Magnetic bearing and compressor

Abstract

The application provides a magnetic suspension bearing and a compressor, and the magnetic suspension bearing comprises a radial stator core and a radial rotor core, the radial stator core is located at the radial outer periphery of the radial rotor core along the radial direction of the magnetic suspension bearing, and a radial air gap is formed between the radial stator core and the radial rotor core, the radial stator core has a first end face facing the radial rotor core, the first end face is provided with a first Halbach array permanent magnet, the radial rotor core has a second end face facing the radial stator core, the second end face is provided with a second Halbach array permanent magnet, and the first Halbach array permanent magnet and the second Halbach array permanent magnet are arranged in at least partial structural opposition. According to the application, the air gap magnetic field strength can be effectively increased, and the utilization rate of the permanent magnet is improved; and the technical problem of low air gap magnetic field strength of the magnetic suspension bearing in the prior art is effectively solved.

Description

Technical Field

[0001] This invention relates to the field of magnetic levitation bearing technology, specifically to a magnetic levitation bearing and compressor, belonging to the category of energy-saving pumps and energy-saving gas compressors. Background Technology

[0002] Magnetic levitation bearings are a new type of high-performance bearing that uses magnetic force to suspend and support the rotor without mechanical contact. They have advantages such as no friction and mechanical wear, no lubrication or sealing, high speed and long service life, and are widely used in aerospace, medical equipment, rail transportation, flywheel energy storage and other industrial fields.

[0003] Halbach array is a novel type of permanent magnet array. Existing technologies use a Halbach-based axial passive magnetic bearing and a three-degree-of-freedom radial hybrid magnetic bearing, which have low air gap magnetic field strength, resulting in low utilization of permanent magnets.

[0004] Because existing magnetic levitation bearings suffer from technical problems such as low air gap magnetic field strength, this invention researches and designs a magnetic levitation bearing and compressor, which belong to the category of energy-saving pumps and energy-saving gas compressors. Summary of the Invention

[0005] Therefore, the technical problem to be solved by the present invention is to overcome the defect of low air gap magnetic field strength in the existing magnetic levitation bearing, thereby providing a magnetic levitation bearing and compressor, which belong to the category of energy-saving pumps and energy-saving gas compressors.

[0006] To address the above problems, the present invention provides a magnetic levitation bearing, comprising: The radial stator core and the radial rotor core are arranged along the radial direction of the magnetic levitation bearing. The radial stator core is located on the radial outer periphery of the radial rotor core, and there is a radial air gap between the radial stator core and the radial rotor core. The radial stator core has a first end face facing the radial rotor core, and a first Halbach array permanent magnet is disposed on the first end face. The radial rotor core has a second end face facing the radial stator core, and a second Halbach array permanent magnet is disposed on the second end face. The first Halbach array permanent magnet and the second Halbach array permanent magnet are arranged with at least partial structural opposition.

[0007] In some implementations... A first groove is formed on the first end face in a direction away from the radial rotor core, and at least a portion of the structure of the first Halbach array permanent magnet is disposed in the first groove. A second groove is formed on the second end face in a direction away from the radial stator core, and at least a portion of the structure of the second Halbach array permanent magnet is disposed in the second groove.

[0008] In some implementations... The entire structure of the first Halbach array permanent magnet is disposed in the first groove, and the end face of the first Halbach array permanent magnet facing the radial rotor core is flush with the first end face. The entire structure of the second Halbach array permanent magnet is disposed in the second groove, and the end face of the second Halbach array permanent magnet facing the radial stator core is flush with the second end face.

[0009] In some implementations... Along the axial direction of the magnetic levitation bearing, the first Halbach array permanent magnet and the second Halbach array permanent magnet are offset in the axial direction, that is, there is a partial structural misalignment between the first Halbach array permanent magnet and the second Halbach array permanent magnet along the axial direction.

[0010] In some implementations... Along the radial direction of the magnetic levitation bearing, a portion of the structure of the first Halbach array permanent magnet and a portion of the structure of the second Halbach array permanent magnet are arranged opposite each other along the radial direction. A portion of the structure of the first Halbach array permanent magnet is not opposite to the second Halbach array permanent magnet along the radial direction, and a portion of the structure of the second Halbach array permanent magnet is not opposite to the first Halbach array permanent magnet along the radial direction.

[0011] In some implementations... It also includes a rotor, which is located on the radial inner circumference of the radial rotor core along the radial direction of the magnetic levitation bearing, and a magnetic shielding structure is provided between the radial rotor core and the rotor.

[0012] In some implementations... It also includes a first axial stator core, which includes a first shaft segment along the axial direction of the magnetic levitation bearing. The first shaft segment is located on one side of the rotor's axial direction, and a first axial air gap is formed between the first shaft segment and the rotor. A first axial winding is provided on the first shaft segment to form a first axial control magnetic circuit on the first shaft segment, the first axial air gap, and the rotor.

[0013] In some implementations... It also includes a second axial stator core, which includes a second shaft segment along the axial direction of the magnetic levitation bearing. The second shaft segment is located on the other side of the rotor's axial direction, and a second axial air gap is formed between the second shaft segment and the rotor. A second axial winding is provided on the second shaft segment to form a second axial control magnetic circuit on the second shaft segment, the second axial air gap, and the rotor.

[0014] In some implementations... The first axial stator core includes a third shaft segment and a fourth shaft segment. Along the radial direction of the magnetic levitation bearing, one end of the third shaft segment is connected to the radially outer end of the first shaft segment and extends in a radially outward direction. Along the axial direction of the magnetic levitation bearing, the fourth shaft segment extends along the axial direction, with one axial end of the fourth shaft segment extending to connect with the third shaft segment. A portion of the structure of the fourth shaft segment extends to the outer periphery of the radial stator core and connects with the radial stator core. The second axial stator core includes a fifth shaft segment and a sixth shaft segment. Along the radial direction of the magnetic levitation bearing, one end of the fifth shaft segment is connected to the radial outer end of the second shaft segment and extends in a radially outward direction. Along the axial direction of the magnetic levitation bearing, the sixth shaft segment extends along the axial direction, with one axial end of the sixth shaft segment extending to connect with the fifth shaft segment. A portion of the structure of the sixth shaft segment extends to the outer periphery of the radial stator core and connects with the radial stator core. The other axial end of the fourth shaft segment is connected to the other axial end of the sixth shaft segment along the axial direction.

[0015] In some implementations... The first shaft segment extends along the axial direction of the magnetic levitation bearing and along the radial direction of the magnetic levitation bearing. The first shaft segment has two segments spaced apart, and a first space is formed between the two segments to accommodate the first axial winding. The first axial winding is located in the first space and is wound around the first shaft segment on the radial inner circumference. Two segments of the first axial air gap are formed between the two segments of the first shaft segment and the rotor. The second shaft segment extends along the axial direction of the magnetic levitation bearing and along the radial direction of the magnetic levitation bearing. The second shaft segment has two spaced-apart sections, and a second space is formed between the two sections to accommodate the second axial winding. The second axial winding is located in the second space and is wound on the second shaft segment on the radial inner circumference. Two second axial air gaps are formed between the two sections of the second shaft segment and the rotor.

[0016] The present invention also provides a compressor comprising the aforementioned magnetic levitation bearing.

[0017] The magnetic levitation bearing and compressor provided by this invention have the following beneficial effects: 1. This invention provides a magnetic levitation bearing, belonging to the category of energy-saving pumps and energy-saving gas compressors. The radial stator core has a first end face facing the radial rotor core, on which a first Halbach array permanent magnet is disposed. The radial rotor core has a second end face facing the radial stator core, on which a second Halbach array permanent magnet is disposed. The first and second Halbach array permanent magnets are at least partially structurally opposed, enabling the radial magnetic bearing to employ Halbach array permanent magnets. This provides unilateral magnetic shielding capability, effectively increasing the air gap magnetic field strength, improving permanent magnet utilization, enhancing radial stiffness, and simplifying control. This effectively solves the technical problem of low air gap magnetic field strength in existing magnetic levitation bearing systems.

[0018] 2. Furthermore, the present invention further utilizes a first axial stator core and a second axial stator core in the axial direction, respectively, to set a first axial winding and a second axial winding, thereby forming an axially active control + radially passive magnetic levitation bearing, forming a three-degree-of-freedom hybrid magnetic levitation bearing + a structure using Halbach array permanent magnets in the radial direction. This provides more constraints for the hybrid magnetic levitation bearing of the present invention, improves the overall stiffness of the system, increases the axial anti-interference capability of the bearing, and makes the magnetic bearing structure more compact and lower in cost.

[0019] 3. The present invention, by using two first shaft segments arranged radially at one end of the rotor axis and two second shaft segments arranged radially at the other end of the rotor axis, can form two first axial air gaps and two second axial air gaps in the axial direction, forming a total of four axial air gaps. Compared with the existing two air gaps, this can reduce magnetic leakage and magnetic loss. Attached Figure Description

[0020] Figure 1 This is a longitudinal sectional view of the internal structure and magnetic circuit diagram of the Halbach-based hybrid magnetic bearing of the present invention.

[0021] The reference numerals in the attached figures are as follows: 1. Front axial stator core; 13. First shaft segment; 14. Third shaft segment; 15. Fourth shaft segment; 2. First axial winding; 3. Second Halbach array permanent magnet; 4. Radial stator core; 41. First end face; 5. First Halbach array permanent magnet; 6. Second axial stator core; 61. Second shaft segment; 62. Fifth shaft segment; 63. Sixth shaft segment; 7. Magnetic isolation structure; 8. Second axial winding; 9. First axial control magnetic circuit; 10. Second axial control magnetic circuit; 11. Rotor; 12. Radial rotor core; 121. Second end face; g3. Radial air gap; g1. First axial air gap; g2. Second axial air gap. Detailed Implementation

[0022] 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. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. 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.

[0023] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0024] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the invention. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following figures denote similar items; therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0025] In the description of this invention, it should be understood that the orientation or positional relationship indicated by directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" is generally based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing this invention and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the scope of protection of this invention; the directional terms "inner" and "outer" refer to the inner and outer contours relative to the outline of each component itself.

[0026] For ease of description, spatial relative terms such as "above," "on top of," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation beyond the orientation of the device as described in the figures. For example, if the device in the figures were inverted, a device described as "above" or "on top of" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0027] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore should not be construed as limiting the scope of protection of this invention.

[0028] like Figure 1 As shown, the present invention provides a magnetic levitation bearing, which includes: Radial stator core 4 and radial rotor core 12 are located along the radial direction of the magnetic levitation bearing. The radial stator core 4 is located on the radial outer periphery of the radial rotor core 12, and there is a radial air gap g3 between the radial stator core 4 and the radial rotor core 12. The radial stator core 4 has a first end face 41 facing the radial rotor core 12, and a first Halbach array permanent magnet 5 is disposed on the first end face 41. The radial rotor core 12 has a second end face 121 facing the radial stator core 4, and a second Halbach array permanent magnet 3 is disposed on the second end face 121. The first Halbach array permanent magnet 5 and the second Halbach array permanent magnet 3 are at least partially structurally opposed.

[0029] The Halbach array is a special permanent magnet arrangement structure. Through a specific arrangement of magnets, the magnetic field is significantly enhanced on one side while canceling each other out on the other side, thus achieving the strongest unilateral magnetic field effect with the least amount of magnetic material. Halbach array permanent magnets are mainly divided into two forms: cylindrical and linear.

[0030] This invention provides a magnetic levitation bearing as described above, belonging to the category of energy-saving pumps and energy-saving gas compressors. The radial stator core has a first end face facing the radial rotor core, on which a first Halbach array permanent magnet is disposed. The radial rotor core has a second end face facing the radial stator core, on which a second Halbach array permanent magnet is disposed. The first and second Halbach array permanent magnets are arranged with at least partial structural opposition, enabling the radial magnetic bearing to employ Halbach array permanent magnets. This provides unilateral magnetic shielding capability, effectively increasing the air gap magnetic field strength, improving permanent magnet utilization, enhancing radial stiffness, and simplifying control. This effectively solves the technical problem of low air gap magnetic field strength in existing magnetic levitation bearing systems.

[0031] In some implementations... A first groove is formed on the first end face 41 in a direction away from the radial rotor core 12, and at least a portion of the structure of the first Halbach array permanent magnet 5 is disposed in the first groove. A second groove is formed on the second end face 121 in a direction away from the radial stator core 4, and at least a portion of the structure of the second Halbach array permanent magnet 3 is disposed in the second groove.

[0032] This is a preferred structural form of the magnetic levitation bearing of the present invention. A first groove formed by recessing on the first end face can accommodate a first Halbach array permanent magnet for fixing and magnetic conduction. A second groove formed by recessing on the second end face can accommodate a second Halbach array permanent magnet for fixing and magnetic conduction. The first and second Halbach array permanent magnets are structurally opposite each other, which can play a role in magnetic conduction, effectively increasing the air gap magnetic field strength, improving the utilization rate of permanent magnets, and enhancing radial stiffness.

[0033] In some implementations... The entire structure of the first Halbach array permanent magnet 5 is disposed in the first groove, and the end face of the first Halbach array permanent magnet 5 facing the radial rotor core 12 is flush with the first end face 41. The entire structure of the second Halbach array permanent magnet 3 is disposed in the second groove, and the end face of the second Halbach array permanent magnet 3 facing the radial stator core 4 is flush with the second end face 121.

[0034] This is a further preferred configuration of the Halbach array permanent magnet and the groove in this invention. The first Halbach array permanent magnet is completely placed in the first groove, with its surface flush with the first end face. This ensures the integrity and uniformity of the magnetic circuit and achieves the strongest unilateral magnetic field effect. The second Halbach array permanent magnet is completely placed in the second groove, with its surface flush with the second end face. This ensures the integrity and uniformity of the magnetic circuit and achieves the strongest unilateral magnetic field effect. The relative structures of the first and second Halbach array permanent magnets enable magnetic conduction, effectively increasing the air gap magnetic field strength, improving the utilization rate of the permanent magnet, and enhancing radial stiffness.

[0035] In some implementations... Along the axial direction of the magnetic levitation bearing, the first Halbach array permanent magnet 5 and the second Halbach array permanent magnet 3 are offset in the axial direction, that is, there is a partial structural misalignment between the first Halbach array permanent magnet 5 and the second Halbach array permanent magnet 3 along the axial direction.

[0036] This is a further preferred configuration of the first and second Halbach array permanent magnets of the present invention. By arranging the first and second Halbach array permanent magnets with a certain axial offset, the radial load-bearing capacity can be further increased while also improving the radial stiffness.

[0037] In some implementations... Along the radial direction of the magnetic levitation bearing, a portion of the structure of the first Halbach array permanent magnet 5 and a portion of the structure of the second Halbach array permanent magnet 3 are arranged opposite each other along the radial direction. A portion of the structure of the first Halbach array permanent magnet 5 is not opposite to the second Halbach array permanent magnet 3 along the radial direction, and a portion of the structure of the second Halbach array permanent magnet 3 is not opposite to the first Halbach array permanent magnet 5 along the radial direction.

[0038] This is a further preferred structural form of the first and second Halbach array permanent magnets of the present invention, wherein a portion of their structures are opposite each other in the radial direction, a portion of the structure of the first Halbach array permanent magnet extends radially beyond the second Halbach array permanent magnet, i.e., it is not opposite to the second Halbach array permanent magnet, and a portion of the structure of the second Halbach array permanent magnet extends radially beyond the first Halbach array permanent magnet, i.e., it is not opposite to the first Halbach array permanent magnet. This can create an axial offset between the first and second Halbach array permanent magnets. The first Halbach array permanent magnet and the second Halbach permanent magnet have a certain axial offset, which can further improve the radial bearing capacity and further increase the radial stiffness.

[0039] In some implementations... It also includes a rotor 11, which is located on the radial inner circumference of the radial rotor core 12 along the radial direction of the magnetic levitation bearing, and a magnetic shielding structure 7 is provided between the radial rotor core 12 and the rotor 11. The rotor 11 and the radial rotor core are preferably integrally formed.

[0040] The present invention preferably uses a rotor that can withstand the magnetic force of the radial stator core. The radial magnetic levitation force is first applied to the radial rotor core and then transmitted to the rotor through the connection between the rotor and the radial rotor core, thereby achieving radial magnetic levitation of the shaft. The present invention provides a magnetic shielding structure (preferably a magnetic shielding ring) between the radial rotor core and the rotor, which can effectively shield the magnetic field between the radial rotor core and the rotor, prevent magnetic leakage, and provide radial magnetic levitation force. The rotor and radial stator core are integrally formed. More preferably, the rotor, radial rotor core and magnetic shielding ring are integrally formed, which can improve processing efficiency, ensure effective connection between the rotor and the radial rotor core, and achieve magnetic shielding function through the magnetic shielding ring.

[0041] In some implementations... It also includes a first axial stator core 1, which includes a first shaft segment 13 along the axial direction of the magnetic levitation bearing. The first shaft segment 13 is located on one side of the axial direction of the rotor 11, and a first axial air gap g1 is formed between the first shaft segment 13 and the rotor 11. A first axial winding 2 is provided on the first shaft segment 13 to form a first axial control magnetic circuit 9 on the first shaft segment 13, the first axial air gap g1 and the rotor 11. It also includes a second axial stator core 6, which includes a second shaft segment 61 along the axial direction of the magnetic levitation bearing. The second shaft segment 61 is located on the other side of the axial direction of the rotor 11, and a second axial air gap g2 is formed between the second shaft segment 61 and the rotor 11. A second axial winding 8 is provided on the second shaft segment 61 to form a second axial control magnetic circuit 10 on the second shaft segment 61, the second axial air gap g2 and the rotor 11.

[0042] The present invention further utilizes a first axial stator core and a second axial stator core, respectively, to set a first axial winding and a second axial winding, thereby forming an axially active control + radially passive magnetic levitation bearing. This results in a three-degree-of-freedom hybrid magnetic levitation bearing with a structure using Halbach array permanent magnets in the radial direction. This provides more constraints for the hybrid magnetic levitation bearing of the present invention, improves the overall stiffness of the system, increases the axial anti-interference capability of the bearing, and makes the magnetic bearing structure more compact and lower in cost.

[0043] In some implementations... The first axial stator core 1 includes a third shaft segment 14 and a fourth shaft segment 15. Along the radial direction of the magnetic levitation bearing, one end of the third shaft segment 14 is connected to the radial outer end of the first shaft segment 13 and extends in a radially outward direction. Along the axial direction of the magnetic levitation bearing, the fourth shaft segment 15 extends along the axial direction. One axial end of the fourth shaft segment 15 extends to connect with the third shaft segment 14. A portion of the structure of the fourth shaft segment 15 extends to the outer periphery of the radial stator core 4 and connects with the radial stator core 4. The second axial stator core 6 includes a fifth shaft segment 62 and a sixth shaft segment 63. Along the radial direction of the magnetic levitation bearing, one end of the fifth shaft segment 62 is connected to the radial outer end of the second shaft segment 61 and extends in a radially outward direction. Along the axial direction of the magnetic levitation bearing, the sixth shaft segment 63 extends along the axial direction. One axial end of the sixth shaft segment 63 extends to connect with the fifth shaft segment 62. A portion of the structure of the sixth shaft segment 63 extends to the outer periphery of the radial stator core 4 and connects with the radial stator core 4. The other axial end of the fourth shaft segment 15 is connected to the other axial end of the sixth shaft segment 63 along the axial direction.

[0044] This is a further preferred structural form of the magnetic levitation bearing of the present invention. The present invention can form two first axial air gaps and two second axial air gaps in the axial direction by means of two first shaft segments arranged in the radial direction at one end of the rotor axial direction and two second shaft segments arranged in the radial direction at the other end of the rotor axial direction, forming a total of four axial air gaps. Compared with the existing two air gaps, it can reduce magnetic leakage and reduce magnetic loss.

[0045] The hybrid magnetic levitation bearing of the present invention, such as Figure 1 As shown, the magnetic isolation structure 7 is embedded between the rotor 11 and the radial rotor core 12. The second Halbach array permanent magnet 3 is placed on the radial rotor core 12, and the first Halbach array permanent magnet 5 is placed on the radial stator core 4. The first Halbach array permanent magnet 5 and the second Halbach array permanent magnet 3 have a certain axial offset. The first axial winding 2 (front axial control winding) is wound around the first axial stator core 1 (front axial stator core), and the second axial winding 8 (rear axial control winding) is wound around the second axial stator core 6. The first axial air gap g1 is between the first axial stator core 1 and the rotor 11. The first axial winding 2 generates the first axial control magnetic circuit 9 when energized. The second axial air gap g2 is between the second axial stator core 6 and the rotor 11. The second axial control winding 8 generates the second axial control magnetic circuit 10 when energized. The radial air gap g3 is between the first Halbach array permanent magnet 5 and the second Halbach array permanent magnet 3.

[0046] Axial bearing control logic: Axial control magnetic circuit as follows Figure 1 As shown, when the first axial air gap g1 is larger than the second axial air gap g2, the current in the first axial winding 2 increases, the magnetic flux density in the first axial air gap g1 increases, and the magnetic pole attraction at that point is greater than on the opposite side. The rotor then shifts towards that magnetic pole side (moves to the left), and the axial air gap rebalances. Conversely, when the second axial air gap g2 is smaller than the first axial air gap g1, the current in the second axial winding 8 increases, the magnetic flux density in the second axial air gap g2 increases, and the magnetic pole attraction at that point is greater than on the opposite side. The rotor then shifts towards that magnetic pole side, and the radial air gap rebalances. A differential control method is used in the axial direction. When the axial current on one side increases, the axial current on the symmetrical side decreases accordingly, allowing for air gap balance through smaller current changes.

[0047] The radial bearing magnetic levitation force of the present invention is passively controlled, and the radial air gap g3 is provided with levitation force by the first Halbach array permanent magnet 5 and the second Halbach array permanent magnet 3.

[0048] The present invention also provides a compressor comprising the aforementioned magnetic levitation bearing.

[0049] The existing technical solution uses a Halbach-based axial passive magnetic bearing and a three-degree-of-freedom radial hybrid magnetic bearing. Its air gap magnetic field strength is low, resulting in low utilization of permanent magnets. In addition, it has many control parameters, complex structure, long axial dimension, and low critical speed.

[0050] This invention proposes a novel hybrid magnetic levitation bearing that combines radial and axial magnetic levitation bearings. The radial magnetic bearing employs a Halbach-based passive structure, resulting in a more compact bearing structure and simpler control. The use of a Halbach-based passive magnetic bearing in the radial configuration effectively increases the air gap magnetic field strength and enhances radial stiffness.

[0051] The beneficial effects of the hybrid magnetic levitation bearing of the present invention: 1. The hybrid magnetic levitation bearing of the present invention uses a Halbach permanent magnet array in the radial direction, which has a single-sided magnetic shielding capability, effectively increasing the air gap magnetic field strength, improving the utilization rate of permanent magnets, enhancing radial stiffness, and making control simpler; it provides more constraints, improves the overall stiffness of the system, increases the axial anti-interference capability of the bearing, and makes the magnetic bearing structure more compact and lower in cost.

[0052] 2. By employing a Halbach permanent magnet array, this invention avoids the use of conventional permanent magnets or conventional coil structures, thereby significantly shortening the axial length of the magnetic bearing. This overcomes the limitations of high power and ultra-high speed and enables miniaturization. This invention only requires changing the magnitude and direction of the current in the first axial winding 2 and the second axial winding 8 to achieve axial control. Radial control is not required, and the radial bearing structure is simple, resulting in a smaller structural size (especially the axial length) and simpler control logic.

[0053] 4. The upper Halbach array permanent magnet (first Halbach array permanent magnet) and the lower Halbach array permanent magnet (second Halbach array permanent magnet) of the present invention have a certain axial offset, which can improve the radial bearing capacity and increase the radial stiffness.

[0054] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention. The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the protection scope of the present invention.

Claims

1. A magnetic levitation bearing, characterized in that: include: Radial stator core (4) and radial rotor core (12) are located on the radial outer periphery of the radial rotor core (12) along the radial direction of the magnetic levitation bearing. A radial air gap (g3) exists between the radial stator core (4) and the radial rotor core (12). The radial stator core (4) has a first end face (41) facing the radial rotor core (12). A first Halbach array permanent magnet (5) is provided on the first end face (41). The radial rotor core (12) has a second end face (121) facing the radial stator core (4). A second Halbach array permanent magnet (3) is provided on the second end face (121). The first Halbach array permanent magnet (5) and the second Halbach array permanent magnet (3) are arranged with at least partial structural opposition.

2. The magnetic levitation bearing according to claim 1, characterized in that: A first groove is formed on the first end face (41) in a direction away from the radial rotor core (12), and at least a portion of the structure of the first Halbach array permanent magnet (5) is disposed in the first groove. A second groove is formed on the second end face (121) in a direction away from the radial stator core (4), and at least a portion of the structure of the second Halbach array permanent magnet (3) is disposed in the second groove.

3. The magnetic levitation bearing according to claim 2, characterized in that: The entire structure of the first Halbach array permanent magnet (5) is disposed in the first groove. The end face of the first Halbach array permanent magnet (5) facing the radial rotor core (12) is flush with the first end face (41). The entire structure of the second Halbach array permanent magnet (3) is disposed in the second groove. The end face of the second Halbach array permanent magnet (3) facing the radial stator core (4) is flush with the second end face (121).

4. The magnetic levitation bearing according to claim 1, characterized in that: Along the axial direction of the magnetic levitation bearing, the first Halbach array permanent magnet (5) and the second Halbach array permanent magnet (3) are offset in the axial direction, that is, the first Halbach array permanent magnet (5) and the second Halbach array permanent magnet (3) have partial structural misalignment along the axial direction.

5. The magnetic levitation bearing according to claim 4, characterized in that: Along the radial direction of the magnetic levitation bearing, a portion of the structure of the first Halbach array permanent magnet (5) and a portion of the structure of the second Halbach array permanent magnet (3) are arranged opposite each other along the radial direction. A portion of the structure of the first Halbach array permanent magnet (5) is not opposite to the second Halbach array permanent magnet (3) along the radial direction, and a portion of the structure of the second Halbach array permanent magnet (3) is not opposite to the first Halbach array permanent magnet (5) along the radial direction.

6. The magnetic levitation bearing according to claim 1, characterized in that: It also includes a rotor (11) along the radial direction of the magnetic levitation bearing, the rotor (11) being located on the radial inner circumference of the radial rotor core (12), and a magnetic shielding structure (7) being provided between the radial rotor core (12) and the rotor (11).

7. The magnetic levitation bearing according to claim 6, characterized in that: It also includes a first axial stator core (1), which includes a first shaft segment (13) along the axial direction of the magnetic levitation bearing. The first shaft segment (13) is located on one side of the axial direction of the rotor (11). A first axial air gap (g1) is formed between the first shaft segment (13) and the rotor (11). A first axial winding (2) is provided on the first shaft segment (13) to form a first axial control magnetic circuit (9) on the first shaft segment (13), the first axial air gap (g1) and the rotor (11). It also includes a second axial stator core (6), which includes a second shaft segment (61) along the axial direction of the magnetic levitation bearing. The second shaft segment (61) is located on the other side of the rotor (11) in the axial direction. A second axial air gap (g2) is formed between the second shaft segment (61) and the rotor (11). A second axial winding (8) is provided on the second shaft segment (61) to form a second axial control magnetic circuit (10) on the second shaft segment (61), the second axial air gap (g2) and the rotor (11).

8. The magnetic levitation bearing according to claim 7, characterized in that: The first axial stator core (1) includes a third shaft segment (14) and a fourth shaft segment (15). Along the radial direction of the magnetic levitation bearing, one end of the third shaft segment (14) is connected to the radial outer end of the first shaft segment (13) and extends in a radially outward direction. Along the axial direction of the magnetic levitation bearing, the fourth shaft segment (15) extends along the axial direction. One axial end of the fourth shaft segment (15) extends to connect with the third shaft segment (14). A portion of the structure of the fourth shaft segment (15) extends to the outer periphery of the radial stator core (4) and connects with the radial stator core (4). The second axial stator core (6) includes a fifth shaft segment (62) and a sixth shaft segment (63). Along the radial direction of the magnetic levitation bearing, one end of the fifth shaft segment (62) is connected to the radial outer end of the second shaft segment (61) and extends in a radially outward direction. Along the axial direction of the magnetic levitation bearing, the sixth shaft segment (63) extends along the axial direction. One axial end of the sixth shaft segment (63) extends to connect with the fifth shaft segment (62). A portion of the structure of the sixth shaft segment (63) extends to the outer periphery of the radial stator core (4) and connects with the radial stator core (4). The other axial end of the fourth shaft segment (15) is connected to the other axial end of the sixth shaft segment (63) along the axial direction.

9. The magnetic levitation bearing according to claim 7, characterized in that: The first shaft segment (13) extends along the axial direction of the magnetic levitation bearing and along the radial direction of the magnetic levitation bearing. The first shaft segment (13) has two segments spaced apart, and a first space is formed between the two segments of the first shaft segment (13) to accommodate the first axial winding (2). The first axial winding (2) is located in the first space and is wound on the first shaft segment (13) on the radial inner circumference. Two segments of the first axial air gap (g1) are formed between the two segments of the first shaft segment (13) and the rotor (11). The second shaft segment (61) extends along the axial direction of the magnetic levitation bearing and along the radial direction of the magnetic levitation bearing. The second shaft segment (61) has two segments spaced apart, and a second space is formed between the two segments of the second shaft segment (61) to accommodate the second axial winding (8). The second axial winding (8) is located in the second space and is wound on the second shaft segment (61) on the radial inner circumference. Two second axial air gaps (g2) are formed between the two segments of the second shaft segment (61) and the rotor (11).

10. A compressor, characterized in that: The magnetic levitation bearing includes any one of claims 1-9.

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