Motor rotor, rotating mechanism of motor, magnetic suspension system and centrifugal pump

Abstract

The invention provides a motor rotor, a rotating mechanism of a motor, a magnetic suspension system and a centrifugal pump. The magnetic suspension system comprises a motor stator; the motor rotor is located on the periphery of the motor stator in a spaced mode, the motor rotor comprises an annular permanent magnet, the annular permanent magnet is integrally formed and emits a magnetic field outwards to form p S poles and p corresponding N poles, p is an integer larger than or equal to 1, the ratio of the inner diameter to the outer diameter of the annular permanent magnet ranges from 0.8 to 0.91, and p is an integer larger than or equal to 1. The inner diameter of the annular permanent magnet ranges from 12 mm to 24 mm, and the outer diameter of the annular permanent magnet ranges from 13 mm to 27.5 mm. According to the motor rotor, the rotating mechanism of the motor, the magnetic suspension system and the centrifugal pump, the motor rotor is the integrally-formed annular permanent magnet, the assembling difficulty of the motor rotor can be simplified, the performance consistency of the motor can be improved, and therefore the performance of the magnetic suspension system and the performance of the centrifugal pump are improved.

Description

Technical Field

[0001] The present application relates to the field of medical devices, and in particular to a motor rotor, a rotating mechanism of a motor, a magnetic suspension system and a centrifugal pump. Background Art

[0002] The motor rotor is generally composed of multiple magnets spliced ​​together to reduce the intensity of the magnetic field emitted by the outer surface of the magnet and reduce the space occupied by the magnetic field loop. However, multiple magnets are difficult to assemble and the process consistency is difficult to ensure, resulting in poor motor performance consistency, a large three-phase no-load back EMF imbalance rate, and large motor torque fluctuations, resulting in differences in fluid stability and consistency. Three-phase no-load back EMF imbalance rate = (three-phase no-load back EMF maximum value - three-phase no-load back EMF minimum value) / three-phase no-load back EMF average value.

[0003] Therefore, it is necessary to provide a more effective and reliable technical solution to simplify the difficulty of motor rotor assembly and improve the consistency of motor performance. Summary of the invention

[0004] The present application provides a motor rotor, a rotating mechanism of a motor, a magnetic suspension system and a centrifugal pump, which can simplify the difficulty of assembling the motor rotor and improve the consistency of motor performance, thereby improving the performance of the magnetic suspension system and the performance of the centrifugal blood pump.

[0005] One aspect of the present application provides a motor rotor, which includes an annular permanent magnet that is integrally formed and emits a magnetic field outward to form p S poles and p corresponding N poles, wherein p is an integer greater than or equal to 1.

[0006] In some embodiments of the present application, the ratio of the inner diameter to the outer diameter of the annular permanent magnet is 0.8 to 0.91.

[0007] In some embodiments of the present application, the inner diameter of the annular permanent magnet is 12 to 24 mm, and / or the outer diameter of the annular permanent magnet is 13 to 27.5 mm.

[0008] In some embodiments of the present application, the thickness of the annular permanent magnet is 0.5 to 7.75 mm.

[0009] In some embodiments of the present application, p is 4, the ratio of the inner diameter to the outer diameter of the annular permanent magnet is 0.802 to 0.845, the inner diameter of the annular permanent magnet is 18.6 mm, and the outer diameter of the annular permanent magnet is 22 to 23.2 mm; or, p is 5, the ratio of the inner diameter to the outer diameter of the annular permanent magnet is 0.835 to 0.881, the inner diameter of the annular permanent magnet is 20.8 mm, and the outer diameter of the annular permanent magnet is 23.6 to 24.9 mm; or, p is 7, the ratio of the inner diameter to the outer diameter of the annular permanent magnet is 0.854 to 0.902, the inner diameter of the annular permanent magnet is 22.2 mm, and the outer diameter of the annular permanent magnet is 24.6 to 26 mm.

[0010] In some embodiments of the present application, the annular permanent magnet includes a plurality of NdFeB crystal particles, the NdFeB crystal particles located at the S pole or N pole are arranged along the radial direction of the annular permanent magnet, and the NdFeB crystal particles located between the N pole and the S pole are arranged along the tangential direction of the annular permanent magnet.

[0011] In some embodiments of the present application, the size of the NdFeB crystal particles is 2 to 80 microns.

[0012] In some embodiments of the present application, the motor rotor further includes a permanent magnet circuit, which is adjacent to the outer ring of the annular permanent magnet.

[0013] In some embodiments of the present application, the annular permanent magnet emits a magnetic field from an inner circle to an outer circle, and the outer side of the annular permanent magnet is shielded from the magnetic field by the permanent magnet loop.

[0014] In some embodiments of the present application, p is a positive integer less than or equal to 7.

[0015] One aspect of the present application further provides a rotating mechanism of a motor, comprising a motor stator and the motor rotor as described above, wherein the motor rotor is located at intervals on the outer periphery of the motor stator.

[0016] Another aspect of the present application provides a magnetic levitation system, including the rotating mechanism as described above, and: a magnetic levitation rotor circumferentially surrounding the motor rotor; and a plurality of magnetic levitation stators circumferentially uniformly surrounding the magnetic levitation rotor, the magnetic levitation stator including a magnetic levitation stator core and a magnetic levitation stator coil wound on the magnetic levitation stator core.

[0017] Another aspect of the present application also provides a centrifugal pump, comprising: a pump casing; an impeller, wherein the impeller is arranged inside the pump casing; and a magnetic levitation system as described above, which is arranged inside the pump casing, and the impeller is installed on the magnetic levitation system.

[0018] The present application provides a motor rotor, a rotating mechanism of a motor, a magnetic levitation system and a centrifugal pump, wherein the motor rotor is an integrally formed annular permanent magnet, which can simplify the difficulty of assembling the motor rotor and improve the consistency of motor performance, thereby improving the performance of the magnetic levitation system and the centrifugal pump. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The following figures describe in detail the exemplary embodiments disclosed in this application. The same reference numerals represent similar structures in several views of the drawings. Those skilled in the art will understand that these embodiments are non-limiting, exemplary embodiments, and the drawings are only for the purpose of illustration and description, and are not intended to limit the scope of this application. Other embodiments may also accomplish the inventive intent in this application. It should be understood that the drawings are not drawn to scale.

[0020] in:

[0021] Figure 1 This is a schematic diagram of the structure of the magnetic suspension system described in an embodiment of the present application;

[0022] Figure 2 This is a schematic structural diagram of an annular permanent magnet in a magnetic suspension system according to an embodiment of the present application;

[0023] Figure 3 A schematic diagram of the longitudinal cross-sectional structure of a magnetic levitation rotor and a magnetic levitation stator in a magnetic levitation system according to an embodiment of the present application;

[0024] Figure 4 The inner cylindrical surface magnetic curve of the magnetic ring of the technical solution of this application and the inner cylindrical surface magnetic curve of the 24 Halback arrays of the conventional technical solution;

[0025] Figure 5 The no-load back-EMF waveforms of a motor using the magnetic ring of the technical solution of the present application and a motor using 24 Halback arrays of the conventional technical solution;

[0026] Figure 6 This is a schematic diagram of the structure of the centrifugal pump described in the embodiment of the present application. DETAILED DESCRIPTION

[0027] The following description provides specific application scenarios and requirements of the present application, with the purpose of enabling those skilled in the art to make and use the content in the present application. It will be apparent to those skilled in the art that various local modifications to the disclosed embodiments are apparent, and the general principles defined herein may be applied to other embodiments and applications without departing from the spirit and scope of the present application. Therefore, the present application is not limited to the embodiments shown, but to the widest scope consistent with the claims.

[0028] The technical solution of the present invention is described in detail below in conjunction with the embodiments and drawings.

[0029] Figure 1 The structure diagram of the magnetic suspension system described in the embodiment of the present application is shown in FIG. The magnetic suspension system described in the embodiment of the present application is described in detail below in conjunction with the accompanying drawings.

[0030] The embodiment of the present application provides a magnetic suspension system 100, referring to Figure 1 As shown, it includes: a motor stator 110; a motor rotor 120, which circumferentially surrounds the motor stator 110, and the motor rotor 120 includes an annular permanent magnet 121, which is integrally formed and emits a magnetic field outward to form p S poles and p corresponding N poles, wherein p is an integer greater than or equal to 1.

[0031] In some embodiments of the present application, the ratio of the inner diameter to the outer diameter of the annular permanent magnet 121 is 0.8 to 0.91; the inner diameter of the annular permanent magnet 121 is 12 to 24 mm; and / or the outer diameter of the annular permanent magnet 121 is 13 to 27.5 mm.

[0032] In some embodiments of the present application, the motor stator 110 includes a gear-shaped motor stator core and a plurality of coils wound on the teeth of the motor stator core, wherein the plurality of coils are grouped into multi-phase (e.g., 3-phase) windings. The motor rotor 120 is located at intervals on the outer periphery of the motor stator 110. The motor rotor 120 and the motor stator 110 constitute a rotating mechanism of the motor.

[0033] In some embodiments of the present application, the material of the annular permanent magnet 121 is sintered NdFeB. The magnetic poles of the annular permanent magnet 121 are formed by the internal magnetic domain distribution, and the magnetic domain is composed of smaller magnetic crystal particles (i.e., NdFeB crystal particles). The magnetic poles can be formed by arranging the magnetic crystal particles in a specific direction.

[0034] In some embodiments of the present application, the annular permanent magnet 121 includes a plurality of NdFeB crystal particles. By setting the arrangement direction of the NdFeB crystal particles, magnetic poles can be formed on the annular permanent magnet 121. Specifically, for example, the NdFeB crystal particles located at the S pole or N pole are arranged along the radial direction of the annular permanent magnet, and the NdFeB crystal particles located between the N pole and the S pole are arranged along the tangential direction of the annular permanent magnet.

[0035] In some embodiments of the present application, the size of the NdFeB crystal particles is 2 to 80 microns, for example, 50 to 60 microns. The size of the NdFeB crystal particles refers to the diameter of the NdFeB crystal particles when they are approximated as a sphere or the side length when they are approximated as a square. The shape of the NdFeB crystal particles is generally irregular, but can be approximated as a sphere or a square. Under this structure and size, the NdFeB crystal particles are uniform, have good mechanical properties, and are easier to form.

[0036] In some embodiments of the present application, the annular permanent magnet 121 is configured to include p S poles and p corresponding N poles, where p is an integer greater than or equal to 1. For example, p may be 1, 2, 3, 4, 5, 6 or 7. In the application of a centrifugal blood pump, the inventor of the present application has found that using a positive integer less than 7 for p is beneficial to improving the efficiency of the entire blood pump.

[0037] Figure 2 This is a schematic diagram of the structure of the annular permanent magnet in the magnetic levitation system described in an embodiment of the present application.

[0038] refer to Figure 2 As shown, Figure 2 The annular permanent magnet 121 shown is exemplified by p=5. That is, the annular permanent magnet 121 includes 5 S poles (respectively S1, S2, S3, S4, S5) and 5 N poles (respectively N1, N2, N3, N4, N5). The S poles and N poles correspond to each other one by one, that is, the magnetic field emitted outward by S1 is received by N1, the magnetic field emitted outward by S2 is received by N2, the magnetic field emitted outward by S3 is received by N3, the magnetic field emitted outward by S4 is received by N4, and the magnetic field emitted outward by S5 is received by N5.

[0039] Continue to refer Figure 2 As shown, the inner diameter of the annular permanent magnet 121 is marked as Dr i, the outer diameter of the annular permanent magnet 121 is marked as Dro, and the thickness of the annular permanent magnet 121 is marked as Hm. The following describes the implementation scheme of the annular permanent magnet with p=4, p=5, and p=7 respectively.

[0040] In some embodiments of the present application, p is 4, and the ratio of the inner diameter to the outer diameter of the annular permanent magnet 121 is 0.802 to 0.845. For example, the inner diameter of the annular permanent magnet 121 is 18.6 mm, and the outer diameter of the annular permanent magnet 121 is 22 to 23.2 mm; the radial thickness of the annular permanent magnet 121 (the difference between the outer diameter and the inner diameter divided by 2) is 1.7 to 2.3 mm.

[0041] In some embodiments of the present application, p is 5, and the ratio of the inner diameter to the outer diameter of the annular permanent magnet 121 is 0.835 to 0.881. For example, the inner diameter of the annular permanent magnet 121 is 20.8 mm, and the outer diameter of the annular permanent magnet 121 is 23.6 to 24.9 mm; the radial thickness of the annular permanent magnet 121 is 1.4 to 2.05 mm.

[0042] In some embodiments of the present application, p is 7, and the ratio of the inner diameter to the outer diameter of the annular permanent magnet 121 is 0.854 to 0.902. For example, the inner diameter of the annular permanent magnet 121 is 22.2 mm, the outer diameter of the annular permanent magnet 121 is 24.6 to 26 mm, and the radial thickness of the annular permanent magnet 121 is 1.2 to 1.9 mm.

[0043] The inventor of the present application adopts a creative thinking different from the conventional conception, and uses the number of magnetic poles of the annular permanent magnet 121 and the corresponding size setting, which can not only improve the magnetic field emission effect of the annular permanent magnet 121, but also does not need to form an annular permanent magnet by splicing multiple magnetic steels as in the conventional design idea, but uses a complete annular permanent magnet, which has a simple structure, greatly reduces the difficulty of assembly, and can improve the consistency of motor performance during use. In particular, the number of magnetic poles of the annular permanent magnet 121 corresponding to the present application and the amplitude and pole width of the emitted magnetic field are uniform, that is, the intensity amplitude of the emitted magnetic field and the angle occupied by each pole in the circumferential direction of the magnetic field are uniform, and the amplitude is higher than that of the magnetic ring assembled by multiple magnetic steels in the conventional technology, and the utilization rate of the magnetic field is improved.

[0044] Continue to refer Figure 1 As shown, in some embodiments of the present application, the annular permanent magnet 121 emits a magnetic field from the inner ring to the outside. The annular permanent magnet 121 includes two upper and lower end faces and two inner and outer cylindrical surfaces. The inner ring refers to the cylindrical surface inside the annular permanent magnet 121.

[0045] Continue to refer Figure 1 As shown, in some embodiments of the present application, the motor rotor 120 further includes a permanent magnet loop 122, which is located on the outer ring of the annular permanent magnet 121. The inner side of the annular permanent magnet 121 is used to emit a magnetic field, while the outer side of the annular permanent magnet 121 is shielded from the magnetic field by the permanent magnet loop 122. The outer ring of the magnetic ring does not need to provide a permanent magnet loop, saving radial space, and only requires the target magnetic field to be emitted along the inner ring and its magnetic field loop to be closed along the inside of the permanent magnet.

[0046] Figure 3 This is a schematic diagram of the longitudinal cross-sectional structure of the magnetic levitation rotor and the magnetic levitation stator in the magnetic levitation system described in an embodiment of the present application.

[0047] refer to Figure 1 and Figure 3 As shown, in some embodiments of the present application, the magnetic levitation system 100 further includes: a magnetic levitation rotor 130, which circumferentially surrounds the motor rotor 120; and a plurality of magnetic levitation stators 140, which circumferentially uniformly surround the magnetic levitation rotor 130, wherein the magnetic levitation stator 140 includes a magnetic levitation stator core 141 and a magnetic levitation stator coil 142 wound on the magnetic levitation stator core 141. The magnetic levitation rotor 130 and the magnetic levitation stator 140 constitute a magnetic levitation assembly.

[0048] In some embodiments of the present application, the material of the magnetically floating rotor 130 is a permanent magnet. The magnetically floating rotor 130 is magnetized along the axial direction.

[0049] In some embodiments of the present application, the number of the plurality of magnetic levitation stators 140 is at least two pairs, that is, an even number greater than or equal to four.

[0050] In some embodiments of the present application, the plurality of magnetic levitation stators 140 are not magnetically connected to each other, that is, each magnetic levitation stator 140 is independent in the magnetic circuit.

[0051] In some embodiments of the present application, the magnetic levitation stator core 141 is provided with a mounting groove, and the magnetic levitation stator coil 142 is wound in the mounting groove. Figure 3 As shown, the magnetic levitation stator core 141 is in a “concave” shape, and the concave portion of the “concave” character faces the magnetic levitation rotor 130 , wherein the mounting groove is the concave portion of the “concave” character.

[0052] In some other embodiments of the present application, the magnetic levitation stator core 141 may also be in the shape of an “I”, and the depressions on both sides of the “I” serve as installation grooves.

[0053] In some embodiments of the present application, the magnetic levitation component also includes: an active control system (not shown in the figure), configured to provide active stability regarding the radial displacement of the magnetic levitation rotor 130, and the active control system includes: a displacement sensor, used to detect the radial offset of the magnetic levitation rotor 130; a controller, receiving the detection result of the displacement sensor, configured to output a control current to the magnetic levitation stator coil 142 when the radial offset detected by the displacement sensor is greater than an offset threshold value so that the radial offset of the magnetic levitation rotor 130 returns to within the offset threshold value.

[0054] The applicant also conducted comparative tests on the motor rotors of the technical solution of the present application and the conventional technical solution, and recorded the test results to compare the technical effects. Among them, the embodiment is the annular permanent magnet (marked as a magnetic ring) provided by the technical solution of the present application, and the comparative example is the magnetic steel (marked as 24 Halback arrays) arranged in the conventional technical solution.

[0055] Test 1 is to measure the inner cylindrical surface magnetic curves of the embodiment and the comparative example, as shown in FIG. Figure 4 shown.

[0056] Figure 4 This is a comparison chart of the inner cylindrical surface magnetic curve of the magnetic ring of the technical solution of this application and the inner cylindrical surface magnetic curve of the 24 Halback arrays of the conventional technical solution.

[0057] refer to Figure 4 As shown, compared with the 24 Halback array-arranged magnets in the conventional technical solution, the annular permanent magnets of the technical solution of the present application have uniform surface magnetism, and have better consistency in amplitude and pole width.

[0058] Test 2 is to measure the no-load back EMF waveform of the motor composed of the embodiment and the comparative example, as shown in the following figure: Figure 5 shown.

[0059] Figure 5 The no-load back EMF waveforms of the motor using the magnetic ring of the technical solution of this application and the motor using the conventional technical solution of 24 Halback arrays. The no-load back EMF in this application refers to a potential output by the motor when the rotor speed reaches the synchronous speed but the motor is not loaded during the operation of the motor.

[0060] refer to Figure 5 As shown, compared with the motor using 24 Halback array-arranged magnetic steels in the conventional technical solution, the motor using the annular permanent magnet of the technical solution of the present application has a large no-load back EMF amplitude and good consistency, stable motor performance and greater output, better efficiency, and small output torque fluctuation.

[0061] The motor rotor of the technical solution of the present application is an integrally formed annular permanent magnet, which is easy to assemble, has good consistency in motor manufacturing process, and has good consistency in motor performance.

[0062] The integrally formed annular permanent magnet in the technical solution of the present application may include a plurality of N poles and S poles, and only the inner cylindrical surface emits a magnetic field uniformly, while the outer cylindrical surface and the two end surfaces do not emit a magnetic field outward.

[0063] The technical solution of the present application can select a suitable size of annular permanent magnet according to the size of the motor, and can select a suitable number of magnetic pole pairs according to the application.

[0064] The technical solution of the present application has a large no-load back electromotive force of the motor within a limited space, improves the utilization rate of the magnetic field, improves the actual working efficiency of the motor part, reduces battery power consumption, and has good stability.

[0065] The present application provides a magnetic levitation system, wherein the motor rotor is an integrally formed annular permanent magnet, which can simplify the difficulty of assembling the motor rotor, improve the consistency of motor performance, and thus improve the performance of the magnetic levitation system.

[0066] Figure 6 This is a schematic diagram of the structure of the centrifugal pump described in the embodiment of the present application.

[0067] The embodiment of the present application also provides a centrifugal pump, referring to Figure 6 As shown, it includes: a pump head 210; a pump machine 220, the pump machine 220 carries the pump head 210; the magnetic suspension system 100 (attached Figure 6 ), wherein the motor stator 110 and the motor rotor 120 in the magnetic levitation system 100 are arranged in the pump 220, and the magnetic levitation stator 140 and the magnetic levitation rotor 130 in the magnetic levitation system 100 are arranged in the pump head.

[0068] The present application provides a magnetic levitation system and a centrifugal pump, such as a centrifugal blood pump, whose motor rotor is an integrally formed annular permanent magnet, which can simplify the difficulty of motor rotor assembly and improve the consistency of motor performance, thereby improving the performance of the magnetic levitation system and the centrifugal blood pump.

[0069] In summary, after reading the contents of this application, those skilled in the art will appreciate that the aforementioned application contents may be presented only in an exemplary manner and may not be restrictive. Although not explicitly stated herein, those skilled in the art will appreciate that this application is intended to encompass various reasonable changes, improvements and modifications to the embodiments. These changes, improvements and modifications are within the spirit and scope of the exemplary embodiments of this application.

[0070] It should be understood that the term "and / or" used in this embodiment includes any or all combinations of one or more of the associated listed items. It should be understood that when an element is referred to as being "connected" or "coupled" to another element, it can be directly connected or coupled to another element, or there can also be intermediate elements.

[0071] The term "permanent magnet" or "magnet" used in this embodiment refers to a component made of a ferromagnetic material with large remanence and large coercivity and magnetized to serve as a source of a magnetic field, such as NeFeB, as known to those skilled in the art. "Soft iron" used herein refers to a component made of a laminated or non-laminated ferromagnetic material with small remanence and small coercivity and used to guide magnetic flux, such as pure iron, silicon steel or Hiperco alloy, as known to those skilled in the art.

[0072] It should also be understood that the terms "comprising", "containing", "including" or "comprising", when used in this application document, indicate the presence of the recorded features, wholes, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components and / or groups thereof.

[0073] It should also be understood that although the terms first, second, third, etc. can be used to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another element. Therefore, without departing from the teachings of the present application, the first element in some embodiments can be referred to as the second element in other embodiments. The same reference numerals or the same reference signs represent the same elements throughout the specification.

[0074] In addition, the present specification describes exemplary embodiments by reference to idealized exemplary cross-sectional views and / or plan views and / or stereograms. Therefore, differences from the illustrated shapes due to, for example, manufacturing techniques and / or tolerances are foreseeable. Therefore, the exemplary embodiments should not be interpreted as being limited to the shapes of the regions shown herein, but should include deviations in shapes caused by, for example, manufacturing. Therefore, the regions shown in the figures are schematic in nature, and their shapes are not intended to illustrate the actual shapes of the regions of the device nor to limit the scope of the exemplary embodiments.

Claims

1. A motor rotor, characterized in that: The motor rotor comprises an annular permanent magnet, which is integrally formed and emits a magnetic field outward to form p S poles and p corresponding N poles, wherein p is an integer greater than or equal to 1.

2. The motor rotor according to claim 1, characterized in that: The ratio of the inner diameter to the outer diameter of the annular permanent magnet is 0.8 to 0.

91.

3. The motor rotor according to claim 1, characterized in that: The inner diameter of the annular permanent magnet is 12 to 24 mm, and / or the outer diameter of the annular permanent magnet is 13 to 27.5 mm.

4. The motor rotor according to claim 1, characterized in that: The thickness of the annular permanent magnet is 0.5 to 7.75 mm.

5. The motor rotor according to claim 1, characterized in that: p is 4, the ratio of the inner diameter to the outer diameter of the annular permanent magnet is 0.802 to 0.845, the inner diameter of the annular permanent magnet is 18.6 mm, and the outer diameter of the annular permanent magnet is 22 to 23.2 mm; or, p is 5, the ratio of the inner diameter to the outer diameter of the annular permanent magnet is 0.835 to 0.881, the inner diameter of the annular permanent magnet is 20.8 mm, and the outer diameter of the annular permanent magnet is 23.6 to 24.9 mm; or, p is 7, the ratio of the inner diameter to the outer diameter of the annular permanent magnet is 0.854 to 0.902, the inner diameter of the annular permanent magnet is 22.2 mm, and the outer diameter of the annular permanent magnet is 24.6 to 26 mm.

6. The motor rotor according to claim 1, characterized in that: The annular permanent magnet includes a plurality of NdFeB crystal particles. The NdFeB crystal particles located at the S pole or N pole are arranged along the radial direction of the annular permanent magnet, and the NdFeB crystal particles located between the N pole and the S pole are arranged along the tangential direction of the annular permanent magnet.

7. The motor rotor according to claim 6, characterized in that: The size of the NdFeB crystal particles is 2 to 80 microns.

8. The motor rotor according to claim 1, characterized in that: The motor rotor also includes a permanent magnet loop, which is adjacent to the outer ring of the annular permanent magnet.

9. The motor rotor according to claim 8, characterized in that: The annular permanent magnet emits a magnetic field outward from the inner circle, and the outer side of the annular permanent magnet is shielded from the magnetic field by the permanent magnet loop.

10. The motor rotor according to claim 1, characterized in that: The p is a positive integer less than or equal to 7.

11. A rotating mechanism of a motor, characterized in that: It comprises a motor stator and a motor rotor as claimed in any one of claims 1 to 10, wherein the motor rotor is located at intervals on the outer periphery of the motor stator.

12. A magnetic levitation system, characterized in that: The invention comprises the rotating mechanism as claimed in claim 11, and: A magnetically floating rotor circumferentially surrounding the motor rotor; and A plurality of magnetic levitation stators uniformly surround the magnetic levitation rotor along the circumferential direction, wherein the magnetic levitation stators include a magnetic levitation stator core and a magnetic levitation stator coil wound on the magnetic levitation stator core.

13. A centrifugal pump, characterized in that: include: Pump housing; An impeller, wherein the impeller is disposed inside the pump casing; The magnetic levitation system as described in claim 12 is arranged inside the pump casing, and the impeller is installed on the magnetic levitation system.

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