Motor, power system and vehicle

Abstract

The invention provides a motor, a power system and a vehicle. The motor comprises: a stator core; the rotor iron core is rotatably arranged in the stator iron core, an air gap is enclosed between the outer peripheral wall of the rotor iron core and the inner peripheral wall of the stator iron core, the maximum value of the air gap is recorded as H1 from the rotor iron core to the stator iron core, and the minimum value of the air gap is recorded as H2; the rotor core is provided with a shaft hole and a plurality of magnetic pole parts, and the plurality of magnetic pole parts are arranged around the shaft hole at intervals; any one of the plurality of magnetic pole parts comprises a first magnetic slot group and a second magnetic slot group; an included angle formed by the first radial extension line and the second radial extension line is recorded as theta 1; an included angle formed by the third radial extension line and the fourth radial extension line is recorded as theta 2; wherein 0.12 < = (H1-H2) / (H1 + H2) < = 0.33, and 1.64 < = theta2 / theta1 < = 2.1.

Description

Technical Field

[0001] This application relates to the technical field of motors, and in particular, to a motor, a power system, and a vehicle. Background Art

[0002] The motor is the core component of the driving device of an electric vehicle and is applied to various electric vehicles. The performance of the motor directly affects the performance of the entire vehicle.

[0003] In the related art, the motor includes a stator and a rotor. Due to the unreasonable structures of the stator and the rotor, the operating parameter indicators of the motor are adversely affected. For example, the operating noise of the motor is large, and the service life of the motor is short. In this way, the use performance of the electric vehicle is seriously affected. Summary of the Invention

[0004] This application aims to solve at least one of the technical problems existing in the prior art or related technologies.

[0005] To this end, a first aspect of this application proposes a motor.

[0006] A second aspect of this application proposes a power system.

[0007] A third aspect of this application proposes a vehicle.

[0008] In view of this, a first aspect of the present application provides a motor, comprising: a stator core; a rotor core rotatably disposed within the stator core, an air gap being defined between the outer peripheral wall of the rotor core and the inner peripheral wall of the stator core. Along the direction from the rotor core to the stator core, the maximum value of the air gap is denoted as H1, and the minimum value of the air gap is denoted as H2; the rotor core is provided with a shaft hole and a plurality of pole portions, the plurality of pole portions being arranged at intervals around the shaft hole; each pole portion includes a first magnetic slot group and a second magnetic slot group, the second magnetic slot group being located between the first magnetic slot group and the shaft hole; any one of the first magnetic slot group and the second magnetic slot group includes two magnet slots, each magnet slot including an inner end close to the shaft hole and an outer end away from the shaft hole, the inner ends of the two magnet slots being close to each other, the outer ends of the two magnet slots being away from each other, the two magnet slots being symmetrically arranged about the magnetic pole center line of the rotor core, each magnet slot including a permanent magnet segment and a magnetic isolation segment, the permanent magnet segment and the magnetic isolation segment being in communication; in the magnet slot of the first magnetic slot group, the connection points of the permanent magnet segment and the two magnetic isolation segments away from the shaft hole are respectively denoted as a first vertex and a second vertex, a first radial extension line passing through the center of the shaft hole intersects or is tangent to the first vertex, a second radial extension line passing through the center of the shaft hole intersects or is tangent to the second vertex, and the included angle formed by the first radial extension line and the second radial extension line is denoted as θ1; in the magnet slot of the second magnetic slot group, the connection points of the permanent magnet segment and the two magnetic isolation segments away from the shaft hole are respectively denoted as a third vertex and a fourth vertex, a third radial extension line passing through the center of the shaft hole intersects or is tangent to the third vertex, a fourth radial extension line passing through the center of the shaft hole intersects or is tangent to the fourth vertex, and the included angle formed by the third radial extension line and the fourth radial extension line is denoted as θ2; wherein, 0.12 ≤ (H1 - H2) / (H1 + H2) ≤ 0.33, 1.64 ≤ θ2 / θ1 ≤ 2.1.

[0009] A motor provided by the present application includes a stator core and a rotor core, and the stator core and the rotor core are coaxially arranged.

[0010] The stator core is provided with an installation cavity, the rotor core is located within the installation cavity, and the rotor core can rotate about the axis of the stator core. That is to say, the stator core is located outside the rotor core.

[0011] It can be understood that the stator core is provided with a plurality of stator slots, the motor further includes a plurality of winding portions, one winding portion is arranged in any one of the plurality of stator slots, and a permanent magnet is provided within the rotor core. When the motor operates in the motor mode, it can convert electrical energy into mechanical energy.

[0012] Specifically, the controller converts the direct current of the battery into three-phase alternating or tangential current required by the motor. After three-phase alternating or tangential current is introduced into the plurality of winding portions, a tangential magnetic field pulling force will be generated between the stator and the rotor to cause the rotor to rotate, thereby generating a mechanical torque to drive the electric vehicle to move forward.

[0013] It is commonly used in the P3 motor under the hybrid system or the main drive motor in the pure electric drive system. When the motor operates in the generator mode, the rotor of the motor is connected to the engine through the motor shaft or belt, and the engine rotates to drive the rotor to rotate. The multiple winding parts in the alternating stator magnetic field will generate induced current, thereby converting the mechanical energy of the engine into electrical energy. The electrical energy is fed back to the battery or used to drive the motor, and is commonly used in the P1 motor of the hybrid or the range extender system.

[0014] Wherein, the rotor core is provided with a shaft hole and a plurality of magnetic pole parts, and the plurality of magnetic pole parts are arranged at intervals around the shaft hole. Any one of the plurality of magnetic pole parts includes a first magnetic slot group and a second magnetic slot group, that is, each magnetic pole part includes a first magnetic slot group and a second magnetic slot group, and the second magnetic slot group is located between the first magnetic slot group and the shaft hole. The first magnetic slot group includes two magnet slots, and the second magnetic slot group includes two magnet slots.

[0015] The magnet slot includes an inner end and an outer end, the inner end is arranged close to the shaft hole, and the outer end is arranged far from the shaft hole.

[0016] In the first magnetic slot group, the inner ends of the two magnet slots are close to each other, and the outer ends of the two magnet slots are far from each other. That is. The two magnet slots are arranged in a "V" shape.

[0017] In the second magnetic slot group, the inner ends of the two magnet slots are close to each other, and the outer ends of the two magnet slots are far from each other. That is. The two magnet slots are arranged in a "V" shape.

[0018] The second magnetic slot group is located between the first magnetic slot group and the shaft hole, that is, the second magnetic slot group is closer to the shaft hole than the first magnetic slot group.

[0019] In the magnet slot of the first magnetic slot group, the connection point between the side of the permanent magnet segment facing away from the shaft hole and one magnetic isolation segment is denoted as the first vertex A1, and the connection point between the side of the permanent magnet segment facing away from the shaft hole and the other magnetic isolation segment is denoted as the second vertex A2. The first radial extension line passes through the center of the shaft hole, and the first radial extension line intersects or is tangent to the first vertex. The second radial extension line passes through the center of the shaft hole, and the second radial extension line intersects or is tangent to the second vertex.

[0020] In the magnet slot of the second magnetic slot group, the connection point between the side of the permanent magnet segment facing away from the shaft hole and one magnetic isolation segment is denoted as the third vertex A3, and the connection point between the side of the permanent magnet segment facing away from the shaft hole and the other magnetic isolation segment is denoted as the fourth vertex A4. The third radial extension line passes through the center of the shaft hole, and the third radial extension line intersects or is tangent to the third vertex. The fourth radial extension line passes through the center of the shaft hole, and the fourth radial extension line intersects or is tangent to the fourth vertex.

[0021] It can be understood that the first magnetic slot group has a first vertex and a second vertex, and the first vertex and the second vertex are oppositely arranged. The second magnetic slot group has a third vertex and a fourth vertex, and the third vertex and the fourth vertex are oppositely arranged.

[0022] The included angle formed by the first radially extending line and the second radially extending line is denoted as θ1, and the included angle formed by the third radially extending line and the fourth radially extending line is denoted as θ2; where 1.64 ≤ θ2 / θ1 ≤ 2.1. The included angle θ1 is called the pole arc angle of the outer V-shaped magnetic pole structure, and the included angle θ2 is called the pole arc angle of the inner V-shaped magnetic pole structure.

[0023] The values of the pole arc angle θ1 of the outer V-shaped magnetic pole structure and the pole arc angle θ2 of the inner V-shaped magnetic pole structure have a great influence on the output torque, torque ripple, and air-gap magnetic field of the motor. The smaller θ1 is, the larger the electromagnetic torque of the motor is, and the lower the torque ripple is, but the more serious the distortion of the air-gap magnetic field waveform is. And θ2 that matches θ1 indirectly affects various performances of the motor by affecting the direct-axis magnetic circuit and the quadrature-axis magnetic circuit of the motor. For the output torque, when θ2 and θ1 satisfy 1.64 ≤ θ2 / θ1 ≤ 2.1, the reluctance torque component and the permanent magnet torque component of the motor can be reasonably distributed, so as to improve the output torque of the motor without increasing the cost of electromagnetic components.

[0024] In other words, the output torque of the motor is composed of a reluctance torque component and a permanent magnet torque component. Among them, the permanent magnet torque is proportional to the amount of permanent magnet used, the reluctance torque is proportional to the ratio of the quadrature-axis inductance to the direct-axis inductance, and the ratio of the direct-axis and quadrature-axis inductances is directly related to the values of θ1 and θ2. Without increasing the amount of permanent magnet used, by reasonably distributing the values of θ1 and θ2, the ratio of the quadrature-axis inductance to the direct-axis inductance of the motor can be increased, and the reluctance torque component can be improved. When the motor torque of the same size is output, the permanent magnet torque can be smaller. Thus, the amount of permanent magnet used can be reduced, thereby reducing the cost.

[0025] At the same time, the values of θ1 and θ2 are the key factors affecting the air-gap magnetic field distribution of the motor. The torque waveform and no-load back electromotive force waveform of the motor largely depend on the air-gap magnetic field distribution. Among them, the 5th harmonic and 7th harmonic in the air-gap magnetic field will bring 6 times frequency torque ripple, which is the main reason for torque fluctuation. And the 7th harmonic, 11th harmonic, 13th harmonic, 23rd harmonic, and 25th harmonic of these orders of harmonics will cause serious distortion of the no-load back electromotive force waveform, bringing the problem of too high peak value of the no-load line back electromotive force, exceeding the permission range of the motor controller. At the same time, too large harmonics will also bring problems such as too large motor vibration noise, increased loss, reduced efficiency, and temperature rise, thus directly affecting the performance of the motor. By making the above numerical matching for θ1 and θ2, on the basis of ensuring the output torque of the motor, the motor cost can be reduced, the sinusoidality of the air-gap magnetic field can be effectively improved, the harmonics can be reduced, the vibration and noise problems can be improved, the peak value of the no-load line back electromotive force can be reduced, the torque ripple of the motor can be weakened, and the motor efficiency can be improved, so as to realize the design of a high-performance and low-cost motor.

[0026] On the other hand, an air gap is enclosed between the outer peripheral wall of the rotor core and the inner peripheral wall of the stator core, and the air gap is an uneven air gap. Among them, the maximum value of the air gap is denoted as H1, the minimum value of the air gap is denoted as H2, and H1 and H2 satisfy 0.12 ≤ (H1 - H2) / (H1 + H2) ≤ 0.33. For the motor, an unequal air gap that changes periodically in the circumferential direction is formed between the outer peripheral wall of the rotor and the inner peripheral wall of the stator. Combining with the ratio of θ1 and θ2, the air gap magnetic field distribution of the motor is further optimized. On the basis of ensuring the unchanged peak torque of the motor, the torque ripple of the motor is significantly improved, the running vibration noise of the motor is reduced, and the user's comfort in use is improved. At the same time, the iron losses of the stator and rotor of the motor are also reduced to a certain extent, which is beneficial to improving the motor efficiency.

[0027] At the same time, in combination with the selection of θ1 and θ2, the present application reasonably sets the relationship between H1 and H2 so that it satisfies 0.12 ≤ (H1 - H2) / (H1 + H2) ≤ 0.33. In this way, not only the advantages of the integral circular design and the pure eccentric design of the rotor core are taken into account, but also on the basis of not changing the average air gap length of the motor and ensuring the unchanged peak torque of the motor, the air gap magnetic field can be effectively improved, the air gap magnetic density and the sinusoidality of the back electromotive force waveform are increased, the harmonic ratio is reduced, and then the torque ripple is reduced, and the vibration noise of the motor is significantly reduced, which is beneficial to improving the use performance and market competitiveness of the product.

[0028] According to the motor of the present application described above, the following additional technical features may also be provided:

[0029] In some embodiments, optionally, the stator core includes: an annular yoke; a plurality of tooth portions, the plurality of tooth portions are arranged at intervals in the circumferential direction of the stator core, each tooth portion includes a tooth body and a tooth shoe, the tooth body is connected between the tooth shoe and the inner peripheral wall of the annular yoke, and any adjacent two tooth portions and the annular yoke enclose a stator slot, and the tooth shoe is arranged opposite to the rotor core; among any adjacent two tooth portions, along the circumferential direction of the stator core, the side walls of the two tooth bodies close to each other are respectively denoted as the first side wall and the second side wall, and the first side wall and the second side wall are arranged in parallel.

[0030] In this embodiment, the stator core includes an annular yoke and a plurality of tooth portions.

[0031] Any one of the plurality of tooth portions is connected to the inner peripheral wall of the annular yoke, and the plurality of tooth portions are arranged at intervals in the circumferential direction of the stator core.

[0032] Any one of the plurality of tooth portions includes a tooth body and a tooth shoe, and the tooth body is connected between the tooth shoe and the inner peripheral wall of the annular yoke. Among any adjacent two tooth portions, one tooth portion is denoted as the first tooth portion and the other tooth portion is denoted as the second tooth portion. Along the circumferential direction of the stator core, the side wall of the first tooth portion facing the second tooth portion is denoted as the first side wall, and the side wall of the second tooth portion facing the first tooth portion is denoted as the second side wall. The first side wall and the second side wall are arranged in parallel.

[0033] The shape of the tooth body is indirectly defined by defining the mating structure of the first and second side walls. For example, the width of the tooth body in the circumferential direction of the stator core gradually decreases from the annular yoke to the tooth portion. This satisfies the requirement for a parallel arrangement of the first and second side walls. Optionally, both the first and second side walls are planar; alternatively, both the first and second side walls are curved.

[0034] The distance between the first sidewall and the second sidewall can affect the size of the motor's stator slots and the degree of tooth saturation. To ensure a reasonable slot fill rate and current density, the dimensions of the stator core's teeth and stator slots need to be appropriately constrained to ensure motor performance.

[0035] In some embodiments, optionally, along the circumference of the stator core, the width of the end of the tooth body away from the annular yoke is recorded as Wt, and the distance from the first side wall to the second side wall is recorded as Ws, wherein 0.95≤Wt / Ws≤1.45.

[0036] In this embodiment, the structure of the stator core is further defined so that along the circumference of the stator core, the width of the end of the tooth body away from the annular yoke is recorded as Wt, and the distance from the first side wall to the second side wall is recorded as Ws, and the relationship between Wt and Ws is defined so as to satisfy 0.95≤Wt / Ws≤1.45.

[0037] The tooth top width of the tooth body (the tooth top width refers to the width of the end of the tooth body away from the annular yoke along the circumference of the stator core) and the width of the stator slot (the width of the stator slot refers to the distance from the first side wall to the second side wall) directly determine the size of the stator slot of the motor and the degree of saturation of the tooth.

[0038] To ensure a reasonable motor slot fill rate and current density, the dimensions of the motor's teeth and stator slots must be appropriately constrained. Excessively large tooth tip widths and small stator slot widths, or both, can lead to improper stator design, resulting in oversaturated and undersaturated areas of flux density. This leads to high flux leakage in oversaturated areas, waste of material in undersaturated areas, and insufficient cross-linking between the rotor and stator magnetic fields, ultimately hindering full motor performance.

[0039] This results in low motor output torque, high harmonic content, poor back EMF waveforms, low motor efficiency, insufficient stator stiffness, and high vibration and noise. This also increases motor manufacturing costs. To balance motor cost and electromagnetic performance, it's necessary to properly match the motor's tooth tip width and stator slot width.

[0040] Setting the ratio of the motor slotting size parameters within the above range not only realizes reducing the slot leakage magnetic field of the motor while constraining the total stator slot area to remain unchanged, making the parameter matching between the tooth part and the stator slot more reasonable, taking into account both the motor cost and the electromagnetic performance of the motor, with uniform magnetic density distribution, small leakage magnetic field, high copper occupancy ratio of the winding, and high material utilization rate of the motor. While ensuring that the motor has a reasonable current density, it does not increase the manufacturing cost of the motor, maximizing the output torque and efficiency of the motor. Moreover, the stator core has good stiffness, which is beneficial to improving the vibration and noise of the motor. Without the need to increase the material usage or volume envelope, it takes into account the motor efficiency and maximizes the peak torque and peak power output, which is beneficial to improving the use performance of the product and reducing the production cost of the product.

[0041] Optionally, Wt / Ws = 1, Wt / Ws = 1.1, Wt / Ws = 1.2, Wt / Ws = 1.3, and Wt / Ws = 1.4, etc., which are not listed one by one here.

[0042] In some embodiments, optionally, the annular yoke portion is a structure with an equal ring width. The ring width of the annular yoke portion is denoted as Ys, the outer diameter of the stator core is denoted as Ds1, and the split ratio of the stator core is denoted as k. Among them, 0.13 ≤ Ys / (1 - k) / Ds1 ≤ 0.25, 0.65 ≤ k ≤ 0.79.

[0043] In this embodiment, the structure of the stator core is further defined such that the annular yoke portion is a structure with an equal ring width. The ring width of the annular yoke portion is denoted as Ys, the outer diameter of the stator core is denoted as Ds1, and the split ratio of the stator core is denoted as k. Ys, Ds1, and k satisfy 0.13 ≤ Ys / (1 - k) / Ds1 ≤ 0.25, 0.65 ≤ k ≤ 0.79.

[0044] Multiple tooth portions of the stator cooperate with the annular yoke portion, and a stator slot is formed between two adjacent tooth portions and the annular yoke portion. The distance between the bottom surface of the stator slot and the outer peripheral wall of the annular yoke portion forms the ring width of the annular yoke portion. The ring width of the annular yoke portion directly determines the magnetic density of the annular yoke portion, the size of the stator slot, the motor torque output, and the stator stiffness. In order to optimize the magnetic density of the annular yoke portion of the motor and the space of the stator slot on the premise of meeting the motor torque output and the stator stiffness, the motor efficiency can be improved.

[0045] It is necessary to adjust the ring width of the annular yoke, and the ring width of the annular yoke is constrained by the size of the stator itself. That is, constrained by the inner diameter of the stator core and the outer diameter Ds1 of the stator core, the stator split ratio k is equal to the ratio of the inner diameter of the stator core to the outer diameter of the stator core. To this end, the present application reasonably sets the relationship between Ys, k and Ds1 to satisfy 0.13≤Ys / (1-k) / Ds1≤0.25, 0.65≤k≤0.79, and can reasonably allocate the radial proportion of the stator slots and the annular yoke under a limited stator size. Under the premise of taking into account the cost of the motor and the electromagnetic performance of the motor, the output torque and efficiency of the motor are maximized, and the stator core has good stiffness, which is conducive to improving the vibration noise of the motor.

[0046] In some embodiments, optionally, the motor further includes: a plurality of winding parts, any one of the plurality of winding parts is provided in a stator slot, the winding part includes a plurality of winding segments, and the plurality of winding segments are arranged along the direction from the annular yoke to the tooth part; the length of the winding segment in the circumferential direction of the stator core is recorded as L1, and the length of the winding segment in the direction from the tooth part to the annular yoke part is recorded as L2, wherein 1.2≤L1 / L2≤2.5.

[0047] In this embodiment, the stator further includes a plurality of winding parts, and any one of the plurality of winding parts is matched with one stator slot. Specifically, each winding part is provided in one stator slot.

[0048] The winding portion includes a plurality of winding segments, and the plurality of winding segments are arranged in a direction from the annular yoke portion to the tooth portion.

[0049] The winding segments are flat-wire structures. Specifically, the length of the winding segments along the circumference of the stator is L1, and the length of the winding segments along the direction from the teeth to the annular yoke is L2. The relationship between L1 and L2 is defined to satisfy 1.2 ≤ L1 / L2 ≤ 2.5.

[0050] The stator slots are provided with multiple winding segments, which are arranged in the direction from the annular yoke to the teeth. This application defines the relationship between L1 and L2. In particular, in flat wire motors, the size of the flat wire winding segments is relatively large compared to the size of the multi-strand circular wire winding segments, and the single-turn conductor size area is relatively large. When AC is passed through the motor, the number of leakage magnetic turns in each part of the winding section along the slot height direction (i.e., from the bottom of the stator slot to the slot opening) is different, which will generate induced electromotive force of different magnitudes, thereby generating eddy currents, resulting in additional eddy current losses, resulting in reduced motor efficiency and increased temperature rise. Therefore, it is necessary to minimize the size of the flat wire winding segments in the direction from the bottom of the stator slot to the slot opening, and to maximize the ratio of L1 to L2 of the flat wire winding segments, so that the ratio is within the range of 1.2 to 2.5.

[0051] If L1 / L2 > 2.5, it will increase the processing difficulty and manufacturing cost of the product. Therefore, this application limits the value of L1 / L2 to be within the range of 1.2 to 2.5. Not only is the manufacturing and winding process of the winding part less difficult, but the eddy current loss on the winding part is also relatively small, which is beneficial to improving the efficiency of the motor.

[0052] In some embodiments, optionally, the number of stator slots is denoted as s, and the inner diameter of the stator core is denoted as Ds2, where 0.47×π×(Ds2 / s) ≤ Wt ≤ 1.45×Ws.

[0053] In this embodiment, in order to balance the cost of the motor and the electromagnetic performance of the motor, it is necessary to perform a reasonable numerical matching on the tooth part of the stator core and the structure of the stator slots. Make Wt, Ws, s, and Ds2 satisfy 0.47×π×(Ds2 / s) ≤ Wt ≤ 1.45×Ws. In this way, while keeping the total area of the stator slots unchanged, the slot leakage magnetic flux of the motor can be reduced, the parameter matching between the tooth part and the stator slots can be made more reasonable, taking into account the production cost of the motor and the electromagnetic performance of the motor, with uniform magnetic flux density and small leakage magnetic flux, which is beneficial to increasing the copper ratio of the winding and improving the material utilization rate of the motor. While ensuring that the motor has a reasonable current density, without increasing the processing and manufacturing cost of the motor, maximizing the output torque and efficiency of the motor. And the stator core has good stiffness, which is beneficial to improving the vibration and noise of the motor. That is to say, without increasing the production cost of the motor, the efficiency, peak torque, and peak power output of the motor are balanced.

[0054] In some embodiments, optionally, the part of the outer peripheral wall of the rotor core opposite to the magnetic pole part includes an intermediate arc section, a first side arc section, and a second side arc section. The intermediate arc section is located between the first side arc section and the second side arc section, and the intermediate arc section is opposite to the first magnetic slot group; the radius corresponding to any one of the first side arc section and the second side arc section is smaller than the radius corresponding to the intermediate arc section; the value of the gap between one of the first side arc section and the second side arc section and the inner peripheral wall of the stator core is the maximum value of the air gap, and the value of the gap between the intermediate arc section and the inner peripheral wall of the stator core is the minimum value of the air gap.

[0055] In this embodiment, the structure of the rotor core is further defined such that the part of the outer peripheral wall of the rotor core opposite to the magnetic pole part includes an intermediate arc section, a first side arc section, and a second side arc section. The first side arc section is located on the first side of the intermediate arc section, and the second side arc section is located on the second side of the intermediate arc section, that is, the intermediate arc section is located between the first side arc section and the second side arc section. Among them, the intermediate arc section is opposite to the first magnetic slot group.

[0056] Among them, the radius corresponding to the first side arc section is smaller than the radius corresponding to the intermediate arc section, and the radius corresponding to the second side arc section is smaller than the radius corresponding to the intermediate arc section.

[0057] It can be understood that the outer peripheral wall of the rotor core includes an outer peripheral section on the axial end face, and the outer peripheral section is a closed curve.

[0058] The outer peripheral wall of the rotor core includes a plurality of arc segment groups connected in sequence, and one arc segment group corresponds to one magnetic pole portion. It should be noted that the number of arc segment groups and the number of magnetic pole portions are both equal to the number of pole pairs p of the motor.

[0059] Let each arc segment group include at least an intermediate arc segment, a first side arc segment, and a second side arc segment. For the motor, an unequal air gap that varies periodically in the circumferential direction can be formed between the outer peripheral wall of the rotor and the inner peripheral wall of the stator, so as to form an alternation among the first side arc segment, the intermediate arc segment, and the second side arc segment on the outer peripheral wall of the rotor core, which can make the operation of the motor more stable. At the same time, the magnetic field distribution of the rotor is optimized, the armature reaction of the direct and quadrature axes is effectively weakened. Without changing the peak torque of the motor, the torque ripple of the motor is significantly improved, and the running vibration noise of the motor is reduced. At the same time, the iron losses of the stator and rotor of the motor are also reduced to a certain extent, which is beneficial to improving the efficiency of the motor.

[0060] Furthermore, the outer peripheral wall of the rotor core body includes an intermediate arc segment, a first side arc segment, and a second side arc segment. Among them, the radius corresponding to either the first side arc segment or the second side arc segment is smaller than the radius corresponding to the intermediate arc segment. A maximum air gap H1 is formed between the first side arc segment or the second side arc segment and the inner peripheral wall of the stator core, and a minimum air gap H2 is formed between the intermediate arc segment and the inner peripheral wall of the stator core.

[0061] In some embodiments, optionally, among the two magnet slots of the first magnet slot group, the permanent magnet segment of one magnet slot has a third side wall, and the permanent magnet segment of the other magnet slot has a fourth side wall. Either the third side wall or the fourth side wall is arranged facing the outer peripheral wall of the rotor core, and the third side wall and the fourth side wall form an angle b1; among the two magnet slots of the second magnet slot group, the permanent magnet segment of one magnet slot has a fifth side wall, and the permanent magnet segment of the other magnet slot has a sixth side wall. Either the fifth side wall or the sixth side wall is arranged facing the outer peripheral wall of the rotor core, and the fifth side wall and the sixth side wall form an angle b2; wherein, 0°≤b1 - b2≤50°.

[0062] In this embodiment, among the two magnet slots of the first magnet slot group, the permanent magnet segment of one magnet slot has a third side wall, and the permanent magnet segment of the other magnet slot has a fourth side wall. Among the two magnet slots of the second magnet slot group, the permanent magnet segment of one magnet slot has a fifth side wall, and the permanent magnet segment of the other magnet slot has a sixth side wall. Either the third side wall, the fourth side wall, the fifth side wall, or the sixth side wall is arranged facing the outer peripheral wall of the rotor core.

[0063] The third side wall and the fourth side wall form an angle b1, and the fifth side wall and the sixth side wall form an angle b2.

[0064] The included angle b1 is called the outer magnetic pole included angle b1, and the included angle b2 is called the inner magnetic pole included angle b2.

[0065] In a permanent magnet synchronous motor, the values of the pole arc angle θ1 of the outer V-shaped magnetic pole structure and the pole arc angle θ2 of the inner V-shaped magnetic pole structure have a great influence on the magnetic resistance of the direct-axis magnetic circuit of the motor. That is, it has a great influence on the inductance of the direct-axis magnetic circuit. The values of the outer magnetic pole included angle b1 and the inner magnetic pole included angle b2 have a great influence on the magnetic resistance of the quadrature-axis magnetic circuit of the motor. That is, it has a great influence on the inductance of the quadrature-axis magnetic circuit (the smaller the magnetic resistance, the larger the inductance; conversely, the larger the magnetic resistance, the smaller the inductance). The saliency ratio of the motor is the ratio of the quadrature-axis inductance to the direct-axis inductance. The motor torque is the reluctance torque (the electromagnetic torque component generated by the difference between the quadrature-axis and direct-axis inductances of the permanent magnet synchronous motor) plus the permanent magnet torque (the electromagnetic torque component generated by the permanent magnets of the permanent magnet synchronous motor). There is a positive numerical relationship between the amount of permanent magnets used and the permanent magnet torque.

[0066] In this application, by making the above numerical matching for the ratio of the pole arc angle θ1 of the outer V-shaped magnetic pole structure to the pole arc angle θ2 of the inner V-shaped magnetic pole structure, and the ratio of the outer magnetic pole included angle b1 to the inner magnetic pole included angle b2, the ratio of the quadrature-axis inductance to the direct-axis inductance of the motor can be increased, and the saliency ratio can be improved. After the saliency ratio is improved, the utilization rate of the reluctance torque of the motor is also improved. When the motor torque of the same magnitude is output, the permanent magnet torque can be smaller. Thus, the amount of permanent magnets used can be reduced, thereby reducing costs.

[0067] On the other hand, the resultant magnetomotive force of a magnetic pole part is obtained by superimposing the magnetomotive forces generated by the permanent magnets in the first magnetic slot group and the permanent magnets in the second magnetic slot group (abbreviated as the outer magnetomotive force and the inner magnetomotive force). The resultant magnetomotive force is affected not only by the outer magnetomotive force or the inner magnetomotive force alone, but also by the superposition result of the two.

[0068] The waveforms of the resultant magnetomotive force, the outer magnetomotive force, and the inner magnetomotive force all include a fundamental wave and harmonics. The fundamental wave and harmonics in the outer magnetomotive force are related to the pole arc angle θ1 of the outer V-shaped magnetic pole structure and the outer magnetic pole included angle b1, and the fundamental wave and harmonics in the inner magnetomotive force are related to the pole arc angle θ2 of the inner V-shaped magnetic pole structure and the inner magnetic pole included angle b2.

[0069] In this application, by making the above numerical matching for the pole arc angle θ1 of the outer V-shaped magnetic pole structure, the outer magnetic pole included angle b1, the pole arc angle θ2 of the inner V-shaped magnetic pole structure, and the inner magnetic pole included angle b2 at the same time, the waveform of the resultant magnetomotive force can be optimized, the harmonic components in the waveform of the resultant magnetomotive force can be effectively suppressed, the sinusoidality of the air-gap magnetic field waveform can be improved, thereby reducing the cogging torque and torque ripple of the permanent magnet synchronous motor, and reducing the vibration and noise of the motor.

[0070] Moreover, since the included angle of the outer magnetic poles is not equal to the included angle of the inner magnetic poles, more combinations can be generated when the included angles of the outer and inner magnetic poles are numerically matched, thereby enabling more flexible optimization of the waveform of the synthetic magnetic potential to meet the product requirements.

[0071] In some embodiments, optionally, the rotor core is provided with a plurality of weight-reducing holes, which are arranged at intervals. The weight-reducing holes are located on the magnetic pole center line or the inter-pole center line of the rotor core; the number of weight-reducing holes is 2×N1×p, where N1 is a positive integer and p is the number of pole pairs of the motor.

[0072] In this embodiment, the structure of the rotor core is such that the rotor core is provided with a plurality of weight-reducing holes, which are arranged at intervals. Specifically, the plurality of weight-reducing holes are arranged at intervals along the circumferential direction of the shaft hole.

[0073] On the one hand, an overly heavy rotor mass will increase the centrifugal force load of the rotor, reduce the fatigue life of the rotor core, and increase the production cost. Therefore, it is necessary to use weight-reducing holes to reduce the weight of the rotor core. On the other hand, for a motor using rotor oil cooling, oil holes need to be arranged on the rotor core as oil cooling channels to cool the rotor core. The weight-reducing holes can be used as oil holes, reduce the mass of the rotor core, and can also be used as positioning holes to assist in the installation and positioning of the rotor core. Therefore, a plurality of weight-reducing holes are provided on the rotor core in this application.

[0074] Further define the number and distribution position of the weight-reducing holes.

[0075] The weight-reducing holes are located on the magnetic pole center line or the inter-pole center line of the rotor core. For example, any one of the plurality of weight-reducing holes is located on the magnetic pole center line of the rotor core. For another example, any one of the plurality of weight-reducing holes is located on the inter-pole center line of the rotor core. For another example, a part of the plurality of weight-reducing holes is located on the magnetic pole center line of the rotor core, and another part of the plurality of weight-reducing holes is located on the inter-pole center line of the rotor core.

[0076] The number of weight-reducing holes is 2×N1×p, where N1 is a positive integer and p is the number of pole pairs of the motor. For example, the number of weight-reducing holes includes 4, 6, 8, 12, 16 or 20, etc., which are not listed one by one here.

[0077] That is to say, the plurality of weight-reducing holes are in the same circumferential area of the rotor core part. This setting makes the overall structure of the rotor core more uniform and can ensure the balance and consistency of the force.

[0078] At the same time, for a rotor core, it has a magnetic pole center line and an inter-pole center line. Among them, the line connecting the center of the magnetic pole part and the center of the shaft hole forms the magnetic pole center line, which is abbreviated as the d-axis. The angular bisector of two adjacent magnetic pole center lines is the inter-pole center line, and the inter-pole center line is also called the adjacent magnetic pole center line, which is abbreviated as the q-axis.

[0079] The weight-reducing holes are located on the magnetic pole center line or the inter-pole center line of the rotor core. On the premise of ensuring that the motor performance is not affected, the setting of the weight-reducing holes can reduce the moment of inertia and reduce the overall weight of the motor.

[0080] In some embodiments, optionally, the minimum distance from multiple weight-reducing holes to the outer peripheral wall of the rotor core is denoted as L3, the radius of the shaft hole is denoted as R1, and the radius of the rotor core is denoted as R2, where 0.45 ≤ L3 / (R2 - R1) ≤ 0.77.

[0081] In this embodiment, for the structure of the rotor core, among multiple weight-reducing holes, the weight-reducing hole with the minimum distance to the outer peripheral wall of the rotor core is denoted as the weight-reducing reference hole, and the minimum distance from the weight-reducing reference hole to the outer peripheral wall of the rotor core is denoted as L3. The radius of the shaft hole is denoted as R1. The radius of the rotor core is denoted as R2. L3, R1, and R2 satisfy 0.45 ≤ L3 / (R2 - R1) ≤ 0.77. For different outer diameters of the rotating shaft and different outer diameters of the rotor core, the positions of the weight-reducing holes are also different. If the weight-reducing holes are too close to the position of the rotating shaft, it will increase the stress level at the inner side position of the shaft hole. If the weight-reducing holes are too close to the outer peripheral wall of the rotor core, it will affect the stress on the outer peripheral circle side of the rotor core and the magnetic circuit of the motor, and affect the motor torque and strength performance.

[0082] Limiting the minimum distance L3 from multiple weight-reducing holes to the outer peripheral wall of the rotor core, the radius R1 of the shaft hole, and the radius R2 of the rotor core within the above ranges can not only meet the weight reduction requirements but also meet the performance requirements of the motor, and can achieve uniform deformation and force application of the rotor core under centrifugal force load to relieve the stress concentration problem on the rotor core. At the same time, the distribution of its weight-reducing holes has no influence on the electromagnetic performance of the rotor core. In addition, the rotor core of the present application can simultaneously meet the design requirements of rotors in multiple power segments including water cooling and oil cooling, and has the characteristics of platform design.

[0083] In some embodiments, optionally, along the inner end to the outer end, the width of the permanent magnet segment of the first magnetic slot group is denoted as W1, and the width of the permanent magnet segment of the second magnetic slot group is denoted as W2, where 0.17 ≤ (W2 - W1) / (W2 + W1) ≤ 0.49.

[0084] In this embodiment, the structure of the magnetic pole part is further limited.

[0085] Any one of the first magnetic slot group and the second magnetic slot group includes two magnet slots, and the magnet slots penetrate the rotor core along the axial direction of the rotor core, and the magnet slots are used to accommodate the permanent magnets of the rotor.

[0086] Any one of the multiple magnet slots includes a permanent magnet segment and a magnetic isolation segment, and the permanent magnet segment and the magnetic isolation segment are interconnected. Specifically, the permanent magnet segment is used to accommodate the permanent magnet of the rotor, the permanent magnet is embedded in the permanent magnet segment, and no permanent magnet is provided in the magnetic isolation segment, that is, the magnetic isolation segment is empty. The magnetic isolation segment is connected to one side of the permanent magnet segment, or the number of magnetic isolation segments is two, and the permanent magnet segment is connected between the two magnetic isolation segments.

[0087] Among them, the magnetic pole part includes a first magnetic slot group and a second magnetic slot group with a "V" shape. The magnetic fluxes generated by the permanent magnets in the first magnetic slot group and the second magnetic slot group act together (hereinafter, the magnetic flux generated by the first magnetic slot group is simply referred to as the outer magnetic flux, and the magnetic flux generated by the second magnetic slot group is simply referred to as the inner magnetic flux) and are superimposed. The synthesized magnetic flux is affected not only by the outer magnetic flux or the inner magnetic flux alone, but also by the superposition result of the two. Therefore, there is an optimal width ratio between them.

[0088] In this application, by reasonably setting the cooperation structure of the permanent magnet segments of the first magnetic slot group and the second magnetic slot group, along the inner end to the outer end, the width of the permanent magnet segment of the first magnetic slot group is denoted as W1, and the width of the permanent magnet segment of the second magnetic slot group is denoted as W2, where 0.17 ≤ (W2 - W1) / (W2 + W1) ≤ 0.49. Under the optimal width ratio, the synthesized magnetic flux can be reasonably distributed to the d-axis and q-axis of the rotor core, and act together to generate the output torque. In this way, without increasing the material cost or volume envelope of the motor, the peak torque and peak output power of the motor can be significantly improved. It not only improves the utilization rate of the permanent magnets of the rotor, but also can achieve higher torque and power density output.

[0089] Optionally, (W2 - W1) / (W2 + W1) = 0.2, (W2 - W1) / (W2 + W1) = 0.25, (W2 - W1) / (W2 + W1) = 0.28, (W2 - W1) / (W2 + W1) = 0.3, (W2 - W1) / (W2 + W1) = 0.32, (W2 - W1) / (W2 + W1) = 0.35, (W2 - W1) / (W2 + W1) = 0.4, and (W2 - W1) / (W2 + W1) = 0.45, etc., which are not listed one by one here.

[0090] In some embodiments, optionally, along the axial direction of the rotor core, the rotor core includes a plurality of core groups, and each core group includes a plurality of stacked core segments; any two adjacent core segments in the core group are arranged in a circumferential dislocation in the rotor core, and the dislocation angle is denoted as θ. The total number of core segments of the plurality of core groups is denoted as n, n ≥ 2, the number of stator slots is denoted as Z, and the number of pole pairs of the motor is denoted as p; θ = θ0 + Δθ, θ0 = 360° / (n × Nc), Nc = LCM(Z, 2 × p), 0° ≤ Δθ ≤ θ0.

[0091] In this embodiment, along the axial direction of the rotor core, the rotor core includes a plurality of core groups, each core group includes a plurality of core segments, and any two adjacent core segments in the core group are arranged with a circumferential misalignment in the rotor core. That is, the rotor core is assembled in a segmented skewed pole manner, that is, at least two adjacent core segments are arranged with a circumferential misalignment in the rotor core. The misalignment angle is θ, θ = θ0 + Δθ, θ0 = 360° / (n×Nc), where n is the total number of core segments of the plurality of core groups, and n is a natural number greater than or equal to 2. Nc = LCM(Z, 2×p), Z is the number of stator slots, p is the number of pole pairs of the motor, and 0° ≤ Δθ ≤ θ0. Since the permanent magnets in the motor do not change the magnetic strength according to the position and state of the motor, during the circumferential operation, the magnetic poles of the permanent magnets will generate different attractive forces on the stator slots and teeth of the stator. The different attractive forces will cause the torque of the rotor to fluctuate during rotation, and this fluctuation will cause vibration and noise during the operation of the motor.

[0092] Especially for high-power motors such as automotive permanent magnet synchronous motors, the vibration and noise caused by this reason are more obvious.

[0093] However, the optimization combination effect of the structural parameters in the motor has a limited effect on improving the air-gap magnetic field waveform. Especially the tooth harmonics, which are the main sources of the vibration and noise of the motor. Therefore, it is also necessary to combine the segmented skewed pole of the rotor to further weaken the harmonic content. The segmented misaligned pole of the rotor can reduce the cogging torque and torque ripple, thereby reducing the electromagnetic vibration. In other words, by dividing the rotor into a plurality of core groups and making there be a relative rotation angle between different core segments in the core group, the specific harmonic content in the motor can be effectively suppressed, the torque ripple and cogging torque of the motor can be improved, and thus the effect of reducing the vibration and noise of the motor can be achieved.

[0094] The segmented skewed pole can, while ensuring the electromagnetic torque of the motor, reduce the end leakage magnetic flux of the permanent magnet to the greatest extent, improve the utilization rate of the permanent magnet, weaken the cogging torque, and reduce the torque ripple of the motor. At the same time, it can improve the air-gap magnetic field distribution, reduce the distortion rate of the air-gap magnetic field, and improve the noise and vibration performance of the motor.

[0095] The second aspect of the present application proposes a power system, including: the motor as in the first aspect.

[0096] Since the power system provided by the present application includes the motor as in the first aspect, it has all the beneficial effects of the above-mentioned motor, and will not be described one by one here.

[0097] Optionally, the power system includes a motor, a controller, and a reducer. The controller is electrically connected to the motor, the controller is electrically connected to the reducer, and the controller controls the operation of the motor and the reducer. The power system can meet the usage requirements of torque and power for the vehicle to move forward.

[0098] A third aspect of the present application provides a vehicle, comprising: the electric motor as in the first aspect; or the power system as in the second aspect.

[0099] The vehicle provided by the present application includes the electric motor as in the first aspect or the power system as in the second aspect, and thus has all the beneficial effects of the above-mentioned electric motor or power system, which will not be elaborated one by one herein.

[0100] It should be noted that the vehicle can be a new energy vehicle. New energy vehicles include battery electric vehicles, range-extended electric vehicles, hybrid electric vehicles, fuel cell electric vehicles, hydrogen engine vehicles, etc.

[0101] The additional aspects and advantages of the present application will become apparent in the following description section or be learned through the practice of the present application. Description of the Drawings

[0102] The above and / or additional aspects and advantages of the present application will become apparent and be readily understood from the description of the embodiments in conjunction with the following drawings, where:

[0103] Figure 1 Figure 1 shows a schematic diagram of the first part of the structure of the electric motor according to an embodiment of the present application;

[0104] Figure 2 Figure 2 shows a schematic diagram of the second part of the structure of the electric motor according to an embodiment of the present application;

[0105] Figure 3 Figure 3 shows a schematic diagram of the third part of the structure of the electric motor according to an embodiment of the present application;

[0106] Figure 4 Figure 4 shows a schematic diagram of a partial structure of the stator according to an embodiment of the present application;

[0107] Figure 5 Figure 5 shows a schematic diagram of the first part of the structure of the rotor according to an embodiment of the present application;

[0108] Figure 6 Figure 6 shows a schematic diagram of the second part of the structure of the rotor according to an embodiment of the present application;

[0109] Figure 7 Figure 7 shows a schematic diagram of the third part of the structure of the rotor according to an embodiment of the present application;

[0110] Figure 8 Figure 8 shows a schematic diagram of the structure of the rotor from the first perspective according to an embodiment of the present application;

[0111] Figure 9 Figure 9 shows a schematic diagram of the structure of the rotor from the second perspective according to an embodiment of the present application;

[0112] Figure 10 The structural schematic diagram of the stator of an embodiment of the present application is shown;

[0113] Figure 11 The structural schematic diagram of the fourth part of the motor of an embodiment of the present application is shown;

[0114] Figure 12 The data curve diagrams showing the output torque and torque ripple of the present application varying with the change of θ2 / θ1 are given;

[0115] Figure 13 The data curve diagrams showing the torque ripple of the present application varying with the change of (H1 - H2) / (H1 + H2) are given;

[0116] Figure 14 The data curve diagrams showing the total motor loss and motor efficiency of the present application varying with the change of Wt / Ws are given;

[0117] Figure 15 The data curve diagrams showing the peak torque and total motor loss of the present application varying with the change of Ys / (1 - k) / Ds1 are given;

[0118] Figure 16 The data curve diagrams showing the torque of the present application varying with the change of (b1 - b2) are given.

[0119] Among them, Figures 1 to 11 The corresponding relationship between the reference numerals and component names in [the figure] is as follows:

[0120] 1 motor, 10 stator core, 110 annular yoke, 120 tooth part, 122 tooth body, 124 tooth shoe, 130 stator slot, 140 first side wall, 150 second side wall, 20 rotor core, 200 shaft hole, 300 magnetic pole part, 310 first magnetic slot group, 320 second magnetic slot group, 330 magnet slot, 332 inner end, 334 outer end, 336 permanent magnet segment, 338 magnetic isolation segment, 340 third side wall, 350 fourth side wall, 360 fifth side wall, 370 sixth side wall, 410 first radial extension line, 420 second radial extension line, 430 third radial extension line, 440 fourth radial extension line, 510 middle arc segment, 520 first side arc segment, 530 second side arc segment, 600 weight reduction hole, 700 iron core group, 710 iron core segment, 800 air gap, 900 winding part, 910 winding segment, 22 permanent magnet. Detailed implementation manners

[0121] In order to be able to more clearly understand the above objects, features and advantages of the present application, the present application will be further described in detail below in conjunction with the accompanying drawings and specific implementation manners. It should be noted that, without conflict, the embodiments of the present application and the features in the embodiments can be combined with each other.

[0122] In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present application. However, the present application may be implemented in other ways different from those described herein. Therefore, the scope of protection of the present application is not limited by the specific embodiments disclosed below.

[0123] Reference is now made to Figures 1 to 16 An electric motor 1, a power system, and a vehicle according to some embodiments of the present application.

[0124] As Figure 1 、 Figure 2 、 Figure 3 、 Figure 5 、 Figure 6 、 Figure 7 、 Figure 10 and Figure 11 As shown in

[0125] The rotor core 20 is rotatably disposed within the stator core 10.

[0126] An air gap 800 is defined between the outer peripheral wall of the rotor core 20 and the inner peripheral wall of the stator core 10.

[0127] Along the rotor core 20 to the stator core 10, the maximum value of the air gap 800 is denoted as H1, and the minimum value of the air gap 900 is denoted as H2.

[0128] The rotor core 20 is provided with a shaft hole 200 and a plurality of magnetic pole portions 300, and the plurality of magnetic pole portions 300 are arranged at intervals around the shaft hole 200.

[0129] Any one of the plurality of magnetic pole portions 300 includes a first magnetic slot group 310 and a second magnetic slot group 320.

[0130] The second magnetic slot group 320 is located between the first magnetic slot group 310 and the shaft hole 200.

[0131] Any one of the first magnetic slot group 310 and the second magnetic slot group 320 includes two magnet slots 330.

[0132] Any one of the two magnet slots 330 includes an inner end 332 close to the shaft hole 200 and an outer end 334 far from the shaft hole 200.

[0133] The inner ends 332 of the two magnet slots 330 are close to each other.

[0134] The outer ends 334 of the two magnet slots 330 are far from each other.

[0135] The two magnet slots 330 are symmetrically arranged about the magnetic pole center line of the rotor core 20.

[0136] The magnet slot 330 includes a permanent magnet segment 336 and a magnetic isolation segment 338, and the permanent magnet segment 336 and the magnetic isolation segment 338 are in communication.

[0137] In the magnet slot 330 of the first magnet slot group 310, the connection points of the permanent magnet segment 336 and the two magnetic isolation segments 338 facing away from the shaft hole 200 are respectively denoted as the first vertex and the second vertex.

[0138] The first radial extension line 410 passing through the center of the shaft hole 200 intersects or is tangent to the first vertex, and the second radial extension line 420 passing through the center of the shaft hole 200 intersects or is tangent to the second vertex.

[0139] The included angle formed by the first radial extension line 410 and the second radial extension line 420 is denoted as θ1.

[0140] In the magnet slot 330 of the second magnet slot group 320, the connection points of the permanent magnet segment 336 and the two magnetic isolation segments 338 facing away from the shaft hole 200 are respectively denoted as the third vertex and the fourth vertex.

[0141] The third radial extension line 430 passing through the center of the shaft hole 200 intersects or is tangent to the third vertex.

[0142] The fourth radial extension line 440 passing through the center of the shaft hole 200 intersects or is tangent to the fourth vertex.

[0143] The included angle formed by the third radial extension line 430 and the fourth radial extension line 440 is denoted as θ2.

[0144] Wherein, 0.12 ≤ (H1 - H2) / (H1 + H2) ≤ 0.33, 1.64 ≤ θ2 / θ1 ≤ 2.1.

[0145] An electric motor 1 provided by the present application includes a stator core 10 and a rotor core 20, and the stator core 10 and the rotor core 20 are coaxially arranged.

[0146] The stator core 10 is provided with an installation cavity, the rotor core 20 is located in the installation cavity, and the rotor core 20 can rotate around the axis of the stator core 10. That is, the stator core 10 is located outside the rotor core 20.

[0147] It can be understood that the stator core 10 is provided with a plurality of stator slots 130, the electric motor 1 further includes a plurality of winding parts 900, one winding part 900 is arranged in any one of the plurality of stator slots 130, and a permanent magnet 22 is arranged in the rotor core 20. When the electric motor 1 operates in the motor mode, it can convert electrical energy into mechanical energy.

[0148] Specifically, the controller converts the direct current of the battery into three-phase alternating or tangent current required by the motor 1. After three-phase alternating or tangent current is introduced into the multiple winding portions 900, a tangential magnetic field pulling force will be generated between the stator and the rotor to cause the rotor to rotate, thereby generating mechanical torque to drive the electric vehicle to move forward.

[0149] It is commonly used in the P3 motor 1 under a hybrid system or the main drive motor 1 in a pure electric drive system. When the motor 1 operates in the generator 1 mode, the rotor of the motor 1 is connected to the engine through the rotating shaft or belt of the motor 1. The rotation of the engine drives the rotation of the rotor. Induced current will be generated in the multiple winding portions 900 in the alternating stator magnetic field, thereby converting the mechanical energy of the engine into electrical energy. The electrical energy is fed back to the battery or used to drive the electric motor, and it is commonly used in the hybrid P1 motor or the range extender system.

[0150] Among them, the rotor core 20 is provided with a shaft hole 200 and a plurality of pole portions 300. The plurality of pole portions 300 are arranged at intervals around the shaft hole 200. Any one of the plurality of pole portions 300 includes a first magnetic slot group 310 and a second magnetic slot group 320. That is, each pole portion 300 includes a first magnetic slot group 310 and a second magnetic slot group 320. The second magnetic slot group 320 is located between the first magnetic slot group 310 and the shaft hole 200. The first magnetic slot group 310 includes two magnet slots 330, and the second magnetic slot group 320 includes two magnet slots 330.

[0151] The magnet slot 330 includes an inner end 332 and an outer end 334. The inner end 332 is arranged close to the shaft hole 200, and the outer end 334 is arranged far from the shaft hole 200.

[0152] In the first magnetic slot group 310, the inner ends 332 of the two magnet slots 330 are close to each other, and the outer ends 334 of the two magnet slots 330 are far from each other. That is. The two magnet slots 330 are arranged in a "V" shape.

[0153] In the second magnetic slot group 320, the inner ends 332 of the two magnet slots 330 are close to each other, and the outer ends 334 of the two magnet slots 330 are far from each other. That is. The two magnet slots 330 are arranged in a "V" shape.

[0154] The second magnetic slot group 320 is located between the first magnetic slot group 310 and the shaft hole 200. That is, the second magnetic slot group 320 is closer to the shaft hole 200 than the first magnetic slot group 310.

[0155] In the magnet slot 330 of the first magnet slot group 310, the connection point between the side of the permanent magnet segment 336 facing away from the shaft hole 200 and one magnetic isolation segment 338 is denoted as the first vertex A1, and the connection point between the side of the permanent magnet segment 336 facing away from the shaft hole 200 and the other magnetic isolation segment 338 is denoted as the second vertex A2. The first radial extension line 410 passes through the center of the shaft hole 200, and the first radial extension line 410 intersects or is tangent to the first vertex. The second radial extension line 420 passes through the center of the shaft hole 200, and the second radial extension line 420 intersects or is tangent to the second vertex.

[0156] In the magnet slot 330 of the second magnet slot group 320, the connection point between the side of the permanent magnet segment 336 facing away from the shaft hole 200 and one magnetic isolation segment 338 is denoted as the third vertex A3, and the connection point between the side of the permanent magnet segment 336 facing away from the shaft hole 200 and the other magnetic isolation segment 338 is denoted as the fourth vertex A4. The third radial extension line 430 passes through the center of the shaft hole 200, and the third radial extension line 430 intersects or is tangent to the third vertex. The fourth radial extension line 440 passes through the center of the shaft hole 200, and the fourth radial extension line 440 intersects or is tangent to the fourth vertex.

[0157] It can be understood that the first magnet slot group 310 has a first vertex and a second vertex, and the first vertex and the second vertex are arranged oppositely. The second magnet slot group 320 has a third vertex and a fourth vertex, and the third vertex and the fourth vertex are arranged oppositely.

[0158] The included angle formed by the first radial extension line 410 and the second radial extension line 420 is denoted as θ1, and the included angle formed by the third radial extension line 430 and the fourth radial extension line 440 is denoted as θ2; where, 1.64 ≤ θ2 / θ1 ≤ 2.1. The included angle θ1 is called the pole arc angle of the outer V-shaped magnetic pole structure, and the included angle θ2 is called the pole arc angle of the inner V-shaped magnetic pole structure.

[0159] The values of the pole arc angle θ1 of the outer V-shaped magnetic pole structure and the pole arc angle θ2 of the inner V-shaped magnetic pole structure have a great influence on the output torque, torque ripple, and air-gap 800 magnetic field of the motor 1. The smaller θ1 is, the greater the electromagnetic torque of the motor 1 is, and the lower the torque ripple is, but the more serious the waveform distortion of the air-gap 800 magnetic field is. And θ2 matching θ1 indirectly affects various performances of the motor 1 by affecting the direct-axis magnetic circuit and the quadrature-axis magnetic circuit of the motor 1. For the output torque, θ2 and θ1 satisfy 1.64 ≤ θ2 / θ1 ≤ 2.1, which can reasonably distribute the reluctance torque component and the permanent magnet torque component of the motor 1, so as to improve the output torque of the motor 1 without increasing the cost of electromagnetic components.

[0160] In other words, the output torque of the motor 1 consists of a reluctance torque component and a permanent magnet torque component. Among them, the permanent magnet torque is proportional to the amount of the permanent magnet 22, the reluctance torque is proportional to the ratio of the quadrature-axis inductance to the direct-axis inductance, and the ratio of the quadrature-axis inductance to the direct-axis inductance is directly related to the values of θ1 and θ2. Without increasing the amount of the permanent magnet 22, by reasonably allocating the values of θ1 and θ2, the ratio of the quadrature-axis inductance to the direct-axis inductance of the motor 1 can be increased, and the reluctance torque component can be enhanced. When the motor 1 outputs the same torque, the permanent magnet torque can be smaller. Thus, the amount of the permanent magnet 22 can be reduced, and the cost can be lowered accordingly.

[0161] Meanwhile, the values of θ1 and θ2 are the key factors affecting the magnetic field distribution in the air gap 800 of the motor 1. The torque waveform and the no-load back electromotive force waveform of the motor 1 largely depend on the magnetic field distribution in the air gap 800. Among them, the 5th harmonic and the 7th harmonic in the air gap 800 will bring 6-times-frequency torque ripple, which is the main cause of torque fluctuation. And the 7th harmonic, 11th harmonic, 13th harmonic, 23rd harmonic, and 25th harmonic, these harmonics of several orders will cause serious distortion of the no-load back electromotive force waveform, resulting in the problem that the peak value of the no-load line back electromotive force is too high, exceeding the allowable range of the controller of the motor 1. Meanwhile, excessive harmonics will also bring problems such as excessive vibration and noise of the motor 1, increased losses, reduced efficiency, and temperature rise of the motor 1, thus directly affecting the performance of the motor 1. By performing the above numerical matching on θ1 and θ2, on the basis of ensuring the output torque of the motor 1, the cost of the motor 1 can be reduced, the sinusoidality of the magnetic field in the air gap 800 can be effectively improved, the harmonics can be reduced, the vibration and noise problems can be improved, the peak value of the no-load line back electromotive force can be reduced, the torque ripple of the motor 1 can be weakened, and the motor efficiency can be improved, thereby realizing the design of a high-performance and low-cost motor 1.

[0162] On the other hand, an air gap 800 is enclosed between the outer peripheral wall of the rotor core 20 and the inner peripheral wall of the stator core 10, and the air gap 800 is an uneven air gap 800. Among them, the maximum value of the air gap 800 is denoted as H1, the minimum value of the air gap 800 is denoted as H2, and H1 and H2 satisfy 0.12 ≤ (H1 - H2) / (H1 + H2) ≤ 0.33. For the motor 1, an unequal air gap 800 that changes periodically along the circumferential direction is formed between the outer peripheral wall of the rotor and the inner peripheral wall of the stator. By cooperating with the ratio of θ1 and θ2, the magnetic field distribution in the air gap 800 of the motor 1 is further optimized. On the basis of ensuring the unchanged peak torque of the motor 1, the torque ripple of the motor 1 is significantly improved, the running vibration and noise of the motor 1 are reduced, and the user's comfort level is improved. Meanwhile, the iron losses of the stator and rotor of the motor 1 are also reduced to a certain extent, which is beneficial to improving the motor efficiency.

[0163] Meanwhile, in coordination with the selection of θ1 and θ2, the present application reasonably sets the relationship between H1 and H2 so that 0.12 ≤ (H1 - H2) / (H1 + H2) ≤ 0.33. In this way, not only the advantages of the integral circular design and the pure eccentric design of the rotor core 20 are taken into account, but also on the basis of not changing the average air gap 800 length of the motor 1 and ensuring that the peak torque of the motor 1 remains unchanged, the air gap 800 magnetic field can be effectively improved, the air gap 800 magnetic density and the sinusoidality of the back electromotive force waveform are increased, the harmonic proportion is reduced, and thus the torque ripple is reduced. Moreover, the vibration and noise of the motor 1 are significantly reduced, which is beneficial to improving the service performance and market competitiveness of the product.

[0164] Optionally, θ2 / θ1 = 1.7, θ2 / θ1 = 1.8, θ2 / θ1 = 1.9, θ2 / θ1 = 2, etc., which are not listed one by one here.

[0165] Optionally, (H1 - H2) / (H1 + H2) = 0.15, (H1 - H2) / (H1 + H2) = 0.18, (H1 - H2) / (H1 + H2) = 0.2, (H1 - H2) / (H1 + H2) = 0.25, (H1 - H2) / (H1 + H2) = 0.28, (H1 - H2) / (H1 + H2) = 0.3, etc., which are not listed one by one here.

[0166] In some embodiments, optionally, as Figure 1 and Figure 4 shown, the stator core 10 includes an annular yoke portion 110 and a plurality of tooth portions 120.

[0167] Any one of the plurality of tooth portions 120 is connected to the inner peripheral wall of the annular yoke portion 110.

[0168] The plurality of tooth portions 120 are arranged at intervals along the circumferential direction of the stator core 10.

[0169] The tooth portion 120 includes a tooth body 122 and a tooth tip 124.

[0170] The tooth body 122 is connected between the tooth tip 124 and the inner peripheral wall of the annular yoke portion 110.

[0171] Any adjacent two tooth portions 120 and the annular yoke portion 110 enclose a stator slot 130.

[0172] The tooth tip 124 is disposed opposite to the rotor core 20.

[0173] Among any adjacent two tooth portions 120, along the circumferential direction of the stator core 10, the side walls of the two tooth bodies 122 that are close to each other are respectively denoted as the first side wall 140 and the second side wall 150.

[0174] The first side wall 140 and the second side wall 150 are arranged in parallel.

[0175] In this embodiment, the stator core 10 includes an annular yoke 110 and a plurality of teeth 120 .

[0176] Any one of the plurality of teeth 120 is connected to the inner peripheral wall of the annular yoke 110 , and the plurality of teeth 120 are arranged at intervals along the circumferential direction of the stator core 10 .

[0177] Each of the multiple tooth sections 120 includes a tooth body 122 and a tooth shoe 124. The tooth body 122 is connected between the tooth shoe 124 and the inner circumferential wall of the annular yoke 110. Of any two adjacent tooth sections 120, one tooth section 120 is designated as a first tooth section, and the other tooth section 120 is designated as a second tooth section. Along the circumference of the stator core 10, the side wall of the first tooth section facing the second tooth section is designated as a first side wall 140, and the side wall of the second tooth section facing the first tooth section is designated as a second side wall 150. The first side wall 140 and the second side wall 150 are arranged in parallel.

[0178] The shape of the tooth body 122 is indirectly defined by the mating structure of the first side wall 140 and the second side wall 150. For example, the width of the tooth body 122 in the circumferential direction of the stator core 10 gradually decreases from the annular yoke 110 to the tooth portion 120. This satisfies the requirement for a parallel arrangement of the first and second side walls 140, 150. Optionally, both the first and second side walls 140, 150 are planar walls; alternatively, both the first and second side walls 140, 150 are curved walls.

[0179] The distance between the first sidewall 140 and the second sidewall 150 can affect the size of the stator slots 130 of the motor 1 and the saturation level of the teeth 120. To ensure a reasonable slot fill rate and current density of the motor 1, it is necessary to reasonably constrain the dimensions of the teeth 120 and stator slots 130 of the stator core 10 to ensure the performance of the motor 1.

[0180] In some embodiments, optionally, as Figure 4 As shown, along the circumferential direction of the stator core 10 , the width of the end portion of the tooth body 122 away from the annular yoke 110 is recorded as Wt, and the distance from the first side wall 140 to the second side wall 150 is recorded as Ws.

[0181] Among them, 0.95≤Wt / Ws≤1.45.

[0182] In this embodiment, the structure of the stator core 10 is further defined so that along the circumference of the stator core 10, the width of the end of the tooth body 122 away from the annular yoke 110 is recorded as Wt, and the distance from the first side wall 140 to the second side wall 150 is recorded as Ws, and the relationship between Wt and Ws is defined so as to satisfy 0.95≤Wt / Ws≤1.45.

[0183] The tooth top width of the tooth body 122 (the tooth top width refers to the width of the end of the tooth body 122 away from the annular yoke 110 along the circumference of the stator core 10) and the width of the stator slot 130 (the width of the stator slot 130 refers to the distance from the first side wall 140 to the second side wall 150) directly determine the size of the stator slot 130 of the motor 1 and the saturation degree of the tooth portion 120.

[0184] To ensure a reasonable slot fill rate and current density for motor 1, it is necessary to reasonably constrain the dimensions of the teeth 120 and stator slots 130 of motor 1. Excessively large tooth tip widths and insufficient stator slot 130 widths, or both, can lead to improper stator size design for motor 1, resulting in oversaturated and undersaturated regions in the magnetic flux density design. This can lead to high magnetic flux leakage in oversaturated regions, waste material in undersaturated regions, and insufficient cross-linking between the rotor and stator magnetic fields, preventing motor 1 from fully realizing its performance.

[0185] This results in low output torque, high harmonic content, poor back-EMF waveform, low motor efficiency, insufficient stator stiffness, and high vibration noise. This also increases the manufacturing cost of motor 1. To balance the cost of motor 1 with its electromagnetic performance, it is necessary to properly match the tooth tip width of motor 1 with the width of stator slot 130.

[0186] Setting the ratio of the tooth slot size parameters of motor 1 within the above range not only reduces the slot leakage flux of motor 1 while constraining the total area of stator slot 130 to remain unchanged, but also makes the parameter matching between tooth portion 120 and stator slot 130 more reasonable, and takes into account both the cost of motor 1 and the electromagnetic performance of motor 1, with uniform magnetic flux distribution, small leakage flux, high proportion of winding copper, and high material utilization rate of motor 1. While ensuring that motor 1 has a reasonable current density, the processing and manufacturing cost of motor 1 is not increased, and the output torque and efficiency of motor 1 are maximized. In addition, the stator core 10 has good stiffness, which is conducive to improving the vibration noise of motor 1. Without increasing material usage or volume envelope, the motor efficiency and peak torque and peak power output are maximized, which is conducive to improving the performance of the product and reducing the production cost of the product.

[0187] Optionally, Wt / Ws=1, Wt / Ws=1.1, Wt / Ws=1.2, Wt / Ws=1.3, and Wt / Ws=1.4, etc., which are not listed here one by one.

[0188] In some embodiments, optionally, as Figure 4 As shown, the annular yoke 110 is a structure of equal ring width.

[0189] The ring width of the annular yoke 110 is represented by Ys.

[0190] The outer diameter of the stator core 10 is denoted as Ds1.

[0191] The split ratio of the stator core 10 is denoted as k.

[0192] Among them, 0.13 ≤ Ys / (1 - k) / Ds1 ≤ 0.25, 0.65 ≤ k ≤ 0.79.

[0193] In this embodiment, the structure of the stator core 10 is further defined such that the annular yoke portion 110 has an equal ring width structure. The ring width of the annular yoke portion 110 is denoted as Ys, the outer diameter of the stator core 10 is denoted as Ds1, and the split ratio of the stator core 10 is denoted as k. Ys, Ds1, and k satisfy 0.13 ≤ Ys / (1 - k) / Ds1 ≤ 0.25, 0.65 ≤ k ≤ 0.79.

[0194] The multiple tooth portions 120 of the stator cooperate with the annular yoke portion 110, and a stator slot 130 is formed between two adjacent tooth portions 120 and the annular yoke portion 110. The distance between the bottom surface of the stator slot 130 and the outer peripheral wall of the annular yoke portion 110 forms the ring width of the annular yoke portion 110. The ring width of the annular yoke portion 110 directly determines the magnetic density of the annular yoke portion 110, the size of the stator slot 130, the torque output of the motor 1, and the stator stiffness. In order to optimize the magnetic density of the annular yoke portion 110 of the motor 1 and the space of the stator slot 130 on the premise of meeting the torque output of the motor 1 and the stiffness of the stator, the efficiency of the motor 1 can be improved.

[0195] It is necessary to adjust the ring width of the annular yoke portion 110, and the size of the ring width of the annular yoke portion 110 is restricted by the size space of the stator itself. That is, it is restricted by the inner diameter of the stator core 10 and the outer diameter Ds1 of the stator core 10. The stator split ratio k is equal to the ratio of the inner diameter of the stator core 10 to the outer diameter of the stator core 10. Therefore, by reasonably setting the relationship between Ys, k, and Ds1 so that 0.13 ≤ Ys / (1 - k) / Ds1 ≤ 0.25, 0.65 ≤ k ≤ 0.79, the radial proportion of the stator slot 130 and the annular yoke portion 110 can be reasonably allocated under the limited stator size. On the premise of taking into account the cost of the motor 1 and the electromagnetic performance of the motor 1, the output torque and efficiency of the motor 1 are maximized, and the stator core 10 has good stiffness, which is beneficial to improving the vibration and noise of the motor 1.

[0196] In some embodiments, optionally, as Figure 1 and Figure 4 shown, the motor 1 further includes a plurality of winding portions 900.

[0197] Any one of the plurality of winding portions 900 is disposed in a stator slot 130.

[0198] The winding portion 900 includes a plurality of winding segments 910.

[0199] A plurality of winding segments 910 are arranged along the direction from the annular yoke portion 110 to the tooth portion 120.

[0200] The length of the winding segment 910 in the circumferential direction of the stator core 10 is denoted as L1.

[0201] The length of the winding segment 910 in the direction from the tooth portion 120 to the annular yoke portion 110 is denoted as L2.

[0202] Wherein, 1.2 ≤ L1 / L2 ≤ 2.5.

[0203] In this embodiment, the stator further includes a plurality of winding portions 900, and any one of the plurality of winding portions 900 is matched with a stator slot 130. Specifically, each winding portion 900 is disposed in a stator slot 130.

[0204] The winding portion 900 includes a plurality of winding segments 910, and the plurality of winding segments 910 are arranged along the direction from the annular yoke portion 110 to the tooth portion 120.

[0205] The winding segment 910 has a flat wire structure. Specifically, along the circumferential direction of the stator, the length of the winding segment 910 is denoted as L1, and along the direction from the tooth portion 120 to the annular yoke portion 110, the length of the winding segment 910 is denoted as L2. And the relationship between L1 and L2 is defined to satisfy 1.2 ≤ L1 / L2 ≤ 2.5.

[0206] A plurality of winding segments 910 are provided in the stator slot 130, and the plurality of winding segments 910 are arranged along the direction from the annular yoke portion 110 to the tooth portion 120. This application defines the relationship between L1 and L2. Especially in a flat wire motor, since the size of the flat wire-shaped winding segment 910 is relatively large compared with that of the multi-strand parallel round wire-shaped winding segment in terms of the single-turn conductor size area. When alternating current is applied to the motor 1, due to the different leakage magnetic turn linkages of each part of the cross-section of the winding portion 900 in the slot height direction (i.e., the direction from the bottom of the stator slot 130 to the slot opening), induced electromotive forces of different magnitudes will be generated, thereby generating eddy currents, bringing additional eddy current losses, and causing the motor efficiency to decrease and the temperature rise to increase. Therefore, it is necessary to reduce the size of the flat wire-shaped winding segment 910 in the direction from the bottom of the stator slot 130 to the slot opening as much as possible, and increase the ratio of L1 to L2 of the flat wire-shaped winding segment 910 as much as possible, so that the ratio is within the range of 1.2 to 2.5.

[0207] If L1 / L2 > 2.5, the processing difficulty and manufacturing cost of the product will increase. Therefore, this application defines that the value of L1 / L2 is within the range of 1.2 to 2.5. Not only is the manufacturing and winding process difficulty of the winding portion 900 low, but the eddy current loss on the winding portion 900 is also relatively small, which is beneficial to improving the efficiency of the motor 1.

[0208] In some embodiments, optionally, as Figure 4As shown, the number of stator slots 130 is denoted as s, and the inner diameter of the stator core 10 is denoted as Ds2, where 0.47×π×(Ds2 / s) ≤ Wt ≤ 1.45×Ws.

[0209] In this embodiment, in order to balance the cost of the motor 1 and the electromagnetic performance of the motor 1, it is necessary to perform a reasonable numerical matching on the tooth portion 120 of the stator core 10 and the structure of the stator slots 130. So that Wt, Ws, s, and Ds2 satisfy 0.47×π×(Ds2 / s) ≤ Wt ≤ 1.45×Ws. In this way, while keeping the total area of the stator slots 130 unchanged, the slot leakage magnetic flux of the motor 1 can be reduced, the parameter matching between the tooth portion 120 and the stator slots 130 can be made more reasonable, the production cost of the motor 1 and the electromagnetic performance of the motor 1 are balanced, the magnetic flux density distribution is uniform, the leakage magnetic flux is small, which is beneficial to increasing the copper ratio of the winding and improving the material utilization rate of the motor 1. While ensuring that the motor 1 has a reasonable current density, without increasing the manufacturing cost of the motor 1, maximizing the output torque and efficiency of the motor 1. And the stator core 10 has good stiffness, which is beneficial to improving the vibration and noise of the motor 1. That is to say, while not increasing the production cost of the motor 1, the efficiency, peak torque, and peak power output of the motor 1 are balanced.

[0210] In some embodiments, optionally, as Figure 3 shown, the part of the outer peripheral wall of the rotor core 20 opposite to the magnetic pole portion 300 includes an intermediate arc segment 510, a first side arc segment 520, and a second side arc segment 530.

[0211] The intermediate arc segment 510 is located between the first side arc segment 520 and the second side arc segment 530.

[0212] The intermediate arc segment 510 is disposed opposite to the first magnetic slot group 310.

[0213] The radius corresponding to any one of the first side arc segment 520 and the second side arc segment 530 is smaller than the radius corresponding to the intermediate arc segment 510.

[0214] The value of the gap between one of the first side arc segment 520 and the second side arc segment 530 and the inner peripheral wall of the stator core 10 is the maximum value of the air gap 800.

[0215] The value of the gap between the intermediate arc segment 510 and the inner peripheral wall of the stator core 10 is the minimum value of the air gap 800.

[0216] In this embodiment, the structure of the rotor core 20 is further defined such that the portion of the outer peripheral wall of the rotor core 20 opposite to the magnetic pole portion 300 includes an intermediate arc segment 510, a first side arc segment 520, and a second side arc segment 530. The first side arc segment 520 is located on the first side of the intermediate arc segment 510, and the second side arc segment 530 is located on the second side of the intermediate arc segment 510. That is, the intermediate arc segment 510 is located between the first side arc segment 520 and the second side arc segment 530. Among them, the intermediate arc segment 510 is disposed opposite to the first magnetic slot group 310.

[0217] Among them, the radius corresponding to the first side arc segment 520 is smaller than the radius corresponding to the intermediate arc segment 510, and the radius corresponding to the second side arc segment 530 is smaller than the radius corresponding to the intermediate arc segment 510.

[0218] It can be understood that the outer peripheral wall of the rotor core 20 includes an outer peripheral segment on the axial end face, and the outer peripheral segment is a closed curve.

[0219] The outer peripheral wall of the rotor core 20 includes a plurality of sequentially connected arc segment groups, and one arc segment group corresponds to one magnetic pole portion 300. It should be noted that the number of arc segment groups and the number of magnetic pole portions 300 are both equal to the pole pair number p of the motor 1.

[0220] Let each arc segment group include at least an intermediate arc segment 510, a first side arc segment 520, and a second side arc segment 530. For the motor 1, an unequal air gap 800 that changes periodically in the circumferential direction can be formed between the outer peripheral wall of the rotor and the inner peripheral wall of the stator. Thus, an alternation between the first side arc segment 520, the intermediate arc segment 510, and the second side arc segment 530 is formed on the outer peripheral wall of the rotor core 20, which can make the operation of the motor 1 more stable. At the same time, the magnetic field distribution of the rotor is optimized, the armature reaction of the direct and quadrature axes is effectively weakened. Without changing the peak torque of the motor 1, the torque ripple of the motor 1 is significantly improved, and the running vibration noise of the motor 1 is reduced. At the same time, the iron losses of the stator and rotor of the motor 1 are also reduced to a certain extent, which is beneficial to improving the efficiency of the motor 1.

[0221] Further, the outer peripheral wall of the rotor core 20 body includes an intermediate arc segment 510, a first side arc segment 520, and a second side arc segment 530. Among them, the radius corresponding to any one of the first side arc segment 520 and the second side arc segment 530 is smaller than the radius corresponding to the intermediate arc segment 510. A maximum air gap H1 is formed between the first side arc segment 520 or the second side arc segment 530 and the inner peripheral wall of the stator core 10, and a minimum air gap H2 is formed between the intermediate arc segment 510 and the inner peripheral wall of the stator core 10.

[0222] In some embodiments, optionally, as Figure 5As shown, in the two magnet slots 330 of the first magnet slot group 310, the permanent magnet segment 336 of one magnet slot 330 has a third side wall 340, and the permanent magnet segment 336 of the other magnet slot 330 has a fourth side wall 350.

[0223] Either the third side wall 340 or the fourth side wall 350 is arranged facing the outer peripheral wall of the rotor core 20.

[0224] The third side wall 340 and the fourth side wall 350 form an included angle b1.

[0225] In the two magnet slots 330 of the second magnet slot group 320, the permanent magnet segment 336 of one magnet slot 330 has a fifth side wall 360, and the permanent magnet segment 336 of the other magnet slot 330 has a sixth side wall 370.

[0226] Either the fifth side wall 360 or the sixth side wall 370 is arranged facing the outer peripheral wall of the rotor core 20.

[0227] The fifth side wall 360 and the sixth side wall 370 form an included angle b2.

[0228] Wherein, 0° ≤ b1 - b2 ≤ 50°.

[0229] In this embodiment, in the two magnet slots 330 of the first magnet slot group 310, the permanent magnet segment 336 of one magnet slot 330 has a third side wall 340, and the permanent magnet segment 336 of the other magnet slot 330 has a fourth side wall 350. In the two magnet slots 330 of the second magnet slot group 320, the permanent magnet segment 336 of one magnet slot 330 has a fifth side wall 360, and the permanent magnet segment 336 of the other magnet slot 330 has a sixth side wall 370. Either the third side wall 340, the fourth side wall 350, the fifth side wall 360 or the sixth side wall 370 is arranged facing the outer peripheral wall of the rotor core 20.

[0230] The third side wall 340 and the fourth side wall 350 form an included angle b1, and the fifth side wall 360 and the sixth side wall 370 form an included angle b2.

[0231] The included angle b1 is called the outer magnetic pole included angle b1, and the included angle b2 is called the inner magnetic pole included angle b2.

[0232] In a permanent magnet synchronous motor, the values of the pole arc angle θ1 of the outer V-shaped pole structure and the pole arc angle θ2 of the inner V-shaped pole structure have a greater impact on the reluctance of the direct-axis magnetic circuit of the motor 1. That is, it has a greater impact on the inductance of the direct-axis magnetic circuit. The values of the outer pole angle b1 and the inner pole angle b2 have a greater impact on the reluctance of the quadrature-axis magnetic circuit of the motor 1. That is, it has a greater impact on the inductance of the quadrature-axis magnetic circuit (the smaller the reluctance, the larger the inductance; conversely, the larger the reluctance, the smaller the inductance). The saliency ratio of the motor 1 is the ratio of the quadrature-axis inductance to the direct-axis inductance. The torque of the motor 1 is the reluctance torque (the electromagnetic torque component generated by the difference between the quadrature-axis and direct-axis inductances of the permanent magnet synchronous motor) plus the permanent magnet torque (the electromagnetic torque component generated by the permanent magnet 22 of the permanent magnet synchronous motor). There is a positive numerical relationship between the amount of the permanent magnet 22 and the permanent magnet torque.

[0233] In this application, by making the above numerical matching for the ratio of the pole arc angle θ1 of the outer V-shaped pole structure to the pole arc angle θ2 of the inner V-shaped pole structure, and the ratio of the outer pole angle b1 to the inner pole angle b2, the ratio of the quadrature-axis inductance to the direct-axis inductance of the motor 1 can be increased, and the saliency ratio can be improved. After the saliency ratio is improved, the utilization rate of the reluctance torque of the motor 1 is also improved. When the motor 1 torque of the same magnitude is output, the permanent magnet torque can be smaller. Thus, the amount of the permanent magnet 22 can be reduced, thereby reducing the cost.

[0234] On the other hand, the resultant magnetomotive force of a pole part 300 is obtained by superimposing the magnetomotive forces generated by the permanent magnets 22 in the first magnetic slot group 310 and the permanent magnets 22 in the second magnetic slot group 320 (abbreviated as the outer magnetomotive force and the inner magnetomotive force). The resultant magnetomotive force is affected not only by the outer magnetomotive force or the inner magnetomotive force alone, but also by the superposition result of the two.

[0235] The waveforms of the resultant magnetomotive force, the outer magnetomotive force, and the inner magnetomotive force all include a fundamental wave and harmonics. The fundamental wave and harmonics in the outer magnetomotive force are related to the pole arc angle θ1 of the outer V-shaped pole structure and the outer pole angle b1, and the fundamental wave and harmonics in the inner magnetomotive force are related to the pole arc angle θ2 of the inner V-shaped pole structure and the inner pole angle b2.

[0236] In this application, by simultaneously making the above numerical matching for the pole arc angle θ1 of the outer V-shaped pole structure, the outer pole angle b1, the pole arc angle θ2 of the inner V-shaped pole structure, and the inner pole angle b2, the waveform of the resultant magnetomotive force can be optimized, the harmonic components in the waveform of the resultant magnetomotive force can be effectively suppressed, the sinusoidality of the air-gap 800 magnetic field waveform can be improved, thereby reducing the cogging torque and torque ripple of the permanent magnet synchronous motor, and reducing the vibration and noise of the motor 1.

[0237] Moreover, since the outer pole angle is not equal to the inner pole angle, more combinations can be generated when the outer pole angle and the inner pole angle are numerically matched. Thus, the waveform of the resultant magnetomotive force can be more flexibly optimized to meet the product requirements.

[0238] In some embodiments, optionally, as Figure 1 , Figure 2 , Figure 6 and Figure 7 shown, the rotor core 20 is provided with a plurality of weight-reducing holes 600.

[0239] The plurality of weight-reducing holes 600 are arranged at intervals.

[0240] The weight-reducing holes 600 are located on the magnetic pole center line or the inter-pole center line of the rotor core 20.

[0241] The number of the weight-reducing holes 600 is 2×N1×p, where N1 is a positive integer and p is the number of pole pairs of the motor.

[0242] In this embodiment, the structure of the rotor core 20 is such that the rotor core 20 is provided with a plurality of weight-reducing holes 600, and the plurality of weight-reducing holes 600 are arranged at intervals. Specifically, the plurality of weight-reducing holes 600 are arranged at intervals along the circumferential direction of the shaft hole 200.

[0243] On the one hand, an overweight rotor mass will increase the centrifugal force load of the rotor, reduce the fatigue life of the rotor core 20, and increase the production cost. Therefore, it is necessary to use the weight-reducing holes 600 to reduce the weight of the rotor core 20. On the other hand, for the motor 1 using rotor oil cooling, oil holes need to be arranged on its rotor core 20 as oil cooling channels to cool the rotor core 20. The weight-reducing holes 600 can be used as oil holes, reduce the mass of the rotor core 20, and can also be used as positioning holes to assist in the installation and positioning of the rotor core 20. Therefore, a plurality of weight-reducing holes 600 are provided on the rotor core 20 in this application.

[0244] Further limit the number and distribution position of the weight-reducing holes 600.

[0245] The weight-reducing holes 600 are located on the magnetic pole center line or the inter-pole center line of the rotor core 20. For example, any one of the plurality of weight-reducing holes 600 is located on the magnetic pole center line of the rotor core 20. For another example, any one of the plurality of weight-reducing holes 600 is located on the inter-pole center line of the rotor core 20. For another example, a part of the plurality of weight-reducing holes 600 is located on the magnetic pole center line of the rotor core 20, and another part of the plurality of weight-reducing holes 600 is located on the inter-pole center line of the rotor core 20.

[0246] The number of the weight-reducing holes 600 is 2×N1×p, where N1 is a positive integer and p is the number of pole pairs of the motor. For example, the number of the weight-reducing holes 600 includes 4, 6, 8, 12, 16 or 20, etc., and will not be listed one by one here.

[0247] That is to say, multiple weight-reducing holes 600 are in the same circumferential region of the rotor core 20. This setting makes the overall structure of the rotor core 20 more uniform, and can ensure the balance and consistency of the force.

[0248] At the same time, for a rotor core 20, it has a magnetic pole center line and an inter-pole center line. Among them, the line connecting the centers of the magnetic pole part 300 and the shaft hole 200 forms the magnetic pole center line, simply referred to as the d-axis. The angular bisector of two adjacent magnetic pole center lines is the inter-pole center line, and the inter-pole center line is also called the adjacent magnetic pole center line, simply referred to as the q-axis.

[0249] The weight-reducing holes 600 are located on the magnetic pole center line or the inter-pole center line of the rotor core 20. On the premise of ensuring that the performance of the motor 1 is not affected, the setting of the weight-reducing holes 600 can reduce the moment of inertia and reduce the overall weight of the motor 1.

[0250] In some embodiments, optionally, as Figure 6 shown, the minimum distance from multiple weight-reducing holes 600 to the outer peripheral wall of the rotor core 20 is denoted as L3.

[0251] The radius of the shaft hole 200 is denoted as R1.

[0252] The radius of the rotor core 20 is denoted as R2.

[0253] Among them, 0.45 ≤ L3 / (R2 - R1) ≤ 0.77.

[0254] In this embodiment, for the structure of the rotor core 20, among multiple weight-reducing holes 600, the weight-reducing hole 600 with the minimum distance to the outer peripheral wall of the rotor core 20 is denoted as the weight-reducing reference hole, and the minimum distance from the weight-reducing reference hole to the outer peripheral wall of the rotor core 20 is denoted as L3. The radius of the shaft hole 200 is denoted as R1. The radius of the rotor core 20 is denoted as R2. L3, R1, and R2 satisfy 0.45 ≤ L3 / (R2 - R1) ≤ 0.77. For different outer diameters of the rotating shaft and different outer diameters of the rotor core 20, the positions of the weight-reducing holes 600 are also different. If the weight-reducing holes 600 are too close to the position of the rotating shaft, it will increase the stress level at the inner side position of the shaft hole 200. If the weight-reducing holes 600 are too close to the outer peripheral wall of the rotor core 20, it will affect the stress on the outer circumferential side of the rotor core 20 and the magnetic circuit of the motor 1, and affect the torque and strength performance of the motor 1.

[0255] The minimum distance L3 from the plurality of weight-reducing holes 600 to the outer peripheral wall of the rotor core 20, the radius R1 of the shaft hole 200, and the radius R2 of the rotor core 20 are limited within the above ranges, which can not only meet the weight-reducing requirements but also meet the performance requirements of the motor 1, and can enable the rotor core 20 to be uniformly deformed and stressed under the centrifugal force load to relieve the stress concentration problem on the rotor core 20. At the same time, the distribution of the weight-reducing holes 600 has no influence on the electromagnetic performance of the rotor core 20. In addition, the rotor core 20 of the present application can simultaneously meet the design requirements of rotors in multiple power segments including water cooling and oil cooling, and has the characteristics of platform design.

[0256] In some embodiments, optionally, as Figure 6 shown, along the inner end 332 to the outer end 334, the width of the permanent magnet segment 336 of the first magnetic slot group 310 is denoted as W1, and the width of the permanent magnet segment 336 of the second magnetic slot group 320 is denoted as W2.

[0257] Wherein, 0.17 ≤ (W2 - W1) / (W2 + W1) ≤ 0.49.

[0258] In this embodiment, the structure of the magnetic pole portion 300 is further defined.

[0259] Any one of the first magnetic slot group 310 and the second magnetic slot group 320 includes two magnet slots 330, the magnet slots 330 axially penetrate the rotor core 20 along the axial direction of the rotor core 20, and the magnet slots 330 are used to accommodate the permanent magnets 22 of the rotor.

[0260] Any one of the plurality of magnet slots 330 includes a permanent magnet segment 336 and a magnetic isolation segment 338, and the permanent magnet segment 336 and the magnetic isolation segment 338 are communicated with each other. Specifically, the permanent magnet segment 336 is used to accommodate the permanent magnet 22 of the rotor, the permanent magnet 22 is embedded in the permanent magnet segment 336, and no permanent magnet 22 is provided in the magnetic isolation segment 338, that is, the magnetic isolation segment 338 is vacant. The magnetic isolation segment 338 is connected to one side of the permanent magnet segment 336, or the number of the magnetic isolation segments 338 is two, and the permanent magnet segment 336 is connected between the two magnetic isolation segments 338.

[0261] Wherein, the magnetic pole portion 300 includes a first magnetic slot group 310 and a second magnetic slot group 320 in a "V" shape. The magnetic fluxes generated by the permanent magnets 22 in the first magnetic slot group 310 and the second magnetic slot group 320 act together (hereinafter, the magnetic flux generated by the first magnetic slot group 310 is simply referred to as the outer magnetic flux, and the magnetic flux generated by the second magnetic slot group 320 is simply referred to as the inner magnetic flux) and are superimposed. The synthesized magnetic flux is affected not only by the outer magnetic flux or the inner magnetic flux alone, but also by the superposition result of the two. Therefore, there is an optimal width ratio between the two.

[0262] By reasonably setting the cooperation structure of the permanent magnet segments 336 of the first magnetic slot group 310 and the permanent magnet segments 336 of the second magnetic slot group 320, along the inner end 332 to the outer end 334, the width of the permanent magnet segment 336 of the first magnetic slot group 310 is denoted as W1, and the width of the permanent magnet segment 336 of the second magnetic slot group 320 is denoted as W2, where 0.17 ≤ (W2 - W1) / (W2 + W1) ≤ 0.49. Under the optimal width ratio, the synthetic magnetic chain can be reasonably distributed to the d-axis and q-axis of the rotor core 20 to jointly generate the output torque. In this way, without increasing the material cost or volume envelope of the motor 1, the peak torque and peak output power of the motor 1 can be significantly improved. It not only improves the utilization rate of the permanent magnet 22 of the rotor but also enables a higher torque and power density output.

[0263] Optionally, (W2 - W1) / (W2 + W1) = 0.2, (W2 - W1) / (W2 + W1) = 0.25, (W2 - W1) / (W2 + W1) = 0.28, (W2 - W1) / (W2 + W1) = 0.3, (W2 - W1) / (W2 + W1) = 0.32, (W2 - W1) / (W2 + W1) = 0.35, (W2 - W1) / (W2 + W1) = 0.4, and (W2 - W1) / (W2 + W1) = 0.45, etc., which are not listed one by one here.

[0264] In some embodiments, optionally, along the axial direction of the rotor core 20, the rotor core 20 includes a plurality of core groups 700.

[0265] The core group 700 includes a plurality of stacked core segments 710.

[0266] Any two adjacent core segments 710 in the core group 700 are arranged in a circumferentially offset manner on the rotor core 20.

[0267] The offset angle is denoted as θ.

[0268] The total number of the core segments 710 of the plurality of core groups 700 is denoted as n, and n ≥ 2.

[0269] The number of the stator slots 130 is denoted as Z.

[0270] The number of pole pairs of the motor 1 is denoted as p.

[0271] θ = θ0 + Δθ, θ0 = 360° / (n × Nc), Nc = LCM(Z, 2 × p), 0° ≤ Δθ ≤ θ0.

[0272] In this embodiment, along the axial direction of the rotor core 20, the rotor core 20 includes a plurality of core groups 700. Each core group 700 includes a plurality of core segments 710. Any two adjacent core segments 710 in the core group 700 are arranged with a circumferential misalignment in the rotor core 20. That is, the rotor core 20 is assembled in a segmented skew pole manner, that is, at least two adjacent core segments 710 are arranged with a circumferential misalignment in the rotor core 20. The misalignment angle is θ, θ = θ0 + Δθ, θ0 = 360° / (n×Nc), where n is the total number of core segments 710 of the plurality of core groups 700, and n is a natural number greater than or equal to 2. Nc = LCM(Z, 2×p), Z is the number of stator slots 130, p is the number of pole pairs of the motor 1, and 0° ≤ Δθ ≤ θ0. Since the permanent magnets 22 in the motor 1 do not change the magnetic strength according to the position and state of the motor 1, during the circumferential operation, the magnetic poles of the permanent magnets 22 will generate different attractive forces on the stator slots 130 and the teeth 120 of the stator. The different attractive forces will cause torque fluctuations when the rotor rotates, and this fluctuation will cause vibration and noise during the operation of the motor 1.

[0273] Especially for high-power motors 1 such as vehicle-mounted permanent magnet synchronous motors, the vibration and noise caused by this reason are more obvious.

[0274] However, the optimization combination effect of the structural parameters in the motor 1 has a limited effect on improving the air-gap 800 magnetic field waveform. Especially the tooth harmonics, which are the main source of vibration and noise of the motor 1. Therefore, it is also necessary to combine the segmented skew pole of the rotor to further weaken the harmonic content. The segmented misaligned poles of the rotor can reduce the cogging torque and torque ripple, thereby reducing electromagnetic vibration. In other words, by dividing the rotor core 20 into a plurality of core groups 700 and making there be a relative rotation angle between different core segments 710 in the core group 700, the specific harmonic content in the motor 1 can be effectively suppressed, the torque ripple and cogging torque of the motor 1 can be improved, and thus the vibration and noise of the motor 1 can be reduced.

[0275] The segmented skew pole can, while ensuring the electromagnetic torque of the motor 1, maximize the reduction of the end leakage flux of the permanent magnets 22, improve the utilization rate of the permanent magnets 22, weaken the cogging torque, and reduce the torque ripple of the motor 1. At the same time, it can improve the air-gap 800 magnetic field distribution, reduce the distortion rate of the air-gap 800 magnetic field, and improve the noise and vibration performance of the motor 1.

[0276] A power system according to some other embodiments of the present application includes: the motor 1 in any of the above embodiments.

[0277] The power system provided by the present application includes the motor 1 in any of the embodiments, and therefore has all the beneficial effects of the above motor 1, which will not be described one by one here.

[0278] Optionally, the power system includes a motor 1, a controller, and a speed reducer. The controller is electrically connected to the motor 1 and the speed reducer, and the controller controls the operation of the motor 1 and the speed reducer. The power system can meet the usage requirements of torque and power for the vehicle to move forward.

[0279] A vehicle according to some further embodiments of the present application includes: the motor 1 in any of the above embodiments, or the power system in the above embodiments.

[0280] The vehicle provided by the present application includes the motor 1 in the first aspect or the power system in the second aspect, and thus has all the beneficial effects of the above motor 1 or power system, which will not be elaborated one by one here.

[0281] It should be noted that the vehicle can be a new energy vehicle. New energy vehicles include pure electric vehicles, range-extended electric vehicles, hybrid electric vehicles, fuel cell electric vehicles, hydrogen engine vehicles, etc.

[0282] Optionally, as Figure 12 shown, in the motor 1 with 48 slots and 8 poles as an example, the data curve graph of the output torque and torque ripple of the motor 1 changing with the ratio of θ2 / θ1. Among them, B1 represents the output torque, and B2 represents the torque ripple. It can be seen from Figure 12 that the ratio of θ2 / θ1 not only affects the output torque of the motor 1 but also affects the torque ripple of the motor 1.

[0283] When θ2 and θ1 satisfy 1.64 ≤ θ2 / θ1 ≤ 2.1, the output torque of the motor 1 is relatively high and the torque ripple is relatively low. That is, for the motor 1 with the same torque design target, by using the pole arc angle θ1 of the outer-layer V-shaped magnetic pole structure and the pole arc angle θ2 of the inner-layer V-shaped magnetic pole structure in the present application, the motor 1 has excellent torque output quality, can further reduce the volume of the motor 1, lower the cost of the motor 1, and at the same time, the torque ripple of the motor 1 is low, which is beneficial to improving the vibration and noise problems of the motor 1.

[0284] As Figure 13 shown, in the motor 1 with 48 slots and 8 poles as an example, the curve data graph of the torque ripple of the motor 1 changing with (H1 - H2) / (H1 + H2). It can be seen from Figure 13 that for the motor 1 satisfying the above conditions, that is, when H1 and H2 satisfy 0.12 ≤ (H1 - H2) / (H1 + H2) ≤ 0.33, the torque ripple of the motor 1 is the lowest and the output torque quality is the highest.

[0285] As Figure 4As shown, along the circumferential direction of the stator core 10, the width of the end of the tooth body 122 facing away from the annular yoke portion 110 is denoted as Wt, and the distance from the first side wall 140 to the second side wall 150 is denoted as Ws. Wt and Ws satisfy 0.95 ≤ Wt / Ws ≤ 1.45.

[0286] The width Wt of the end of the tooth body 122 facing away from the annular yoke portion 110 can be referred to as the tooth tip width of the tooth body 122. The distance Ws from the first side wall 140 to the second side wall 150 can be referred to as the width of the stator slot 130.

[0287] The tooth tip width of the tooth body 122 and the width of the stator slot 130 directly determine the size of the stator slot 130 of the motor 1 and the saturation degree of the tooth portion 120. In order to ensure a reasonable slot fill factor and current density of the motor 1, it is necessary to reasonably constrain the sizes of the tooth portion 120 and the stator slot 130 of the motor 1.

[0288] An overly large tooth tip width and an overly small width of the stator slot 130, or an overly small tooth tip width and an overly large width of the stator slot, will result in an unreasonable design of the stator size of the motor 1, with oversaturated and undersaturated regions in the magnetic flux density design. In the oversaturated region of the magnetic flux density, there is a large magnetic leakage, and in the undersaturated region of the magnetic flux density, there is material waste, resulting in insufficient cross-linking between the rotor magnetic field and the stator magnetic field, and the performance of the motor 1 not being fully exerted. At the same time, it leads to a low output torque of the motor 1, a large harmonic content in the motor 1, a poor back electromotive force waveform, a low efficiency of the motor 1, insufficient stiffness of the stator of the motor 1, and a large vibration and noise. At the same time, it leads to an increase in the manufacturing cost of the motor 1. In order to balance the cost of the motor 1 and the electromagnetic performance of the motor 1, it is necessary to reasonably match the numerical values of the tooth portion 120 and the stator slot 130 of the motor 1.

[0289] Setting the ratio of the tooth-slot size parameters of the motor 1 within the above range not only realizes reducing the slot leakage magnetic of the motor 1 while constraining the total area of the stator slot 130 to remain unchanged, making the parameter matching between the tooth portion 120 and the stator slot 130 more reasonable, balancing the cost of the motor 1 and the electromagnetic performance of the motor 1, with a uniform magnetic flux density distribution, small magnetic leakage, a high copper occupancy ratio of the winding, and a high material utilization rate of the motor 1. While ensuring that the motor 1 has a reasonable current density, it does not increase the processing and manufacturing cost of the motor 1, maximizing the output torque and efficiency of the motor 1, and having good stiffness of the stator punching sheet, which is beneficial to improving the vibration and noise of the motor 1. Without the need to increase the material usage or volume envelope, it balances the motor efficiency and maximizes the peak torque and peak power output, which is beneficial to cost savings.

[0290] As Figure 14 shown, taking the 8-pole 48-slot motor 1 as an example, Figure 14 shows the changes in the total motor loss and motor efficiency at the rated speed and torque operating point with the change of Wt / Ws. Among them, B3 represents the total motor loss, and B4 represents the motor efficiency. FromFigure 14 It can be seen that when 0.95 ≤ Wt / Ws ≤ 1.45 is satisfied between Wt and Ws, the total loss of the motor 1 is relatively minimized, and the output efficiency of the motor 1 is the highest, which is beneficial to improving the cruising range of the electric vehicle.

[0291] As Figure 4 shown, the annular yoke 110 has an equal ring width structure. The ring width Ys of the annular yoke 110, the outer diameter Ds1 of the stator core 10, and the split ratio of the stator core 10 are denoted as k, and 0.13 ≤ Ys / (1 - k) / Ds1 ≤ 0.25, 0.65 ≤ k ≤ 0.79. The multiple tooth portions 120 of the stator core cooperate with the annular yoke 110, and a stator slot 130 is formed between two adjacent tooth portions 120 and the annular yoke 110. An air gap 800 is formed between the bottom surface of the stator slot 130 and the outer peripheral wall of the annular yoke 110. The ring width of the annular yoke 110 directly determines the magnetic density of the annular yoke 110, the size of the stator slot 130, the torque output of the motor 1, and the stator stiffness. In order to optimize the magnetic density of the annular yoke 110 of the motor 1 and the space of the stator slot 130, and improve the efficiency of the motor 1 on the premise of meeting the torque output and stator stiffness of the motor 1, it is necessary to adjust the ring width of the annular yoke 110 of the motor 1. The size of the ring width of the annular yoke 110 is restricted by the size space of the stator itself, that is, restricted by the inner diameter of the stator core 10 and the outer diameter Ds1 of the stator core 10. The stator split ratio k is equal to the ratio of the inner diameter of the stator core 10 to the outer diameter of the stator core 10. Therefore, by reasonably setting the relationship between Ys, k, and Ds1 so that 0.13 ≤ Ys / (1 - k) / Ds1 ≤ 0.25, 0.65 ≤ k ≤ 0.79, the radial proportion of the stator slot 130 and the annular yoke 110 can be reasonably allocated under the limited stator size, maximizing the output torque and efficiency of the motor 1 on the premise of taking into account the cost of the motor 1 and the electromagnetic performance of the motor 1, and the stator core 10 has good stiffness, which is beneficial to improving the vibration and noise of the motor 1.

[0292] As Figure 15 shown, in the motor 1 with 48 slots and 8 poles as an example, the peak torque of the motor 1 and the total motor loss change with the change of the Ys / (1 - k) / Ds1 ratio. Exemplarily, k = 0.69, where B5 represents the peak torque and B6 represents the total motor loss. It can be seen from the figure that when Ys, k, and Ds1 satisfy 0.13 ≤ Ys / (1 - k) / Ds1 ≤ 0.25, the peak torque output of the motor 1 is relatively high, and the total motor loss is relatively minimized. Under the condition that the peak output performance of the motor 1 can be satisfied, the motor efficiency is improved, the short-time operation time of the peak working condition of the motor 1 is increased, and the electric vehicle has good acceleration, climbing, and cruising performance.

[0293] As Figure 5As shown, the magnetic pole portion 300 includes a first magnetic slot group 310 and a second magnetic slot group 320.

[0294] In the first magnetic slot group 310, the inner ends 332 of the two magnet slots 330 are close to each other, and the outer ends 334 of the two magnet slots 330 are far from each other. That is, the two magnet slots 330 are arranged in a "V" shape.

[0295] In the second magnetic slot group 320, the inner ends 332 of the two magnet slots 330 are close to each other, and the outer ends 334 of the two magnet slots 330 are far from each other. That is, the two magnet slots 330 are arranged in a "V" shape.

[0296] In the magnet slot 330 of the first magnetic slot group 310, the connection point between the side of the permanent magnet segment 336 facing away from the shaft hole 200 and one magnetic isolation segment 338 is denoted as the first vertex A1, and the connection point between the side of the permanent magnet segment 336 facing away from the shaft hole 200 and the other magnetic isolation segment 338 is denoted as the second vertex A2. The first radial extension line 410 passes through the center of the shaft hole 200, and the first radial extension line 410 intersects or is tangent to the first vertex. The second radial extension line 420 passes through the center of the shaft hole 200, and the second radial extension line 420 intersects or is tangent to the second vertex.

[0297] In the magnet slot 330 of the second magnetic slot group 320, the connection point between the side of the permanent magnet segment 336 facing away from the shaft hole 200 and one magnetic isolation segment 338 is denoted as the third vertex A3, and the connection point between the side of the permanent magnet segment 336 facing away from the shaft hole 200 and the other magnetic isolation segment 338 is denoted as the fourth vertex A4. The third radial extension line 430 passes through the center of the shaft hole 200, and the third radial extension line 430 intersects or is tangent to the third vertex. The fourth radial extension line 440 passes through the center of the shaft hole 200, and the fourth radial extension line 440 intersects or is tangent to the fourth vertex.

[0298] The included angle formed by the first radial extension line 410 and the second radial extension line 420 is denoted as θ1, and the included angle formed by the third radial extension line 430 and the fourth radial extension line 440 is denoted as θ2, where 1.64 ≤ θ2 / θ1 ≤ 2.1.

[0299] In the two magnet slots 330 of the first magnetic slot group 310, the permanent magnet segment 336 of one magnet slot 330 has a third side wall 340, and the permanent magnet segment 336 of the other magnet slot 330 has a fourth side wall 350. In the two magnet slots 330 of the second magnetic slot group 320, the permanent magnet segment 336 of one magnet slot 330 has a fifth side wall 360, and the permanent magnet segment 336 of the other magnet slot 330 has a sixth side wall 370. Any one of the third side wall 340, the fourth side wall 350, the fifth side wall 360, and the sixth side wall 370 faces the outer peripheral wall of the rotor core 20.

[0300] The third side wall 340 and the fourth side wall 350 form an included angle b1, and the fifth side wall 360 and the sixth side wall 370 form an included angle b2.

[0301] The included angle b1 is called the outer magnetic pole included angle b1, and the included angle b2 is called the inner magnetic pole included angle b2.

[0302] b1 and b2 satisfy 0° ≤ b1 - b2 ≤ 50°

[0303] As Figure 16 shown, in the motor 1 with 48 slots and 8 poles as an example, the curve data graph of the permanent magnet torque and reluctance torque of the motor 1 changing with the value of b1 - b2. Among them, B7 represents the permanent magnet torque, and B8 represents the reluctance torque. The total output torque of the motor 1 = permanent magnet torque + reluctance torque. It can be seen from Figure 16 that when b1 < b2, both the permanent magnet torque and the reluctance torque are on a downward trend, that is, the total output torque of the motor 1 decreases. When b1 and b2 satisfy 0° ≤ b1 - b2 ≤ 50°, their permanent magnet torque and reluctance torque are on an increasing trend at the same time, or in a torque complementary trend where one increases and the other decreases. When the magnitude of b1 - b2 gradually increases to more than 50°, the permanent magnet torque and reluctance torque of the motor 1 are both on a downward trend again.

[0304] As Figure 8 and Figure 9 shown, the rotor core 20 includes 6 core segments 710, and is composed of 6 rotor cores 20 with n = 6. The 6 core segments 710 are arranged in a V shape along the axial direction. There is a circumferential misalignment angle between the first core segment 710 and the second core segment 710. There is a circumferential misalignment angle between the second core segment 710 and the third core segment 710. There is no circumferential misalignment angle between the third core segment 710 and the fourth core segment 710 along the circumferential direction of the rotor core 20, and they are linearly connected along the axial direction of the rotor core 20. There is a circumferential misalignment angle between the fourth core segment 710 and the fifth core segment 710, and there is a circumferential misalignment angle between the fifth core segment 710 and the sixth core segment 710.

[0305] In this connection method, the maximum rotation angle θ between the core segments 710 can be the skewed pole angle θ1 between the first core segment 710 and the second core segment 710, or the skewed pole angle θ2 between the second core segment 710 and the third core segment 710. The maximum skewed pole angle θ is the maximum of θ1 and θ2.

[0306] It can be understood that when the number of n is more and they are not arranged in a V shape, the maximum skew pole angle between the core segments 710 can be the maximum of the skew pole angles of any two adjacent and stagger - arranged core segments 710. When designing the skew pole angle of the rotor of the present application, by adding skew pole angles of different types of core segments 710, the cogging torque, torque ripple, and radial electromagnetic force of the rotor are affected. Therefore, the skew pole angle obtained by using the calculation method of the embodiment of the present application can more accurately calculate the optimal skew pole angle to reduce the influence of the cogging torque, torque ripple, and radial electromagnetic force on the noise. Whether for an integer - slot motor 1 or a fractional - slot motor 1, the influence of the radial electromagnetic force on the noise of the motor 1 can be significantly reduced.

[0307] Next, taking a 48 - slot 8 - pole motor 1 as an example, the function of the rotor of the present application will be further described in detail. The number of stator slots 130 of the motor 1, Z = 48, the number of rotor poles 2p = 8, the number of core segments 710, n = 6, Nc = LCM(Z, 2×p)=48, θ0 = 360° / (n×Nc)=1.25°, 0≤Δθ≤1.25°. The maximum skew pole angle θ of the skew pole angles of each core segment 710 obtained by using the present application can be in the range of 1.25° to 2.5°. As shown in Table 1, compared with the straight - pole scheme in the related art, when θ = 1.25° or θ = 2.5°, its torque ripple, the 48 - order electromagnetic forces of the motor 1 under loaded and no - load conditions all decrease significantly, and the corresponding noise can be significantly reduced.

[0308] Table 1

[0309]

[0310] In the present application, the term "a plurality of" refers to two or more, unless otherwise clearly defined. Terms such as "mounted", "connected", "joined", "fixed", etc. should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; "joined" can be a direct connection or an indirect connection through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances.

[0311] In the description of this specification, the descriptions of terms such as "one embodiment", "some embodiments", "specific embodiments", etc. mean that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or instance. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. The above is only the preferred embodiment of the present application and is not used to limit the present application. For those skilled in the art, the present application can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A motor, characterized in that, include: stator core; a rotor core rotatably disposed within the stator core, wherein an air gap is enclosed between an outer circumferential wall of the rotor core and an inner circumferential wall of the stator core, wherein a maximum value of the air gap is denoted as H1 and a minimum value of the air gap is denoted as H2 from the rotor core to the stator core; The rotor core is provided with an axial hole and a plurality of magnetic pole portions, wherein the plurality of magnetic pole portions are spaced apart and arranged around the axial hole; The magnetic pole portion includes a first magnetic slot group and a second magnetic slot group, wherein the second magnetic slot group is located between the first magnetic slot group and the shaft hole; Either the first magnetic slot group or the second magnetic slot group includes two magnet slots, each of the magnet slots including an inner end close to the shaft hole and an outer end away from the shaft hole, the inner ends of the two magnet slots being close to each other, the outer ends of the two magnet slots being away from each other, the two magnet slots being symmetrically arranged with the magnetic pole center line of the rotor core as the center axis, the magnet slots including a permanent magnet segment and a magnetic isolation segment, the permanent magnet segment and the magnetic isolation segment being in communication; In the magnet slots of the first magnetic slot group, the connection points of the permanent magnet segment and the two magnetic isolation segments facing away from the axial hole are respectively recorded as a first vertex and a second vertex, a first radially extending line passing through the center of the axial hole intersects or is tangent to the first vertex, and a second radially extending line passing through the center of the axial hole intersects or is tangent to the second vertex, and an angle formed by the first radially extending line and the second radially extending line is recorded as θ1; In the magnet slots of the second magnetic slot group, the connection points of the permanent magnet segment and the two magnetic isolation segments facing away from the axial hole are respectively recorded as the third vertex and the fourth vertex, a third radial extension line passing through the center of the axial hole intersects or is tangent to the third vertex, and a fourth radial extension line passing through the center of the axial hole intersects or is tangent to the fourth vertex, and an angle formed by the third radial extension line and the fourth radial extension line is recorded as θ2; Among them, 0.12≤(H1-H2) / (H1+H2)≤0.33, 1.64≤θ2 / θ1≤2.

1.

2. The motor according to claim 1, characterized in that, The stator core comprises: annular yoke; a plurality of teeth, the plurality of teeth being spaced apart along the circumference of the stator core, the teeth comprising a tooth body and a tooth shoe, the tooth body being connected between the tooth shoe and the inner circumferential wall of the annular yoke, any two adjacent teeth and the annular yoke enclosing a stator slot, the tooth shoe being arranged opposite to the rotor core; In any two adjacent tooth portions, along the circumferential direction of the stator core, the side walls of the two tooth bodies close to each other are respectively recorded as a first side wall and a second side wall, and the first side wall and the second side wall are arranged in parallel.

3. The motor according to claim 2, characterized in that, Along the circumference of the stator core, the width of the end of the tooth body away from the annular yoke is recorded as Wt, and the distance from the first side wall to the second side wall is recorded as Ws, wherein 0.95≤Wt / Ws≤1.

45.

4. The motor according to claim 3, characterized in that, The number of the stator slots is denoted as s, and the inner diameter of the stator core is denoted as Ds2, wherein 0.47×π×(Ds2 / s)≤Wt≤1.45×Ws.

5. The electric machine according to any one of claims 2 to 4, characterized in that, The annular yoke portion has a structure with an equal annular width. The annular width of the annular yoke portion is denoted as Ys, the outer diameter of the stator core is denoted as Ds1, and the split ratio of the stator core is denoted as k. Among them, 0.13 ≤ Ys / (1 - k) / Ds1 ≤ 0.25, and 0.65 ≤ k ≤ 0.

79.

6. The electric machine according to any one of claims 2 to 4, characterized in that It further includes: A plurality of winding portions, and any one of the plurality of winding portions is disposed in one of the stator slots. The winding portion includes a plurality of winding segments, and the plurality of winding segments are arranged in the direction from the annular yoke portion to the tooth portion; The length of the winding segment in the circumferential direction of the stator core is denoted as L1, and the length of the winding segment in the direction from the tooth portion to the annular yoke portion is denoted as L2. Among them, 1.2 ≤ L1 / L2 ≤ 2.

5.

7. The electric machine according to any one of claims 1 to 4, characterized in that The portion of the outer peripheral wall of the rotor core opposite to the magnetic pole portion includes an intermediate arc segment, a first side arc segment, and a second side arc segment. The intermediate arc segment is located between the first side arc segment and the second side arc segment, and the intermediate arc segment is opposite to the first magnetic slot group; The radius corresponding to any one of the first side arc segment and the second side arc segment is smaller than the radius corresponding to the intermediate arc segment; The value of the gap between one of the first side arc segment and the second side arc segment and the inner peripheral wall of the stator core is the maximum value of the air gap, and the value of the gap between the intermediate arc segment and the inner peripheral wall of the stator core is the minimum value of the air gap.

8. The electric machine according to any one of claims 1 to 4, characterized in that, In the two magnet slots of the first magnetic slot group, the permanent magnet segment of one magnet slot has a third side wall, and the permanent magnet segment of the other magnet slot has a fourth side wall. Any one of the third side wall and the fourth side wall faces the outer peripheral wall of the rotor core, and the third side wall and the fourth side wall form an angle b1; In the two magnet slots of the second magnetic slot group, the permanent magnet segment of one magnet slot has a fifth side wall, and the permanent magnet segment of the other magnet slot has a sixth side wall. Any one of the fifth side wall and the sixth side wall faces the outer peripheral wall of the rotor core, and the fifth side wall and the sixth side wall form an angle b2; Among them, 0° ≤ b1 - b2 ≤ 50°.

9. The electric machine according to any one of claims 1 to 4, characterized in that, The rotor core is provided with a plurality of weight-reducing holes, and the plurality of weight-reducing holes are arranged at intervals. The weight-reducing holes are located on the magnetic pole center line or the inter-pole center line of the rotor core; The number of the weight-reducing holes is 2 × N1 × p, where N1 is a positive integer and p is the number of pole pairs of the motor.

10. The motor according to claim 9, characterized in that, The minimum distance from the plurality of weight-reducing holes to the outer peripheral wall of the rotor core is denoted as L3, the radius of the shaft hole is denoted as R1, and the radius of the rotor core is denoted as R2. Among them, 0.45 ≤ L3 / (R2 - R1) ≤ 0.

77.

11. The electric machine according to any one of claims 1 to 4, characterized in that Along the inner end to the outer end, the width of the permanent magnet segment of the first magnetic slot group is denoted as W1, and the width of the permanent magnet segment of the second magnetic slot group is denoted as W2. Among them, 0.17 ≤ (W2 - W1) / (W2 + W1) ≤ 0.

49.

12. The electric machine according to any one of claims 2 to 4, characterized in that, Along the axial direction of the rotor core, the rotor core includes a plurality of core groups, and each core group includes a plurality of stacked core segments; Any two adjacent core segments in the core group are arranged with a circumferential misalignment on the rotor core. The misalignment angle is denoted as θ. The total number of core segments of the multiple core groups is denoted as n, where n ≥ 2. The number of stator slots is denoted as Z, and the number of pole pairs of the motor is denoted as p; θ = θ0 + Δθ, θ0 = 360° / (n×Nc), Nc = LCM(Z, 2×p), 0° ≤ Δθ ≤ θ0.

13. A power system, characterized in that, Comprising: The motor according to any one of claims 1 to 12.

14. A vehicle, characterized in that, Comprising: The motor according to any one of claims 1 to 12; Or The power system according to claim 13.

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