Shut-off system for superconducting magnet and cooling unit

Abstract

FIELD: superconductors.SUBSTANCE: invention can be used to disconnect a superconducting magnet from a refrigeration unit. The superconducting magnet disconnect system from the refrigeration unit comprises a helium gas piping assembly, a cold head, a set of self-sealing joints, a set of two-position four-way valves, a compressor and a compressor power supply. The compressor and the cooling head are connected by a helium gas pipe assembly, the helium gas is used as a medium in contact with the heat interaction region, and self-sealing joints are provided at the connection and disconnection points of the helium gas pipes.EFFECT: elimination of freezing in the area of thermal interaction, a reduction in the time of transition from the shutdown mode to the reconnection mode of the system, and an increase in the reliability of the shutdown system for the superconducting magnet and the refrigeration unit.10 cl, 2 dwg

Description

[0001] This application claims priority to Chinese Patent Application No. 202410456368.2, entitled "SYSTEM FOR DISCONNECTING SUPERCONDUCTING MAGNET FROM REFRIGERATION UNIT", filed in the National Intellectual Property Administration (China) on April 16, 2024, which is hereby incorporated by reference in its entirety. Technical Field

[0002] The present application relates to the field of superconductors and, in particular, to a system for detaching a superconducting magnet from a refrigeration unit (assembly). BACKGROUND

[0003] Superconducting magnet, as the most important core component of the maglev train, is mainly used to generate strong magnetic field required for the traction, levitation and control of the maglev train.

[0004] A superconducting magnet must undergo relevant performance tests at the prototype stage to meet high safety and reliability requirements during service. Some tests require disconnecting the superconducting magnet from the operating refrigeration system, such as for off-state testing. After the test, it must be reconnected to the refrigeration system to remove the heat generated during the off-state period and restore the internal temperature of the superconducting magnet. It is desirable that this disconnection and reconnection process be generally lossless and reversible, so that the proper internal temperature state of the superconducting magnet allows for subsequent off-state testing. This temperature state directly affects the performance of the superconducting magnet.

[0005] In known devices for separating a superconducting magnet from a refrigeration unit, the thermal contact area is directly exposed to air during separation. Before reconnection, a long time is required to resolve problems such as freezing in the thermal contact area, which affects the testing efficiency of the superconducting magnet and the temperature of the superconducting coils. Furthermore, foreign gas may enter during reconnection, affecting the recovery of the superconducting magnet after reconnection to the refrigeration unit. In general, the device for separating a superconducting magnet from a refrigeration unit exhibits low reliability. DISCLOSURE OF THE INVENTION

[0006] Taking this into account, a system for separating a superconducting magnet from a refrigeration unit according to the present application is proposed, which can solve the problem of low reliability of a conventional device for separating a superconducting magnet from a refrigeration unit.

[0007] In order to solve the above problem, the following solutions are provided according to this application.

[0008] The system for separating the superconducting magnet from the refrigeration unit includes a set of helium gas pipes, a cold head, a set of self-sealing connectors, a set of two-position four-way valves, a compressor and a power supply for supplying electricity to the compressor.

[0009] The helium gas pipe set includes a first helium gas pipe and a second helium gas pipe.

[0010] The cold head comprises an outlet pipe connected to the compressor return pipe via a first helium gas supply line, and an inlet pipe connected to the compressor outlet pipe via a second helium gas line. Each of the cold head outlet pipe, cold head inlet pipe, compressor return pipe, and compressor outlet pipe is provided with a self-sealing connector for connecting or disconnecting the helium gas lines.

[0011] The two-position four-way valve set includes a first two-position four-way valve and a second two-position four-way valve. The first two-position four-way valve is connected between the outlet pipe and the inlet pipe of the cooling head and is configured to control the cooling head in a disconnected operating state or a reconnected state. The second two-position four-way valve is connected between the return pipe and the outlet pipe of the compressor and is configured to control the compressor in a pressure-balanced state or a normal state.

[0012] Optional, additional ball valve kit is included.

[0013] The ball valve set includes a first ball valve and a second ball valve. The first ball valve is located in the compressor return pipe and is configured to close the compressor return pipe during maintenance. The second ball valve is located in the compressor outlet pipe and is configured to close the compressor outlet pipe during maintenance.

[0014] Optionally, a set of pressure gauges is additionally included to indicate the pressure in the helium gas pipelines.

[0015] The pressure gauge set includes a first pressure gauge connected to a first two-position four-way valve, and a second pressure gauge connected to a second two-position four-way valve.

[0016] Optionally, a set of needle valves is additionally included to relieve pressure.

[0017] The needle valve set includes a first needle valve connected to a first two-position four-way valve, and a second needle valve connected to a second two-position four-way valve.

[0018] Optionally, an adjustable pressure relief valve is additionally included.

[0019] The adjustable pressure relief valve is connected to the first two-position four-way valve and is configured to release residual gas from the helium gas pipelines.

[0020] Optionally, in the off-state working state:- the power supply is in the off-state state;- each of the first helium gas pipeline and the second helium gas pipeline is in the off-state; and- the first two-position four-way valve is adjusted so as to bring the cold head to the off-state working state, and the second two-position four-way valve is adjusted so as to bring the compressor to the pressure equalization state.

[0021] Optional, the following is additionally included:

[0022] - The adjustable pressure relief valve initiates pressure relief when the opening pressure of the adjustable pressure relief valve is reached, and automatically closes after pressure relief is complete.

[0023] Optionally, in the reconnection state:- the power supply is in the power-on state;- each of the first helium gas pipeline and the second helium gas pipeline is in a communicating state; and the first and second four-way position valves are adjusted so as to bring the cooling head into the reconnection state.

[0024] Optional, additionally enable the maintenance status.

[0025] The maintenance status includes the onboard maintenance status, the ground maintenance status, and the adjustable pressure relief valve setting status. The onboard maintenance status refers to the part where the cooling head is located, and the ground maintenance status refers to the part where the compressor is located.

[0026] Optionally, the following is enabled:

[0027] - In the on-board maintenance state, the first second position four-way valve is adjusted to bring the cooling head to the off-line working state, and the first needle valve is opened to empty the helium gas pipelines on the on-board part, and then closed;

[0028] -In the maintenance state of the ground part, the second two-position four-way valve is adjusted to bring the compressor to a state of equal pressure, and the second needle valve is opened to empty the helium gas pipelines of the ground part, and then closed;

[0029] -In the state of setting the adjustable pressure relief valve, the first two-position four-way valve is adjusted so as to bring the cooling head to the off-working state, and the adjustable pressure relief valve is adjusted while observing the first pressure gauge until the first pressure gauge indicates the required set pressure.

[0030] As can be seen from the above solution, the system for disconnecting a superconducting magnet from a refrigeration unit according to the present application includes a set of helium gas pipes, a cold head, a set of self-sealing connectors, a set of two-position four-way valves, a compressor, and a power source for supplying electricity to the compressor. In the present application, by connecting the compressor and the cold head through a set of helium gas pipes, using helium gas as a medium in contact with the thermal interaction region, and providing self-sealing connectors in the parts of the helium gas pipes that need to be connected and disconnected, it is possible to prevent the formation of cold in the thermal interaction region and other problems, significantly reducing the time required for disconnecting and reconnecting the system.In addition, no foreign gas is introduced during the entire process of disconnection and reconnection, thereby increasing the reliability of the system for disconnecting the superconducting magnet from the refrigeration unit. BRIEF DESCRIPTION OF DRAWINGS.

[0031] To more clearly illustrate embodiments of the invention or technical solutions in conventional technology, the following briefly describes the drawings, which are referred to to describe embodiments of the invention or conventional technology. Obviously, the drawings in the following description represent only some examples of the present invention, and for those skilled in the art, other drawings can be derived from these drawings without any creative effort.

[0032] Fig. 1 is a diagram showing the structure of a system for detaching a superconducting magnet from a refrigeration unit according to the present invention; and

[0033] Fig. 2 is a diagram showing an example of the structure of a system for detaching a superconducting magnet from a refrigeration unit according to the present invention.

[0034] Reference numbers are listed as follows: 1. first helium gas pipeline; 2. second helium gas pipeline; 3. cold head outlet pipe; 4. cold head inlet pipe; 5. compressor return pipe; 6. compressor outlet pipe; 7. self-sealing connector; 8. first two-position four-way valve; 9. second two-position four-way valve; 10. first ball valve; 11. second ball valve; 12. first pressure gauge; 13. second pressure gauge; 14. first needle valve; 15. second needle valve; 16. adjustable pressure relief valve; 17. power supply.DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION

[0035] In the following, the technical solutions according to the embodiments of the present application will be clearly and completely described with reference to the accompanying drawings through the embodiments of the present application. It is obvious that the described embodiments of the invention represent only a part of the embodiments of the invention according to the present application, and not all the embodiments of the invention. All other embodiments of the invention obtained by persons skilled in the art based on the embodiments of the invention in the present application without creative efforts fall within the scope of protection of the present application.

[0036] As used herein, the term "include" and variations thereof are inclusive and mean "including, but not limited to." The term "based on" means "based at least in part on." The term "an embodiment of the invention" means "at least one embodiment of the invention," the term "another embodiment of the invention" means "at least one other embodiment of the invention," and the term "some embodiments of the invention" means "at least some embodiments of the invention." Other terms are defined in the description below.

[0037] It should be noted that the terms "first" and "second", etc., mentioned in this application are used only to distinguish between various devices, modules or units, and not to limit the order or interdependence of the functions performed by the devices, modules or units.

[0038] It should be noted that the terms "one" and "several" mentioned in this application are illustrative and not limiting and should be understood as "one or more" by those skilled in the art unless clearly indicated otherwise in the context.

[0039] A superconducting magnet is an electromagnet made using superconducting coils. It can conduct electric current without electrical resistance or magnetic loss at extremely low temperatures and generate a strong magnetic field around it. Below its critical temperature, a superconducting magnet maintains superconducting ability. The superconducting magnet includes a high-temperature superconducting magnet, which is made using coils wound on a high-temperature superconducting strip. It can generate a strong magnetic field when power is supplied and is a critical core component of a maglev train. Relevant tests, such as electrodynamic suspension testing, traction testing, and car speed profile testing, should be conducted at the prototype stage.

[0040] In scale-up magnetic levitation testing, the scale-up magnetic levitation test car serves as a minimal system, powered by batteries. However, the onboard power supply cannot meet the power consumption requirements of the cryogenic refrigeration system for the superconducting magnet, i.e., it cannot meet the significant power consumption needs. Therefore, in the known technology, a ground power supply is used to continuously supply electricity to the cryocooler for the superconducting magnets. Furthermore, the load capacity of the scale-up test car is limited, so the compressor and water chiller of the cryogenic refrigeration system cannot be installed on the car.In general, under traditional tests for superconducting magnets, neither the on-board power source nor the load capacity can meet the performance requirements of the superconducting magnet refrigeration system.

[0041] Considering the power supply and the load capacity, it is proposed to disconnect the superconducting magnet from the cryogenic refrigeration unit during the test and, after the test, reconnect the superconducting magnet to the cryogenic refrigeration unit to restore the state it was in before being disconnected.

[0042] During actual testing, after the superconducting magnet is disconnected from the cryogenic refrigeration system, the internal temperature of the superconducting material gradually increases. When it reaches the cooling temperature of the superconducting material, the superconducting magnet is demagnetized, preventing it from meeting the testing requirements of the test system. Additionally, the maximum operating time in the disconnected state must be considered for the superconducting magnet. During actual testing, when a traditional superconducting magnet testing device operates in the disconnected state, problems such as freezing may occur in the thermal interface area. Therefore, operations such as preventing freezing in the thermal interface area must be performed before reconnecting, which requires a certain amount of time.The longer the time spent disconnecting and reconnecting to the cryocooler, the less available test time remains, which hinders both the reliability and effectiveness of superconducting magnet testing. During the traditional superconducting magnet testing process, which involves disconnecting and reconnecting to the refrigeration unit, foreign gas can enter during the reconnection, thereby affecting the superconducting magnet test result. In short, the traditional device for disconnecting the superconducting magnet from the refrigeration unit exhibits low reliability.

[0043] In order to solve the above problems, the present application proposes a system for detaching a superconducting magnet from a refrigeration unit.

[0044] Refer to Fig. 1, which is a diagram showing the structure of a system for detaching a superconducting magnet from a refrigeration unit according to the present application.

[0045] The system for separating a superconducting magnet from a refrigeration unit includes a set of helium gas pipes, a cold head, a set of self-sealing connectors, a set of two-position four-way valves, a compressor, and a power source 17 for supplying electricity to the compressor. Power source 17 can be located in the compressor or in the distribution cabinet.

[0046] For this solution, the inventor proposes dividing the system into an on-board portion and a ground portion. The cooling head and part of the helium gas pipelines remain on the train car, while the helium compressor, water chiller, and the remaining portion of the helium gas pipelines are located on the ground. By incorporating additional components into the helium gas pipelines, the superconducting magnet can be quickly and safely disconnected from the cryogenic refrigeration system (also known as a "cryocooler" or "refrigeration unit"). Dividing the system into an on-board portion and a ground portion can provide sufficient power to meet the energy consumption requirements of the cryogenic refrigeration system for the superconducting magnet, i.e., satisfy a significant energy consumption need. It should be noted that the cryogenic refrigeration system primarily provides a cryogenic environment for the superconducting magnets.

[0047] As shown in Fig. 1, the helium gas pipe set includes a first helium gas pipe 1 and a second helium gas pipe 2. The cooling head includes an outlet pipe 3 connected to a compressor return pipe 5 through the first helium gas pipe 1 and an inlet pipe 4 connected to a compressor outlet pipe 6 through the second helium gas pipe 2. It should be noted that the cooling head is a component of a refrigeration device and has a refrigeration end in the form of a copper block, which is connected to a structure to be cooled. The cooling head is connected to the helium gas pipe set. The helium gas in the helium gas pipes serves as a cooling medium to provide constant cryogenic cooling for the superconducting coils.Additionally, the cooling head is mounted in a superconducting magnet on the train car, and the compressor is installed on the ground. A set of helium gas pipes connects the ground and onboard components.

[0048] Separate self-sealing connectors 7 in the self-sealing connector set are installed in the cold head outlet pipe 3, the cold head inlet pipe 4, the compressor return pipe 5, and the compressor outlet pipe 6. The self-sealing connector is mainly used for connecting or disconnecting the superconducting magnet. After the helium gas pipe set is disconnected, the self-sealing connector 7 can automatically seal to prevent contamination of the high-purity helium source by outside air in the pipelines, thereby preventing the introduction of foreign gas that may affect the cooling efficiency.

[0049] Specifically, reference should be made to Fig. 2, which is a diagram showing an example of the structure of a system for disconnecting a superconducting magnet from a refrigeration unit according to the present application. The set of self-sealing connectors includes plug and socket connectors. The plug connector may include self-sealing connectors 7, 19, 21, 23, 25 and 27, and the corresponding socket connector may include self-sealing connectors 18, 20, 22, 24, 26 and 28. It can be understood that the self-sealing connectors in the set of self-sealing connectors are formed in pairs and can be interchanged.

[0050] The two-position four-way valve set includes a first two-position four-way valve 8 and a second two-position four-way valve 9. The first two-position four-way valve 8 is located on the side portion and is connected between the outlet pipe 3 and the inlet pipe 4 of the cooling head. It is primarily used to control the operating states of the cooling head, mainly including the disconnected operating state and the reconnected state. By adjusting the first two-position four-way valve 8, the cooling head can be controlled to be in the disconnected operating state or the reconnected state.

[0051] The second two-position four-way valve 9 is connected between the return pipe 5 and the compressor discharge pipe 6 and is mainly used to control the operating states of the compressor, mainly including the balanced pressure state and the normal state. By adjusting the second two-position four-way valve 9, the compressor can be controlled to be in the balanced pressure state or the normal state. It should be noted that the normal state is a state that enables the refrigeration operation. The high-pressure helium gas coming out of the compressor discharge pipe 6 is supplied to the cold head, and the low-pressure helium gas discharged from the cold head is returned to the compressor through the compressor return pipe 5.During this process, helium gas circulates as a cooling medium in the helium gas lines, removing heat from the cold end of the cold head.

[0052] The system for disconnecting the superconducting magnet from the refrigeration unit further includes a set of ball valves, a set of pressure gauges, a set of needle valves and an adjustable pressure relief valve 16.

[0053] The ball valve set is located only on the ground section. The ball valve set includes a first ball valve 10 and a second ball valve 11. The first ball valve 10 is located in the compressor return pipe 5 and is mainly used to block the compressor return pipe 5, such as during maintenance. The second ball valve 11 is located in the compressor outlet pipe 6 and is mainly used to block the compressor outlet pipe 6, such as during maintenance.

[0054] The pressure gauge set includes a first pressure gauge 12 and a second pressure gauge 13, and is mainly used to indicate the pressure in helium gas pipelines. The first pressure gauge 12 is connected to the first two-position four-way valve 8, and the second pressure gauge 13 is connected to the second two-position four-way valve 9. It should be noted that when the compressor is operating normally, the pressure difference between the return pipe 5 and the compressor outlet pipe 6 varies. When the compressor operates in a state of pressure equilibrium, gas does not flow through the return pipe 5 and the compressor outlet pipe 6, and the second pressure gauge 13 provides a stable reading.

[0055] The needle valve set includes a first needle valve 14 and a second needle valve 15, and is mainly used to relieve pressure during maintenance. The first needle valve 14 is connected to a first two-position four-way valve 8, and the second needle valve 15 is connected to a second two-position four-way valve 9. Specifically, the needle valves can be manually operated to relieve pressure.

[0056] Adjustable pressure relief valve 16 is primarily used to release residual gas generated in helium gas pipelines due to increased pressure caused by temperature rise. Adjustable pressure relief valve 16 is connected to the first two-position four-way valve 8. Specifically, the opening pressure of adjustable pressure relief valve 16 can be set to, for example, 2 bar lower than the maximum allowable pressure of the helium gas pipelines.

[0057] In general, a system for disconnecting a superconducting magnet from a refrigeration unit according to the present application includes a set of helium gas pipes, a cold head, a set of self-sealing connectors, a set of two-position four-way valves, a compressor, and a power source for supplying electricity to the compressor. In the present application, by connecting the compressor and the cold head through a set of helium gas pipes, using helium gas as a medium in contact with the thermal interaction region, and providing self-sealing connectors in the parts of the helium gas pipes that need to be connected or disconnected, it is possible to prevent freezing in the thermal interaction region and other problems, significantly reducing the time required for disconnecting and reconnecting the system.In addition, no foreign gas is introduced during the entire process of detaching and reconnecting, thereby increasing the reliability of the system for detaching the superconducting magnet from the refrigeration unit.

[0058] The above system for disconnecting the superconducting magnet from the refrigeration unit mainly includes three states: disconnected working state, reconnection state and maintenance state.

[0059] Adjusting the system for disconnecting the superconducting magnet from the refrigeration unit so that it is in a shut-off working state includes the following operations. 1) The power supply of the power source 17 for supplying electricity to the compressor is cut off. 2) The first two-position four-way valve 8 is manually adjusted so as to bring the cooling head to a shut-off working state. 3) The second two-position four-way valve 9 is manually adjusted so as to bring the compressor to a pressure-balanced state so as to equalize the internal pressures in the first helium gas pipeline 1 and the second helium gas pipeline 2, after which the second two-position four-way valve 9 automatically returns to the position in which it is in the normal state.4) The self-sealing connector 19 is disconnected from the self-sealing connector 20, and the self-sealing connector 25 is disconnected from the self-sealing connector 26 so as to complete the operations in the disconnected mode.

[0060] In general terms, in the power-off state, the power supply 17 is in the power-off state; each of the first helium gas pipeline 1 and the second helium gas pipeline 2 is in the power-off state; the cold head is in the power-off working state; and the compressor is in the pressure equalization state.

[0061] It should be noted that in the off state, the residual gas pressure in the helium gas pipelines gradually increases with increasing temperature. When the pressure reaches the opening pressure of the adjustable pressure relief valve 16, the adjustable pressure relief valve 16 opens to relieve the pressure in the pipelines and automatically closes after the pressure relief is complete. By providing the adjustable pressure relief valve 16, damage to the helium gas pipelines can be prevented and their service life can be extended.

[0062] Adjusting the system for disconnecting the superconducting magnet from the refrigeration unit so that it is in a reconnecting state includes the following operations: 1) The self-sealing connector 19 is connected to the self-sealing connector 20, and the self-sealing connector 25 is connected to the self-sealing connector 26. 2) The first two-position four-way valve 8 is manually adjusted so as to bring the cooling head to a reconnecting state. 3) The power source 17 is supplied with power so as to complete the reconnecting operations.

[0063] In general terms, in the reconnection state, the power supply 17 is in the energized state; each of the first helium gas pipeline 1 and the second helium gas pipeline 2 is in a communicating state; and the cooling head is in the reconnection state.

[0064] The maintenance status corresponding to the maintenance status mainly includes the maintenance status of the on-board part, the maintenance status of the ground part, and the setting status of the adjustable pressure relief valve.

[0065] The on-board maintenance status mainly refers to the state of the system for disconnecting the superconducting magnet from the refrigeration unit when performing maintenance on the component on the component containing the cold head. In this case, the system for disconnecting the superconducting magnet from the refrigeration unit operates as follows. 1) The first two-position four-way valve 8 operates to disable the cold head. 2) The first needle valve 14 remains open until the helium gas pipelines on the on-board component are emptied. At this stage, the needle valve is used to relieve pressure, since component replacement is impossible when the pressure in the helium gas pipelines is high.

[0066] The ground maintenance status mainly refers to the state of the system for disconnecting the superconducting magnet from the refrigeration unit when performing maintenance on the component on the part where the compressor is located. In this case, the system for disconnecting the superconducting magnet from the refrigeration unit operates as follows. 1) The second two-position four-way valve 98 operates to bring the compressor to a pressure-balanced state. 2) The second needle valve 15 remains open until the helium gas pipelines on the ground part are emptied.In the state of setting the adjustable pressure relief valve, the first two-position four-way valve 8 is adjusted so as to bring the cooling head to the switched-off working state, and the adjustable pressure relief valve 16 is adjusted while observing the first pressure gauge 12 until the first pressure gauge 12 indicates the required set pressure.

[0067] In general, the off-mode operation of the system for disconnecting a superconducting magnet from a refrigeration unit according to this application is simple, fast, and easily implemented. In actual applications, the disconnection or reconnection process can be completed in as little as 20 seconds, leaving sufficient time for railcar testing.

[0068] It should be noted that embodiments of the invention are described in this detailed description step by step, and each embodiment of the invention emphasizes differences from other embodiments of the invention. Identical or similar parts in the embodiments of the invention may be referenced to each other.

[0069] Finally, it should be noted that relative terms such as "first," "second," "third," and "fourth" are used herein only to distinguish one object or operation from another, and not to require or imply any actual relationship or order between those objects or operations. Furthermore, the terms "comprise," "include," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, object, or device that includes a sequence of factors includes not only the factors listed, but also includes other factors not expressly listed, or factors inherent in the process, method, object, or device. Without further limitation, a factor specified by the phrase "include one..." does not exclude the case in which another identical factor is provided in the process, method, object or device incorporating the described factor.

[0070] The above describes only preferred embodiments of the present application. It should be noted that improvements and modifications can be made by those skilled in the art without departing from the principles of the present application, and such improvements and modifications fall within the scope of protection of the present application.

Claims

1. A system for disconnecting a superconducting magnet from a refrigeration unit, comprising: set of tubes for gaseous helium; cooling head; set of self-sealing connectors; set of two-position four-way valves; compressor; and power source for supplying electricity to the compressor, wherein the set of pipes for gaseous helium comprises a first pipeline for gaseous helium and a second pipeline for gaseous helium; the cooling head comprises an outlet pipe connected to the compressor return pipe via a first pipeline for gaseous helium, and an inlet pipe connected to the compressor outlet pipe via a second pipeline for gaseous helium; and each of the outlet pipe of the cooling head, the inlet pipe of the cooling head, the compressor return pipe and the outlet pipe of the compressor is provided with a self-sealing connector for achieving the connection or disconnection of the pipelines for gaseous helium; and wherein the set of two-position four-way valves comprises a first two-position four-way valve and a second two-position four-way valve, wherein the first two-position four-way valve is connected between the outlet pipe and the inlet pipe of the cooling head and is configured to control the cooling head to be in a disconnected operating state or in a reconnected state, and the second two-position four-way valve is connected between the return pipe and the outlet pipe of the compressor and is configured to control the compressor to be in a state of balanced pressure or in a normal state.

2. The system according to item 1, further comprising a set of ball valves, wherein the set of ball valves comprises a first ball valve and a second ball valve, the first ball valve is located in the return pipe of the compressor and is configured to close the return pipe of the compressor in the maintenance state, and the second ball valve is located in the outlet pipe of the compressor and is configured to close the outlet pipe of the compressor in the maintenance state.

3. The system according to claim 1, further comprising a set of pressure gauges for indicating pressures in pipelines for gaseous helium, wherein the set of pressure gauges comprises a first pressure gauge connected to the first two-position four-way valve, and a second pressure gauge connected to the second two-position four-way valve.

4. The system of claim 3, further comprising a set of needle valves for relieving pressure, wherein the set of needle valves comprises a first needle valve connected to the first two-position four-way valve, and a second needle valve connected to the second two-position four-way valve.

5. The system of claim 4, further comprising an adjustable pressure relief valve, wherein the adjustable pressure relief valve is connected to the first two-position four-way valve and is configured to release residual gas from the helium gas pipelines.

6. The system according to paragraph 1, in which, in the switched-off operating state: the power supply is in the power-off state; each of the first helium gas pipeline and the second helium gas pipeline is in a shut-off state; and the first two-position four-way valve is configured to be adjustable to bring the cooling head to a switched-off operating state, and the second two-position four-way valve is configured to be adjustable to bring the compressor to a state of balanced pressure.

7. The system according to paragraph 5, in which: the adjustable pressure relief valve is configured to begin opening to relieve pressure upon reaching the opening pressure of the adjustable pressure relief valve, and to close automatically after the pressure relief is completed.

8. The system of claim 1, wherein, in the reconnected state: the power supply is in the power supply state; each of the first helium gas pipeline and the second helium gas pipeline is in a communicating state; and the first two-position four-way valve is adjustable to bring the cooling head into a reconnected state.

9. The system according to paragraph 5, additionally configured with the possibility of being in a maintenance state, wherein the maintenance state includes the maintenance state of the onboard portion, the maintenance state of the ground portion, and the setting state of the adjustable pressure relief valve, the onboard portion refers to the portion in which the cooling head is located, and the ground portion refers to the portion in which the compressor is located.

10. The system according to paragraph 9, in which: in the maintenance state of the side part, the first two-position four-way valve is configured to be adjustable to bring the cooling head to a disabled operating state, and the first needle valve is configured to be opened to empty the pipelines for gaseous helium of the side part, and then to be closed; in the ground portion maintenance state, the second two-position four-way valve is configured to be adjustable to bring the compressor to a state of balanced pressure, and the second needle valve is configured to be opened to empty the ground portion helium gas pipelines and then closed; and in the state of setting the adjustable pressure relief valve, the first two-position four-way valve is configured to be adjustable to bring the cooling head to a switched-off operating state, and the adjustable pressure relief valve is configured to be adjustable to monitor the first pressure gauge until the first pressure gauge indicates the required specified pressure.

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