Testing device for fast pulse superconducting magnet

Abstract

The invention relates to the technical field of superconducting magnet testing devices, and particularly provides a testing device for a fast pulse superconducting magnet, which comprises a current lead interface box and a horizontal testing Dewar, the current lead interface box comprises a vertical part and a horizontal part, the horizontal part is connected with the vertical part, current leads and low-temperature pipelines are arranged in the vertical part and the horizontal part, and the low-temperature pipelines are used for transmitting cold energy; the horizontal test Dewar is connected with the current lead interface box, an accommodating space is formed in the horizontal test Dewar, and a fast pulse superconducting magnet to be tested is placed in the accommodating space; the fast pulse superconducting magnet is connected with a current lead, and the horizontal test Dewar is connected with a low-temperature pipeline. Through the arrangement of the current lead interface box and the horizontal test Dewar, the flexibility of the system is greatly improved, the operation is more convenient, the limitation of a traditional device on a current lead with a fixed size and a superconducting magnet with a fixed size is broken through, the test device can adapt to magnets with different sizes and configurations, and diversified test requirements are met.

Description

Technical Field

[0001] The present invention relates to the technical field of superconducting magnet testing devices, and in particular to a testing device for fast pulse superconducting magnets. Background Art

[0002] Fast-pulse superconducting magnets are widely used in particle accelerators, high-energy physics experiments, synchrotron radiation sources, magnetic resonance imaging, and other related fields. These magnets typically consist of coils wound with superconducting cables and a room-temperature or cryogenic iron core. The superconducting cables used to wind the coils are directly wound around cooling pipes, which are cooled by liquid helium coolant within the pipes.

[0003] Due to the frequent switching of magnetic fields, fast pulse superconducting magnets generate more eddy currents during operation, which results in the need for greater cooling capacity to maintain their performance and thus stable operation. Therefore, due to the high heat load characteristics of fast pulse superconducting magnets, a more efficient and stable cryogenic system is usually required to ensure that the superconducting state is maintained during the rapid change of magnetic field. Significant mechanical and thermal stresses will also be generated in this process, especially due to the drastic changes in current and magnetic field, the system will be subjected to periodic shocks. The support structure must be designed to absorb and disperse these stresses to prevent related equipment from failing or being damaged.

[0004] Conventional superconducting magnet testing equipment typically consists of a cryogenic test dewar, consisting of a vacuum chamber, a cold shield, a support structure, a safety protection system, and a signal acquisition and transmission system. The vacuum chamber provides a high vacuum environment, reducing heat conduction through the gas, ensuring stable operation of the superconducting magnet in low-temperature environments and isolating the system from external heat. The cold shield, located in the liquid nitrogen temperature range, isolates external thermal radiation, reducing the amount of radiant heat entering the low-temperature region, thereby reducing the cooling load. The support structure uses low-thermal conductivity materials to support and secure the superconducting magnet, maintaining mechanical stability and reducing solid thermal conductivity, preventing heat transfer to the superconducting magnet. The safety protection system, including a safety valve and a rupture disc, prevents excessive pressure inside the dewar, ensuring safe operation under abnormal conditions and avoiding equipment damage or potential hazards. The signal acquisition and transmission system uses sensors to monitor the magnet's operating conditions, including temperature, pressure, and magnetic field, and transmits this data to an external control system for real-time monitoring and analysis of the entire system.

[0005] However, due to the characteristics of fast pulse superconducting magnets such as frequent and large temperature changes and rapid magnetic field changes, the low-temperature test dewar in the existing technology is only applicable to conventional superconducting magnets. When used for fast pulse superconducting magnets, the accuracy and stability of the test process cannot be guaranteed. Summary of the Invention

[0006] The present invention provides a testing device for a fast pulse superconducting magnet, which is used to solve at least one of the above-mentioned problems existing in the testing device in the prior art.

[0007] The present invention provides a testing device for a fast pulse superconducting magnet, comprising: A current lead interface box, comprising a vertical portion and a horizontal portion, wherein the horizontal portion is connected to the vertical portion, and both the vertical portion and the horizontal portion have built-in current leads, wherein the current leads are used to connect to an external power supply and signal processing system; A low-temperature pipeline is provided inside the vertical portion and the horizontal portion; the low-temperature pipeline is used to transmit cold energy; A horizontal test dewar is connected to the horizontal part. The horizontal test dewar has a storage space in which a fast pulse superconducting magnet to be tested is placed. The fast pulse superconducting magnet is connected to the current lead. The horizontal test dewar is connected to the low-temperature pipeline.

[0008] According to a testing device for fast pulse superconducting magnets provided by the present invention, the horizontal test dewar includes a cold shield, a vacuum cavity and a cooling pipe, the cold shield is arranged on the inner side of the vacuum cavity, the cold shield has the accommodating space, the cooling pipe is arranged on the inner side of the cold shield, and the outer periphery of the cooling pipe is provided with an aluminum tube, the aluminum tube is welded to the cold shield; the cooling pipe is connected to the low-temperature pipeline.

[0009] According to the present invention, a testing device for a fast pulse superconducting magnet also includes a first supporting structure and a second supporting structure, wherein the first supporting structure is fixedly connected to the lower inner wall of the vacuum cavity, and the second supporting structure is slidably connected to the lower inner wall of the vacuum cavity, and the second supporting structure can move along the axial direction of the vacuum cavity.

[0010] According to the present invention, a testing device for a fast pulse superconducting magnet further includes a slide rail disposed at the bottom of the second supporting structure, and the slide rail is slidably connected to the second supporting structure.

[0011] According to a testing device for a fast pulse superconducting magnet provided by the present invention, eddy current holes are provided on the cold screen to cut off the eddy current loop.

[0012] According to a testing device for a fast pulse superconducting magnet provided by the present invention, there are a plurality of cryogenic pipelines, wherein some of the cryogenic pipelines are used to cool the current leads.

[0013] According to a test device for a fast pulse superconducting magnet provided by the present invention, there are eight cryogenic pipelines, two of which are used for cooling current leads; and the remaining six cryogenic pipelines are introduced into the horizontal test dewar.

[0014] According to a testing device for a fast pulse superconducting magnet provided by the present invention, among the remaining six cryogenic pipelines, four of the cryogenic pipelines are used to transport cryogenic liquid helium to cool the fast pulse superconducting magnet; the cooling pipe is connected to the remaining two cryogenic pipelines and is used to cool the cold shield.

[0015] According to a testing device for a fast pulse superconducting magnet provided by the present invention, the sliding range of the second supporting structure is 2-4 mm.

[0016] The present invention provides a test device for fast pulse superconducting magnets. The device comprises a current lead interface box and a horizontal test dewar. The current lead interface box has built-in current leads, which are used to connect to an external power supply and signal processing system to ensure stable operation of various sensors and current leads in a low-temperature environment. Cryogenic pipelines are arranged inside the vertical and horizontal parts and are used to transmit cold energy. The horizontal test dewar is connected to the horizontal part and has a storage space inside. A fast pulse superconducting magnet is placed in the storage space. The fast pulse superconducting magnet is connected to the current lead. The horizontal test dewar is connected to the cryogenic pipeline to provide the low-temperature environment required by the fast pulse superconducting magnet. This greatly improves the flexibility of the system and makes operation more convenient. It breaks through the limitations of traditional devices on fixed-size current leads and fixed-size fast pulse superconducting magnets, allowing the test device to adapt to magnets of different sizes and configurations, thereby meeting more diverse testing needs and simplifying experimental settings. The device is particularly suitable for fast pulse superconducting magnets.

[0017] Moreover, the setting of the cold shield, cooling tube and aluminum tube in the horizontal test dewar can avoid the different thermal stresses caused by the different shrinkage coefficients of different metal materials. At the same time, it can also increase the contact area, reduce the contact thermal resistance and improve the thermal conductivity efficiency.

[0018] At the same time, the setting of the first support structure can ensure the precise positioning of the cryogenic pipeline interface connecting the fast pulse superconducting magnet and the current lead interface box during the cooling process, avoiding the instability caused by axial offset; and the setting of the second support structure allows the second support structure to move along the axial direction of the vacuum cavity during the cooling process, which not only prevents damage to the magnet due to excessive thermal stress, but also ensures the influence of periodic mechanical stress and vibration generated during the rapid change of the magnetic field of the fast pulse superconducting magnet, thereby improving the stability and reliability of the cryogenic system during temperature changes. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the present invention or the prior art, a brief introduction is given below to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0020] Figure 1 The figure is a schematic diagram of the appearance structure of the testing device for fast pulse superconducting magnets provided by the present invention.

[0021] Figure 2 It is a cross-sectional view of a testing device for fast pulse superconducting magnets provided by the present invention.

[0022] Figure 3 It is a schematic diagram of the internal structure of the horizontal test dewar provided by the present invention.

[0023] Reference numerals: 1. Current lead interface box; 11. Vertical part; 12. Horizontal part; 2. Current lead; 3. Cryogenic pipeline; 4. Horizontal test dewar; 41. Cold shield; 411. Eddy current hole; 42. Vacuum cavity; 43. Cooling tube; 5. Fast pulse superconducting magnet; 6. First support structure; 7. Second support structure; 8. Slide rail. DETAILED DESCRIPTION

[0024] To make the objectives, technical solutions, and advantages of the present invention more clear, the technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0025] In the description of the embodiments of the present invention, it should be noted that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore should not be understood as limiting the embodiments of the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only and should not be understood as indicating or implying relative importance.

[0026] The following combination Figure 1-3Description: The present invention provides a test device for fast pulse superconducting magnets, including a current lead interface box 1 and a horizontal test dewar 4, to cope with fast pulse superconducting magnets of different performances and sizes, thereby improving the applicability of the test device.

[0027] like Figure 1 and Figure 2 As shown, the current lead interface box 1 includes a vertical portion 11 and a horizontal portion 12. The horizontal portion 12 is connected to the vertical portion 11. Both the vertical portion 11 and the horizontal portion 12 have built-in current leads 2. The current leads 2 are used to connect to the external power supply and signal processing system to ensure the stable operation of various sensors in a low-temperature environment. The cryogenic pipeline 3 is arranged inside the vertical portion 11 and the horizontal portion 12. The cryogenic pipeline 3 is used to transmit cold energy. The horizontal test dewar 4 is connected to the horizontal portion 12; the horizontal test dewar 4 has a storage space, and the storage space is placed in the fast pulse superconducting magnet 5 to be tested; the horizontal test dewar 4 is responsible for providing a low-temperature environment for the normal operation of the fast pulse superconducting magnet 5. The fast pulse superconducting magnet 5 is connected to the current lead 2.

[0028] The present invention divides the test device for fast pulse superconducting magnets into a current lead interface box 1 and a horizontal test dewar 4, which greatly improves the flexibility and operational convenience of the system, breaks through the limitations of traditional test devices on fixed-size current leads 2 and fixed-size superconducting magnets, and enables the test device to be applicable to magnets of different sizes and configurations, thereby meeting more diverse test needs and simplifying experimental settings.

[0029] like Figure 2 and Figure 3 As shown, the horizontal test dewar 4 includes a vacuum chamber 42, a cold shield 41, and a cooling tube 43. The cold shield 41 is mounted inside the vacuum chamber 42 and has a storage space therein. The cooling tube 43 is mounted inside the cold shield 41 and is sheathed with an aluminum tube (not shown) welded to the cold shield 41. The cooling tube 43 is connected to the cryogenic pipeline 3, which not only avoids the different thermal stresses caused by the different contraction coefficients of different metal materials, but also increases the contact area, reduces the contact thermal resistance, and improves the thermal conductivity. The above structural arrangement makes the test device more adaptable to the significant increase in thermal stress caused by the frequent and large temperature changes of fast pulse superconducting magnets.

[0030] The aluminum tube can be provided in multiple sections, and the multiple sections of the aluminum tube are sleeved at intervals on the outer circumference of the cooling tube 43 , which can achieve better heat conduction efficiency and ensure lower material cost.

[0031] like Figure 2 and Figure 3As shown, further, in one embodiment of the present invention, it also includes a first support structure 6 and a second support structure 7. The first support structure 6 and the second support structure 7 are used to support the fast pulse superconducting magnet 5. The first support structure 6 is fixedly connected to the lower inner wall of the vacuum chamber 42 and is a fixed end. It is located at one end of the horizontal test dewar 4 close to the current lead interface box 1, ensuring the precise positioning of the interface of the cryogenic pipeline 3 connected to the current lead interface box 1 during the cooling process, avoiding the instability caused by axial offset. The second support structure 7 is slidably connected to the lower inner wall of the vacuum chamber 42. The second support structure 7 can move along the axial direction of the vacuum chamber 42. The range of the movable distance can generally be set to 2-4 mm, and more preferably, the movable distance is 3 mm. While preventing damage to the magnet due to excessive thermal stress, it ensures the influence of periodic mechanical stress and vibration generated during the rapid change of the magnetic field of the fast pulse magnet, thereby improving the stability and reliability of the cryogenic system during temperature changes.

[0032] When the fast pulse superconducting magnet 5 switches its magnetic field rapidly, it will generate periodic mechanical stress and vibration. The rapidly changing stress is usually not taken into account when designing the test dewar support structure of the steady-state superconducting magnet. This may cause the support structure to fail or the magnet positioning to be inaccurate, affecting the reliability of the test results. For the test of fast pulse superconducting magnets, the mechanical design of the dewar needs to be strengthened to cope with these dynamic stresses and ensure that the support structure can withstand the load caused by rapid changes. Through the arrangement of the first support structure 6 and the second support structure 7, the test device is significantly optimized in dealing with the influence of various external forces (including mechanical stress and thermal stress). This design improves the mechanical stability of the system, especially under the dynamic stress conditions caused by the high-frequency magnetic field switching of the fast pulse magnet, reduces the risk of support structure failure, and ensures the reliability and accuracy of the test.

[0033] See again Figure 2 As shown, further, it also includes a slide rail 8, which is arranged at the bottom of the first support structure 6 and the second support structure 7, and the slide rail 8 and the second support structure 7 are slidably connected to enable the second support structure 7 to move along the axial direction of the vacuum chamber 42.

[0034] See also Figure 3 As shown, in a feasible embodiment of the present invention, the cold shield 41 can be configured as a cylinder with eddy current holes 411 provided therein to cut off the eddy current circuit and effectively reduce the eddy current power. This effectively reduces the negative impact of eddy currents on the overall structure, ensuring system stability and operational efficiency. This configuration not only reduces the additional heat and electromagnetic interference generated by eddy currents, but also reduces heat leakage in the system, further enhancing the stability and accuracy of the fast pulse superconducting magnet 5 during testing.

[0035] It should be noted that when a steady-state superconducting magnet is working, the magnetic field changes relatively slowly, and the eddy current effect and electromagnetic interference are relatively small. Therefore, the electromagnetic shielding design of the dewar of the test device of the steady-state superconducting magnet is relatively simple. However, a fast pulse superconducting magnet will generate a large amount of eddy currents and electromagnetic interference when the magnetic field is quickly switched. The shielding capacity of a conventional dewar may not be sufficient to deal with these problems. The additional heat and electromagnetic interference generated by the eddy currents may affect the accuracy and stability of the magnet and the measurement system. Therefore, in the above-mentioned embodiment of the present invention, the test device of the fast pulse superconducting magnet has a more efficient eddy current suppression design to ensure the accuracy of the test and the stability of the system.

[0036] See again Figure 1 As shown, in a feasible embodiment of the present invention, there are multiple low-temperature pipelines 3, wherein some of the low-temperature pipelines 3 are used to cool the current lead 2 to ensure stable operation of the current lead 2.

[0037] More specifically, there are eight cryogenic pipelines 3, two of which are used to cool the current leads; the remaining six cryogenic pipelines 3 are introduced into the horizontal test dewar 4. Four of the remaining six cryogenic pipelines 3 are used to transport cryogenic liquid helium to cool the fast pulse superconducting magnet 5. The cooling pipe 43 is connected to the remaining two cryogenic pipelines 3 to cool the cold shield 41, thereby effectively reducing heat leakage in the system.

[0038] In addition, it should be noted that the current lead interface box 1 is also equipped with eight low-temperature feedthroughs for connecting with multiple sensors to ensure fast and accurate signal transmission.

[0039] In summary, the present invention provides a test device for fast pulse superconducting magnets, including a current lead interface box 1 and a horizontal test dewar 4. The device is applicable to fast pulse superconducting magnets and can handle fast pulse superconducting magnets of different performance and sizes. The current lead interface box 1 is used to accommodate the current lead 2, connect to the external power supply and signal processing system and safety system, and ensure the stable operation of various sensors and current leads in a low-temperature environment. The horizontal test dewar 4 is connected to the current lead interface box 1 and is responsible for providing the low-temperature environment required by the fast pulse superconducting magnet 5.

[0040] The top of the current lead interface box 1 is equipped with eight cryogenic feedthroughs for connecting to multiple sensors, ensuring fast and accurate signal transmission. Eight cryogenic pipelines 3 are designed inside the current lead interface box, two of which are used to cool the current leads 2, and the remaining six cryogenic pipelines 3 are introduced into the horizontal test dewar 4. Four of the remaining six cryogenic pipelines 3 transport cryogenic liquid helium to cool the fast pulse superconducting magnet 5, and the remaining two are used to cool the cold shield 41, effectively reducing heat leakage in the system.

[0041] The horizontal test dewar 4 found through calculation that the vortex hole 411 is set on the cold shield 41, which can cut off the vortex circuit, effectively reduce the vortex power, and ensure the stability and operation efficiency of the system. Figure 3 As shown. An aluminum tube (not shown in the figure) is sheathed on the outside of the cooling tube 43, and then the cooling tube 43 is welded to the cold screen 41 to avoid different thermal stresses caused by different shrinkage coefficients of different metal materials. It can also increase the contact area, reduce the contact thermal resistance, and improve the thermal conductivity efficiency. The horizontal test dewar 4 adopts a first support structure 6 and a second support structure 7, which is a fixed end and a sliding end. The first support structure 6 close to the current lead interface box 1 side is a fixed support, which ensures the precise positioning of the low-temperature pipeline interface connecting the magnet and the current lead interface box 1 during the cooling process, and avoids the instability caused by axial offset. The second support structure 7 away from the current lead interface box 1 side adopts a sliding design, which allows the second support structure 7 to move in the axial direction of the vacuum chamber 42 during the cooling process, and the movable distance is 3mm.

[0042] In the description of the embodiments of the present invention, it should be noted that, unless otherwise specified or limited, the terms "connected" and "connection" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; mechanical connections, electrical connections; and direct connections or indirect connections through an intermediary. Those skilled in the art will understand the specific meanings of the above terms in the embodiments of the present invention based on specific circumstances.

[0043] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "mode", "specific mode", or "some modes" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or mode are included in at least one embodiment or mode of the embodiment of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or mode. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or modes in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or modes and features of different embodiments or modes described in this specification without contradiction.

[0044] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A test device for fast pulse superconducting magnets, characterized in that: include: A current lead interface box (1) comprises a vertical portion (11) and a horizontal portion (12), wherein the horizontal portion (12) is connected to the vertical portion (11), and both the vertical portion (11) and the horizontal portion (12) have built-in current leads (2), wherein the current leads (2) are used to connect to an external power supply and signal processing system; A low-temperature pipeline (3) is arranged inside the vertical portion (11) and the horizontal portion (12); the low-temperature pipeline (3) is used to transmit cold energy; A horizontal test dewar (4) is connected to the horizontal portion (12); the horizontal test dewar (4) has a storage space inside, and a fast pulse superconducting magnet (5) to be tested is placed in the storage space; the fast pulse superconducting magnet (5) is connected to the current lead (2), and the horizontal test dewar (4) is connected to the cryogenic pipeline (3).

2. The testing device for fast pulse superconducting magnets according to claim 1, characterized in that: The horizontal test dewar (4) comprises a cold shield (41), a vacuum cavity (42) and a cooling pipe (43); the cold shield (41) is sleeved on the inner side of the vacuum cavity (42), and the cold shield (41) has the accommodation space; the cooling pipe (43) is arranged on the inner side of the cold shield (41), and an aluminum pipe is sleeved on the outer periphery of the cooling pipe (43), and the aluminum pipe is welded to the cold shield (41); the cooling pipe (43) is connected to the low-temperature pipeline (3).

3. The testing device for fast pulse superconducting magnet according to claim 2, characterized in that: The vacuum chamber (42) further comprises a first supporting structure (6) and a second supporting structure (7), wherein the first supporting structure (6) is fixedly connected to the lower inner wall of the vacuum chamber (42), and the second supporting structure (7) is slidably connected to the lower inner wall of the vacuum chamber (42), and the second supporting structure (7) is capable of moving along the axial direction of the vacuum chamber (42).

4. The testing device for fast pulse superconducting magnet according to claim 3, characterized in that: It also comprises a slide rail (8) which is arranged at the bottom of the second supporting structure (7), and the slide rail (8) and the second supporting structure (7) are slidably connected.

5. The testing device for fast pulse superconducting magnet according to claim 2, characterized in that: The cold shield (41) is provided with eddy current holes (411) to cut off the eddy current circuit.

6. The testing device for fast pulse superconducting magnet according to claim 2, characterized in that: There are a plurality of low-temperature pipelines (3), wherein some of the low-temperature pipelines (3) are used to cool the current lead (2).

7. The testing device for fast pulse superconducting magnets according to claim 6, characterized in that: There are eight cryogenic pipelines (3), two of which are used to cool the current lead (2); and the remaining six cryogenic pipelines (3) are introduced into the horizontal test dewar (4).

8. The testing device for fast pulse superconducting magnets according to claim 7, characterized in that: Among the remaining six cryogenic pipelines (3), four of the cryogenic pipelines (3) are used to transport cryogenic liquid helium to cool the fast pulse superconducting magnet (5); the cooling pipe (43) is connected to the remaining two cryogenic pipelines (3) and is used to cool the cold shield (41).

9. The testing device for fast pulse superconducting magnets according to claim 4, characterized in that: The sliding range of the second supporting structure (7) is 2-4 mm.

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