Rotor laminations, rotor cores, rotors, motors, and vehicles

Abstract

This invention provides a rotor lamination, a rotor core, a rotor, a motor, and a vehicle. The rotor lamination has multiple mounting slots for mounting permanent magnets. Each mounting slot, with the portion fitted with the permanent magnet, defines a pole arc region between itself and the outer periphery of the rotor lamination. Magnetic isolation bridges are provided on both sides of each pole arc region along the circumferential direction of the rotor lamination. Each pole arc region has multiple through holes distributed at two ends of the pole arc region near the magnetic isolation bridges. The rotor lamination provided by this invention, by providing through holes at the ends of the pole arc region near the magnetic isolation bridges on both sides, optimizes the rotor magnetic field distribution, effectively weakens the cross-axis armature reaction, significantly improves motor torque pulsation, and also enhances the electromagnetic torque of the motor to a certain extent, thus improving the motor's operating performance.

Description

[0001] This application is a divisional application of Chinese patent application filed on August 7, 2019, with application number "201910724193.8" and invention title "Rotor Lamination, Rotor Core, Rotor, Motor and Vehicle". Technical Field

[0002] This invention relates to the field of electric motor technology, and more specifically, to a rotor lamination, a rotor core comprising the rotor lamination, a rotor comprising the rotor core, an electric motor comprising the rotor, and a vehicle comprising the electric motor. Background Technology

[0003] Currently, for built-in permanent magnet synchronous motors, under high load conditions, the magnetic field distortion caused by armature reaction, especially quadrature axis armature reaction, is particularly prominent. This leads to large torque fluctuations in the motor when the core is in a high saturation state, resulting in significant noise. This contradicts the lower NVH (Noise, Vibration, Harshness) requirements in some applications, such as power steering systems. Summary of the Invention

[0004] In order to solve at least one of the above-mentioned technical problems, the first objective of the present invention is to provide a rotor lamination.

[0005] A second objective of the present invention is to provide a rotor core comprising the aforementioned rotor laminations.

[0006] A third objective of the present invention is to provide a rotor comprising the aforementioned rotor core.

[0007] A fourth object of the present invention is to provide an electric motor including the rotor described above.

[0008] A fifth object of the present invention is to provide a vehicle with the above-mentioned motor.

[0009] To achieve the above objectives, the first aspect of the present invention provides a rotor lamination, wherein the rotor lamination is provided with a plurality of mounting slots for mounting permanent magnets, and a pole arc region is defined between the portion of any mounting slot that adapts to the permanent magnet and the outer periphery of the rotor lamination, and magnetic isolation bridges are provided on both sides of any pole arc region along the circumferential direction of the rotor lamination; wherein, any pole arc region is provided with a plurality of through holes, and the plurality of through holes are distributed at two ends of the pole arc region adjacent to the magnetic isolation bridges.

[0010] The rotor lamination provided by the first aspect of the present invention optimizes the rotor magnetic field distribution by setting through holes at the ends of the pole arc region near the magnetic isolation bridges on both sides. This effectively weakens the cross-axis armature reaction, significantly improves motor torque pulsation, reduces motor operating noise and NVH, and enhances user comfort. Simultaneously, it also improves the motor's electromagnetic torque to a certain extent, which is beneficial for improving the motor's performance. In other words, because the magnetic saturation at the two ends of the pole arc region near the magnetic isolation bridges is higher than that in the middle, it is more prone to magnetic field distortion. Therefore, this solution sets through holes at the two ends of the pole arc region near the magnetic isolation bridges to optimize the magnetic field distribution, thereby improving magnetic field distortion and solving the problem of large torque fluctuations that often occur in motors under high core saturation conditions.

[0011] In addition, the rotor laminations in the above-mentioned technical solutions provided by the present invention may also have the following additional technical features:

[0012] In the above technical solution, all the through holes in any of the pole arc regions are distributed circumferentially along the rotor laminations and are symmetrically distributed about the center line of the corresponding magnetic pole.

[0013] All through holes within any pole arc region are distributed circumferentially along the rotor laminations and are symmetrical about the center line of the corresponding magnetic pole, making the rotor laminations more regular in structure and easier to process and form; at the same time, it makes the magnetic field distribution more uniform, and thus the waveform of the electromagnetic torque is more regular, which is conducive to further reducing torque pulsation.

[0014] In the above technical solution, the number of through holes located at any of the ends is multiple.

[0015] The number of through holes at any end of any polar arc region is designed to be multiple. Multiple through holes can further optimize the magnetic field distribution, which is beneficial to further improve the torque ripple problem.

[0016] In the above technical solution, the number of through holes located at any of the ends is 1-4.

[0017] The number of through holes at any end is limited to 1 to 4 (i.e., 1, 2, 3 or 4) to prevent excessive openings from causing excessive magnetic circuit equivalent reluctance and reducing the electromagnetic torque of the motor.

[0018] In the above technical solution, the angle θ between the geometric center of the two innermost through holes in the same pole arc region and the center of the rotor lamination satisfies: 0.55≤θ / (360° / (2×P))≤0.7, where P is the number of pole pairs of the motor.

[0019] The two innermost through holes in the same polar arc region refer to: the through holes closest to the corresponding magnetic pole center line at the two ends of the same polar arc region, or the through holes farthest from the adjacent magnetic isolation bridge at the two ends of the same polar arc region. Of course, if there is only one through hole at any end, the two innermost through holes in the same polar arc region are these two through holes.

[0020] The angle θ between the lines connecting the geometric centers of the two innermost through holes in the same pole arc region and the center of the rotor lamination refers to the angle between the first and second lines: the line connecting the geometric center of one through hole to the center of the rotor lamination is denoted as the first line, and the line connecting the geometric center of the other through hole to the center of the rotor lamination is denoted as the second line. The ratio of 360° to 2×P refers to the angular region occupied by one magnetic pole. The ratio of θ to this angular region can characterize the positions of the through holes at the two ends within the same pole arc region. Specifically, the larger the ratio, the further out the through holes are at the two ends, the smaller the distance between them and the adjacent magnetic bridge, and the better the effect on improving motor torque ripple; the smaller the ratio, the further inward the through holes are at the two ends, the larger the distance between them and the adjacent magnetic bridge, and the worse the effect on improving motor torque ripple. This scheme limits the ratio to the range of 0.55 to 0.7 (i.e., 0.55, 0.6, 0.65, 0.7, etc.), so that the through hole is as close as possible to the magnetic bridge, thereby ensuring that the through hole appears in the region of relatively saturated magnetic flux, which can effectively adjust the magnetic field distribution and effectively improve torque ripple; at the same time, it also ensures that the area where the through hole is located is not too large, so that the number of through holes is not too many or the opening is too large, which can prevent the equivalent magnetic reluctance of the magnetic circuit from being too large due to too many openings, thus reducing the electromagnetic torque of the motor.

[0021] In the above technical solution, along the direction close to the center line of the corresponding magnetic pole, the dimension of the nth through hole at any end along the length direction of the mounting groove is denoted as Wn, and the width of the distance between the nth through hole and the (n-1)th through hole is denoted as D. n-1 The dimension of the permanent magnet along the length of the mounting groove is denoted as Wm; where 0.15 ≤ 2 × (W1 + W2 + ... + Wn + D1 + D2 + ... + D n-1 ) / Wm≤0.35.

[0022] The sum of the widths of all through holes at any end and the sum of the distances between two adjacent through holes constitute the sum of the widths of the opening areas at one end of any pole arc region. Twice this sum constitutes the total width of the opening areas at both ends of a pole arc region. Limiting the ratio of this total width to the dimension Wm of the permanent magnet along the length of the mounting groove (i.e., the width of the permanent magnet corresponding to the mounting groove, or the cross-sectional length of the permanent magnet on the section where the mounting groove is located) within the aforementioned range (e.g., 0.15, 0.2, 0.25, 0.3, 0.35) can prevent the opening areas from being too wide, thereby avoiding excessively large or numerous openings that could lead to excessively high equivalent magnetic reluctance in the magnetic circuit and reduce motor torque. Therefore, it is beneficial to improve motor torque ripple while also considering the magnitude of the motor's electromagnetic torque.

[0023] It is understandable that in the above formula (W1+W2+…+Wn+D1+D2+…+D…), the expression is incorrect. n-1 This represents the sum of the total width of all through holes at one end and the total width of the spacing between these through holes; that is, the total width of the opening area at one end. It can also be written as... Since the number of through holes at one end can be one, two, three, or more, the above formula means: when n = 1, 0.15 ≤ 2 × W1 / Wm ≤ 0.35; when n = 2, 0.15 ≤ 2 × (W1 + W2 + D1) / Wm ≤ 0.35; when n = 3, 0.15 ≤ 2 × (W1 + W2 + W3 + D1 + D2) / Wm ≤ 0.35; when n = 4, 0.15 ≤ 2 × (W1 + W2 + W3 + W4 + D1 + D2 + D3) / Wm ≤ 0.35; when n ≥ 4, 0.15 ≤ 2 × (W1 + W2 + … + Wn + D1 + D2 + … + D n-1 ) / Wm≤0.35.

[0024] In the above technical solution, the two ends of the mounting groove are constructed as magnetic isolation holes, and the magnetic isolation holes and the outer periphery of the rotor lamination form the magnetic isolation bridge. The minimum distance d between the through hole and the adjacent magnetic isolation bridge and the minimum spacing D between two adjacent through holes located at any of the ends satisfy: d≤k×D, where k∈[0.5,2].

[0025] The two ends of the mounting slot are constructed as magnetic isolation holes. That is, the size of the mounting slot is larger than the size of the permanent magnet. After the permanent magnet is inserted into the mounting slot, there is a certain gap between it and the two ends of the slot, which can suppress magnetic leakage between poles. The area between the part of the mounting slot where the permanent magnet is inserted and the outer periphery of the rotor lamination is the pole arc region. The area between the magnetic isolation holes at both ends of the mounting slot and the outer periphery of the rotor lamination is the magnetic isolation bridge. Therefore, magnetic isolation bridges are provided on both sides of the pole arc region. The principle of the magnetic isolation bridge is to limit magnetic leakage by achieving magnetic flux saturation at the bridge location. Limiting the relationship between d and D within the above range is beneficial for each through hole to be as close as possible to the adjacent magnetic isolation bridge, thereby further improving the effect of reducing electromagnetic torque fluctuations. k can be in the range of 0.5 to 2, such as 0.5, 0.8, 1, 1.2, 1.5, 1.8, and 2.

[0026] In the above technical solution, the minimum distance D between two adjacent through holes located at any of the ends is greater than or equal to the thickness of the rotor lamination.

[0027] By ensuring that the minimum spacing between two adjacent through holes at any end is greater than or equal to the thickness of the rotor lamination, the area between the two through holes is prevented from being too thin and prone to breakage, thereby improving the strength of the rotor lamination and enhancing the reliability of the rotor.

[0028] In the above technical solution, along the direction close to the center line of the corresponding magnetic pole, the dimension H of the through hole located at any of the ends gradually increases along the width direction of the corresponding mounting groove; and / or, along the direction close to the center line of the corresponding magnetic pole, the dimension W of the through hole located at any of the ends gradually increases along the length direction of the corresponding mounting groove.

[0029] Since the mounting slot is generally elongated and extends roughly along the circumferential direction of the rotor lamination, its length is approximately equal to the circumferential direction of the rotor lamination, and its width is approximately equal to the radial direction of the rotor lamination. Correspondingly, the dimension of the through-hole within the pole arc region along the width of the corresponding mounting slot can be understood as the height of the through-hole, and the dimension along the length of the corresponding mounting slot can be understood as the width of the through-hole. Thus, along the direction close to the centerline of the corresponding magnetic pole, the dimension of the through-hole at any end gradually increases along the width of the mounting slot. That is, the height of the through-hole closer to the centerline of the magnetic pole is relatively high. This matches the shape of the pole arc region, which is beneficial for increasing the size of the through-hole to further improve the effect of reducing motor torque ripple, while also taking into account the strength of the rotor and preventing the rotor lamination from becoming excessively thin locally. Similarly, along the direction close to the center line of the corresponding magnetic pole, the size of the through hole at any end gradually increases along the length of the mounting groove. That is, the width of the through hole close to the center line of the magnetic pole is relatively wide, which is compatible with the shape of the pole arc region. This is beneficial to increase the size of the through hole to further improve the effect of improving the motor torque pulsation, while also taking into account the strength of the rotor and preventing the rotor laminations from becoming too thin locally.

[0030] In any of the above technical solutions, the dimension H of the through hole along the width direction of the corresponding mounting groove and the dimension W of the through hole along the length direction of the corresponding mounting groove satisfy: 3.5≥(H / W)≥1.

[0031] Limiting the ratio of the height to the width of the through hole to the range of 1 to 3.5, such as 1, 1.5, 2, 2.5, 3, 3.5, etc., makes the through hole form an elongated structure that extends roughly along the radial direction of the rotor lamination, such as a waist-shaped hole, a rectangular hole, an elliptical hole, etc., which matches the shape of the pole arc region. This helps to increase the size of the through hole, thereby further improving the effect of reducing motor torque pulsation.

[0032] In any of the above technical solutions, the dimension W of the through hole along the length direction of the corresponding mounting groove is greater than or equal to 0.3 mm; and / or, the dimension H of the through hole along the width direction of the corresponding mounting groove is greater than or equal to 0.3 mm.

[0033] The dimension of the through hole along the length of the corresponding mounting groove (i.e., the width of the through hole) is greater than or equal to 0.3mm. This can prevent the through hole from being too narrow, which would result in a weak effect on improving the magnetic field distribution and is beneficial to improving the effect of reducing motor torque pulsation.

[0034] The dimension of the through hole along the width direction of the corresponding mounting groove (i.e., the height of the through hole) is greater than or equal to 0.3mm. This can prevent the through hole from being too short, which would result in a weak effect on improving the magnetic field distribution and is beneficial to improving the effect of reducing motor torque pulsation.

[0035] In any of the above technical solutions, the minimum distance Lmin between the through hole and the outer periphery of the rotor lamination is greater than or equal to the thickness of the rotor lamination.

[0036] The minimum distance Lmin between the through hole and the outer periphery of the rotor lamination is greater than or equal to the thickness of the rotor lamination. This can prevent the outer periphery of the rotor lamination from being too thin and easily broken, thereby improving the strength of the rotor lamination and the reliability of the rotor.

[0037] In any of the above technical solutions, the through hole has a notch that penetrates the outer periphery of the rotor lamination; or, the through hole has a notch that connects to the corresponding mounting groove; or, the through hole is a closed annulus.

[0038] The through hole has a notch that penetrates the outer periphery of the rotor lamination. That is, the through hole is located relatively outward and is not a closed ring. In other words, the through hole can be formed by partially indenting the outer periphery of the rotor lamination, which makes processing easier and reduces processing difficulty. It also helps to increase the distance between the through hole and the mounting slot, thereby ensuring the strength of the rotor lamination.

[0039] Alternatively, the through hole has a notch connecting to the corresponding mounting groove, meaning the through hole is located relatively inward and is not a closed ring. In other words, the through hole can be formed by the outer edge of the mounting groove protruding outward. Therefore, the through hole and the mounting groove can be integrally formed, which helps to reduce the processing difficulty and also increases the distance between the through hole and the outer periphery of the rotor lamination, thereby ensuring the strength of the rotor lamination.

[0040] Alternatively, the through hole can be a complete ring, meaning that the through hole is located entirely within the pole arc region and has gaps between it and the outer periphery of the rotor lamination and the mounting groove. The structure is relatively independent and can be easily processed into various required shapes as needed.

[0041] In any of the above technical solutions, the shape of the through hole is rectangular, circular, elliptical, or a strip formed by a combination of rectangle and semicircle; and / or, multiple through holes have the same shape.

[0042] The through-hole can be rectangular, circular, elliptical, or a long strip formed by combining a rectangle and a semicircle. Its structure is relatively regular and easy to process and shape. Of course, the shape of the through-hole is not limited to the above shapes and can be any other shape.

[0043] Multiple through holes can have the same shape, such as all rectangular, all circular, all elliptical, or a combination of rectangles and semicircles forming an elongated shape. This allows for a more regular rotor lamination structure, facilitating processing and forming. It's worth noting that while multiple through holes may have the same shape, their dimensions can differ. For example, through holes closer to the magnetic bridge can be smaller, while those closer to the magnetic pole centerline can be larger.

[0044] The second aspect of the present invention provides a rotor core comprising: a plurality of rotor laminations as described in any one of the first aspects of the present invention, wherein the plurality of rotor laminations are stacked to form the rotor core, and mounting slots of the plurality of rotor laminations form mounting holes.

[0045] The rotor core provided by the second aspect of the present invention, having included the rotor laminations described in any one of the first aspects of the present invention, has all the beneficial effects of any of the above-mentioned technical solutions, which will not be repeated here.

[0046] The third aspect of the present invention provides a rotor, comprising: a rotor core as described in the second aspect; and a plurality of permanent magnets inserted into mounting holes in the rotor core.

[0047] The rotor provided by the third aspect of the present invention, having the rotor core described in the second aspect, possesses all the beneficial effects of any of the above-mentioned technical solutions, which will not be repeated here.

[0048] In the above technical solution, the cross-section of the permanent magnet perpendicular to the axis of the rotor is I-shaped, V-shaped, or U-shaped.

[0049] The cross-section of the permanent magnet perpendicular to the rotor axis can be I-shaped, V-shaped, or U-shaped, or other shapes. This expands the types of permanent magnets that can be adapted to the rotor core, which helps to increase the applicability of the product.

[0050] The fourth aspect of the present invention provides an electric motor, comprising: a rotor as described in the third aspect; and a stator, which is fitted together with the rotor.

[0051] The motor provided by the fourth aspect of the present invention includes the rotor described in any one of the third aspects of the technical solution, and therefore has all the beneficial effects of any of the above technical solutions, which will not be repeated here.

[0052] The fifth aspect of the present invention provides a vehicle, comprising: a vehicle body; and a motor as described in the fourth aspect, installed in the vehicle body.

[0053] The vehicle provided by the fifth aspect of the present invention, having included the motor described in the fourth aspect, possesses all the beneficial effects of any of the aforementioned technical solutions, which will not be repeated here.

[0054] Additional aspects and advantages of the invention will become apparent in the following description or may be learned by practice of the invention. Attached Figure Description

[0055] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0056] Figure 1 This is a schematic diagram of the rotor lamination structure according to one embodiment of the present invention;

[0057] Figure 2 yes Figure 1 Enlarged structural diagram of section A in the middle;

[0058] Figure 3 yes Figure 1 Another partial structural diagram of the rotor lamination shown;

[0059] Figure 4 This is a schematic diagram of the rotor lamination structure according to one embodiment of the present invention;

[0060] Figure 5 This is a schematic diagram of the rotor lamination structure according to one embodiment of the present invention;

[0061] Figure 6 yes Figure 5 A schematic diagram of a partial structure of the rotor lamination shown;

[0062] Figure 7 This is a side view of the rotor core structure according to an embodiment of the present invention;

[0063] Figure 8 This is a comparison diagram of torque waveforms between a specific example of the present invention and a prior art comparative example.

[0064] in, Figures 1 to 7 The correspondence between the reference numerals and component names in the attached drawings is as follows:

[0065] 1. Rotor laminations, 11. Pole arc area, 12. Mounting slot, 121. Magnetic isolation hole, 13. Through hole, 14. Magnetic isolation bridge, 2. Rotor core. Detailed Implementation

[0066] To better understand the above-mentioned objectives, features, and advantages of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0067] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and therefore the scope of protection of the invention is not limited to the specific embodiments disclosed below.

[0068] The following reference Figures 1 to 8 The invention describes rotor laminations, rotor cores, rotors, motors, and vehicles according to some embodiments of the invention.

[0069] Example 1

[0070] The rotor lamination 1 provided in the first aspect of the present invention has a plurality of mounting slots 12 for mounting permanent magnets. A pole arc region 11 is defined between the portion of any mounting slot 12 that accommodates the permanent magnet and the outer periphery of the rotor lamination 1. Magnetic isolation bridges 14 are provided on both sides of any pole arc region 11 along the circumferential direction of the rotor lamination 1. Figure 1 As shown; wherein, any polar arc region 11 is provided with multiple through holes 13, and the multiple through holes 13 are distributed at the two ends of the polar arc region 11 near the magnetic isolation bridge 14, as shown. Figure 1 As shown.

[0071] The rotor lamination 1 provided in this embodiment optimizes the rotor magnetic field distribution by setting through holes 13 at the ends of the pole arc region 11 near the magnetic isolation bridges 14 on both sides, effectively weakens the cross-axis armature reaction, significantly improves the motor torque pulsation, and also improves the electromagnetic torque of the motor to a certain extent, which is beneficial to improving the working performance of the motor.

[0072] In other words, since the magnetic saturation at the two ends of the pole arc region 11 near the magnetic isolation bridge 14 is higher than that in the middle part, it is more likely to cause magnetic field distortion. Therefore, this solution sets through holes 13 at the two ends of the pole arc region 11 near the magnetic isolation bridge 14 to optimize the magnetic field distribution, thereby improving the magnetic field distortion and solving the problem of large torque fluctuations in the motor under high core saturation.

[0073] Furthermore, all the through holes 13 in any pole arc region 11 are distributed at circumferential intervals along the rotor lamination 1, and are symmetrically distributed about the center line of the corresponding magnetic pole, such as... Figure 1 As shown.

[0074] All through holes 13 within any pole arc region 11 are distributed circumferentially along the rotor lamination 1 and are symmetrical about the center line of the corresponding magnetic pole (that is, the direct axis of the magnetic pole), making the structure of the rotor lamination 1 more regular and easier to process and form; at the same time, it makes the magnetic field distribution more uniform, and thus the waveform of the electromagnetic torque is more regular, which is conducive to further reducing torque pulsation.

[0075] Optionally, the number of through holes 13 located at either end can be multiple, such as... Figure 1 and Figure 2 As shown.

[0076] The number of through holes 13 at any end of any polar arc region 11 can be designed to be multiple (such as two, three, etc.). Multiple through holes 13 can further optimize the magnetic field distribution, which is beneficial to further improve the torque fluctuation problem.

[0077] Of course, the number of through holes 13 located at either end can also be one.

[0078] Optionally, the number of through holes 13 located at either end is 1 to 4.

[0079] The number of through holes 13 located at either end is limited to 1 to 4 (i.e., 1, 2, 3 or 4) to prevent excessive openings from causing excessive magnetic circuit equivalent magnetic reluctance and reducing the electromagnetic torque of the motor.

[0080] Furthermore, the angle θ between the geometric center of the two innermost through holes 13 in the same pole arc region 11 and the center of the rotor lamination 1 satisfies: 0.55≤θ / (360° / (2×P))≤0.7, where P is the number of pole pairs of the motor.

[0081] Furthermore, the two innermost through holes 13 in the same polar arc region 11 refer to: the through hole 13 closest to the corresponding magnetic pole center line at the two ends of the same polar arc region 11, or the through hole 13 farthest from the adjacent magnetic isolation bridge 14 at the two ends of the same polar arc region 11. Of course, if there is only one through hole 13 at any end, then the two innermost through holes 13 in the same polar arc region 11 are those two through holes 13.

[0082] The angle θ between the geometric centers of the two innermost through holes 13 in the same polar arc region 11 and the center of the rotor lamination 1 refers to the following: the line connecting the geometric center of one through hole 13 and the center of the rotor lamination 1 is called the first line, and the line connecting the geometric center of the other through hole 13 and the center of the rotor lamination 1 is called the second line. The angle between the first line and the second line is θ.

[0083] The ratio of 360° to 2×P refers to the angular region occupied by a magnetic pole. The ratio of θ to this angular region can characterize the positions of the through holes 13 at the two ends within the same pole arc region 11. Specifically, the larger the ratio, the further out the through holes 13 at the two ends are, the smaller the distance between them and the adjacent magnetic isolation bridge 14, and the better the effect on improving motor torque ripple. The smaller the ratio, the further in the through holes 13 at the two ends are, the larger the distance between them and the adjacent magnetic isolation bridge 14, and the worse the effect on improving motor torque ripple.

[0084] This scheme limits the ratio to the range of 0.55 to 0.7 (i.e., 0.55, 0.6, 0.65, 0.7, etc.), so that the through hole 13 is as close as possible to the magnetic isolation bridge 14, thereby ensuring that the through hole 13 appears in the region of relatively saturated magnetic flux, which can effectively adjust the magnetic field distribution and effectively improve torque pulsation; at the same time, it also ensures that the area where the through hole 13 is located is not too large, so that the number of through holes 13 is not too many or the opening is too large, which can prevent the equivalent magnetic reluctance of the magnetic circuit from being too large due to too many openings, thus reducing the electromagnetic torque of the motor.

[0085] Furthermore, such as Figure 3 As shown, along the direction close to the center line of the corresponding magnetic pole, the dimension of the nth through hole 13 at any end along the length of the mounting groove 12 is denoted as Wn, and the width of the distance between the nth through hole 13 and the (n-1)th through hole 13 is denoted as D. n-1 The dimension of the permanent magnet along the length of the mounting groove 12 is denoted as Wm; where 0.15≤2×(W1+W2+…+Wn+D1+D2+…+D n-1 ) / Wm≤0.35.

[0086] The sum of the widths of all through holes 13 at any end and the sum of the distances between two adjacent through holes 13 constitute the sum of the widths of the opening areas at one end of any pole arc region 11. Twice this sum constitutes the total width of the opening areas at both ends of a pole arc region 11. Limiting the ratio of this total width to the dimension Wm of the permanent magnet along the length of the mounting groove 12 (i.e., the width of the permanent magnet corresponding to the mounting groove 12, or the cross-sectional length of the permanent magnet on the section where the mounting groove 12 is located) within the aforementioned range (e.g., 0.15, 0.2, 0.25, 0.3, 0.35) can prevent the opening areas from being too wide, thereby avoiding excessively large or numerous openings that could lead to excessively high equivalent magnetic reluctance in the magnetic circuit and reduce motor torque. Therefore, it is beneficial to improve motor torque pulsation while also considering the magnitude of the motor's electromagnetic torque.

[0087] It is understandable that in the above formula (W1+W2+…+Wn+D1+D2+…+D…), the expression is incorrect. n-1The width of a hole represents the sum of the total width of all the through holes 13 at one end and the total width of the spacing between these through holes 13, which is the total width of the opening area at one end. It can also be written as... Since the number of through holes 13 at one end can be 1, 2, 3, or more, the above formula means: when n = 1, 0.15 ≤ 2 × W1 / Wm ≤ 0.35; when n = 2, 0.15 ≤ 2 × (W1 + W2 + D1) / Wm ≤ 0.35; when n = 3, 0.15 ≤ 2 × (W1 + W2 + W3 + D1 + D2) / Wm ≤ 0.35; when n = 4, 0.15 ≤ 2 × (W1 + W2 + W3 + W4 + D1 + D2 + D3) / Wm ≤ 0.35; when n ≥ 4, 0.15 ≤ 2 × (W1 + W2 + … + Wn + D1 + D2 + … + D n-1 ) / Wm≤0.35.

[0088] Furthermore, such as Figure 1 , Figure 4 and Figure 5 As shown, the two ends of the mounting groove 12 are configured as magnetic isolation holes 121, and magnetic isolation bridges 14 are formed between the magnetic isolation holes 121 and the outer periphery of the rotor lamination 1. The minimum distance d between the through hole 13 and the adjacent magnetic isolation bridge 14 is (e.g., ... Figure 3 and Figure 6 The minimum distance D between the two adjacent through holes 13 located at either end (as shown) satisfies: d≤k×D, where k∈[0.5,2].

[0089] The two ends of the mounting groove 12 are configured as magnetic isolation holes 121. That is, the size of the mounting groove 12 is larger than the size of the permanent magnet. After the permanent magnet is inserted into the mounting groove 12, there is a certain gap between it and the two ends of the mounting groove 12, which can suppress magnetic leakage between poles.

[0090] Among them, the area between the part of the mounting groove 12 in which the permanent magnet is inserted and the outer periphery of the rotor lamination 1 is the pole arc region 11, and the area between the magnetic isolation holes 121 at both ends of the mounting groove 12 and the outer periphery of the rotor lamination 1 is the magnetic isolation bridge 14. Therefore, magnetic isolation bridges 14 are provided on both sides of the pole arc region 11. The principle of the magnetic isolation bridge 14 is to limit magnetic leakage by making the magnetic flux at the magnetic bridge part reach saturation.

[0091] Limiting the relationship between d and D to the above range is beneficial for each through hole 13 to be as close as possible to the adjacent magnetic isolation bridge 14, thereby further improving the effect of reducing electromagnetic torque fluctuation.

[0092] Where k is in the range of 0.5 to 2, such as 0.5, 0.8, 1, 1.2, 1.5, 1.8, and 2.

[0093] Furthermore, the minimum spacing D between two adjacent through holes 13 located at either end is greater than or equal to the thickness of the rotor lamination 1.

[0094] By ensuring that the minimum spacing between two adjacent through holes 13 located at either end is greater than or equal to the thickness of the rotor lamination 1, it is possible to prevent the portion between the two through holes 13 from being too thin and prone to breakage, thereby improving the strength of the rotor lamination 1 and enhancing the reliability of the rotor.

[0095] Furthermore, such as Figure 1 and Figure 2 As shown, along the direction close to the center line of the corresponding magnetic pole, the dimension H of the through hole 13 at any end gradually increases along the width direction of the corresponding mounting groove 12.

[0096] like Figure 1 and Figure 2 As shown, along the direction close to the center line of the corresponding magnetic pole, the size W of the through hole 13 at any end gradually increases along the length direction of the corresponding mounting groove 12.

[0097] Since the mounting groove 12 is generally elongated and extends roughly along the circumferential direction of the rotor lamination 1, the length direction of the mounting groove 12 is approximately close to the circumferential direction of the rotor lamination 1, and the width direction of the mounting groove 12 is approximately close to the radial direction of the rotor lamination 1. Correspondingly, the dimension of the through hole 13 in the pole arc region 11 along the width direction of the corresponding mounting groove 12 can be understood as the height of the through hole 13, and the dimension of the through hole 13 along the length direction of the corresponding mounting groove 12 can be understood as the width of the through hole 13.

[0098] Thus, along the direction close to the center line of the corresponding magnetic pole, the size of the through hole 13 at any end gradually increases along the width direction of the mounting groove 12. In other words, the height of the through hole 13 close to the center line of the magnetic pole is relatively high, which is compatible with the shape of the pole arc region 11. This is beneficial to increase the size of the through hole 13 to further improve the effect of improving the motor torque pulsation, while also taking into account the strength of the rotor and preventing the rotor lamination 1 from being too thin locally.

[0099] Similarly, along the direction close to the center line of the corresponding magnetic pole, the size of the through hole 13 at any end gradually increases along the length direction of the mounting groove 12. That is, the width of the through hole 13 near the center line of the magnetic pole is relatively wide, which matches the shape of the pole arc region 11 and helps to increase the size of the through hole 13 to further improve the effect of reducing motor torque pulsation, while also taking into account the strength of the rotor and preventing the rotor lamination 1 from being too thin locally. Furthermore, the size H of the through hole 13 along the width direction of the corresponding mounting groove 12 and the size W of the through hole 13 along the length direction of the corresponding mounting groove 12 satisfy: 3.5 ≥ (H / W) ≥ 1.

[0100] The ratio of the height to the width of the through hole 13 is limited to the range of 1 to 3.5, such as 1, 1.5, 2, 2.5, 3, 3.5, etc., so that the through hole 13 forms an elongated structure that extends roughly along the radial direction of the rotor lamination 1, such as a waist-shaped hole, a rectangular hole, an elliptical hole, etc., which is adapted to the shape of the pole arc region 11. This is beneficial to increase the size of the through hole 13, so as to further improve the effect of improving the motor torque pulsation.

[0101] The dimension W of the through hole 13 along the length direction of the corresponding mounting groove 12 is greater than or equal to 0.3 mm.

[0102] The dimension of the through hole 13 along the length direction of the corresponding mounting groove 12 (i.e., the width W of the through hole 13) is greater than or equal to 0.3mm. This can prevent the through hole 13 from being too narrow, which would result in a weak effect on improving the magnetic field distribution and is beneficial to improving the effect of improving motor torque pulsation.

[0103] Furthermore, the dimension H of the through hole 13 along the width direction of the corresponding mounting groove 12 is greater than or equal to 0.3 mm.

[0104] The dimension of the through hole 13 along the width direction of the corresponding mounting groove 12 (i.e., the height H of the through hole 13) is greater than or equal to 0.3mm. This can prevent the through hole 13 from being too narrow in the longitudinal direction, which would result in a weak effect on improving the magnetic field distribution and is beneficial to improving the effect of improving motor torque pulsation.

[0105] Furthermore, the minimum distance Lmin between the through hole 13 and the outer periphery of the rotor lamination 1 is greater than or equal to the thickness of the rotor lamination 1.

[0106] The minimum distance Lmin between the through hole 13 and the outer periphery of the rotor lamination 1 is greater than or equal to the thickness of the rotor lamination 1. This can prevent the outer periphery of the rotor lamination 1 from being too thin and easily broken, thereby improving the strength of the rotor lamination 1 and improving the reliability of the rotor.

[0107] Optionally, the through hole 13 has a notch that connects to the corresponding mounting groove 12.

[0108] The through hole 13 has a notch that connects to the corresponding mounting groove 12. That is, the position of the through hole 13 is relatively inward, and the through hole 13 is not a closed ring. Therefore, the outer edge of the mounting groove 12 protrudes outward in a local way to form the through hole 13. In this way, the through hole 13 and the mounting groove 12 can be integrally formed, which also helps to reduce the processing difficulty. At the same time, it also helps to increase the distance between the through hole 13 and the outer periphery of the rotor lamination 1, thereby ensuring the strength of the rotor lamination 1.

[0109] Example 2

[0110] The difference from Embodiment 1 is that the through hole 13 has a notch that penetrates the outer periphery of the rotor lamination 1, such as... Figure 4 As shown.

[0111] The through hole 13 has a notch that penetrates the outer periphery of the rotor lamination 1. That is, the position of the through hole 13 is relatively outward, and the through hole 13 is not a closed ring. Therefore, the through hole 13 can be formed by partially indenting the outer periphery of the rotor lamination 1. This makes the processing more convenient and helps to reduce the processing difficulty. At the same time, it also helps to increase the distance between the through hole 13 and the mounting groove 12, thereby ensuring the strength of the rotor lamination 1.

[0112] Example 3

[0113] The difference from Embodiment 1 is that the through hole 13 is a closed annular shape, such as... Figure 5 As shown.

[0114] The through hole 13 is a complete ring, that is, the through hole 13 is completely located inside the pole arc region 11, and there are gaps between it and the outer periphery of the rotor lamination 1 and the mounting groove 12. The structure is relatively independent and it is easy to process it into various required shapes as needed.

[0115] In any of the above embodiments, optionally, the shape of the through hole 13 is rectangular, circular, elliptical, or an elongated shape formed by a combination of a rectangle and a semicircle (e.g., Figure 2 (As shown).

[0116] The shape of the through hole 13 can be rectangular, circular, or elliptical (e.g., Figure 5 and Figure 6 As shown), it can also be a long strip formed by combining a rectangle and a semicircle (as shown). Figures 1 to 3 As shown in the figure, the structure is relatively regular and easy to process and shape.

[0117] Of course, the shape of the through hole 13 is not limited to the shape described above, and can also be as follows: Figure 4 The shape shown is a semicircle or similar to a semicircle or any other arbitrary shape.

[0118] Optionally, the multiple through holes 13 have the same shape, such as Figure 1 and Figure 2 As shown.

[0119] Multiple through holes 13 have the same shape, such as all being rectangular, all being circular, all being elliptical, or all being a combination of rectangles and semicircles to form a long strip. This makes the structure of the rotor lamination 1 more regular and easier to process and form.

[0120] It is worth noting that while the multiple through holes 13 have the same shape, their dimensions and sizes can differ. For example, the through holes 13 closer to the magnetic bridge 14 may be smaller, while those closer to the magnetic pole centerline may be larger. Figure 1 and Figure 2 As shown.

[0121] Optionally, the outer periphery of the rotor lamination 1 can be a regular circle, or it can be like... Figure 1 The shape shown is a ring-shaped wave, or a regular circle with multiple evenly spaced recesses, or other shapes.

[0122] like Figure 7 As shown, the rotor core 2 provided in the second aspect of the present invention includes: a plurality of rotor laminations 1 as in any one of the first aspect embodiments, the plurality of rotor laminations 1 being stacked to form the rotor core 2, and mounting slots 12 of the plurality of rotor laminations 1 forming mounting holes.

[0123] The rotor core 2 provided in the second aspect of the present invention, since it includes the rotor lamination 1 of any of the embodiments in the first aspect, has all the beneficial effects of any of the above embodiments, which will not be repeated here.

[0124] Specifically, mounting slots corresponding to multiple rotor laminations form mounting holes, so that the rotor core has multiple mounting holes spaced apart along the circumference, which are used to insert permanent magnets.

[0125] The rotor provided in the third aspect of the present invention includes: a rotor core 2 as in the second aspect embodiment and a plurality of permanent magnets, which are inserted into the mounting holes of the rotor core 2.

[0126] The rotor provided in the third aspect of the present invention, having the rotor core 2 of the second aspect embodiment, has all the beneficial effects of any of the above embodiments, which will not be repeated here.

[0127] The rotor is a built-in permanent magnet motor rotor.

[0128] Optionally, the permanent magnet has an I-shaped, V-shaped, or U-shaped cross-section perpendicular to the rotor axis.

[0129] The cross-section of the permanent magnet perpendicular to the rotor axis can be I-shaped, V-shaped, or U-shaped, or other shapes, which expands the types of permanent magnets that can be adapted to the rotor core 2 and helps to increase the applicability of the product.

[0130] An embodiment of the fourth aspect of the present invention provides an electric motor, comprising: a rotor and a stator as described in the embodiment of the third aspect, which are fitted together with the rotor.

[0131] The motor provided in the fourth aspect of the present invention, having included the rotor of any of the embodiments in the third aspect, has all the beneficial effects of any of the above embodiments, which will not be repeated here.

[0132] A fifth aspect of the present invention provides a vehicle comprising: a vehicle body and a motor as described in the fourth aspect, the motor being mounted in the vehicle body.

[0133] The vehicle provided by the fifth aspect of the present invention, having included the motor of the fourth aspect embodiment, has all the beneficial effects of any of the above embodiments, which will not be repeated here.

[0134] The following is a specific example, which is compared with a contrasting example.

[0135] Specific example: An 8-pole rotor, wherein the rotor core 2 is formed by stacking multiple rotor laminations 1, and each pole arc region 11 of each rotor lamination 1 has four through holes 13 symmetrically opened, such as... Figure 1 As shown, the through hole 13 is opened at both ends of the polar arc region 11 near the magnetic bridge 14.

[0136] Comparative example: The difference from the specific example above is that the polar arc region 11 of the rotor lamination 1 does not have the aforementioned through hole 13.

[0137] The electromagnetic torque of the specific example and the comparative example were detected, and the results were as follows: Figure 8 The electromagnetic torque waveform comparison diagram shown depicts the torque on the horizontal axis and the rotor position on the vertical axis. (From...) Figure 8 It can be seen that after opening through hole 13, the torque pulsation is effectively reduced and the average torque is increased.

[0138] Therefore, we can conclude that the rotor optimization method provided in this application can effectively weaken the quadrature-axis armature reaction, significantly improve the motor torque pulsation, and also improve the electromagnetic torque of the motor to a certain extent.

[0139] In summary, the rotor lamination provided by this invention optimizes the rotor magnetic field distribution by setting through holes at the ends of the pole arc region near the magnetic isolation bridges on both sides. This effectively weakens the cross-axis armature reaction, significantly improves motor torque pulsation, and also enhances the motor's electromagnetic torque to a certain extent, thus improving the motor's performance. In other words, because the magnetic saturation at the two ends of the pole arc region near the magnetic isolation bridges is higher than that in the middle, it is more prone to magnetic field distortion. Therefore, this solution sets through holes at the two ends of the pole arc region near the magnetic isolation bridges to optimize the magnetic field distribution, thereby improving magnetic field distortion and solving the problem of large torque fluctuations that often occur in motors under high core saturation conditions.

[0140] In this invention, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance; the term "multiple" refers to two or more unless otherwise explicitly defined. The terms "install," "connect," "link," and "fix" should be interpreted broadly. For example, "connect" can be a fixed connection, a detachable connection, or an integral connection; "link" can be a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0141] In the description of this invention, it should be understood that the terms "upper," "lower," "left," "right," "front," "rear," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or unit referred to must have a specific orientation or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0142] In the description of this specification, the terms "one embodiment," "some embodiments," "specific embodiment," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0143] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A rotor lamination, characterized in that, The rotor lamination has multiple mounting slots for mounting permanent magnets. The portion of each mounting slot that is adapted to the permanent magnet defines a pole arc region between itself and the outer periphery of the rotor lamination. Magnetic isolation bridges are provided on both sides of the pole arc region along the circumferential direction of the rotor lamination. The polar arc region is provided with multiple through holes, which are distributed at two ends of the polar arc region near the magnetic isolation bridge. All the through holes in the polar arc region are distributed at circumferential intervals along the rotor laminations and are symmetrically distributed about the center line of the corresponding magnetic poles; Along the direction close to the center line of the corresponding magnetic pole, the dimension of the nth through hole at any of the ends along the length of the mounting groove is denoted as Wn, and the width of the distance between the nth through hole and the (n-1)th through hole is denoted as D. n-1 The dimension of the permanent magnet along the length of the mounting groove is denoted as Wm; Where, 0.15≤2×(W1+W2+…+Wn+D1+D2+…+D n-1 ) / Wm≤0.

35.

2. The rotor lamination according to claim 1, characterized in that, The number of through holes located at any of the said ends is multiple.

3. The rotor lamination according to claim 1, characterized in that, The number of through holes located at any of the said ends is 1 to 4.

4. The rotor lamination according to claim 2, characterized in that, The two ends of the mounting groove are configured as magnetic isolation holes, and the magnetic isolation holes and the outer periphery of the rotor lamination form the magnetic isolation bridge. The minimum distance d between the through hole and the adjacent magnetic isolation bridge and the minimum spacing D between two adjacent through holes located at any of the ends satisfy: d≤k×D, where k∈[0.5,2].

5. The rotor lamination according to claim 2, characterized in that, The minimum spacing D between two adjacent through holes located at any of the ends is greater than or equal to the thickness of the rotor lamination.

6. The rotor lamination according to claim 2, characterized in that, Along the direction close to the centerline of the corresponding magnetic pole, the dimension H of the through hole at any of the ends gradually increases along the width direction of the corresponding mounting groove; and / or Along the direction close to the center line of the corresponding magnetic pole, the dimension W of the through hole located at any of the ends gradually increases along the length direction of the corresponding mounting groove.

7. The rotor lamination according to any one of claims 1 to 6, characterized in that, The dimension H of the through hole along the width direction of the corresponding mounting groove and the dimension W of the through hole along the length direction of the corresponding mounting groove satisfy: 3.5≥(H / W)≥1.

8. The rotor lamination according to any one of claims 1 to 6, characterized in that, The dimension W of the through hole along the length direction of the corresponding mounting groove is greater than or equal to 0.3 mm; and / or The dimension H of the through hole along the width direction of the corresponding mounting groove is greater than or equal to 0.3 mm.

9. The rotor lamination according to any one of claims 1 to 6, characterized in that, The minimum distance Lmin between the through hole and the outer periphery of the rotor lamination is greater than or equal to the thickness of the rotor lamination.

10. The rotor lamination according to any one of claims 1 to 6, characterized in that, The through hole has a notch that penetrates the outer periphery of the rotor lamination; or The through hole has a notch that connects to the corresponding mounting groove; or The through hole is a closed ring.

11. The rotor lamination according to any one of claims 1 to 6, characterized in that, The through-hole is rectangular, circular, elliptical, or a long strip formed by a combination of rectangle and semicircle; and / or The multiple through holes have the same shape.

12. A rotor core, characterized in that, include: A plurality of rotor laminations as described in any one of claims 1 to 11, wherein the plurality of rotor laminations are stacked to form the rotor core, and the mounting slots of the plurality of rotor laminations form mounting holes.

13. A rotor, characterized in that, include: The rotor core as described in claim 12; and Multiple permanent magnets are inserted into the mounting holes of the rotor core.

14. The rotor according to claim 13, characterized in that, The permanent magnet has an I-shaped, V-shaped, or U-shaped cross-section perpendicular to the axis of the rotor.

15. An electric motor, characterized in that, include: The rotor as described in claim 13 or 14; and The stator mates with the rotor assembly.

16. A vehicle, characterized in that, include: Vehicle body; and The motor as described in claim 15 is installed in the vehicle body.

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