CN117847831A - Adiabatic demagnetization refrigerating system capable of running without vibration and refrigerating method - Google Patents

Abstract

The invention provides an adiabatic demagnetization refrigerating system capable of running without vibration, and particularly relates to the technical field of low-temperature refrigeration. The heat conduction is controlled by arranging the thermal switch between the heat insulation demagnetization module and the precooling module. The heat-insulating demagnetizing module keeps a normal refrigerating mode when the heat switch is closed, and the precooling refrigerator is stopped simultaneously by switching off the heat switch, so that the system can be switched to a vibration-free refrigerating mode, mechanical vibration and electromagnetic interference are greatly reduced, high-end application requirements are met, the system can be switched between two refrigerating modes while the traditional heat-insulating demagnetizing module structure is kept, and the whole system is simple in structure and strong in operability.

Description

Adiabatic demagnetization refrigeration system capable of operating without vibration and refrigeration method

Technical Field

The present invention relates to the technical field of low-temperature refrigeration, and in particular to an adiabatic demagnetization refrigeration system and a refrigeration method capable of operating without vibration.

Background technique

With the development of cutting-edge scientific fields such as condensed matter physics, space measurement, and two-phase technology, the demand for ultra-low temperature refrigeration is increasing. Ultra-low temperature refrigeration technology is usually a refrigeration technology that can obtain a temperature below 1K and provide a certain amount of cooling. Currently, the commonly used ultra-low temperature refrigeration technologies mainly consist of adsorption refrigeration, dilution refrigeration, and adiabatic demagnetization refrigeration.

ADR, or adiabatic demagnetization refrigeration, is one of the earliest cryogenic refrigeration technologies. It has the advantages of high efficiency, independence from gravity and scarce helium-3 gas, making it the most promising cryogenic refrigeration technology in space applications. Adiabatic demagnetization refrigeration is based on the magnetocaloric effect of paramagnetic materials as the external magnetic field changes. Its basic structure includes a magnetocaloric module, a magnet, a thermal switch, a heat sink and a cold head. The ideal ADR performs a reverse Carnot cycle between the heat sink temperature and the refrigeration temperature through four processes: isothermal magnetization, adiabatic demagnetization, isothermal demagnetization and adiabatic magnetization. The magnetocaloric module is magnetized to a high temperature. When the temperature of the heat sink reaches a certain level, the thermal switch between the heat sink and the magnetothermal module is closed, the magnetothermal module is isothermally magnetized, and the magnetization heat is released to the heat sink until the upper limit of the target magnetic field is reached; the thermal switch between the heat sink and the magnetothermal module is disconnected, the magnetothermal module is adiabatically demagnetized and cooled to the cooling temperature, and under the heat load state, the demagnetization rate is controlled so that the magnetothermal module is isothermally demagnetized and generates cold to maintain the constant heat load temperature; when the magnetic field temperature drops to the lower limit of the target magnetic field, the thermal switch is kept disconnected so that the magnetothermal module is magnetized and regenerated under adiabatic conditions, and the above steps are repeated after the temperature is raised to the heat sink temperature. However, in some practical applications, a strictly quiet ultra-low temperature environment is required. For example, modern microscopes with spatial resolutions of nanometers or even picometers are extremely sensitive to external vibrations, and the compressor unit and cold head of a mechanical 4K refrigerator will produce large vibrations.

Summary of the invention

In order to solve the problem of vibration of the refrigeration unit during refrigeration, the present invention provides an adiabatic demagnetization refrigeration system and a refrigeration method that can operate without vibration.

The present invention is achieved through the following technical solutions:

The present invention proposes an adiabatic demagnetization refrigeration system capable of operating without vibration, comprising an adiabatic demagnetization module, a frame module and a precooling module, wherein:

The frame module includes a secondary cold shield sleeved on the outside of the adiabatic demagnetization module;

The adiabatic demagnetization module includes a magnetocaloric module, a load is connected to the bottom of the magnetocaloric module, and the magnetocaloric module is connected to a heat sink via a second thermal switch;

The upper and lower sides of the magnetocaloric module are connected to the suspension structure, the outer edge of the suspension structure is fixed to the upper and lower end surfaces of the magnetic shield, the magnetocaloric module is fixed in the middle of the annular superconducting magnet through the suspension structure, and the magnetocaloric module is not in contact with the superconducting magnet;

The adiabatic demagnetization module includes the magnetic shield, and one side of the top of the magnetic shield is connected to the heat sink through a copper rod;

A first thermal switch is provided on one side of the top of the heat sink, a secondary cold plate is also provided on the top of the secondary cold screen, the secondary cold plate is fixedly connected to the secondary cold screen, the heat sink is connected to the secondary cold plate via the first thermal switch, and the heat sink is fixed to the secondary cold plate via a low thermal conductivity support column;

The pre-cooling module is located on the top of the secondary cold plate and is connected to the secondary cold plate.

Furthermore, it also includes a primary cold screen and a primary cold plate, wherein the primary cold screen is sleeved on the outside of the secondary cold screen, and the primary cold screen is fixedly connected to the primary cold plate.

Furthermore, the bottom of the first-stage cold plate is fixedly connected to the top of the second-stage cold plate via a low thermal conductivity support column.

Furthermore, a secondary cold head is provided on one side of the bottom of the first-level cold plate, the top side of the secondary cold head is connected to the first-level cold plate, a flexible connector is provided on one side of the bottom of the secondary cold head, and the bottom of the secondary cold head is fixedly connected to the secondary cold plate through the flexible connector.

Furthermore, it also includes a vacuum cover and a sealing disk. The vacuum cover is sleeved on the outer side of the primary cold screen, and the vacuum cover is fixedly connected to the sealing disk.

Furthermore, the bottom of the sealing plate is fixedly connected to the primary cold plate via a low thermal conductivity support column.

Furthermore, a first-level cold head is provided at the bottom of the sealing disk, and the first-level cold head is located on the bottom of the sealing disk close to the second-level cold head. The top of the first-level cold head is connected to the sealing disk, and the bottom of the first-level cold head is connected to the first-level cold disk.

Furthermore, it also includes a pre-cooling refrigerator, the room temperature part of the pre-cooling refrigerator is located on the side of the sealing disk close to the first-level cold head, and the room temperature part of the pre-cooling refrigerator is connected to the sealing disk.

Furthermore, a shock-absorbing bellows is provided between the pre-cooling refrigerator and the vacuum cover.

Furthermore, a refrigeration method of an adiabatic demagnetization refrigeration system capable of operating without vibration includes a normal refrigeration mode and a vibration-free refrigeration mode, wherein the normal refrigeration mode includes the following steps:

The precooling refrigerator is started to perform cooling, the first thermal switch and the second thermal switch are closed, and the adiabatic demagnetization module is precooled through the precooling module;

After precooling to the heat sink temperature, the adiabatic demagnetization module operates, the magnetocaloric module is magnetized and cooled at the same time, and after reaching the target magnetic field, the second thermal switch is disconnected, followed by adiabatic demagnetization, isothermal demagnetization refrigeration, adiabatic magnetization, and then the second thermal switch is closed for isothermal magnetization to enter periodic refrigeration. In this mode, the precooling refrigerator is always in operation, and the first thermal switch is always in the closed state, which is the normal refrigeration mode;

The vibration-free refrigeration mode comprises the following steps:

The precooling refrigerator is started to perform cooling, the first thermal switch and the second thermal switch are closed, and the adiabatic demagnetization module is precooled through the precooling module;

After precooling to the heat sink temperature, the adiabatic demagnetization module operates, the magnetocaloric module is magnetized and cooled at the same time, and after reaching the target magnetic field, the second thermal switch and the first thermal switch are disconnected, and the precooling refrigerator stops running at the same time. The precooling module and the adiabatic demagnetization module are in a heat transfer disconnection state, and the magnetocaloric module performs adiabatic demagnetization and isothermal demagnetization refrigeration. In this mode, the precooling refrigerator is always in a stopped state, and the first thermal switch is always in a disconnected state, which is a vibration-free refrigeration mode;

The pre-cooling refrigerator restarts to cool, closes the first thermal switch and the second thermal switch, and the adiabatic demagnetization module operates. The magnetocaloric module is magnetized and cooled at the same time. After reaching the target magnetic field, the second thermal switch and the first thermal switch are disconnected, and the pre-cooling refrigerator stops running at the same time, starting a new round of vibration-free cooling mode.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a structural diagram of an adiabatic demagnetization refrigeration system capable of operating without vibration according to the present invention;

FIG2 is a structural diagram of a conventional adiabatic demagnetization refrigeration system;

In the figure, an adiabatic demagnetization module 1, a magnetocaloric module 11, a load 12, a second thermal switch 13, a heat sink 14, a suspension structure 15, a magnetic shield 16, a superconducting magnet 17, a high thermal conductivity copper rod 18, a frame module 2, a secondary cold screen 21, a secondary cold plate 22, a primary cold plate 23, a primary cold screen 24, a vacuum cover 25, a sealing plate 26, a low thermal conductivity support column 27, a pre-cooling module 3, a pre-cooling refrigerator 31, a primary cold head 32, a secondary cold head 33, a flexible connector 34, and a first thermal switch 4.

The purpose, features and advantages of the present invention will be further described with reference to the accompanying drawings in conjunction with the embodiments.

Detailed ways

In order to more clearly and completely illustrate the technical solution of the present invention, the present invention is further described below in conjunction with the accompanying drawings.

Please refer to FIG. 1-FIG. 2, the present invention proposes an adiabatic demagnetization refrigeration system capable of operating without vibration, comprising an adiabatic demagnetization module 1, a frame module 2 and a precooling module 3, wherein:

The frame module 2 includes a secondary cold shield 21 which is sleeved on the outside of the adiabatic demagnetization module 1;

The adiabatic demagnetization module 1 includes a magnetocaloric module 11 , a load 12 is connected to the bottom of the magnetocaloric module 11 , and the magnetocaloric module 11 is connected to a heat sink 14 via a second thermal switch 13 .

The upper and lower sides of the magnetocaloric module 11 are connected to the suspension structure 15, the outer edge of the suspension structure 15 is fixed to the upper and lower end surfaces of the magnetic shield 16, and the magnetocaloric module 11 is fixed in the middle of the annular superconducting magnet 17 through the suspension structure 15, and the magnetocaloric module 11 is not in contact with the superconducting magnet 17;

The adiabatic demagnetization module 1 includes the magnetic shield 16, and one side of the top of the magnetic shield 16 is connected to the heat sink 14 through a high thermal conductivity copper rod 18;

A first thermal switch 4 is provided on one side of the top of the heat sink 14, a secondary cold shield 21 is fixed to the secondary cold plate 22 on the top, the heat sink 14 is connected to the secondary cold plate 22 through the first thermal switch 4, and the heat sink 14 is fixed to the secondary cold plate 22 through a low thermal conductivity support column 27;

The pre-cooling module 3 is located on the top of the secondary cold plate 22 and is connected to the secondary cold plate 22 .

Specifically, the second thermal switch 13 and the first thermal switch 4 are used to control the conduction and disconnection of heat transfer. The precooling module 3 performs cooling, closes the first thermal switch 4 and the second thermal switch 13, and precools the adiabatic demagnetization module 1 through the precooling module 3. After precooling to the required temperature of the heat sink 14, the adiabatic demagnetization module 1 operates, and the magnetocaloric module 11 is magnetized and cooled at the same time. After reaching the target magnetic field, the adiabatic demagnetization process begins.

In the normal cooling mode, the precooling refrigerator 31 is always kept in operation, and the first thermal switch 4 is always in a closed state. In the adiabatic demagnetization process, when the temperature of the magnetocaloric module 11 drops to the cooling temperature, the second thermal switch 13 is kept disconnected, and the isothermal demagnetization cooling process is entered, and a certain load 12 is applied. When the isothermal demagnetization reaches zero magnetic field, the first cooling is completed, and the second thermal switch 13 is kept disconnected, and the adiabatic magnetization process is entered. When the magnetocaloric module 11 is heated to a temperature slightly higher than the temperature of the heat sink 14, the second thermal switch 13 is closed, the magnetocaloric module 11 isothermally magnetized, generates magnetization heat, and releases the magnetization heat to the heat sink 14 through the second thermal switch 13; when the magnetocaloric module 11 is magnetized to the maximum magnetic field, it enters a periodic cooling process;

In some practical applications, a strictly quiet and extremely low temperature environment is required, and the precooling refrigerator 31 needs to be stopped to perform vibration-free cooling. If no thermal switch is provided between the precooling module 3 and the adiabatic demagnetization module 1 for connection, since the precooling module 3 contains many metal parts, the precooling module 3 can be a thermal conductor at this time. A large amount of heat leakage from the high temperature area causes the heat sink 14 to heat up rapidly, and the superconducting magnet 17 will not be able to work normally due to quenching, thereby failing to perform adiabatic demagnetization cooling;

The present application adds a first thermal switch 4 connection between the precooling module 3 and the adiabatic demagnetization module 1, the precooling refrigerator 31 stops running, and the first thermal switch 4 is disconnected to cut off the heat transfer between the precooling module 3 and the adiabatic demagnetization module 1, so that the adiabatic demagnetization module 1 can maintain the load 12 at the refrigeration temperature for a long time and provide a vibration-free environment. At the same time, high-power components such as the compressor and rotary valve in the precooling refrigerator stop running, which greatly reduces electromagnetic interference.

The precooling module 3 performs cooling, closes the first thermal switch 4 and the second thermal switch 13, and precools the adiabatic demagnetization module 1 through the precooling module 3. After precooling to the required temperature of the heat sink 14, the adiabatic demagnetization module 1 operates, and the magnetocaloric module 11 is magnetized and cooled at the same time. After reaching the target magnetic field, it enters the vibration-free cooling mode.

In the vibration-free operation mode, the precooling refrigerator 31 is always stopped, and the first thermal switch 4 is always in the disconnected state. When the magnetocaloric module 11 is cooled and magnetized to the target magnetic field, the second thermal switch 13 and the first thermal switch 4 are disconnected, and the precooling refrigerator 31 stops running at the same time. The precooling module 3 and the adiabatic demagnetization module 1 are in the heat transfer disconnected state, and the magnetocaloric module 11 performs adiabatic demagnetization; when the temperature of the magnetocaloric module 11 drops to the refrigeration temperature, the second thermal switch 13 is kept disconnected, and the isothermal demagnetization refrigeration process is entered, and vibration-free refrigeration is performed on the load 12; when the isothermal demagnetization reaches zero magnetic field, the precooling refrigerator 31 restarts to perform refrigeration, closes the first thermal switch 4 and the second thermal switch 13, and the adiabatic demagnetization module 1 operates, and the magnetocaloric module 11 is magnetized and cooled at the same time. After reaching the target magnetic field, the second thermal switch 13 and the first thermal switch 4 are disconnected, and the precooling refrigerator 31 stops running at the same time, and a new round of vibration-free refrigeration mode is started.

In one embodiment, Figure 2 is a structural design of a traditional adiabatic demagnetization refrigeration system. The present application adds a first thermal switch 4 between the pre-cooling module 3 and the adiabatic demagnetization module 1. The entire system has a simple structure and strong operability, meeting more stringent ultra-low temperature refrigeration requirements. At the same time, the first thermal switch 4 and the second thermal switch 13 can also accelerate the cooling rate.

Furthermore, it also includes a primary cold screen 24 and a primary cold plate 23, the primary cold screen 24 is sleeved on the outside of the secondary cold screen 21, and the primary cold screen 24 is fixedly connected to the primary cold plate 23;

The bottom of the primary cold plate 23 is fixedly connected to the top of the secondary cold plate 22 via a low thermal conductivity support column 27;

A secondary cold head 33 is provided on one side of the bottom of the primary cold plate 23, and a top side of the secondary cold head 33 is fixedly connected to the primary cold plate 23. A flexible connector 34 is provided on one side of the bottom of the secondary cold head 33, and the bottom of the secondary cold head 33 is connected to the secondary cold plate 22 through the flexible connector 34.

Specifically, the flexible connector 34 can reduce vibration. The flexible connector 34 is made of high-purity copper foil or copper braid. The bottom of the second cold head and the secondary cold plate 22 are flexibly thermally connected through the flexible connector 34. The primary cold plate 23 and the secondary cold plate 22 are both made of oxygen-free high-purity copper. The surface of the secondary cold plate 22 is gold-plated. The gold plating treatment is used to strengthen the thermal contact of the 4K temperature zone components and prevent oxidation. The primary cold screen 24 and the secondary cold screen 21 are made of polished aluminum and are wrapped with multiple layers of thermal insulation materials to reduce radiation heat leakage. The low thermal conductivity support column 27 supports and connects the primary cold plate 23, the secondary cold plate 22 and the heat sink 11. The low thermal conductivity support column 27 here is supported by a thin-walled stainless steel tube.

Furthermore, it also includes a vacuum cover 25 and a sealing disk 26 . The vacuum cover 25 is sleeved on the outer side of the primary cold shield 24 , and the vacuum cover 25 is fixedly connected to the sealing disk 26 .

The bottom of the sealing plate 26 is fixedly connected to the primary cold plate 23 through the low thermal conductivity support column 4. A primary cold head 32 is also provided at the bottom of the sealing plate 26. The primary cold head 32 is located at the bottom of the sealing plate 26 near the secondary cold head 33. The top of the primary cold head 32 is connected to the sealing plate 26, and the bottom of the primary cold head 32 is connected to the primary cold plate 23.

Specifically, the supporting column 27 between the sealing disk 26 and the primary cold disk 23 is made of a glass fiber material with high strength and low thermal conductivity. The vacuum cover 25 and the sealing disk 26 are sleeved on the outside of the primary cold screen 24. The vacuum cover 25 and the sealing disk 26 are used to isolate the outside and the primary cold screen 24, and reduce heat transfer through vacuum treatment to prevent external heat energy from being transferred to the inside of the vacuum cover 25.

Furthermore, it also includes a pre-cooling refrigerator 31, the room temperature part of the pre-cooling refrigerator 31 is located on the side of the sealing disk close to the primary cold head, and the room temperature part of the pre-cooling refrigerator is connected to the sealing disk.

A shock-absorbing bellows is provided between the pre-cooling refrigerator 31 and the vacuum cover 25 .

Specifically, the pre-cooling refrigerator 31 is used for pre-cooling, and a two-stage G-M type pulse tube pre-cooling refrigerator 31 is adopted. The pre-cooling refrigerator 31 is used to provide cooling capacity. The vibration-damping bellows can reduce the vibration of the pre-cooling refrigerator 31. The cooling capacity transmitted by the pre-cooling refrigerator 31 passes through the first-stage cold head 32, the first-stage cold plate 23, the second-stage cold head 33, the flexible connector 34, and the second-stage cold plate 22 in sequence, and is finally transmitted to the adiabatic demagnetization module through the first thermal switch 4.

Further, it includes a normal cooling mode and a vibration-free cooling mode, wherein the normal cooling mode includes the following steps:

The precooling refrigerator 31 is started to perform cooling, the first thermal switch 4 and the second thermal switch 13 are closed, and the adiabatic demagnetization module 1 is precooled through the precooling module 3;

After precooling to the temperature of the heat sink 14, the adiabatic demagnetization module 1 operates, the magnetocaloric module 11 is magnetized and cooled at the same time, and after reaching the target magnetic field, the second thermal switch 13 is disconnected, followed by adiabatic demagnetization, isothermal demagnetization refrigeration, adiabatic magnetization, and then the second thermal switch 13 is closed, isothermal magnetization is performed, and periodic refrigeration is entered. In this mode, the precooling refrigerator 31 is always kept in operation, and the first thermal switch 4 is always in a closed state, which is a normal refrigeration mode;

The vibration-free cooling mode includes the following steps:

The precooling refrigerator 31 is started to perform cooling, the first thermal switch 4 and the second thermal switch 13 are closed, and the adiabatic demagnetization module 1 is precooled through the precooling module 3;

After precooling to the temperature of the heat sink 14, the adiabatic demagnetization module 1 operates, the magnetocaloric module 11 is magnetized and cooled at the same time, and after reaching the target magnetic field, the second thermal switch 13 and the first thermal switch 4 are disconnected, and the precooling refrigerator 31 stops running at the same time, the precooling module 3 and the adiabatic demagnetization module 1 are in a heat transfer disconnection state, and the magnetocaloric module 11 performs adiabatic demagnetization and isothermal demagnetization refrigeration. In this mode, the precooling refrigerator 31 is always in a stopped state, and the first thermal switch 4 is always in a disconnected state, which is a vibration-free refrigeration mode;

The pre-cooling refrigerator 31 restarts to cool, closes the first thermal switch 4 and the second thermal switch 13, and the adiabatic demagnetization module 1 operates. The magnetocaloric module 11 is magnetized and cooled at the same time. After reaching the target magnetic field, the second thermal switch 13 and the first thermal switch 4 are disconnected, and the pre-cooling refrigerator 31 stops running at the same time, starting a new round of vibration-free cooling mode.

Specifically, first, the vacuum cover 25 is evacuated to a pressure lower than 0.1Pa, the pre-cooling refrigerator 31 is started, and the first thermal switch 4 and the second thermal switch 13 are closed. The pre-cooling module 3 pre-cools the adiabatic demagnetization module 1, the first-stage cold head 32 is cooled to about 30K, the second-stage cold head 33 is cooled to about 4K, and the adiabatic demagnetization module is pre-cooled to about 4K at the same time; the adiabatic demagnetization module 1 is operated, the magnetocaloric module 11 is magnetized and cooled at the same time, and after reaching the target magnetic field, the adiabatic demagnetization process is entered.

In the normal cooling mode, the precooling refrigerator 31 is always kept in operation, and the first thermal switch 4 is always in a closed state. In the adiabatic demagnetization process, when the temperature of the magnetocaloric module 11 drops to the cooling temperature, the second thermal switch 13 is kept disconnected, and the isothermal demagnetization cooling process is entered, and a certain load 12 is applied. When the isothermal demagnetization reaches zero magnetic field, the first cooling is completed, and the second thermal switch 13 is kept disconnected, and the adiabatic magnetization process is entered. When the magnetocaloric module 11 is heated to a temperature slightly higher than the temperature of the heat sink 14, the second thermal switch 13 is closed, the magnetocaloric module 11 isothermally magnetized, generates magnetization heat, and releases the magnetization heat to the heat sink 14 through the second thermal switch 13; when the magnetocaloric module 11 is magnetized to the maximum magnetic field, it enters the normal periodic cooling process;

In the vibration-free operation mode, the precooling refrigerator 31 is always stopped, and the first thermal switch 4 is always in the disconnected state. When the magnetocaloric module 11 is cooled and magnetized to the target magnetic field, the second thermal switch 13 and the first thermal switch 4 are disconnected, and the precooling refrigerator 31 stops running at the same time. The precooling module 3 and the adiabatic demagnetization module 1 are in the heat transfer disconnected state, and the magnetocaloric module 11 performs adiabatic demagnetization; when the temperature of the magnetocaloric module 11 drops to the refrigeration temperature, the second thermal switch 13 is kept disconnected, and the isothermal demagnetization refrigeration process is entered, and vibration-free refrigeration is performed on the load 12; when the isothermal demagnetization reaches zero magnetic field, the precooling refrigerator 31 restarts to perform refrigeration, closes the first thermal switch 4 and the second thermal switch 13, and the adiabatic demagnetization module 1 operates, and the magnetocaloric module 11 is magnetized and cooled at the same time. After reaching the target magnetic field, the second thermal switch 13 and the first thermal switch 4 are disconnected, and the precooling refrigerator 31 stops running at the same time, and a new round of vibration-free refrigeration mode is started.

In one embodiment, the type of pre-cooling refrigerator and the refrigeration temperature range of the pre-cooling refrigerator can be selected according to actual conditions. The present invention is a single-stage adiabatic demagnetization system, and multi-stage adiabatic demagnetization, multiple refrigeration temperatures and multiple heat sink temperatures can be set according to actual needs. The magnetocaloric material of the adiabatic demagnetization module 1 can also be selected according to actual needs. In the single-stage adiabatic demagnetization system, it can be gadolinium gallium garnet or lithium gadolinium fluoride, etc. In the multi-stage adiabatic demagnetization system, the lower temperature level can be chromium potassium alum or iron ammonium alum, etc., which can be selected according to actual needs. The first thermal switch 4 and the second thermal switch 13 in the present application can also be selected according to actual refrigeration needs, such as air gap thermal switch, superconducting thermal switch, magnetoresistive thermal switch and mechanical thermal switch, etc. Similarly, the material types of other components of the present invention can also be selected according to actual conditions and needs.

Of course, the present invention may have many other implementations. Based on this implementation, other implementations obtained by ordinary technicians in this field without any creative work are all within the scope of protection of the present invention.

Claims (10)

1. An adiabatic demagnetization refrigeration system capable of operating without vibration, characterized in that it comprises an adiabatic demagnetization module, a frame module and a precooling module, wherein: The frame module includes a secondary cold shield sleeved on the outside of the adiabatic demagnetization module; The adiabatic demagnetization module comprises a magnetocaloric module, a load is connected to the bottom of the magnetocaloric module, and the magnetocaloric module is connected to a heat sink via a second thermal switch. The upper and lower sides of the magnetocaloric module are connected to the suspension structure, the outer edge of the suspension structure is fixed to the upper and lower end surfaces of the magnetic shield, the magnetocaloric module is fixed in the middle of the annular superconducting magnet through the suspension structure, and the magnetocaloric module is not in contact with the superconducting magnet; The adiabatic demagnetization module includes the magnetic shield, and one side of the top of the magnetic shield is connected to the heat sink through a high thermal conductivity copper rod; A first thermal switch is provided on one side of the top of the heat sink, a secondary cold plate is also provided on the top of the secondary cold screen, the secondary cold plate is fixedly connected to the secondary cold screen, the heat sink is connected to the secondary cold plate via the first thermal switch, and the heat sink is fixed to the secondary cold plate via a low thermal conductivity support column; The pre-cooling module is located on the top of the secondary cold plate and is connected to the secondary cold plate. 2. The adiabatic demagnetization refrigeration system capable of vibration-free operation according to claim 1 is characterized in that it also includes a primary cold screen and a primary cold plate, the primary cold screen is sleeved on the outside of the secondary cold screen, and the primary cold screen is fixedly connected to the primary cold plate. 3. The adiabatic demagnetization refrigeration system capable of vibration-free operation according to claim 2, characterized in that the bottom of the primary cold plate is fixedly connected to the top of the secondary cold plate via a low thermal conductivity support column. 4. The adiabatic demagnetization refrigeration system capable of vibration-free operation according to claim 3 is characterized in that a secondary cold head is provided on one side of the bottom of the primary cold plate, a top side of the secondary cold head is connected to the primary cold plate, a flexible connector is provided on one side of the bottom of the secondary cold head, and the bottom of the secondary cold head is fixedly connected to the secondary cold plate via the flexible connector. 5. The adiabatic demagnetization refrigeration system capable of vibration-free operation according to claim 4, further comprising a vacuum cover and a sealing disk, wherein the vacuum cover is sleeved on the outer side of the primary cold screen, and the vacuum cover is fixedly connected to the sealing disk. 6. The adiabatic demagnetization refrigeration system capable of vibration-free operation according to claim 5, characterized in that the bottom of the sealing disk is fixedly connected to the primary cold disk via a low thermal conductivity support column. 7. The adiabatic demagnetization refrigeration system capable of vibration-free operation according to claim 6, characterized in that a primary cold head is further provided at the bottom of the sealing disk, the primary cold head is located at the bottom of the sealing disk close to the secondary cold head, the top of the primary cold head is connected to the sealing disk, and the bottom of the primary cold head is connected to the primary cold disk. 8. The adiabatic demagnetization refrigeration system capable of vibration-free operation according to claim 7, further comprising a pre-cooling refrigerator, wherein the room temperature portion of the pre-cooling refrigerator is located on the side of the sealing disk close to the primary cold head, and the room temperature portion of the pre-cooling refrigerator is connected to the sealing disk. 9. The adiabatic demagnetization refrigeration system capable of vibration-free operation according to claim 8, characterized in that a shock-absorbing bellows is provided between the pre-cooling refrigerator and the vacuum cover. 10. A refrigeration method of the adiabatic demagnetization refrigeration system capable of vibration-free operation according to claims 1-9, characterized in that it comprises a normal refrigeration mode and a vibration-free refrigeration mode, wherein the normal refrigeration mode comprises the following steps: The precooling refrigerator is started to perform cooling, the first thermal switch and the second thermal switch are closed, and the adiabatic demagnetization module is precooled through the precooling module; After precooling to the heat sink temperature, the adiabatic demagnetization module operates, the magnetocaloric module is magnetized and cooled at the same time, and after reaching the target magnetic field, the second thermal switch is disconnected, followed by adiabatic demagnetization, isothermal demagnetization refrigeration, adiabatic magnetization, and then the second thermal switch is closed for isothermal magnetization to enter periodic refrigeration. In this mode, the precooling refrigerator is always in operation, and the first thermal switch is always in the closed state, which is the normal refrigeration mode; The vibration-free refrigeration mode comprises the following steps: The precooling refrigerator is started to perform cooling, the first thermal switch and the second thermal switch are closed, and the adiabatic demagnetization module is precooled through the precooling module; After precooling to the heat sink temperature, the adiabatic demagnetization module operates, the magnetocaloric module is magnetized and cooled at the same time, and after reaching the target magnetic field, the second thermal switch and the first thermal switch are disconnected, and the precooling refrigerator stops running at the same time. The precooling module and the adiabatic demagnetization module are in a heat transfer disconnection state, and the magnetocaloric module performs adiabatic demagnetization and isothermal demagnetization refrigeration. In this mode, the precooling refrigerator is always in a stopped state, and the first thermal switch is always in a disconnected state, which is a vibration-free refrigeration mode; The pre-cooling refrigerator restarts to cool, closes the first thermal switch and the second thermal switch, and the adiabatic demagnetization module operates. The magnetocaloric module is magnetized and cooled at the same time. After reaching the target magnetic field, the second thermal switch and the first thermal switch are disconnected, and the pre-cooling refrigerator stops running at the same time, starting a new round of vibration-free cooling mode.