阅读说明：本技术 一种超导接头衰减补偿装置 (Attenuation compensation device for superconducting joint ) 是由 黄兴 胡新宁 王秋良 崔春艳 王浩 牛飞飞 张子立 张源 于 2020-12-25 设计创作，主要内容包括：本发明涉及一种超导接头衰减补偿装置,包括超导球、超导磁悬浮上线圈、超导磁悬浮下线圈、第一电感和第二电感；所述超导球、所述超导磁悬浮上线圈和所述超导磁悬浮下线圈由上到下依次同轴设置；所述超导磁悬浮上线圈一端与所述第一电感一端连接,所述超导磁悬浮上线圈另一端与所述第一线圈另一端构成超导接头；所述超导磁悬浮下线圈一端与所述第二电感一端连接,所述超导磁悬浮下线圈另一端与所述第二电感另一端构成超导接头。本发明将电感串联进入超导接头的闭环回路中,没有影响主磁场分布,实现了对超导接头电阻带来的电流衰减的补偿效果,超导磁悬浮系统可长期稳定运行。(The invention relates to a superconducting joint attenuation compensation device, which comprises a superconducting ball, a superconducting magnetic suspension upper coil, a superconducting magnetic suspension lower coil, a first inductor and a second inductor, wherein the superconducting ball is arranged on the superconducting magnetic suspension upper coil; the superconducting ball, the superconducting magnetic suspension upper coil and the superconducting magnetic suspension lower coil are coaxially arranged from top to bottom in sequence; one end of the superconducting magnetic suspension upper coil is connected with one end of the first inductor, and the other end of the superconducting magnetic suspension upper coil and the other end of the first coil form a superconducting joint; one end of the superconducting magnetic suspension lower coil is connected with one end of the second inductor, and the other end of the superconducting magnetic suspension lower coil and the other end of the second inductor form a superconducting joint. The invention connects the inductor in series into the closed loop of the superconducting joint, does not influence the distribution of the main magnetic field, realizes the compensation effect of current attenuation brought by the resistance of the superconducting joint, and the superconducting magnetic suspension system can stably operate for a long time.)

1. A superconducting joint attenuation compensation device is characterized by comprising a superconducting ball, a superconducting magnetic suspension upper coil, a superconducting magnetic suspension lower coil, a first inductor and a second inductor;

the superconducting ball, the superconducting magnetic suspension upper coil and the superconducting magnetic suspension lower coil are coaxially arranged from top to bottom in sequence; one end of the superconducting magnetic suspension upper coil is connected with one end of the first inductor, and the other end of the superconducting magnetic suspension upper coil and the other end of the first inductor form a superconducting joint; one end of the superconducting magnetic suspension lower coil is connected with one end of the second inductor, and the other end of the superconducting magnetic suspension lower coil and the other end of the second inductor form a superconducting joint.

2. The superconducting joint attenuation compensation device of claim 1, wherein the second inductor and the first inductor are sequentially arranged on a concentric axis of the upper superconducting magnetic levitation coil and the lower superconducting magnetic levitation coil from top to bottom, and the concentric axis of the second inductor and the concentric axis of the first inductor are perpendicular to the concentric axis of the upper superconducting magnetic levitation coil and the concentric axis of the lower superconducting magnetic levitation coil.

3. A superconducting joint attenuation compensating device according to claim 1 or 2, characterized in that the superconducting magnetically levitated upper coil and the first inductor are made of one superconducting wire, denoted as first superconducting wire; two ends of the first superconducting wire form a superconducting joint; the superconducting magnetic suspension lower coil and the second inductor are made of one superconducting wire and are marked as a second superconducting wire; and two ends of the second superconducting wire form a superconducting joint.

4. The superconducting joint attenuation compensation device of claim 1, wherein the first inductor and the second inductor each comprise a core, an inductor coil, and a shield; the iron core is arranged in the inductance coil, and the inductance coil is arranged in the shielding case.

5. The superconducting joint degradation compensation device of claim 4, wherein the shield material is permalloy.

6. The superconducting joint attenuation compensation device of claim 1, wherein the superconducting joint is made by cold pressure welding.

7. The superconducting joint attenuation compensation device of claim 1, wherein the superconducting ball material is Nb.

8. The apparatus of claim 1, wherein the superconducting magnetic levitation upper coil, the superconducting magnetic levitation lower coil, the first inductor, and the second inductor are made of NbTi/Cu.

Technical Field

The invention relates to the technical field of superconducting magnetic suspension, in particular to a superconducting joint attenuation compensation device.

Background

Superconducting magnetic levitation systems require closed loop applications that are stable for long periods of time. The principle is as follows: the closed loop current in the superconducting suspension upper coil is smaller than the closed loop current in the superconducting suspension lower coil and has a certain proportion relation, so that a gradient magnetic field is formed. According to the Meissner effect, the superconducting Nb balls resist the entering of magnetic flux and interact with the magnetic fields generated by the superconducting suspension upper coil and the superconducting suspension lower coil to generate suspension acting force, so that the superconducting Nb balls are suspended. The suspension force F borne by the superconducting Nb ball and the magnetic induction intensity B at the position of the superconducting Nb ball have the following relationship: KB, F²Where K is a constant, then dF/F is 2 dB/B. The total magnetic induction intensity B generated by the superconducting suspension upper coil and the superconducting suspension lower coil at the superconducting Nb ball is according to the Bio Safael lawIt is known that the suspension force applied to the superconducting Nb sphere is proportional to the square of the closed-loop current I. The superconducting magnetic suspension system requires that the superconducting Nb balls can stably suspend at a certain position with extremely small magnetic field gradient for a long time, and in order to meet the requirements of certain applications, the decay rate of the suspension magnetic field is required to be less than 5 x 10 in one day^-10。

The attenuation rate required by the superconducting magnetic levitation system can be achieved by reducing the resistance of the superconducting joint in the prior art, but the resistance of the superconducting joint can reach 10^-16The Ω level, according to the existing manner of manufacturing superconducting joints, makes it difficult to achieve such a low level of resistance of the superconducting joints.

Disclosure of Invention

The invention aims to provide a superconducting joint attenuation compensation device, which achieves the compensation effect of current attenuation brought by superconducting joint resistance under the condition of not influencing the distribution of a main magnetic field.

In order to achieve the purpose, the invention provides the following scheme:

a superconducting joint attenuation compensation device comprises a superconducting ball, a superconducting magnetic suspension upper coil, a superconducting magnetic suspension lower coil, a first inductor and a second inductor;

the superconducting ball, the superconducting magnetic suspension upper coil and the superconducting magnetic suspension lower coil are coaxially arranged from top to bottom in sequence; one end of the superconducting magnetic suspension upper coil is connected with one end of the first inductor, and the other end of the superconducting magnetic suspension upper coil and the other end of the first inductor form a superconducting joint; one end of the superconducting magnetic suspension lower coil is connected with one end of the second inductor, and the other end of the superconducting magnetic suspension lower coil and the other end of the second inductor form a superconducting joint.

Optionally, the second inductor and the first inductor are sequentially arranged on a concentric axis of the superconducting magnetic levitation upper coil and a concentric axis of the superconducting magnetic levitation lower coil from top to bottom, and the concentric axis of the second inductor and the concentric axis of the first inductor are perpendicular to the concentric axis of the superconducting magnetic levitation upper coil and the concentric axis of the superconducting magnetic levitation lower coil.

Optionally, the superconducting magnetic levitation upper coil and the first inductor are made of one superconducting wire, which is denoted as a first superconducting wire; two ends of the first superconducting wire form a superconducting joint; the superconducting magnetic suspension lower coil and the second inductor are made of one superconducting wire and are marked as a second superconducting wire; and two ends of the second superconducting wire form a superconducting joint.

Optionally, the first inductor and the second inductor each include an iron core, an inductor coil, and a shield; the iron core is arranged in the inductance coil, and the inductance coil is arranged in the shielding case.

Optionally, the shield material is permalloy.

Optionally, the superconducting joint is made by cold pressure welding.

Optionally, the superconducting ball material is Nb.

Optionally, the superconducting magnetic levitation upper coil, the superconducting magnetic levitation lower coil, the first inductor, and the second inductor are made of NbTi/Cu.

According to the specific embodiment provided by the invention, the invention discloses the following technical effects:

the invention discloses a superconducting joint attenuation compensation device, which comprises a superconducting ball, a superconducting magnetic suspension upper coil, a superconducting magnetic suspension lower coil, a first inductor and a second inductor, wherein the superconducting ball is arranged on the superconducting magnetic suspension upper coil; the superconducting ball, the superconducting magnetic suspension upper coil and the superconducting magnetic suspension lower coil are coaxially arranged from top to bottom in sequence; one end of the superconducting magnetic suspension upper coil is connected with one end of the first inductor, and the other end of the superconducting magnetic suspension upper coil and the other end of the first coil form a superconducting joint; one end of the superconducting magnetic suspension lower coil is connected with one end of the second inductor, and the other end of the superconducting magnetic suspension lower coil and the other end of the second inductor form a superconducting joint. The invention connects the inductor in series into the closed loop of the superconducting joint, does not influence the distribution of the main magnetic field, realizes the compensation effect of current attenuation brought by the resistance of the superconducting joint, and the superconducting magnetic suspension system can stably operate for a long time.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.

Fig. 1 is a structural view of a damping compensation apparatus for a superconducting joint according to an embodiment of the present invention;

fig. 2 is a structural diagram of a first inductor or a second inductor according to an embodiment of the present invention;

FIG. 3 is a diagram of a structure of a superconducting magnetic levitation coil provided by an embodiment of the present invention;

fig. 4 is a structural view of a single superconducting wire winding provided in an embodiment of the present invention;

FIG. 5 is a schematic view of the removal of the surface insulating varnish of a NbTi/Cu wire according to an embodiment of the present invention;

FIG. 6 is a structural diagram of an NbTi tube according to an embodiment of the present invention;

fig. 7 is a structural view of a superconducting joint according to an embodiment of the present invention.

Description of the symbols:

1-superconducting ball, 2-superconducting magnetic suspension upper coil, 3-superconducting magnetic suspension lower coil, 4-second inductor, 5-first inductor, 6-superconducting joint, 7-inductor coil, 8-iron core, 9-shielding cover, 10-superconducting joint wire, 11-superconducting wire, 12-NbTi tube,

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The change of the closed loop current in the superconducting suspension upper coil and the superconducting suspension lower coil along with the time is as follows:wherein tau is L/R, L is superconducting magnetic suspension closed loop circuit inductance, and R is superconducting magnetic suspension closed loop circuit superconducting joint resistance. Then at time t after the closed loop current has stabilized₁Current ofTime t₂Current ofBased on the estimated attenuation rate of the current asSince the attenuation rate is inversely related to τ, it is necessary to decrease the attenuation rateThe time constant τ is increased.

Since τ is L/R, there are two ways to increase the time constant τ: and the inductance L of the superconducting magnetic suspension closed loop circuit is improved, or the resistance R of a superconducting joint of the superconducting magnetic suspension closed loop circuit is reduced. If the attenuation rate required by the superconducting magnetic levitation system is achieved by reducing the resistance of the superconducting joint alone, the resistance of the superconducting joint is required to be 10^-16The resistance of the omega level is difficult to reach such a low level according to the existing mode for manufacturing the superconducting joint, so that the attenuation of the resistance of the superconducting joint needs to be compensated by increasing the inductance of a closed loop, and the compensation effect of the current attenuation brought by the resistance of the superconducting joint can be achieved by connecting a sufficiently large inductance in series in the loop.

The invention aims to provide a superconducting joint attenuation compensation device, which achieves the compensation effect of current attenuation brought by superconducting joint resistance under the condition of not influencing the distribution of a main magnetic field.

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in further detail below.

Fig. 1 is a structural diagram of a superconducting joint attenuation compensation apparatus according to an embodiment of the present invention, and as shown in fig. 1, the superconducting joint attenuation compensation apparatus includes a superconducting ball 1, a superconducting magnetic levitation upper coil 2, a superconducting magnetic levitation lower coil 3, a first inductor 5, and a second inductor 4. The superconducting ball 1, the superconducting magnetic suspension upper coil 2 and the superconducting magnetic suspension lower coil 3 are coaxially arranged from top to bottom in sequence. One end of the superconducting magnetic suspension upper coil 2 is connected with one end of the first inductor 5, and the other end of the superconducting magnetic suspension upper coil 2 and the other end of the first inductor 5 form a superconducting joint 6. One end of the superconducting magnetic suspension lower coil 3 is connected with one end of the second inductor 4, and the other end of the superconducting magnetic suspension lower coil 3 and the other end of the second inductor 4 form a superconducting joint 6.

As shown in fig. 1, the second inductor 4 and the first inductor 5 are sequentially arranged on the concentric axis of the superconducting magnetic levitation upper coil 2 and the superconducting magnetic levitation lower coil 3 from top to bottom, and the concentric axis of the second inductor 4 and the first inductor 5 is perpendicular to the concentric axis of the superconducting magnetic levitation upper coil 2 and the superconducting magnetic levitation lower coil 3. The second inductor 4 and the first inductor 5 are strictly perpendicular to the superconducting magnetic levitation upper coil 2 and the superconducting magnetic levitation upper coil 3. The requirements of the superconducting magnetic suspension system on the suspension main magnetic field can be met, and the first inductor 5 and the second inductor 4 cannot influence the distribution of the magnetic suspension main magnetic field.

In the present embodiment, the superconducting magnetically levitated upper coil 2 and the first inductor 5 are made of one superconducting wire, denoted as a first superconducting wire, both ends of which constitute the superconducting joint 6. The superconducting magnetic suspension lower coil 3 and the second inductor 4 are made of one superconducting wire and are marked as a second superconducting wire, and two ends of the second superconducting wire form a superconducting joint 6.

Fig. 2 is a structural diagram of a first inductor or a second inductor according to an embodiment of the present invention, and as shown in fig. 2, each of the first inductor 5 and the second inductor 4 includes an iron core 8, an inductor coil 7, and a shielding cover 9. The core 8 is arranged in the inductor coil 7 and the inductor coil 7 is arranged in the shield 9. The iron core 8 is placed in the inductance coil 7, so that the inductance is large enough, the winding process of the inductance is simplified, and the volume of the inductance is reduced. The inductor coil 7 is arranged in the shielding case 9, so that the interference of the residual magnetism of the iron core 8 on the main magnetic field and the interference of the inductor and the main magnetic field caused by the imperfect vertical arrangement of the inductor and the superconducting magnetic suspension coil can be shielded. Because the remanence of the iron core 8 is a static magnetic field, and the closed loop of the superconducting suspension coil in the superconducting magnetic suspension system uses direct current to generate the static magnetic field, the material of the shielding case 9 is permalloy.

In order to simplify the winding process of the inductor and reduce the volume of the inductor, the manufacturing requirements of the superconducting joint 6 are also strict. The lower the resistance of the superconducting joint 6, the lower the compensation capability requirement for closed loop inductance, and the smaller the required inductance. Therefore, the superconducting joint 6 can be manufactured by adopting a cold pressure welding mode, and the resistance of the superconducting joint 6 reaches 10^-12Of the order of omega.

In the present embodiment, the material of superconducting ball 1 is Nb. The superconducting magnetic suspension upper coil 2, the superconducting magnetic suspension lower coil 3, the first inductor 5 and the second inductor 4 are made of NbTi/Cu materials.

The device realizes the long-term stable operation of the superconducting magnetic suspension system by connecting the inductor into the closed loop of the superconducting joint in series under the condition that the resistance of the superconducting joint is not enough to meet the long-term stable work of the superconducting magnetic suspension system, and overcomes the phenomenon of overhigh closed loop current attenuation caused by the defects of the existing superconducting joint preparation process under the condition that the distribution of a main magnetic field is not influenced.

The device has the following manufacturing process:

the inductance coil 7 is wound by a single superconducting NbTi/Cu wire to a required inductance value. Then, the iron core 8 penetrates into the inductance coil 7, and the inductance coil 7 is wrapped by the shielding cover 9 to form the first inductor 5 and the second inductor 4, so that the magnetic field of the device cannot be influenced by a superconductive suspension main magnetic field after the device is installed. The wound inductor is shown in fig. 2.

After the first inductor 5 and the second inductor 4 are manufactured, the superconducting magnetic suspension upper coil 2 and the superconducting magnetic suspension lower coil 3 are respectively wound by superconducting NbTi/Cu wires for winding the first inductor 5 and the second inductor 4. Then, the superconducting ball 1, the superconducting magnetic suspension upper coil 2, the superconducting magnetic suspension lower coil 3, the second inductor 4 and the first inductor 5 are coaxially arranged from top to bottom. The second inductor 4 and the first inductor 5 are strictly perpendicular to the superconducting magnetic levitation upper coil 2 and the superconducting magnetic levitation upper coil 3. The wound superconducting magnetic levitation coil is shown in fig. 3.

And finally, manufacturing a superconducting joint 6 by using a superconducting NbTi/Cu wire wound with the superconducting magnetic suspension upper coil 2 and the superconducting magnetic suspension lower coil 3. The structure of a single superconducting wire wound is shown in fig. 4.

The manufacturing process of the superconducting joint 6 is as follows:

the insulating paint on the surface of the NbTi/Cu wire is removed by using a paint remover, and then the wire is washed clean by using alcohol.

Mixing sulfuric acid and nitric acid according to the proportion of 1: 3, the joint end of the superconducting joint wire 10 is corroded by the prepared mixed acid solution, when the copper matrix in the NbTi/Cu superconducting wire is completely corroded by the mixed acid solution, the copper matrix is cleaned by alcohol to remove residues, and the NbTi superconducting wire 11 is exposed after drying, as shown in fig. 5.

Soaking the NbTi tube 12 in ethane, washing back and forth for 3 times by using ultrasonic waves, then washing with alcohol and drying, and fig. 6 is a structural diagram of the NbTi tube provided by the embodiment of the present invention.

The NbTi superconducting wire is inserted into the NbTi tube 12, and the superconducting wire loop is closed by cold pressure welding to form the superconducting joint 6, and fig. 7 is a structural diagram of the superconducting joint according to the embodiment of the present invention.

After the steps, the superconducting suspension upper coil 2 and the superconducting suspension lower coil 3 form a superconducting magnetic suspension single closed loop circuit, and a superconducting magnetic suspension system capable of stably running for a long time is formed. Due to the compensation effect of the first inductor 5 and the second inductor 4 on the attenuation of the superconducting joint 6, after a gradient magnetic field is formed by currents with certain magnitude in the superconducting levitation upper coil 2 and the superconducting levitation lower coil 3 in a closed loop mode, the superconducting ball 1 can stably levitate at a desired position for a long time.

The embodiments in the present description are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other.

The principles and embodiments of the present invention have been described herein using specific examples, which are provided only to assist in understanding the core concepts of the present invention; meanwhile, for a person skilled in the art, according to the idea of the present invention, the specific embodiments and the application range may be changed. In view of the above, the present disclosure should not be construed as limiting the invention.