skeleton to obtain a twisted conductor skeleton; inserting the twisted conductor skeleton into a skeleton channel of a conductor skeleton housing to obtain a superconducting cable, wherein the conductor skeleton housing includes at least one cooling channel; winding and curing the superconducting cable to obtain a superconducting conductor. By twisting the conductor skeleton after the superconducting stacked strip is inserted, the space utilization rate of the conductor is higher, and the engineering current density of the superconducting conductor is further improved. Moreover, by placing the cooling channel in the conductor skeleton housing, the overall cooling effect of the superconducting conductor is improved, and at the same time, the overall current-carrying density of the superconducting conductor can be increased, and the flow resistance can be reduced.

Description

Technical Field

[0001] The embodiments of the present application relate to the field of high-temperature superconducting technology, and particularly to a method for winding a superconducting conductor and a superconducting conductor. Background Art

[0002] High-temperature superconducting tapes have a relatively high upper critical magnetic field strength, a relatively large critical current density, and good mechanical properties. Moreover, due to the limitation of the upper critical magnetic field of low-temperature superconducting tapes, the development of high-temperature superconductivity has attracted much attention. When winding a large high-temperature superconducting coil, in order to reduce the coil inductance and increase the coil stability, high-temperature superconducting tapes are usually connected in parallel, stacked, and welded to form a superconducting stacked cable. The stacking method of the superconducting stack is mainly a stacking and welding method along the tangential direction of the high-temperature superconducting skeleton. For the high-temperature superconducting cable manufactured by this method, with the increase in the number of stacked high-temperature superconducting tapes, a relatively large self-field will be generated. The existence of the self-field seriously affects the current-carrying property and current density of high-temperature superconductivity, and will seriously affect the internal magnetic field distribution of the cable and the safe and stable operation of the cable.

[0003] In a tokamak fusion device, the current change rate of the central solenoid (CS) magnet reaches dozens of kiloamperes per second. In order to reduce the AC loss of the high-temperature superconducting CS magnet, a high-temperature superconducting cable with a transposition structure can be used. Currently, an internal hollow channel can usually be constructed in a circular core skeleton, and a cooling medium flows through the internal hollow channel, which can uniformly cool the magnet. However, if a small-aperture hollow channel is used, the flow resistance of the cable is too large, and the cooling medium can almost only use expensive superfluids; if the aperture of the hollow channel is increased, the strain of the external superconducting tape will increase during torsion and bending, reducing the bending radius of the cable. Summary of the Invention

[0004] In view of this, the embodiments of the present application provide a method for winding a superconducting conductor. One or more embodiments of the present application also relate to a superconducting conductor to solve the technical defects existing in the prior art.

[0005] According to the first aspect of the embodiments of the present application, a method for winding a superconducting conductor is provided, including:

[0006] Inserting a superconducting stacked tape into a superconducting stacked tape slot of a conductor skeleton;

[0007] After the superconducting stacked tape is inserted, twisting the conductor skeleton to obtain a twisted conductor skeleton;

[0008] Inserting the twisted conductor skeleton into a skeleton channel of a conductor skeleton housing to obtain a superconducting cable, wherein the conductor skeleton housing includes at least one cooling channel;

[0009] Winding and curing the superconducting cable to obtain a superconducting conductor.

[0010] According to a second aspect of the embodiments of the present application, a superconducting conductor is provided, including a conductor skeleton and a conductor skeleton housing. The conductor skeleton includes a plurality of superconducting stacked strip grooves, and superconducting stacked strips are inserted into the plurality of superconducting stacked strip grooves. The conductor skeleton housing includes a skeleton channel and at least one cooling channel. The skeleton channel is used to insert the twisted conductor skeleton, and the cooling channel is used to fill a cooling material, and the cooling material is used to cool the superconducting conductor.

[0011] A method for winding a superconducting conductor provided by an embodiment of the present application includes: inserting superconducting stacked strips into the superconducting stacked strip grooves of a conductor skeleton; after the superconducting stacked strips are inserted, twisting the conductor skeleton to obtain a twisted conductor skeleton; inserting the twisted conductor skeleton into the skeleton channel of the conductor skeleton housing to obtain a superconducting cable, wherein the conductor skeleton housing includes at least one cooling channel; winding and curing the superconducting cable to obtain a superconducting conductor. By twisting the conductor skeleton after the superconducting stacked strips are inserted, the space utilization rate of the conductor is higher, and the engineering current density of the superconducting conductor is further improved. Moreover, by placing the cooling channel in the conductor skeleton housing, the overall cooling effect of the superconducting conductor is improved, and at the same time, the overall current-carrying density of the superconducting conductor can be increased, and the flow resistance can be reduced. Description of the Drawings

[0012] Figure 1 is a flowchart of a method for winding a superconducting conductor provided by an embodiment of the present application;

[0013] Figure 2 is a cross-sectional schematic diagram of a conductor skeleton provided by an embodiment of the present application;

[0014] Figure 3 is a structural schematic diagram of a conductor skeleton provided by an embodiment of the present application;

[0015] Figure 4 is a structural schematic diagram of a superconducting stacked strip provided by an embodiment of the present application;

[0016] Figure 5 is a schematic diagram of the simulation result of a twist pitch provided by an embodiment of the present application;

[0017] Figure 6 is a structural schematic diagram of a conductor skeleton housing provided by an embodiment of the present application;

[0018] Figure 7 is a schematic diagram of the simulation result of the flow resistance of cold helium provided by an embodiment of the present application;

[0019] Figure 8 is a schematic diagram of a superconducting cable provided by an embodiment of the present application;

[0020] Figure 9 It is a schematic diagram of the simulation result of the bending radius provided by an embodiment of the present application;

[0021] Figure 10 It is a schematic diagram of the structure of a superconducting conductor provided by an embodiment of the present application;

[0022] Figure 11 It is a schematic diagram of the simulation result of the critical current of a conductor provided by an embodiment of the present application. Specific embodiments

[0023] Many specific details are set forth in the following description in order to provide a thorough understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the connotation of the present application. Therefore, the present application is not limited by the specific embodiments disclosed below.

[0024] The terms used in one or more embodiments of the present application are only for the purpose of describing specific embodiments, and are not intended to limit one or more embodiments of the present application. The singular forms "a", "the", and "said" used in one or more embodiments of the present application and the appended claims are also intended to include the plural forms, unless the context clearly indicates otherwise. It should also be understood that the term "and / or" used in one or more embodiments of the present application refers to and includes any or all possible combinations of one or more of the associated listed items. The term "at least one" in one or more embodiments of the present application refers to "one or more", and "a plurality" refers to "two or more". The term "comprising" is an open description and should be understood as "including but not limited to", and other contents may also be included on the basis of the described contents.

[0025] It should be understood that although the terms first, second, etc. may be used in one or more embodiments of the present application to describe various information, such information should not be limited to these terms. These terms are only used to distinguish the same type of information from each other. For example, without departing from the scope of one or more embodiments of the present application, the first may also be referred to as the second, and similarly, the second may also be referred to as the first. Depending on the context, the word "if" as used herein may be interpreted as "when" or "while" or "in response to a determination".

[0026] First, the noun terms involved in one or more embodiments of the present application are explained.

[0027] Tokamak: When powered on, a huge spiral magnetic field will be generated inside the Tokamak, heating the plasma therein to a very high temperature to achieve the purpose of nuclear fusion.

[0028] Central solenoid: A key component in a tokamak device, mainly used to generate a strong magnetic field, which is crucial for driving plasma current and maintaining plasma stability.

[0029] REBCO (Rare Earth Barium Copper Oxide) superconducting tape: A high-temperature superconducting material based on rare earth barium copper oxide. Here, rare earth elements (RE, Rare Earth) usually include yttrium (Y), gadolinium (Gd), samarium (Sm), europium (Eu), etc., and the most common one is yttrium. Therefore, REBCO sometimes specifically refers to yttrium barium copper oxide. REBCO superconducting tape has high-temperature superconductivity, high critical current density, and good mechanical properties, suitable for various industrial applications.

[0030] Lay length or pitch of twist (LP): A physical quantity measuring the degree of twist, indicating the distance required to complete one full twist on a material of a given length. For example, if a conductor skeleton rotates one full circle (360 degrees) every 1 meter it advances inside the outer shell, then the lay length of this conductor skeleton is 1 meter.

[0031] Torsional strain: Refers to the degree of deformation generated inside an object, such as a wire, cable, or structural member, when it is subjected to torsional force. Torsional strain is an important parameter for measuring how a material deforms under torque and is crucial for evaluating the mechanical properties of materials and designing structures that can withstand specific loads.

[0032] Superconducting conductor: Also known as superconducting material, refers to a superconductor that has both absolute zero resistance and perfect diamagnetism below a certain temperature. After a superconducting conductor completely enters the superconducting state, it will completely expel the external magnetic field from its body, that is, the diamagnetic volume reaches a maximum of 100%, and the diamagnetic susceptibility is -1.

[0033] In this application, a method for winding a superconducting conductor is provided. This application also relates to a superconducting conductor, which will be described in detail one by one in the following embodiments.

[0034] See Figure 1 , Figure 1 shows a flowchart of a method for winding a superconducting conductor provided by an embodiment of this application, specifically including the following steps:

[0035] Step 102: Insert the superconducting stacked tape into the superconducting stacked tape slot of the conductor skeleton.

[0036] It should be noted that a superconducting stacked tape refers to a composite structure composed of multiple layers of superconducting tapes stacked together. The superconducting stacked tape can be a square stacked tape. The superconducting stacked tape has high strength, good superconducting properties, and adaptability to work under strong magnetic fields. The multiple layers of superconducting tapes are stacked in a "stacked" form to enhance the overall current-carrying capacity of the superconducting stacked tape. The superconducting stacked tape can be a high-temperature superconducting material (such as REBCO superconducting tape).

[0037] The conductor skeleton refers to the basic structure used to support and fix the superconducting stacked tape. The conductor skeleton is usually made of non-magnetic materials (such as aluminum alloy, copper, etc.) to avoid interaction with the magnetic field generated by the superconductor. Preferably, due to the advantage of low melting point of the aluminum alloy material, it can be continuously produced by an extrusion process, and the resistance of aluminum is slightly higher than that of copper, resulting in lower eddy current losses inside the conductor. Therefore, the conductor skeleton is preferably made of aluminum alloy.

[0038] The superconducting stacked tape groove refers to a specially designed groove or channel on the conductor skeleton for accommodating and fixing the superconducting stacked tape. The design of the superconducting stacked tape groove takes into account factors such as the size, shape of the superconducting stacked tape, and its thermal expansion after installation. By precisely placing the superconducting stacked tape in the superconducting stacked tape groove, it can ensure uniform current distribution, reduce energy loss, and improve the efficiency and stability of the entire superconducting magnet.

[0039] See Figure 2 , Figure 2 shows a cross-sectional schematic diagram of a conductor skeleton provided by an embodiment of the present application. The number of superconducting stacked tape grooves included in the conductor skeleton can be three, four, five, six, etc., which is specifically selected according to actual situations, and the embodiments of the present application do not make any limitations in this regard.

[0040] In an embodiment of the present application, the conductor skeleton further includes a quench detection channel; before winding and curing the above superconducting cable to obtain a superconducting conductor, the following steps may further be included:

[0041] Insert an optical fiber into the quench detection channel;

[0042] The steps of winding and curing the superconducting cable to obtain a superconducting conductor may include the following steps:

[0043] Wind and cure the superconducting cable with the inserted optical fiber to obtain a superconducting conductor.

[0044] It should be noted that a quench refers to the process in which a superconducting tape changes from its superconducting state to a normal resistance state. This process usually results in a large amount of energy being released in the form of heat. If not detected and processed in a timely manner, it may cause damage to the equipment. Therefore, a quench detection channel can be provided in the conductor skeleton. A quench detection channel refers to a path used to monitor whether a superconducting conductor has quenched. The quench detection channel can be the central aperture of the conductor skeleton. An optical fiber is a slender and flexible medium used for optical signal transmission, usually made of glass or plastic. Due to its excellent temperature sensing ability, electromagnetic interference resistance, long-distance monitoring ability, and flexible installation method, an optical fiber can be used as a quench detection tool.

[0045] Applying the solution of the embodiment of the present application, by inserting an optical fiber into the quench detection channel, the excellent performance of the optical fiber can be utilized to achieve high-precision and rapid monitoring of the state of the superconducting conductor, thereby improving the safety and reliability of the entire superconducting conductor.

[0046] See Figure 3 , Figure 3 Fig. shows a schematic structural diagram of a conductor skeleton provided by an embodiment of the present application. The conductor skeleton includes 5 identical superconducting stacked tape slots and a quench detection channel.

[0047] In an embodiment of the present application, before inserting the superconducting stacked tape into the superconducting stacked tape slot of the conductor skeleton, the superconducting stacked tape can be manufactured. That is, before inserting the superconducting stacked tape into the superconducting stacked tape slot of the conductor skeleton, the following steps can also be included:

[0048] Stack a plurality of superconducting tapes, and cover a metal tape above and below the stack of the stacked superconducting tapes to obtain a superconducting stacked tape.

[0049] It should be noted that the metal tape can protect the stacked superconducting tapes from being damaged when inserted into the superconducting stacked tape slot. Above and below the stack refers to the positions where the stacked superconducting tapes contact the superconducting stacked tape slot. The metal tape can be made of various materials such as thin copper tape, thin stainless steel tape, thin aluminum tape, thin solder tape, etc., and is specifically selected according to the actual situation. The embodiments of the present application do not make any limitations in this regard. If the thickness of the metal tape is too thick, the overall current-carrying density of the superconducting conductor will be reduced. If the thickness of the metal tape is too thin, the purpose of protecting the superconducting tape cannot be achieved. Therefore, two layers of thin metal tapes with the same thickness and width as the superconducting tapes can be covered above and below the stack of the stacked superconducting tapes.

[0050] Applying the solution of the embodiment of the present application, covering a metal tape above and below the stack of the stacked superconducting tapes can protect the stacked superconducting tapes from being damaged when inserted into the superconducting stacked tape slot, making the superconducting conductor more stable.

[0051] In one embodiment of the present application, in addition to using a metal strip to protect the superconducting strip from damage, a solder wire can also be used to fix the superconducting stacked strip from spreading. That is, before inserting the superconducting stacked strip into the superconducting stacked strip groove of the conductor skeleton, the following steps can also be included:

[0052] Wind a solder wire around the outside of the superconducting stacked strip to obtain a fixed superconducting stacked strip;

[0053] Inserting the superconducting stacked strip into the superconducting stacked strip groove of the conductor skeleton may include the following steps:

[0054] Insert the fixed superconducting stacked strip into the superconducting stacked strip groove of the conductor skeleton.

[0055] It should be noted that the solder wire is a metal alloy wire used for electronic soldering, usually composed of tin and other metals (such as lead, silver, copper or bismuth). Since the conductor skeleton will be immersed in liquid solder later, the solder wire can be used to fix the superconducting stacked strip here, and the solder wire will also melt into the liquid solder in the liquid solder.

[0056] Applying the solution of the embodiment of the present application, winding the solder wire tightly around the outside of the superconducting stacked strip can not only ensure that the superconducting stacked strip is not easily scattered during the twisting process, but also ensure that a sufficient amount of solder is provided for the superconducting stacked strip during the subsequent solder impregnation process.

[0057] See Figure 4 , Figure 4 shows a schematic structural diagram of a superconducting stacked strip provided by an embodiment of the present application. Taking any one of the five square superconducting stacked strips as an example, the middle of the superconducting stacked strip is 30 layers of superconducting strips with a width of 3 mm. Two layers of thin copper strips are respectively covered above and below the stack of 30 layers of superconducting strips with a width of 3 mm. Multiple layers of solder wires are tightly wound around the outside of the superconducting stacked strip.

[0058] Step 104: After the superconducting stacked strip is inserted, twist the conductor skeleton to obtain a twisted conductor skeleton.

[0059] It should be noted that the conductor skeleton itself is straight. After inserting the superconducting stacked strip into the superconducting stacked strip groove of the conductor skeleton, after the superconducting strip stacked strip is placed in place, the conductor skeleton inserted with the superconducting stacked strip is twisted as a whole. The superconducting strip stacked strip after twisting is in an inclined state as a whole. The inclined superconducting strip stacked strip not only makes the overall structure of the superconducting cable more compact, but also can cooperate with the internal slip trend of the strip during the subsequent preparation of the superconducting conductor, with higher safety.

[0060] Since the smaller the twist pitch of the superconducting conductor, the lower the AC loss, but twisting will cause damage to the tape due to the twist strain, so the twist pitch cannot be too small. In the embodiments of the present application, in order to determine the minimum twist pitch of the conductor skeleton, a simulation calculation is performed on the conductor, and the calculation results are shown in Figure 5 as follows. Refer to Figure 5 , Figure 5 which shows a schematic diagram of the simulation results of the twist pitch provided by an embodiment of the present application. Figure 5 The model on the left is to first impregnate the superconducting stacked tapes with solder to form a whole, and then place them into the conductor skeleton. The simulation determines that when the twist pitch is 2.2 m, it is close to the critical stress of 700 MPa of the superconducting stacked tapes. Figure 5 The model on the right is that the superconducting stacked tapes are not impregnated with solder to form a whole, and there is slippage between the superconducting stacked tapes. Each superconducting stacked tape is not restricted by adjacent superconducting stacked tapes, and its twist pitch can reach 0.3 m. Therefore, in order to reduce the AC loss of the superconducting conductor and achieve a smaller twist pitch, the superconducting stacked tapes can be kept slidable first, placed into the conductor skeleton and twisted, and then impregnated. At the same time, in order to further protect the superconducting stacked tapes, in practical applications, the twist pitch of the superconducting stacked tapes can be fixed at 0.5 m.

[0061] Step 106: Insert the twisted conductor skeleton into the skeleton channel of the conductor skeleton housing to obtain a superconducting cable, where the conductor skeleton housing includes at least one cooling channel.

[0062] It should be noted that the conductor skeleton housing refers to the external protective layer or structure surrounding the conductor skeleton, which is designed to provide additional mechanical protection and support. The conductor skeleton housing can be square or circular. The conductor skeleton housing contains at least one cooling channel, and the cooling channel is used to conduct the cooling material (which can also be called the cooling medium) to provide a cold source for the superconducting cable, so as to maintain the operating temperature of the superconducting conductor. The cooling materials include but are not limited to liquid nitrogen, liquid helium, cold helium gas, etc., which are specifically selected according to the actual situation, and the embodiments of the present application do not make any limitations in this regard. The skeleton channel refers to a specific channel in the conductor skeleton housing, and the skeleton channel is used to accommodate and fix the twisted conductor skeleton to ensure its correct position and function. After the twisted conductor skeleton is inserted into the skeleton channel of the conductor skeleton housing, the formed assembly is called a superconducting cable. By removing the cooling channel from the conductor skeleton and placing it in the conductor skeleton housing, the overall current-carrying density of the superconducting cable can be improved.

[0063] Refer to Figure 6 , Figure 6The figure shows a schematic structural diagram of a conductor skeleton housing provided by an embodiment of the present application. The conductor skeleton housing is a square housing and includes a circular skeleton channel for placing the conductor skeleton. The conductor skeleton housing further includes a main cooling channel and two sub-cooling channels. The sub-cooling channels are used to assist the main cooling channel in conducting heat for the superconducting stacked tapes on the central conductor skeleton, so as to achieve the low-temperature environment for the normal current flow of the superconducting cable.

[0064] In an embodiment of the present application, the conductor skeleton housing may only include a main cooling channel, or may only include four sub-cooling channels located at the four corners of the conductor skeleton housing. The position and number of the cooling channels in the conductor skeleton housing are specifically selected according to the actual situation, and the embodiments of the present application do not make any limitations in this regard.

[0065] See Figure 7 , Figure 7 The figure shows a schematic diagram of the simulation result of the cold helium gas flow resistance provided by an embodiment of the present application. Through the simulation calculation of Figure 7 , it can be obtained that under the conditions of 20K and 5 bar, a cold helium gas flow rate of 1 g / s can meet the requirements of superconducting cables dozens of meters long. Here, K represents Kelvin, and 5 bar is equal to 500,000 pascals (Pa).

[0066] See Figure 8 , Figure 8 The figure shows a schematic diagram of a superconducting cable provided by an embodiment of the present application. After inserting the twisted conductor skeleton (including superconducting stacked tapes) into the conductor skeleton housing, the structure of the formed superconducting cable can be seen in Figure 8 , and the cross-section utilization rate of the superconducting cable (cross-section of superconducting stacked tapes / total cross-section of superconducting cable) can reach 21.4%.

[0067] In an embodiment of the present application, before inserting the twisted conductor skeleton into the skeleton channel of the conductor skeleton housing to obtain the superconducting cable, the following steps may further be included:

[0068] Immerse the twisted conductor skeleton in liquid solder to obtain an impregnated conductor skeleton;

[0069] Inserting the twisted conductor skeleton into the skeleton channel of the conductor skeleton housing to obtain the superconducting cable may include the following steps:

[0070] Insert the impregnated conductor skeleton into the skeleton channel of the conductor skeleton housing to obtain the superconducting cable.

[0071] It should be noted that the process of immersing the twisted conductor skeleton in liquid solder can be referred to as "solder dipping" or "dip soldering". Before immersing the twisted conductor skeleton in liquid solder, it can be ensured that the twisted conductor skeleton is clean, free of grease, oxides or other contaminants, so as to ensure that the solder can adhere evenly. Then, the solder material can be placed in a suitable container and heated above its melting point to make it liquid. Then, carefully and slowly immerse the twisted conductor skeleton into the liquid solder, and keep it for a certain time to ensure that the solder can fully cover the required area. The dipping speed and depth can be adjusted according to specific application requirements. Finally, take out the twisted conductor skeleton from the liquid solder and let it cool naturally or promote the formation of the solder layer by controlling the cooling rate. During the cooling process, the liquid solder will solidify, forming a uniform solder coating on the surface of the conductor skeleton.

[0072] Applying the solution of the embodiment of the present application, through the method of first twisting and then dipping, the superconducting cable has a smaller twist pitch, thereby reducing the AC loss of the superconducting conductor.

[0073] Step 108: Wind and cure the superconducting cable to obtain a superconducting conductor.

[0074] It should be noted that when winding the superconducting cable, the superconducting cable can be wound into a spiral shape, a ring shape, etc. according to specific application requirements, and cured to obtain a superconducting conductor.

[0075] In practical applications, when winding the superconducting cable, the bending radius is an important parameter in the preparation of the superconducting conductor. In order to obtain the minimum bending radius during the winding of the superconducting conductor, simulation calculations can be performed on the superconducting conductor, and the calculation results are shown in Figure 9 . See Figure 9 , Figure 9 shows a schematic diagram of the simulation result of the bending radius provided by an embodiment of the present application. Figure 9 The superconducting stacked tape model on the left is the whole after solder dipping, without twisting, and it approaches the irreversible stress of the tape when the bending radius (rr, radius of rotation) is 0.35 meters. Figure 9 On the right is the calculation result of the bending strain on the superconducting stacked tape after twisting and bending. The calculation formula is shown in the following formulas (1) to (3):

[0076] (1)

[0077] (2)

[0078] (3)

[0079] Among them, Denotes the strain when there is no impregnation between superconducting stacked tapes and perfect slip; Denotes the strain when there is impregnation between superconducting stacked tapes and no slip, Denotes the bending radius, Denotes the torsional angle per unit length, Denotes the distance in the width direction from the central axis of the superconducting stacked tape, Denotes the distance to the central axis of the superconducting cable, Denotes the torsional angle, Denotes the twist pitch. The minimum bending radius of the superconducting conductor is calculated to be 0.39 m (critical strain 0.004) based on the twist pitch of 0.5 m of the conductor skeleton. In order to further protect the conductor, in practical applications, the bending radius of the superconducting conductor is greater than or equal to the minimum bending radius of 0.39 m, such as it can be set to 0.44 m, Denotes sine, Denotes cosine, Denotes tangent, Is a mathematical constant representing the ratio of the circumference of a circle to its diameter.

[0080] The superconducting conductor wound by the solution of the embodiment of the present application refers to a stacked, twisted, and askew rectangular-shaped conductor. Therefore, the wound superconducting conductor can be called a STAR (Stacked Twisted Askew Rectangular-shaped) conductor, which has a higher space utilization rate, can not only achieve the transposition of superconducting tapes and high current density, but also has a smaller bending radius and smaller flow resistance.

[0081] In an embodiment of the present application, taking the winding shape of the superconducting cable as a spiral shape as an example, the above-mentioned winding and curing of the superconducting cable to obtain a superconducting conductor may include the following steps:

[0082] Spirally layer-wind the superconducting cable to obtain the layer-wound superconducting cable;

[0083] Fill the curing material into the skeleton channel of the layer-wound superconducting cable to obtain the superconducting conductor cured by the curing material.

[0084] It should be noted that spiral winding refers to winding superconducting cables together in a spiral form according to a certain bending radius. Spiral winding helps to optimize the magnetic field distribution and improve the mechanical stability and current-carrying capacity of superconducting conductors. The superconducting cable after winding refers to the superconducting cable after being processed by spiral winding. Since the superconducting cable after winding has been processed by spiral winding, the superconducting cable after winding is a spiral superconducting cable. After completing the winding of the superconducting cable, in order to further enhance the stability of the structure of the superconducting cable after winding and protect the internal superconducting tape from physical damage or other environmental factors, the superconducting cable after winding can be cured. When curing, a curing material can be filled into the skeleton channel of the superconducting cable after winding. The curing material includes but is not limited to epoxy resin, liquid solder, etc., and is specifically selected according to the actual situation, and the embodiments of the present application do not make any limitations in this regard. The superconducting conductor after the curing material is cured refers to that the filled curing material hardens after appropriate treatment (such as heat curing) and forms a solid integral structure with the superconducting cable after winding. At this time, the superconducting conductor has certain mechanical strength, thermal stability and electrical properties, and can be used to construct high-performance superconducting devices, such as magnets or power transmission lines.

[0085] Exemplarily, taking the curing material as liquid solder as an example, after the superconducting cable is spirally wound, the superconducting cable after winding can be heated as a whole, and the melted liquid solder after heating is introduced into the skeleton channel. After the solder is cured, the preparation work of the superconducting conductor can be completed.

[0086] Applying the solution of the embodiments of the present application, by means of first twisting, then bending and winding, and then impregnating, the superconducting tape can be well protected, so that the superconducting conductor has a smaller twist pitch and bending radius, thereby reducing the AC loss of the superconducting conductor and making the superconducting conductor more compact.

[0087] In one embodiment of the present application, after the superconducting cable is spirally wound, adjacent superconducting cable layers may cause current leakage or short-circuit phenomena due to contact. In order to avoid this phenomenon, an insulating material can be covered between adjacent superconducting cables, that is, the superconducting cable after winding includes multiple cable layers; after the above-mentioned spiral winding of the superconducting cable to obtain the superconducting cable after winding, the following steps can also be included:

[0088] Cover an insulating material between adjacent cable layers.

[0089] It should be noted that the insulating material can also be called a dielectric material, which is a type of material that can play a role in preventing current from passing through in electrical equipment. The insulating material includes but is not limited to insulating tapes (such as Teflon tapes, polyimide tapes), epoxy boards, epoxy resin coatings, and is specifically selected according to the actual situation, and the embodiments of the present application do not make any limitations in this regard.

[0090] In practical applications, between adjacent cable layers, the way of covering the insulating material can be selected according to the insulating material. For example, an insulating tape can be pasted on the contact surface between adjacent cable layers, or an epoxy resin coating can be sprayed on the contact surface between adjacent cable layers, or an epoxy board can be placed between adjacent cable layers, etc.

[0091] Applying the solution of the embodiment of the present application, by covering the insulating material between adjacent cable layers, the phenomenon of current leakage or short circuit caused by the contact between adjacent superconducting cable layers is effectively avoided, thereby ensuring the safety and reliability of the superconducting conductor.

[0092] See Figure 10 , Figure 10 shows a schematic structural diagram of a superconducting conductor provided by an embodiment of the present application. The superconducting conductor includes a conductor skeleton and a conductor skeleton housing. The conductor skeleton includes a plurality of superconducting stacked tape slots, and superconducting stacked tapes are inserted into the plurality of superconducting stacked tape slots. The conductor skeleton housing includes a skeleton channel and at least one cooling channel ( Figure 10 there are three in ). The skeleton channel is used to insert the twisted conductor skeleton, and the cooling channel is used to fill the cooling material, and the cooling material is used to cool the superconducting conductor.

[0093] It should be noted that Figure 10 the structural description of the superconducting conductor in is the structural description of a single-layer superconducting conductor, and the structure of each layer of superconducting conductor is the same. The current-carrying capacity of the superconducting conductor is provided by a plurality of superconducting stacked tapes inserted into the superconducting stacked tape slots. The plurality of superconducting stacked tapes are twisted and in an inclined state. The superconducting stacked tape includes a plurality of superconducting tapes stacked together.

[0094] In one embodiment of the present application, thin metal tapes are covered above and below the stack of the stacked superconducting tapes. The thin metal tapes are used to protect the superconducting tapes from being damaged when inserted into the superconducting stacked tape slots.

[0095] In one embodiment of the present application, a soldering wire is also wound around the outside of the superconducting stacked tape. The soldering wire can ensure that the superconducting stacked tape is not easily scattered during the twisting process.

[0096] In one embodiment of the present application, the conductor skeleton further includes a quench detection channel, and an optical fiber for quench detection of the superconducting conductor is inserted into the quench detection channel.

[0097] In one embodiment of the present application, the conductor skeleton housing is square. Setting the conductor skeleton housing to be square can arrange multiple layers of superconducting cables more closely in a limited space. Moreover, the square design can more conveniently fix the superconducting cables and reduce the winding difficulty of the superconducting conductor.

[0098] In one embodiment of the present application, the superconducting conductor includes a plurality of cable layers, and the cooling channel is located between adjacent cable layers.

[0099] It should be noted that the cooling channel located between adjacent cable layers can conduct cooling for two adjacent cable layers simultaneously, so as to quickly reach the low-temperature environment for the superconducting cable to conduct current normally. In one embodiment of the present application, an insulating layer made of an insulating material is further included between adjacent cable layers, and the insulating layer is located between the layers of the superconducting conductor. Exemplarily, the thickness of the conductor skeleton shell can be 15.88 mm, and the thickness of the insulating layer can be 0.12 mm.

[0100] Applying the solution of the embodiment of the present application, since the twisted conductor skeleton is inserted into the skeleton channel of the superconducting conductor, the superconducting conductor has a higher engineering current density. And, since the cooling channel is located inside the conductor skeleton shell, the overall cooling effect of the superconducting conductor is higher, and it has a higher current-carrying density and a lower flow resistance at the same time.

[0101] The above is a schematic solution of a superconducting conductor in this embodiment. It should be noted that the technical solution of this superconducting conductor and the technical solution of the above superconducting conductor winding method belong to the same concept. For the details not described in the technical solution of the superconducting conductor, reference can be made to the description of the technical solution of the above superconducting conductor winding method.

[0102] See Figure 11 , Figure 11 shows a schematic diagram of the simulation result of the critical current of a conductor provided by an embodiment of the present application. The critical current of the superconducting conductor is simulated and calculated under the condition of 77K self-field. The calculation result is shown in Figure 11 , the critical current of a single superconducting tape under 77K self-field is 135 A, and the critical current of the conductor can reach 8.1 kA. Under the conditions of 20K and 8T background field, the critical current of the superconducting conductor calculated can reach 34.4 kA. Therefore, the rated working current of the superconducting conductor can be set to 20.6 kA, and the engineering current density can reach 98 A / mm -2 .

[0103] The above describes a specific embodiment of the present application. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recited in the claims can be performed in a different order than in the embodiments and still achieve the desired result. Additionally, the processes depicted in the figures do not necessarily require the particular order or sequential order shown to achieve the desired result. In certain implementations, multitasking and parallel processing are also possible or may be advantageous.

[0104] It should be noted that, for the foregoing method embodiments, for the sake of simplicity of description, they are all expressed as a series of action combinations. However, those skilled in the art should know that the embodiments of the present application are not limited by the described action sequence, because according to the embodiments of the present application, certain steps can be performed in other sequences or simultaneously. Secondly, those skilled in the art should also know that the embodiments described in the specification are all preferred embodiments, and the actions and modules involved are not necessarily essential for the embodiments of the present application.

[0105] In the above embodiments, the descriptions of the respective embodiments have their own focuses. For the parts not detailed in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0106] The preferred embodiments of the present application disclosed above are only used to help explain the present application. The specification embodiments do not elaborate on all details, nor do they limit the invention to the specific embodiments described. Obviously, according to the content of the embodiments of the present application, many modifications and changes can be made. The present application selects and specifically describes these embodiments to better explain the principles and practical applications of the embodiments of the present application, so that those skilled in the art can well understand and utilize the present application. The present application is only limited by the claims and their full scope and equivalents.

Claims

1. A method for winding a superconducting conductor, characterized in that: include: inserting the superconducting stacked tape into the superconducting stacked tape slot of the conductor skeleton; After the superconducting stacked tape is inserted, twisting the conductor skeleton to obtain a twisted conductor skeleton; Inserting the twisted conductor skeleton into a skeleton channel of a conductor skeleton shell to obtain a superconducting cable, wherein the conductor skeleton shell includes at least one cooling channel and the conductor skeleton is not provided with the cooling channel; Winding and curing the superconducting cable to obtain a superconducting conductor; The step of winding and curing the superconducting cable to obtain a superconducting conductor comprises: spirally winding the superconducting cable to obtain a wound superconducting cable; filling a curing material into a skeleton channel of the wound superconducting cable to obtain the superconducting conductor after the curing material is cured; The layer-wound superconducting cable comprises a plurality of cable layers; after the superconducting cable is spirally layer-wound to obtain the layer-wound superconducting cable, the method further comprises: covering insulating material between adjacent cable layers; Before inserting the twisted conductor skeleton into the skeleton channel of the conductor skeleton shell to obtain the superconducting cable, the method further includes: immersing the twisted conductor skeleton into liquid solder to obtain an immersed conductor skeleton; inserting the twisted conductor skeleton into the skeleton channel of the conductor skeleton shell to obtain the superconducting cable includes: inserting the immersed conductor skeleton into the skeleton channel of the conductor skeleton shell to obtain the superconducting cable; The conductor skeleton also includes a quench detection channel; before the superconducting cable is wound and solidified to obtain the superconducting conductor, it also includes: inserting an optical fiber into the quench detection channel; the superconducting cable is wound and solidified to obtain the superconducting conductor, including: winding and solidifying the superconducting cable with the optical fiber inserted therein to obtain the superconducting conductor.

2. The method according to claim 1, characterized in that Before inserting the superconducting stacked tape into the superconducting stacked tape slot of the conductor skeleton, the method further comprises: A plurality of superconducting tapes are stacked, and metal tapes are covered above and below the stack of the plurality of superconducting tapes to obtain the superconducting stacked tape.

3. The method according to claim 1, characterized in that Before inserting the superconducting stacked tape into the superconducting stacked tape slot of the conductor skeleton, the method further comprises: Winding a solder wire on the outside of the superconducting stacked tape to obtain a fixed superconducting stacked tape; The step of inserting the superconducting stacked tape into the superconducting stacked tape slot of the conductor skeleton comprises: The fixed superconducting stacked tapes are inserted into the superconducting stacked tape slots of the conductor skeleton.

4. A superconducting conductor wound according to the method of any one of claims 1 to 3, characterized in that: It includes a conductor skeleton and a conductor skeleton shell, the conductor skeleton includes a plurality of superconducting stacked tape slots, superconducting stacked tapes are inserted in the plurality of superconducting stacked tape slots, the conductor skeleton shell includes a skeleton channel and at least one cooling channel, the skeleton channel is used to insert the twisted conductor skeleton, the cooling channel is used to fill cooling material, and the cooling material is used to cool the superconducting conductor.

5. The superconducting conductor according to claim 4, characterized in that The superconducting conductor includes a plurality of cable layers, and the cooling channel is located between adjacent cable layers.

6. The superconducting conductor according to claim 4, characterized in that The conductor skeleton shell is square.

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