An easily adjustable and rapidly cooled superconducting magnet

Abstract

The present invention provides an easily adjustable rapid cooling superconducting magnet, which belongs to the technical field of superconducting magnets. It includes a support base and a cooling adjustment system. Both sides of the top of the support base are fixedly connected with connection seats. The top of the connection 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. The cooling adjustment system includes a temperature monitoring module, a flow rate adjustment module, a pressure adjustment module, and a central control unit. The present invention can significantly improve the cooling speed of the superconducting magnet compared with traditional superconducting magnets, reduce problems such as equipment idleness and increased operating costs caused by long cooling time. At the same time, due to the high efficiency and uniformity of cooling, it also helps to improve the performance stability and service life of the superconducting magnet.

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 improve the cooling speed of the superconducting magnet, reduce the operating cost and has good adaptability.

[0007] To achieve the above object, the present invention adopts the following technical solution: A quickly-cooled superconducting magnet that is easy to adjust, comprising a support base and a cooling adjustment system. On both sides of the top of the support base, connection seats are fixedly connected. On the top of the connection seats, a superconducting magnet assembly is fixedly connected. On the top of the superconducting magnet assembly, a refrigerator assembly is fixedly connected. On one side of the top of the superconducting magnet assembly, a main cooling unit is fixedly connected. On the other side of the top of the superconducting magnet assembly, a pre-cooling unit is fixedly connected. The cooling adjustment system includes a temperature monitoring module, a flow rate adjustment module, a pressure adjustment module, and a central control unit.

[0008] Further, the superconducting magnet assembly includes a housing. The bottom of the housing is fixedly connected to the connection seat. Inside the housing, a first inner shell is fixedly connected. A cooling chamber is formed between the first inner shell and the housing. Inside the first inner shell, a second inner shell is fixedly connected. Inside the second inner shell, a superconducting coil assembly is fixedly connected. The inner wall of the second inner shell is made of oxygen-free copper and is processed with spiral grooves.

[0009] Still further, the refrigerator assembly includes a mounting seat. At the front end and the rear end of the top of the mounting seat, refrigerators are fixedly connected. On one side of the top of the mounting seat, a current lead is fixedly connected. The cold end of the refrigerator is connected to the cooling chamber through a heat conduction connection component.

[0010] Still further, the main cooling unit includes a first outer shell. The bottom of the first outer shell is fixedly connected to the housing. On one side of the bottom inside the first outer shell, a liquid helium storage tank is fixedly connected. On the other side of the bottom inside the first outer shell, a high-pressure pump body is fixedly connected. One side of the high-pressure pump body is communicated with a delivery pipe. The side of the delivery pipe away from the high-pressure pump body is communicated with the liquid helium storage tank. The bottom of the high-pressure pump body is communicated with a stainless steel pipe. The bottom of the stainless steel pipe penetrates the inside of the first outer shell and extends to the inside of the second inner shell. On one side inside the second inner shell, a spraying device is fixedly connected. The bottom of the stainless steel pipe is communicated with the spraying device. The spraying device includes a mounting frame. The surface of the mounting frame is fixedly connected to the inner wall of the second inner shell. On one side of the mounting frame, an annular spraying pipe is fixedly connected. The surface of the annular spraying pipe is communicated with spray nozzles.

[0011] Preferably, the pre-cooling unit includes a liquid nitrogen storage tank, a liquid nitrogen circulation pump, and a heat exchanger. On one side of the top of the housing, a second outer shell is fixedly connected. The liquid nitrogen storage tank, the liquid nitrogen circulation pump, the heat exchanger, and a control valve are all arranged inside the second outer shell. The liquid nitrogen storage tank is communicated with the liquid nitrogen circulation pump through a pipeline. One side of the liquid nitrogen circulation pump is communicated with the heat exchanger through a pipeline. One end of the heat exchanger is connected to the pre-cooling inlet of the cooling chamber through a copper pipe.

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

[0013] Furthermore, the flow rate regulating module uses an electromagnetic flow valve and a flow sensor to control the flow rates of the liquid nitrogen circulation pump and the liquid helium injection device. In the liquid nitrogen circulation system, the flow sensor monitors the actual flow rate of the liquid nitrogen in real time, and the electromagnetic flow regulating valve precisely adjusts the flow rate of the liquid nitrogen according to the instructions of the central control unit. Even further, the pressure regulating module uses pressure sensors, which are respectively installed in the cooling chamber and in the pipeline systems of the liquid nitrogen and the liquid helium, and is equipped with corresponding pressure regulating devices. The pressure regulating device is an electric control valve.

[0014] Preferably, the central control unit uses a central processing unit, which receives all data from the temperature monitoring module, the flow rate monitoring module, and the pressure monitoring module, comprehensively judges according to the target cooling curve of the superconducting magnet and the real-time monitoring data, and issues control instructions to each regulating module.

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

[0016] Preferably, a fixing frame is fixedly connected to the inner cavity of the mounting frame, and one side of the fixing frame is fixedly connected to the annular injection pipe. Furthermore, a clamping block is fixedly connected to the outside of the mounting frame, and the side of the clamping block away from the mounting frame is fixedly connected to the second inner shell. Even further, a mounting groove is opened on the surface of the superconducting coil assembly, a support column is fixedly connected to the inner cavity of the mounting groove, 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 uses a superconducting coil with 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 quick-cooling superconducting magnet with easy adjustment of the present invention are as follows:

[0019] 1. The quick-cooling superconducting magnet with easy adjustment of the present invention uses a superconducting coil with a double-layer composite structure. 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. The outer layer is wrapped with a layer of copper-nickel alloy with a high thermal conductivity. This alloy can not only effectively enhance the mechanical strength of the superconducting coil, but also quickly conduct the heat generated during the operation of the superconducting coil. The superconducting coil adopts a special winding process to form a multi-channel micro-channel structure inside it.

[0020] 2. The easily adjustable rapid cooling superconducting magnet of the present invention selects a high-power cryogenic 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, which is made of copper material. One end is closely attached 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 role of the refrigerator is to assist in maintaining a low-temperature environment during the operation of the superconducting magnet, reducing the evaporation loss of liquid helium. When the superconducting magnet is in the standby state 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 the quench state or needs to further reduce the temperature, the refrigerator and the liquid helium cooling system work together to accelerate the cooling speed. The refrigerator system is also equipped with a temperature control system, which can automatically adjust the refrigeration power according to the real-time temperature feedback of the superconducting magnet to ensure the temperature stability.

[0021] 3. The easily adjustable rapid cooling superconducting magnet of the present invention uses a liquid helium storage tank as the 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 regulation module can accurately adjust the pressure and flow rate of 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.

[0022] 4. The pre-cooling unit in the easily adjustable rapid cooling superconducting magnet of the present invention mainly consists 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 pumps liquid nitrogen out of the storage tank and pressurizes it to make it flow 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 cooling chamber of the superconducting magnet.

[0023] 5. In the cooling regulation 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, which 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 rate of liquid nitrogen in real time. The electromagnetic flow regulating valve accurately adjusts the flow rate of liquid nitrogen according to the instructions of the central control unit. In the liquid helium injection system.

[0024] 6. The present invention combines pressure regulation and flow regulation. The pressure regulation system changes the injection pressure of liquid helium, and at the same time, in cooperation with the feedback of the flow sensor, uses a 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 adverse effects of pressure fluctuations on the cooling effect.

[0025] 7. The central control unit of the present invention incorporates advanced intelligent algorithms. Based on the target cooling curve of the superconducting magnet and real-time monitoring data, it comprehensively judges and issues control instructions to each adjustment module. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 FIG. 6 is a three-dimensional structural schematic diagram of an easily adjustable rapid cooling superconducting magnet according to the present invention;

[0027] Figure 2 FIG. 10 is a schematic diagram of the structure of the first inner shell of an easily adjustable rapid cooling superconducting magnet according to the present invention;

[0028] Figure 3 FIG. 14 is a schematic diagram of the structure of the second inner shell of an easily adjustable rapid cooling superconducting magnet according to the present invention;

[0029] Figure 4 FIG. 18 is a schematic diagram of the structure of the injection device of an easily adjustable rapid cooling superconducting magnet according to the present invention;

[0030] Figure 5 FIG. 22 is a schematic diagram of the structure of the superconducting coil assembly of an easily adjustable rapid cooling superconducting magnet according to the present invention;

[0031] Figure 6 FIG. 26 is a schematic diagram of the structure of the first outer shell of an easily adjustable rapid cooling superconducting magnet according to the present invention;

[0032] Figure 7 FIG. 30 is a schematic diagram of the principle of the cooling adjustment system of an easily adjustable rapid cooling superconducting magnet according to the present invention;

[0033] Figure 8 FIG. 34 is a composition structure diagram of the flow rate adjustment module of an easily adjustable rapid cooling superconducting magnet according to the present invention.

[0034] Explanation of reference numerals in the drawings: 1, support base; 2, connection base; 3, superconducting magnet assembly; 301, housing; 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 OF THE EMBODIMENTS

[0035] In order to more clearly understand the above-mentioned objects, features and advantages of the present invention, the present invention will be further described below with reference to the accompanying drawings and embodiments. It should be noted that, without conflict, the embodiments of the present application and the features in the embodiments may be combined with each other.

[0036] In the following description, many specific details are set forth in order to fully understand the present invention. However, the present invention may also be implemented in other ways different from those described herein. Therefore, the present invention is not limited by the specific embodiments disclosed in the following specification.

[0037] The present invention provides an easily adjustable rapid cooling superconducting magnet, which includes a support base 1 and a cooling adjustment system. Both sides of the top of the support base 1 are fixedly connected with connecting seats 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. 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 rate adjustment module, a pressure adjustment module and a central control unit;

[0038] The superconducting magnet assembly 3 includes a housing 301. The bottom of the housing 301 is fixedly connected to the connecting seat 2. A first inner housing 302 is fixedly connected inside the housing 301. A cooling chamber is formed between the first inner housing 302 and the housing 301. A second inner housing 303 is fixedly connected inside the first inner housing 302. A superconducting coil assembly 304 is fixedly connected inside the second inner housing 303. The inner wall of the second inner housing 303 is made of oxygen-free copper and is processed with spiral grooves. The refrigerator assembly 4 includes a mounting base 401. Refrigerators 402 are fixedly connected to the front end and the rear end of the top of the mounting base 401. A current lead 403 is fixedly connected to one side of the top of the mounting base 401. The cold ends of the refrigerators 402 are connected to the cooling chamber through a heat conduction connecting component. The main cooling unit 5 includes a first outer housing 501. The bottom of the first outer housing 501 is fixedly connected to the housing 301. A liquid helium storage tank 502 is fixedly connected to one side of the bottom inside the first outer housing 501. A high-pressure pump body 503 is fixedly connected to the other side of the bottom inside the first outer housing 501. One side of the high-pressure pump body 503 communicates with a delivery pipe 504. The side of the delivery pipe 504 away from the high-pressure pump body 503 communicates with the liquid helium storage tank 502. The bottom of the high-pressure pump body 503 communicates with a stainless steel pipe 505. The bottom of the stainless steel pipe 505 penetrates through the inside of the first outer housing 501 and extends to the inside of the second inner housing 303. An injection device 506 is fixedly connected to one side inside the second inner housing 303. The bottom of the stainless steel pipe 505 communicates with 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 housing 303. An annular injection pipe 5062 is fixedly connected to one side of the mounting frame 5061. Nozzles 5063 are communicated with the surface of the annular injection pipe 5062. The pre-cooling unit 6 includes a liquid nitrogen storage tank, a liquid nitrogen circulation pump and a heat exchanger. A second outer housing 7 is fixedly connected to one side of the top of the housing 301. The liquid nitrogen storage tank, the liquid nitrogen circulation pump, the heat exchanger and the control valve are all arranged inside the second outer housing 7. The liquid nitrogen storage tank is communicated with the liquid nitrogen circulation pump through a pipeline. One side of the liquid nitrogen circulation pump is communicated with the heat exchanger through a pipeline. One end of the heat exchanger is connected to the pre-cooling inlet of the cooling chamber through a copper pipe.

[0039] With the above technical solution, by setting the refrigerator assembly 4, after the superconducting magnet reaches the operating temperature, it assists in maintaining the low-temperature environment. During the operation of the superconducting magnet, even with good heat insulation measures, a certain amount of heat will still be introduced, resulting in the evaporation of liquid helium. The refrigerator can absorb this part of the heat, reduce the evaporation loss of liquid helium, and reduce the replenishment frequency of liquid helium.

[0040] In addition, the cooling regulation system plays a crucial coordinating role. It can reasonably control the operating states of the refrigerator, the main cooling unit 5, and the pre-cooling unit 6 according to parameters such as the real-time temperature and pressure of the superconducting magnet. When the temperature of the superconducting magnet is relatively high and it 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 at the same time, the refrigerator can be started for preheating or preparation work. When the temperature of the superconducting magnet approaches the operating temperature or is already in the stable operation stage, the cooling regulation system will adjust the power of the refrigerator according to the heat load situation, and at the same time appropriately reduce the working intensity to achieve efficient and energy-saving low-temperature maintenance. For example, after the temperature of the superconducting magnet stabilizes at the superconducting operating temperature, the cooling regulation system will, according to the information fed back by the temperature sensor, let the refrigerator undertake part of the task of maintaining the low temperature, reduce the evaporation of liquid helium, and at the same time, by controlling components such as control valves, intermittently supplement the cooling medium to maintain the balance of the cooling system.

[0041] Furthermore, the inner chamber in the cooling chamber is the placement space for the superconducting coil. Its inner wall is made of high-purity oxygen-free copper, and dense spiral grooves are machined on the copper wall. These grooves 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 the heat transfer to the inside. At the top and bottom of the cooling chamber, a plurality of evenly distributed cooling medium inlets and outlets are respectively provided so that the cooling medium can enter and flow out of the cooling channels evenly.

[0042] Preferably, a helium recovery device is also provided in the main cooling unit 5 to recover the evaporated helium during the cooling process and reduce the loss of helium.

[0043] Furthermore, the temperature monitoring module uses temperature sensors, which are respectively arranged in the cooling chamber, the pipeline systems of 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 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 rate of liquid nitrogen in real time.

[0044] The flow regulation module uses an electromagnetic flow valve and a flow sensor to control the flow rates 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 rate of liquid nitrogen in real time, and the electromagnetic flow regulating valve accurately adjusts the flow rate of liquid nitrogen according to the instructions of the central control unit.

[0045] Additionally, the pressure regulation module uses pressure sensors, which are respectively installed in the cooling chamber and the pipeline systems of liquid nitrogen and liquid helium, and is equipped with corresponding pressure regulation devices. The pressure regulation device is an electric control valve. The electromagnetic flow control valve precisely adjusts the flow rate of liquid nitrogen according to the instructions of the central control unit. In the liquid helium injection system, through the combination of pressure regulation and flow regulation, the pressure regulation system changes the injection pressure of liquid helium, and at the same time, in cooperation with the feedback of the flow sensor, uses the needle valve structure to precisely control the injection flow rate of liquid helium. In the liquid nitrogen and liquid helium pipelines, the pressure regulation device can stabilize the conveying pressure of the cooling medium and prevent adverse effects on the cooling effect caused by pressure fluctuations.

[0046] Preferably, the central control unit uses a central processing unit. The central processing unit receives all data from the temperature monitoring module, the flow monitoring module, and the pressure monitoring module, comprehensively judges according to the target cooling curve of the superconducting magnet and the real-time monitoring data, and issues control instructions to each regulation module. The central control unit is built-in with advanced intelligent algorithms, comprehensively judges according to the target cooling curve of the superconducting magnet and the real-time monitoring data, and issues control instructions to each regulation module.

[0047] With the above technical solution, a connecting plate 8 is fixedly connected to the surface of the first inner shell 302. The other side of the connecting plate 8 is fixedly connected to a mounting plate 9. Mounting holes are formed in the top of the mounting plate 9. The first inner shell 302 is fixedly connected to the inner wall of the housing 301 through the mounting holes. The first inner shell 302 can be firmly installed on the inner wall of the housing 301 through the connecting plate 8, the mounting plate 9, and the mounting holes, ensuring the stability of the installation of the first inner shell 302.

[0048] In addition, a fixing frame 10 is fixedly connected to the inner cavity of the mounting frame 5061. One side of the fixing frame 10 is fixedly connected to the annular injection pipe 5062. A clamping block 11 is fixedly connected to the outside of the mounting frame 5061. The side of the clamping block 11 away from the mounting frame 5061 is fixedly connected to the second inner shell 303. Mounting grooves 12 are formed on the surface of the superconducting coil assembly 304. A support column 13 is fixedly connected to the inner cavity of the mounting groove 12. 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 uses a superconducting coil with 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. The fixing frame 10 can be used to install the annular injection pipe 5062, ensuring the stability of the installation of the annular injection pipe 5062. At the same time, the clamping block 11 is used to install the annular injection pipe 5062, improving the stability of the annular injection pipe 5062 during injection under high pressure. One end of the support column 13 is firmly fixed to the inner wall of the cooling chamber through a special cryogenic adhesive, which can not only provide a stable supporting force for the superconducting coil, but also minimize the heat conduction from the support structure to the superconducting coil, avoiding affecting the superconducting performance of the superconducting coil due to heat conduction.

[0049] The following further describes the easily adjustable rapid cooling type superconducting magnet of the present invention in conjunction with specific embodiments.

[0050] As Figures 1 - 8As shown in the figure, the present invention provides an easily adjustable rapid cooling superconducting magnet, which includes a support base 1 and a cooling adjustment system. Both sides of the top of the support base 1 are fixedly connected with connecting seats 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. 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 rate adjustment module, a pressure adjustment module and a central control unit. The superconducting magnet assembly 3 includes a housing 301. The bottom of the housing 301 is fixedly connected with the connecting seat 2. A first inner shell 302 is fixedly connected to the inner cavity of the housing 301. A cooling chamber is formed between the first inner shell 302 and the housing 301. A second inner shell 303 is fixedly connected to the inner cavity of the first inner shell 302. A superconducting coil assembly 304 is fixedly connected to the inner cavity of the second inner shell 303. The inner wall of the second inner shell 303 is made of oxygen-free copper and is processed with spiral grooves. The refrigerator assembly 4 includes a mounting seat 401. Refrigerators 402 are fixedly connected to the front end and the rear end of the top of the mounting seat 401. A current lead 403 is fixedly connected to one side of the top of the mounting seat 401. The cold ends of the refrigerators 402 are connected to the cooling chamber through heat conduction connection components. The main cooling unit 5 includes a first outer shell 501. The bottom of the first outer shell 501 is fixedly connected with the housing 301. A liquid helium storage tank 502 is fixedly connected to one side of the bottom of the inner cavity of the first outer shell 501. A high-pressure pump body 503 is fixedly connected to the other side of the bottom of the inner cavity of the first outer shell 501. One side of the high-pressure pump body 503 is communicated with a delivery pipe 504. The side of the delivery pipe 504 away from the high-pressure pump body 503 is communicated with the liquid helium storage tank 502. The bottom of the high-pressure pump body 503 is communicated with a stainless steel pipe 505. The bottom of the stainless steel pipe 505 penetrates through the inner cavity of the first outer shell 501 and extends to the inner cavity of the second inner shell 303. An injection device 506 is fixedly connected to one side of the inner cavity of the second inner shell 303. The bottom of the stainless steel pipe 505 is communicated with the injection device 506. The injection device 506 includes a mounting frame 5061. The surface of the mounting frame 5061 is fixedly connected with the inner wall of the second inner shell 303. An annular injection pipe 5062 is fixedly connected to one side of the mounting frame 5061. Nozzles 5063 are communicated with the surface of the annular injection pipe 5062. The pre-cooling unit 6 includes a liquid nitrogen storage tank, a liquid nitrogen circulation pump and a heat exchanger. A second outer shell 7 is fixedly connected to one side of the top of the housing 301. The liquid nitrogen storage tank, the liquid nitrogen circulation pump, the heat exchanger and a control valve are all arranged in the inner cavity of the second outer shell 7. The liquid nitrogen storage tank is communicated with the liquid nitrogen circulation pump through a pipeline. One side of the liquid nitrogen circulation pump is communicated with the heat exchanger through a pipeline. One end of the heat exchanger is connected to the pre-cooling inlet of the cooling chamber through a copper pipe.

[0051] Specifically, the following describes the specific settings and functions of its superconducting magnet assembly 3, refrigerator assembly 4, main cooling unit 5 and pre-cooling unit 6.

[0052] As Figure 1 and Figure 5 shown, the superconducting magnet assembly 3 includes a housing 301. The bottom of the housing 301 is fixedly connected to the connecting seat 2. A first inner housing 302 is fixedly connected inside the housing 301. A cooling chamber is formed between the first inner housing 302 and the housing 301. A second inner housing 303 is fixedly connected inside the first inner housing 302. A superconducting coil assembly 304 is fixedly connected inside the second inner housing 303. The inner wall of the second inner housing 303 is made of oxygen-free copper, and a spiral groove is machined on its inner wall. The refrigerator assembly 4 includes a mounting base 401. Refrigerators 402 are fixedly connected to the front end and the rear end of the top of the mounting base 401. A current lead 403 is fixedly connected to one side of the top of the mounting base 401. The cold ends of the refrigerators 402 are connected to the cooling chamber through a heat conduction connecting component.

[0053] The achieved effect of the entire superconducting magnet assembly 3 is that a superconducting coil with a double-layer composite structure is adopted. The inner layer is made of high-purity niobium-tin superconducting material, which has excellent superconducting properties and can operate stably under strong magnetic fields. The outer layer is wrapped with a copper-nickel alloy with a high thermal conductivity. This alloy can not only effectively enhance the mechanical strength of the superconducting coil but also quickly conduct the heat generated during the operation of the superconducting coil. The superconducting coil adopts a special winding process to form a multi-channel microchannel structure inside it.

[0054] As Figure 3 、 Figure 4 and Figure 6 shown, the main cooling unit 5 includes a first outer housing 501. The bottom of the first outer housing 501 is fixedly connected to the housing 301. A liquid helium storage tank 502 is fixedly connected to one side of the bottom inside the first outer housing 501. A high-pressure pump body 503 is fixedly connected to the other side of the bottom inside the first outer housing 501. A delivery pipe 504 communicates with one side of the high-pressure pump body 503. The other side of the delivery pipe 504 away from the high-pressure pump body 503 communicates with the liquid helium storage tank 502. A stainless steel pipe 505 communicates with the bottom of the high-pressure pump body 503. The bottom of the stainless steel pipe 505 penetrates the inside of the first outer housing 501 and extends to the inside of the second inner housing 303. An injection device 506 is fixedly connected to one side inside the second inner housing 303. The bottom of the stainless steel pipe 505 communicates with 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 housing 303. An annular injection pipe 5062 is fixedly connected to one side of the mounting frame 5061. Nozzles 5063 communicate with the surface of the annular injection pipe 5062.

[0055] The effect achieved by the entire main cooling unit 5 is that a high-power cryocooler 402 is selected, such as a pulse tube cryocooler 402 or a GM cryocooler 402. The cold head of the cryocooler 402 is connected to the cooling chamber through a heat conduction connecting component, which is made of copper material. One end is closely attached to the cold head of the cryocooler 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 cryocooler 402 is to assist in maintaining a low-temperature environment during the operation of the superconducting magnet, reducing the evaporation loss of liquid helium. When the superconducting magnet is in the standby state or the heat load is small, the cryocooler 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 the quench state or needs to further reduce the temperature, the cryocooler 402 works in cooperation with the liquid helium cooling system to accelerate the cooling speed. The cryocooler 402 system is also equipped with a temperature control system, which can automatically adjust the refrigeration power according to the real-time temperature feedback of the superconducting magnet to ensure temperature stability.

[0056] Such as Figure 1 and Figure 2 As shown in the figure, 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 housing 301 is fixedly connected with a 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 communicated with the liquid nitrogen circulation pump through a pipeline. One side of the liquid nitrogen circulation pump is communicated with the heat exchanger through a pipeline. One end of the heat exchanger is connected to the pre-cooling inlet of the cooling chamber through a copper pipe.

[0057] The effect achieved by the entire pre-cooling unit 6 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 pumps out the liquid nitrogen from the storage tank and pressurizes it to make it flow through the heat exchanger at a certain flow rate. The heat exchanger adopts an efficient finned structure to increase the heat exchange area between the liquid nitrogen and the superconducting magnet cooling chamber.

[0058] The working process of the easy-to-adjust rapid cooling superconducting magnet is as follows:

[0059] Step S1: Start the liquid nitrogen circulation pump, and the liquid nitrogen exchanges heat with the superconducting magnet cooling chamber in the heat exchanger; transmit the data to the central control unit, and the flow rate adjustment module dynamically adjusts the flow rate of the liquid nitrogen according to the instructions of the central control unit based on the temperature change situation;

[0060] Start the liquid nitrogen circulation pump. Draw liquid nitrogen from the liquid nitrogen storage tank and pressurize it for transportation to the heat exchanger through a control valve according to a 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 start dropping rapidly. The temperature monitoring module monitors the temperature changes of key parts of the superconducting magnet in real time, such as the superconducting coil and the inlet and outlet of the cooling channels, and transmits the data to the central control unit. The flow rate adjustment module dynamically adjusts the flow rate of liquid nitrogen according to the instructions of the central control unit based on the temperature change situation. For example, when the temperature drop rate of the superconducting magnet is too fast or too slow, appropriately reduce or increase the liquid nitrogen flow rate to maintain a stable cooling rate and make it cool down along the preset cooling curve. The pressure adjustment module monitors and stabilizes the pressure in the liquid nitrogen pipeline system and the cooling chamber to prevent the heat exchange efficiency from being affected by pressure fluctuations or causing equipment damage.

[0061] Step S2: When the temperature of the superconducting magnet drops to the preset transition temperature, the central control unit automatically switches the cooling mode; the pressure adjustment system precisely controls the injection pressure and flow rate of liquid helium;

[0062] 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 channels of the cooling chamber in the form of tiny droplets through the liquid helium injection device 506. The pressure adjustment system precisely controls the injection pressure and flow rate of liquid helium to ensure that the liquid helium is evenly distributed in the cooling channels and fully absorbs heat, further reducing the temperature of the superconducting magnet. During this process, the refrigeration machine system also starts to work in coordination. The cold head of the refrigeration machine absorbs heat from the outer wall of the cooling chamber through a heat conduction connection component to assist the liquid helium cooling, accelerating the cooling speed and reducing the liquid helium evaporation loss. The cooling adjustment system continuously monitors and adjusts various parameters, such as the liquid helium flow rate and the refrigeration machine power, to ensure that the superconducting magnet smoothly transitions to the main cooling stage and continues to cool down to the superconducting operating temperature.

[0063] Step S3: When the superconducting magnet reaches the superconducting operating temperature, the cooling adjustment system enters the maintenance mode;

[0064] When the superconducting magnet reaches the superconducting operating temperature, the cooling adjustment system enters the maintenance mode. The central control unit fine-tunes the refrigeration machine 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 minor heat loss, maintaining the temperature of the superconducting magnet within a stable range below the superconducting critical temperature. Regularly check the liquid levels of the liquid nitrogen storage tank and the liquid helium storage tank 502 and the operating status of the refrigeration machine to ensure the continuous and stable operation of the cooling system. At the same time, monitor parameters such as the pressure and temperature of the superconducting magnet through the cooling adjustment system to promptly detect potential fault hazards or abnormal situations, such as blockage of the cooling channels and local overheating of the superconducting coil, and take corresponding measures for treatment.

[0065] 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 at the same time reduce the refrigerator power;

[0066] If the superconducting magnet needs to stop running, first gradually reduce the liquid helium flow rate of the liquid helium injection device 506 and at the same time reduce the refrigerator power. During this process, the temperature monitoring module closely monitors the temperature rise of the superconducting magnet. When the liquid helium flow rate is reduced to zero and the temperature of the superconducting magnet rises to a certain safe range, such as above the superconducting critical temperature but still in a low-temperature state, stop the operation of the refrigerator. Finally, turn off the liquid nitrogen circulation pump and related control valves of the pre-cooling unit 6, check and maintain the entire cooling system, and get ready for the next startup.

[0067] The above are only the preferred embodiments of the present invention, and are not intended to limit the present invention in other forms. Any person skilled in the art may use the technical content disclosed above to make changes or modifications into equivalent embodiments with equivalent changes and apply them to other fields. However, as long as it does not depart from the technical solution content of the present invention, any simple modification, equivalent change and modification made to the above embodiments based on the technical essence of the present invention still fall 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; 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; The inner cavity of the mounting frame (5061) is fixedly connected to a mounting frame (10), one side of the mounting frame (10) is fixedly connected to the annular injection pipe (5062), the outer side of the mounting frame (5061) is fixedly connected to a 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), a mounting groove (12) is provided on the surface of the superconducting coil assembly (304), 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, 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; 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).

2. The easily adjustable fast cooling superconducting magnet according to claim 1, 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.

3. The easily adjustable fast cooling superconducting magnet according to claim 1, 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).

4. 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.

5. 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).

6. 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.

7. 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.

8. 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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