Rotor assembly, motor and compressor
By mixing rare earth permanent magnets and non-rare earth permanent magnets in the motor and optimizing the motor structural design, the problem of high rare earth permanent magnet usage is solved, and the efficiency of reducing the rare earth permanent magnet usage is achieved while maintaining the motor performance.
Patent Information
- Application Number
- CN202421731304.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-19
- Publication Date
- 2025-04-25
- Estimated Expiration
- 2034-07-19
AI Technical Summary
Due to limited rare earth resources, rare earth permanent magnet motors need to reduce the amount of rare earth permanent magnets while maintaining the efficiency of motor performance.
By mixing rare earth permanent magnets and non-rare earth permanent magnets in the rotor assembly, and by optimizing the motor structural design, including providing a plurality of pairs of first magnets and second magnets to be spaced along the circumference of the rotor core, a magnetic barrier is provided between the first magnet and the second magnet, forming an inner magnetic bridge to guide the magnetic flux.
It has achieved the significant reduction in the use of rare earth permanent magnets, improve the utilization rate of magnets, reduce magnetic leakage, and improve the magnetic flux and performance of the motor while ensuring the unchanged performance of the motor.
Smart Images
Figure CN222802617U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of motors, in particular to a rotor assembly, a motor and a compressor. Background Art
[0002] At present, permanent magnet motors have the advantages of simple structure, reliability, high efficiency and high power density, and are widely used. Among them, thanks to the high magnetic energy product of rare earth permanent magnets, the performance of rare earth permanent magnet motors is excellent. However, the reserves of rare earth resources are very limited, and the home appliance manufacturing industry should actively respond to the national call to reduce its dependence on rare earth permanent magnets. Completely replacing rare earth permanent magnets with non-rare earth permanent magnets will cause serious deterioration in motor performance. Therefore, the mixed use of rare earth permanent magnets and non-rare earth permanent magnets has become an important research direction, which can greatly reduce the amount of rare earth permanent magnets while ensuring the high performance of permanent magnet motors. Among them, how to further expand the reduction of rare earth permanent magnets through motor structure optimization design has become a current research hotspot. Utility Model Content
[0003] The main purpose of the utility model is to provide a rotor assembly, a motor and a compressor, aiming to provide a motor which can improve the utilization rate of magnetic steel while reducing the amount of rare earth permanent magnets.
[0004] To achieve the above objectives, the rotor assembly proposed by the utility model includes:
[0005] a rotor core; and,
[0006] A plurality of pairs of first magnets and a plurality of second magnets are arranged at intervals along the circumference of the rotor core, a second magnet is arranged between each pair of the first magnets, both ends of each pair of the first magnets and the second magnets in the length direction are arranged along the axial direction of the rotor core, both sides of each pair of the first magnets in the width direction are arranged along the radial direction of the rotor core, and both ends of each second magnet in the width direction are arranged along the circumference of the rotor core, each pair of the first magnets are arranged away from each other in a direction away from the middle of the rotor core, and one end of the first magnet in the width direction and close to the middle of the rotor core protrudes from the second magnet;
[0007] Wherein, a plurality of magnetic barriers are further arranged on the rotor core, and each of the magnetic barriers is arranged between the first magnet and the second magnet that are adjacently arranged.
[0008] In one embodiment, one end of each magnetic barrier is disposed adjacent to one side end of the first magnet in the width direction close to the middle of the rotor core, and the other end is disposed adjacent to one side end of the second magnet in the width direction close to the first magnet.
[0009] In one embodiment, an angle α is formed between two adjacent pairs of the first magnets, and 0°<α≤90°.
[0010] In one embodiment, an internal magnetic bridge is defined between two magnetic barriers adjacent to the first magnets, and a width of the internal magnetic bridge is d, and 0.3 mm≤d≤3 mm.
[0011] In one embodiment, the inner magnetic bridge is at least partially disconnected in the axial direction of the rotor core.
[0012] In one embodiment, a separator is provided at the disconnection point of the internal magnetic bridge, and the material of the separator is set to be a non-magnetic material.
[0013] In one embodiment, the maximum magnetic energy product of the first magnet is set to be greater than the maximum magnetic energy product of the second magnet.
[0014] In one embodiment, the material of the first magnet is set to be a rare earth permanent magnet; and / or,
[0015] The material of the second magnet is set to be ferrite.
[0016] In one embodiment, a plurality of pairs of the first magnets are centrally symmetrically arranged about the center of the rotor core; and / or,
[0017] The plurality of second magnets are centrally symmetrically arranged about the center of the rotor core.
[0018] In one embodiment, the first magnet is configured as a rectangular parallelepiped; and / or the second magnet is configured as a rectangular parallelepiped.
[0019] The utility model also provides a motor, the motor comprising a rotor assembly, the rotor assembly comprising:
[0020] a rotor core; and,
[0021] A plurality of pairs of first magnets and a plurality of second magnets are arranged at intervals along the circumference of the rotor core, a second magnet is arranged between each pair of the first magnets, both ends of each pair of the first magnets and the second magnets in the length direction are arranged along the axial direction of the rotor core, both sides of each pair of the first magnets in the width direction are arranged along the radial direction of the rotor core, and both ends of each second magnet in the width direction are arranged along the circumference of the rotor core, each pair of the first magnets are arranged away from each other in a direction away from the middle of the rotor core, and one end of the first magnet in the width direction and close to the middle of the rotor core protrudes from the second magnet;
[0022] Wherein, a plurality of magnetic barriers are further arranged on the rotor core, and each of the magnetic barriers is arranged between the first magnet and the second magnet that are adjacently arranged.
[0023] The utility model also provides a compressor, the compressor comprising a motor, the motor comprising a rotor assembly, the rotor assembly comprising:
[0024] a rotor core; and,
[0025] A plurality of pairs of first magnets and a plurality of second magnets are arranged at intervals along the circumference of the rotor core, a second magnet is arranged between each pair of the first magnets, both ends of each pair of the first magnets and the second magnets in the length direction are arranged along the axial direction of the rotor core, both sides of each pair of the first magnets in the width direction are arranged along the radial direction of the rotor core, and both ends of each second magnet in the width direction are arranged along the circumference of the rotor core, each pair of the first magnets are arranged away from each other in a direction away from the middle of the rotor core, and one end of the first magnet in the width direction and close to the middle of the rotor core protrudes from the second magnet;
[0026] Wherein, a plurality of magnetic barriers are further arranged on the rotor core, and each of the magnetic barriers is arranged between the first magnet and the second magnet that are adjacently arranged.
[0027] In the technical solution of the utility model, an angle area is formed between each pair of the first magnets, and the space of the angle area gradually increases in the direction away from the middle of the rotor core. The second magnet can be translated in the direction away from the middle of the rotor core, so that the space for accommodating the second magnet is larger, and the second magnet can be set to a wider size, thereby improving the magnetic flux and performance of the motor, and the second magnet is correspondingly set in the middle position in the width direction close to the first magnet. The distance between the two side ends of the second magnet in the width direction and the two first magnets on both sides is increased, so that the area is prone to leakage magnetic field, and a magnetic barrier is set between the adjacent first magnet and the second magnet to block the path of the nearby closed leakage magnetic field to reduce the leakage magnetic field. BRIEF DESCRIPTION OF THE DRAWINGS
[0028] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.
[0029] Figure 1A schematic structural diagram of an embodiment of a rotor assembly provided by the utility model;
[0030] Figure 2 for Figure 1 Schematic diagram of the angles of the two first magnets, and the positions of the first magnet and the second magnet.
[0031] Description of Figure Numbers:
[0032] 100. Rotor assembly; 1. rotor core; 2. first magnet; 3. second magnet; 4. magnetic barrier; 5. internal magnetic bridge.
[0033] The realization of the purpose, functional features and advantages of the utility model will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION
[0034] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.
[0035] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back...), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components in a certain specific posture. If the specific posture changes, the directional indications will also change accordingly.
[0036] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the utility model, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features limited to "first" and "second" may explicitly or implicitly include at least one of the features. In addition, if "and / or" or "and / or" appears in the full text, its meaning includes three parallel solutions. Taking "A and / or B" as an example, it includes solution A, solution B, or solutions that satisfy both A and B. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the utility model.
[0037] At present, permanent magnet motors have the advantages of simple structure, reliability, high efficiency and high power density, and are widely used. Among them, thanks to the high magnetic energy product of rare earth permanent magnets, the performance of rare earth permanent magnet motors is excellent. However, the reserves of rare earth resources are very limited, and the home appliance manufacturing industry should actively respond to the national call to reduce its dependence on rare earth permanent magnets. Completely replacing rare earth permanent magnets with non-rare earth permanent magnets will cause serious deterioration in motor performance. Therefore, the mixed use of rare earth permanent magnets and non-rare earth permanent magnets has become an important research direction, which can greatly reduce the amount of rare earth permanent magnets while ensuring the high performance of permanent magnet motors. Among them, how to further expand the reduction of rare earth permanent magnets through motor structure optimization design has become a current research hotspot.
[0038] The utility model provides a rotor assembly, aiming to provide a motor which can improve the utilization rate of magnetic steel while reducing the usage of rare earth permanent magnets.
[0039] See also Figure 1 to Figure 2 In one embodiment of the utility model, the rotor assembly 100 includes a rotor core 1, a plurality of pairs of first magnets 2 and a plurality of second magnets 3, which are arranged at intervals along the circumference of the rotor core 1, and a second magnet 3 is arranged between each pair of the first magnets 2. The two ends in the length direction of each first magnet 2 and each pair of the second magnets 3 are arranged along the axial direction of the rotor core 1, and the two side ends in the width direction of each pair of the first magnets 2 are arranged along the radial direction of the rotor core 1. The two ends in the width direction of each second magnet 3 are arranged along the circumference of the rotor core 1. Each pair of the first magnets 2 is arranged away from each other in a direction away from the middle of the rotor core 1, and one end of the first magnet 2 in the width direction and close to the middle of the rotor core 1 protrudes from the second magnet 3; wherein, a plurality of magnetic barriers 4 are also arranged on the rotor core 1, and each of the magnetic barriers 4 is arranged between the first magnets 2 and the second magnets 3 that are adjacently arranged.
[0040] It should be noted that the rotor core 1 has a plurality of mounting grooves for installing the plurality of first magnets 2 and the plurality of second magnets 3, each of the mounting grooves extending along the axial direction of the rotor core 1, and the plurality of mounting grooves include a plurality of first mounting grooves and a plurality of second mounting grooves, the plurality of first mounting grooves being provided for corresponding installation of the plurality of first magnets 2, and the plurality of second mounting grooves being provided for corresponding installation of the plurality of second magnets 3.
[0041] The first magnet 2 is arranged in the length direction of the first magnet 2 in the thickness direction of the rotor core 1, the first magnet 2 is arranged in the width direction of the first magnet 2 in the radial direction along the rotor core 1, and the first magnet 2 is arranged in the thickness direction of the first magnet 2 in the circumferential direction along the rotor core 1.
[0042] The second magnet 3 is arranged in the length direction of the second magnet 3 in the thickness direction of the rotor core 1, the second magnet 3 is arranged in the thickness direction of the second magnet 3 in the radial direction along the rotor core 1, and the second magnet 3 is arranged in the width direction of the second magnet 3 in the circumferential direction along the rotor core 1.
[0043] It can be understood that in the related art, the second magnet is arranged near the inner end of each pair of first magnets near the rotor core to form an end-adjacent form. Then, in the area between the two magnets, when an iron core is provided, its width is also narrow, and it is easy to be magnetically saturated, thereby suppressing magnetic leakage. In the technical solution of the present application, each pair of the first magnets 2 are arranged away from each other in the direction away from the rotor core 1, and the second magnet 3 is moved away from the middle of the rotor core 1 by a certain distance, so that the first magnet 2 is in the area in the width direction and close to the middle of the rotor core 1 (i.e., R1 < R2), and after the second magnet 3 is arranged, the second magnet 3 is correspondingly arranged in the middle position in the width direction close to the first magnet 2, and the spacing distance between the two side ends of the second magnet 3 in the width direction and the two first magnets 2 on both sides is increased. If the spacing area is provided with an iron core or other magnetically conductive materials, it will cause a lot of magnetic leakage, and the magnetic leakage can be directly closed at both ends of the permanent magnet, thereby reducing the magnetic flux of the rotor assembly 100.
[0044] It should be noted that the magnetic barrier 4 is a structure specially designed in the motor rotor or stator, and its purpose is to control the magnetic flux path and optimize the motor performance. The magnetic barrier 4 is usually made of non-magnetic or low-permeability materials, such as air, plastic or other non-magnetic materials, which can significantly increase the magnetic resistance of the magnetic flux passing through the area. Of course, the magnetic barrier 4 can also be a slot set on the rotor core 1.
[0045] In the technical solution of the utility model, an angle area is formed between each pair of the first magnets 2, and the space of the angle area gradually increases in the direction away from the middle of the rotor core 1. The second magnet 3 can be translated in the direction away from the middle of the rotor core 1, so that the space for accommodating the second magnet 3 is larger, and the second magnet 3 can be set to a wider size, thereby improving the magnetic flux and performance of the motor. The second magnet 3 is correspondingly arranged at a middle position close to the first magnet 2 in the width direction, and the distance between the two side ends of the second magnet 3 in the width direction and the two first magnets 2 on both sides is increased, so that this area is prone to leakage magnetic field. By arranging a magnetic barrier 4 between the adjacent first magnet 2 and the second magnet 3, the path of the nearby closed leakage magnetic field is blocked to reduce the leakage magnetic field.
[0046] In order to prevent leakage magnetic flux from directly passing through the rotor core 1 and closing directly at both ends of the permanent magnet to form a longer closed path, in the present embodiment, one end of each magnetic barrier 4 is adjacent to one side end of the first magnet 2 in the width direction close to the middle of the rotor core 1, and the other end is adjacent to one side end of the second magnet 3 in the width direction close to the first magnet 2.
[0047] It can be understood that when the magnetic barrier 4 is set as a slot body, the magnetic barrier 4 can be connected to the first installation slot for installing the first magnet 2, and can also be connected to the second installation slot for installing the second magnet 3, so that a magnetic barrier 4 is formed between the first magnet 2 and the second magnet 3.
[0048] With such a configuration, the magnetic barrier 4 can force the magnetic flux to flow along a predetermined path, that is, through the air gap and the stator core, rather than being directly closed inside the rotor core 1, thereby reducing ineffective leakage magnetic flux and increasing effective magnetic flux involved in electromechanical energy conversion, thereby improving the efficiency and power density of the motor. In addition, the magnetic barrier 4 avoids the saturation of the rotor core 1 in this area, keeps the magnetic flux density within a reasonable range, and thus maintains stable motor performance. At the same time, the magnetic barrier 4 can help control the magnetic flux distribution, making the magnetic field more uniform, so that the permanent magnet motor can output torque more smoothly, reduce torque pulsation and vibration, and improve the running quality of the motor.
[0049] Furthermore, in this embodiment, an angle α is formed between two adjacent pairs of the first magnets 2, and 0°<α≤90°. Thus, the angle α is set within the range of 0° to 90°, so that the utilization rate of the first magnet 2 is high. If the angle α is set too large, it will cause local magnetic saturation of the magnetic circuit, making the magnetic circuit design unreasonable.
[0050] Furthermore, in this embodiment, an inner magnetic bridge 5 is defined between the two magnetic barriers 4 respectively adjacent to the pair of first magnets 2 , and the width of the inner magnetic bridge 5 is d, 0.3 mm≤d≤3 mm.
[0051] The inner magnetic bridge 5 is a part of the rotor core 1 structure. The width of the inner magnetic bridge 5 is set within a size range of 0.3 mm to 3 mm to guide the magnetic flux to flow more effectively from one magnetic pole to another, so that the magnetic flux is more inclined to flow along a preset path rather than through the shortest path of the core, directly passing through the rotor core, reducing unnecessary leakage flux, and ensuring that most of the magnetic flux can be transmitted through the air gap to participate in the generation of electromagnetic torque, thereby improving the utilization of the magnetic flux and the efficiency of the motor.
[0052] If the width of the inner magnetic bridge 5 is too small, the rotor strength may be insufficient, thus affecting the life and reliability of the motor.
[0053] If the width of the inner magnetic bridge 5 is too large, magnetic leakage will increase, thereby reducing the efficiency, power density and performance of the motor.
[0054] Of course, the internal magnetic bridge 5 not only has an electromagnetic effect, but also can increase the mechanical strength and rigidity of the rotor. It can be understood that as long as the internal magnetic bridge 5 exists, the leakage magnetic flux will increase, resulting in a decrease in the utilization rate of the permanent magnet. Considering the need to take into account the rotor structural strength, in this embodiment, the internal magnetic bridge 5 is at least partially disconnected in the axial direction of the rotor core 1. In this way, a part of the internal magnetic bridge 5 is retained, so that the rotor assembly 100 can meet the strength requirements in terms of mechanical strength and can reduce the rotor leakage magnetic flux to a certain extent.
[0055] It can be understood that the rotor core 1 is generally composed of a plurality of rotor punchings stacked together. Thus, when processing each of the rotor punchings, the area corresponding to the internal magnetic bridge 5 on some of the rotor punchings can be set to be disconnected, while the area corresponding to the internal magnetic bridge 5 on some of the rotor punchings can be set to be connected and closed. When a plurality of the rotor punchings are stacked, the internal magnetic bridge 5 can be at least partially disconnected in the axial direction of the rotor core 1.
[0056] Furthermore, in order to ensure the structural strength of the rotor core 1 at the disconnection point, in this embodiment, a partition is provided at the disconnection point of the internal magnetic bridge 5, and the material of the partition is set to be a non-magnetic material. In this way, the partition of the non-magnetic material can prevent or reduce the direct closure of the magnetic flux inside the rotor, force the magnetic flux to pass through the air gap and the stator core, optimize the magnetic flux path, reduce magnetic leakage, and provide additional mechanical support to enhance the structural stability of the rotor. In addition, some non-magnetic materials also have good thermal insulation properties and can be used as a thermal isolation layer to help thermal management inside the motor.
[0057] In this embodiment, the magnetic energy product of the first magnet 2 is set to be greater than the magnetic energy product of the second magnet 3 .
[0058] It should be noted that the maximum magnetic energy product (BHmax) is an indicator of the magnetic energy that a magnet can store at a specific working point, which reflects the performance level of the magnet. The larger the magnetic energy product, the stronger the magnetic performance of the magnet under the same volume.
[0059] It should also be noted that during the operation of the motor, the outer magnet closest to the stator winding is most affected by the armature reaction magnetic field. Placing the first magnet 2 with a higher magnetic energy product on the outside can ensure that the anti-demagnetization performance of the magnet meets the requirements and improve reliability.
[0060] In the related art, the first magnet with high performance is used on the outside, while the second magnet with lower cost is used on the inside, which can balance the performance and cost and reduce the overall manufacturing cost of the motor.
[0061] In this embodiment, the material of the first magnet 2 is set to be rare earth permanent magnet; and / or the material of the second magnet 3 is set to be ferrite.
[0062] The first magnet 2 is set as a rare earth permanent magnet, and its maximum magnetic energy product is usually greater than 200 kJ / m 3 The material of the second magnet 3 is ferrite, and the maximum magnetic energy product is usually less than 100kJ / m 3 .
[0063] It should be noted that rare earth permanent magnet materials are generally neodymium iron boron (NdFeB) and samarium cobalt (SmCo), and of course other permanent magnet materials containing rare earth elements can also be used. In addition to ferrite, the material of the second magnet 3 can also be manganese aluminum (MnAl), aluminum nickel cobalt (AlNiCo), iron cobalt (FeCo), etc.
[0064] Furthermore, in the present embodiment, a plurality of pairs of the first magnets 2 are centrally symmetrically arranged about the center of the rotor core 1; and / or, the plurality of second magnets 3 are centrally symmetrically arranged about the center of the rotor core 1. In this way, the centrally symmetrical magnet layout helps to form a uniform magnetic field, reduces the magnetic imbalance inside the motor, and avoids vibration and noise during the operation of the motor. In a permanent magnet synchronous motor, torque is generated by the interaction between the stator current and the magnetic field generated by the permanent magnet. The symmetrical magnet layout ensures that this interaction is balanced no matter what position the rotor rotates to, thereby providing a smooth torque.
[0065] Therefore, arranging multiple pairs of the first magnets 2 in a centrally symmetrical manner about the center of the rotor core 1; and / or arranging the multiple second magnets 3 in a centrally symmetrical manner about the center of the rotor core 1 not only improves the dynamic response and stability of the motor, but also simplifies the control logic and reduces maintenance and operating costs.
[0066] Furthermore, in order to facilitate manufacturing and reduce manufacturing costs, in the present embodiment, the first magnet 2 is configured as a rectangular parallelepiped; and / or the second magnet 3 is configured as a rectangular parallelepiped.
[0067] The utility model also proposes a motor, which includes a stator assembly and a rotor assembly 100. The specific structure of the rotor assembly 100 refers to the above embodiment. Since the motor adopts all the technical solutions of all the above embodiments, it has at least all the beneficial effects brought by the technical solutions of the above embodiments, which will not be described one by one here.
[0068] The utility model also proposes a compressor, which includes a motor. The specific structure of the motor refers to the above embodiment. Since the compressor adopts all the technical solutions of all the above embodiments, it has at least all the beneficial effects brought by the technical solutions of the above embodiments, which will not be described one by one here.
[0069] The above description is only an exemplary embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the technical concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.
Claims
1. A rotor assembly, characterized in that: include: Rotor core; as well as, A plurality of pairs of first magnets and a plurality of second magnets are arranged at intervals along the circumference of the rotor core, a second magnet is arranged between each pair of the first magnets, both ends of each pair of the first magnets and the second magnets in the length direction are arranged along the axial direction of the rotor core, both sides of each pair of the first magnets in the width direction are arranged along the radial direction of the rotor core, and both ends of each second magnet in the width direction are arranged along the circumference of the rotor core, each pair of the first magnets are arranged away from each other in a direction away from the middle of the rotor core, and one end of the first magnet in the width direction and close to the middle of the rotor core protrudes from the second magnet; Wherein, a plurality of magnetic barriers are further arranged on the rotor core, and each of the magnetic barriers is arranged between the first magnet and the second magnet that are adjacently arranged.
2. The rotor assembly according to claim 1, characterized in that One end of each magnetic barrier is disposed adjacent to one side end of the first magnet in the width direction close to the middle of the rotor core, and the other end is disposed adjacent to one side end of the second magnet in the width direction close to the first magnet.
3. The rotor assembly according to claim 1 or 2, characterized in that: An angle α is formed between two adjacent pairs of the first magnets, and 0°<α≤90°.
4. The rotor assembly according to claim 1, wherein: An inner magnetic bridge is defined between two magnetic barriers adjacent to the first magnets respectively, and the width of the inner magnetic bridge is d, 0.3 mm≤d≤3 mm.
5. The rotor assembly according to claim 4, characterized in that The inner magnetic bridge is at least partially disconnected in the axial direction of the rotor core.
6. The rotor assembly according to claim 5, characterized in that A partition is provided at the disconnection point of the inner magnetic bridge, and the material of the partition is set to be a non-magnetic material.
7. The rotor assembly according to any one of claims 1 to 6, characterized in that: The maximum magnetic energy product of the first magnet is set to be greater than the maximum magnetic energy product of the second magnet.
8. The rotor assembly according to claim 7, characterized in that The material of the first magnet is set to be rare earth permanent magnet; and / or, The material of the second magnet is set to be ferrite.
9. The rotor assembly according to claim 1, wherein: A plurality of pairs of the first magnets are centrally symmetrically arranged about the center of the rotor core; and / or, The plurality of second magnets are centrally symmetrically arranged about the center of the rotor core.
10. The rotor assembly according to claim 1, wherein: The first magnet is configured as a rectangular parallelepiped; and / or the second magnet is configured as a rectangular parallelepiped.
11. A motor, characterized in that: Comprising a rotor assembly as claimed in any one of claims 1 to 10.
12. A compressor, characterized in that: Comprising the motor as claimed in claim 11.