CN113586609A

CN113586609A - Magnetic suspension bearing, motor, compressor and air conditioner

Info

Publication number: CN113586609A
Application number: CN202111002094.2A
Authority: CN
Inventors: 胡余生; 郭伟林; 龚高; 张芳; 张超; 吴瑞
Original assignee: Gree Electric Appliances Inc of Zhuhai
Current assignee: Gree Electric Appliances Inc of Zhuhai
Priority date: 2021-08-30
Filing date: 2021-08-30
Publication date: 2021-11-02
Also published as: WO2023029538A1

Abstract

The application provides a magnetic suspension bearing, a motor, a compressor and an air conditioner. This magnetic suspension bearing includes axial magnetic field control portion, radial magnetic field control portion and rotor subassembly, the rotor subassembly includes rotor core, axial magnetic field control portion includes the axial control end that sets up relatively with rotor core's terminal surface, the axial control end is provided with the axial control winding, radial magnetic field control portion includes the radial control end that sets up relatively with rotor core's outer peripheral face, the radial control end is provided with the radial control winding, be provided with the permanent magnet between the axial magnetic field control portion at both ends and the radial magnetic field control portion respectively, the axial magnetic field control portion that the permanent magnet held for this permanent magnet provides bias magnetic field, the permanent magnet at both ends provides bias magnetic field for radial magnetic field control portion jointly. According to the magnetic suspension bearing, the front axial control magnetic field and the rear axial control magnetic field are independent and do not interfere with each other, the front axial control system and the rear axial control system are independent, the control logic is simplified, and the system stability is improved.

Description

Magnetic suspension bearing, motor, compressor and air conditioner

Technical Field

The application relates to the technical field of magnetic suspension, in particular to a magnetic suspension bearing, a motor, a compressor and an air conditioner.

Background

The magnetic suspension bearing has a series of excellent qualities of no contact, no abrasion, high rotating speed, high precision, no need of lubrication and sealing and the like, and is a high and new technical product integrating electromagnetism, electronic technology, control engineering, signal processing and mechanics.

The magnetic suspension bearing is divided into three types of active type, passive type and hybrid type, the active type magnetic suspension bearing has high rigidity and can be precisely controlled, but the volume and the power consumption required for generating unit bearing capacity are large; the passive magnetic suspension bearing realizes the suspension of the rotor by utilizing the attraction force or the repulsion force between magnetic materials, and has lower rigidity and damping; the hybrid magnetic suspension bearing uses a permanent magnet to provide a bias magnetic field to replace a static bias magnetic field generated by an electromagnet in an active magnetic bearing, reduces the ampere-turns of a control winding, reduces the volume of the bearing, improves the bearing capacity of the bearing and the like; the hybrid magnetic suspension bearing has irreplaceable advantages in the field with strict requirements on volume and power consumption, and the magnetic suspension bearing is mainly applied to high-speed and ultra-high-speed occasions. Therefore, the integration and miniaturization of the magnetic levitation system and the improvement of the stability and reliability of the control system will be the key research directions.

Referring to fig. 5, in the hybrid three-degree-of-freedom magnetic suspension bearing structure in the related art, a permanent magnet 6 'generates a bias magnetic field, an axial-radial bias magnetic field 3' is formed by the radial bearing 7 ', the rotating shaft 1', the left and right axial iron cores 2 ', an axial control magnetic circuit 4' is formed by the axial control winding 5 'generating a control magnetic field, and the axial control magnetic circuit 4' regulates and controls the bias magnetic flux of the bias magnetic field in the axial gap between the rotating shaft and the axial iron core, so as to realize axial suspension control. In the same way, the radial control winding 9 'generates a radial control magnetic circuit 8' to regulate and control the radial gap bias magnetic flux of the radial bearing and the rotating shaft, so that the radial suspension of the rotating shaft is realized.

The front and back axial control magnetic fields of the magnetic suspension system structure are coupled to control axial suspension, axial and radial control magnetic circuits are mutually interfered, the control logic is complex, and the system stability is low.

Disclosure of Invention

Therefore, the technical problem to be solved by the application is to provide a magnetic suspension bearing, a motor, a compressor and an air conditioner, which can enable front and rear axial control magnetic fields to be mutually independent and not to interfere with each other, realize the independence of a front and rear axial control system, simplify control logic and improve system stability.

In order to solve the above problem, the application provides a magnetic suspension bearing, including axial magnetic field control portion, radial magnetic field control portion and rotor subassembly, the both ends of radial magnetic field control portion are provided with axial magnetic field control portion respectively, the rotor subassembly includes rotor core, axial magnetic field control portion includes the axial control end that sets up relatively with rotor core's terminal surface, the axial control end is provided with the axial control winding, radial magnetic field control portion includes the radial control end that sets up relatively with rotor core's outer peripheral face, the radial control end is provided with the radial control winding, be provided with the permanent magnet between the axial magnetic field control portion at both ends and the radial magnetic field control portion respectively, the permanent magnet provides bias magnetic field for the axial magnetic field control portion of this permanent magnet place end, the permanent magnet at both ends provides bias magnetic field for radial magnetic field control portion jointly.

Preferably, the permanent magnet is disposed on an outer peripheral side of the axial magnetic field control portion, and the radial magnetic field control portion is disposed on an outer peripheral side of the permanent magnet.

Preferably, the axial magnetic field control portion further includes an axial iron core, the axial iron core is disposed opposite to the end face of the rotor iron core, and the axial control winding is disposed at one end of the axial iron core facing the rotor iron core.

Preferably, the axial iron core includes a magnetic conductive plate, the magnetic conductive plate is provided with an annular protrusion protruding toward the rotor iron core, the annular protrusion is provided with an annular slot, the axial control winding is arranged in the annular slot, and the permanent magnet is arranged on the outer peripheral side of the magnetic conductive plate.

Preferably, the annular protrusion is formed with a first axial control magnetic pole and a second axial control magnetic pole, and the control magnetic field generated by the axial magnetic field control part forms an axial control magnetic field through the first axial control magnetic pole, the rotor core, and the second axial control magnetic pole.

Preferably, in the axial direction, the radius of the first axial control pole is smaller than the radius of the second axial control pole, the air gap distance between the first axial control pole and the rotor core is L1, the air gap distance between the second axial control pole and the rotor core is L2, and L1 is greater than L2.

Preferably, the radius of the second axial control pole is smaller than the radius of the rotor core.

Preferably, the radial magnetic field control portion includes a radial iron core and magnetic rings located at two axial ends of the radial iron core, the magnetic rings are disposed on the outer peripheral side of the permanent magnet, the radial iron core is sleeved outside the rotor iron core, the radial iron core includes radial teeth, and the radial control winding is wound on the radial teeth.

Preferably, the radial iron core is divided into a plurality of iron core segments along the circumferential direction, and the plurality of iron core segments are magnetically isolated through a magnetic isolation structure.

Preferably, the magnetism isolating structure comprises magnetism isolating plates, and the magnetism isolating plates are arranged between two adjacent iron core sections at intervals.

Preferably, the magnetism isolating structure further comprises a magnetism isolating ring, the magnetism isolating ring is arranged between the magnetic conducting ring and the radial iron core at intervals, the magnetism isolating plate is arranged on the magnetism isolating ring, an avoiding groove is formed in the magnetism isolating ring, a magnetic conducting bulge is arranged on the magnetic conducting ring, the magnetic conducting bulge is arranged in the avoiding groove, and a magnetic conducting channel is formed between the magnetic conducting ring and the radial iron core through the magnetic conducting bulge.

Preferably, the magnetism isolating plates are uniformly distributed at intervals along the circumferential direction of the magnetism isolating ring, the avoiding grooves are uniformly distributed at intervals along the circumferential direction of the magnetism isolating ring, and the magnetism isolating plates and the avoiding grooves are alternately distributed along the circumferential direction of the magnetism isolating ring.

Preferably, the magnetism isolating plate and the magnetism isolating ring are integrally formed.

Preferably, the avoiding groove is located at the middle position of two adjacent magnetism isolating plates along the circumferential direction.

Preferably, the radial iron core is circumferentially divided into four iron core sections, the four iron core sections are divided into two groups which are oppositely arranged, one group of iron core sections are arranged along the vertical direction to adjust the upper and lower positions of the rotor assembly, and the other group of iron core sections are arranged along the horizontal direction to adjust the horizontal position of the rotor assembly; or, four iron core sections evenly arrange along the circumference of radial iron core, and two iron core sections are located the upside, and two iron core sections are located the downside, are located two iron core sections of upside and are located two iron core sections of downside and are symmetrical about the horizontal plane.

Preferably, the axial magnetic field control parts at the two ends of the rotor assembly are separately designed and independently controlled.

Preferably, the axial magnetic field control portion and the radial magnetic field control portion are independent of each other.

Preferably, the magnetic suspension bearing further comprises a housing, and the axial magnetic field control part, the radial magnetic field control part and the permanent magnet are fixedly installed in the housing.

According to another aspect of the present application, there is provided an electric machine comprising a magnetic bearing, the magnetic bearing being the magnetic bearing described above.

According to another aspect of the present application, there is provided a compressor comprising a magnetic bearing, which is the above-mentioned magnetic bearing.

According to another aspect of the present application, there is provided an air conditioner comprising a magnetic suspension bearing, which is the above magnetic suspension bearing.

The application provides a magnetic suspension bearing, including axial magnetic field control portion, radial magnetic field control portion and rotor subassembly, the both ends of radial magnetic field control portion are provided with axial magnetic field control portion respectively, the rotor subassembly includes rotor core, axial magnetic field control portion includes the axial control end that sets up relatively with rotor core's terminal surface, the axial control end is provided with the axial control winding, radial magnetic field control portion includes the radial control end that sets up relatively with rotor core's outer peripheral face, the radial control end is provided with the radial control winding, be provided with the permanent magnet between the axial magnetic field control portion at both ends and the radial magnetic field control portion respectively, the axial magnetic field control portion that the permanent magnet held for this permanent magnet place provides bias magnetic field, the permanent magnet at both ends provides bias magnetic field for radial magnetic field control portion jointly. The magnetic suspension bearing of the embodiment of the application, make the permanent magnet separation design that provides the bias magnetic field, the permanent magnet of one end provides the axial bias magnetic field for the axial control winding of this end, the permanent magnet of the other end provides the axial bias magnetic field for the axial control winding of the other end, two permanent magnets provide radial bias magnetic field jointly, can avoid the axial control magnetic field mutual interference problem that the too big axial control magnetic field leads to in front and back axial control magnetic field, make the separation of front and back axial control magnetic field, mutual noninterference, axial control system is independent around realizing, control logic is simplified, improve system stability, furthermore, the axial output of axial magnetic field control portion is not restricted by the permanent magnet, under the performance condition that satisfies control winding, magnetic material, sustainable increase axial load.

Drawings

FIG. 1 is a schematic perspective cross-sectional view of a magnetic suspension bearing according to an embodiment of the present application;

FIG. 2 is an exploded view of a magnetic bearing according to an embodiment of the present application;

FIG. 3 is a schematic diagram of a magnetic structure of a magnetic suspension bearing according to an embodiment of the present application;

FIG. 4 is a schematic view of the magnetic structure in the direction A-A of FIG. 3;

fig. 5 is a schematic view of a magnetic structure of a magnetic suspension bearing in the related art.

The reference numerals are represented as:

1. a permanent magnet; 2. a rotor core; 3. an axial control winding; 4. a radial control winding; 5. an axial core; 6. a magnetic conductive plate; 7. an annular projection; 8. an annular wire groove; 9. a radial iron core; 10. a magnetic conductive ring; 11. a radial tooth; 12. a magnetic shield plate; 13. a magnetism isolating ring; 14. a magnetic conductive bulge; 15. an avoidance groove; 16. a housing.

Detailed Description

Referring to fig. 1 to 4 in combination, according to an embodiment of the present application, a magnetic bearing includes an axial magnetic field control portion, radial magnetic field control portion and rotor subassembly, the both ends of radial magnetic field control portion are provided with axial magnetic field control portion respectively, the rotor subassembly includes rotor core 2, axial magnetic field control portion includes the axial control end that sets up relatively with rotor core 2's terminal surface, the axial control end is provided with axial control winding 3, radial magnetic field control portion includes the radial control end that sets up relatively with rotor core 2's outer peripheral face, the radial control end is provided with radial control winding 4, be provided with permanent magnet 1 between the axial magnetic field control portion at both ends and the radial magnetic field control portion respectively, permanent magnet 1 provides bias magnetic field for the axial magnetic field control portion of this permanent magnet 1 place end, permanent magnet 1 at both ends provides bias magnetic field for radial magnetic field control portion jointly.

The magnetic suspension bearing of the embodiment of the application, make permanent magnet 1 separation design that provides the bias magnetic field, the permanent magnet 1 of one end provides the axial bias magnetic field for the axial control winding 3 of this end, the permanent magnet 1 of the other end provides the axial bias magnetic field for the axial control winding 3 of the other end, two permanent magnets 1 provide radial bias magnetic field jointly, can avoid the axial control magnetic field mutual interference problem that the too big axial control magnetic field leads to in front and back axial control magnetic field, make the separation of front and back axial control magnetic field, mutual noninterference, realize that front and back axial control system is independent, simplify control logic, improve system stability, furthermore, the axial output of axial magnetic field control portion is not restricted by permanent magnet 1, under the performance condition that satisfies control winding, magnetic material, sustainable increase axial load.

This magnetic suspension bearing utilizes axial magnetic field control portion to control the axial displacement of rotor subassembly, utilize radial magnetic field control portion to control the radial displacement of rotor subassembly, make simultaneously that the axial magnetic field control portion and the radial magnetic field control portion that are located the same end of rotor subassembly share a permanent magnet 1, utilize a permanent magnet 1 to form radial offset magnetic field and axial offset magnetic field simultaneously, the integrated design of axial and radial displacement control of magnetic suspension bearing has been realized, make motor rotor subassembly's radial and axial stress position integrated, consequently, can effectively shorten the axial length of rotor subassembly, simplify the rotor structure, improve the pivot natural frequency, promote the limit speed of rotor subassembly.

In this embodiment, since the axial magnetic field control part and the radial magnetic field control part share one permanent magnet 1, the permanent magnet 1 can provide the axial and radial bias magnetic fields at the same time, so that the usage amount of the permanent magnet can be saved, the utilization efficiency of the permanent magnet 1 can be improved, and the cost can be saved. In addition, because the number of the permanent magnets 1 is reduced, the occupied space of the permanent magnets can be saved, the miniaturization design of the magnetic suspension bearing is further realized, and the structure of the magnetic suspension bearing is more compact.

In this embodiment, the axial control winding 3 is sleeved outside the rotating shaft and is arranged at the axial control end, and the axial magnetic field control part forms an axial control magnetic field with the rotor core 2 through the axial control winding 3, so that the rotor core 2 can be utilized to provide thrust action, an independent thrust bearing is not required to be arranged, the structure of the rotating shaft can be simplified, and the reliability and stability of the operation of the rotating shaft can be improved.

Generally speaking, the radial displacement of rotor subassembly is adjusted mainly for vertical direction and horizontal direction, therefore, radial magnetic field control portion also designs for four parts correspondingly, and upper and lower two parts are a set of, realizes adjusting rotor subassembly's vertical direction displacement, and two parts are a set of about, realize adjusting rotor subassembly's horizontal direction displacement to make magnetic suspension bearing's displacement adjust nimble convenient.

In the embodiment of this application, axial magnetic field control portion, permanent magnet 1 and radial magnetic field control portion combine together, be equivalent to between the three and made up into a whole, consequently be equivalent to the integrated structure who has formed journal bearing and axial bearing, the atress position also forms the structure of integrating, effectively reduce the three and at the ascending length that occupies of rotor subassembly axial direction, and then can shorten rotor subassembly axial length, simplify and change the subassembly structure of group, improve the pivot natural frequency, promote rotor limit speed.

In one embodiment, the permanent magnet 1 is disposed on the outer peripheral side of the axial magnetic field control portion, and the radial magnetic field control portion is disposed on the outer peripheral side of the permanent magnet 1. In this embodiment, because axial magnetic field control portion, permanent magnet 1 and radial magnetic field control portion arrange along radially in proper order, and laminate each other between the three, consequently can rationally carry out the overall arrangement to the position between the three, effectively reduce the three and at rotor subassembly axial direction ascending length that occupies, and then can further shorten rotor subassembly axial length, simplify and change the subassembly structure, improve the pivot natural frequency, promote rotor limit speed.

In one embodiment, the axial magnetic field control portion, the permanent magnet 1 and the radial magnetic field control portion may also be sequentially arranged along the axial direction, and closely attached together, so as to reduce the occupied length of the three in the axial direction of the rotor assembly to a certain extent.

In one embodiment, the axial magnetic field control portion further includes an axial core 5, the axial core 5 is disposed opposite to an end surface of the rotor core 2, and the axial control winding 3 is disposed at an end of the axial core 5 facing the rotor core 2. The end face, facing the rotor core 2, of the axial core 5 is provided with an annular wire slot 8, the axial control winding 3 is installed in the annular wire slot 8, and a magnetic conduction channel can be formed on the side wall of the annular wire slot 8, so that magnetic force lines reach the rotor core 2 through the axial core 5 to form axial thrust, and further the axial position of the rotor assembly can be adjusted.

In one embodiment, the axial core 5 includes a magnetic conductive plate 6, the magnetic conductive plate 6 is provided with an annular protrusion 7 protruding toward the rotor core 2, an annular slot 8 is provided on the annular protrusion 7, the axial control winding 3 is disposed in the annular slot 8, and the permanent magnet 1 is disposed on the outer circumferential side of the magnetic conductive plate 6. In this embodiment, the magnetic conductive plate 6 is used to cooperate with the permanent magnet 1 to form a magnetic conductive path in a radial direction, so that an axial bias magnetic field generated by the permanent magnet 1 can reach the annular protrusion 7 through the magnetic conductive plate 6 and then reach the rotor core 2 through the annular protrusion 7, thereby forming a closed magnetic circuit structure, and adjusting an axial position of the rotor assembly. Through setting up annular arch 7, can utilize the structure of annular arch 7 to carry out regularly to the magnetic line of force for produced axial effort is more concentrated between axial iron core 5 and rotor core 2, and the action position is more accurate, can guarantee rotor core 2's both ends axial action position's uniformity more conveniently. In addition, the inner and outer ring side walls of the annular wire groove 8 on the annular protrusion 7 can form an inner layer and an outer layer of magnetic conduction channels, so that a magnetic circuit can be separated, and the axial control magnetic field and the radial control magnetic field are further independent and mutually noninterfere.

In one embodiment, the annular projection 7 is formed with a first axial control magnetic pole and a second axial control magnetic pole, and the control magnetic field generated by the axial magnetic field control portion forms an axial control magnetic field via the first axial control magnetic pole, the rotor core 2, and the second axial control magnetic pole.

In the embodiment, the magnetic suspension bearing provides bias magnetic fields for the left axial bearing and the right axial bearing through the permanent magnets 1 on the two sides of the rotor core 2 respectively, the permanent magnets 1 on the two sides provide the bias magnetic fields for the radial bearing together, and the left axial control magnetic field and the right axial control magnetic field are opposite and do not interfere with each other.

In one embodiment, the radius of the first axial control pole is smaller than the radius of the second axial control pole, the air gap distance between the first axial control pole and the rotor core 2 in the axial direction is L1, the air gap distance between the second axial control pole and the rotor core 2 is L2, and L1 is greater than L2.

In the present embodiment, the annular projection 7 comprises an inner ring forming the first axial control pole and an outer ring forming the second axial control pole.

The distance between the second axial control magnetic pole and the rotor iron core 2 is smaller than that between the first axial control magnetic pole and the permanent magnets 1 on the two sides, a bias magnetic field is generated, a loop is formed only by the second axial control magnetic pole, the rotor iron core 2, the radial iron core and the magnetic conduction ring 10, bias magnetic flux is formed at an axial air gap between the second axial control magnetic pole and the rotor iron core 2, the bias magnetic flux at the air gap is adjusted by the axial control magnetic field, and the axial suspension control of the rotor is realized.

The second axial control magnetic pole is not consistent with the first axial control magnetic pole in height, so set up the air gap distance of first axial control magnetic pole and rotor core 2 to be greater than the air gap distance of second axial control magnetic pole and rotor core 2, can avoid when rotor subassembly and axial control magnetic pole are closely laminated, the atmospheric pressure of axial control magnetic pole winding wire inslot is undersized, and external atmospheric pressure is too big, the rotor subassembly is difficult to the problem of separation with the magnetic pole.

In one embodiment, the radius of the second axial control pole is smaller than the radius of the rotor core 2.

The radius of second axial control magnetic pole is less than rotor core 2, but the area of exerting oneself of axial control magnetic pole is utilized to the make full use of, improves the material utilization ratio of product, if second axial control magnetic pole is too greater than rotor core 2, and with radial iron core parallel and level, then can have radial iron core to bear axial load, radial iron core lamination suffers the destruction risk.

In one embodiment, the radial magnetic field control portion includes a radial iron core 9 and magnetic conductive rings 10 disposed at two axial ends of the radial iron core 9, the magnetic conductive rings 10 are disposed on the outer peripheral side of the permanent magnet 1, the radial iron core 9 is sleeved outside the rotor iron core 2, the radial iron core 9 includes radial teeth 11, and the radial control winding 4 is wound on the radial teeth 11. In this embodiment, the magnetic conductive ring 10 cooperates with the permanent magnet 1 to form a magnetic conductive channel of a radial bias magnetic field, so as to guide magnetic lines generated by the permanent magnet 1 to the radial iron core 9, and then reach the rotor iron core 2 through the radial iron core 9 to form a radial acting force, and the radial control winding 4 is wound on the radial teeth 11 to form a control magnetic field, so as to adjust the magnitude of the radial acting force, thereby achieving the radial position adjustment of the rotor assembly.

For the radial bearing, mainly used for adjusting the radial position of the rotor assembly, therefore, it is necessary to ensure that the flow of the magnetic lines of force is concentrated in the radial direction, and the magnetic lines of force generated by the permanent magnet 1 will be divided into two parts after reaching the radial iron core 9, a part of the magnetic lines of force will reach the rotor iron core 2 from the radial teeth 11 to form a radial acting force, and the other part of the magnetic lines of force will flow along the circumferential direction of the radial iron core 9, and the magnetic lines of force flowing along the circumferential direction of the radial iron core 9 in different areas will cancel each other due to the opposite directions, which will not only affect the permanent magnet 1 to generate an effective radial bias magnetic field, but also will hardly ensure that the radial iron core 9 generates an effective radial action, and will hardly form an effective radial adjustment effect on the rotor assembly, therefore, in order to avoid this, the radial iron core 9 needs to be segmented, and magnetic force lines between adjacent iron core sections are cut off, so that the magnetic force lines are concentrated on the radial teeth 11, an effective radial magnetic field is formed, and effective radial adjustment is formed on the rotor assembly.

In one embodiment, the radial core 9 is divided into a plurality of core segments along the circumferential direction, and the plurality of core segments are magnetically isolated by a magnetic isolation structure. In this embodiment, each core segment includes three radial teeth 11, and the width of three radial teeth 11 is different, and wherein the tooth width of the radial tooth 11 located in the middle position is greater than or equal to the sum of the widths of two radial teeth 11 on both sides, so as to ensure that three radial teeth 11 can form two completed closed magnetic circuits, provide a larger radial acting force, and ensure that the radial tooth 11 in the middle has a sufficient width, and can accommodate sufficient magnetic lines of force to pass through, thereby improving the utilization rate of the permanent magnet 1. As a preferred embodiment, the width of the middle radial tooth 11 is the sum of the widths of the two radial teeth 11 on both sides, and the widths of the two radial teeth 11 on both sides are equal, so that the balance of the radial forces of the core segments of the radial core 9 can be further improved.

In one embodiment, the magnetic isolation structure comprises magnetic isolation plates 12, and the magnetic isolation plates 12 are arranged between two adjacent iron core sections at intervals. In this embodiment, the magnetic isolation plate 12 is a flat plate structure, and the shape of the plate surface is consistent with the cross-sectional shape of the yoke portion of the core segment, so that a good magnetic field isolation effect can be formed, and meanwhile, the core segments can still be a complete annular core structure after being combined together.

In one embodiment, the core segment and the magnetism isolating plate 12 may be fixed by adhesion, or may be fixed by other means, in which case, the magnetic conductive ring 10 may directly contact with the core segment to conduct the magnetic force lines. In order to ensure that the transmission position of the magnetic force line of the magnetic conductive ring 10 is accurate and a plurality of closed magnetic circuits can be effectively formed, preferably, the end part of the magnetic conductive ring 10 facing the core segment is provided with a plurality of magnetic conductive protrusions 14, the magnetic conductive protrusions 14 are arranged in one-to-one correspondence with the core segments, the circumferential width of each magnetic conductive protrusion 14 is not greater than the circumferential width of the radial tooth 11 in the middle of each core segment, and each magnetic conductive protrusion 14 is arranged corresponding to the radial tooth 11 in the middle.

In one embodiment, the magnetism isolating structure further comprises a magnetism isolating ring 13, the magnetism isolating ring 13 is arranged between the magnetic conducting ring 10 and the radial iron core 9 at intervals, the magnetism isolating plate 12 is arranged on the magnetism isolating ring 13, an avoiding groove 15 is arranged on the magnetism isolating ring 13, a magnetism conducting protrusion 14 is arranged on the magnetic conducting ring 10, the magnetism conducting protrusion 14 is arranged in the avoiding groove 15, and a magnetism conducting channel is formed between the magnetic conducting ring 10 and the radial iron core 9 through the magnetism conducting protrusion 14. In this embodiment, the magnetism isolating ring 13 can isolate the magnetic force lines between the magnetism conducting ring 10 and the radial iron core 9, the radial bias magnetic field generated by the permanent magnet 1 can only reach the radial iron core 9 through the magnetism conducting protrusion 14 to generate a closed magnetic circuit, the magnetism isolating ring 13 is arranged, the avoiding groove 15 is arranged on the magnetism isolating ring 13, the magnetism conducting protrusion 14 penetrating through the avoiding groove 15 is arranged on the magnetism conducting ring 10, the flowing direction of the magnetic force lines can be accurately controlled, and the radial adjusting effect of the radial iron core 9 can be more accurately controlled.

In one embodiment, the magnetism isolating plates 12 are uniformly arranged at intervals along the circumferential direction of the magnetism isolating ring 13, the avoiding grooves 15 are uniformly arranged at intervals along the circumferential direction of the magnetism isolating ring 13, and the magnetism isolating plates 12 and the avoiding grooves 15 are alternately arranged along the circumferential direction of the magnetism isolating ring 13. The structural design can avoid conflict between the arrangement position of the avoiding groove 15 and the arrangement position of the magnetism isolating ring 13, and the reasonability of arrangement of the avoiding groove 15 and the magnetism isolating plate 12 along the circumferential position of the magnetism isolating ring 13 is ensured, so that the radial position of the rotor assembly is more effectively adjusted.

In one embodiment, the magnetism isolating plate 12 and the magnetism isolating ring 13 are integrally formed, so that the integrally formed structure between the magnetism isolating plate 12 and the magnetism isolating ring 13 can be utilized to reduce the processing difficulty and improve the processing efficiency, and the structural strength between the magnetism isolating plate 12 and the magnetism isolating ring 13 can be effectively ensured. In addition, the magnetism isolating plate 12 is fixed on the magnetism isolating ring 13, so that the iron core sections can be conveniently installed and fixed, and the magnetism isolating ring 13 is used for providing an installation structure for the radial iron core.

In one embodiment, the avoiding groove 15 is located at the middle position of two adjacent magnetism isolating plates 12 along the circumferential direction, so that the magnetism isolating plates 12 and the magnetism conducting protrusions 14 are uniformly arranged along the circumferential direction of the magnetism isolating ring 13, thereby uniformly distributing the magnetism isolating parts and the magnetism conducting parts, and further ensuring that the radial force applied by the radial iron core 9 to the rotor iron core 2 is uniformly distributed along the circumferential direction.

In one embodiment, the radial core 9 is divided into four core segments along the circumferential direction, and the four core segments are divided into two oppositely arranged groups, wherein one group of the core segments is arranged along the vertical direction to adjust the up-down position of the rotor assembly, and the other group of the core segments is arranged along the horizontal direction to adjust the horizontal position of the rotor assembly. The structure of four iron core sections is the same to make four iron core sections be evenly distributed structure along circumference, every iron core section is when not exerting radial control magnetic field, and the radial effort to rotor core 2 is the same under the same electric current effect, can improve the uniformity of atress effect, so, radial control magnetic field is more accurate to rotor core 2's atress control, and radial position adjusts more accurately and reliably.

In an embodiment, four iron core sections evenly arrange along the circumference of radial iron core, and two iron core sections are located the upside, two iron core sections are located the downside, two iron core sections that are located the upside with be located two iron core sections of downside about the horizontal plane symmetry, because four iron core sections are along circumference evenly distributed, consequently, two iron core sections that are located the first end of the horizontal diameter of radial iron core and two iron core sections that are located the horizontal diameter second end of radial iron core are also about vertical plane symmetry, thereby make two liang of a set of four iron core sections, under the same condition of the electric current that lets in, can exert the effort that same size opposite direction to rotor core 2, make rotor core 2 keep at the intermediate position, the precision that radial iron core adjusted the radial position of rotor core 2 has been improved.

In the embodiment, each radial iron core section forms an E-shaped magnetic pole, so that the radial horizontal and radial vertical control systems are independent and do not interfere with each other, the control logic is simplified, and the reliability and stability of the suspension system are improved.

In one embodiment, the permanent magnet 1 is an annular structure, and is sleeved outside the magnetic conduction plate 6 of the axial iron core 5 and in interference fit with the magnetic conduction plate 6, and the magnetic conduction ring 10 is sleeved outside the permanent magnet 1 and in interference fit with the permanent magnet 1, so that the axial magnetic field control part, the permanent magnet 1 and the radial magnetic field control part form an integral structure fixed together.

The two ends of the rotor component are respectively provided with an axial magnetic field control part, and the axial magnetic field control parts at the two ends of the rotor component are designed separately and independently controlled. The front and the rear axial bearings are separately designed and provided with independent processing systems, so that the limit load of the axial bearings is not limited by the magnetic field of the permanent magnet 1, and the axial output can be continuously improved according to requirements under the performance conditions of the axial control winding 3 and the magnetic conductive material, thereby reducing the material cost of the permanent magnet and improving the performance of the magnetic suspension bearing.

In one embodiment, the axial magnetic field control part and the radial magnetic field control part are independent from each other and do not interfere with each other, share one permanent magnet 1, effectively shorten axial occupied space, reduce the number of parts and save material cost.

In this embodiment, the front end and the rear end of the rotating shaft are respectively provided with an axial magnetic field control part and a radial magnetic field control part which are independently controlled, so that the axial direction position adjustment can be realized by using the axial magnetic field control part, and the adjustment of multiple degrees of freedom in the vertical direction, the horizontal direction and the like can be realized by using the radial magnetic field control part, thereby realizing the three-degree-of-freedom suspension control of the motor rotor.

In one embodiment, the magnetic suspension bearing further comprises a housing 16, and the axial magnetic field control part, the radial magnetic field control part and the permanent magnet 1 are fixedly installed in the housing 16. In this embodiment, the casing 16 includes an end cover and an outer cylinder, wherein the end cover is provided with a shaft hole for the spindle to pass through, the axial iron core 5, the permanent magnet 1 and the magnetic conductive ring 10 are all matched with the end cover to form an axial stop, and the outer cylinder is sleeved outside the magnetic conductive ring 10, the magnetic isolation ring 13 and the radial iron core 9 and can form installation and fixation for the magnetic conductive ring 10, the magnetic isolation ring 13 and the radial iron core 9. The aperture of the inner hole of the end cover is smaller than the outer diameter of the magnetic conduction plate 6 of the axial iron core 5, the axial position of the magnetic conduction plate 6 can be limited through the end cover, the magnetic conduction plate 6 is prevented from being separated from the shaft hole of the end cover, the axial length of the outer cylinder is larger than or equal to the total axial length of the magnetic conduction ring 10, the magnetism isolating ring 13 and the radial iron core 9 after combination, the magnetic conduction ring 10, the magnetism isolating ring 13 and the radial iron core 9 can be contained, and the shell 16 can be used for protecting the magnetic conduction ring 10, the magnetism isolating ring 13 and the radial iron core 9.

Because the axial bearing and the radial bearing are both installed and fixed in the shell 16, an axial-radial integrated magnetic suspension structure with stable structure can be formed through the shell 16, and the structural stability is better.

In this embodiment, the housing 16, the axial bearing, the permanent magnet 1 and the radial bearing at the front end form a front bearing structure, the housing 16, the axial bearing, the permanent magnet 1 and the radial bearing at the rear end form a rear bearing structure, the two bearing structures are separately designed and are independent from each other, and the flexibility of adjusting the position of the rotor core can be further improved.

The assembly process of the magnetic suspension bearing is as follows:

the magnetic conductive ring 10 is fixed inside the casing 16 in a shrink fit and screw connection manner, so as to realize radial and axial positioning. The axial control winding 3 is embedded in the groove of the axial iron core 5 in a manner of encapsulation and self-tapping threaded connection, so that the axial and radial positioning of the axial control winding 3 is realized, and an axial bearing assembly is formed. The radial control winding 4 is wound on the main pole of the radial iron core 9 and fixed in a winding and paint dipping mode to form a radial bearing assembly, and the radial bearing assembly is embedded on the magnetic isolation structure to form a radial bearing assembly. The shell 16 is heated and expanded, the axial bearing, the permanent magnet 1 and the radial bearing are sequentially arranged in the shell 16, the radial positioning of the bearing assembly is realized, the axial positioning of the bearing assembly is realized through threaded connection, the front axial-radial bearing assembly is formed, and the same installation process is carried out on the rear axial-radial bearing assembly. The front axial-radial bearing assembly and the rear axial-radial bearing assembly are respectively installed at two ends of the rotor core 2, and the installation of the novel thrust-bearing-free five-degree-of-freedom magnetic suspension bearing is achieved.

The operation principle of the magnetic suspension bearing according to the embodiment of the present application will be described with reference to fig. 1 to 4.

As shown in fig. 1 and 2, the ring-shaped permanent magnet 1 generates a bias magnetic field, and forms a closed loop by the upper magnetic pole of the axial iron core 5, the rotor iron core 2, the radial iron core 9, and the magnetic conductive ring 10, thereby forming an axial-radial bias magnetic field. The axial-radial bias magnetic field forms an axial bias magnetic flux in the air gap between the rotor core 2 and the magnetic pole on the axial core 5, and forms a radial bias magnetic flux in the air gap between the rotor core 2 and the radial core 9. The axial control winding 3 is connected with a control current to form a control magnetic field, and the control magnetic field and the rotor iron core 2 form a closed loop through the upper and lower magnetic poles of the axial iron core 5 to form an axial control magnetic field, so that the magnetic density in an axial air gap is adjusted, and the axial suspension control of the rotor iron core 2 is realized. The radial control winding 4 is connected with a control current to generate a control magnetic field, the control magnetic field forms a closed loop through the main magnetic pole of the radial iron core 9, the rotor iron core 2 and the auxiliary magnetic poles at two sides of the radial iron core 9 to form a radial control magnetic field, the magnetic density at the magnetic pole gap between the radial iron core 9 and the rotor iron core 2 is adjusted, the suspension control of two radial degrees of freedom of the rotor assembly is realized, and the three-degree-of-freedom suspension of the motor rotor is realized. The radial bearing and the axial iron core are integrated, and the radial-axial stress position of the motor rotor is integrated, so that the axial length of the rotor is effectively shortened, the structure of the rotor is simplified, the inherent frequency of a rotating shaft is improved, and the limit rotating speed of the rotor is improved. The front axial iron core and the rear axial iron core are separated and do not interfere with each other, the axial output force is not limited by the permanent magnet, and the axial load can be continuously increased under the condition of meeting the performance conditions of the control winding and the magnetic conduction material.

When the rotating shaft is located at the axial balance position, the magnetic densities of the gaps between the rotor iron core 2 and the left and right axial iron cores 5 are the same, and the rotor is subjected to balanced load. When the rotating shaft bears leftward impact load, the rotating shaft deflects leftward, the gap between the rotor core 2 and the left axial core 5 is reduced, the left biased flux density is increased, the right gap is increased, the right biased flux density is reduced, the axial suction force of the left axial core 5 to the rotor core 2 is greater than that of the right axial core 5, no external control is performed, and the rotating shaft continuously deflects leftward. The left side control current is reduced, the right side control current is increased, the bias flux density at the left air gap and the right air gap is adjusted, the flux density in the right air gap is larger than that in the left air gap, the rotating shaft deflects to the right side, if the axial leftward load is larger, the left side control current is reduced to 0, the reduction is stopped, the right side control current can be continuously increased until the axial load is balanced, and therefore the rotating shaft deflects to the right side until the balance position, and the suspension control of the axial degree of freedom is achieved.

When the rotating shaft is located at the radial balance position, the gaps between the rotor core 2 and the upper and lower magnetic poles of the radial core 9 are the same, the magnetic densities of the bias magnetic field in the gaps are the same, the attractive forces of the upper and lower magnetic poles of the radial core 9 to the rotor core 2 are the same, and the rotor core 2 is continuously located at the balance position. When the rotating shaft bears vertical downward impact load, the rotating shaft deflects downward, the gap on the upper side is enlarged, the gap on the lower side is reduced, the magnetic density of the gap on the lower side is larger than that of the gap on the upper side, the downward suction force of the radial iron core 9 to the rotor iron core 2 is larger than the upward suction force, no external regulation is carried out, and the rotating shaft continuously deflects downward. The radial control winding 4 is connected with control current to generate a control magnetic field, the magnetic density in the gap at the upper side is increased, the magnetic density in the gap at the lower side is reduced, the upward suction force of the radial iron core 9 to the rotor iron core 2 is larger than the downward suction force, the motor rotor deflects upwards until the balance position, and the suspension control of the front radial degree of freedom and the back radial degree of freedom is realized.

According to an embodiment of the application, the motor comprises a magnetic bearing, which is the magnetic bearing described above.

According to an embodiment of the present application, the compressor comprises a magnetic bearing, which is the above-mentioned magnetic bearing.

According to an embodiment of the present application, the air conditioner includes a magnetic bearing, which is the above-mentioned magnetic bearing.

It is readily understood by a person skilled in the art that the advantageous ways described above can be freely combined, superimposed without conflict.

The present invention is not intended to be limited to the particular embodiments shown and described, but is to be accorded the widest scope consistent with the principles and novel features herein disclosed. The foregoing is only a preferred embodiment of the present application, and it should be noted that, for those skilled in the art, several modifications and variations can be made without departing from the technical principle of the present application, and these modifications and variations should also be considered as the protection scope of the present application.

Claims

1. The magnetic suspension bearing is characterized by comprising an axial magnetic field control part, a radial magnetic field control part and a rotor assembly, wherein the axial magnetic field control part is arranged at each of two ends of the radial magnetic field control part respectively, the rotor assembly comprises a rotor core (2), the axial magnetic field control part comprises an axial control end which is arranged opposite to the end surface of the rotor core (2), an axial control winding (3) is arranged at each axial control end, the radial magnetic field control part comprises a radial control end which is arranged opposite to the outer peripheral surface of the rotor core (2), a radial control winding (4) is arranged at each radial control end, permanent magnets (1) are arranged between the axial magnetic field control part and the radial magnetic field control part at each of two ends respectively, and the permanent magnets (1) provide bias magnetic fields for the axial magnetic field control part at the position of the permanent magnets (1), the permanent magnets (1) at the two ends provide bias magnetic fields for the radial magnetic field control part together.

2. Magnetic suspension bearing according to claim 1, characterized in that the permanent magnet (1) is arranged on the outer circumference side of the axial magnetic field control section and the radial magnetic field control section is arranged on the outer circumference side of the permanent magnet (1).

3. Magnetic bearing according to claim 1, characterized in that the axial magnetic field control part further comprises an axial core (5), the axial core (5) being arranged opposite to an end face of the rotor core (2), the axial control winding (3) being arranged at an end of the axial core (5) facing the rotor core (2).

4. Magnetic suspension bearing according to claim 3, characterized in that the axial core (5) comprises a magnetic conducting plate (6), the magnetic conducting plate (6) is provided with an annular protrusion (7) protruding towards the rotor core (2), an annular slot (8) is provided on the annular protrusion (7), the axial control winding (3) is arranged in the annular slot (8), and the permanent magnet (1) is arranged at the outer circumferential side of the magnetic conducting plate (6).

5. Magnetic bearing according to claim 4, characterized in that the annular protrusion (7) is formed with a first axial control pole and a second axial control pole, the control magnetic field generated by the axial magnetic field control part forming an axial control magnetic field through the first axial control pole, the rotor core (2) and the second axial control pole.

6. Magnetic bearing according to claim 5, characterized in that the radius of the first axial control pole is smaller than the radius of the second axial control pole, the air gap distance of the first axial control pole to the rotor core (2) in the axial direction is L1, the air gap distance of the second axial control pole to the rotor core (2) is L2, and L1 is larger than L2.

7. Magnetic bearing according to claim 6, characterized in that the radius of the second axial control pole is smaller than the radius of the rotor core (2).

8. The magnetic suspension bearing according to claim 1, wherein the radial magnetic field control portion comprises a radial iron core (9) and magnetic conductive rings (10) located at two axial ends of the radial iron core (9), the magnetic conductive rings (10) are arranged on the outer peripheral side of the permanent magnet (1), the radial iron core (9) is sleeved outside the rotor iron core (2), the radial iron core (9) comprises radial teeth (11), and the radial control winding (4) is wound on the radial teeth (11).

9. Magnetic suspension bearing according to claim 8, characterized in that the radial core (9) is divided circumferentially into a plurality of core segments, which are magnetically isolated from each other by a magnetic isolation structure.

10. Magnetic suspension bearing according to claim 9, characterized in that the magnetic shielding structure comprises magnetic shielding plates (12), and the magnetic shielding plates (12) are arranged between two adjacent core segments at intervals.

11. The magnetic suspension bearing according to claim 10, wherein the magnetism isolating structure further comprises a magnetism isolating ring (13), the magnetism isolating ring (13) is disposed between the magnetic conductive ring (10) and the radial core (9) at intervals, the magnetism isolating plate (12) is disposed on the magnetism isolating ring (13), an avoiding groove (15) is disposed on the magnetism isolating ring (13), a magnetic conductive protrusion (14) is disposed on the magnetic conductive ring (10), the magnetic conductive protrusion (14) is disposed in the avoiding groove (15), and the magnetic conductive ring (10) forms a magnetic conductive path with the radial core (9) through the magnetic conductive protrusion (14).

12. Magnetic suspension bearing according to claim 11, wherein the magnetism isolating plates (12) are uniformly spaced along the circumferential direction of the magnetism isolating ring (13), the avoiding grooves (15) are uniformly spaced along the circumferential direction of the magnetism isolating ring (13), and the magnetism isolating plates (12) and the avoiding grooves (15) are alternately arranged along the circumferential direction of the magnetism isolating ring (13).

13. Magnetic suspension bearing according to claim 11, characterized in that the magnetism isolating plate (12) is integrally formed with the magnetism isolating ring (13).

14. Magnetic suspension bearing according to claim 12, characterized in that the avoidance slot (15) is located circumferentially in the middle of two adjacent magnetic shield plates (12).

15. Magnetic suspension bearing according to claim 9, characterized in that the radial core (9) is divided circumferentially into four core segments, which are divided into two oppositely arranged groups, one of which is arranged vertically to adjust the up-down position of the rotor assembly, and the other of which is arranged horizontally to adjust the horizontal position of the rotor assembly; or, four the iron core sections are evenly arranged along the circumference of the radial iron core, and two the iron core sections are located at the upper side, two the iron core sections are located at the lower side, two the iron core sections at the upper side and two the iron core sections at the lower side are symmetrical relative to the horizontal plane.

16. Magnetic bearing according to any of claims 1 to 15, wherein the axial magnetic field control sections at both ends of the rotor assembly are designed separately, independently controlled.

17. Magnetic bearing according to any of claims 1 to 15, characterized in that the axial magnetic field control section and the radial magnetic field control section are independent of each other.

18. Magnetic bearing according to any of claims 1 to 15, characterized in that the magnetic bearing further comprises a housing (16), the axial magnetic field control part, the radial magnetic field control part and the permanent magnets (1) being fixedly mounted within the housing (16).

19. An electrical machine comprising a magnetic bearing as claimed in any one of claims 1 to 18.

20. A compressor, characterized by comprising a magnetic bearing as claimed in any one of claims 1 to 18.

21. An air conditioner, characterized in that, comprises a magnetic suspension bearing, wherein the magnetic suspension bearing is the magnetic suspension bearing of any one of claims 1 to 18.