Quick cooling type superconducting magnet easy to adjust

Abstract

The invention provides an easy-to-adjust rapid cooling type superconducting magnet, and belongs to the technical field of superconducting magnets, the easy-to-adjust rapid cooling type superconducting magnet comprises a supporting seat and a cooling adjusting system, the two sides of the top of the supporting seat are fixedly connected with connecting seats, and the tops of the connecting seats are fixedly connected with superconducting magnet assemblies; the top of the superconducting magnet assembly is fixedly connected with a refrigerator assembly, one side of the top of the superconducting magnet assembly is fixedly connected with a main cooling unit, and the other side of the top of the superconducting magnet assembly is fixedly connected with a pre-cooling unit. The cooling adjusting system comprises a temperature monitoring module, a flow adjusting module, a pressure adjusting module and a central control unit. Compared with a traditional superconducting magnet, the cooling speed of the superconducting magnet can be remarkably increased, the problems of equipment idling, operation cost increase and the like caused by long cooling time are reduced, and meanwhile due to cooling efficiency and uniformity, the performance stability of the superconducting magnet can be improved, and the service life of the superconducting magnet can be prolonged.

Description

Technical Field

[0001] The invention belongs to the technical field of superconducting magnets, and in particular relates to an easily adjustable fast-cooling superconducting magnet. Background Art

[0002] With the rapid development of modern science and technology, superconducting magnets occupy an indispensable position in many cutting-edge scientific research and high-end technology application fields. In the field of mineral processing, the uniform, stable and strong magnetic field generated by superconducting magnets is the key factor for the full separation of weak magnetic materials in minerals, and it is of great significance for the separation research of fine weak magnetic minerals. In terms of particle accelerators, superconducting magnets provide the magnetic field environment required for acceleration and confinement of charged particles, helping scientists explore the mysteries of the world of microscopic particles and promoting the progress of basic physics. In the field of nuclear fusion research, such as the International Thermonuclear Experimental Reactor (ITER) project, superconducting magnets are used to confine high-temperature plasma and are one of the core technologies for realizing the dream of controlled nuclear fusion, a clean energy.

[0003] The superconducting properties of superconducting magnets rely on extremely low temperature environments. Most traditional superconducting materials need to be near the temperature of liquid helium (about 4.2K) to present a zero resistance state, thereby generating and maintaining a strong magnetic field. However, there are many challenges in achieving and maintaining such low temperature conditions. On the one hand, traditional superconducting magnet cooling systems usually use relatively simple immersion cooling or single cooling medium circulation cooling methods. These methods have obvious limitations in cooling speed, and it often takes several hours or even longer to cool from room temperature to superconducting operating temperature.

[0004] With the increasing application scenarios of superconducting magnets and the continuous improvement of their performance requirements, such as the need for superconducting magnets to quickly switch magnetic field states or restore superconducting performance in a short time in actual mineral processing production, the slow cooling speed of traditional cooling systems can no longer meet these requirements. In addition, the slow cooling process is also accompanied by high operating costs, including the consumption of large amounts of liquid helium and economic losses caused by long-term equipment downtime. At the same time, in some special applications, such as superconducting magnet equipment in the aerospace field, due to space and resource limitations, more stringent requirements are placed on the volume, weight and cooling efficiency of the cooling system, and traditional cooling technology is even more difficult to adapt.

[0005] Therefore, developing a superconducting magnet cooling technology that can significantly increase the cooling speed, reduce operating costs and have good adaptability has become a key issue that needs to be urgently addressed in the current superconducting magnet field. Summary of the invention

[0006] Based on the problems existing in the prior art, the present invention proposes an easily adjustable fast-cooling superconducting magnet, which can significantly increase the cooling speed of the superconducting magnet, reduce the operating cost and has good adaptability.

[0007] In order to achieve the above-mentioned purpose, the present invention adopts the following technical scheme: an easily adjustable fast-cooling superconducting magnet, comprising a support seat and a cooling adjustment system, both sides of the top of the support seat are fixedly connected with a connecting seat, the top of the connecting seat is fixedly connected with a superconducting magnet assembly, the top of the superconducting magnet assembly is fixedly connected with a refrigerator assembly, one side of the top of the superconducting magnet assembly is fixedly connected with a main cooling unit, and the other side of the top of the superconducting magnet assembly is fixedly connected with a pre-cooling unit, and the cooling adjustment system includes a temperature monitoring module, a flow adjustment module, a pressure adjustment module and a central control unit.

[0008] Furthermore, the superconducting magnet assembly includes a shell, the bottom of which is fixedly connected to a connecting seat, the inner cavity of the shell is fixedly connected to a first inner shell, a cooling chamber is formed between the first inner shell and the shell, the inner cavity of the first inner shell is fixedly connected to a second inner shell, the inner cavity of the second inner shell is fixedly connected to a superconducting coil assembly, and the inner wall of the second inner shell is made of oxygen-free copper, and a spiral groove is processed on the inner wall.

[0009] Furthermore, the refrigerator assembly includes a mounting seat, the front and rear ends of the top of the mounting seat are fixedly connected to a refrigerator, one side of the top of the mounting seat is fixedly connected to a current lead, and the cold end of the refrigerator is connected to the cooling chamber through a heat conduction connecting component.

[0010] Furthermore, the main cooling unit includes a first shell, the bottom of which is fixedly connected to the shell, one side of the bottom of the inner cavity of the first shell is fixedly connected to a liquid helium storage tank, the other side of the bottom of the inner cavity of the first shell is fixedly connected to a high-pressure pump body, one side of the high-pressure pump body is connected to a delivery pipe, the side of the delivery pipe away from the high-pressure pump body is connected to the liquid helium storage tank, the bottom of the high-pressure pump body is connected to a stainless steel pipe, the bottom of the stainless steel pipe passes through the inner cavity of the first shell and extends to the inner cavity of the second inner shell, one side of the inner cavity of the second inner shell is fixedly connected to an injection device, the bottom of the stainless steel pipe is connected to the injection device, the injection device includes a mounting frame, the surface of the mounting frame is fixedly connected to the inner wall of the second inner shell, one side of the mounting frame is fixedly connected to an annular injection pipe, and the surface of the annular injection pipe is connected to a nozzle.

[0011] Preferably, the pre-cooling unit includes a liquid nitrogen storage tank, a liquid nitrogen circulation pump and a heat exchanger, one side of the top of the shell is fixedly connected to a second shell, the liquid nitrogen storage tank, the liquid nitrogen circulation pump, the heat exchanger and the control valve are all arranged in the inner cavity of the second shell, the liquid nitrogen storage tank is connected to the liquid nitrogen circulation pump through a pipeline, one side of the liquid nitrogen circulation pump is connected to the heat exchanger through a pipeline, and one end of the heat exchanger is connected to the pre-cooling inlet of the cooling chamber through a copper tube.

[0012] Preferably, the temperature monitoring module adopts temperature sensors, which are respectively arranged inside the cooling chamber, in the pipeline systems of the main cooling unit and the pre-cooling unit.

[0013] Furthermore, the flow regulating module uses electromagnetic flow valves and flow sensors to control the flow of liquid nitrogen circulation pumps and liquid helium injection devices. In the liquid nitrogen circulation system, the flow sensor monitors the actual flow of liquid nitrogen in real time, and the electromagnetic flow regulating valve accurately adjusts the flow of liquid nitrogen according to the instructions of the central control unit. Furthermore, the pressure regulating module uses pressure sensors, which are installed in the cooling chamber and the pipeline systems of liquid nitrogen and liquid helium, and are equipped with corresponding pressure regulating devices, which are electric regulating valves.

[0014] Preferably, the central control unit adopts a central processing unit, which receives all data from the temperature monitoring module, the flow monitoring module and the pressure monitoring module, and makes comprehensive judgments and issues control instructions to each adjustment module based on the target cooling curve of the superconducting magnet and the real-time monitoring data.

[0015] Preferably, a connecting plate is fixedly connected to the surface of the first inner shell, a mounting plate is fixedly connected to the other side of the connecting plate, a mounting hole is opened on the top of the mounting plate, and the first inner shell is fixedly connected to the inner wall of the shell through the mounting hole.

[0016] Preferably, the inner cavity of the mounting frame is fixedly connected to a fixing frame, and one side of the fixing frame is fixedly connected to the annular injection pipe. Further, the outer side of the mounting frame is fixedly connected to a clamping block, and the side of the clamping block away from the mounting frame is fixedly connected to the second inner shell. Further, a mounting groove is provided on the surface of the superconducting coil assembly, and the inner cavity of the mounting groove is fixedly connected to a support column, and the material of the support column is a ceramic material, and the side of the support column away from the mounting groove is fixedly connected to the second inner shell.

[0017] Furthermore, the superconducting coil assembly adopts a superconducting coil of a composite structure, the inner layer of the superconducting coil is a niobium-tin superconducting material, and the outer layer is wrapped with a layer of copper-nickel alloy.

[0018] Compared with the prior art, the advantages and positive effects of the easily adjustable fast cooling superconducting magnet of the present invention are: 1. The easily adjustable fast-cooling superconducting magnet of the present invention adopts a double-layer composite structure superconducting coil, the inner layer is a high-purity niobium-tin superconducting material, which has excellent superconducting properties and can operate stably under a strong magnetic field, and the outer layer is wrapped with a layer of copper-nickel alloy with high thermal conductivity, which can not only effectively enhance the mechanical strength of the superconducting coil, but also quickly conduct the heat generated by the superconducting coil during operation. The superconducting coil adopts a special winding process to form a multi-channel microchannel structure inside it.

[0019] 2. The fast-cooling superconducting magnet that is easy to adjust of the present invention uses a high-power low-temperature refrigerator, such as a pulse tube refrigerator or a GM refrigerator. The cold head of the refrigerator is connected to the cooling chamber through a heat conduction connecting component. The connecting component is made of copper material, one end of which is tightly fitted to the cold head of the refrigerator, and the other end is in contact with the outer wall of the cooling chamber to ensure good heat conduction. The function of the refrigerator is to assist in maintaining a low-temperature environment and reduce the evaporation loss of liquid helium during the operation of the superconducting magnet. When the superconducting magnet is in standby mode or the heat load is small, the refrigerator can work independently to maintain the temperature of the superconducting magnet below the superconducting critical temperature, reducing the dependence on the liquid helium cooling system. At the same time, when the superconducting magnet recovers from a quenched state or needs to further reduce the temperature, the refrigerator and the liquid helium cooling system work together to speed up the cooling speed. The refrigerator system is also equipped with a temperature control system, which can automatically adjust the cooling power according to the real-time temperature feedback of the superconducting magnet to ensure temperature stability.

[0020] 3. The easily adjustable fast-cooling superconducting magnet of the present invention uses a liquid helium storage tank as a storage container for liquid helium. The injection device injects liquid helium into the cooling channel of the cooling chamber in the form of tiny droplets. The pressure regulating module can accurately adjust the pressure and flow rate of the liquid helium injection according to the cooling requirements of the superconducting magnet to ensure that the liquid helium is evenly distributed in the cooling channel and fully absorbs heat.

[0021] 4. The pre-cooling unit in the easily adjustable rapid cooling superconducting magnet of the present invention is mainly composed of a liquid nitrogen storage tank, a liquid nitrogen circulation pump and a heat exchanger. The liquid nitrogen storage tank is used to store liquid nitrogen. The liquid nitrogen circulation pump extracts liquid nitrogen from the storage tank and pressurizes it so that it passes through the heat exchanger at a certain flow rate. The heat exchanger adopts an efficient fin structure to increase the heat exchange area between the liquid nitrogen and the superconducting magnet cooling chamber.

[0022] 5. In the cooling and regulating system of the easily adjustable rapid cooling superconducting magnet of the present invention, the temperature sensor is made of a material with good low-temperature adaptability, can accurately measure the temperature changes at different positions, and transmit the temperature data to the central control unit in real time, the flow sensor monitors the actual flow of liquid nitrogen in real time, and the electromagnetic flow regulating valve accurately adjusts the flow of liquid nitrogen in the liquid helium injection system according to the instructions of the central control unit.

[0023] 6. The present invention combines pressure regulation with flow regulation. The pressure regulation system changes the injection pressure of liquid helium and cooperates with the flow sensor feedback to accurately control the injection flow of liquid helium using a needle valve structure. In the liquid nitrogen and liquid helium pipelines, the pressure regulating device can stabilize the delivery pressure of the cooling medium and prevent pressure fluctuations from having an adverse effect on the cooling effect.

[0024] 7. The central control unit of the present invention has an advanced intelligent algorithm built in, which makes a comprehensive judgment and issues control instructions to each adjustment module based on the target cooling curve of the superconducting magnet and real-time monitoring data. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 A schematic diagram of the three-dimensional structure of an easily adjustable rapid cooling superconducting magnet according to the present invention; Figure 2 A schematic diagram of the first inner shell structure of the easily adjustable rapid cooling superconducting magnet according to the present invention; Figure 3 A schematic diagram of the second inner shell structure of the easily adjustable rapid cooling superconducting magnet according to the present invention; Figure 4 A schematic diagram of the structure of an injection device for a fast-cooling superconducting magnet that is easily adjustable according to the present invention; Figure 5 A schematic diagram of the structure of a superconducting coil assembly of an easily adjustable rapid cooling superconducting magnet according to the present invention; Figure 6 A schematic diagram of a first shell structure of an easily adjustable rapid cooling superconducting magnet according to the present invention; Figure 7 A schematic diagram of the principle of a cooling regulation system for a fast-cooling superconducting magnet that is easily adjustable according to the present invention; Figure 8 The figure is a structural diagram of the flow regulating module of the fast-cooling superconducting magnet that is easy to adjust according to the present invention.

[0026] Explanation of the reference numerals in the accompanying drawings: 1. support base; 2. connecting base; 3. superconducting magnet assembly; 301. shell; 302. first inner shell; 303. second inner shell; 304. superconducting coil assembly; 4. refrigerator assembly; 401. mounting base; 402. refrigerator; 403. current lead; 5. main cooling unit; 501. first outer shell; 502. liquid helium storage tank; 503. high-pressure pump body; 504. delivery pipe; 505. stainless steel pipe; 506. injection device; 5061. mounting frame; 5062. annular injection pipe; 5063. nozzle; 6. pre-cooling unit; 7. second outer shell; 8. connecting plate; 9. mounting plate; 10. fixing frame; 11. clamping block; 12. mounting groove; 13. support column. DETAILED DESCRIPTION

[0027] In order to more clearly understand the above-mentioned purpose, features and advantages of the present invention, the present invention is further described below in conjunction with the accompanying drawings and embodiments. It should be noted that the embodiments of the present application and the features in the embodiments can be combined with each other without conflict.

[0028] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways than those described herein. Therefore, the present invention is not limited to the specific embodiments of the following disclosure.

[0029] The present invention provides an easily adjustable fast cooling superconducting magnet, which comprises a support seat 1 and a cooling adjustment system, wherein both sides of the top of the support seat 1 are fixedly connected with a connecting seat 2, the top of the connecting seat 2 is fixedly connected with a superconducting magnet assembly 3, the top of the superconducting magnet assembly 3 is fixedly connected with a refrigerator assembly 4, one side of the top of the superconducting magnet assembly 3 is fixedly connected with a main cooling unit 5, and the other side of the top of the superconducting magnet assembly 3 is fixedly connected with a pre-cooling unit 6, and the cooling adjustment system comprises a temperature monitoring module, a flow adjustment module, a pressure adjustment module and a central control unit; The superconducting magnet assembly 3 includes a shell 301, the bottom of the shell 301 is fixedly connected to the connecting seat 2, the inner cavity of the shell 301 is fixedly connected to the first inner shell 302, a cooling chamber is formed between the first inner shell 302 and the shell 301, the inner cavity of the first inner shell 302 is fixedly connected to the second inner shell 303, the inner cavity of the second inner shell 303 is fixedly connected to the superconducting coil assembly 304, the inner wall of the second inner shell 303 is made of oxygen-free copper, and the inner wall thereof is processed with a spiral groove, the refrigerator assembly 4 includes a mounting seat 401, the front end of the top of the mounting seat 401 The first and rear ends of the mounting base 401 are fixedly connected to a refrigerator 402, a current lead 403 is fixedly connected to one side of the top of the mounting base 401, the cold end of the refrigerator 402 is connected to the cooling chamber through a heat conduction connection component, the main cooling unit 5 includes a first shell 501, the bottom of the first shell 501 is fixedly connected to the shell 301, one side of the bottom of the inner cavity of the first shell 501 is fixedly connected to a liquid helium storage tank 502, the other side of the bottom of the inner cavity of the first shell 501 is fixedly connected to a high-pressure pump body 503, one side of the high-pressure pump body 503 is connected to a delivery pipe 504, and the delivery pipe 504 is connected to the delivery pipe 504. The side of the tube 504 away from the high-pressure pump body 503 is connected to the liquid helium storage tank 502. The bottom of the high-pressure pump body 503 is connected to a stainless steel tube 505. The bottom of the stainless steel tube 505 passes through the inner cavity of the first outer shell 501 and extends to the inner cavity of the second inner shell 303. One side of the inner cavity of the second inner shell 303 is fixedly connected to an injection device 506. The bottom of the stainless steel tube 505 is connected to the injection device 506. The injection device 506 includes a mounting frame 5061. The surface of the mounting frame 5061 is fixedly connected to the inner wall of the second inner shell 303. The mounting frame 506 1 is fixedly connected to one side of the housing 301 with an annular injection pipe 5062, and the surface of the annular injection pipe 5062 is connected to a nozzle 5063. The pre-cooling unit 6 includes a liquid nitrogen storage tank, a liquid nitrogen circulation pump and a heat exchanger. One side of the top of the shell 301 is fixedly connected to a second shell 7. The liquid nitrogen storage tank, the liquid nitrogen circulation pump, the heat exchanger and the control valve are all arranged in the inner cavity of the second shell 7. The liquid nitrogen storage tank is connected to the liquid nitrogen circulation pump through a pipeline, one side of the liquid nitrogen circulation pump is connected to the heat exchanger through a pipeline, and one end of the heat exchanger is connected to the pre-cooling inlet of the cooling chamber through a copper tube.

[0030] By adopting the above technical solution, a refrigerator assembly 4 is provided to assist in maintaining a low-temperature environment after the superconducting magnet reaches the operating temperature. During the operation of the superconducting magnet, even with good insulation measures, a certain amount of heat will still be introduced, causing the liquid helium to evaporate. The refrigerator can absorb this part of the heat, reduce the evaporation loss of the liquid helium, and reduce the frequency of replenishing the liquid helium.

[0031] In addition, the cooling and regulating system plays a key coordinating role. It can reasonably control the working status of the refrigerator, the main cooling unit 5 and the pre-cooling unit 6 according to the real-time temperature, pressure and other parameters of the superconducting magnet. When the temperature of the superconducting magnet is high and is in the rapid cooling stage, the control system mainly relies on the main cooling unit 5 and the pre-cooling unit 6 for cooling, and the refrigerator can be started for preheating or preparation. When the temperature of the superconducting magnet is close to the working temperature or is already in the stable operation stage, the cooling and regulating system will adjust the power of the refrigerator according to the heat load and appropriately reduce the working intensity to achieve efficient and energy-saving low-temperature maintenance. For example, after the temperature of the superconducting magnet is stabilized at the superconducting working temperature, the cooling and regulating system will let the refrigerator take on part of the task of maintaining the low temperature according to the information fed back by the temperature sensor to reduce the evaporation of liquid helium. At the same time, by controlling the control valve and other components, the cooling medium is intermittently replenished to maintain the balance of the cooling system.

[0032] Furthermore, the inner chamber in the cooling chamber is the placement space for the superconducting coil, and its inner wall is made of high-purity oxygen-free copper. The copper wall is processed with dense spiral grooves, which are connected to the microchannels of the superconducting coil to form a complete cooling channel network. The outer chamber is used to isolate external heat and reduce heat transfer to the inside. At the top and bottom of the cooling chamber, multiple evenly distributed cooling medium inlets and outlets are respectively arranged so that the cooling medium can evenly enter and flow out of the cooling channel.

[0033] Preferably, a helium recovery device is also provided in the main cooling unit 5 to recover the helium evaporated during the cooling process to reduce the loss of helium.

[0034] Furthermore, the temperature monitoring module adopts temperature sensors, which are respectively arranged in the pipeline systems of the cooling chamber, the main cooling unit 5 and the pre-cooling unit 6. The temperature sensors are made of materials with good low-temperature adaptability, can accurately measure temperature changes at different positions, and transmit temperature data to the central control unit in real time. The flow sensor monitors the actual flow of liquid nitrogen in real time.

[0035] The flow regulating module uses an electromagnetic flow valve and a flow sensor to control the flow of the liquid nitrogen circulation pump and the liquid helium injection device 506. In the liquid nitrogen circulation system, the flow sensor monitors the actual flow of liquid nitrogen in real time, and the electromagnetic flow regulating valve accurately adjusts the flow of liquid nitrogen according to the instructions of the central control unit.

[0036] In addition, the pressure regulating module adopts a pressure sensor, which is respectively installed in the cooling chamber and the pipeline system of liquid nitrogen and liquid helium, and is equipped with a corresponding pressure regulating device. The pressure regulating device is an electric regulating valve. The electromagnetic flow regulating valve accurately adjusts the flow rate of liquid nitrogen according to the instruction of the central control unit. In the liquid helium injection system, the pressure regulating system changes the injection pressure of liquid helium by combining pressure regulation with flow regulation. At the same time, it cooperates with the feedback of the flow sensor and uses the needle valve structure to accurately control the injection flow rate of liquid helium. In the liquid nitrogen and liquid helium pipelines, the pressure regulating device can stabilize the delivery pressure of the cooling medium to prevent pressure fluctuations from having an adverse effect on the cooling effect.

[0037] Preferably, the central control unit adopts a central processing unit, which receives all data from the temperature monitoring module, the flow monitoring module and the pressure monitoring module, and makes comprehensive judgments and issues control instructions to each adjustment module based on the target cooling curve of the superconducting magnet and the real-time monitoring data. The central control unit has a built-in advanced intelligent algorithm, and makes comprehensive judgments and issues control instructions to each adjustment module based on the target cooling curve of the superconducting magnet and the real-time monitoring data.

[0038] By adopting the above technical solution, a connecting plate 8 is fixedly connected to the surface of the first inner shell 302, a mounting plate 9 is fixedly connected to the other side of the connecting plate 8, a mounting hole is opened on the top of the mounting plate 9, and the first inner shell 302 is fixedly connected to the inner wall of the shell 301 through the mounting hole. The first inner shell 302 can be firmly installed on the inner wall of the shell 301 through the connecting plate 8, the mounting plate 9 and the mounting hole, thereby ensuring the stability of the installation of the first inner shell 302.

[0039] In addition, the inner cavity of the mounting frame 5061 is fixedly connected to the fixing frame 10, one side of the fixing frame 10 is fixedly connected to the annular injection pipe 5062, the outer side of the mounting frame 5061 is fixedly connected to the clamping block 11, the side of the clamping block 11 away from the mounting frame 5061 is fixedly connected to the second inner shell 303, the surface of the superconducting coil assembly 304 is provided with a mounting groove 12, the inner cavity of the mounting groove 12 is fixedly connected to a support column 13, the material of the support column 13 is a ceramic material, the side of the support column 13 away from the mounting groove 12 is fixedly connected to the second inner shell 303, the superconducting coil assembly 304 adopts a superconducting coil of a composite structure, and the superconducting wire The inner layer of the coil is a niobium-tin superconducting material, and the outer layer is wrapped with a layer of copper-nickel alloy. The annular injection tube 5062 can be installed through the fixing frame 10, which ensures the stability of the installation of the annular injection tube 5062. At the same time, the annular injection tube 5062 is installed by the clamping block 11 to improve the stability of the annular injection tube 5062 under high pressure. One end of the support column 13 is firmly fixed to the inner wall of the cooling chamber by a special low-temperature adhesive, which can not only provide a stable supporting force for the superconducting coil, but also minimize the heat conduction from the supporting structure to the superconducting coil, thereby avoiding the superconducting performance of the superconducting coil being affected by heat conduction.

[0040] The easily adjustable rapid cooling superconducting magnet of the present invention is further described below in conjunction with specific embodiments.

[0041] like Figure 1-Figure 8As shown, the present invention provides an easily adjustable fast-cooling superconducting magnet, including a support seat 1 and a cooling adjustment system, both sides of the top of the support seat 1 are fixedly connected with a connecting seat 2, the top of the connecting seat 2 is fixedly connected with a superconducting magnet assembly 3, the top of the superconducting magnet assembly 3 is fixedly connected with a refrigerator assembly 4, one side of the top of the superconducting magnet assembly 3 is fixedly connected with a main cooling unit 5, and the other side of the top of the superconducting magnet assembly 3 is fixedly connected with a pre-cooling unit 6, the cooling adjustment system includes a temperature monitoring module, a flow adjustment module, a pressure adjustment module and a central control unit, the superconducting magnet assembly 3 includes a shell 301, the bottom of the shell 301 is fixedly connected to the connecting seat 2, and the inner The first inner shell 302 is fixedly connected to the cavity, and a cooling chamber is formed between the first inner shell 302 and the shell 301. The inner cavity of the first inner shell 302 is fixedly connected to the second inner shell 303. The inner cavity of the second inner shell 303 is fixedly connected to the superconducting coil assembly 304. The inner wall of the second inner shell 303 is made of oxygen-free copper, and its inner wall is processed with spiral grooves. The refrigerator assembly 4 includes a mounting seat 401, and the front and rear ends of the top of the mounting seat 401 are fixedly connected to the refrigerator 402. One side of the top of the mounting seat 401 is fixedly connected to the current lead 403. The cold end of the refrigerator 402 is connected to the cooling chamber through a heat conduction connection component. The main cooling unit 5 includes a first outer shell 501, a first outer shell 502, and a second outer shell 503. The bottom of the shell 501 is fixedly connected to the shell body 301, one side of the bottom of the inner cavity of the first shell 501 is fixedly connected to the liquid helium storage tank 502, the other side of the bottom of the inner cavity of the first shell 501 is fixedly connected to the high-pressure pump body 503, one side of the high-pressure pump body 503 is connected to the delivery pipe 504, the side of the delivery pipe 504 away from the high-pressure pump body 503 is connected to the liquid helium storage tank 502, the bottom of the high-pressure pump body 503 is connected to the stainless steel pipe 505, the bottom of the stainless steel pipe 505 passes through the inner cavity of the first shell 501 and extends to the inner cavity of the second inner shell 303, one side of the inner cavity of the second inner shell 303 is fixedly connected to the injection device 506, the bottom of the stainless steel pipe 505 is connected to the injection device 506, and the injection device 506 is connected to the injection device 506. The injection device 506 includes a mounting frame 5061, the surface of the mounting frame 5061 is fixedly connected to the inner wall of the second inner shell 303, one side of the mounting frame 5061 is fixedly connected to an annular injection pipe 5062, the surface of the annular injection pipe 5062 is connected to a nozzle 5063, the pre-cooling unit 6 includes a liquid nitrogen storage tank, a liquid nitrogen circulation pump and a heat exchanger, one side of the top of the shell 301 is fixedly connected to the second outer shell 7, the liquid nitrogen storage tank, the liquid nitrogen circulation pump, the heat exchanger and the control valve are all arranged in the inner cavity of the second outer shell 7, the liquid nitrogen storage tank is connected to the liquid nitrogen circulation pump through a pipeline, one side of the liquid nitrogen circulation pump is connected to the heat exchanger through a pipeline, and one end of the heat exchanger is connected to the pre-cooling inlet of the cooling chamber through a copper tube.

[0042] The specific configuration and functions of the superconducting magnet assembly 3, refrigerator assembly 4, main cooling unit 5 and pre-cooling unit 6 are described in detail below.

[0043] like Figure 1 and Figure 5 As shown, the superconducting magnet assembly 3 includes a shell 301, the bottom of the shell 301 is fixedly connected to the connecting seat 2, the inner cavity of the shell 301 is fixedly connected to the first inner shell 302, a cooling chamber is formed between the first inner shell 302 and the shell 301, the inner cavity of the first inner shell 302 is fixedly connected to the second inner shell 303, the inner cavity of the second inner shell 303 is fixedly connected to the superconducting coil assembly 304, the inner wall of the second inner shell 303 is made of oxygen-free copper, and the inner wall thereof is processed with spiral grooves, the refrigerator assembly 4 includes a mounting seat 401, the front end and the rear end of the top of the mounting seat 401 are fixedly connected to the refrigerator 402, one side of the top of the mounting seat 401 is fixedly connected to the current lead 403, and the cold end of the refrigerator 402 is connected to the cooling chamber through a heat conduction connecting component.

[0044] The effect achieved by the entire superconducting magnet assembly 3 is that a superconducting coil with a double-layer composite structure is adopted, the inner layer is a high-purity niobium-tin superconducting material, which has excellent superconducting properties and can operate stably under a strong magnetic field, and the outer layer is wrapped with a layer of copper-nickel alloy with high thermal conductivity, which can not only effectively enhance the mechanical strength of the superconducting coil, but also quickly conduct the heat generated by the superconducting coil during operation. The superconducting coil adopts a special winding process to form a multi-channel microchannel structure inside it.

[0045] like Figure 3 , Figure 4 and Figure 6 As shown, the main cooling unit 5 includes a first shell 501, the bottom of the first shell 501 is fixedly connected to the shell 301, one side of the bottom of the inner cavity of the first shell 501 is fixedly connected to the liquid helium storage tank 502, the other side of the bottom of the inner cavity of the first shell 501 is fixedly connected to the high-pressure pump body 503, one side of the high-pressure pump body 503 is connected to the delivery pipe 504, the side of the delivery pipe 504 away from the high-pressure pump body 503 is connected to the liquid helium storage tank 502, the bottom of the high-pressure pump body 503 is connected to the stainless steel pipe 505, the stainless steel pipe The bottom of 505 passes through the inner cavity of the first outer shell 501 and extends to the inner cavity of the second inner shell 303. A spray device 506 is fixedly connected to one side of the inner cavity of the second inner shell 303. The bottom of the stainless steel tube 505 is connected to the spray device 506. The spray device 506 includes a mounting frame 5061. The surface of the mounting frame 5061 is fixedly connected to the inner wall of the second inner shell 303. An annular spray pipe 5062 is fixedly connected to one side of the mounting frame 5061. The surface of the annular spray pipe 5062 is connected to the nozzle 5063.

[0046] The effect achieved by the entire main cooling unit 5 is that a high-power low-temperature refrigerator 402 is selected, such as a pulse tube refrigerator 402 or a GM refrigerator 402, and the cold head of the refrigerator 402 is connected to the cooling chamber through a heat conduction connecting component. The connecting component is made of copper material, one end of which is tightly fitted to the cold head of the refrigerator 402, and the other end is in contact with the outer wall of the cooling chamber to ensure good heat conduction. The function of the refrigerator 402 is to assist in maintaining a low-temperature environment and reduce the evaporation loss of liquid helium during the operation of the superconducting magnet. When the superconducting magnet is in a standby state or the heat load is small, the refrigerator 402 can work independently to maintain the temperature of the superconducting magnet below the superconducting critical temperature, reducing the dependence on the liquid helium cooling system. At the same time, when the superconducting magnet recovers from a quenched state or needs to further reduce the temperature, the refrigerator 402 works in coordination with the liquid helium cooling system to speed up the cooling speed. The refrigerator 402 system is also equipped with a temperature control system, which can automatically adjust the cooling power according to the real-time temperature feedback of the superconducting magnet to ensure the stability of the temperature.

[0047] like Figure 1 and Figure 2 As shown, the pre-cooling unit 6 includes a liquid nitrogen storage tank, a liquid nitrogen circulation pump and a heat exchanger. One side of the top of the shell 301 is fixedly connected to the second shell 7. The liquid nitrogen storage tank, the liquid nitrogen circulation pump, the heat exchanger and the control valve are all arranged in the inner cavity of the second shell 7. The liquid nitrogen storage tank is connected to the liquid nitrogen circulation pump through a pipeline, one side of the liquid nitrogen circulation pump is connected to the heat exchanger through a pipeline, and one end of the heat exchanger is connected to the pre-cooling inlet of the cooling chamber through a copper tube.

[0048] The effect achieved by the entire pre-cooling unit 6 is that it is mainly composed of a liquid nitrogen storage tank, a liquid nitrogen circulation pump and a heat exchanger. The liquid nitrogen storage tank is used to store liquid nitrogen. The liquid nitrogen circulation pump draws liquid nitrogen from the storage tank and pressurizes it so that it passes through the heat exchanger at a certain flow rate. The heat exchanger adopts an efficient fin structure to increase the heat exchange area between liquid nitrogen and the superconducting magnet cooling chamber.

[0049] The easy-to-adjust, fast-cooling superconducting magnet works as follows: Step S1, start the liquid nitrogen circulation pump, and the liquid nitrogen performs heat exchange with the superconducting magnet cooling chamber in the heat exchanger; transmit the data to the central control unit, and the flow regulating module dynamically adjusts the flow of liquid nitrogen according to the temperature change according to the instruction of the central control unit; Start the liquid nitrogen circulation pump, and extract the liquid nitrogen from the liquid nitrogen storage tank and pressurize it to the heat exchanger through the control valve according to the preset initial flow rate. The liquid nitrogen exchanges heat with the superconducting magnet cooling chamber in the heat exchanger, taking away a large amount of heat, causing the temperature of the superconducting magnet to drop rapidly. The temperature monitoring module monitors the temperature changes of key parts of the superconducting magnet, such as the superconducting coil and the inlet and outlet of the cooling channel in real time, and transmits the data to the central control unit. The flow regulation module dynamically adjusts the flow of liquid nitrogen according to the instructions of the central control unit and the temperature changes. For example, when the temperature of the superconducting magnet drops too fast or too slow, the liquid nitrogen flow rate is appropriately reduced or increased to maintain a stable cooling rate so that it can cool down along the preset cooling curve. The pressure regulation module monitors and stabilizes the pressure in the liquid nitrogen pipeline system and the cooling chamber to prevent pressure fluctuations from affecting the heat exchange efficiency or causing equipment damage.

[0050] Step S2: When the temperature of the superconducting magnet drops to a preset transition temperature, the central control unit automatically switches to a cooling mode; the pressure regulating system accurately controls the injection pressure and flow rate of the liquid helium; When the temperature of the superconducting magnet drops to the preset transition temperature, the central control unit automatically switches the cooling mode and starts the main cooling unit 5. The liquid helium in the liquid helium storage tank 502 is sprayed into the cooling channel of the cooling chamber in the form of tiny droplets through the liquid helium spray device 506. The pressure regulating system accurately controls the spray pressure and flow of the liquid helium to ensure that the liquid helium is evenly distributed in the cooling channel and fully absorbs heat, thereby further reducing the temperature of the superconducting magnet. During this process, the refrigerator system also starts to work in coordination. The cold head of the refrigerator absorbs heat from the outer wall of the cooling chamber through the heat conduction connection component to assist in the cooling of the liquid helium, speed up the cooling speed and reduce the evaporation loss of the liquid helium. The cooling regulating system continuously monitors and adjusts various parameters, such as the liquid helium flow rate, the refrigerator power, etc., to ensure that the superconducting magnet smoothly transitions to the main cooling stage and continues to cool down to the superconducting working temperature.

[0051] Step S3: When the superconducting magnet reaches the superconducting operating temperature, the cooling and regulating system enters a maintenance mode; When the superconducting magnet reaches the superconducting operating temperature, the cooling and regulating system enters the maintenance mode. The central control unit fine-tunes the refrigerator power and the operating parameters of the liquid helium injection device 506 according to the information fed back by the temperature monitoring module to compensate for the temperature rise caused by external heat input or internal small heat loss, maintain the temperature of the superconducting magnet in a stable range below the superconducting critical temperature, and regularly check the liquid levels of the liquid nitrogen storage tank and the liquid helium storage tank 502 and the operating status of the refrigerator to ensure the continuous and stable operation of the cooling system. At the same time, the pressure, temperature and other parameters of the superconducting magnet are monitored through the cooling and regulating system to promptly discover potential fault hazards or abnormal conditions, such as cooling channel blockage, local overheating of the superconducting coil, etc., and take corresponding measures to deal with them.

[0052] Step S4: if the superconducting magnet needs to stop running, first gradually reduce the liquid helium flow rate of the liquid helium injection device and reduce the power of the refrigerator; If the superconducting magnet needs to stop running, first gradually reduce the liquid helium flow of the liquid helium injection device 506 and reduce the refrigerator power. In this process, the temperature monitoring module closely monitors the temperature recovery of the superconducting magnet. When the liquid helium flow is reduced to zero and the temperature of the superconducting magnet rises to a certain safety range, such as higher than the superconducting critical temperature but still in a low temperature state, stop the refrigerator. Finally, turn off the liquid nitrogen circulation pump and related control valves of the pre-cooling unit 6, and inspect and maintain the entire cooling system to prepare for the next startup.

[0053] The above are only preferred embodiments of the present invention and are not intended to limit the present invention in other forms. Any technician familiar with the profession may use the technical contents disclosed above to change or modify them into equivalent embodiments with equivalent changes and apply them to other fields. However, any simple modification, equivalent change and modification made to the above embodiments based on the technical essence of the present invention without departing from the technical solution of the present invention still falls within the protection scope of the technical solution of the present invention.

Claims

1. An easily adjustable fast cooling superconducting magnet, comprising a support (1) and a cooling adjustment system, characterized in that: Both sides of the top of the support seat (1) are fixedly connected to a connection seat (2), the top of the connection seat (2) is fixedly connected to a superconducting magnet assembly (3), the top of the superconducting magnet assembly (3) is fixedly connected to a refrigerator assembly (4), one side of the top of the superconducting magnet assembly (3) is fixedly connected to a main cooling unit (5), and the other side of the top of the superconducting magnet assembly (3) is fixedly connected to a pre-cooling unit (6), and the cooling regulation system comprises a temperature monitoring module, a flow regulation module, a pressure regulation module and a central control unit.

2. The easily adjustable fast cooling superconducting magnet according to claim 1, characterized in that: The superconducting magnet assembly (3) comprises a shell (301), the bottom of the shell (301) is fixedly connected to the connecting seat (2), the inner cavity of the shell (301) is fixedly connected to a first inner shell (302), a cooling chamber is formed between the first inner shell (302) and the shell (301), the inner cavity of the first inner shell (302) is fixedly connected to a second inner shell (303), the inner cavity of the second inner shell (303) is fixedly connected to a superconducting coil assembly (304), and the inner wall of the second inner shell (303) is made of oxygen-free copper, and the inner wall is processed with a spiral groove.

3. The easily adjustable fast cooling superconducting magnet according to claim 2, characterized in that: The refrigerator assembly (4) comprises a mounting seat (401), the front end and the rear end of the top of the mounting seat (401) are fixedly connected to a refrigerator (402), one side of the top of the mounting seat (401) is fixedly connected to a current lead (403), and the cold end of the refrigerator (402) is connected to the cooling chamber via a heat conduction connection component.

4. The easily adjustable fast cooling superconducting magnet according to claim 1, characterized in that: The main cooling unit (5) comprises a first outer shell (501), the bottom of the first outer shell (501) is fixedly connected to the housing (301), one side of the bottom of the inner cavity of the first outer shell (501) is fixedly connected to a liquid helium storage tank (502), the other side of the bottom of the inner cavity of the first outer shell (501) is fixedly connected to a high-pressure pump body (503), one side of the high-pressure pump body (503) is connected to a delivery pipe (504), a side of the delivery pipe (504) away from the high-pressure pump body (503) is connected to the liquid helium storage tank (502), the bottom of the high-pressure pump body (503) is connected to a stainless steel pipe (505), the bottom of the stainless steel pipe (505) passes through the inner cavity of the first outer shell (501) and extends to the inner cavity of the second inner shell (303), one side of the inner cavity of the second inner shell (303) is fixedly connected to an injection device (506), and the bottom of the stainless steel pipe (505) is connected to the injection device (506).

5. The easily adjustable fast cooling superconducting magnet according to claim 4, characterized in that: The injection device (506) comprises a mounting frame (5061), the surface of the mounting frame (5061) being fixedly connected to the inner wall of the second inner shell (303), an annular injection pipe (5062) being fixedly connected to one side of the mounting frame (5061), and the surface of the annular injection pipe (5062) being connected to a nozzle (5063).

6. The easily adjustable fast cooling superconducting magnet according to claim 1, characterized in that: The pre-cooling unit (6) comprises a liquid nitrogen storage tank, a liquid nitrogen circulation pump and a heat exchanger; one side of the top of the shell (301) is fixedly connected to a second shell (7); the liquid nitrogen storage tank, the liquid nitrogen circulation pump, the heat exchanger and the control valve are all arranged in the inner cavity of the second shell (7); the liquid nitrogen storage tank is connected to the liquid nitrogen circulation pump via a pipeline; one side of the liquid nitrogen circulation pump is connected to the heat exchanger via a pipeline; one end of the heat exchanger is connected to the pre-cooling inlet of the cooling chamber via a copper tube.

7. The easily adjustable fast cooling superconducting magnet according to claim 1, characterized in that: The temperature monitoring module uses temperature sensors which are respectively arranged inside the cooling chamber, in the pipeline systems of the main cooling unit (5) and the pre-cooling unit (6).

8. The easily adjustable fast cooling superconducting magnet according to claim 1, characterized in that: The flow regulating module uses an electromagnetic flow valve and a flow sensor to control the flow of a liquid nitrogen circulation pump and a liquid helium injection device (506). In the liquid nitrogen circulation system, the flow sensor monitors the actual flow of liquid nitrogen in real time, and the electromagnetic flow regulating valve accurately adjusts the flow of liquid nitrogen according to the instructions of the central control unit.

9. The easily adjustable fast cooling superconducting magnet according to claim 1, characterized in that: The pressure regulating module adopts a pressure sensor, which is respectively installed in the cooling chamber and the pipeline system of liquid nitrogen and liquid helium, and is equipped with a corresponding pressure regulating device, which is an electric regulating valve.

10. The easily adjustable fast cooling superconducting magnet according to claim 1, characterized in that: The central control unit adopts a central processing unit, which receives all data from the temperature monitoring module, the flow monitoring module and the pressure monitoring module, and makes comprehensive judgments and issues control instructions to each adjustment module according to the target cooling curve of the superconducting magnet and the real-time monitoring data.

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