Rotor punching sheet, rotor assembly, motor, driving assembly and vehicle

Abstract

The invention relates to a rotor punching sheet, a rotor assembly, a motor, a driving assembly and a vehicle, at least one magnetic slot structure is formed on the rotor punching sheet, each magnetic slot structure comprises a plurality of magnetic slot groups which are arranged at intervals along the radial direction of the rotor punching sheet, each magnetic slot group comprises at least one magnetic slot, a magnetic flux gap is formed between two adjacent magnetic slot groups, and the magnetic flux gap is communicated with the magnetic slot. The magnetic flux gaps comprise two first magnetic flux gaps and a second magnetic flux gap, and the second magnetic flux gap is connected between the two first magnetic flux gaps; wherein the magnetic slots of at least one magnetic slot group comprise arc-shaped structures, so that the width of the first magnetic flux gap is increased in the direction from the first magnetic flux gap to the second magnetic flux gap. The invention aims to solve the technical problems that the magnetic flux density of the rotor punching sheet is reduced and the magnetic resistance is increased due to magnetic flux density saturation of the rotor punching sheet in the prior art.

Description

Technical Field

[0001] The present application relates to the field of motor technology, and in particular to a rotor punching sheet, a rotor assembly, a motor, a drive assembly and a vehicle. Background Art

[0002] Permanent magnet motors are important power sources. In order to meet the needs of motors, the requirements for the motor's rotor assembly are high strength and high speed. The rotor assembly is formed by stacking multiple rotor sheets. In the prior art, the motor's rotor is formed by stacking multiple rotor cores, which leads to the problem of magnetic flux saturation in the rotor, which in turn leads to a decrease in the rotor's magnetic flux density and an increase in magnetic resistance. Summary of the invention

[0003] The present application provides a rotor punching, a rotor assembly, a motor, a drive assembly and a vehicle, and the present application aims to solve the technical problem in the prior art that the magnetic flux density of the rotor punching is reduced and the magnetic resistance is increased due to magnetic density saturation of the rotor punching.

[0004] In order to achieve the above object, according to a first aspect of the present application, a rotor punching is provided, wherein at least one magnetic slot structure is formed on the rotor punching, each of the magnetic slot structures comprises a plurality of magnetic slot groups spaced apart along the radial direction of the rotor punching, each of the magnetic slot groups comprises at least one magnetic slot, a magnetic flux gap is formed between two adjacent magnetic slot groups, the magnetic flux gap comprises two first magnetic flux gaps and a first magnetic flux gap, and the second magnetic flux gap is connected between the two first magnetic flux gaps;

[0005] Wherein, the magnetic slot of at least one of the magnetic slot groups comprises an arc-shaped structure, so that the width of the first magnetic flux gap increases in the direction from the first magnetic flux gap to the second magnetic flux gap.

[0006] Optionally, the material of the rotor punching sheet includes an amorphous alloy.

[0007] Optionally, the magnetic slots of each magnetic slot group include an arc-shaped structure.

[0008] Optionally, in the same magnetic slot group, the arc-shaped structures of a plurality of the magnetic slots have the same curvature.

[0009] Optionally, each of the magnetic slot groups has a first symmetry line extending in a radial direction of the rotor punching sheet, and the magnetic slots of each of the magnetic slot groups are symmetrically arranged along the first symmetry line.

[0010] Optionally, the first symmetry lines of the plurality of magnetic slot groups are arranged to overlap.

[0011] Optionally, the center of curvature of the arc-shaped structure is located on the outside or inside of the arc-shaped structure.

[0012] Optionally, the number of the magnetic slot structures of the rotor punching is n1, the number of the magnetic slots in each of the magnetic slot structures is n2, n1 and n2 are integers, and 0.5≤n1 / n2≤5.33.

[0013] Optionally, the two adjacent magnetic groove groups are a first sub-magnetic groove group and a second sub-magnetic groove group, the first sub-magnetic groove group is located outside the second sub-magnetic groove group, the curvature of the arc structure of the first sub-magnetic groove group is θ1, the curvature of the arc structure of the second sub-magnetic groove group is θ2, and 0.0625≤θ1 / θ2≤14.

[0014] Optionally, the rotor punching includes a plurality of fan-shaped regions, and the plurality of fan-shaped regions are connected along the circumferential end of the rotor punching, each of the fan-shaped regions is provided with a magnetic slot structure, and each of the magnetic slot structures includes at least one arc structure, the curvature of the fan-shaped region is α1, the curvature of the arc structure is α2, and 0.056≤α1 / α2≤2.

[0015] Optionally, it further comprises a plurality of magnetic isolation bridges, each of which has a width L, 0.5 mm ≤ L ≤ 4.5 mm.

[0016] Optionally, the two adjacent magnetic groove groups are respectively a first sub-magnetic groove group and a second sub-magnetic groove group, the first sub-magnetic groove group is located outside the second sub-magnetic groove group, the arc-shaped structure of the second sub-magnetic groove group has a side wall, the side wall is close to the first sub-magnetic groove group, the side wall includes two side portions opposite to each other in the extension direction of the side wall, wherein the minimum distance between the side wall and the magnetic groove of the first sub-magnetic groove group is w1, and the minimum distance between the virtual connecting line segment between the two side portions and the magnetic groove of the first sub-magnetic groove group is w2, and 1.03≤w1 / w2≤3.

[0017] Optionally, the two adjacent magnetic groove groups are a first sub-magnetic groove group and a second sub-magnetic groove group, the first sub-magnetic groove group is located outside the second sub-magnetic groove group, the radius of curvature of the arc structure of the first sub-magnetic groove group is located on the side of the first sub-magnetic groove group away from the second sub-magnetic groove group, and the radius of curvature of the arc structure of the second sub-magnetic groove group is located on the side of the second sub-magnetic groove group facing the first sub-magnetic groove group.

[0018] Optionally, the two adjacent magnetic groove groups are the first sub-magnetic groove group and the second sub-magnetic groove group, the first sub-magnetic groove group is located outside the second sub-magnetic groove group, the radius of curvature of the arc structure of the first sub-magnetic groove group is located on the side of the first sub-magnetic groove group facing the second sub-magnetic groove group, and the radius of curvature of the arc structure of the second sub-magnetic groove group is located on the side of the second sub-magnetic groove group facing the first sub-magnetic groove group.

[0019] Optionally, any three adjacent magnetic groove groups are respectively the first sub-magnetic groove group, the second sub-magnetic groove group and the third sub-magnetic groove group, the second sub-magnetic groove group is located between the first sub-magnetic groove group and the third sub-magnetic groove group, the radius of curvature of the arc structure of the first sub-magnetic groove group is located on the side of the first sub-magnetic groove group away from the second sub-magnetic groove group, the radius of curvature of the arc structure of the second sub-magnetic groove group is located on the side of the second sub-magnetic groove group facing the first sub-magnetic groove group, and the radius of curvature of the arc structure of the third sub-magnetic groove group is located on the side of the third sub-magnetic groove group facing the second sub-magnetic groove group.

[0020] According to a second aspect of the present application, a rotor assembly is provided, which is formed by stacking the above-mentioned rotor sheets.

[0021] According to a third aspect of the present application, there is provided an electric motor comprising the above-mentioned rotor assembly.

[0022] According to a fourth aspect of the present application, a drive assembly is provided, comprising the above-mentioned motor.

[0023] According to a fifth aspect of the present application, a vehicle is provided, comprising the above-mentioned drive assembly.

[0024] Beneficial effects of this application:

[0025] In the technical solution of the present application, a magnetic flux gap is provided between two adjacent magnetic slot groups, and the magnetic flux gap includes two first magnetic flux gaps and a second magnetic flux gap, and the second magnetic flux gap is connected between the two first magnetic flux gaps; the magnetic slots of at least one magnetic slot group include an arc structure, so that the width of the first magnetic flux gap increases in the direction from the first magnetic flux gap to the second magnetic flux gap; by reasonably designing the positions and shapes of multiple magnetic slots, the width of the first magnetic flux gap increases in the direction from the first magnetic flux gap to the second magnetic flux gap, which can reduce the magnetic density saturation of the rotor punchings, thereby increasing the magnetic flux density of the rotor punchings and reducing the magnetic resistance.

[0026] Other features and advantages of the present application will be described in detail in the subsequent detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application, and those skilled in the art can obtain other drawings based on these drawings without creative work.

[0028] In order to more completely understand the present application and its beneficial effects, the following description will be given in conjunction with the accompanying drawings, wherein the same figure numbers represent the same parts in the following description.

[0029] Figure 1 It is a structural schematic diagram of an embodiment of a rotor punching provided by the present application;

[0030] Figure 2 yes Figure 1 A schematic diagram of the structure of the middle rotor punching from another perspective;

[0031] Figure 3 yes Figure 1 A structural diagram of the middle rotor punching plate from another perspective;

[0032] Figure 4 The schematic diagram of the air gap magnetic flux density of the arc-shaped rotor punching;

[0033] Figure 5 The schematic diagram of the air gap magnetic flux density of the rotor lamination with a straight structure;

[0034] Figure 6 The magnetic flux density diagram of the rotor lamination with arc-shaped junction;

[0035] Figure 7 It is a schematic diagram of magnetic flux density of a rotor lamination with a straight structure;

[0036] Figure 8 It is the analytical model of the magnetic circuit of the motor;

[0037] Fig. 9 It is a schematic structural diagram of a rotor punching sheet according to a first embodiment of the present application;

[0038] Fig.10 is a schematic structural diagram of a rotor punching sheet according to a second embodiment of the present application;

[0039] Fig.11 is a schematic structural diagram of a rotor punching sheet according to a third embodiment of the present application;

[0040] Fig.12 is a schematic structural diagram of a rotor punching sheet according to a fourth embodiment of the present application;

[0041] Fig.13 is a schematic structural diagram of a rotor punching sheet according to a fifth embodiment of the present application;

[0042] Fig.14 is a schematic structural diagram of a rotor punching sheet according to a sixth embodiment of the present application;

[0043] Fig.15 It is a schematic diagram of the preparation process of magnetic steel;

[0044] Fig.16 It is a schematic structural diagram of another embodiment of the rotor punching provided in the present application.

[0045] Description of reference numerals:

[0046] 100. Rotor punching sheet; 10. Magnetic slot structure; 1. Magnetic slot group; 111. First magnetic flux gap; 121. Second magnetic flux gap; 21. First sub-magnetic slot group; 211. First sub-magnetic slot; 22. Second sub-magnetic slot group; 221. Side wall; 222. Side; 223. Second sub-magnetic slot; 23. Third sub-magnetic slot group; 231. Third sub-magnetic slot; 2. Magnetic slot; 20. Arc structure; 3. Fan-shaped area; 4. Magnetic isolation bridge. DETAILED DESCRIPTION

[0047] The technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present application.

[0048] Permanent magnet motors are important power sources. To meet the needs of motors, the requirements for the motor rotor assembly are high strength and high speed. The rotor assembly is formed by stacking multiple rotor sheets. In the prior art, some motors have more than one magnetic isolation bridge on the outside of the rotor sheet to reduce the probability of magnetic leakage of the rotor assembly, which causes the rotor assembly to break due to insufficient strength during high-speed operation of the motor. In order to meet the strength requirements, some motors use different types of rotor sheet stacks to form a rotor assembly. Such a setting is conducive to increasing the cross-axis magnetic resistance and reducing the cross-axis inductance, but the processing difficulty is high and the process route is complicated.

[0049] In view of this, the present application proposes a rotor punching sheet 100. Figures 1 to 14 This is a structural schematic diagram of an embodiment of a rotor punching sheet 100 provided in the present application. The rotor punching sheet 100 provided in the present application has high structural strength, a simple processing method, and a low probability of magnetic leakage. The rotor punching sheet 100 will be described in detail below in conjunction with the main drawings.

[0050] See also Figure 1 and Figure 2The present application provides a rotor punching 100, on which at least one magnetic slot structure 10 is formed, each magnetic slot structure 10 includes a plurality of magnetic slot groups 1 spaced apart along the radial direction of the rotor punching 100, each magnetic slot group 1 includes at least one magnetic slot 2, a magnetic flux gap is formed between two adjacent magnetic slot groups 1, the magnetic flux gap includes two first magnetic flux gaps 111 and a second magnetic flux gap 121, and the second magnetic flux gap connection 121 is between the two first magnetic flux gaps 111; wherein the magnetic slot 2 of at least one magnetic slot group 1 includes an arc structure 20, so that in the direction from the first magnetic flux gap 111 to the second magnetic flux gap 121, the width of the first magnetic flux gap 111 increases.

[0051] In the technical solution of the present application, a magnetic flux gap is provided between two adjacent magnetic slot groups 1; the magnetic flux gap includes two first magnetic flux gaps 111 and a second magnetic flux gap 121, and the second magnetic flux gap 121 is connected between the two first magnetic flux gaps 111; the magnetic slot of at least one magnetic slot group 1 includes an arc structure 20, so that the width of the first magnetic flux gap 111 increases in the direction from the first magnetic flux gap 111 to the second magnetic flux gap 121; by reasonably designing the positions and shapes of the multiple magnetic slots 1, the width of the first magnetic flux gap 111 increases in the direction from the first magnetic flux gap 111 to the second magnetic flux gap 121. Such a setting can reduce the magnetic density saturation of the rotor punchings, thereby increasing the magnetic flux density of the rotor punchings and reducing the magnetic resistance.

[0052] It should be noted that, in this embodiment, the magnetic slot 2 is used to accommodate magnetic steel.

[0053] The specific material of the rotor punching sheet 100 is not limited, and can be a high magnetic permeability silicon steel sheet, a high strength silicon steel sheet, an amorphous alloy, or an SMC material, which can be selected according to the actual situation. In some embodiments, the material of the rotor punching sheet 100 is an amorphous alloy, and the amorphous alloy material is applied to the rotor punching sheet 100, which can effectively reduce the eddy current flow area, increase the resistance, and thus reduce the high-frequency eddy current loss.

[0054] In some embodiments, see Figure 1 , Figure 2 and Figure 3 , the magnetic slots 2 of each magnetic slot group 1 include an arc structure 20. The arc structure 20 can improve the structural strength of the rotor punching 100, and the arc structure 20 can also increase the rotation speed of the rotor punching 100. Therefore, the multiple magnetic slots 2 on the rotor punching 100 are all set to the arc structure 20, which can solve the technical problem of torque reduction caused by magnetic flux saturation of the rotor punching 100, improve the output torque of the motor, make the motor run under rated working conditions and full load conditions, and improve the working efficiency of the motor.

[0055] See also Figure 3,by Figure 3 In the embodiment, the first direction is taken as an example, the first direction is a radial direction, and the second direction is perpendicular to the first direction on the cross section of the rotor punching 100. Specifically, each magnetic slot 2 includes two side edges arranged oppositely along the first direction, and both side edges are arranged in an arc shape. Each magnetic slot 2 also includes two magnetic barriers arranged oppositely along the second direction, and the two magnetic barriers are arranged between the two side edges. The two arc-shaped side edges constitute an arc structure 20. It should be noted that in this embodiment, the curvature of the two side edges is the same, and the circles where the two side edges are located are concentric circles. Such an arrangement is convenient for processing, and the arc-shaped side edges can enhance the structural strength of the rotating punching sheet, and the arc-shaped side edges can diffuse the force received by the rotor punching sheet 100 in different directions, thereby avoiding the concentration of force and causing the rotor punching sheet 100 to break.

[0056] Please continue reading Figure 1 , Figure 2 and Figure 3 In this embodiment, in the same magnetic slot group 1, the arc structures 20 of multiple magnetic slots 2 have the same curvature. The design of multiple arc structures 20 adopts the optimal arc curvature optimization technology, which can better utilize the space in the rotor punching 100, improve the distribution utilization rate of the magnetic slots 2 in the unit space, increase the magnetic flux area of ​​the motor, improve the air gap magnetic density, and thus reduce the torque pulsation. At the same time, in the same magnetic slot group 1, the arcs of multiple arc structures 20 are the same, which is convenient for processing.

[0057] See also Figure 1 , Figure 2 and Figure 3 In some embodiments, each magnetic slot group 1 has a first symmetry line extending along the radial direction of the rotor punching 100, and the magnetic slots 2 of each magnetic slot group 1 are symmetrically arranged along the first symmetry line. Such an arrangement can avoid stress concentration, increase the speed of the motor, and thus improve the working efficiency of the motor. Two adjacent magnetic slot groups 1 are a first sub-magnetic slot group 21 and a second sub-magnetic slot group 22. The first sub-magnetic slot group 21 is located outside the second sub-magnetic slot group 22. The multiple magnetic slots 2 of the first sub-magnetic slot group 21 are distributed along the first symmetry line, and the multiple magnetic slots 2 of the second sub-magnetic slot group 22 are distributed along the first symmetry line, wherein, in the second sub-magnetic slot group 22, the magnetic slots 2 closer to the first symmetry line have a larger angle with the first symmetry line. In this way, the second sub-magnetic slot group 22 can surround the first sub-magnetic slot 211 in an approximately circular arc shape. The circular arc shape can disperse stress in different directions, thereby avoiding stress concentration, increasing the speed of the motor, and thus improving the working efficiency of the motor.

[0058] Furthermore, in some embodiments, the first symmetry lines of the plurality of magnetic slot groups 1 are overlapped. The plurality of magnetic slot groups 1 are arranged regularly, and the space in the rotor punching 100 is reasonably utilized, the distribution utilization rate of the magnetic slots 2 in the unit space is improved, the magnetic flux area of ​​the motor is increased, the air gap magnetic density is improved, and the torque pulsation is reduced.

[0059] It should be noted that the bending direction of the arc structure 20 is not limited, as long as the width of the second magnetic flux gap 121 between the magnetic slot group 1 with the arc structure 20 and the adjacent magnetic slot group 1 in two adjacent magnetic slot groups 1 is greater than the width of the first magnetic flux gap 111. In some embodiments, the center of curvature of the arc structure 20 is located on the outside of the arc structure 20, and in other embodiments, the center of curvature of the arc structure 20 is located on the inside of the arc structure 20. It should be noted that in the above embodiments, the inside and the outside are defined by the inside and the outside of the rotor punching 100. In the rotor punching 100, the side corresponding to the shaft is the inside, and the side corresponding to the stator assembly is the outside. Similarly, the side of the arc structure 20 corresponding to the inside of the rotor punching 100 is the inside of the arc structure 20, and the side of the arc structure 20 corresponding to the outside of the rotor punching 100 is the outside of the arc structure 20.

[0060] It should be noted that in the same magnetic slot group 1, a magnetic bridge is formed between two adjacent magnetic slots 2. At the same time, as the motor speed increases, in order to overcome the centrifugal force, the width of the magnetic bridge should be increased as much as possible, and at the same time, the number of magnetic slots 2 should be increased to minimize stress problems. On the other hand, the increase in the width of the magnetic bridge or the increase in the number of magnetic slots 2 will increase the permanent magnet leakage of the rotor punching 100, reduce the effective magnetic flux of the motor, and cause the motor output capacity to decrease.

[0061] The number of magnetic slot structures 10 is the number of motor poles. Under the same magnetic slot structure 10, the sum of the number of magnetic slots 2 is the magnetic pair number of the motor. The number of magnetic slot structures 10 of the rotor punching 100 is n1, and the number of magnetic slots 2 in each magnetic slot structure 10 is n2. When the motor is at a certain speed, the more poles it has, the more the number of magnetic slot structures 10 of the motor increases accordingly, and the stronger the ability to overcome centrifugal force. However, the increase in the number of pole pairs leads to an increase in the motor frequency, and the iron loss also increases, reducing the motor efficiency. At the same time, the increase in the number of magnetic slots 2 may cause an increase in leakage flux to a certain extent, requiring more armature magnetic fields to provide the same torque.

[0062] The saturation magnetic flux density of amorphous alloys is low, and the tensile strength of amorphous alloys is high because there is no lattice or grain boundary. In summary, considering the magnetic properties and mechanical properties of amorphous alloys, combined with the influence of stamping or other processing methods on the mechanical properties of amorphous alloys, through a large number of analyses, it is concluded that 0.5≤n1 / n2≤5.33, n1 and n2 are integers. Within the above range, it can be ensured that the amorphous alloy has enough magnetic slots 2 to overcome the influence of centrifugal force during high-speed rotation, while minimizing the problem of increased leakage magnetic flux.

[0063] In some embodiments, see Figure 1 , Figure 2 and Figure 3, the two adjacent magnetic slot groups 1 are the first sub-magnetic slot group 21 and the second sub-magnetic slot group 22, the first sub-magnetic slot group 21 is located outside the second sub-magnetic slot group 22, the arc of the arc structure 20 of the first sub-magnetic slot group 21 is θ1, and the arc of the arc structure 20 of the second sub-magnetic slot group 22 is θ2, 0.0625≤θ1 / θ2≤14. It should be noted that the space in the rotor is utilized to the maximum extent, the magnetomotive force of the arc-shaped magnetic steel is fully utilized, and the volume utilization rate of the permanent magnet is improved. When θ1 / θ2 is less than 0.0625, or θ1 / θ2 is greater than 14, the structural strength of the sub-punch is insufficient, and the risk of fracture failure is prone to occur, and the space of the rotor punching sheet 100 and the magnetomotive force of the arc-shaped magnetic steel cannot be fully utilized, which will cause the output torque and performance of the motor to decrease, and the arc structure 20 cannot play a role.

[0064] See also Figure 4 and Figure 5 , Figure 4 Schematic diagram of the air gap magnetic flux density of the rotor punching 100 with an arc structure 20, Figure 5 The schematic diagram of the air gap magnetic flux density of the rotor punching 100 with a straight structure is shown in FIG. Figure 4 and Figure 5 It can be concluded that when 0.0625≤θ1 / θ2≤14, the space inside the rotor punching 100 can be utilized to the maximum extent, the magnetomotive force of the arc structure 20 can be fully utilized, and the volume utilization rate of the permanent magnet can be improved, thereby achieving a no-load air gap magnetic flux waveform different from that of a traditional straight-plate permanent magnet motor and reducing torque pulsation.

[0065] Amorphous alloys have advantages such as low loss and good mechanical strength, but they also have problems such as low saturation magnetic flux density. When the magnetic flux density of amorphous alloys is within the range of 1.5 to 1.8 T, the magnetic permeability nearby is close to that of air, that is, its saturation magnetic flux density is very low. Figure 6 and Figure 7 , Figure 6 Schematic diagram of magnetic flux density of the rotor punching 100 with arc junction, Figure 7 The magnetic flux density diagram of the rotor punching sheet 100 with a straight structure is shown in FIG. Figure 6 and Figure 7 Through finite element simulation, it can be concluded that the saturation area is mainly concentrated in the narrow area of ​​the interlayer magnetic steel of the magnetic slot group 1 of the rotor punching 100. In order to avoid the above situation, when the motor is running at full load and rated conditions, the local maximum magnetic flux density of the rotor punching 100 does not exceed 1.8T, thereby improving the torque drop caused by excessive saturation of magnetic flux density and ensuring that the motor does not deteriorate in performance due to saturation.

[0066] In some embodiments, see Figure 1 and Fig.16The rotor punching 100 includes a plurality of sector regions 3, which are connected end to end along the circumferential direction of the rotor punching 100; each sector region 3 is provided with a magnetic slot structure 10, each magnetic slot structure 10 includes at least one arc structure 20, the arc of the sector region 3 is α1, and the arc of the arc structure 20 is α2. Through a large number of calculations, it is concluded that 0.056≤α1 / α2≤2, within which range the flow path can be increased and the local saturation area can be reduced to achieve a higher magnetic flux density and a lower magnetic resistance.

[0067] In some embodiments, the rotor punching sheet 100 includes a plurality of magnetic isolation bridges 4. It should be noted that the specific position of the magnetic isolation bridge 4 is not limited. In the same magnetic slot group 1, a magnetic isolation bridge 4 is formed between two adjacent magnetic slots 2, and a magnetic isolation bridge 4 is formed between the magnetic slot 2 and the outer side of the rotor punching sheet 100. Considering the high-speed operation and minimizing the performance deterioration caused by magnetic tape leakage, the width of the magnetic isolation bridge 4 should be reduced as much as possible. However, in order to overcome the high-speed centrifugal force, the width of the magnetic isolation bridge 4 needs to be optimized. Amorphous alloys have high tensile strength, but they are easily deformed. Their strain should be reduced as much as possible to avoid breaking due to excessive strain that causes them to approach the stress limit. Through a large number of calculations, it is concluded that when the linear speed of the rotor assembly design is greater than or equal to 160m / s. Further, the width of each magnetic isolation bridge 4 is L, 0.5mm≤L≤4.5mm. The width of the magnetic isolation bridge 4 needs to be greater than or equal to 0.5 mm, so as to ensure that the strain does not exceed the bearing limit of the amorphous alloy, and the stress value is greater than or equal to 500 MPa, taking advantage of the high tensile strength of the amorphous alloy and not causing excessive strain to cause it to break.

[0068] See also Figure 1 , Figure 2 and Figure 3 , the two adjacent magnetic slot groups 1 are respectively the first sub-magnetic slot group 21 and the second sub-magnetic slot group 22, the first sub-magnetic slot group 21 is located outside the second sub-magnetic slot group 22, the curvature center of the arc structure 20 of the first sub-magnetic slot group 21 is located on the side of the first sub-magnetic slot 211 away from the second sub-magnetic slot group 22, the arc structure 20 of the second sub-magnetic slot group 22 has a side wall 221, the side wall 221 is close to the first sub-magnetic slot group 21, the side wall 221 includes two side portions 222 opposite to each other in the extension direction of the side wall 221, wherein the minimum distance between the side wall 221 and the magnetic slot 2 of the first sub-magnetic slot group 21 is w1, and the minimum distance between the virtual connecting line segment between the two side portions 222 and the magnetic slot 2 of the first sub-magnetic slot group 21 is w2.

[0069] Figure 8 is the analytical model of the motor’s magnetic circuit. Figure 8It can be concluded that in the rotor assembly, the focus of the d-axis magnetic field and the q-axis magnetic field is at the black dot position in the above figure, that is, the armature and permanent magnet magnetic fields are superimposed, and the highest magnetic density point of the rotor is located at the black dot in the magnetic circuit. Figure 6 The reason why the local saturation point of the rotor punching 100 in the finite element simulation is located at the narrowest part of the rotor magnetic steel layer bond is that, in order to solve the above problem, it is possible to consider optimizing the size of the local saturation area near the black point in the figure.

[0070] In the actual optimization process, the second sub-magnetic slot group 22 is moved toward the inner diameter direction of the rotor punching 100, which can increase the flow width of the q-axis magnetic field here, thereby reducing the q-axis magnetic resistance and its saturation degree. But on the other hand, when the second sub-magnetic slot group 22 shrinks inward, the length of the magnetic steel magnetic field will be lengthened, that is, the flow length of the d-axis magnetic field will increase, and the d-axis magnetic resistance will increase. This will lead to an increase in the salient pole ratio (Ld / Lq) of the motor, but the magnetic resistance of the permanent magnetic field flow path will also increase, resulting in a decrease in the permanent magnetic flux, and ultimately reducing the output torque. Through the above analysis, local saturation is caused by the interaction between the armature magnetic field and the permanent magnetic field, and both magnetic fields produce a large amount of magnetic pressure drop on the air gap. Within a certain range of electromagnetic air gap length, the magnetic resistance of the air gap is inversely proportional to the cross-sectional area of ​​the air gap, that is, the magnetic resistance is inversely proportional to the radius of the rotor punching 100. In summary, the saturation degree of the rotor punching 100 is directly related to the cross-axis distance (roughly the radius of the rotor punching 100) and the straight-axis distance (roughly the distance w1 between the magnetic slot groups 1 of the rotor punching 100). Through a large number of calculations, it is concluded that 1.03≤w1 / w2≤3. Within the above range, the area of ​​the local saturation region will be reduced, and the working efficiency of the motor will be improved. When w1 / w2 is less than 1.03, the local magnetic saturation area of ​​the rotor punching 100 is too large, affecting the output performance of the motor. When w1 / w2 is greater than 3, the distance between the inner magnetic slot groups 1 is too far, the magnetic resistance becomes larger, the magnetic flux density decreases, the output performance is affected, and the utilization rate of the permanent magnet is lower.

[0071] It should be noted that the arrangement of the magnetic slot group 1 is not limited and can be selected according to actual conditions.

[0072] In some embodiments, see Fig. 9Each magnetic groove structure 10 includes two magnetic groove groups 1, and the two magnetic groove groups 1 are respectively a first sub-magnetic groove group 21 and a second sub-magnetic groove group 22. The first sub-magnetic groove group 21 is located outside the second sub-magnetic groove group 22. The first sub-magnetic groove group 21 includes a first sub-magnetic groove 211, and the first sub-magnetic groove 211 is symmetrically arranged along the first symmetry line (that is, the midline of the first sub-magnetic groove 211 coincides with the first symmetry line). The second sub-magnetic groove group 22 includes two second sub-magnetic grooves 223, and the two second sub-magnetic grooves 223 are symmetrically arranged along the first symmetry line. The radius of curvature of the arc structure 20 of the first sub-magnetic groove 211 is located on the side of the first sub-magnetic groove 211 facing the second sub-magnetic groove 223, and the radius of curvature of the arc structure 20 of the two second sub-magnetic grooves 223 is located on the side of the two second sub-magnetic grooves 223 facing the first sub-magnetic groove 211. In this way, the width of the second magnetic flux gap 121 of the first sub-magnetic slot group 21 and the second sub-magnetic slot group 22 is greater than the width of the first magnetic flux gap 111; by reasonably designing the positions and shapes of the multiple magnetic slots 2, the width of the magnetic flux gap is increased, and the problem of output torque reduction caused by magnetic flux saturation is improved, thereby increasing the output torque of the motor, allowing the motor to operate under rated conditions and full load conditions, thereby improving the working efficiency of the motor.

[0073] In some implementations, see Fig.10 Each magnetic groove structure 10 includes two magnetic groove groups 1, and the two magnetic groove groups 1 are respectively a first sub-magnetic groove group 21 and a second sub-magnetic groove group 22. The first sub-magnetic groove group 21 is located outside the second sub-magnetic groove group 22. The first sub-magnetic groove group 21 includes a first sub-magnetic groove 211, and the first sub-magnetic groove 211 is symmetrically arranged along the first symmetry line (that is, the midline of the first sub-magnetic groove 211 coincides with the first symmetry line). The second sub-magnetic groove group 22 includes three second sub-magnetic grooves 223, and the three second sub-magnetic grooves 223 are symmetrically arranged along the first symmetry line. The radius of curvature of the arc structure 20 of the first sub-magnetic groove 211 is located on the side of the first sub-magnetic groove 211 facing the second sub-magnetic groove 223, and the radius of curvature of the arc structure 20 of the three second sub-magnetic grooves 223 is located on the side of the three second sub-magnetic grooves 223 facing the first sub-magnetic groove 211. In this way, the width of the second magnetic flux gap 121 of the first sub-magnetic slot group 21 and the second sub-magnetic slot group 22 is greater than the width of the first magnetic flux gap 111; by reasonably designing the positions and shapes of the multiple magnetic slots 2, the width of the magnetic flux gap is increased, and the problem of output torque reduction caused by magnetic flux saturation is improved, thereby increasing the output torque of the motor, allowing the motor to operate under rated conditions and full load conditions, thereby improving the working efficiency of the motor.

[0074] In some embodiments, see Fig.11Each magnetic groove structure 10 includes two magnetic groove groups 1, and the two magnetic groove groups 1 are respectively a first sub-magnetic groove group 21 and a second sub-magnetic groove group 22. The first sub-magnetic groove group 21 is located outside the second sub-magnetic groove group 22. The first sub-magnetic groove group 21 includes two first sub-magnetic grooves 211, and the two first sub-magnetic grooves 211 are symmetrically arranged along the first symmetry line. The second sub-magnetic groove group 22 includes two second sub-magnetic grooves 223, and the two second sub-magnetic grooves 223 are symmetrically arranged along the first symmetry line. The radius of curvature of the arc structure 20 of the first sub-magnetic groove 211 is located on the side of the first sub-magnetic groove 211 away from the second sub-magnetic groove 223, and the radius of curvature of the arc structure 20 of the two second sub-magnetic grooves 223 is located on the side of the two second sub-magnetic grooves 223 facing the first sub-magnetic groove 211. In this way, the width of the second magnetic flux gap 121 of the first sub-magnetic slot group 21 and the second sub-magnetic slot group 22 is greater than the width of the first magnetic flux gap 111; by reasonably designing the positions and shapes of the multiple magnetic slots 2, the width of the magnetic flux gap is increased, and the problem of output torque reduction caused by magnetic flux saturation is improved, thereby increasing the output torque of the motor, allowing the motor to operate under rated conditions and full load conditions, thereby improving the working efficiency of the motor.

[0075] In some embodiments, see Fig.12 Each magnetic groove structure 10 includes three magnetic groove groups 1, and the three magnetic groove groups 1 are respectively a first sub-magnetic groove group 21, a second sub-magnetic groove group 22 and a third sub-magnetic groove group 23. The second sub-magnetic groove group 22 is located between the first sub-magnetic groove group 21 and the third sub-magnetic groove group 23. The first sub-magnetic groove group 21 includes two first sub-magnetic grooves 211, and the two first sub-magnetic grooves 211 are symmetrically arranged along the first symmetry line. The second sub-magnetic groove group 22 includes two second sub-magnetic grooves 223, and the two second sub-magnetic grooves 223 are symmetrically arranged along the first symmetry line. The magnetic slot group 23 includes two third sub-magnetic slots 231, and the two third sub-magnetic slots 231 are symmetrically arranged along the first symmetry line. The radius of curvature of the arc structure 20 of the first sub-magnetic slot 211 is located on the side of the first sub-magnetic slot 211 away from the second sub-magnetic slot 223, the radius of curvature of the arc structure 20 of the second sub-magnetic slot 223 is located on the side of the second sub-magnetic slot 223 facing the first sub-magnetic slot 211, and the radius of curvature of the arc structure 20 of the third sub-magnetic slot 231 is located on the side of the third sub-magnetic slot 231 facing the second sub-magnetic slot 223. By reasonably designing the positions and shapes of the multiple magnetic slots 2, the width of the magnetic flux gap is increased, and the problem of output torque reduction caused by magnetic density saturation is improved, thereby improving the output torque of the motor, allowing the motor to operate under rated conditions and full-load conditions, and improving the working efficiency of the motor.

[0076] In some embodiments, see Fig.13Each magnetic groove structure 10 includes two magnetic groove groups 1, and the two magnetic groove groups 1 are respectively a first sub-magnetic groove group 21 and a second sub-magnetic groove group 22. The first sub-magnetic groove group 21 is located outside the second sub-magnetic groove group 22. The first sub-magnetic groove group 21 includes three first sub-magnetic grooves 211, and the three first sub-magnetic grooves 211 are symmetrically arranged along the first symmetry line. The second sub-magnetic groove group 22 includes three second sub-magnetic grooves 223, and the three second sub-magnetic grooves 223 are symmetrically arranged along the first symmetry line. The curvature radius of the arc structure 20 of the three first sub-magnetic grooves 211 is located on the side of the first sub-magnetic groove 211 away from the second sub-magnetic groove 223, and the curvature radius of the arc structure 20 of the three second sub-magnetic grooves 223 is located on the side of the three second sub-magnetic grooves 223 facing the first sub-magnetic groove 211. In this way, the width of the second magnetic flux gap 121 of the first sub-magnetic slot group 21 and the second sub-magnetic slot group 22 is greater than the width of the first magnetic flux gap 111; by reasonably designing the positions and shapes of the multiple magnetic slots 2, the width of the magnetic flux gap is increased, and the problem of output torque reduction caused by magnetic flux saturation is improved, thereby increasing the output torque of the motor, allowing the motor to operate under rated conditions and full load conditions, thereby improving the working efficiency of the motor.

[0077] In some embodiments, see Fig.14 Each magnetic groove structure 10 includes two magnetic groove groups 1, the two magnetic groove groups 1 are respectively a first sub-magnetic groove group 21 and a second sub-magnetic groove group 22, the first sub-magnetic groove group 21 is located outside the second sub-magnetic groove group 22, the first sub-magnetic groove group 21 includes two first sub-magnetic grooves 211, the two first sub-magnetic grooves 211 are symmetrically arranged along the first symmetry line, the second sub-magnetic groove group 22 includes three second sub-magnetic grooves 223, the three second sub-magnetic grooves 223 are symmetrically arranged along the first symmetry line, the curvature radius of the arc structure 20 of the first sub-magnetic groove 211 is located on the side of the first sub-magnetic groove 211 away from the second sub-magnetic groove 223, and the curvature radius of the arc structure 20 of the three second sub-magnetic grooves 223 is located on the side of the three second sub-magnetic grooves 223 facing the first sub-magnetic groove 211. In this way, the width of the second magnetic flux gap 121 of the first sub-magnetic slot group 21 and the second sub-magnetic slot group 22 is greater than the width of the first magnetic flux gap 111; by reasonably designing the positions and shapes of the multiple magnetic slots 2, the width of the magnetic flux gap is increased, and the problem of output torque reduction caused by magnetic flux saturation is improved, thereby increasing the output torque of the motor, allowing the motor to operate under rated conditions and full load conditions, thereby improving the working efficiency of the motor.

[0078] According to a second aspect of the present application, a rotor assembly is provided, which is formed by stacking the above-mentioned rotor punchings 100. The rotor assembly has all the beneficial effects of the above-mentioned rotor punchings 100, which will not be described in detail in the present application.

[0079] According to a third aspect of the present application, a motor is provided, the motor comprising a housing and a motor shaft, the housing is provided with a stator assembly, the motor shaft is rotatably mounted in the housing, and the motor shaft is provided with a rotor assembly. The specific structure of the rotor assembly refers to the above embodiment, and since the present 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.

[0080] In some embodiments, the motor further comprises a plurality of magnetic steels, and the plurality of magnetic steels are correspondingly arranged in the plurality of magnetic slots 2. Specifically, the magnetic steel provided in the present application is prepared by a thermal deformation permanent magnet preparation process, and the process flow chart is as follows: Fig.15 shown.

[0081] For details, please continue to see Fig.15 , first use the rapid quenching method, HDDR method or mechanical alloying method to prepare magnetic powder, refine and heat treat the magnetic powder to obtain refined magnetic powder, cold press the magnetic powder to obtain a magnet, and hot press it at a temperature of 550-800°C to make the grains grow and rotate to obtain an isotropic permanent magnet, and then put it into a special mold for hot deformation forming process at a temperature of 800-900°C to prepare anisotropic arc-shaped hot deformation permanent magnets; hot deformation permanent magnets have the advantages of low rare earth content, good thermal stability, magnetic properties consistent with sintered permanent magnets, short manufacturing process, and high degree of freedom in processing shape; because its grain size is refined, it helps to reduce the forming pressure and increase the coercive force, and can achieve near-net forming, saving production and manufacturing costs. Hot deformation permanent magnets are magnetic steel.

[0082] According to a fourth aspect of the present application, a drive assembly is provided, which includes the above-mentioned motor. The drive assembly has all the beneficial effects of the above-mentioned motor, which will not be described in detail in the present application.

[0083] According to a fifth aspect of the present application, a vehicle is provided, which includes the above-mentioned drive assembly. The vehicle has all the beneficial effects of the above-mentioned drive assembly, which will not be described in detail in the present application.

[0084] The vehicle may be a fuel vehicle, a plug-in hybrid vehicle or a new energy vehicle, etc., and this application does not make any specific limitation on this.

[0085] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0086] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0087] The embodiments, implementation methods and related technical features of the present application can be combined and replaced with each other without conflict.

[0088] The above are only preferred embodiments of the present application and do not constitute any form of limitation to the present application. However, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present application without departing from the content of the technical solution of the present application are still within the scope of the technical solution of the present application.

Claims

1. A rotor punching, characterized in that: At least one magnetic slot structure is formed on the rotor punching sheet, each of the magnetic slot structures includes a plurality of magnetic slot groups spaced apart in a radial direction of the rotor punching sheet, each of the magnetic slot groups includes at least one magnetic slot, a magnetic flux gap is formed between two adjacent magnetic slot groups, the magnetic flux gap includes two first magnetic flux gaps and a second magnetic flux gap, and the second magnetic flux gap is connected between the two first magnetic flux gaps; Wherein, the magnetic slot of at least one of the magnetic slot groups comprises an arc-shaped structure, so that the width of the first magnetic flux gap increases in the direction from the first magnetic flux gap to the second magnetic flux gap.

2. The rotor punching according to claim 1, characterized in that: The material of the rotor punching sheet includes amorphous alloy.

3. The rotor punching according to claim 1, characterized in that: The magnetic groove of each magnetic groove group includes an arc-shaped structure.

4. The rotor punching according to claim 1, characterized in that: In the same magnetic slot group, the arc structures of a plurality of magnetic slots have the same curvature.

5. The rotor punching according to claim 1, characterized in that: Each of the magnetic slot groups has a first symmetry line extending in the radial direction of the rotor punching sheet, and the magnetic slots of each of the magnetic slot groups are symmetrically arranged along the first symmetry line.

6. The rotor punching according to claim 5, characterized in that: The first symmetry lines of the plurality of magnetic slot groups are arranged to overlap.

7. The rotor punching according to claim 1, characterized in that: The center of curvature of the arc-shaped structure is located on the outside or inside of the arc-shaped structure.

8. The rotor punching according to claim 1, characterized in that: The number of the magnetic slot structures of the rotor punching sheet is n1, the number of the magnetic slots in each of the magnetic slot structures is n2, n1 and n2 are integers, and 0.5≤n1 / n2≤5.

33.

9. The rotor punching according to claim 1, characterized in that: The two adjacent magnetic groove groups are the first sub-magnetic groove group and the second sub-magnetic groove group. The first sub-magnetic groove group is located outside the second sub-magnetic groove group. The curvature of the arc structure of the first sub-magnetic groove group is θ1, and the curvature of the arc structure of the second sub-magnetic groove group is θ2. 0.0625≤θ1 / θ2≤14.

10. The rotor punching according to claim 1, characterized in that: The rotor punching sheet includes a plurality of fan-shaped areas, and the plurality of fan-shaped areas are connected along the circumferential end of the rotor punching sheet. The head section and the tail end of the plurality of fan-shaped areas are connected. A magnetic groove structure is provided on each of the fan-shaped areas, and each of the magnetic groove structures includes at least one arc structure. The curvature of the fan-shaped area is α1, and the curvature of the arc structure is α2, and 0.056≤α1 / α2≤2.

11. The rotor punching according to claim 1, characterized in that: A plurality of magnetic isolation bridges are also formed on the rotor punching sheet, and the width of each magnetic isolation bridge is L, 0.5mm≤L≤4.5mm.

12. The rotor punching according to claim 1, characterized in that: The two adjacent magnetic groove groups are respectively the first sub-magnetic groove group and the second sub-magnetic groove group, the first sub-magnetic groove group is located outside the second sub-magnetic groove group, the arc-shaped structure of the second sub-magnetic groove group has a side wall, the side wall is close to the first sub-magnetic groove group, and the side wall includes two side portions opposite to each other in the extension direction of the side wall, wherein the minimum distance between the side wall and the magnetic groove of the first sub-magnetic groove group is w1, and the minimum distance between the virtual connecting line segment between the two side portions and the magnetic groove of the first sub-magnetic groove group is w2, and 1.03≤w1 / w2≤3.

13. A rotor assembly, characterized in that: The rotor is formed by stacking a plurality of rotor laminations according to any one of claims 1 to 12.

14. A motor, characterized in that: Comprising a rotor assembly as claimed in claim 13.

15. A drive assembly, characterized in that: Comprising the motor as claimed in claim 14.

16. A vehicle, characterized in that: Comprising the drive assembly as claimed in claim 15.

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