CN114992240A

CN114992240A - Magnetic suspension bearing and compressor

Info

Publication number: CN114992240A
Application number: CN202210582918.6A
Authority: CN
Inventors: 郭伟林; 龚高; 张超
Original assignee: Gree Electric Appliances Inc of Zhuhai
Current assignee: Gree Electric Appliances Inc of Zhuhai
Priority date: 2022-05-26
Filing date: 2022-05-26
Publication date: 2022-09-02
Also published as: WO2023226418A1

Abstract

The invention provides a magnetic suspension bearing and a compressor, wherein the magnetic suspension bearing comprises an axial control assembly and a radial control assembly, wherein the axial control assembly comprises an axial iron core and an axial winding assembly positioned in the axial iron core, and the axial winding assembly is sleeved on the outer circumferential side of the radial control assembly. According to the invention, the occupation of the axial length space of the rotating shaft is reduced, the axial length of the rotating shaft can be designed to be shorter, the corresponding limit rotating speed of the rotating shaft can be designed to be higher, the winding can be conveniently wound, the slot filling rate of the winding can be further ensured, the structure of the winding is more compact and the volume is smaller on the premise that the performances of the bearing are the same, and meanwhile, the axial control winding positioned at the outer side can more conveniently lead out a winding lead.

Description

Magnetic suspension bearing and compressor

Technical Field

The invention belongs to the technical field of bearing manufacturing, and particularly relates to a magnetic suspension bearing and a compressor.

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 bearing is divided into three types of active type, passive type and mixed type, the active type magnetic 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 bearing realizes the suspension of the rotor by utilizing the suction force or the repulsion force between magnetic materials, and has lower rigidity and damping; the hybrid magnetic 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 suspension 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 bearing has irreplaceable advantages in the field with strict requirements on volume and power consumption, and 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 focus of research.

In the magnetic suspension bearing (taking a three-degree-of-freedom bearing as an example) in the prior art, as shown in fig. 1 and fig. 2, a permanent magnet 1 generates a radial-axial bias magnetic field 4, and bias magnetic fluxes are formed in axial and radial air gaps of an axial iron core 6, a radial iron core 3 and a bearing rotor 10. The axial control winding 7 is electrified with control current to generate an axial control magnetic field 5, and a bias magnetic field in an axial air gap is adjusted to realize the axial suspension control of the rotating shaft; the radial control winding 8 is connected with a control current to generate a radial control magnetic field 9, and the offset in a radial air gap is adjusted to realize the radial suspension control of the rotating shaft, thereby realizing three-degree-of-freedom suspension of the rotating shaft, and having the following problems: firstly, an axial control winding and a radial control winding are both assembled on a radial iron core, so that the winding is difficult to install; radial and axial windings are distributed in a concentrated mode, winding coils are too large, the axial space of the three-freedom-degree bearing is enlarged, the rotating shaft is lengthened, and the limit rotating speed is low; and the axial coil is difficult to be led out and is not easy to be led out from the inside.

Disclosure of Invention

Therefore, the magnetic suspension bearing and the compressor provided by the invention can overcome the defects that the axial winding and the radial winding in the related technology are assembled on the radial iron core to cause difficult winding installation, the winding is intensively arranged to cause overlarge winding coil, and the bearing occupies overlarge axial length space of the rotating shaft.

In order to solve the above problems, the present invention provides a magnetic suspension bearing, which includes an axial control assembly and a radial control assembly, wherein the axial control assembly includes an axial core and an axial winding assembly located inside the axial core, and the axial winding assembly is sleeved on an outer circumferential side of the radial control assembly.

In some embodiments, magnetic bearing still includes the holding ring, the axial iron core includes the first iron core casing and the second iron core casing of relative equipment, first iron core casing's inboard has first locating ring platform, the holding ring cooperation connect in on the axial one side of first locating ring platform, just the axial winding subassembly connect in the holding ring is kept away from one side of first locating ring platform, first iron core casing with second iron core casing forms right the axial winding subassembly and the axial centre gripping of holding ring.

In some embodiments, the axial winding assembly includes a bobbin support ring and an axial control winding wound in a ring groove of the bobbin support ring, and the axial winding assembly is detachably connected to the positioning ring through the bobbin support ring.

In some embodiments, the positioning ring has an outlet hole communicating along an axial direction thereof, and an outgoing wire of the axial control winding passes through the outlet hole.

In some embodiments, a lead frame is inserted into the lead hole, and the lead wire of the axial control winding passes through the central through hole of the lead frame.

In some embodiments, the radial control assembly includes a magnetic conductive ring, a radial core, and a radial control winding wound around the stator teeth of the radial core, the magnetic conductive ring is sleeved on the outer circumferential wall of the radial core, a second positioning ring table is provided on a central hole wall of the positioning ring, and the magnetic conductive ring is connected to one axial side of the second positioning ring table in a matching manner.

In some embodiments, the magnetic suspension bearing further includes two sets of magnetic steel assemblies, and the two sets of magnetic steel assemblies are respectively connected to two axial end faces of the magnetic conductive ring.

In some embodiments, the magnetic steel assembly comprises a plurality of magnetic steels and a magnetic steel positioning ring, the magnetic steel positioning ring is provided with a plurality of positioning grooves arranged along the circumferential direction of the magnetic steel positioning ring at intervals, and the plurality of magnetic steels are respectively positioned in the plurality of positioning grooves in a one-to-one correspondence manner.

In some embodiments, the magnetic steel is adhered to the axial end face of the magnetic conductive ring; and/or the magnetic steel positioning ring is detachably connected with the axial end face of the magnetic conductive ring.

In some embodiments, the magnetic suspension bearing further comprises a rotor assembly, the rotor assembly comprises a non-magnetic-conductive collar and a rotor core sleeved on the outer circumference side of the non-magnetic-conductive collar, two axial ends of the rotor core are provided with iron core shaft end baffles for axially positioning the rotor core, the iron core shaft end baffles are magnetic conductive, and an axial adjustment gap is formed between the iron core shaft section baffles and the first iron core shell or the second iron core shell adjacent to the iron core shaft section baffles; or, the rotor assembly comprises a magnetic conduction lantern ring and a rotor core sleeved on the outer circumference side of the rotor assembly, iron core shaft end baffles are arranged at two axial ends of the rotor core to axially position the rotor core, the iron core shaft end baffles conduct magnetism, and an axial adjustment gap is formed between the iron core shaft end baffles and the first iron core shell or the second iron core shell adjacent to the iron core shaft end baffles.

In some embodiments, when the rotor assembly comprises a magnetically conductive collar, a magnetic shield is further disposed between the core shaft end baffle and the corresponding end of the rotor core.

In some embodiments, the magnetic suspension bearing further includes a rotor assembly, the rotor assembly includes a rotor core, the rotor core is sleeved on the outer circumferential side of the thrust disk, the two axial ends of the rotor core are provided with iron core shaft end baffles for axially positioning the rotor core, and the iron core shaft end baffles are magnetically conductive.

In some embodiments, at least one of the two core shaft end baffles has an extension collar extending axially along it toward one side of the rotor core, the extension collar being fitted between the central through hole of the rotor core and the outer circumferential wall of the thrust disk.

In some embodiments, the rotor assembly further includes a non-magnetically conductive collar or a magnetically conductive collar, and the rotor core and the non-magnetically conductive collar or the magnetically conductive collar are positioned with the thrust disk by a positioning screw.

The invention also provides a compressor which comprises the magnetic suspension bearing.

Compared with the mode of centralized arrangement of the axial control winding and the radial control winding in the prior art, the magnetic suspension bearing and the compressor provided by the invention, the axial winding assembly in the technical scheme is positioned at the radial outer side position of the radial control assembly, so that on one hand, the axial size of the whole magnetic suspension bearing can be reduced, thereby reducing the occupation of the space of the shaft length of the rotating shaft, enabling the shaft length of the rotating shaft to be designed shorter, so that the limit rotating speed of the corresponding rotating shaft can be designed higher, on the other hand, because the axial control winding and the radial control winding are arranged inwards and outwards in the radial direction of the bearing, the winding space of the axial control winding and the radial control winding tends to be reasonable, thereby being convenient for winding, thereby ensuring the slot filling rate of the winding, so that the structure of the winding is more compact and the volume is smaller on the premise that the performances of the bearings are the same, meanwhile, the axial control winding positioned on the outer side can lead out a winding lead more conveniently.

Drawings

Fig. 1 is a schematic diagram (cross-sectional view) of the internal structure of a three-degree-of-freedom magnetic suspension bearing in the prior art, in which arrows show the flow direction of an axial control magnetic field;

FIG. 2 is a schematic flow diagram of a radial control magnetic field of the magnetic suspension bearing of FIG. 1;

FIG. 3 is a schematic diagram (cross-sectional view) of the back structure of a magnetic suspension bearing according to an embodiment of the present invention, in which arrows show the flow direction of an axial control magnetic field;

FIG. 4 is an exploded view of FIG. 2;

FIG. 5 is a partial cross-sectional view of FIG. 4 assembled;

fig. 6 to 12 are schematic structural diagrams (including axial core portion structures) of rotor assemblies in magnetic bearings in different embodiments, respectively.

The reference numbers are given as:

1. a lead frame; 2. a magnetic conductive ring; 3. a radial iron core; 4. a radial-axial bias magnetic field; 5. an axial control magnetic field; 6. an axial core; 7. an axial control winding; 8. a radial control winding; 9. a radial control magnetic field; 10. a bearing rotor; 100. an axial control assembly; 101. an axial core; 1011. a first core case; 1012. a second core housing; 102. an axial winding assembly; 1021. a framework support ring; 1022. an axial control winding; 200. a radial control assembly; 201. a radial iron core; 202. a radial control winding; 203. a magnetic conductive ring; 300. a positioning ring; 301. a lead frame; 400. a magnetic steel component; 401. magnetic steel; 402. a magnetic steel positioning ring; 500. a rotor assembly; 501. a non-magnetically conductive collar; 502. a rotor core; 503. an iron core shaft end baffle; 504. a magnetic shield plate; 505. a magnetic conductive lantern ring; 600. a thrust disk.

Detailed Description

Referring to fig. 2 to 12 in combination, according to an embodiment of the present invention, there is provided a magnetic suspension bearing, which includes an axial control assembly 100 and a radial control assembly 200, wherein the axial control assembly 100 includes an axial core 101 and an axial winding assembly 102 located inside the axial core 101, and the axial winding assembly 102 is sleeved on an outer circumferential side of the radial control assembly 200. Compared with the prior art in which the axial control windings and the radial control windings are arranged in a concentrated manner, the axial winding assembly 102 in the technical solution is located at a radially outer position of the radial control assembly 200, so that on one hand, the overall axial size of the magnetic suspension bearing can be reduced, thereby reducing the occupation of the space of the shaft length of the rotating shaft, enabling the shaft length of the rotating shaft to be designed shorter, so that the limit rotating speed of the corresponding rotating shaft can be designed higher, on the other hand, because the axial control winding and the radial control winding are arranged inwards and outwards in the radial direction of the bearing, the winding space of the axial control winding and the radial control winding tends to be reasonable, thereby being convenient for winding the windings, thereby ensuring the slot filling rate of the winding, so that the structure of the winding is more compact and the volume is smaller on the premise that the performances of the bearings are the same, meanwhile, the axial control winding positioned on the outer side can lead out a winding lead more conveniently.

In some embodiments, the magnetic suspension bearing further includes a positioning ring 300, the axial core 101 includes a first core housing 1011 and a second core housing 1012 assembled oppositely, the first core housing 1011 has a first positioning ring platform on the inner side, the positioning ring 300 is connected to one axial side of the first positioning ring platform in a matching manner, the axial winding assembly 102 is connected to one side of the positioning ring 300 away from the first positioning ring platform, the first core housing 1011 and the second core housing 1012 form an axial clamping for the axial winding assembly 102 and the positioning ring 300, it should be noted that the positioning ring 300 in this technical solution serves as an assembly carrier for the axial winding assembly 102 on one hand, so that the axial and radial positions of the axial winding assembly 102 are determined, and at the same time, it can also serve as a positioning reference for other components inside the bearing, thereby being beneficial to positioning other internal components more accurately.

As a specific implementation manner, the axial winding assembly 102 includes a frame support ring 1021 and an axial control winding 1022 wound in a ring groove of the frame support ring 1021, and the axial winding assembly 102 is detachably connected to the positioning ring 300 through the frame support ring 1021, for example, a buckle matched with the positioning ring 300 is provided on the frame support ring 1021, and the buckle is connected to the positioning ring 300 to realize positioning. In the aspect of specific assembly, the axial control winding 1022 may be wound in the annular groove of the skeleton support ring 1021, and then the integrated axial winding assembly 102 is connected to the positioning ring 300, which is convenient for assembly. In one embodiment, the positioning ring 300 has an outlet hole axially communicating therewith, the outgoing line of the axial control winding 1022 passes through the outlet hole, preferably, the lead frame 301 is inserted into the outlet hole, the outgoing line of the axial control winding 1022 passes through the central through hole of the lead frame 301, and the material of the lead frame 301 may be selected from an insulating and flexible material, so as to protect the outgoing line passing through the lead frame, prevent abrasion of the outgoing line, and improve the insulating property. It should be noted that, the axial control windings 1022 in the present invention are only provided in one set, and since they are located at the radial outer side of the radial control assembly, they can be located at the central position of the radial control assembly in the axial direction, the electromagnetic control magnetic flux generated by them can basically achieve the same output at both sides, and the magnetic leakage is less, and meanwhile, compared with the arrangement mode of two axial control windings in the prior art, the wiring process and assembly of a single control winding are convenient.

In some embodiments, the radial control assembly 200 includes a magnetic conductive ring 203, a radial core 201, and a radial control winding 202 wound around the stator teeth of the radial core 201, wherein the magnetic conductive ring 203 is sleeved on the outer circumferential wall of the radial core 201, a second positioning ring stage is provided on the central hole wall of the positioning ring 300, and the magnetic conductive ring 203 is connected to one axial side of the second positioning ring stage in a matching manner. Thus, it should be particularly noted that the installation reference of the radial iron core 201 in this technical solution is determined by the hole wall of the central through hole of the first positioning ring stage-positioning ring 300-positioning ring 203-magnetic conductive ring 203 on the axial iron core 101 (specifically, for example, the first iron core housing 1011) on the outermost side, this positioning dimensional chain does not involve magnetic steel (e.g., permanent magnet) in the prior art, the positioning matching surfaces of each component in this dimensional chain (e.g., the axial side and the ring stage circumferential wall of the first positioning ring stage, the axial side and the ring stage circumferential wall of the second positioning ring stage, the axial side and the inner and outer circumferential walls of the positioning ring, the axial side and the inner and outer circumferential walls of the magnetic conductive ring) can all be machined to ensure the form and position accuracy, so as to make the positioning of the radial iron core 201 more accurate, in the prior art, the positioning of the radial iron core 201 is related to the magnetic steel, so that the positioning accuracy error of the radial iron core 201 is large.

In some embodiments, magnetic suspension bearing still includes magnetic steel assembly 400, magnetic steel assembly 400 has two sets ofly, and is two sets of magnetic steel assembly 400 connect respectively in on two terminal surfaces of magnetic conductive ring 203's the axial, specifically speaking, magnetic steel assembly 400 includes a plurality of magnet steel 401, magnet steel holding ring 402, have on the magnet steel holding ring 402 along a plurality of constant head tanks that its circumference interval set up, it is a plurality of magnet steel 401 is in a plurality of respectively one-to-one in the constant head tank, a plurality of constant head tanks along magnet steel holding ring 402's circumference is evenly arranged, thereby makes a plurality ofly magnet steel 401's the interval of arranging is unanimous. As described above, in the present invention, the magnetic steel is adjusted to the two axial sides of the magnetic conductive ring 203 from the position of the prior art as the positioning accuracy, so that the adverse effect of the magnetic steel accuracy on the positioning accuracy of the radial core 201 does not need to be considered, that is, the radial stator core positioning structure is easier to design, manufacture and assemble because the radial stator core positioning structure does not need to be considered to avoid the permanent magnet. In addition, on the premise that the output requirements of the magnetic suspension bearings are the same, the two sides can adopt a single permanent magnet with half of specification and size in the middle, and the material cost is reduced.

The magnetic steel 401 is adhered to the axial end face of the magnetic conductive ring 203; and/or, the magnetic steel positioning ring 402 and the axial end face of the magnetic conductive ring 203 can be detachably connected, for example, the magnetic steel positioning ring 402 and the magnetic conductive ring 203 can be provided with a corresponding plug-in structure or a threaded connection structure to realize the detachable connection between the magnetic steel positioning ring and the magnetic conductive ring.

In some embodiments, the magnetic suspension bearing further includes a rotor assembly 500, the rotor assembly 500 includes a non-magnetic conductive collar 501 and a rotor core 502 sleeved on an outer circumference side of the non-magnetic conductive collar, both axial ends of the rotor core 502 are provided with core shaft end baffles 503 to axially position the rotor core 502, the core shaft end baffles 503 are magnetic conductive, and an axial adjustment gap is formed between the core shaft section baffles 503 and the first core housing 1011 or the second core housing 1012 adjacent to the core shaft section baffles 503; or, the rotor assembly 500 includes a magnetic conductive collar 505 and a rotor core 502 sleeved on an outer circumference side of the magnetic conductive collar, the rotor core 502 is provided with core shaft end baffles 503 at two axial ends thereof to axially position the rotor core 502, the core shaft end baffles 503 are magnetic conductive, and an axial adjustment gap is formed between the core shaft end baffles 503 and the first core housing 1011 or the second core housing 1012 adjacent to the core shaft end baffles 503.

In some embodiments, when the rotor assembly 500 includes a magnetically conductive collar 505, a magnetic shield 504 is further disposed between the core shaft end shield 503 and the corresponding end of the rotor core 502.

In some embodiments, the magnetic suspension bearing further includes a rotor assembly 500, the rotor assembly 500 includes a rotor core 502, the rotor core 502 is sleeved on the outer circumferential side of the thrust plate 600, two axial ends of the rotor core 502 are provided with core shaft end baffles 503 to axially position the rotor core 502, and the core shaft end baffles 503 are magnetically conductive.

In some embodiments, at least one of the two core shaft end baffles 503 has an extension collar extending axially along it toward one side of the rotor core 502, and the extension collar is fitted between the central through hole of the rotor core 502 and the outer circumferential wall of the thrust disk 600.

In some embodiments, the rotor assembly 500 further includes a non-magnetically conductive collar 501 or a magnetically conductive collar 504, and the rotor core 502 and the non-magnetically conductive collar 501 or the magnetically conductive collar 504 are positioned with the thrust disk 600 by a positioning screw.

The magnetic bearing of the invention can be assembled in particular in the following manner:

as shown in fig. 3, the radial control winding 202 is embedded in the radial iron core 201 to form a radial bearing assembly, the magnetic conductive ring 203 is heated, the radial bearing assembly is thermally sleeved in the magnetic conductive ring 203 and is tightly attached to a boss (i.e., the second positioning ring stage) on the inner wall of the magnetic conductive ring 203, after the magnetic conductive ring 203 is cooled, the radial bearing assembly is fixedly mounted, and the magnetic steel 401 is bonded to two sides of the magnetic conductive ring 203 through the strong glue to form a total radial bearing assembly; the axial control winding 1022 is wound on the inner side of the axial winding support ring (i.e. the former skeleton support ring 1021) to form an axial winding assembly, the axial control winding 1022 and the axial winding support ring are integrated through a boss buckle on the skeleton to form a total axial winding, the total axial winding is matched with the positioning ring 300 to realize the radial and axial fixation of the axial winding skeleton, meanwhile, the positioning ring 300 is made of a magnetic isolation material to prevent magnetic leakage, and an axial lead-out wire is led out through the lead skeleton 301; the front axial iron core (namely a first iron core shell 1011) is heated, the positioning ring 300, the general axial winding and the general radial bearing assembly are sequentially sleeved, step positioning (namely a first positioning ring platform) exists on the inner side of the front axial iron core, the bosses of the positioning ring 300 are tightly attached to realize fixed installation, step positioning exists on the inner side of the magnetic conductive ring 203, the general radial bearing assembly is tightly attached to the steps, fixed installation is realized through locking screws, a three-degree-of-freedom front bearing assembly is formed, the three-degree-of-freedom front bearing assembly, the rotor assembly 500500 and the rear axial iron core (a second iron core shell 1012) are sequentially assembled in the compressor, the three-degree-of-freedom magnetic suspension bearing is formed, and three-degree-of-freedom suspension control over the rotating shaft is realized.

The permanent magnet (i.e. the aforementioned magnetic steel 401) generates an axial-radial bias magnetic field, bias magnetic field strengths are respectively formed in a radial air gap and an axial air gap, when the thrust disk 600 is located at the center, the magnetic field strengths in the radial direction and the axial air gap of the magnetic suspension bearing are the same, the thrust disk is stably suspended, when the thrust disk is radially offset from the center, the magnetic field strengths in the radial direction and the radial air gap of the magnetic suspension bearing are different, the thrust disk continuously and radially offsets until instability occurs, a radial control magnetic field is generated through a radial control winding to adjust the magnetic field strength of the radial air gap, so that the thrust disk reversely offsets until the center to realize radial stable suspension, the axial control logic is the same, and stable suspension of the three-degree-of-freedom bearing is realized.

According to an embodiment of the invention, there is also provided a compressor including the magnetic bearing described above.

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 limited to the above preferred embodiments, and any modifications, equivalent substitutions and improvements made within the spirit and principle of the present invention should be included in the protection scope of the present invention. The above is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, several improvements and modifications can be made without departing from the technical principle of the present invention, and these improvements and modifications should also be regarded as the protection scope of the present invention.

Claims

1. The magnetic suspension bearing is characterized by comprising an axial control assembly (100) and a radial control assembly (200), wherein the axial control assembly (100) comprises an axial iron core (101) and an axial winding assembly (102) located in the axial iron core (101), and the axial winding assembly (102) is sleeved on the outer circumferential side of the radial control assembly (200).

2. The magnetic suspension bearing according to claim 1, further comprising a positioning ring (300), wherein the axial core (101) comprises a first core housing (1011) and a second core housing (1012) assembled oppositely, the inner side of the first core housing (1011) has a first positioning ring stage, the positioning ring (300) is connected to one axial side of the first positioning ring stage in a matching manner, the axial winding assembly (102) is connected to the side of the positioning ring (300) far away from the first positioning ring stage, and the first core housing (1011) and the second core housing (1012) form an axial clamping to the axial winding assembly (102) and the positioning ring (300).

3. Magnetic bearing according to claim 2, wherein the axial winding assembly (102) comprises a frame support ring (1021) and axial control windings (1022) wound in ring grooves of the frame support ring (1021), the axial winding assembly (102) being detachably connected to the positioning ring (300) via the frame support ring (1021).

4. Magnetic bearing according to claim 3, characterized in that the positioning ring (300) has an outlet hole communicating axially along it, through which outlet hole the outlet wires of the axial control winding (1022) run.

5. The magnetic suspension bearing according to claim 4, wherein a lead frame (301) is inserted into the lead hole, and the lead wire of the axial control winding (1022) passes through a central through hole of the lead frame (301).

6. The magnetic suspension bearing according to claim 2, wherein the radial control assembly (200) comprises a magnetic conductive ring (203), a radial iron core (201), and a radial control winding (202) wound around the stator teeth of the radial iron core (201), the magnetic conductive ring (203) is sleeved on the outer circumferential wall of the radial iron core (201), a second positioning ring table is provided on the central hole wall of the positioning ring (300), and the magnetic conductive ring (203) is connected to one axial side of the second positioning ring table in a matching manner.

7. The magnetic suspension bearing according to claim 6, further comprising two sets of magnetic steel assemblies (400), wherein the two sets of magnetic steel assemblies (400) are respectively connected to two axial end faces of the magnetic conductive ring (203).

8. The magnetic suspension bearing according to claim 7, wherein the magnetic steel assembly (400) comprises a plurality of magnetic steels (401) and a magnetic steel positioning ring (402), the magnetic steel positioning ring (402) has a plurality of positioning grooves arranged at intervals along a circumferential direction thereof, and the plurality of magnetic steels (401) are respectively located in the plurality of positioning grooves in a one-to-one correspondence manner.

9. The magnetic suspension bearing according to claim 8, characterized in that the magnetic steel (401) is adhered to the axial end face of the magnetic conductive ring (203); and/or the magnetic steel positioning ring (402) is detachably connected with the axial end face of the magnetic conductive ring (203).

10. The magnetic suspension bearing according to claim 1, further comprising a rotor assembly (500), wherein the rotor assembly (500) comprises a non-magnetic-conductive collar (501) and a rotor core (502) sleeved on the outer circumference side of the non-magnetic-conductive collar, the rotor core (502) is provided with core shaft end baffles (503) at two axial ends for positioning the rotor core (502) in the axial direction, the core shaft end baffles (503) are magnetic-conductive, and an axial adjusting gap is formed between the core shaft section baffles (503) and the first core shell (1011) or the second core shell (1012) adjacent to the core shaft section baffles; or, the rotor assembly (500) comprises a magnetic conduction sleeve ring (505) and a rotor core (502) sleeved on the outer circumference side of the magnetic conduction sleeve ring, iron core shaft end baffles (503) are arranged at two axial ends of the rotor core (502) to axially position the rotor core (502), the iron core shaft end baffles (503) conduct magnetism, and an axial adjustment gap is formed between the iron core shaft end baffles (503) and the first iron core shell (1011) or the second iron core shell (1012) adjacent to the iron core shaft end baffles.

11. Magnetic bearing according to claim 10, wherein when the rotor assembly (500) comprises a magnetically conductive collar (505), a magnetic shield (504) is further provided between the core shaft end shield (503) and the corresponding end of the rotor core (502).

12. The magnetic suspension bearing according to claim 1, further comprising a rotor assembly (500), wherein the rotor assembly (500) comprises a rotor core (502), the rotor core (502) is sleeved on the outer circumferential side of the thrust plate (600), the rotor core (502) is provided with core shaft end baffles (503) at two axial ends thereof to axially position the rotor core (502), and the core shaft end baffles (503) are magnetically conductive.

13. The magnetic suspension bearing according to claim 12, wherein at least one of the two core shaft end baffles (503) has an extension collar extending axially along the rotor core (502) toward one side thereof, the extension collar being fitted between the central through hole of the rotor core (502) and the outer circumferential wall of the thrust disk (600).

14. The magnetic suspension bearing according to claim 12, wherein the rotor assembly (500) further comprises a non-magnetically conductive collar (501) or a magnetically conductive collar (504), and the rotor core (502) and the non-magnetically conductive collar (501) or the magnetically conductive collar (504) are positioned with the thrust disk (600) by a positioning screw.

15. A compressor, characterized in that it comprises a magnetic bearing as claimed in any one of claims 1 to 14.