WO2025112797A9 - Permanent magnet electric motor, electric motor rotor system, and manufacturing method therefor - Google Patents

Abstract

Provided in the embodiments of the present disclosure are a permanent magnet electric motor, an electric motor rotor system, and a manufacturing method therefor, which relate to the technical field of permanent magnet electric motors. The electric motor rotor system comprises a support device and a rotor assembly, wherein the support device has a first support rotation center and a second support rotation center that are spaced apart; and the rotor assembly is rotatably connected to the support device at the first support rotation center and the second support rotation center, respectively, and rotates around the line connecting the first support rotation center and the second support rotation center, the distance between the first support rotation center and the center of gravity of the rotor assembly is a first distance, the distance between the second support rotation center and the center of gravity of the rotor assembly is a second distance, and the first distance is equal to the second distance.

Description

Permanent magnet motor, motor rotor system and manufacturing method thereof

CROSS-REFERENCE TO RELATED APPLICATIONS

This disclosure is based on Chinese patent application with application number 202311626223.4, application date November 30, 2023, and invention name “Permanent magnet motor, motor rotor system and manufacturing method thereof”, and claims the priority of the Chinese patent application. The entire content of the Chinese patent application is hereby introduced into this disclosure as a reference.

Technical Field

The present disclosure relates to the field of permanent magnet motors, and in particular to permanent magnet motors, motor rotor systems, and manufacturing methods thereof.

Background Art

With the continuous development of the motor industry, the motor speed is also increasing. High-speed permanent magnet motors are increasingly used in air compressors, energy storage flywheels, high-speed pumps and other fields. High-speed permanent magnet motors have many advantages, such as small size and high power density. Because the motor speed is very high, the linear speed of the rotor surface can reach 200m/s when the motor rotates. However, the rotor structure of traditional permanent magnet motors is difficult to meet the requirements of high-speed motors. There are often different bearing capacities provided by the support devices on both sides, and the bearing capacity on one side is too large, which can easily reduce the reliability of the permanent magnet motor when running at high speed.

Summary of the invention

In view of this, the embodiments of the present disclosure hope to provide a permanent magnet motor, a motor rotor system and a manufacturing method thereof, which are conducive to making the bearing capacity provided by the supporting devices on both sides as consistent as possible when the permanent magnet motor runs at high speed.

To achieve the above objectives, the technical solution of the embodiment of the present disclosure is implemented as follows:

The present disclosure provides a motor rotor system, comprising:

A support device having a first support rotation center and a second support rotation center arranged at intervals;

The rotor assembly is rotatably connected to the support device at the first support rotation center and the second support rotation center, respectively. The rotor assembly rotates around a line connecting the first support rotation center and the second support rotation center. The distance between the first support rotation center and the center of gravity of the rotor assembly is a first distance. The distance between the second support rotation center and the center of gravity of the rotor assembly is a second distance. The first distance is equal to the second distance.

In one embodiment, a midpoint of a line connecting the first support rotation center and the second support rotation center coincides with the center of gravity of the rotor assembly.

In one embodiment, the support device includes two support members arranged at an interval, the first support rotation center is formed on one of the support members, and the second support rotation center is formed on the other of the support members.

In one embodiment, the rotor assembly comprises:

A working component having a receiving cavity;

A permanent magnet component is installed in the accommodating cavity, and the permanent magnet component is a solid structure.

In one embodiment, the permanent magnet assembly includes a plurality of stacked permanent magnets and an insulating layer disposed between two adjacent permanent magnets, and the permanent magnets are configured in a disc shape.

In one embodiment, the working component includes:

jacket;

A shaft assembly, wherein the shaft assembly is respectively arranged at two axial ends of the sleeve, and the sleeve and the shaft assembly surround the accommodating cavity.

In one embodiment, the sleeve is welded to the shaft assembly.

In one embodiment, the permanent magnet component is located in the sheath, and the sheath and the permanent magnet component are interference fit.

In one embodiment, the shaft assembly has a weight-reducing hole, and the weight-reducing hole is formed at one end of the shaft assembly close to the permanent magnet assembly.

In one embodiment, the shaft assembly comprises:

A shaft body, wherein the weight-reducing hole is formed in the shaft body;

A sealing cover is arranged between the shaft body and the permanent magnet assembly to close the weight-reducing hole.

In one embodiment, the shaft assembly further has an exhaust hole connected to the outside world, so as to connect the weight-reducing hole to the outside world.

In one embodiment, there are at least two exhaust holes, and the exhaust holes are arranged in pairs along the radial direction of the shaft assembly.

In one embodiment, the exhaust hole is arranged to be inclined along the radial direction of the shaft assembly, and the inclination direction of the exhaust hole is the same as the rotation direction of the shaft assembly.

In one embodiment, the working component further includes a locking member and a displacement sensor mounted on the locking member, wherein the locking member is disposed at an end of the shaft assembly away from the permanent magnet assembly, and the displacement sensor is used to monitor the axial and radial motion trajectory of the motor rotor system.

The present disclosure also provides a permanent magnet motor, comprising:

The motor rotor system according to any one of the preceding embodiments;

Stator core.

In one embodiment, the axial length of the permanent magnet assembly is greater than the axial length of the stator core.

The present disclosure also provides a method for manufacturing a motor rotor system, wherein the rotor assembly includes a working component and a permanent magnet component, wherein the working component includes a sleeve and a shaft component, and the manufacturing method includes:

Taking the outer peripheral surface of the permanent magnet assembly as a radial positioning reference, the sheath is sleeved on the permanent magnet assembly;

The position of the shaft assembly relative to the sleeve along the axial direction of the sleeve is determined by taking the sleeve as an axial positioning reference.

In one embodiment, the permanent magnet assembly specifically includes:

A plurality of disc-shaped permanent magnets are bonded together to form the cylindrical permanent magnet assembly.

Effects of the Invention

In the motor rotor system provided by the embodiment of the present disclosure, the distance from the center of gravity of the rotor assembly to the first support rotation center is equal to the distance from the rotor assembly to the second support rotation center, so that the bearing capacity of the first support rotation center and the second support rotation center are as consistent as possible, which is beneficial to reducing the risk of unstable operation caused by unbalanced bearing capacity of the bearings at both ends when the rotor assembly rotates at high speed, and improving the reliability of high-speed rotation of the rotor assembly.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a schematic diagram of a permanent magnet motor in an embodiment of the present disclosure;

FIG2 is a schematic diagram of a shaft body in an embodiment of the present disclosure;

FIG3 is a radial cross-sectional view of the shaft body at the exhaust hole A-A in FIG2 ;

FIG4 is a schematic diagram of a locking member in an embodiment of the present disclosure;

FIG. 5 is a schematic flow chart of a method for manufacturing a motor rotor system according to an embodiment of the present disclosure.

Description of Reference Numerals
1. Rotor assembly; 1a. Center of gravity; 1b. First support rotation center; 1c. Second support rotation center; 10. Working part; 11. Permanent magnet assembly; 111. Permanent magnet; 12. Shaft assembly; 121. Shaft body; 1211. External hexagonal square head; 122. Cover; 121a. Lightening hole; 121b. Exhaust hole; 13. Sleeve; 15. Locking piece; 161. Low-pressure side impeller; 162. High-pressure side impeller; 17. Thrust plate; 2. Support device; 21. Support member; 3. Stator core.

DETAILED DESCRIPTION

The following is a further detailed description of the embodiments of the present disclosure in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present disclosure but are not intended to limit the scope of the present disclosure.

In the description of the embodiments of the present disclosure, it should be noted that the terms "circumferential", "axial", "radial", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the embodiments of the present disclosure and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the embodiments of the present disclosure. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

In the description of this specification, the description with reference to the term "some embodiments" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment are included in at least one embodiment of the disclosed embodiments. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment. Moreover, the specific features, structures, materials or characteristics described may be combined in a suitable manner in any one or more embodiments. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

In the related art, the rotor structure using independent long screw positioning or threaded assembly makes the position deviation of the components on both sides particularly obvious. When running at high speed, it is easy to cause local damage and heating of the bearings due to uneven force on the bearings on both sides, and the rotor generates additional axial force, and the operation stability is poor.

In view of this, please refer to FIG. 1 , an embodiment of the present disclosure provides a motor rotor system, which includes a supporting device 2 and a rotor assembly 1 .

The support device 2 has a first support rotation center 1b and a second support rotation center 1c arranged at intervals. The rotor assembly 1 is rotationally connected to the support device 2 at the first support rotation center 1b and the second support rotation center 1c, respectively, and the rotor assembly 1 rotates around the line connecting the first support rotation center 1b and the second support rotation center 1c.

Among them, the distance between the first support rotation center 1b and the center of gravity 1a of the rotor assembly 1 is the first distance, the distance between the second support rotation center 1c and the center of gravity 1a of the rotor assembly 1 is the second distance, and the first distance is equal to the second distance.

In the disclosed embodiment, since the first distance and the second distance are equal, the bearing capacities of the first support rotation center 1b and the second support rotation center 1c on the rotor assembly 1 are substantially equal in magnitude and roughly the same in direction, and the force on the rotor assembly 1 is relatively uniform, which is beneficial to improving the stability of the rotor assembly 1 during high-speed rotation and reducing local damage and heat generation of the bearing.

In one embodiment, referring to FIG. 1 , the midpoint of a line connecting the first support rotation center 1 b and the second support rotation center 1 c coincides with the center of gravity 1 a of the rotor assembly 1 .

In the disclosed embodiment, while the first distance and the second distance are equal, the center of gravity 1a of the rotor assembly 1 is on the line connecting the first support rotation center 1b and the second support rotation center 1c, so that the centrifugal force on the rotor assembly 1 during rotation is smaller, which is beneficial to improving the stability and reliability of the rotor assembly 1 during high-speed rotation.

It is understandable that the position of the center of gravity 1a of the rotor assembly 1 is not limited. For example, the midpoint of the line connecting the first support rotation center 1b and the second support rotation center 1c and the center of gravity 1a of the rotor assembly 1 can be staggered.

In one embodiment, referring to FIG. 1 , the support device 2 includes two support members 21 arranged at an interval, a first support rotation center 1 b is formed on one of the support members 21 , and a second support rotation center 1 c is formed on the other support member 21 .

In the disclosed embodiment, the distance between the two support members 21 can be arranged according to actual needs. The arrangement of the two support members 21 is more flexible and more convenient for maintenance.

It is understandable that the type of the support member 21 is not limited here. For example, the support member 21 is a bearing, which is arranged at intervals on both sides of the rotor assembly 1 along the axial direction. For example, the support member 21 is a supporting whole, and the rotor assembly 1 is mounted on the supporting whole.

In one embodiment, referring to FIG1 , the rotor assembly 1 includes a working component 10 and a permanent magnet assembly 11. The working component 10 has a receiving cavity, and the permanent magnet assembly 11 is a solid structure and is installed in the receiving cavity of the working component 10.

In the disclosed embodiment, the solid structure of the permanent magnet component 11 improves the rigidity of the rotor assembly 1 and can withstand the centrifugal force caused by a higher rotation speed. Therefore, at the same rotation speed, the protective cover required for the solid structure of the permanent magnet component 11 is thinner, which reduces the difficulty of assembly. At the same time, the solid structure of the permanent magnet component 11 can avoid the generation of axial force on the rotor assembly 1 that causes axial eccentricity of the rotor assembly 1, reduces the axial bearing capacity of the bearing, reduces heat generation, and is beneficial to improving the stability of high-speed rotation of the rotor and the anti-demagnetization ability of the permanent magnet component 11. In addition, the solid structure of the permanent magnet component 11 has a higher magnetic flux density. Therefore, at the same magnetic flux density, the solid cylindrical structure of the permanent magnet component 11 can reduce the length of the rotating shaft and the stator core, thereby improving the power density of the permanent magnet motor and increasing the first-order bending critical speed of the motor rotor system.

It is understandable that the radial cross-sectional shape of the permanent magnet assembly 11 is not limited, and may be, for example, circular or rectangular. Exemplarily, the permanent magnet assembly 11 is a solid cylindrical structure.

In one embodiment, referring to FIG. 1 , the permanent magnet assembly 11 includes a plurality of stacked disc-shaped permanent magnets 111 and an insulating layer disposed between two adjacent permanent magnets 111 .

In the disclosed embodiment, the permanent magnet assembly 11 is formed by bonding multiple disc-shaped permanent magnets 111 with consistent magnetic field orientation in sections along the axial direction using insulating adhesive material. Since the permanent magnet assembly 11 is separated by insulating material inside, the eddy current loss inside the permanent magnet assembly 11 can be effectively reduced.

It is understandable that the material of the permanent magnet 111 is not limited, and it can be, for example, a neodymium iron boron permanent magnet, a samarium cobalt permanent magnet, or an aluminum nickel cobalt permanent magnet.

There is no limitation on the material of the insulating layer, as long as it meets the requirements of high strength, high insulation, and high temperature resistance.

Exemplarily, the permanent magnet 111 is made of rare earth samarium cobalt 2:17 permanent magnet material, bonded in sections along the axial direction, each permanent magnet 111 is 7 to 10 mm thick, the insulation layer thickness is less than or equal to 0.1 mm, and the insulation layer temperature resistance is not less than 220°C.

In one embodiment, referring to Fig. 1, the working component 10 includes a sheath 13 and a shaft assembly 12. The sheath 13 is provided with shaft assemblies 12 at both ends along the axial direction, and the sheath 13 and the shaft assembly 12 surround the working component 10 to form a receiving cavity for installing the permanent magnet assembly 11.

In the disclosed embodiment, the sleeve 13 is installed with the radial size of the permanent magnet assembly 11 as a positioning reference, and the shaft assembly 12 is connected with the sleeve 13 as an axial positioning reference, so that the basic structure formed by the working component 10 has a higher installation accuracy, which is beneficial to improving the reliability of the rotor assembly 1 during high-speed rotation.

In one embodiment, the sheath 13 is welded to the shaft assembly 12 .

In the disclosed embodiment, the sleeve 13 and the shaft assembly 12 can be processed independently and then welded into one, which helps to reduce the difficulty of processing the sleeve 13 and the shaft assembly 12.

Exemplarily, the sleeve 13 and the shaft assembly 12 are laser welded into one body. The sleeve 13 and the shaft assembly 12 are easy to process, easy to assemble, and both the position tolerance and the size tolerance can be guaranteed.

In one embodiment, referring to FIG. 1 , the permanent magnet component 11 is located in the sheath 13 , and the permanent magnet component 11 and the sheath 13 are interference fit.

In the disclosed embodiment, the permanent magnet assembly 11 and the sleeve 13 are interference fit, and the outer peripheral side surface of the permanent magnet assembly 11 is tightly fitted with the inner peripheral side surface of the sleeve 13, so there is no gap between the matching surfaces of the permanent magnet assembly 11 and the sleeve 13. When the rotor assembly 1 rotates at high speed, the sleeve 13 can protect the permanent magnet assembly 11 and prevent the permanent magnet assembly 11 rotating at high speed from disintegrating and failing due to centrifugal force, which is beneficial to increase the rotation speed of the rotor assembly 1. In addition, the sleeve 13 can prevent the permanent magnet assembly 11 from being eccentric in the radial and axial directions when rotating at high speed, thereby reducing the maximum centrifugal force and unbalanced magnetic pull of the permanent magnet assembly 11, and improving the operating performance and stability of the permanent magnet motor.

In one embodiment, referring to FIG. 1 , the sheath 13 is welded to the shaft assembly 12 , the permanent magnet assembly 11 is located in the sheath 13 , and the permanent magnet assembly 11 and the sheath 13 are interference fit.

In the disclosed embodiment, the permanent magnet assembly 11 and the sleeve 13 are interference fit, and the sleeve 13 and the shaft assembly 12 are welded into one body, which is beneficial to improving the rigidity of the rotor assembly 1, and is also beneficial to improving the assembly accuracy of the permanent magnet assembly 11, the sleeve 13 and the shaft assembly 12, so as to reduce the risk of instability of the permanent magnet motor during high-speed operation due to low assembly accuracy.

It is understandable that the material of the sheath 13 is not limited, and may be iron, cobalt or nickel, for example. For example, the sheath 13 is made of GH4169 high temperature nickel-based alloy, and the hardness is HRC38-45.

In one embodiment, referring to FIG. 1 and FIG. 2 , the shaft component 12 has a weight-reducing hole 121 a , and the weight-reducing hole 121 a is formed at one end of the shaft component 12 close to the permanent magnet component 11 .

In the embodiment of the present disclosure, the shaft assembly 12 with the weight-reducing hole 121a is lighter in weight, and therefore has a smaller moment of inertia, a faster dynamic response, and a lower load-bearing requirement for the support member 21, which is beneficial to improving the start-stop life of the shaft assembly 12.

In one embodiment, referring to Figures 1 and 2, the shaft assembly 12 includes a shaft body 121 and a cover 122. A weight-reducing hole 121a is formed in the shaft body 121; the cover 122 is disposed between the shaft body 121 and the permanent magnet assembly 11 to close the weight-reducing hole 121a.

In the disclosed embodiment, the shaft body 121 is formed with a weight-reducing hole 121a at one end close to the permanent magnet assembly 11, which is closed by a cover 122, and the shaft assembly 12 is connected to the permanent magnet assembly 11 through the cover 122. If the permanent magnet assembly 11 is broken during high-speed rotation, the cover 122 can seal the broken permanent magnet assembly 11 in the accommodating cavity to prevent the broken permanent magnet assembly 11 from causing secondary damage to the permanent magnet motor.

In one embodiment, referring to FIG. 1 and FIG. 2 , the shaft body 121 is bonded to the cover 122 to close the weight-reducing hole 121 a , and the shaft assembly 12 is bonded to the permanent magnet assembly 11 through the cover 122 .

In the disclosed embodiment, the cover 122 increases the bonding area between the shaft assembly 12 and the permanent magnet assembly 11, thereby improving the bonding strength. At the same time, it avoids the risk of the bonding material leaking into the weight-reducing hole 121a due to assembly extrusion, causing the rotor assembly 1 to rotate unbalanced, which is beneficial to improving the stability of the permanent magnet motor.

It is understandable that the assembly method of the shaft body 121, the cover 122 and the permanent magnet assembly 11 is not limited. Exemplarily, the cover 122 is first bonded to the permanent magnet assembly 11, and then the shaft body 121 is bonded to the cover 122 to close the weight reduction hole 121a.

The material of the shaft body 121 is not limited, and may be iron, cobalt or nickel, for example. For example, the shaft body 121 is made of GH4169 high temperature nickel-based alloy, and the hardness is HRC38-45.

The material of the cover 122 is not limited, and may be iron, cobalt or nickel, for example.

In one embodiment, referring to FIGS. 1 to 3 , the shaft assembly 12 further has an exhaust hole 121 b communicating with the outside, so as to connect the lightening hole 121 a with the outside.

In the disclosed embodiment, the exhaust hole 121b is also located on the side of the shaft body 121 close to the permanent magnet assembly 11 and is arranged radially along the shaft body 121. While further reducing the weight of the shaft body 121, when the rotor assembly 1 rotates at high speed, the gas inside the shaft body 121 that expands due to heat can be smoothly discharged to the outside.

In one embodiment, referring to FIGS. 1 to 3 , there are at least two exhaust holes 121 b , and the exhaust holes 121 b are arranged in pairs along the radial direction of the shaft assembly 12 .

In the disclosed embodiment, the number of exhaust holes 121b is even, and one of the exhaust holes 121b arranged in pair can overlap with the initial position of another exhaust hole 121b after rotating 180° circumferentially, which is beneficial for the shaft body 121 to maintain dynamic balance during high-speed rotation.

In one embodiment, referring to FIGS. 1 to 3 , the exhaust hole 121 b is tilted along the radial direction of the shaft assembly 12 , and the tilt direction of the exhaust hole 121 b is the same as the rotation direction of the shaft assembly 12 .

In the disclosed embodiment, the axial direction of the exhaust hole 121b does not coincide with the radial direction of the shaft assembly 12, but is inclined at a certain angle, and the inclination direction is the same as the rotation direction of the shaft assembly 12, so that the airflow is not easy to flow into the shaft assembly 12 when the shaft assembly 12 rotates at a high speed, thereby reducing the influence of the rotating airflow on the wind wear loss of the shaft assembly 12. As shown in FIG3, the rotation direction indicated by the reference numeral A is the rotation direction of the shaft assembly 12.

In one embodiment, referring to Figures 1 and 4, the working component 10 further includes a locking member 15 and a displacement sensor mounted on the locking member 15. The locking member 15 is disposed at one end of the shaft assembly 12 away from the permanent magnet assembly 11, and the displacement sensor is used to monitor the motion trajectory of the motor rotor system in the axial and radial directions.

In the disclosed embodiment, the locking members 15 are disposed at both ends of the rotor assembly 1 along the axial direction, and can lock the various working components 10 on the rotor assembly 1 to prevent the working components 10 from axially moving when the rotor assembly 1 rotates at high speed.

Exemplarily, the locking member 15 may be a nut.

In one embodiment, referring to FIG. 1 and FIG. 4 , a positioning stop may be further provided on the outer side of one end of the shaft assembly 12 that cooperates with the locking member 15 .

In the disclosed embodiment, on the basis of locking the working part 10 on the rotor assembly 1 by the locking member 15, the position of the locking member 15 is precisely located, so that the displacement sensor can accurately monitor the motion trajectory of the motor rotor system in the axial and radial directions, and then can intuitively monitor the operating state of the motor rotor system. According to the operating state, the cause of the vibration of the motor rotor system can be further analyzed, the precursor of the fault can be obtained, and timely measures can be taken to prevent the fault from worsening.

The material of the locking member 15 is not limited, and may be, for example, iron, cobalt or nickel. For example, the locking member 15 is made of GH4169 high temperature nickel-based alloy.

On the other hand, an embodiment of the present disclosure provides a permanent magnet motor, comprising the motor rotor system and the stator core 3 as described in any of the aforementioned embodiments.

In one embodiment, referring to FIG. 1 , the length of the permanent magnet assembly 11 along the axial direction is greater than the length of the stator core 3 along the axial direction.

In the disclosed embodiment, since the axial length of the permanent magnet assembly 11 is greater than the axial length of the stator core 3, when the permanent magnet assembly 11 is assembled, the axial length of the stator core 3 will not exceed the axial length range of the permanent magnet assembly 11 due to assembly errors or processing size errors. Subsequently, when the permanent magnet assembly 11 rotates at high speed, no additional axial force will be generated to cause the permanent magnet assembly 11 to move axially, and the permanent magnet assembly 11 has a certain fault tolerance capability.

In one embodiment, referring to FIG. 1 , the permanent magnet motor can be used in an air compressor, and the working component 10 further includes a low-pressure side impeller 161 , a high-pressure side impeller 162 and a thrust plate 17 .

In the disclosed embodiment, the low-pressure side impeller 161 and the high-pressure side impeller 162 are respectively arranged at the two ends of the shaft assembly 12 and locked by the locking member 15, and can rotate together with the shaft assembly 12; the thrust plate 17 is arranged between the supporting device 2 and the high-pressure side impeller 162, and can rotate together with the shaft assembly 12. When the low-pressure side impeller 161 and the high-pressure side impeller 162 rotate together with the shaft assembly 12, the air enters the high-pressure side impeller 162 for secondary compression after being compressed once by the low-pressure side impeller 161. Because the axial thrusts on the impellers on both sides are inconsistent, the rotor assembly 1 tends to move to one side. At this time, the thrust plate 17 plays an axial bearing role to prevent the rotor assembly 1 from deviating to one side.

The material of the low-pressure side impeller 161 and the high-pressure side impeller 162 is not limited, and may be iron, cobalt or nickel, for example. For example, the low-pressure side impeller 161 and the high-pressure side impeller 162 are made of 2A70 aviation aluminum alloy.

The material of the thrust plate 17 is not limited, and may be, for example, iron, cobalt or nickel. For example, the thrust plate 17 is made of GH4169 high temperature nickel-based alloy.

In one embodiment, referring to FIG. 1 and FIG. 2 , the shaft assembly 12 has shaft shoulders at the low-pressure side impeller 161 , the high-pressure side impeller 162 and the thrust plate 17 .

In the disclosed embodiment, the low-pressure side impeller 161 , the high-pressure side impeller 162 and the thrust plate 17 all have shoulders on the shaft assembly 12 to locate the positions of each component, which is beneficial to improving the positioning accuracy of the low-pressure side impeller 161 , the high-pressure side impeller 162 and the thrust plate 17 .

In one embodiment, the end surface of the low-pressure side impeller 161, the end surface of the high-pressure side impeller 162 and the end surface of the thrust plate 17 are all laser-marked for positioning (not shown).

In the disclosed embodiment, laser marking is performed on the end faces of the low-pressure side impeller 161, the high-pressure side impeller 162 and the thrust plate 17 to locate the installation angles of the low-pressure side impeller 161, the high-pressure side impeller 162 and the thrust plate 17 after the rotor assembly 1 is assembled and tested for balancing. This allows for rapid repeated radial positioning when the rotor assembly 1 is reinstalled after being disassembled for maintenance or the like, thereby ensuring consistency before and after reinstallation of the rotor assembly 1 and avoiding changes in the imbalance amount when the rotor assembly 1 is reinstalled, which may affect the stability of the rotor assembly 1.

In one embodiment, referring to FIG. 1 and FIG. 2 , outer hexagonal square heads 1211 may be provided at both ends of the shaft body 121 in the axial direction to facilitate installation of the locking member 15 .

In the embodiment of the present disclosure, by providing the outer hexagonal square heads 1211 on both sides of the shaft body 121 in the axial direction, when the locking member 15 is installed at one end of the shaft body 12 in the axial direction, the outer hexagonal square head 1211 at the other end can be used to fix the rotor assembly 1, so that the locking member 15 reaches a preset locking force. In addition, since there is no need to use a puller to install the locking member 15, the two ends of the shaft body 121 in the axial direction can be thinned, which is beneficial to the weight reduction of the rotor assembly 1 and also facilitates the flexible design of the impeller.

For example, referring to FIG. 1 and FIG. 2 , when installing the locking member 15 at the left end of the shaft body 121, The outer hexagonal square head 1211 at the right end of the shaft body 121 is clamped with a wrench so that the rotor assembly 1 does not rotate before the locking member 15 reaches a preset locking force. Similarly, when installing the locking member 15 at the right end of the shaft body 121, the outer hexagonal square head 1211 at the left end of the shaft body 121 is clamped with a wrench so that the rotor assembly 1 does not rotate before the locking member 15 reaches a preset locking force.

Referring to FIG. 5 , a third aspect of the embodiment of the present disclosure provides a method for manufacturing a motor rotor system. The rotor assembly 1 includes a working component 10 and a permanent magnet component 11. The working component 10 includes a sleeve 13 and a shaft component 12. The manufacturing method includes:

Step S1, using the outer peripheral surface of the permanent magnet assembly 11 as a radial positioning reference, and sleeve the sheath 13 on the permanent magnet assembly 11;

Step S2, taking the sleeve 13 as an axial positioning reference, determining the position of the shaft assembly 12 relative to the sleeve 13 along the axial direction of the sleeve 13.

The manufacturing method of the motor rotor system provided in the embodiment of the present disclosure is suitable for high-speed permanent magnet motors. The outer peripheral surface of the permanent magnet component 11 is used as the radial positioning reference, and the sleeve 13 is used as the axial positioning reference. The rotor assembly 1 is assembled and fine-processed to ensure the dimensional tolerance and position tolerance of the rotor assembly 1, so that the distances from the center of gravity 1a of the rotor assembly 1 to the first support rotation center 1b and the second support rotation center 1c are equal, thereby improving the stability of the rotor assembly 1 during high-speed rotation.

The control method of the embodiment of the present disclosure is described in detail below in conjunction with specific embodiments.

Exemplarily, before step S1 , the manufacturing method includes: grinding the outer peripheral surface of the permanent magnet component 11 to improve the processing accuracy of the permanent magnet component 11 .

Exemplarily, in step S1 , the permanent magnet assembly 11 is interference-fitted into the sleeve 13 with the outer circumferential surface of the permanent magnet assembly 11 as a reference, so that there is no gap between the matching surfaces of the permanent magnet assembly 11 and the sleeve 13 .

Exemplarily, the interference fit between the permanent magnet assembly 11 and the sheath 13 is 0.01 to 0.014 mm.

Illustratively, before step S2, the manufacturing method includes: further grinding the shaft assembly to improve the machining accuracy of the shaft assembly.

Exemplarily, in step S2, the relative position of the shaft assembly 12 and the sleeve 13 in the axial direction is determined with the sleeve 13 as the axial positioning reference to ensure the assembly accuracy of the shaft assembly 12 and the sleeve 13 so that the shaft assembly 12 and the sleeve 13 are as coaxial as possible.

Exemplarily, after step S2, the shaft assembly 12 and the sleeve 13 are laser welded to form an integral body.

Exemplarily, the fusion welding depth of the shaft assembly 12 and the sheath 13 by laser welding is 3 mm.

In one embodiment, the permanent magnet assembly 11 specifically includes:

Step S11 , a plurality of disc-shaped permanent magnets 111 are bonded together to form the cylindrical permanent magnet assembly 11 .

Specifically, the permanent magnet assembly 11 is composed of a plurality of disk-shaped permanent magnets 111 with consistent magnetic field orientations bonded together, which is firm and reliable.

The above description is only a preferred embodiment of the present disclosure and is not intended to limit the present disclosure. For those skilled in the art, the present disclosure may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present disclosure shall be included in the protection scope of the present disclosure.

Claims (16)

A motor rotor system, comprising: A support device having a first support rotation center and a second support rotation center arranged at intervals; The rotor assembly is rotatably connected to the support device at the first support rotation center and the second support rotation center, respectively. The rotor assembly rotates around a line connecting the first support rotation center and the second support rotation center. The distance between the first support rotation center and the center of gravity of the rotor assembly is a first distance. The distance between the second support rotation center and the center of gravity of the rotor assembly is a second distance. The first distance is equal to the second distance. The motor rotor system according to claim 1, wherein a midpoint of a line connecting the first support rotation center and the second support rotation center coincides with a center of gravity of the rotor assembly. The motor rotor system according to claim 1 or 2, wherein the supporting device comprises two support members arranged at an interval, the first support rotation center is formed at one of the support members, and the second support rotation center is formed at the other of the support members. The motor rotor system according to any one of claims 1 to 3, wherein the rotor assembly comprises: A working component having a receiving cavity; A permanent magnet component is installed in the accommodating cavity, and the permanent magnet component is a solid structure. The motor rotor system according to claim 4, wherein the permanent magnet assembly comprises a plurality of stacked permanent magnets and an insulating layer arranged between two adjacent permanent magnets, and the permanent magnet is configured in a disc shape. The motor rotor system according to claim 4 or 5, wherein the working component comprises: jacket; A shaft assembly, wherein the shaft assembly is respectively arranged at two axial ends of the sleeve, and the sleeve and the shaft assembly surround the accommodating cavity. The motor rotor system according to claim 6, wherein the sleeve is welded to the shaft assembly; and/or the permanent magnet assembly is located in the sleeve, and the sleeve and the permanent magnet assembly are interference fit. The motor rotor system according to claim 6 or 7, wherein the shaft assembly has a weight-reducing hole, and the weight-reducing hole is formed at one end of the shaft assembly close to the permanent magnet assembly. The electric machine rotor system according to claim 8, wherein the shaft assembly comprises: A shaft body, wherein the weight-reducing hole is formed in the shaft body; A sealing cover is arranged between the shaft body and the permanent magnet assembly to close the weight-reducing hole. The motor rotor system according to claim 8 or 9, wherein the shaft assembly further has an exhaust hole connected to the outside world, so as to connect the weight-reducing hole to the outside world. The motor rotor system according to claim 10, wherein the number of the exhaust holes is at least two, and the exhaust holes are arranged in pairs along the radial direction of the shaft assembly; and/or, The exhaust hole is arranged to be inclined along the radial direction of the shaft assembly, and the inclination direction of the exhaust hole is the same as the rotation direction of the shaft assembly. According to any one of claims 6 to 11, the working component further comprises a locking member and a displacement sensor mounted on the locking member, the locking member is arranged at an end of the shaft assembly away from the permanent magnet assembly, and the displacement sensor is used to monitor the axial and radial motion trajectory of the motor rotor system. A permanent magnet motor, comprising: The motor rotor system according to any one of claims 1 to 12; Stator core. The permanent magnet motor according to claim 13, wherein the length of the permanent magnet assembly along the axial direction is greater than the length of the stator core along the axial direction. A method for manufacturing a motor rotor system, wherein the rotor assembly comprises a working component and a permanent magnet component, wherein the working component comprises a sleeve and a shaft component, and the manufacturing method comprises: Taking the outer peripheral surface of the permanent magnet assembly as a radial positioning reference, the sheath is sleeved on the permanent magnet assembly; The position of the shaft assembly relative to the sleeve along the axial direction of the sleeve is determined by taking the sleeve as an axial positioning reference. The manufacturing method according to claim 15, wherein the permanent magnet assembly specifically comprises: A plurality of disc-shaped permanent magnets are bonded together to form the cylindrical permanent magnet assembly.