Rotor structure of an electric machine, electric machine and vehicle

Abstract

The application discloses a rotor structure of a motor, the motor and a vehicle, and relates to the technical field of motors.The rotor structure comprises a rotor core, a plurality of first permanent magnets and a plurality of second permanent magnets.The rotor core is provided with a plurality of mounting grooves.The first permanent magnets are radial magnetization permanent magnets, and the second permanent magnets are tangential magnetization permanent magnets.The plurality of first permanent magnets and the plurality of second permanent magnets are arranged alternately along the circumference of the rotor core.The magnetization directions of two adjacent first permanent magnets are opposite, and the magnetization directions of two adjacent second permanent magnets are opposite.At least one of the first permanent magnets and the second permanent magnets comprises a plurality of permanent magnet segments arranged along the radial direction of the rotor core.The rotor structure of the motor according to the embodiment of the application can reduce magnetic leakage, play a role in magnet focusing, reduce eddy current loss, reduce the cogging torque of the motor, reduce the torque fluctuation of the motor, improve the NVH performance of the motor, improve the control accuracy of the motor, and make full use of the performance of the permanent magnets.

Description

Technical Field

[0001] This invention relates to the field of electric motor technology, and more specifically, to a rotor structure for an electric motor, an electric motor, and a vehicle. Background Technology

[0002] In related technologies, the rotor structure of motors is greatly affected by eddy current losses, especially when used in high-speed permanent magnet synchronous motors for new energy vehicles with small radial dimensions. Eddy current losses are significant and cannot meet the high-efficiency energy conversion requirements of high-speed drive motors for new energy vehicles. To achieve the same torque and output power, more battery capacity or larger battery capacitors are required, resulting in higher costs. Summary of the Invention

[0003] The present invention aims to at least solve one of the technical problems existing in the prior art. To this end, one object of the present invention is to provide a rotor structure for an electric motor that reduces eddy current losses.

[0004] The present invention also proposes an electric motor having the above-described rotor structure.

[0005] The present invention also proposes a vehicle having the above-mentioned motor.

[0006] According to an embodiment of the present invention, a rotor structure of an electric motor includes: a rotor core having a plurality of mounting slots; a plurality of first permanent magnets and a plurality of second permanent magnets, each of the first permanent magnets being mounted in one of the mounting slots and being radially magnetized, and each of the second permanent magnets being mounted in one of the mounting slots and being tangentially magnetized; the plurality of first permanent magnets and the plurality of second permanent magnets being arranged alternately along the circumference of the rotor core, the magnetization directions of two adjacent first permanent magnets being opposite, and the magnetization directions of two adjacent second permanent magnets being opposite; at least one of the first permanent magnets and the second permanent magnets includes multiple permanent magnet segments arranged radially along the rotor core.

[0007] According to the rotor structure of the motor according to an embodiment of the present invention, a first permanent magnet with radial magnetization cooperates with a second permanent magnet with tangential magnetization, and at least one of the first permanent magnet and the second permanent magnet is divided into multiple permanent magnet segments. This can reduce magnetic leakage, play a magnetic focusing role, reduce eddy current loss, reduce cogging torque of the motor, reduce motor torque fluctuation, improve the NVH performance of the motor, improve the control accuracy of the motor, and make full use of the performance of permanent magnets.

[0008] In addition, the rotor structure of the motor according to the above embodiments of the present invention may also have the following additional technical features:

[0009] According to some embodiments of the present invention, among the multiple permanent magnet segments in the same mounting groove, the remanence of the innermost permanent magnet segment is less than that of the other permanent magnet segments.

[0010] According to some embodiments of the present invention, the residual magnetism of the plurality of permanent magnet segments in the same mounting slot increases radially outward along the rotor core.

[0011] According to some embodiments of the present invention, in a cross section perpendicular to the axial direction of the rotor structure, the area of ​​the innermost permanent magnet segment among the multiple permanent magnet segments in the same mounting groove is greater than the area of ​​the other permanent magnet segments.

[0012] According to some embodiments of the present invention, the width of the first permanent magnet along the radial direction of the rotor core is W1, and the plurality of mounting slots include a first mounting slot for mounting the first permanent magnet and a second mounting slot for mounting the second permanent magnet provided on the rotor core. The distance between the outermost edge of the first mounting slot and the outer peripheral surface of the rotor core is L1, and the distance between the outermost edge of the second mounting slot and the outer peripheral surface of the rotor core is L2, and satisfies:

[0013] According to some embodiments of the present invention, the central angle corresponding to the radial inner end face of the outermost permanent magnet segment of the first permanent magnet is 2α2, and the line connecting the circumferential end of the radial inner end face of the outermost permanent magnet segment of the second permanent magnet with the center point of the rotor core is a first line segment. The angle between the first line segment and the d-axis of the same magnetic pole is α1, and satisfies:

[0014] According to some embodiments of the present invention, the width of the first permanent magnet along the radial direction of the rotor core is W1, and the width of the second permanent magnet along the radial direction of the rotor core is W2, and satisfies:

[0015] According to some embodiments of the present invention, the first centerline of the first permanent magnet coincides with the d-axis, and the second permanent magnet has a second centerline extending radially along the rotor core, wherein the angle between the first centerline and the second centerline is 5° to 70°.

[0016] According to some embodiments of the present invention, the first center line of the first permanent magnet coincides with the d-axis, the second permanent magnet has a second center line extending radially along the rotor core, the distance between the center point of the second permanent magnet and the first center line is 2mm to 8mm in the direction perpendicular to the d-axis, and the distance between the center point of the first permanent magnet and the second center line is 2mm to 8mm in the direction perpendicular to the second center line.

[0017] According to some embodiments of the present invention, the rotor core is provided with a first mounting slot for mounting the first permanent magnet, a second mounting slot for mounting the second permanent magnet, and an air slot communicating with the radial inner end of the second mounting slot. The edges of the first mounting slot and the air slot that are close to each other are parallel to each other, and the distance between them is less than or equal to 0.2 mm.

[0018] The motor according to an embodiment of the present invention includes a rotor structure according to an embodiment of the present invention.

[0019] The vehicle according to an embodiment of the present invention includes a motor according to an embodiment of the present invention.

[0020] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0021] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0022] Figure 1 This is an axial view of the rotor structure according to the first embodiment of the present invention;

[0023] Figure 2 yes Figure 1 A magnified schematic diagram of one of the magnetic poles;

[0024] Figure 3 yes Figure 1 A partially enlarged structural diagram;

[0025] Figure 4 This is a partially enlarged schematic diagram of the rotor structure according to the second embodiment of the present invention;

[0026] Figure 5 This is a partially enlarged structural schematic diagram of the rotor structure according to the third embodiment of the present invention;

[0027] Figure 6 This is a partially enlarged schematic diagram of the rotor structure according to the fourth embodiment of the present invention;

[0028] Figure 7 This is a partially enlarged schematic diagram of the rotor structure according to the fifth embodiment of the present invention;

[0029] Figure 8 This is a radial view of the rotor core according to an embodiment of the present invention;

[0030] Figure 9 This is a schematic diagram of a motor according to an embodiment of the present invention;

[0031] Figure 10This is a schematic diagram of a vehicle according to an embodiment of the present invention.

[0032] Figure label:

[0033] Rotor structure 100; Motor 1000; Vehicle 2000;

[0034] Rotor core 10; First centerline 101; Second centerline 102; First mounting slot 11; Second mounting slot 12; Air slot 13; Silicon steel sheet 15;

[0035] First permanent magnet 21; Second permanent magnet 22; Rare earth permanent magnet segment 23; Ferrite segment 24. Detailed Implementation

[0036] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0037] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0038] In the description of this invention, "first feature" and "second feature" may include one or more of the features, "multiple" means two or more, "above" or "below" the second feature may include the first and second features being in direct contact, or the first and second features being in contact through another feature between them, and "above," "over," and "on top" the second feature may include the first feature being directly above or diagonally above the second feature, or simply indicate that the first feature is at a higher horizontal level than the second feature.

[0039] The rotor structure 100 of the motor 1000, the motor 1000 having the rotor structure 1000, and the vehicle 2000 having the motor 1000 described below are described with reference to the accompanying drawings according to embodiments of the present invention.

[0040] Reference Figures 1-7As shown, the rotor structure 100 of the motor 1000 according to an embodiment of the present invention may include: a rotor core 10, a plurality of first permanent magnets 21 and a plurality of second permanent magnets 22.

[0041] Specifically, the multiple first permanent magnets 21 are of the same size, and the multiple second permanent magnets 22 are of the same size. Both the first permanent magnets 21 and the second permanent magnets 22 are mounted on the rotor core 10. That is, the rotor core 10 has multiple mounting slots, with each first permanent magnet 21 mounted in one mounting slot and each second permanent magnet 22 mounted in one mounting slot. Furthermore, the multiple first permanent magnets 21 and the multiple second permanent magnets 22 are arranged alternately along the circumference of the rotor core 10. In other words, on the circumference of the rotor core 10, a second permanent magnet 22 is positioned between any two adjacent first permanent magnets 21, and a first permanent magnet 21 is positioned between any two adjacent second permanent magnets 22.

[0042] Among them, the first permanent magnet 21 is a radially magnetized permanent magnet, the second permanent magnet 22 is a tangentially magnetized permanent magnet, the magnetization directions of two adjacent first permanent magnets 21 are opposite, and the magnetization directions of two adjacent second permanent magnets 22 are opposite.

[0043] Specifically, such as Figure 1 and Figure 2 As shown, one of the first permanent magnets 21 has an N pole at its outer end and an S pole at its inner end along the radial direction of the rotor core 10. In the circumferential direction of the rotor core 10, the other first permanent magnet 21 adjacent to the first permanent magnet 21 has an S pole at its outer end and an N pole at its inner end along the radial direction of the rotor core 10. Among the two second permanent magnets 22 located on both sides of the first permanent magnet 21, in the circumferential direction of the rotor core 10, the sides of the two second permanent magnets 22 facing each other have N poles and the sides facing away from each other have S poles. Among the two second permanent magnets 22 located on both sides of the other first permanent magnet 21, in the circumferential direction of the rotor core 10, the sides of the two second permanent magnets 22 facing each other have S poles and the sides facing away from each other have N poles.

[0044] Therefore, the aforementioned first permanent magnet 21, half of a second permanent magnet 22 located on one side of it, and half of a second permanent magnet 22 located on the other side of it constitute one N pole of the motor 1000; the aforementioned other first permanent magnet 21, half of a second permanent magnet 22 located on one side of it, and half of a second permanent magnet 22 located on the other side of it constitute one S pole of the motor 1000. The rotor structure 100 forms an asymmetrical N / S pole, which differs from the magnetic field distribution of a traditional symmetrical N / S pole motor, thus improving the magnetic concentration capability of the motor 1000 and reducing magnetic leakage.

[0045] It should be noted that the number of the first permanent magnet 21 and the second permanent magnet 22 can be even, and the quantity can be set according to the actual situation, including but not limited to... Figure 1 The eight first permanent magnets 21 and eight second permanent magnets 22 shown in the figure may, in other embodiments, have four, six or ten first permanent magnets 21 and second permanent magnets 22, etc.

[0046] In addition, such as Figures 2-7 As shown, at least one of the first permanent magnet 21 and the second permanent magnet 22 includes multiple permanent magnet segments arranged radially along the rotor core 10. Each permanent magnet segment has an N pole and a S pole, and the magnetization directions of segments belonging to the same permanent magnet are the same.

[0047] For example Figure 2 and Figure 3 For example, the first permanent magnet 21 includes two permanent magnet segments arranged radially along the rotor core 10; the second permanent magnet 22 includes two permanent magnet segments arranged radially along the rotor core 10. Figure 4 For example, the first permanent magnet 21 includes three permanent magnet segments, which are arranged radially along the rotor core 10; the second permanent magnet 22 includes three permanent magnet segments, which are arranged radially along the rotor core 10.

[0048] In some embodiments, adjacent permanent magnet segments can be connected by means of glue or welding to improve the performance of motor 1000.

[0049] By segmenting the permanent magnets (at least one of the first permanent magnet 21 and the second permanent magnet 22), the cogging torque and torque fluctuation are reduced, thus improving the NVH performance of the motor 1000. Furthermore, the eddy current losses caused by the segmentation are reduced because each permanent magnet segment is thinner, and the equivalent area and equivalent magnetic reluctance of the permanent magnets are increased, indirectly reducing eddy current losses and improving the efficiency of the motor 1000. Under the same conditions, a wider speed range and more efficient energy utilization can be achieved with a lower battery capacity or a lower number of battery packs, thereby reducing power density costs and making the motor 1000 more competitive.

[0050] According to an embodiment of the present invention, the rotor structure 100 of the motor 1000 uses a radially magnetized first permanent magnet 21 and a tangentially magnetized second permanent magnet 22 to cooperate. At least one of the first permanent magnet 21 and the second permanent magnet 22 is divided into multiple permanent magnet segments, which can reduce magnetic leakage, play a magnetic focusing role, reduce eddy current loss, reduce the cogging torque of the motor 1000, reduce the torque fluctuation of the motor 1000, improve the NVH performance of the motor 1000, improve the control accuracy of the motor 1000, and make full use of the performance of the permanent magnet.

[0051] In some embodiments, the first permanent magnet 21 and the second permanent magnet 22 have the same dimensions along the axial direction of the rotor structure 100, which can reduce magnetic leakage.

[0052] According to some embodiments of the present invention, among multiple permanent magnet segments in the same mounting groove, the remanence of the innermost permanent magnet segment is less than that of the other permanent magnet segments. Taking the innermost and outermost permanent magnet segments as examples, the outermost and innermost permanent magnet segments can be neodymium iron boron and ferrite; or AlNiCo and ferrite; or sucrose cobalt and ferrite; or sucrose cobalt and neodymium iron boron; or sucrose cobalt and AlNiCo; or the same type of magnet with a higher grade and a lower grade, etc. In some specific embodiments, the outermost permanent magnet segment can be a rare earth permanent magnet segment 23, and the innermost permanent magnet segment can be a ferrite segment 24.

[0053] Materials with high remanence can achieve high torque requirements and a high AC inductance component Lq, thus enabling a wider speed control range. However, high remanence tends to lead to higher costs, while materials with low remanence can reduce costs. Furthermore, by using them in the innermost permanent magnet section, i.e., positioned away from the stator-rotor contact surface, excessive stress on the motor rotor caused by centrifugal force during high-speed operation can be avoided, preventing damage to the motor. They also provide good anti-demagnetization effects.

[0054] Specifically, rare-earth permanent magnets have high magnetic flux density and stable demagnetizing properties. Using rare-earth permanent magnets can increase the saliency ratio of motor 1000 (ρ=Lq / Ld) by increasing Lq. The electromagnetic torque formula is Tem=p*(Ψf*Iq+(Ld-Lq)*Id*Iq), and the reluctance torque is: p*(Ld-Lq)*Id*Iq. Therefore, using rare-earth permanent magnet materials can increase the reluctance torque of motor 1000 and achieve a wider speed control range. Utilizing the high magnetic flux density of rare-earth permanent magnets, the flux density is enhanced, the utilization rate of permanent magnets is improved, the magnetic load Ψf is increased, and the permanent magnet torque (p*Ψf*Iq) is increased. Ferrite performance can reach one-third that of rare-earth permanent magnets, and the raw material cost is low. Increasing the amount of ferrite can ensure the performance of motor 1000. Simultaneously, placing it away from the stator-rotor contact surface avoids the risk of permanent magnet damage during high-speed operation of motor 1000, reducing the repair cost of motor 1000.

[0055] Therefore, using a combination of materials with high remanence and low remanence, such as rare earth permanent magnets and ferrites, can avoid the problem of excessively high costs when using only rare earth permanent magnets, and also avoid the problem of insufficient magnetic flux density and inability to achieve a large speed control range when using only ferrites. At the same time, it can reduce the amount of rare earth permanent magnets used, reduce the cost of motor 1000, and increase profits.

[0056] In some embodiments, among the multiple permanent magnet segments within the same mounting slot, the remanence of the multiple permanent magnet segments increases radially outward along the rotor core 10 to further reduce raw material costs, decrease the risk of demagnetization of the motor 1000, and avoid rotor swivel. Taking the first permanent magnet 21 comprising three permanent magnet segments as an example, the remanence of the outermost permanent magnet segment is greater than that of the middle permanent magnet segment, and the remanence of the middle permanent magnet segment is greater than that of the innermost permanent magnet segment. For example, the outermost permanent magnet segment, the middle permanent magnet segment, and the innermost permanent magnet segment can be NdFeB, neodymium iron boron, and ferrite, respectively; or NdFeB, AlNiCo, and ferrite, etc.

[0057] In the embodiments of the present invention, the number of segments of the first permanent magnet 21 and the second permanent magnet 22 and the size of each segment can be flexibly set according to the actual situation.

[0058] In some embodiments, the number of segments can be two or three to avoid the permanent magnet segments from cracking during processing, which would affect production costs.

[0059] In some embodiments, such as Figures 2-7 As shown, on a cross section perpendicular to the axial direction of the rotor structure 100, the area of ​​the innermost permanent magnet segment is larger than that of the other permanent magnet segments, so that the volume and weight of the innermost permanent magnet segment are both greater than those of the other permanent magnet segments. The multiple permanent magnet segments form a non-uniform segmented mixed material structure, which can reduce cogging torque, thereby reducing the torque fluctuation of the motor 1000, reducing the vibration of the motor 1000, and improving NVH performance.

[0060] For example, in such Figures 2-3 In the example shown, the cross-sections of multiple permanent magnet segments are rectangular, and the dimensions of multiple rectangles along the tangent of the rotor core 10 are equal. The radial dimension of the innermost permanent magnet segment along the rotor core 10 is greater than the radial dimension of the other permanent magnet segments along the rotor core 10, so that the cross-sectional area of ​​the innermost permanent magnet segment is greater than the cross-sectional area of ​​the other permanent magnet segments.

[0061] The outer permanent magnet section meets the high magnetic flux density requirements of the high-speed motor 1000. Its smaller size also reduces the centrifugal force exerted by the permanent magnets on the rotor structure 100 during rotation, preventing rotor swirl during high-speed rotation. Furthermore, the smaller size and larger residual magnet of the permanent magnet section reduce the cost of permanent magnet raw materials for the rotor structure 100, while the segmented arrangement of the permanent magnets reduces eddy current losses and improves the efficiency of the motor 1000.

[0062] Furthermore, the innermost permanent magnet section also provides demagnetization resistance, preventing excessive mechanical stress on the mounting slot caused by the permanent magnet during high-speed operation of the motor 1000, which could lead to wear or impact on the rotor structure 100, and also avoiding stator rubbing. Therefore, the size of the outer permanent magnet can be appropriately reduced, which can reduce the amount of permanent magnets with large residual magnetism and lower costs.

[0063] The innermost permanent magnet section increases the demagnetization resistance of motor 1000. This prevents demagnetization of the permanent magnets when the motor 1000 is running at high speed and heat dissipation is insufficient within a certain temperature range, thus protecting the motor 1000 and avoiding the maintenance costs of replacing damaged permanent magnets. It also reduces the maintenance costs associated with replacing the permanent magnets in rotor structure 100. Because the permanent magnets with low residual magnetism are positioned far from the stator-rotor contact surface, the centrifugal force exerted on rotor structure 100 by the permanent magnets is less significant during high-speed operation of motor 1000. Therefore, the size of the innermost permanent magnet section can be appropriately increased, thereby enhancing the demagnetization resistance of motor 1000.

[0064] In some specific embodiments, such as Figure 2 and Figure 3 As shown, both the first permanent magnet 21 and the second permanent magnet 22 comprise two segments arranged radially along the rotor core 10. The first permanent magnet 21 consists of an outer rare-earth permanent magnet segment 23 and an inner ferrite segment 24, and the second permanent magnet 22 also consists of an outer rare-earth permanent magnet segment 23 and an inner ferrite segment 24. This design ensures a 1000 MHz magnetic flux density in the motor, increases reluctance torque, reduces the cost of permanent magnet raw materials, decreases eddy current losses, and improves the motor's 1000 MHz efficiency.

[0065] In addition, continue to refer to Figure 2 and Figure 3 As shown, the extension length of the rare earth permanent magnet segment 23 is less than that of the ferrite segment 24, which can further reduce the amount of rare earth permanent magnets used, reduce the cost of permanent magnet raw materials, reduce eddy current losses, and help reduce the impact of the centrifugal force of the permanent magnet on the rotor structure 100 when the motor 1000 is running at high speed, thus avoiding rotor swiping.

[0066] According to some embodiments of the present invention, such as Figures 2-4 As shown, the rotor core 10 has a first mounting slot 11 and a second mounting slot 12. The first mounting slot 11 is used to mount a first permanent magnet 21, and the second mounting slot 12 is used to mount a second permanent magnet 22. The distance between the outermost edge of the first mounting slot 11 and the outer circumferential surface of the rotor core 10 is L1, and the distance between the outermost edge of the second mounting slot 12 and the outer circumferential surface of the rotor core 10 is L2. The width of the first permanent magnet 21 along the radial direction of the rotor core 10 is W1, that is, the sum of the widths of all permanent magnet segments included in the first permanent magnet 21 is W1. L1, L2, and W1 satisfy:

[0067] Due to the size limitations of L1 and L2, the demagnetization resistance deteriorates when the first permanent magnet 21 and the second permanent magnet 22 move inward toward the center of the rotor core 10. Due to the size limitations of W1, as W1 increases, the distance between the first permanent magnet 21 and the adjacent second permanent magnet 22 increases; as W1 decreases, the distance between them decreases. This change in magnetic reluctance alters the distribution and direction of the magnetic field lines, thus reducing the demagnetization resistance. However, when the above parameter relationships are satisfied, an excellent demagnetization resistance can be achieved.

[0068] According to some embodiments of the present invention, such as Figures 2-4 As shown, the central angle corresponding to the radial inner end face of the outermost permanent magnet segment of the first permanent magnet 21 is 2α2. The line connecting the circumferential end of the radial inner end face of the outermost permanent magnet segment of the second permanent magnet 22 with the center point of the rotor core 10 is the first line segment, and the angle between the first line segment and the d-axis of the same magnetic pole is α1.

[0069] Specifically, in a cross-section perpendicular to the axis of the rotor structure 100, the first permanent magnet 21 has a first centerline 101 coinciding with the d-axis. A second line segment is formed by connecting the endpoint of the radially inner end face of the outermost permanent magnet segment of the first permanent magnet 21 to the center point of the rotor core 10, and the angle between the second line segment and the first centerline 101 is α2. Similarly, a first line segment is formed by connecting the endpoint of the radially inner end face of the outermost permanent magnet segment of the second permanent magnet 22 near the endpoint of the first permanent magnet 21 to the center point of the rotor core 10.

[0070] Where W1, α1, and α2 satisfy:

[0071] Due to the limited angular ranges of α1 and α2, changes in α1 and α2 alter the distance between the first permanent magnet 21 and the second mounting slot 12, resulting in a deterioration in the anti-magnetic leakage effect. The numerical ranges of L1, L2, W1, α1, and α2 are mutually restrictive; if a structure exceeding these ranges is used, the anti-magnetic leakage effect weakens.

[0072] According to some embodiments of the present invention, such as Figure 2 and Figure 3 As shown, the width of the first permanent magnet 21 along the radial direction of the rotor core 10 is W1, and the width of the second permanent magnet 22 along the radial direction of the rotor core 10 is W2, and W1 and W2 satisfy: Within the above-mentioned ratio range, the effect of reducing magnetic leakage is better. For example, It can be 0.2, 0.5, 1, and 1.5, etc.

[0073] According to some embodiments of the present invention, such as Figure 2 and Figure 3As shown, the first centerline 101 of the first permanent magnet 21 coincides with the d-axis, and the second permanent magnet 22 has a second centerline 102 extending radially along the rotor core 10, with the included angle between the first centerline 101 and the second centerline 102 being 5° to 70°. Within the above range, the volumes of the first permanent magnet 21 and the second permanent magnet 22 can be sufficiently large to ensure the magnetic performance of the motor 1000, and the processing difficulty of structures such as mounting slots is relatively low, resulting in better reduction of magnetic leakage and demagnetization resistance.

[0074] In some embodiments, such as Figure 2 and Figure 3 As shown, the first centerline 101 of the first permanent magnet 21 coincides with the d-axis. In the direction perpendicular to the d-axis, the distance L3 between the center point of the second permanent magnet 22 and the first centerline 101 is 2mm to 8mm. In some embodiments, the second permanent magnet 22 has a second centerline 102 extending radially along the rotor core 10. In the direction perpendicular to the second centerline 102, the distance L4 between the center point of the first permanent magnet 21 and the second centerline 102 is 2mm to 8mm. This approach is beneficial for increasing the amount of permanent magnets used in the first permanent magnet 21 and the second permanent magnet 22 to improve magnetic performance, and it also allows for a more rational structural arrangement to reduce magnetic leakage.

[0075] In some embodiments where the rotor core 10 is provided with a first mounting groove 11 and a second mounting groove 12, such as... Figures 2-7 As shown, the rotor core 10 may also be provided with an air groove 13, which communicates with the radial inner end of the second mounting groove 12. The edges of the first mounting groove 11 and the air groove 13 are parallel to each other, and the distance L5 between the parallel portions is less than or equal to 0.2 mm. For example, in some specific embodiments, the distance between the parallel portions can be 0.1 mm. This forms a magnetic isolation structure between the first mounting groove 11 and the air groove 13, which improves the distribution of magnetic lines of force, enhances the magnetic concentration effect, and reduces magnetic leakage.

[0076] It should be noted that, as Figures 3-7 As shown, the structure of the air trough 13 can be flexibly configured according to actual conditions, wherein, with Figure 5 Compared to the embodiments shown, Figure 3 In the embodiment shown, the outer surface of the air groove 13 is arc-shaped, and the end of the second permanent magnet 22 extends into the air groove 13, which can improve the distribution of magnetic lines of force, thereby increasing the utilization rate of the permanent magnet and reducing magnetic waste.

[0077] According to some embodiments of the present invention, such as Figure 8 As shown, the rotor core 10 includes a plurality of silicon steel sheets 15, which are stacked axially. A first permanent magnet 21 and a second permanent magnet 22 are inserted into the stacked silicon steel sheets 15, and the silicon steel sheets 15 constitute part of the rotor magnetic circuit.

[0078] like Figure 9 As shown, the motor 1000 according to an embodiment of the present invention includes a rotor structure 100 according to an embodiment of the present invention. Since the rotor structure 100 of the motor 1000 according to an embodiment of the present invention has the aforementioned beneficial technical effects, the motor 1000 according to an embodiment of the present invention, by cooperating a radially magnetized first permanent magnet 21 and a tangentially magnetized second permanent magnet 22, and at least one of the first permanent magnet 21 and the second permanent magnet 22 being divided into multiple permanent magnet segments, can reduce magnetic leakage, achieve a magnetic focusing effect, and simultaneously reduce eddy current losses, reduce the cogging torque of the motor 1000, reduce torque fluctuation of the motor 1000, improve the NVH performance of the motor 1000, improve the control accuracy of the motor 1000, and fully utilize the performance of the permanent magnets.

[0079] like Figure 10 As shown, the vehicle 2000 according to an embodiment of the present invention includes a motor 1000 according to an embodiment of the present invention. Since the motor 1000 according to the embodiment of the present invention has the aforementioned beneficial technical effects, the vehicle 2000 according to the embodiment of the present invention, by cooperating with a radially magnetized first permanent magnet 21 and a tangentially magnetized second permanent magnet 22, and with at least one of the first permanent magnet 21 and the second permanent magnet 22 divided into multiple permanent magnet segments, can reduce magnetic leakage, achieve a magnetic focusing effect, reduce eddy current losses, reduce the cogging torque of the motor 1000, reduce torque fluctuation of the motor 1000, improve the NVH performance of the motor 1000, improve the control accuracy of the motor 1000, and fully utilize the performance of the permanent magnets.

[0080] Here, vehicle 2000 can be a new energy vehicle. In some embodiments, the new energy vehicle can be a pure electric vehicle with motor 1000 as the main driving force. In other embodiments, the new energy vehicle can also be a hybrid vehicle with both an internal combustion engine and motor 1000 as the main driving forces. Regarding the motor 1000 mentioned in the above embodiments that provides driving power for the new energy vehicle, the way to provide electrical energy to the motor 1000 can be a power battery, hydrogen fuel cell, etc., and no special limitation is made here. It should be noted that this is merely an exemplary description of the structure of new energy vehicles, etc., and is not intended to limit the scope of protection of this invention.

[0081] Other configurations and operations of the motor 1000 and vehicle 2000 according to embodiments of the present invention are known to those skilled in the art and will not be described in detail here.

[0082] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0083] In the description of this specification, the references to terms such as "embodiment," "specific embodiment," and "example" indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0084] Although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A rotor structure for an electric motor, characterized in that, include: The rotor core is provided with multiple mounting slots; Multiple first permanent magnets and multiple second permanent magnets are provided. Each first permanent magnet is installed in a mounting slot and is radially magnetized. Each second permanent magnet is installed in a mounting slot and is tangentially magnetized. The multiple first permanent magnets and multiple second permanent magnets are arranged alternately along the circumference of the rotor core. The magnetization directions of two adjacent first permanent magnets are opposite, and the magnetization directions of two adjacent second permanent magnets are opposite. At least one of the first permanent magnet and the second permanent magnet includes multiple permanent magnet segments arranged radially along the rotor core; The first permanent magnet has a radial width of W1 along the rotor core. The plurality of mounting slots include a first mounting slot for mounting the first permanent magnet and a second mounting slot for mounting the second permanent magnet on the rotor core. The distance between the outermost edge of the first mounting slot and the outer circumferential surface of the rotor core is L1, and the distance between the outermost edge of the second mounting slot and the outer circumferential surface of the rotor core is L2, and the following conditions are met: 。 2. The rotor structure of the motor according to claim 1, characterized in that, Among the multiple permanent magnet segments in the same mounting slot, the remanence of the innermost permanent magnet segment is less than that of the other permanent magnet segments.

3. The rotor structure of the motor according to claim 2, characterized in that, In the same mounting slot, the residual magnetism of the multiple permanent magnet segments increases radially outward along the rotor core.

4. The rotor structure of the motor according to claim 2, characterized in that, On a cross section perpendicular to the axial direction of the rotor structure, among the multiple permanent magnet segments in the same mounting groove, the area of ​​the innermost permanent magnet segment is larger than the area of ​​the other permanent magnet segments.

5. The rotor structure of the motor according to claim 1, characterized in that, The central angle corresponding to the radial inner end face of the outermost permanent magnet segment of the first permanent magnet is 2α2. The line connecting the circumferential end of the radial inner end face of the outermost permanent magnet segment of the second permanent magnet with the center point of the rotor core is the first line segment. The angle between the first line segment and the d-axis of the same magnetic pole is α1, and satisfies: 。 6. The rotor structure of the motor according to claim 1, characterized in that, The width of the first permanent magnet along the radial direction of the rotor core is W1, and the width of the second permanent magnet along the radial direction of the rotor core is W2, and the following conditions are met: 。 7. The rotor structure of the motor according to claim 1, characterized in that, The first centerline of the first permanent magnet coincides with the d-axis, and the second permanent magnet has a second centerline extending radially along the rotor core. The angle between the first centerline and the second centerline is 5° to 70°.

8. The rotor structure of the motor according to claim 1, characterized in that, The first permanent magnet has a first center line that coincides with the d-axis. The second permanent magnet has a second center line that extends radially along the rotor core. In the direction perpendicular to the d-axis, the distance between the center point of the second permanent magnet and the first center line is 2mm to 8mm. In the direction perpendicular to the second center line, the distance between the center point of the first permanent magnet and the second center line is 2mm to 8mm.

9. The rotor structure of the motor according to any one of claims 1-8, characterized in that, The rotor core is provided with a first mounting slot for mounting the first permanent magnet, a second mounting slot for mounting the second permanent magnet, and an air slot communicating with the radial inner end of the second mounting slot. The edges of the first mounting slot and the air slot are parallel to each other and the distance between them is less than or equal to 0.2 mm.

10. An electric motor, characterized in that, The rotor structure of the motor includes any one of claims 1-9.

11. A vehicle, characterized in that, Includes the motor according to claim 10.

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