A magnetic isolation type axial magnetic suspension bearing structure

Abstract

The application relates to the technical field of magnetic suspension bearing, in particular to a magnetic isolation type axial magnetic suspension bearing structure which comprises a load-bearing rotor body used for bearing high-speed rotation and axial load, an annular groove is arranged at the axial end of the load-bearing rotor body, a magnetic selection rotor assembly is arranged in the annular groove, and a magnetic selection stator assembly used for generating axial controllable electromagnetic attraction is arranged at the axial outer side of the load-bearing rotor body and corresponds to the magnetic selection rotor assembly. According to the application, the mechanical load-bearing function and the controlled magnetic conduction function are separated in material and structure, the load-bearing rotor body can adopt high-strength ferromagnetic material to ensure the safety of high-speed rotation, meanwhile, the axial magnetic component embedded in the end groove of the load-bearing rotor body is made of low-coercive-force soft magnetic material and specially bears the controlled magnetic conduction function, thus fundamentally solving the technical problem that a single material cannot simultaneously consider mechanical strength and soft magnetic performance, and realizing the unity of mechanical safety and electromagnetic control quality under high-speed heavy-load working conditions.

Description

Technical Field

[0001] This invention relates to the field of magnetic levitation bearing technology, and in particular to a magnetically shielded axial magnetic levitation bearing structure. Background Technology

[0002] Axial active magnetic levitation bearings typically consist of an axial stator, excitation coils, and a thrust disc integrated with or fixedly connected to the rotor. For heavy-load, high-speed, or high-inertia rotors, the bearing body must prioritize requirements for strength, fatigue resistance, and fracture safety. In engineering, high-strength ferromagnetic materials such as 40Cr, 42CrMo, and 35Cr2Ni4MoA are commonly used. However, these materials exhibit significant hysteresis, high coercivity, and low incremental permeability. When the rotor body or the thrust disc integrated with it is directly used as part of the controlled magnetic circuit, changes in excitation current are difficult to stably translate into corresponding changes in air gap flux and axial control force, resulting in unstable control force gain, asymmetrical forward and reverse responses, and operating point drift.

[0003] To address this, existing technologies attempt to add soft magnetic coverings to the rotor surface or to separate the thrust disk in order to partially isolate the controlled magnetic circuit from the high-strength load-bearing material. However, in these solutions, there is still a large area of ​​direct contact between the soft magnetic components and the load-bearing rotor. The control flux can still enter the load-bearing rotor through the contact surface to form a magnetic bypass, making it impossible for the controlled magnetic circuit to obtain a relatively independent closed path. Therefore, the influence of the high-strength load-bearing material on hysteresis and magnetization history cannot be effectively suppressed. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a magnetically isolated axial magnetic levitation bearing structure, which solves the technical problems of unstable control force gain and asymmetrical forward and reverse responses caused by the direct participation of high-strength ferromagnetic load-bearing rotor in the controlled magnetic circuit. It has the advantages of effectively isolating the control magnetic flux from the load-bearing rotor body and improving the stability of control force gain.

[0005] To solve the above-mentioned technical problems, the present invention provides the following technical solution: a magnetically shielded axial magnetic levitation bearing structure, comprising a load-bearing rotor body for bearing high-speed rotation and axial load, wherein an annular groove is formed at the axial end of the load-bearing rotor body, and a magnetic separator rotor assembly is disposed within the annular groove; a magnetic separator assembly for generating axially controllable electromagnetic attraction is disposed on the outer axial side of the load-bearing rotor body corresponding to the magnetic separator rotor assembly; the load-bearing rotor body is made of a first ferromagnetic material, with mechanical strength as the primary material selection criterion; and the axial magnetic actuation component is made of a second soft magnetic material, with low coercivity and high incremental permeability as the primary material selection criteria. By having the mechanical load-bearing function and the controlled magnetic actuation function respectively undertaken by the load-bearing rotor body and the axial magnetic actuation component, the mechanical load-bearing function and the controlled magnetic actuation function are respectively undertaken by the load-bearing rotor body and the axial magnetic actuation component. This allows for the independent selection of two materials according to their respective performance requirements, balancing high-speed mechanical safety and electromagnetic control quality. The magnetic separation rotor assembly includes an axial magnetic actuator made of a low-coercivity soft magnetic material and a magnetic isolation assembly disposed between the axial magnetic actuator and the load-bearing rotor body. The magnetic isolation assembly only covers the back and radial sides of the axial magnetic actuator to increase the magnetic resistance between the axial magnetic actuator and the load-bearing rotor body. The magnetic separation rotor assembly includes a soft magnetic stator body and excitation coil one and excitation coil two disposed on the soft magnetic stator body. The excitation directions of excitation coil one and excitation coil two are opposite and their ampere-turn amplitudes are equal, which is used to form a locally closed control magnetic circuit between the soft magnetic stator body, the axial working air gap and the axial magnetic actuator.

[0006] Preferably, the magnetic shielding component is an integrated magnetic shielding sleeve with a U-shaped, groove-shaped, or cup-shaped cross-section. The bottom of the integrated magnetic shielding sleeve covers the back of the axial magnetic actuating element, and the two sides of the integrated magnetic shielding sleeve cover the radial inner and radial outer sides of the axial magnetic actuating element, respectively. The integrated magnetic shielding sleeve can be made of austenitic stainless steel, titanium alloy, aluminum alloy, ceramic, polyetheretherketone, or fiber-reinforced composite material. When the magnetic shielding component is made of conductive metal material, it can be segmented circumferentially or have interrupted grooves to avoid forming a closed circumferential eddy current loop. The magnetic shielding component is mainly used to form a high magnetic resistance interface.

[0007] Preferably, the inner sidewall of the annular groove is provided with a mounting boss for mounting the magnetic shielding component and the axial magnetic actuating component. The mounting boss provides radial positioning for the magnetic shielding component and the axial magnetic actuating component, ensuring that the axial working air gap between the axial magnetic actuating component and the magnetic selector component is uniform.

[0008] Preferably, the mounting boss is provided with a fixing component for axially pressing the magnetic isolation component and the axial magnetic actuating component. The fixing component is a non-magnetic bolt, which is used to reliably transmit the axial electromagnetic attraction force from the axial magnetic actuating component to the load-bearing rotor body, and effectively limit the radial movement, axial disengagement and circumferential sliding of the axial magnetic actuating component at high operating speeds.

[0009] Preferably, the axial magnetic actuator is composed of multiple arc-shaped blocks arranged circumferentially, with non-magnetic intervals between each arc-shaped block. The axial magnetic actuator can also be a continuous ring-shaped component, in which case the magnetic flux distribution is continuous and the structure is simple, making it suitable for applications with small diameters or low rotational speeds.

[0010] Preferably, the excitation coil one and excitation coil two are coaxial ring coils arranged radially on the soft magnetic stator body. Excitation coil one and excitation coil two are connected in series and reversed. When the magnetic stator assembly uses more coils (such as three excitation coils), the inner and outer radial coils can be excited in the same direction, and the middle coil can be excited in the opposite direction. The ampere-turns of the middle coil can be equal to the sum of the ampere-turns of the two coils, which can still meet the ampere-turn balance condition.

[0011] Preferably, annular grooves are provided at both axial ends of the load-bearing rotor body, and magnetic selection rotor components are respectively arranged in each annular groove. Magnetic selection rotor components are respectively arranged on the two axial outer sides of the load-bearing rotor body to form a double-sided differential axial magnetic levitation support structure. In the double-sided differential structure, the upper and lower magnetic selection rotor components are controlled independently. The controller can combine static load-bearing commands and dynamic control commands to obtain scalar excitation commands on both sides. The coil groups on both sides distribute current according to their respective ampere-turn balance relationships, thereby realizing bidirectional high-precision axial position control.

[0012] Preferably, it also includes a controller, which is used to acquire the axial displacement signal of the load-bearing rotor body and generate a current command based on the axial displacement signal to keep the ampere-turn amplitude of excitation coil one and excitation coil two equal. The controller can correct the current distribution coefficient based on at least one of the signals of air gap flux, magnetic induction intensity, coil voltage or coil current to compensate for the asymmetry of coil parameters and local magnetic circuit.

[0013] By means of the above technical solution, the present invention provides a magnetically shielded axial magnetic levitation bearing structure, which has at least the following beneficial effects: 1. This invention separates the mechanical load-bearing function and the controlled magnetic conduction function in terms of materials and structure, so that the load-bearing rotor body can be made of high-strength ferromagnetic material to ensure high-speed rotation safety, while the axial magnetic action component made of low coercivity soft magnetic material embedded in the end groove is dedicated to the controlled magnetic conduction function. This fundamentally solves the technical problem that a single material cannot simultaneously take into account both mechanical strength and soft magnetic properties, and achieves the unity of mechanical safety and electromagnetic control quality under high-speed heavy-load conditions.

[0014] 2. By setting magnetic isolation components on the back and radial inner and outer sides of the axial magnetic actuating component, the present invention exposes the axial magnetic actuating component only to the axial acting surface of the magnetic selector component, which effectively increases the magnetic resistance between the axial magnetic actuating component and the load-bearing rotor body, suppresses the bypass path of the control magnetic flux from the non-working surface into the load-bearing rotor body, and confines the main control magnetic flux inside the low coercivity soft magnetic material, which can significantly reduce the adverse effects of the high-strength load-bearing rotor body hysteresis on axial control.

[0015] 3. By setting the excitation coils in the magnetic selector assembly to have opposite excitation directions and equal ampere-turn amplitudes, the present invention enables the formation of a partially closed control magnetic circuit between adjacent magnetic poles, the axial working air gap, and the axial magnetic actuator. This control magnetic circuit mainly passes through the axial magnetic actuator without passing through the load-bearing rotor body. At the same time, the axial attraction forces generated in each air gap region are superimposed in the same direction and do not cancel each other out. This can achieve effective isolation between the control magnetic flux and the load-bearing rotor body while ensuring sufficient electromagnetic attraction force.

[0016] 4. The axial magnetic actuator of the present invention can adopt a circumferential block structure to reduce circumferential eddy current loss and processing difficulty. The magnetic selector assembly can adopt an even-number configuration of two coils connected in series and reversed, or an odd-number configuration of three coils with ampere-turn balance, or a circumferential modular structure. It can also be expanded into a dual-sided differential structure to achieve bidirectional high-precision axial position control. The various flexible implementation methods enable the present invention to be widely adapted to different application scenarios such as flywheel energy storage, high-speed motors, compressors, and turbine machinery.

[0017] 5. The present invention generates a current command based on the axial displacement signal to keep the ampere-turn amplitude of each excitation coil equal. This enables each coil to always meet the ampere-turn balance condition when the current amplitude changes synchronously, thereby ensuring that the locally closed control magnetic circuit can be constrained to a predetermined path under any working condition and will not spread to the load-bearing rotor body. Attached Figure Description

[0018] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings: Figure 1 This is a front view of the overall structure of the present invention; Figure 2 This is a perspective view of the overall structure of the present invention; Figure 3 This is a schematic diagram of the magnetic selector assembly in this invention; Figure 4 This is a schematic diagram of the end of the load-bearing rotor body in this invention; Figure 5 This is a schematic diagram of the magnetic separation rotor assembly in this invention; Figure 6 This is a schematic diagram of the magnetic shielding component in this invention; Figure 7 This is a schematic diagram of the axial magnetic actuator in this invention; Figure 8 This is a partial cross-sectional schematic diagram under an even number of coils; Figure 9 This is a schematic diagram of a partial cross-section under an odd number of coils.

[0019] In the figure: 1. Load-bearing rotor body; 2. Magnetic selector assembly; 201. Soft magnetic stator body; 202. Excitation coil one; 203. Excitation coil two; 3. Magnetic selector rotor assembly; 301. Annular groove; 302. Mounting boss; 303. Magnetic isolation assembly; 304. Axial magnetic action component; 305. Fixing assembly. Detailed Implementation

[0020] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] Example 1 In existing axial active magnetic levitation bearings, the thrust disc or rotor yoke is typically integrally formed from the rotor body material, or made of the same material. When the rotor body uses high-strength ferromagnetic materials to meet the mechanical strength requirements under high-speed rotation and heavy-load conditions, these materials often suffer from problems such as high coercivity, low incremental permeability, and significant hysteresis. This makes it difficult to stably convert changes in excitation current into corresponding changes in air gap flux and axial electromagnetic force, resulting in control defects such as unstable control force gain, asymmetrical forward and reverse response, zero-current residual attraction, and operating point drift. To address this technical defect in existing technologies, such as... Figures 1-8As shown in the figure, this embodiment proposes a magnetically isolated axial magnetic levitation bearing structure, which can make the axial control magnetic flux avoid the rotor body with obvious hysteresis effect without reducing the mechanical safety of the rotor, thereby improving the stability and consistency of axial electromagnetic force control. The magnetically shielded axial magnetic levitation bearing structure includes a load-bearing rotor body 1, a magnetically separating rotor assembly 3, and a magnetically separating rotor assembly 2. The load-bearing rotor body 1 is made of high-strength ferromagnetic material and is used to bear high-speed rotation and axial load. An annular groove 301 is provided at its axial end. The magnetically separating rotor assembly 3 is disposed in the annular groove 301 and includes an axial magnetic actuating element 304, a magnetically shielding assembly 303, and a fixing assembly 305. The fixing assembly 305 is a non-magnetic bolt used to fix the axial magnetic actuating element 304 and the magnetically shielding assembly 303 in the annular groove 301 and to transmit the axial electromagnetic attraction force to the load-bearing rotor body 1. The inner sidewall of the annular groove 301 is provided with a mounting boss 302 for providing radial positioning for the magnetically shielding assembly 303 and the axial magnetic actuating element 304. The fixing assembly 305 is disposed on the mounting boss 302 and presses the magnetically shielding assembly 303 and the axial magnetic actuating element 304 axially.

[0022] Specifically, the axial magnetic actuating element 304 is made of a low coercivity soft magnetic material and is used to bear controlled magnetic conduction and generate electromagnetic attraction. The magnetic isolation component 303 is an integrated magnetic isolation sleeve with a U-shaped cross section. Its bottom covers the back of the axial magnetic actuating element 304, and its two sides cover the radial inner and radial outer sides of the axial magnetic actuating element 304, respectively. The axial magnetic actuating element 304 is only exposed to the axial action surface of the magnetic selector component 2. The magnetic isolation component 303 is used to increase the magnetic resistance between the axial magnetic actuating element 304 and the load-bearing rotor body 1, thereby suppressing the control magnetic flux from the non-working surface into the load-bearing rotor body 1.

[0023] The magnetic selector assembly 2 is disposed on the outer side of the load-bearing rotor body 1 along the axial direction, corresponding to the magnetic selector rotor assembly 3. An axial working air gap is formed between the magnetic selector assembly 2 and the axial action surface of the axial magnetic action member 304.

[0024] The magnetic stator assembly 2 includes a soft magnetic stator body 201 and excitation coil one 202 and excitation coil two 203 arranged radially on the soft magnetic stator body 201. Excitation coil one 202 and excitation coil two 203 have the same number of turns, are connected in series in opposite directions, and are driven by the same current source, so that their excitation directions are opposite and their ampere-turn amplitudes are always equal.

[0025] The energizing direction of the two excitation coils is set to form an adjacent first magnetic pole region and a second magnetic pole region on the soft magnetic stator body 201. The magnetic flux path is: first magnetic pole region → axial working air gap → axial magnetic actuating element 304 → axial working air gap → second magnetic pole region → soft magnetic stator body 201 → back to the first magnetic pole region, thereby forming a partially closed control magnetic circuit. This control magnetic circuit mainly passes through the axial magnetic actuating element 304 and does not pass through the load-bearing rotor body 1.

[0026] As can be seen from the above, during operation, the controller will acquire the axial displacement signal of the load-bearing rotor body 1, and generate a current command based on the signal to drive the excitation coil 1 202 and the excitation coil 203, so that the ampere-turn amplitude of the two coils is always equal.

[0027] When it is necessary to adjust the axial support force, the controller will synchronously change the current amplitude of the two coils. At this time, the magnetic flux in the partially closed control magnetic circuit will change accordingly, and the axial attraction of each air gap region will be superimposed in the same direction, thereby realizing the active adjustment of the axial position of the load-bearing rotor body 1.

[0028] Since the magnetic flux in the main control magnetic circuit is carried by the axial magnetic action component 304 with low coercivity and high incremental permeability, the proportion of the load-bearing rotor body 1 participating in the controlled magnetic circuit is greatly reduced, effectively reducing the adverse effects of the material hysteresis and remanence of the load-bearing rotor body 1 on the relationship of axial control force.

[0029] Example 2 In order to further improve the control quality of the axial magnetic levitation bearing structure under zero or low bias conditions and eliminate the influence of long-term unidirectional magnetization accumulation of the axial magnetic actuator 304 on the control accuracy, based on Embodiment 1, this embodiment provides a magnetically isolated axial magnetic levitation bearing structure with a controller and a dual-sided differential structure.

[0030] In this embodiment, annular grooves 301 are provided at both axial ends of the load-bearing rotor body 1. A magnetic separator rotor assembly 3 is provided in each annular groove 301, and magnetic separator assemblies 2 are respectively provided on the two axial outer sides of the load-bearing rotor body 1, forming a double-sided differential axial magnetic levitation support structure. Each magnetic separator assembly 2 includes a soft magnetic stator body 201, an excitation coil 1 202, and an excitation coil 203. The ampere-turns amplitude is equal and the excitation direction is opposite in each coil group.

[0031] The bearing structure also includes a controller, which controls the upper and lower magnetic selector components 2 respectively. The controller combines the static load command q0 with the dynamic control command Δq to obtain the upper scalar excitation command q1=q0+Δq and the lower scalar excitation command q2=q0−Δq. The magnetic selector components 2 on both sides distribute the current according to their respective ampere-turn balance relationship: that is, for each side, the controller generates the current command of the two excitation coils on that side according to a predetermined ratio, so that the ampere-turn amplitude of excitation coil 1 202 and excitation coil 2 203 is kept equal. Thus, when the load-bearing rotor body 1 deviates from the target axial position, the controller will adjust the magnitude and direction of Δq to make the axial electromagnetic attraction force generated on both sides form a force difference, pulling the load-bearing rotor body 1 back to the target position, thereby realizing bidirectional high-precision axial position control.

[0032] In addition, the controller also has demagnetization initialization and global polarity reversal functions. During startup, while maintaining equal ampere-turn amplitudes for each coil, the controller applies alternating positive and negative scalar excitation commands with gradually decreasing amplitudes to demagnetize and initialize the axial magnetic actuator 304, bringing it into a repeatable initial magnetization state. During operation, when the residual magnetic flux detected by the controller exceeds a preset value, the controller simultaneously reverses the excitation direction of all excitation coils while maintaining the ampere-turn ratio between each coil, thus eliminating the long-term unidirectional magnetization accumulation of the axial magnetic actuator 304 and further improving control repeatability.

[0033] Example 3 To meet the application requirements of large-diameter, high-speed flywheel energy storage systems, reduce the processing difficulty of large-size soft magnetic components and eddy current losses during high-speed operation, and simultaneously meet the flexible design requirements of different stator space layouts and temperature rise requirements, this embodiment provides a magnetically isolated axial magnetic levitation bearing structure based on Embodiment 1. Its axial magnetic component 304 adopts a circumferentially segmented structure, and the magnetic stator assembly 2 can adopt an odd-numbered coil configuration or a circumferentially modular stator structure.

[0034] In this embodiment, an annular groove 301 is provided at the axial end of the load-bearing rotor body 1. A magnetic separation rotor assembly 3 is provided in the annular groove 301. The magnetic separation rotor assembly 3 includes an axial magnetic actuating element 304, a magnetic isolation component 303, and a fixing component 305. The magnetic isolation component 303 is an integral magnetic isolation sleeve with a U-shaped cross section, which is provided in the annular groove 301. The axial magnetic actuating element 304 is provided in the receiving space of the magnetic isolation component 303. Its special feature is that the axial magnetic actuating element 304 is not a continuous annular integral part, but is composed of multiple arc-shaped blocks arranged along the circumference. There are non-magnetic intervals between each arc-shaped block. The specific number of arc-shaped blocks can be determined according to the rotor diameter and the operating speed. The axial direction of each arc-shaped block is fixed by the fixing component 305.

[0035] The modular structure reduces circumferential eddy current losses, which helps reduce heat generation during high-speed operation. On the other hand, it releases assembly stress and thermal stress, reducing the processing difficulty and manufacturing cost of large-diameter soft magnetic components.

[0036] The magnetic selector assembly 2 is located axially on the outer side of the load-bearing rotor body 1, corresponding to the magnetic selector rotor assembly 3. In this embodiment, the magnetic selector assembly 2 adopts an odd-numbered configuration of three excitation coils, such as... Figure 9As shown, the soft magnetic stator 201 is arranged radially in sequence with an inner radial excitation coil, a middle excitation coil, and an outer radial excitation coil. The inner and outer radial excitation coils are energized in the same direction, while the middle excitation coil is energized in the opposite direction. The ampere-turns of the middle excitation coil are equal to the sum of the ampere-turns of the inner and outer radial excitation coils. A first partially closed control magnetic circuit is formed between the inner and middle excitation coils, and a second partially closed control magnetic circuit is formed between the middle and outer radial excitation coils. By changing the ampere-turns distribution ratio of the inner and outer radial excitation coils, the magnetic flux density difference caused by the difference in magnetic circuit length and effective area in the inner and outer diameter regions can be flexibly compensated.

[0037] As an alternative, the magnetic selector assembly 2 can also adopt a circumferential modular structure: that is, instead of using a coaxial ring coil, it is divided into multiple sector-shaped modules along the circumference. Each module is equipped with two or three excitation coils with opposite excitation, and each module satisfies the ampere-turn balance inside the module. The axial attraction generated by each module is superimposed in the circumferential direction. The controller can drive each module synchronously, and can also perform group correction control according to the tilt of the load-bearing rotor body 1 or the local air gap error.

[0038] The control method of this invention is automatic control through a controller. The control circuit of the controller can be implemented by simple programming by those skilled in the art. The power supply is also common knowledge in the art. Furthermore, since this invention is mainly used to protect mechanical devices, the control method and circuit connection will not be explained in detail here.

[0039] It should be noted that the terms “comprising,” “including,” or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0040] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A magnetically shielded axial magnetic levitation bearing structure, comprising a load-bearing rotor body (1) for bearing high-speed rotation and axial load, characterized in that: The axial end of the load-bearing rotor body (1) is provided with an annular groove (301), and a magnetic separator rotor assembly (3) is provided in the annular groove (301). A magnetic separator assembly (2) for generating axially controllable electromagnetic attraction is provided on the outer side of the load-bearing rotor body (1) corresponding to the magnetic separator rotor assembly (3). The magnetic separation rotor assembly (3) includes an axial magnetic actuating element (304) made of a low coercivity soft magnetic material and a magnetic isolation assembly (303) disposed between the axial magnetic actuating element (304) and the load-bearing rotor body (1). The magnetic isolation assembly (303) only covers the back side and the two radial sides of the axial magnetic actuating element (304). The magnetic stator assembly (2) includes a soft magnetic stator body (201) and excitation coil one (202) and excitation coil two (203) disposed on the soft magnetic stator body (201). The excitation directions of excitation coil one (202) and excitation coil two (203) are opposite and their ampere-turn amplitudes are equal.

2. The magnetically shielded axial magnetic levitation bearing structure according to claim 1, characterized in that: The magnetic shielding component (303) is an integrated magnetic shielding sleeve with a U-shaped, groove-shaped or cup-shaped cross section. The bottom of the integrated magnetic shielding sleeve covers the back of the axial magnetic action component (304), and the two sides of the integrated magnetic shielding sleeve cover the radial inner side and radial outer side of the axial magnetic action component (304), respectively.

3. The magnetically shielded axial magnetic levitation bearing structure according to claim 1, characterized in that: The inner wall of the annular groove (301) is provided with a mounting boss (302) for mounting the magnetic shielding component (303) and the axial magnetic actuating component (304).

4. The magnetically shielded axial magnetic levitation bearing structure according to claim 3, characterized in that: The mounting boss (302) is provided with a fixing component (305) for axially pressing the magnetic shielding component (303) and the axial magnetic actuating component (304).

5. The magnetically shielded axial magnetic levitation bearing structure according to claim 1, characterized in that: The axial magnetic actuating element (304) is composed of multiple arc-shaped blocks arranged circumferentially, with non-magnetic intervals between each arc-shaped block.

6. The magnetically shielded axial magnetic levitation bearing structure according to claim 1, characterized in that: The excitation coil one (202) and excitation coil two (203) are coaxial ring coils arranged radially on the soft magnetic stator body (201), and the excitation coil one (202) and excitation coil two (203) are connected in series in reverse.

7. The magnetically shielded axial magnetic levitation bearing structure according to claim 1, characterized in that: The load-bearing rotor body (1) has annular grooves (301) at both axial ends, and magnetic separator rotor assemblies (3) are respectively provided in each annular groove (301). Magnetic separator rotor assemblies (2) are respectively provided on the two axial outer sides of the load-bearing rotor body (1).

8. The magnetically shielded axial magnetic levitation bearing structure according to claim 1, characterized in that: It also includes a controller, which is used to acquire the axial displacement signal of the load-bearing rotor body (1) and generate a current command based on the axial displacement signal to keep the ampere-turn amplitude of excitation coil one (202) and excitation coil two (203) equal.

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