Rotors, motors and compressors

Abstract

In the rotor, motor, and compressor, the rotor includes a rotor core (100), a first permanent magnet (200), and a second permanent magnet (300). The rotor core (100) is provided with a plurality of first insertion grooves (130) and a plurality of second insertion grooves (140) that are alternately arranged along the circumferential direction of the rotor core (100). The first permanent magnets (200) are provided in a number that matches the number of the first insertion grooves (130), and the first permanent magnets (200) are attached correspondingly within the first insertion grooves (130), and the magnetization direction of the first permanent magnets (200) is along the radial direction of the rotor core (100). A plurality of second permanent magnets (300) are provided, the number of which corresponds to the number of the second insertion grooves (140), the second permanent magnets (300) are attached to the corresponding second insertion grooves (140), the magnetization direction of the second permanent magnets (300) is along the tangential direction of the rotor core (100), and when a plane perpendicular to the magnetization direction of the second permanent magnets (300) is taken as a projection plane, the projections of the second permanent magnets (300) and the adjacent first permanent magnets (200) onto the projection plane at least partially overlap.

Description

[Technical Field]

[0001] This application claims priority to a Chinese patent application filed on March 7, 2023, bearing application number 202310234331.0 and entitled "Rotor, Motor and Compressor," the entire contents of which are incorporated herein by reference.

[0002] The present application relates to the technical field of compressors, and in particular to rotors, motors and compressors. [Background technology]

[0003] In related art, the rotor of a ferrite permanent magnet motor generally adopts a spoke structure, which can achieve a certain amplitude value of the air gap magnetic field strength of the motor. To support the permanent magnets, narrow rotor support beams are generally installed in the rotor, and the support beams are located in the openings between adjacent permanent magnets. However, the support beams also provide a magnetic leakage path between adjacent poles of the permanent magnets, which causes a certain attenuation of the air gap magnetic field amplitude value and reduces the performance of the motor. Summary of the Invention [Problem to be solved by the invention]

[0004] The present application aims to solve at least one of the technical problems existing in the prior art, and to that end, the present application provides a rotor, and a motor and a compressor including the rotor. [Means for solving the problem]

[0005] A rotor according to an embodiment of the first aspect of the present application includes a rotor core, a first permanent magnet, and a second permanent magnet, the rotor core being provided with a plurality of first insertion grooves and a plurality of second insertion grooves, the first insertion grooves and the second insertion grooves being arranged alternately along the circumferential direction of the rotor core, a plurality of first permanent magnets being provided and the number of the first permanent magnets is the same as the number of the first insertion grooves, the first permanent magnets are installed in corresponding ones of the first insertion grooves, the magnetization direction of the first permanent magnets is along the radial direction of the rotor core, a plurality of second permanent magnets being provided and the number of the second permanent magnets is the same as the number of the second insertion grooves, the second permanent magnets are installed in corresponding ones of the second insertion grooves, the magnetization direction of the second permanent magnets is along the tangential direction of the rotor core, and when a plane perpendicular to the magnetization direction of the second permanent magnet is taken as a projection plane, projections of the second permanent magnet and the adjacent first permanent magnet onto the projection plane at least partially overlap.

[0006] According to some embodiments of the present application, the cross section of the first permanent magnet is rectangular, and an opposing surface is provided at the end of the second permanent magnet facing the first permanent magnet, and the opposing surface is parallel to the opposing side surface of the first permanent magnet.

[0007] According to some embodiments of the present application, the remanence of the first permanent magnet and the second permanent magnet ranges from 0.2T to 0.7T.

[0008] According to some embodiments of the present application, the sum of the cross-sectional area of ​​the plurality of first permanent magnets and the cross-sectional area of ​​the plurality of second permanent magnets is 50% or more of the cross-sectional area of ​​the rotor core.

[0009] According to some embodiments of the present application, the rotor core includes an inner ring portion and a plurality of outer core portions, the plurality of outer core portions being spaced apart along the outer periphery of the inner ring portion, the first insertion groove being formed between the outer core portion and the inner ring portion, and the second insertion groove being formed between adjacent outer core portions.

[0010] According to some embodiments of the present application, a magnetic bridge is provided between the adjacent first insertion groove and the adjacent second insertion groove, and the outer core portion and the inner ring portion are connected via the magnetic bridge, or the magnetic bridge is installed by cutting.

[0011] According to some embodiments of the present application, the rotor further includes a connecting member and end plates located at both ends of the rotor core, the outer core portion is provided with a through hole installed along the axial direction of the rotor core, and the connecting member passes through the through hole to connect the end plates at both ends.

[0012] According to some embodiments of the present application, protrusions extending toward the second insertion groove are provided on both ends of the outer core portion, and recesses are provided on both sides of the second permanent magnet, with the protrusions and recesses engaging with each other to regulate the position of the second permanent magnet along the radial direction of the rotor core.

[0013] According to some embodiments of the present application, the end face of the outer core portion away from the inner annular portion is an arcuate surface, and the center of the arcuate surface and the center of the inner annular portion are non-concentrically disposed.

[0014] A motor according to an embodiment of the second aspect of the present application includes a stator and the rotor according to the embodiment of the first aspect, wherein the rotor is rotatably disposed within the stator.

[0015] A compressor according to an embodiment of the third aspect of the present application includes the motor according to the embodiment of the second aspect.

[0016] Additional features and advantages of the present application will be set forth in the description that follows, and in part will be obvious from the description, or may be learned by the practice of the present application. [Brief explanation of the drawings]

[0017] [Figure 1] 1 is a schematic diagram of the overall structure of a rotor according to an embodiment of the present application; [Figure 2] 1 is a schematic cross-sectional view of a rotor according to an embodiment of the present application; [Figure 3] FIG. 3 is an enlarged schematic structural view of a portion A in FIG. 2. [Figure 4] 1 is a schematic diagram of an assembly structure of a rotor core and an end plate according to an embodiment of the present application. [Figure 5] 1 is a schematic cross-sectional view of a motor according to an embodiment of the present application; [Figure 6] 2 is a schematic diagram of the distribution of magnetic field lines of the magnetic field of the motor according to an embodiment of the present application; [Figure 7] FIG. 1 is a comparison diagram of the results of fast Fourier transform (FFT) of the air gap magnetic field between the conventional solution and the present application. [Figure 8] 1 is a diagram showing the distribution of magnetic flux density in a series magnetic path of a conventional solution and a series-parallel magnetic path of the present application; DETAILED DESCRIPTION OF THE INVENTION

[0018] The following detailed description of the embodiments of the present application is provided below, and examples of the embodiments are shown in the drawings, in which the same or similar symbols throughout represent the same or similar elements, or elements having the same or similar functions. The following embodiments described with reference to the drawings are merely illustrative and are intended to help interpret the present application, and should not be construed as limitations on the present application.

[0019] In the description of this application, the orientations or positional relationships indicated by terms such as "circumferential," "axial," "radial," "tangential," "width," etc. are based on the orientations or positional relationships shown in the drawings, and are intended merely to facilitate and simplify the description of this application, and are not to be understood as limitations on this application, as they do not indicate or imply that the devices or elements shown must have a particular orientation, be configured, or be operated in a particular orientation.

[0020] In the description of this application, when "first" or "second" is mentioned, it is merely for the purpose of distinguishing technical features, and should not be understood as indicating or implying the relative importance, or implying the number of the indicated technical features, or implying the context of the indicated technical features.

[0021] In the description of this application, terms such as installation, mounting, connection, etc. should be understood in a broad sense, and a person skilled in the art can reasonably determine the specific meaning of the above terms in this application by referring to the specific content of the technical solution.

[0022] The technical solutions of the present application will be described clearly and completely below with reference to the drawings. It is obvious that the embodiments described below are only some of the embodiments of the present application, but not all of the embodiments.

[0023] Referring to FIG. 1, a rotor 1000 according to an embodiment of the present application includes a rotor core 100, a first permanent magnet 200, and a second permanent magnet 300. The rotor core 100 is provided with an axial hole 111, which is used to mount a rotating shaft. The rotor core 100 is further provided with a plurality of first insertion grooves 130 and a plurality of second insertion grooves 140, which are alternately arranged along the circumferential direction of the rotor core 100. The number of first permanent magnets 200 matches the number of first insertion grooves 130, and the number of second permanent magnets 300 matches the number of second insertion grooves 140. In the embodiment shown in FIG. 1 , the number of the first permanent magnets 200 and the second permanent magnets 300 is four, and the number of the first insertion grooves 130 and the second insertion grooves 140 is four, where the first permanent magnets 200 fit into the first insertion grooves 130, and the four first permanent magnets 200 are mounted in one-to-one correspondence within the four first insertion grooves 130; the second permanent magnets 300 fit into the second insertion grooves 140, and the four second permanent magnets 300 are mounted in one-to-one correspondence within the four second insertion grooves 140.

[0024] Specifically, the first permanent magnets 200 and the second permanent magnets 300 are alternately distributed along the circumferential direction of the rotor core 100, one second permanent magnet 300 is provided between any two adjacent first permanent magnets 200, and the two first permanent magnets 200 are symmetrically arranged with respect to the second permanent magnet 300 between them, and one first permanent magnet 200 is provided between any two adjacent second permanent magnets 300, and the two second permanent magnets 300 are symmetrically arranged with respect to the first permanent magnet 200 between them, thus providing the rotor core 100 with two sets of permanent magnets, where the four first permanent magnets 200 may be understood as a first magnetic group, and the four second permanent magnets 300 may be understood as a second magnetic group. Both the first permanent magnets 200 and the second permanent magnets 300 penetrate the rotor core 100 along the axial direction of the rotor core 100.

[0025] Referring to FIG. 2, the magnetization direction of the first permanent magnet 200 is along the radial direction of the rotor core 100, and the magnetization direction of the second permanent magnet 300 is along the tangential direction of the rotor core 100, i.e., along the tangential direction of the rotor core 100. Specifically, the directions indicated by arrows in FIG. 2 are the magnetization directions of the first permanent magnet 200 and the second permanent magnet 300. The magnetization directions of adjacent first permanent magnets 200 are opposite, and the magnetization directions of adjacent second permanent magnets 300 are also opposite. That is, the magnetization directions of two adjacent second permanent magnets 300 are opposite. In one permanent magnet 200, the magnetization direction of one is along the clockwise tangential direction and the magnetization direction of the other is along the counterclockwise tangential direction, and in two adjacent second permanent magnets 300, if the magnetization direction of one is outward along the radial direction, the magnetization direction of the adjacent first permanent magnet 200 is inward along the radial direction, and in this way, two sets of permanent magnets with different magnetic field directions are formed in the rotor core 100, and the unipolar magnetic leakage of each permanent magnet can be reduced.

[0026] The first permanent magnet 200 and the second permanent magnet 300 employed in the embodiments of the present application are both made of ferrite, which has the advantages of excellent resistance to demagnetization and low cost, and are formed by magnetizing ferrite. Other weakly magnetic materials may also be used.

[0027] In the related art, considering that rotors using ferrite generally adopt a spoke structure to ensure that the air gap magnetic field strength of the motor reaches a certain amplitude value, the motor can output sufficient power, but in order to support the permanent magnets and ensure the physical strength of the rotor core, narrow support beams are generally installed between the permanent magnets inside the rotor, and the openings between the poles of the permanent magnets reduce magnetic leakage. The support beams are located between the holes and improve the physical strength of the rotor core, but the magnetic field lines generated by the permanent magnets will leak through the support beams, and some of the magnetic field lines will not reach the stator, resulting in a decrease in the utilization rate of the rotor magnetic field and a certain attenuation of the air gap magnetic field amplitude value.

[0028] Referring to FIG. 2, in the embodiment of the present application, the rotor core 100 uses the first insertion groove 130 and the second insertion groove 140 to regulate the positions of the first permanent magnet 200 and the second permanent magnet 300, respectively, eliminating the need to use a support beam structure to support the two sets of permanent magnets, and effectively reducing magnetic leakage.

[0029] Continuing to refer to FIG. 2 , in the embodiment of the present application, when a plane perpendicular to the magnetization direction of the second permanent magnet 300 is taken as the projection plane, the projections of this second permanent magnet 300 and the adjacent first permanent magnet 200 onto the projection plane partially overlap, and the adjacent first permanent magnet 200 and second permanent magnet 300 are installed close to each other. Taking the upper first permanent magnet 200 and second permanent magnet 300 shown in FIG. 2 as an example, the magnetization direction of the second permanent magnet 300 is along the clockwise tangential direction, and the tangential direction at this position coincides with the horizontal direction, that is, the projection plane is a plane perpendicular to the horizontal direction and is parallel to the axis of the rotor core 100, and in this way the projections of the first permanent magnet 200 and the second permanent magnet 300 onto this projection plane partially overlap.

[0030] In some embodiments, the sizes of the first permanent magnet 200 and the second permanent magnet 300 may be adjusted so that the projections of adjacent first permanent magnets 200 and second permanent magnets 300 on the projection plane completely overlap.

[0031] The rotor 1000 is used in a motor 3000, and the structure of the first permanent magnet 200 and the second permanent magnet 300 is optimized so that, when a plane perpendicular to the magnetization direction of the second permanent magnet 300 is taken as a projection plane, the projections of adjacent first permanent magnets 200 and second permanent magnets 300 on the projection plane partially or completely overlap. Referring to Figure 6, the first permanent magnets 200 are magnetized in the radial direction of the rotor core 100, and the second permanent magnets 300 are magnetized in the tangential direction of the rotor core 100. The magnetic field lines of the magnetic field of the first permanent magnets 200 extend in the radial direction of the rotor core 100, and the magnetization directions of two adjacent first permanent magnets 200 are opposite. Therefore, the magnetic field between adjacent first permanent magnets 200 forms a series magnetic path, and P1 in Figure 6 is one of the magnetic field lines in the series magnetic path. At the same time, the magnetic field lines of the second permanent magnet 300 curve from both ends of the second permanent magnet 300 toward the stator 2000, with the curvature direction being close to the radial direction of the rotor core 100. In this way, the magnetic field generated by the first permanent magnet 200 and the magnetic field generated by the second permanent magnet 300 form a parallel magnetic path. P1 and P2 in FIG. 6 are the two magnetic field lines in the parallel magnetic path. The magnetic path structure with both series and parallel connections effectively reduces magnetic leakage between adjacent poles and increases magnetic flux density, which helps improve the air gap magnetic flux density between the stator 2000 and rotor 1000 of the motor 3000. This increases the air gap magnetic field amplitude, reduces current at the same load, reduces line loss, suppresses harmonic magnetic fields, and reduces iron consumption, thereby improving the performance of the motor 3000.

[0032] 1 and 2, the cross section of the first permanent magnet 200 in the embodiment is rectangular, while the cross section of the second permanent magnet 300 may be polygonal instead of rectangular. By arranging the rectangular first permanent magnet 200 and the non-rectangular second permanent magnet 300, the arrangement between the first permanent magnet 200 and the second permanent magnet 300 can be made more compact, and when the rotor core 100 size is the same, the size of the two sets of permanent magnets can be effectively increased, resulting in a stronger fundamental air gap magnetic field. This is merely an example, and the number of first permanent magnets 200 and second permanent magnets 300 is not limited to four, but may be six, eight, or more, and is not specifically limited.

[0033] 2 and 3, the side extending along the width direction of the first permanent magnet 200 faces the second permanent magnet 300, i.e., the short side of the cross section of the first permanent magnet 200 is adjacent to the second permanent magnet 300, and an opposing surface 310 is provided at the end of the second permanent magnet 300 facing the first permanent magnet 200, and the opposing surface 310 is parallel to the opposing side surface of the first permanent magnet 200, making the arrangement of the first permanent magnet 200 and the second permanent magnet 300 more rational.

[0034] Specifically, the corners on both sides of the second permanent magnet 300 are processed by cutting or other methods, forming opposing surfaces 310 at the corners, and one end of the second permanent magnet 300 is made approximately trapezoidal. Compared to a method in which the corners are placed opposite the first permanent magnet 200, the second permanent magnet 300 in the embodiment of the present application is placed opposite the side of the first permanent magnet 200 via the opposing surfaces 310. This not only increases the size of the first permanent magnet 200 and the second permanent magnet 300 within a limited space, but also makes the distribution of the magnetic field lines between the first permanent magnet 200 and the second permanent magnet 300 more uniform, resulting in a better effect of the parallel magnetic path and a stronger fundamental air gap magnetic field.

[0035] Of course, this is merely an example, and the second permanent magnet 300 is not limited to the shape shown in FIG. 2 . For example, the cross-sectional shape of the second permanent magnet 300 may be approximately triangular, thereby allowing the side of the second permanent magnet 300 to be placed opposite the side of the first permanent magnet 200, making the arrangement more compact.

[0036] The magnetic induction strength exhibited after magnetization of the first permanent magnet 200 and the second permanent magnet 300 is called remanence and represents the maximum magnetic flux value that the magnets can provide. In the embodiment of the present application, the remanence range of the first permanent magnet 200 and the second permanent magnet 300 is 0.2 T (tesla) to 0.7 T, respectively. When this remanence range is satisfied, the magnetic field between adjacent first permanent magnets 200 can form a stable series magnetic path, and the magnetic field between the first permanent magnet 200 and the second permanent magnet 300 can form a stable parallel magnetic path, achieving the magnetic field distribution effect shown in Figure 6, effectively strengthening the fundamental air gap magnetic field, resulting in smaller current at the same load, reduced line loss, suppressed harmonic magnetic fields, reduced iron consumption, and improved efficiency and performance of the motor 3000.

[0037] The residual magnetism of the first permanent magnet 200 and the second permanent magnet 300 may be 0.2T, 0.4T, 0.5T, 0.7T, etc., and the residual magnetism of both may be the same or different values, and is not specifically limited.

[0038] 2 , in an embodiment of the present application, the sum of the cross-sectional area of ​​the first magnetic group and the cross-sectional area of ​​the second magnetic group is 50% or more of the cross-sectional area of ​​the rotor core 100. Here, the cross-sectional area of ​​the first magnetic group is the sum of the cross-sectional areas of all the first permanent magnets 200, and the cross-sectional area of ​​the second magnetic group is the sum of the cross-sectional areas of all the second permanent magnets 300. For example, the cross-sectional areas of the two sets of permanent magnets may account for 50%, 60%, or 70% or more of the cross-sectional area of ​​the rotor core 100. When the above condition is met, it can ensure a more reasonable distribution of the magnetic path topology structure of the first permanent magnets 200 and the second permanent magnets 300, which effectively increases the magnetic flux of the rotor 1000, reduces magnetic leakage, and effectively improves the air gap magnetic field.

[0039] Referring to Figures 1 and 2, the rotor core 100 includes an inner ring portion 110 and a plurality of outer core portions 120, which are arranged at intervals along the outer periphery of the inner ring portion 110. In the embodiment, there are four outer core portions 120, where a first insertion groove 130 is formed between the outer core portion 120 and the inner ring portion 110, and a second insertion groove 140 is formed between adjacent outer core portions 120, and the first insertion groove 130 and the second insertion groove 140 are arranged at an interval. The first permanent magnet 200 fits into the first insertion groove 130, with the outer peripheral wall of the first permanent magnet 200 tightly attached to the inner wall of the first insertion groove 130, and the second permanent magnet 300 fits into the second insertion groove 140, with the outer peripheral wall of the second permanent magnet 300 tightly attached to the inner wall of the second insertion groove 140. In this way, no gap is formed between the first insertion groove 130 and the second insertion groove 140, reducing the occurrence of magnetic leakage and strengthening the air gap magnetic field.

[0040] In the embodiment of the present application, an axial hole 111 is provided in the inner ring portion 110, and the inner ring portion 110 and the outer core portion 120 are formed by laminating punched sheets. The punched sheets may be silicon steel sheets or may be manufactured using other metal sheets with excellent magnetic conductivity, which has the advantage of low cost.

[0041] Referring to Figures 2 and 3, in some embodiments, a magnetic bridge 150 is provided between the inner ring portion 110 and the outer core portion 120, and the magnetic bridge 150 is located between the adjacent first insertion groove 130 and second insertion groove 140, that is, the outer core portion 120 and the inner ring portion 110 are connected via the magnetic bridge 150, thus making the rotor core 100 an integrated structure and improving the strength of the rotor core 100.

[0042] In some embodiments, the magnetic bridge 150 may be installed in a disconnected manner, i.e., there is no connection between the outer core portion 120 and the inner ring portion 110. The disconnected magnetic bridge 150 can reduce magnetic leakage between the poles and enhance the air gap magnetic field.

[0043] 2 and 3, protrusions 122 are provided on both ends of the outer peripheral edge of the outer core portion 120, and the protrusions 122 are installed to extend toward the second insertion groove 140, i.e., the protrusions 122 protrude from the ends of the outer core portion 120 along the circumferential direction of the rotor core 100. Recesses 320 are provided on both sides of the second permanent magnet 300, and when the second permanent magnet 300 is inserted into the second insertion groove 140, it abuts against the recesses 320 via the protrusions 122. The engagement between the protrusions 122 and the recesses 320 makes it possible to restrict the position of the second permanent magnet 300 along the radial direction of the rotor core 100, resulting in a stable and reliable structure. Because the second permanent magnet 300 is not rectangular, after the assembly of the second permanent magnet 300 is completed, its end protrudes beyond the outer periphery of the rotor core 100, realizing reverse saliency of the rotor 1000. The d-axis inductance is larger than the q-axis inductance, which reduces the high-frequency field-weakening current and reduces line loss.

[0044] Referring to FIG. 4, in some embodiments, the rotor 1000 further includes a connecting member and an end plate 400, where there are two end plates 400, each located at both ends of the rotor core 100 along its axial direction, and each outer core portion 120 is provided with a through hole 121 installed along the axial direction of the rotor core 100, and the connecting member passes through the through hole 121 to connect the end plates 400 at both ends. Here, the through hole 121 is located at the position of the symmetrical center line of the outer core part 120, and the connecting member may be a structure such as a stud or rivet. The end plate 400 is provided with a connecting hole 410 corresponding to the through hole 121. For example, the connecting member is a stud, and the connecting hole 410 is a screw hole. The stud passes through the through hole 121, and both ends of the stud are respectively connected to the screw holes of the end plate 400. In this way, the two end plates 400 can be locked and the rotor core 100 can be clamped, which serves to fix the inner ring part 110 and the outer core part 120 and improve the overall strength of the rotor core 100.

[0045] When the magnetic bridge 150 adopts a cut structure, there is no connection between the outer core portion 120 and the inner ring portion 110. Therefore, by adding the end plate 400 and connecting member structure of the above embodiment to the rotor 1000, the outer core portion 120 and the inner ring portion 110 can be positioned, which makes it more manufacturable and effectively improves the overall strength of the rotor 1000.

[0046] Referring to FIG. 3, the end face of the outer core portion 120 away from the inner annular portion 110 is an arcuate surface, and the center of the arcuate surface and the center of the inner annular portion 110 are not concentric. That is, the center of the arcuate surface at the edge of the rotor core 100 is offset from the center of the rotor core 100. By adjusting the eccentricity of the arcuate surface, it is possible to reduce harmonics such as the 5th, 7th, 13th, and 15th harmonics in the air gap magnetic flux density, thereby reducing the harmonic content.

[0047] 7 and 8, Figure 7 shows a comparison of the fast Fourier transform (FFT) results of the air-gap magnetic field between the conventional design and the present application. The conventional design is a rotor 1000 employing a spoke-type structure in the related art. As can be seen from the comparison, the amplitude of the fundamental harmonic is increased by approximately 25% or more compared to the original design, effectively reducing the operating current of the motor 3000 or improving the output power of the motor 3000, thereby increasing its power density. Furthermore, as can be seen from the FFT results, the amplitudes of the 7th, 17th, and 25th harmonics of the air-gap magnetic flux density are significantly reduced. Furthermore, by adopting the above-described structure, the embodiment of the present application not only strengthens the fundamental air-gap magnetic field of the motor 3000, but also appropriately widens the gap between the stator 2000 and rotor 1000 of the motor 3000 without adding residual magnetism from a permanent magnet, thereby improving the reliability of the motor 3000.

[0048] The series magnetic path in Figure 8 is the magnetic path formed in the rotor 1000 of the conventional design, while the mixed magnetic path is the magnetic path with both series and parallel in the embodiment of the present application. At a certain time, the distribution of the air gap magnetic field between the stator 2000 and the rotor 1000 becomes non-ideal sinusoidal, and each order of harmonics can be obtained by using Fourier decomposition. When the air gap magnetic flux density is stronger, the current of the motor 3000 becomes smaller at the same load, the line loss is lower, the heat density is reduced, and the motor 3000 can be designed smaller at the same temperature rise.

[0049] In a rotor according to an embodiment of the present application, a plurality of first permanent magnets and a plurality of second permanent magnets are alternately arranged along the circumferential direction of the rotor core. The first permanent magnets and the second permanent magnets are respectively magnetized. The magnetization direction of the first permanent magnets is along the radial direction of the rotor core, and the magnetization direction of the second permanent magnets is along the tangential direction of the rotor core, forming two sets of permanent magnets with different magnetic field directions in the rotor core. When a plane perpendicular to the magnetization direction of the second permanent magnets is taken as a projection plane, the projections of the second permanent magnets and the adjacent first permanent magnets on the projection plane partially or completely overlap each other. In this way, a series magnetic path can be formed between the adjacent first permanent magnets, and a parallel magnetic path can be formed between the first permanent magnets and the second permanent magnets. This reduces magnetic leakage between adjacent poles, increases magnetic flux density, and helps strengthen the fundamental air gap magnetic field of the motor, resulting in smaller current at the same load, lower line loss, suppression of harmonic magnetic fields, reduced iron consumption, and improved motor efficiency and performance.

[0050] 5, a motor 3000 according to an embodiment of the present application includes a stator 2000 and the rotor 1000 of the above embodiment, and the rotor 1000 is rotatably disposed within the stator 2000. The rotor core 100 has two sets of permanent magnets, the magnetization direction of the first permanent magnet 200 is along the radial direction of the rotor core 100, and the magnetization direction of the second permanent magnet 300 is along the tangential direction of the rotor core 100, and when a plane perpendicular to the magnetization direction of the second permanent magnet 300 is taken as a projection plane, the projection of the second permanent magnet 300 and the adjacent first permanent magnet 200 onto the projection plane partially or completely overlap. Referring to FIG. 6 , when the above conditions are met, the magnetic field between adjacent first permanent magnets 200 forms a series magnetic path, and the magnetic field between the first permanent magnet 200 and the second permanent magnet 300 forms a parallel magnetic path. This magnetic path structure with both series and parallel connections effectively reduces magnetic leakage between adjacent poles and increases magnetic flux density, which helps improve the air gap magnetic flux density between the stator 2000 and rotor 1000 of the motor 3000, increases the air gap magnetic field amplitude, reduces current at the same load, reduces line loss, suppresses harmonic magnetic fields, reduces iron consumption, and improves the efficiency and performance of the motor 3000.

[0051] By adopting the rotor 1000 and stator 2000 of the above embodiment, the inner diameter of the stator 2000 can be appropriately enlarged, and the air gap between the stator 2000 and the rotor 1000 can be increased, making it less likely that interference will occur between the stator 2000 and the rotor 1000 of the motor 3000, thereby reducing the risk of interference between the stator 2000 and the rotor 1000 and improving the reliability of the motor 3000.

[0052] The motor according to the embodiment of the present application applies the rotor of the above embodiment, and the rotor has two sets of permanent magnets, which can form a series magnetic path between adjacent first permanent magnets and a parallel magnetic path between the first and second permanent magnets, reducing magnetic leakage between adjacent poles and increasing magnetic flux density, which helps strengthen the fundamental air gap magnetic field of the motor, resulting in smaller current at the same load, reduced line loss, suppressed harmonic magnetic fields, reduced iron consumption, and improved motor efficiency and performance.In addition, the inner diameter of the motor stator can be appropriately enlarged to increase the air gap between the stator and rotor, making it less likely for interference to occur between the stator and rotor, thereby reducing the risk of stator-rotor interference and improving motor reliability.

[0053] The present invention also provides a compressor suitable for use in refrigeration appliances such as air conditioners and refrigerators. The compressor according to the present invention utilizes the motor of the above embodiment, and the motor rotor has two sets of permanent magnets, forming a series magnetic path between adjacent first permanent magnets and a parallel magnetic path between the first and second permanent magnets. This reduces magnetic leakage between adjacent poles, increases magnetic flux density, and strengthens the fundamental air-gap magnetic field of the motor, resulting in smaller current at the same load, reduced line losses, suppressed harmonic magnetic fields, reduced iron consumption, and improved compressor energy efficiency. The inner diameter of the motor stator may also be appropriately enlarged to increase the air gap between the stator and rotor, thereby reducing interference between the stator and rotor of the motor and reducing the risk of stator-rotor interference, thereby improving the overall reliability of the compressor.

[0054] Although several embodiments of the present application have been described in detail above with reference to the drawings, the present application is not limited to the above embodiments, and various modifications can be made within the scope of knowledge possessed by a person skilled in the art without departing from the spirit of the present application. [Explanation of symbols]

[0055] 100 rotor core 110 Inner Ring 111 Shaft hole 120 outer core 121 Through hole 122 Protrusion 130 First insertion groove 140 Second insertion groove 150 Magnetic Bridge 200 First Permanent Magnet 300 Second permanent magnet 310 Opposite Surface 320 recess 400 End Plate 410 Connection hole 1000 rotors 2000 stator 3000 motor.

Claims

1. a rotor core provided with a plurality of first insertion grooves and a plurality of second insertion grooves, the first insertion grooves and the second insertion grooves being alternately arranged along the circumferential direction of the rotor core; a plurality of first permanent magnets, the number of which corresponds to the number of the first insertion grooves, the first permanent magnets being attached to the corresponding first insertion grooves, and the magnetization direction of the first permanent magnets being along the radial direction of the rotor core; a rotor including: second permanent magnets, the number of which corresponds to the number of the second insertion grooves, the second permanent magnets being attached to corresponding ones of the second insertion grooves, the magnetization direction of the second permanent magnets being along the tangential direction of the rotor core, and when a plane perpendicular to the magnetization direction of the second permanent magnets is taken as a projection plane, the second permanent magnets and the adjacent first permanent magnets are projected onto the projection plane so as to at least partially overlap each other.

2. 2. The rotor according to claim 1, wherein a cross section of the first permanent magnet is rectangular, and an opposing surface is provided at an end of the second permanent magnet facing the first permanent magnet, the opposing surface being parallel to opposing side surfaces of the first permanent magnet.

3. 3. The rotor according to claim 1, wherein the range of remanence of the first permanent magnet and the second permanent magnet is 0.2T to 0.7T.

4. The rotor according to any one of claims 1 to 3, wherein the sum of the cross-sectional areas of the plurality of first permanent magnets and the plurality of second permanent magnets is 50% or more of the cross-sectional area of ​​the rotor core.

5. The rotor core according to any one of claims 1 to 4, wherein the rotor core includes an inner ring portion and a plurality of outer core portions, the plurality of outer core portions being arranged at intervals along the outer periphery of the inner ring portion, the first insertion groove being formed between the outer core portion and the inner ring portion, and the second insertion groove being formed between adjacent outer core portions.

6. 6. The rotor of claim 5, wherein a magnetic bridge is provided between the adjacent first insertion groove and the adjacent second insertion groove, and the outer core portion and the inner ring portion are connected via the magnetic bridge, or the magnetic bridge is installed by cutting.

7. 7. The rotor according to claim 5 or 6, wherein the rotor further includes a connecting member and end plates located at both ends of the rotor core, the outer core portion being provided with a through hole installed along the axial direction of the rotor core, and the connecting member passing through the through hole to connect the end plates at both ends.

8. A rotor as described in any one of claims 5 to 7, wherein protrusions extending toward the second insertion groove are provided on both ends of the outer core portion, and recesses are provided on both sides of the second permanent magnet, and the protrusions and recesses fit together to regulate the position of the second permanent magnet along the radial direction of the rotor core.

9. A rotor according to any one of claims 5 to 8, wherein an end face of the outer core portion away from the inner annular portion is an arcuate surface, and the center of the arcuate surface and the center of the inner annular portion are arranged non-concentrically.

10. A motor comprising a stator and the rotor according to any one of claims 1 to 9, wherein the rotor is rotatably provided within the stator.

11. A compressor comprising the motor of claim 10.

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