阅读说明：本技术 高温超导无绝缘磁体 (High-temperature superconducting uninsulated magnet ) 是由 胡道宇 翟茂春 毛凯 张艳清 吕民东 周伟 龚珺 刘坤 邹玲 朱然 于 2019-04-24 设计创作，主要内容包括：本发明涉及超导磁体技术领域,公开了一种高温超导无绝缘磁体。该磁体包括真空保护壳体和设置在所述真空保护壳体中的多个超导线圈组,每个超导线圈组包括电机、第一切换装置、第二切换装置、热锚、制冷机、储冷罐、多个磁通泵、串联的多个无绝缘超导线圈、恒流开关和冷屏。由此,通过真空层和冷屏可以降低磁体的热辐射,通过采用无绝缘超导线圈可以提高磁体系统稳定性与鲁棒性,并且制冷机对所述冷屏、所述多个无绝缘超导线圈和所述制冷介质进行制冷的混合制冷模式可以确保制冷的可靠性。(The invention relates to the technical field of superconducting magnets and discloses a high-temperature superconducting uninsulated magnet. The magnet comprises a vacuum protection shell and a plurality of superconducting coil groups arranged in the vacuum protection shell, wherein each superconducting coil group comprises a motor, a first switching device, a second switching device, a heat anchor, a refrigerator, a cold storage tank, a plurality of flux pumps, a plurality of non-insulated superconducting coils connected in series, a constant current switch and a cold shield. Therefore, the heat radiation of the magnet can be reduced through the vacuum layer and the cold screen, the stability and robustness of the magnet system can be improved through the adoption of the uninsulated superconducting coil, and the refrigeration reliability can be ensured through the mixed refrigeration mode of refrigerating the cold screen, the plurality of uninsulated superconducting coils and the refrigeration medium by the refrigerator.)

1. A high-temperature superconducting uninsulated magnet is characterized by comprising a vacuum protection shell and a plurality of superconducting coil groups arranged in the vacuum protection shell, wherein each superconducting coil group comprises a motor (3), a first switching device (4), a second switching device (17), a heat anchor (5), a refrigerator, a cold storage tank (6), a plurality of flux pumps (7), a plurality of uninsulated superconducting coils (8) connected in series, a constant current switch (10) and a cold screen (15),

the motor (3) is used for controlling the first switching device (4) to switch between connection and disconnection of an excitation loop, the motor (3) is used for controlling the second switching device (17) to switch between connection and disconnection of a magnetic flux pump loop, current leads of the excitation loop and the magnetic flux pump loop are wound on the heat anchor (5), a magnetic flux pump (7) is arranged on each magnetic flux pump loop, and a constant current switch (10) is arranged on each uninsulated superconducting coil (8);

The cold screen (15) is arranged outside the cold storage tank (6), a refrigerating medium is stored in the cold storage tank (6), the plurality of uninsulated superconducting coils (8) are arranged in the cold storage tank (6), and the refrigerating machine refrigerates the cold screen (15), the plurality of uninsulated superconducting coils (8) and the refrigerating medium.

2. Magnet according to claim 1, characterized in that the vacuum-protected enclosure comprises an outer dewar shell (13), an inner dewar shell (14), and a vacuum layer (1) arranged between the outer dewar shell (13) and the inner dewar shell (14).

3. Magnet according to claim 2, characterized in that the refrigerator comprises a primary cold head (2), a secondary cold head (11) and a cold-conducting fin (18), the primary cold head (2) refrigerating the cold shield (15), the secondary cold head (11) refrigerating the plurality of uninsulated superconducting coils (8) and the refrigerating medium through the cold-conducting fin (18).

4. A magnet as claimed in claim 3, wherein each superconducting coil assembly further comprises a high temperature superconducting lead (12) provided on the excitation loop.

5. Magnet according to claim 5, characterized in that each superconducting coil set further comprises a plurality of supports (9) for fixedly supporting the uninsulated superconducting coils (8).

6. Magnet according to claim 5, characterized in that it further comprises a shielding layer (16) arranged on the vacuum-protected housing.

7. Magnet according to claim 6, characterized in that the material of the shielding layer (16) is metal.

8. Magnet according to claim 1, characterized in that it further comprises detection means, provided on the surface of each uninsulated superconducting coil (8), for detecting the relevant condition parameter of the uninsulated superconducting coil (8).

9. The magnet according to claim 8, wherein the detection means comprises at least one of: temperature detection device, stress detection device, magnetic field detection device and current detection device.

10. Magnet according to any of claims 1-9, characterized in that the first switching means (4) and the second switching means (17) are both sockets.

Technical Field

The invention relates to the technical field of superconducting magnets, in particular to a high-temperature superconducting uninsulated magnet.

Background

High temperature superconducting materials thus have excellent electromagnetic and mechanical properties, and along with the reduction of manufacturing costs thereof, research on high temperature superconducting magnets based on high temperature superconducting materials is becoming more and more extensive. The current applications of high temperature superconducting magnets are mostly focused on static magnets, such as medical MRI magnets and high field magnets. However, when the high-temperature superconducting magnet is applied to a dynamic field, such as a rotor magnet of a superconducting linear motor (for example, a superconducting magnet carried by a japanese sorb line superconducting maglev train, which maintains a speed per hour of the world highest rail transit 603km), a superconducting electrically suspended levitation magnet (for example, a levitation magnet carried by a united states Holloman maglev rocket sled, which has a highest running speed of more than 1000km/h and provides an important test means for high-speed ground test), and the like, the high-temperature superconducting magnet faces a complex electromagnetic and load environment, and the improvement of the stability of the magnet and the prevention of quenching of the magnet are very critical.

Disclosure of Invention

The invention provides a high-temperature superconducting uninsulated magnet, which can solve the technical problems of poor stability and safety in a high-temperature superconducting magnet dynamic environment in the prior art.

The invention provides a high-temperature superconducting uninsulated magnet, wherein the magnet comprises a vacuum protection shell and a plurality of superconducting coil groups arranged in the vacuum protection shell, each superconducting coil group comprises a motor, a first switching device, a second switching device, a heat anchor, a refrigerator, a cold storage tank, a plurality of flux pumps, a plurality of uninsulated superconducting coils connected in series, a constant current switch and a cold shield, wherein,

the motor controls the first switching device to switch between the connection and disconnection of an excitation loop, the motor controls the second switching device to switch between the connection and disconnection of a magnetic flux pump loop, current leads of the excitation loop and the magnetic flux pump loop are wound on the heat anchor, a magnetic flux pump is arranged on each magnetic flux pump loop, and each uninsulated superconducting coil is provided with the constant current switch;

the cold screen is arranged outside the cold storage tank, a refrigerating medium is stored in the cold storage tank, the plurality of uninsulated superconducting coils are arranged in the cold storage tank, and the refrigerating machine refrigerates the cold screen, the plurality of uninsulated superconducting coils and the refrigerating medium.

Preferably, the vacuum protection enclosure comprises an outer dewar shell, an inner dewar shell, and a vacuum layer disposed between the outer dewar shell and the inner dewar shell.

Preferably, the refrigerator includes a primary cold head, a secondary cold head, and a cold conducting sheet, the primary cold head refrigerates the cold shield, and the secondary cold head refrigerates the plurality of uninsulated superconducting coils and the refrigeration medium through the cold conducting sheet.

Preferably, each superconducting coil assembly further comprises a high-temperature superconducting lead wire arranged on the excitation loop.

Preferably, each superconducting coil assembly further includes a plurality of supports for fixedly supporting the uninsulated superconducting coils.

Preferably, the magnet further comprises a shielding layer disposed on the vacuum protection housing.

Preferably, the material of the shielding layer is metal.

Preferably, the magnet further comprises a detection device arranged on the surface of each uninsulated superconducting coil and used for detecting relevant state parameters of the uninsulated superconducting coil.

Preferably, the detection means comprises at least one of: temperature detection device, stress detection device, magnetic field detection device and current detection device.

Preferably, the first switching device and the second switching device are both sockets.

Through the technical scheme, a plurality of superconducting coil groups are arranged in the vacuum protection shell, and each superconducting coil group can comprise a motor, a first switching device, a second switching device, a heat anchor, a refrigerator, a cold storage tank, a plurality of flux pumps, a plurality of non-insulated superconducting coils connected in series, a constant current switch and a cold shield. Therefore, the heat radiation of the magnet can be reduced through the vacuum layer and the cold screen, the stability and robustness of the magnet system can be improved through the adoption of the uninsulated superconducting coil, and the refrigeration reliability can be ensured through the mixed refrigeration mode of refrigerating the cold screen, the plurality of uninsulated superconducting coils and the refrigeration medium by the refrigerator.

Drawings

The accompanying drawings, which are included to provide a further understanding of the embodiments of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention. It is obvious that the drawings in the following description are only some embodiments of the invention, and that for a person skilled in the art, other drawings can be derived from them without inventive effort.

FIG. 1 is a schematic diagram of a high temperature superconducting uninsulated magnet according to an embodiment of the present invention;

Fig. 2 is a schematic diagram showing the arrangement of the shielding layer of the high-temperature superconducting uninsulated magnet according to the embodiment of the invention.

Detailed Description

It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict. 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. The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the invention, its application, or uses. 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.

It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments according to the present application. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, and it should be understood that when the terms "comprises" and/or "comprising" are used in this specification, they specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof, unless the context clearly indicates otherwise.

The relative arrangement of the components and steps, the numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present invention unless specifically stated otherwise. Meanwhile, it should be understood that the sizes of the respective portions shown in the drawings are not drawn in an actual proportional relationship for the convenience of description. Techniques, methods, and apparatus known to those of ordinary skill in the relevant art may not be discussed in detail but are intended to be part of the specification where appropriate. In all examples shown and discussed herein, any particular value should be construed as merely illustrative, and not limiting. Thus, other examples of the exemplary embodiments may have different values. It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, further discussion thereof is not required in subsequent figures.

Fig. 1 is a schematic structural diagram of a high-temperature superconducting uninsulated magnet according to an embodiment of the present invention.

The high-temperature superconducting uninsulated magnet provided by the embodiment of the invention can be applied to the fields of superconducting magnetic levitation trains, magnetic levitation rocket sledges, electromagnetic ejection, magnetic levitation aerospace boosting launching and the like.

As shown in fig. 1, an embodiment of the present invention provides a high-temperature superconducting uninsulated magnet, wherein the magnet includes a vacuum protection housing and a plurality of superconducting coil sets disposed in the vacuum protection housing, each superconducting coil set includes a motor 3, a first switching device 4, a second switching device 17, a heat anchor 5, a refrigerator, a cold storage tank 6, a plurality of flux pumps 7, a plurality of uninsulated superconducting coils 8 connected in series, a constant current switch 10, and a cold shield 15, wherein,

the motor 3 is used for controlling the first switching device 4 to switch between connection and disconnection of an excitation loop, the motor 3 is used for controlling the second switching device 17 to switch between connection and disconnection of a flux pump loop, current leads of the excitation loop and the flux pump loop are wound on the heat anchor 5, a flux pump 7 is arranged on each flux pump loop, and a constant current switch 10 is arranged on each uninsulated superconducting coil 8;

that is, the on-off of the excitation loop and the flux pump loop can be controlled by the motor, and the flux pump can supplement magnetism for the superconducting magnet in real time.

For example, when the superconducting magnet is in operation, the current reduces the magnetic field attenuation, and the magnetic flux pump supplements magnetism to the superconducting magnet in real time to realize the time stability of the magnetic field of the superconducting magnet. Wherein, each uninsulated superconducting coil can be independently provided with a flux pump. For example, the flux pump is a transformer type flux pump, and inputs current 1-2A.

Further, the field circuit and flux pump circuit current leads may be wrapped around the heat anchor multiple times in sufficient contact to reduce heat leakage from the field circuit and flux pump circuit current leads. For example, the excitation loop current lead may be a pluggable excitation current lead and the flux pump loop current lead may be a pluggable flux pump current lead.

The cold screen 15 is arranged outside the cold storage tank 6, a refrigerating medium is stored in the cold storage tank 6, the plurality of uninsulated superconducting coils 8 are arranged in the cold storage tank 6, and the refrigerating machine refrigerates the cold screen 15, the plurality of uninsulated superconducting coils 8 and the refrigerating medium.

For example, the illustrated heat storage tank 6 may be a nitrogen fixation tank in which a plurality of uninsulated superconducting coils 8 are disposed, and the refrigerant medium is nitrogen fixation.

Through the technical scheme, a plurality of superconducting coil groups are arranged in the vacuum protection shell, and each superconducting coil group can comprise a motor, a first switching device, a second switching device, a heat anchor, a refrigerator, a cold storage tank, a plurality of flux pumps, a plurality of non-insulated superconducting coils connected in series, a constant current switch and a cold shield. Therefore, the heat radiation of the magnet can be reduced through the vacuum layer and the cold screen, the stability and robustness of the magnet system can be improved through the adoption of the uninsulated superconducting coil, and the refrigeration reliability can be ensured through the mixed refrigeration mode of refrigerating the cold screen, the plurality of uninsulated superconducting coils and the refrigeration medium by the refrigerator.

For example, each coil set may have its own heat anchor, or both coil sets may share a heat anchor (as shown in fig. 1).

According to an embodiment of the present invention, the uninsulated superconducting coil may be an uninsulated racetrack coil wound with a high temperature superconducting material.

Wherein the high temperature superconducting material can be YBCO strip, GdBCO strip or MgB₂A material.

Compared with the conventional insulated coil, the uninsulated runway type coil is directly wound by a superconducting bare band, and the turns of the coil are uninsulated. The uninsulated coil has the following advantages: a. no turn-to-turn insulation exists, and the volume of the coil is reduced; b. when the superconducting coil is subjected to overcurrent or local hot spots, the current in the superconducting layer flows to the interturn so as to protect the superconducting layer, so that the superconducting coil is not easy to quench, and has high stability and good robustness.

According to one embodiment of the present invention, the vacuum protection enclosure includes an outer dewar shell (e.g., an outer cryogenic dewar shell) 13, an inner dewar shell (e.g., an inner cryogenic dewar shell) 14, and a vacuum layer 1 disposed between the outer dewar shell 13 and the inner dewar shell 14.

That is, a plurality of superconducting coil sets are disposed in the dewar inner shell 14 by disposing a vacuum layer 1 between the dewar outer shell 13 and the dewar inner shell 14 to provide a vacuum environment.

For example, the material of the outer and inner shells of the low temperature dewar may be stainless steel, titanium alloy, aluminum alloy, or nano ceramic composite aluminum alloy.

According to an embodiment of the present invention, the refrigerator includes a primary cold head 2, a secondary cold head 11, and a cold conducting sheet 18, the primary cold head 2 refrigerates the cold shield 15, and the secondary cold head 11 refrigerates the plurality of uninsulated superconducting coils 8 and the refrigeration medium through the cold conducting sheet 18 (i.e., the secondary cold head conducts the primary cold head refrigeration amount to the superconducting coils and the refrigeration medium through the cold conducting sheet).

That is, the primary cold head of the refrigerator can refrigerate the cold shield (for example, refrigerate the cold shield to 65-80K), and the secondary cold head of the refrigerator conducts the cold energy of the primary cold head to the superconducting coil and the refrigerating medium through the cold guide sheet so as to refrigerate the nitrogen fixation in the superconducting coil and the nitrogen fixation tank (for example, refrigerate the superconducting coil and the nitrogen fixation tank to 20-30K).

Therefore, refrigeration of the refrigerating machine and nitrogen fixation energy storage are combined in the mixed refrigeration mode, and the thermal stability of the low-temperature system is improved.

Moreover, each superconducting coil group can be independently refrigerated by one refrigerator, and compared with the mode that a plurality of superconducting coil groups are simultaneously refrigerated by a single refrigerator, the reliability of the refrigerating system is improved. The refrigerator can be a two-stage GM pulse tube refrigerator or a two-stage Stirling refrigerator, and the cold conducting sheet can be made of high-purity oxygen-free copper or aluminum.

According to an embodiment of the present invention, each superconducting coil assembly may further include a high temperature superconducting lead 12 disposed on the excitation loop.

This reduces heat leakage from the field circuit current lead.

According to an embodiment of the invention, each superconducting coil assembly further comprises a plurality of supports 9 for fixedly supporting the uninsulated superconducting coils 8.

Fig. 2 is a schematic diagram showing the arrangement of the shielding layer of the high-temperature superconducting uninsulated magnet according to the embodiment of the invention.

According to one embodiment of the invention, the magnet further comprises a shield layer 16 disposed on the vacuum protected enclosure (i.e., on the dewar shell 13).

For example, the shielding layer 16 may be disposed on all surfaces of the vacuum protection housing, or may be disposed only on one side surface of the vacuum protection housing (as shown in fig. 2, this side may be the side that is likely to be influenced by the external magnetic field).

The shielding layer 16 is arranged on the low-temperature Dewar shell, the harmonic magnetic field generates eddy current on the shielding layer, and the eddy current magnetic field and the harmonic magnetic field are mutually offset, so that the harmonic magnetic field reaching the surface of the superconducting coil is weakened, the alternating current loss of the superconducting coil is finally reduced, and the influence of an external alternating harmonic magnetic field on the superconducting coil is restrained.

According to an embodiment of the present invention, the material of the shielding layer 16 is metal.

For example, the material of the shielding layer 16 may be a metal material with good conductivity.

For example, the shielding layer material may be a metal material with good conductivity, such as aluminum and copper.

According to an embodiment of the present invention, the magnet further comprises a detection device disposed on a surface of each uninsulated superconducting coil 8 for detecting a relevant state parameter of the uninsulated superconducting coil 8.

Thus, health state management of magnet multi-parameter monitoring can be achieved.

According to an embodiment of the invention, the detection device comprises at least one of: temperature detection device, stress detection device, magnetic field detection device and current detection device.

For example, optical fibers can be laid on the surface of the uninsulated superconducting coil, and the temperature of the superconducting coil can be monitored in real time; a strain gauge can be attached to the surface of the superconducting coil to monitor the stress and strain of the superconducting coil in real time; the central magnetic field of the superconducting coil can be monitored in real time through a Hall sensor; the operating current of the superconducting coil can be monitored in real time through a current sensor.

Therefore, once the data of temperature, stress strain, magnetic field and current exceed the safety set values, the magnet can be immediately subjected to demagnetization protection.

According to one embodiment of the invention, the first switching device 4 and the second switching device 17 are both sockets.

That is, the connection and disconnection of the circuit may be achieved through the socket.

For example, when the control motor closes the socket of the excitation circuit, the excitation circuit is connected, otherwise, the excitation circuit is disconnected; similarly, when the control motor closes the receptacle of the flux pump circuit, the flux pump circuit is open and, conversely, is open.

More specifically, for the excitation circuit, the motor is controlled to close the sockets of the excitation circuit, and the external excitation power supplies simultaneously excite the series-connected superconducting coils in the same cold shield (i.e., simultaneously excite the uninsulated superconducting coils in the same superconducting coil group). When the superconducting coils are excited to a target current or a magnetic field, the constant current switch 10 realizes the closed-loop operation of each uninsulated superconducting coil 8, and after the uninsulated superconducting coils operate in a closed-loop manner, the corresponding sockets are disconnected by controlling the motor, so that the heat leakage of the current leads is reduced.

Wherein, the constant current switch can adopt a thermal control type or a magnetic control type.

It should be understood by those skilled in the art that although fig. 1 illustrates a superconducting magnet composed of 4 uninsulated superconducting coils (i.e., two superconducting coil sets), the number of superconducting coils is not limited to 4, and the number of superconducting coil sets is not limited to 2.

In the description of the present invention, it is to be understood that the orientation or positional relationship indicated by the orientation words such as "front, rear, upper, lower, left, right", "lateral, vertical, horizontal" and "top, bottom", etc. are usually based on the orientation or positional relationship shown in the drawings, and are only for convenience of description and simplicity of description, and in the case of not making a reverse description, these orientation words do not indicate and imply that the device or element being referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore, should not be considered as limiting the scope of the present invention; the terms "inner and outer" refer to the inner and outer relative to the profile of the respective component itself.

Spatially relative terms, such as "above … …," "above … …," "above … …," "above," and the like, may be used herein for ease of description to describe one device or feature's spatial relationship to another device or feature as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if a device in the figures is turned over, devices described as "above" or "on" other devices or configurations would then be oriented "below" or "under" the other devices or configurations. Thus, the exemplary term "above … …" can include both an orientation of "above … …" and "below … …". The device may be otherwise variously oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

It should be noted that the terms "first", "second", and the like are used to define the components, and are only used for convenience of distinguishing the corresponding components, and the terms have no special meanings unless otherwise stated, and therefore, the scope of the present invention should not be construed as being limited.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.