Rotor lamination, rotor structure and electric machine

Abstract

This invention relates to the field of motor technology, specifically to a rotor lamination, a rotor structure, and a motor. The first magnet slot of the rotor lamination has a first A air slot section, a first magnet mounting section, and a second A air slot section connected in sequence. The second magnet slot of the rotor lamination has a first B air slot section, a second magnet mounting section, and a second B air slot section connected in sequence. The first A air slot section has a first straight side B12, the second A air slot section has a second straight side B13, the first B air slot section has a third straight side B21, and the second B air slot section has a fourth straight side B22. The length of the first straight side B12 is L. B12 The length of the second straight side B13 is L. B13 The length of the third linear side B21 is L. B21 The length of the fourth linear side B22 is L. B22 , where L B12 = (1~1.1)*L B13 And L B21 = (3.4~3.5)*L B22 And L B13 = (2.1~2.2)*L B22 According to the solution of the present invention, it can reduce motor torque ripple and harmonic content.

Description

Technical Field

[0001] This invention relates to the field of motor technology, and in particular to a rotor lamination, rotor structure, and motor. Background Technology

[0002] In recent years, with the rapid development of power electronics technology and the emergence of various control methods, the control methods of AC motors have become increasingly mature. Permanent magnet synchronous motors, due to their advantages such as small size, light weight, low loss, high efficiency, and reliable operation, are widely used in the electric vehicle field. A permanent magnet motor mainly consists of an external housing and internal structures such as the stator and rotor. Among these, motors using full-pitch windings are advantageous in increasing the harmonic winding coefficient. With the same air gap magnetic flux density distribution, the back electromotive force harmonic amplitude is larger, which is beneficial for increasing the motor torque density by injecting harmonic current.

[0003] Although full-pitch winding synchronous motors have many advantages such as high torque density and high efficiency, they still have some shortcomings, such as high harmonic content, large torque ripple, and large cogging torque. These shortcomings are important factors restricting the development of full-pitch winding synchronous motors. Summary of the Invention

[0004] In view of this, the present invention provides a rotor lamination, a rotor structure and a motor, the main technical problem to be solved is: how to reduce motor torque ripple and harmonic content.

[0005] To achieve the above objectives, the present invention mainly provides the following technical solutions:

[0006] In a first aspect, embodiments of the present invention provide a rotor lamination, wherein the rotor lamination is provided with a first magnet slot group and a second magnet slot group. The first magnet slot group includes two first magnet slots arranged in a first V-shape, and the second magnet slot group includes two second magnet slots arranged in a second V-shape. The openings of both the first and second V-shapes face the outer edge of the rotor lamination, and the second V-shape is located inside the opening of the first V-shape. The first magnet slot has a first A air slot section, a first magnet mounting section, and a second A air slot section connected in sequence, with the first A air slot section closer to the outer edge of the rotor lamination than the second A air slot section. The second magnet slot has a first B air slot section, a second magnet mounting section, and a second B air slot section connected in sequence, with the first B air slot section closer to the outer edge of the rotor lamination than the second B air slot section.

[0007] The first A air trough segment has a first straight side connected to the sidewall of the first magnet mounting segment on the outer side of the first V-shape; the second A air trough segment has a second straight side connected to the sidewall of the first magnet mounting segment; the first B air trough segment has a third straight side connected to the sidewall of the second magnet mounting segment on the outer side of the second V-shape; and the second B air trough segment has a fourth straight side connected to the sidewall of the second magnet mounting segment. The length of the first straight side is L. B12 The length of the second straight side is L. B13 The length of the third straight side is L. B21 The length of the fourth straight side is L. B22 , where L B12 L B13 L B21 L B22 There are constraints:

[0008] L B12 = (1~1.1)*L B13 And L B21 = (3.4~3.5)*L B22 And L B13 =(2.1~2.2)*L B22 .

[0009] In some embodiments, two first magnet slots are symmetrically arranged relative to the first surface L, and two second magnet slots are also symmetrically arranged relative to the first surface L, with the center point of the rotor lamination located on the first surface L.

[0010] In some embodiments, the two first magnet slots are respectively the first A magnet slot and the second A magnet slot, and the two second magnet slots are respectively the first B magnet slot and the second B magnet slot, with the first B magnet slot being closer to the first A magnet slot than the second B magnet slot.

[0011] Among them, a groove is provided on the outer edge of the rotor lamination between the first A magnet slot and the first B magnet slot, and the groove is a first arc-shaped groove.

[0012] In some embodiments, the radius r of the first arcuate groove A3 Satisfy: r A3 =1~1.3mm.

[0013] In some embodiments, when two first magnet slots are symmetrically arranged relative to the first surface L, two second magnet slots are also symmetrically arranged relative to the first surface L, and the center point of the rotor lamination is located on the first surface L, the sidewall of the first A air slot section has a second arc-shaped slot, one end of the second arc-shaped slot is connected to the sidewall of the first magnet mounting section through a fifth straight side, and the fifth straight side is located inside the first V-shape;

[0014] Wherein, the angle between the line O2O connecting the center O2 of the second arc groove and the center point O of the rotor lamination and the first surface L is b, and the angle between the line O1O connecting the center O1 of the groove and the center point O of the rotor lamination and the first surface L is a, a=(0.9~0.94)*b.

[0015] In some embodiments, a first magnetic isolation bridge is formed between the bottoms of the two second A air slots, and a second magnetic isolation bridge is formed between the bottoms of the two second B air slots. The width of the first magnetic isolation bridge is d. D1 The width of the second magnetic bridge is d. D2 , where d D1 / d D2 =2~2.2.

[0016] In some embodiments, both second A air slots have first sidewalls, which are arranged in parallel and form the first magnetic isolation bridge between them. The minimum distance between the line D11 connecting the ends of the two first sidewalls away from the rotor center and the inner edge of the rotor lamination is d1.

[0017] Both second B air slots have second sidewalls, which are arranged in parallel and form the second magnetic isolation bridge between them. The minimum distance between the line D12 connecting the ends of the two second sidewalls away from the rotor center and the inner edge of the rotor lamination is d2.

[0018] The radius of the rotor lamination is R, and there is a constraint relationship between d1, d2 and R: d1 = (0.32 ~ 0.36) * R, and d1 / d2 = 0.7 ~ 0.75.

[0019] In some embodiments, the side of the first A air slot section away from the first magnet mounting section has a sixth straight side and a seventh straight side, the sixth straight side is connected to the end of the first straight side away from the first magnet mounting section, and the sixth straight side forms a third magnetic isolation bridge with the q-axis of the adjacent rotor lamination.

[0020] The seventh straight side is connected to the side of the sixth straight side that is away from the first straight side. The seventh straight side is opposite to the outer edge of the rotor lamination, and a fourth magnetic bridge is formed between the seventh straight side and the outer edge of the rotor lamination.

[0021] In some embodiments, the side of the first B air slot section facing away from the second magnet mounting section has an eighth straight side, which is connected to one end of the third straight side facing away from the second magnet mounting section. The eighth straight side is opposite to the outer edge of the rotor lamination, and a fifth magnetic bridge is formed between the eighth straight side and the outer edge of the rotor lamination.

[0022] Secondly, embodiments of the present invention also provide a rotor structure, which may include any of the rotor laminations described above.

[0023] In some embodiments, a first magnet is inserted into the first magnet mounting section, and a second magnet is inserted into the second magnet mounting section;

[0024] The width of the first magnet is d. C1 Thickness L C1 The width of the second magnet is d. C2 Thickness L C2 There exists a constraint relationship: d C1 = (1.16~1.18)*d C2 And L C2 =(5.4~5.5)*L B22 And L C1 / L C2 =1.5~1.6.

[0025] Thirdly, embodiments of the present invention also provide an electric motor, which may include any of the rotor structures described above.

[0026] By employing the above technical solutions, the rotor laminations, rotor structure, and motor of the present invention have at least the following beneficial effects:

[0027] 1. By designing the magnet slot, the position of the first magnet in the first magnet slot can be optimized, and the position of the second magnet in the second magnet slot can also be optimized. Compared with the prior art, the present invention can reduce motor torque pulsation, increase motor output torque, and improve motor performance through the design and optimization of the magnet slot.

[0028] 2. By designing the outer edge of the rotor laminations, the arc-shaped groove A3 is positioned near the first magnet slot. This ensures the motor's output torque while reducing cogging torque, thus resolving the flat-top wave problem of the motor's no-load back EMF and making the back EMF waveform sinusoidal. The better the sinusoidal nature of the motor's back EMF waveform and the lower the harmonic content, the better the motor's performance.

[0029] 3. By designing the magnetic bridge, the first and second magnet slots are brought closer to the inner edge of the rotor, which helps to improve the motor output torque and reduce torque pulsation and harmonic content.

[0030] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, the preferred embodiments of the present invention are described in detail below with reference to the accompanying drawings. Attached Figure Description

[0031] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0032] Figure 1 This is a schematic diagram of the assembly of a rotor lamination and a magnet according to an embodiment of the present invention;

[0033] Figure 2 This is a partial structural diagram of the rotor lamination;

[0034] Figure 3 This is a schematic diagram showing the location of the groove A3 on the outer edge of the rotor lamination;

[0035] Figure 4 yes Figure 3 Enlarged view of point A in the middle;

[0036] Figure 5a The back EMF waveform of the motor is shown after the outer edge of the rotor lamination is modified using the method of the present invention.

[0037] Figure 5b This is a comparison diagram of the back EMF waveforms of motors that have not undergone rotor lamination edge trimming;

[0038] Figure 6 This is a schematic diagram showing the distance between the magnetic isolation bridge and the inner edge of the rotor lamination;

[0039] Figure 7 yes Figure 6 Enlarged view of point A in the middle;

[0040] Figure 8a The following is a waveform diagram showing the output torque of the motor before optimization as a function of time;

[0041] Figure 8b The present invention demonstrates how L can be made using the solution of the present invention. B12 = (1~1.1)*L B13 And L B21 = (3.4~3.5)*L B22 And L B13 =(2.1~2.2)*L B22 Waveform of the motor's output torque over time;

[0042] Figure 9a To optimize the waveform of the back EMF of the front motor over time;

[0043] Figure 9bTo achieve the desired effect using the solution of this invention, the radius r of the first arc-shaped groove is... A3 Waveform of the back EMF of the motor changing over time when the setting is 1~1.3mm;

[0044] Figure 10a To optimize the stress contour plot of the front rotor;

[0045] Figure 10b The stress cloud diagram of the rotor when dD1 / dD2 = 2 to 2.2 is obtained by using the scheme of the present invention;

[0046] Figure 11a The following is a waveform diagram showing the output torque of the motor before optimization as a function of time;

[0047] Figure 11b The diagram shows the waveform of the motor's output torque over time when d1 = (0.32~0.36)*R and d1 / d2 = 0.7~0.75 using the scheme of the present invention.

[0048] Figure 12a The following is a waveform diagram showing the output torque of the motor before optimization as a function of time;

[0049] Figure 12b The present invention demonstrates how the solution employing the present invention enables d C1 = (1.16~1.18)*d C2 And L C2 =(5.4~5.5)*L B22 And L C1 / L C2 Waveform of motor output torque changing with time when =1.5~1.6.

[0050] Reference numerals: 1. First magnet slot; 2. Second magnet slot; 11. First A air slot section; 12. First magnet mounting section; 13. Second A air slot section; 21. First B air slot section; 22. Second magnet mounting section; 23. Second B air slot section; 31. First positioning angle; 32. Second positioning angle; 33. Third positioning angle; 34. Fourth positioning angle; 10. First V-shape; 20. Second V-shape; 131. First sidewall; 231. Second sidewall; 100. Rotor lamination; 111. Fifth straight side; 101. First A magnet slot; 102. Second A magnet slot; 201. First B magnet slot; 202. Second B magnet slot. Detailed Implementation

[0051] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0052] It should be noted that if the embodiments of the present invention involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicators will also change accordingly.

[0053] Furthermore, if the embodiments of this invention involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. If the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0054] like Figure 1 As shown, an embodiment of the present invention provides a rotor lamination 100, which has a first magnet slot group and a second magnet slot group. The first magnet slot group includes two first magnet slots 1 arranged in a first V-shape 10. Both first magnet slots 1 can be strip slots, preferably both are straight slots. The second magnet slot group includes two second magnet slots 2 arranged in a second V-shape 20. Both second magnet slots 2 can be strip slots, preferably both are straight slots. The openings of both the first V-shape 10 and the second V-shape 20 face the outer edge A1 of the rotor lamination 100, and the second V-shape 20 is located inside the opening of the first V-shape 10. It should be noted that the two first magnet slots 1 are not connected at the bottom of the first V-shape 10, and the two first magnet slots 1 have a magnetic isolation bridge at the bottom of the first V-shape 10. Similarly, the two second magnet slots 2 are not connected at the bottom of the second V-shape 20, and the two second magnet slots 2 have another magnetic bridge at the bottom of the second V-shape 20. Those skilled in the art will understand that this V-shaped structure, which is not connected at the bottom, is conventionally referred to as a V-shaped structure. The aforementioned first V-shape 10 and second V-shape 20 cooperate to form a double V-shaped topology of the rotor lamination 100.

[0055] like Figure 1 As shown, the first magnet slot 1 has a first A air slot section 11, a first magnet mounting section 12, and a second A air slot section 13 connected in sequence. The first A air slot section 11 is closer to the outer edge A1 of the rotor lamination relative to the second A air slot section 13. The second magnet slot 2 has a first B air slot section 21, a second magnet mounting section 22, and a second B air slot section 23 connected in sequence. The first B air slot section 21 is closer to the outer edge A1 of the rotor lamination relative to the second B air slot section 23.

[0056] Among them, such as Figure 2 As shown, the first A air groove section 11, located outside the first V-shape 10, has a first straight side B12 connected to the sidewall of the first magnet mounting section 12. The side of the first magnet mounting section 12 closest to the first straight side B12 may have a first positioning angle 31, and the first straight side B12 may be connected to the sidewall of the first positioning angle 31. The first positioning angle 31 is used to engage and position one corner of the first magnet C1. The second A air groove section 13 has a second straight side B13 connected to the sidewall of the first magnet mounting section 12. The side of the first magnet mounting section 12 closest to the second straight side B13 may have a second positioning angle 32, and the second straight side B13 may be connected to the sidewall of the second positioning angle 32. The second positioning angle 32 is used to engage and position the other corner of the first magnet C1. The first B air groove section 21, located outside the second V-shape 20, has a third straight side B21 that connects to the sidewall of the second magnet mounting section 22. The side of the second magnet mounting section 22 closest to the third straight side B21 may have a third positioning angle 33, which connects to the sidewall of the third positioning angle 33. The third positioning angle 33 is used to engage and position one corner of the second magnet C2. The second B air groove section 23 has a fourth straight side B22 that connects to the sidewall of the second magnet mounting section 22. The side of the second magnet mounting section 22 closest to the fourth straight side B22 may have a fourth positioning angle 34, which connects to the sidewall of the fourth positioning angle 34. The fourth positioning angle 34 is used to engage and position the other corner of the second magnet C2.

[0057] like Figure 2 As shown, the length of the aforementioned first linear side B12 is L. B12 The length of the second straight side B13 is L. B13 The length of the third linear side B21 is L. B21 The length of the fourth linear side B22 is L. B22 , where L B12 L B13 L B21 L B22 There is a constraint relationship: LB12 = (1~1.1)*L B13 And L B21 = (3.4~3.5)*L B22 And L B13 =(2.1~2.2)*L B22 Preferably, L B12 =1.05*L B13 L B21 =3.45*L B22 L B13 =2.15*L B22 .

[0058] In the example above, L B12 L B13 L B21 L B22 The positions of the first magnet C1 and the second magnet C2 in the second magnet slot 2 are determined. According to the optimization results, when the magnets approach the bottom of the magnet slot (i.e., the end closest to the center of the rotor lamination 100), the motor torque pulsation increases; when the magnets approach the top of the magnet slot (i.e., the end furthest from the center of the rotor lamination 100), the motor output torque decreases. In the example above, by making L... B12 = (1~1.1)*L B13 And L B21 = (3.4~3.5)*L B22 And L B13 =(2.1~2.2)*L B22 This allows the first magnet C1 to be in the optimal position in the first magnet slot 1, and the second magnet C2 to be in the optimal position in the second magnet slot 2. At this point, the motor torque ripple and output torque are optimized, maximizing the reduction of motor torque ripple, increasing motor output torque, and improving motor performance. Among these, Figure 8a The following is a waveform diagram showing the output torque of the motor before optimization as a function of time. Figure 8b The present invention demonstrates how L can be made using the solution of the present invention. B12 = (1~1.1)*L B13 And L B21 = (3.4~3.5)*L B22 And L B13 =(2.1~2.2)*L B22 The waveform diagram of the motor's output torque changing over time. Figure 8a and Figure 8b The comparison shows that after optimization using the solution of the present invention, the output torque of the motor increased from 269 Nm to 273 Nm, and the torque ripple of the motor decreased from 9.8% to 7.7%.

[0059] like Figure 1As shown, the two first magnet slots 1 can be symmetrically arranged relative to the first surface L, and the two second magnet slots 2 can also be symmetrically arranged relative to the first surface L, and the center point of the rotor lamination is located on the first surface L.

[0060] In the above example, by making the two first magnet slots 1 and the two second magnet slots 2 symmetrical about the same plane, the force on the rotor lamination 100 is more balanced, which is beneficial to improving the magnetic balance on the rotor lamination 100.

[0061] like Figure 3 As shown, the two first magnet slots 1 can be the first A magnet slot 101 and the second A magnet slot 102, respectively. The two second magnet slots 2 can be the first B magnet slot 201 and the second B magnet slot 202, respectively. The first B magnet slot 201 is closer to the first A magnet slot 101 than the second B magnet slot 202. In a specific application example, the first A magnet slot 101 and the first B magnet slot 201 are located on one side of the aforementioned first surface L, and the second A magnet slot 102 and the second B magnet slot 202 are located on the other side of the aforementioned first surface L.

[0062] Among them, such as Figure 4 As shown, a groove A3 is provided on the outer edge A1 of the rotor lamination 100 between the first A magnet slot 101 and the first B magnet slot 201. The groove A3 is a first arc-shaped groove.

[0063] In the above example, since the distribution of magnetic field lines near the magnet slot can affect the change in the back electromotive force waveform, setting a groove A3 near it can adjust the distribution of magnetic field lines, thereby changing the harmonic content of the waveform. Compared with the prior art, which sets the groove as a triangle or other shape with corners, although it can reduce the cogging torque, it will lead to an increase in torque pulsation. However, the present invention sets the groove A3 as an arc-shaped groove, which does not lead to an increase in torque pulsation and is easier to process than a triangular groove.

[0064] In a specific application example, the radius r of the first arc-shaped groove mentioned above A3 Satisfy: r A3 =1~1.3mm. Preferably, r A3 =1.15mm. Wherein, the radius r of the first arc-shaped groove... A3 An excessively large radius will increase cogging torque, while an excessively small radius will negate its harmonic optimization function. By adjusting the radius r of the first arc-shaped groove... A3 The diameter is set to 1~1.3mm, so that the rotor lamination 100 of the present invention can both optimize harmonics and avoid increasing cogging torque. Figure 9a To optimize the waveform of the back EMF of the front motor over time. Figure 9b To achieve the desired effect using the solution of this invention, the radius r of the first arc-shaped groove is... A3The waveform of the motor's back EMF changing over time when the setting is 1~1.3mm is shown in the figure. Figure 9a and Figure 9b The comparison shows that after optimization using the solution of the present invention, the harmonic content of the motor can be reduced from 9.3% to 5.8%.

[0065] like Figure 4 As shown, the sidewall of the aforementioned groove A3 and the outer edge A1 of the rotor lamination 100 are transitioned by a circular arc A2. This avoids the influence of sharp corners on motor torque pulsation, which helps to reduce motor torque pulsation and improve motor performance.

[0066] like Figure 3 and Figure 4 As shown, when the two first magnet slots 1 are symmetrically arranged relative to the first surface, and the two second magnet slots 2 are also symmetrically arranged relative to the first surface, and the center of the rotor lamination 100 is located on the first surface L, the sidewall of the first A air slot section 11 has a second arc-shaped slot B11. One end of the second arc-shaped slot B11 is connected to the sidewall of the first magnet mounting section 12 through a fifth straight side 111, which is located inside the first V-shape 10. The fifth straight side 111 can be located in the same plane as the sidewall of the first magnet mounting section 12 for easy processing.

[0067] like Figure 3 As shown, the angle between the line O2O connecting the center O2 of the aforementioned second arc-shaped groove B11 and the center point O of the rotor lamination 100 and the first surface L is b, and the angle between the line O1O connecting the center O1 of the groove A3 and the center point O of the rotor lamination 100 and the first surface L is a, where a = (0.9~0.94)*b. Preferably, a = 0.92*b.

[0068] In the above example, by setting a = (0.9~0.94)*b, this constraint ensures that groove A3 is located near the first magnet slot 1. This guarantees the motor's output torque while reducing the motor's cogging torque, solving the problem of the flat-top wave in the motor's no-load back EMF and making the motor's back EMF waveform sinusoidal. The better the sinusoidal nature of the motor's back EMF waveform, the lower the harmonic content, and the better the motor's performance. The poor sinusoidal nature and high harmonic content of the flat-top wave are problems that need to be overcome. This invention, through the aforementioned constraint, ensures a better sinusoidal nature of the motor's back EMF waveform.

[0069] in, Figure 5a The back EMF waveform of the motor is obtained by modifying the outer edge of the rotor lamination 100 to make the groove A3 on the outer edge of the rotor lamination 100 an arc-shaped groove, and making the position of the groove A3 satisfy a=(0.9~0.94)*b. Figure 5b This is a comparison diagram of the back EMF waveforms of a motor that has not undergone rotor lamination 100 outer edge trimming. Figure 5aand Figure 5b Both axes represent time on the x-axis and the motor's back electromotive force on the y-axis. (From...) Figure 5b It can be seen that the back EMF waveform of the motor in the existing technology is a flat-topped wave. From... Figure 5a It can be seen that after the outer edge of the rotor lamination 100 is modified and optimized using the solution of the present invention, the back EMF waveform of the motor is optimized from a flat-top wave to a sine wave, which can effectively reduce the harmonic content of the motor and improve the performance of the motor.

[0070] like Figure 6 As shown, a first magnetic isolation bridge D1 is formed between the bottoms of the two second A air slot sections 13. A second magnetic isolation bridge D2 is formed between the bottoms of the two second B air slot sections 23. The width of the first magnetic isolation bridge D1 is d. D1 The width of the second magnetic bridge D2 is d. D2 , where d D1 / d D2 =2~2.2. Preferably, d D1 / d D2 =2.1.

[0071] In the example above, because the first magnetic bridge D1 is close to the motor shaft, the rotor stress is greater, and it bears more stress than the second magnetic bridge D2. This constraint makes the thickness of the first magnetic bridge D1 greater than that of the second magnetic bridge D2. This strengthens the rotor strength at the first magnetic bridge D1 while also constraining the decrease in output torque caused by the excessive width of the first magnetic bridge D1. Therefore, this constraint allows the motor to maintain output torque while increasing rotor strength, meeting the requirements for high-speed motor operation. Figure 10a To optimize the stress contour plot of the front rotor, Figure 10b To obtain the stress cloud diagram of the rotor when dD1 / dD2 = 2~2.2 using the scheme of the present invention, from Figure 10a and Figure 10b The comparison shows that after optimization using the scheme of the present invention, the maximum stress of the rotor is reduced from 314MPa to 224MPa.

[0072] In a specific application example, the aforementioned d D2 =0.7~0.8mm, preferably d D2 =0.8mm, which can reduce magnetic leakage.

[0073] like Figure 7As shown, both of the aforementioned second A air slot sections 13 have first sidewalls 131, which are arranged in parallel and form the aforementioned first magnetic isolation bridge D1 between them. The distance between the line D11 connecting the ends of the two first sidewalls 131 away from the rotor center and the inner edge A5 of the rotor lamination is d1. It should be noted that: the connecting line D11 is a straight line segment, the inner edge A5 of the rotor lamination is an arc segment, and the inner edge A5 of the rotor lamination has a first straight line M tangent to it. This first straight line M is parallel to the connecting line D11, and the distance between the connecting line D11 and the inner edge A5 of the rotor lamination refers to the distance between the connecting line D11 and the first straight line M (e.g., ...). Figure 6 (As shown).

[0074] like Figure 7 As shown, both of the aforementioned second B air slot sections 23 have second sidewalls 231, which are arranged in parallel and form the aforementioned second magnetic isolation bridge D2 between them. The distance between the line D12 connecting the ends of the two second sidewalls 231 away from the rotor center and the inner edge A5 of the rotor lamination is d2. It should be noted that: the connecting line D12 is a straight line segment, the inner edge A5 of the rotor lamination is an arc segment, and the inner edge A5 of the rotor lamination has a first straight line M tangent to it. This first straight line M is also parallel to the connecting line D12. The distance between the connecting line D12 and the inner edge A5 of the rotor lamination refers to the distance between the connecting line D12 and the first straight line M (e.g., ...). Figure 6 (As shown).

[0075] The radius of the rotor lamination 100 is R, and there is a constraint relationship between d1, d2 and R: d1 = (0.32~0.36)*R, and d1 / d2 = 0.7~0.75. Preferably, d1 = 0.34*R, and d1 / d2 = 0.725.

[0076] In the above example, the constraint relationship between d1, d2, and R allows the first magnet slot 1 and the second magnet slot 2 to approach the inner edge A5 of the rotor lamination 100. Simulation results show that when the magnet slots are close to the inner edge of the rotor, the motor output torque increases, but torque ripple and harmonic content also increase. This constraint relationship optimizes the motor's performance, improving output torque while reducing torque ripple and harmonic content. Figure 11a The following is a waveform diagram showing the output torque of the motor before optimization as a function of time. Figure 11b The diagram shows the waveform of the motor's output torque over time when d1 = (0.32~0.36)*R and d1 / d2 = 0.7~0.75 using the scheme of the present invention. Figure 11a and Figure 11b The comparison shows that after optimization using the solution of the present invention, the output torque of the motor increased from 273 Nm to 275 Nm, and the torque ripple of the motor decreased from 7.7% to 5.6%.

[0077] like Figure 2 As shown, the first A air slot section 11, on the side facing away from the first magnet mounting section 12, has a sixth straight side B14 and a seventh straight side B15. The sixth straight side B14 is connected to one end of the first straight side B12 facing away from the first magnet mounting section 12. Preferably, the sixth straight side B14 and the end of the first straight side B12 facing away from the first magnet mounting section 12 are connected by an arc transition. The sixth straight side B14 forms a third magnetic isolation bridge D3 with the q-axis of the adjacent rotor lamination to prevent magnetic leakage. The sixth straight side B14 can be parallel to the q-axis of the adjacent rotor lamination to improve the magnetic isolation effect.

[0078] The aforementioned seventh straight side B15 connects to the side of the sixth straight side B14 that is away from the first straight side B12. Preferably, the seventh straight side B15 and the side of the sixth straight side B14 that is away from the first straight side B12 are transitioned by an arc. The seventh straight side B15 is opposite to the outer edge A1 of the rotor lamination, and a fourth magnetic isolation bridge D4 is formed between the seventh straight side B15 and the outer edge A1 of the rotor lamination to prevent magnetic leakage. The seventh straight side B15 can be parallel to a second straight line that is tangent to the outer edge A1 of the rotor lamination, which further improves the magnetic isolation effect.

[0079] like Figure 2 As shown, the first B air slot section 21 has an eighth straight side B23 on the side facing away from the second magnet mounting section 22. The eighth straight side B23 is connected to one end of the third straight side B21 facing away from the second magnet mounting section 22. Preferably, the eighth straight side B23 and the end of the third straight side B21 facing away from the second magnet mounting section 22 are transitioned by an arc. The eighth straight side B23 is opposite to the outer edge A1 of the rotor lamination, and a fifth magnetic isolation bridge D5 is formed between the eighth straight side B23 and the outer edge A1 of the rotor lamination to prevent magnetic leakage. The eighth straight side B23 can be parallel to the third straight line, which is tangent to the outer edge A1 of the rotor lamination, thus further improving the magnetic isolation effect.

[0080] One embodiment of the present invention also proposes a rotor structure, which may include any of the rotor laminations 100 described above. In this example, because the rotor structure adopts the rotor laminations 100 described above, the position of the first magnet C1 in the first magnet slot 1 can be optimized, and the position of the second magnet C2 in the second magnet slot 2 can be optimized. Compared with the prior art, the present invention can reduce motor torque ripple, increase motor output torque, and improve motor performance through the design and optimization of the magnet slots.

[0081] like Figure 1As shown, a first magnet C1 is inserted into the first magnet mounting section 12, and a second magnet C2 is inserted into the second magnet mounting section 22. The width of the first magnet C1 is d. C1 The thickness of the first magnet C1 is L. C1 The width of the second magnet C2 is d. C2 The thickness of the second magnet C2 is L. C2 There exists a constraint relationship: d C1 = (1.16~1.18)*d C2 And L C2 =(5.4~5.5)*L B22 And L C1 / L C2 =1.5~1.6. Preferably, d C1 =1.17*d C2 And L C2 =5.45*L B22 And L C1 / L C2 =1.55.

[0082] In the above example, the width and thickness of the double V-shaped magnets have a significant impact on the motor's performance. Since demagnetization is prone to occur at the outer magnet (i.e., the first magnet C1), leading to a decrease in output torque, the aforementioned constraints ensure that the thickness of the first magnet C1 is greater than the thickness of the second magnet C2, and that the width of the first magnet C1 is greater than the width of the second magnet C2. This helps to suppress demagnetization at the first magnet C1, increasing the motor's output torque. Simultaneously, the constraints on the size and ratio of the first magnet C1 and the second magnet C2 minimize the motor's torque ripple and cogging torque, thus achieving the advantages of increasing the motor's output torque while reducing cogging torque and torque ripple. Figure 12a The following is a waveform diagram showing the output torque of the motor before optimization as a function of time. Figure 12b The present invention demonstrates how the solution employing the present invention enables d C1 = (1.16~1.18)*d C2 And L C2 =(5.4~5.5)*L B22 And L C1 / L C2 The waveform diagram of the motor's output torque versus time when the torque is between 1.5 and 1.6. Figure 12a and Figure 12b The comparison shows that after optimization using the solution of the present invention, the output torque of the motor increased from 275Nm to 277Nm, and the torque ripple of the motor decreased from 5.6% to 3.1%.

[0083] One embodiment of the present invention also proposes an electric motor, which may include any of the rotor structures described above. In this example, because the motor adopts the aforementioned rotor structure, the position of the first magnet C1 in the first magnet slot 1 can be optimized, and the position of the second magnet C2 in the second magnet slot 2 can be optimized. Compared with the prior art, the present invention, through the design and optimization of the magnet slots, can reduce motor torque ripple, increase motor output torque, and improve motor performance.

[0084] For ease of understanding, the overall structure of the present invention will be described below, and its working principle will be explained.

[0085] This invention relates to the design of a rotor lamination 100. Starting with the design of the dimensions and shape of the double V-shaped topology on the rotor lamination 100, and through the design and optimization of the first magnet slot 1 and the second magnet slot 2 on the rotor lamination 100, that is, by rationally adjusting the installation positions of the first magnet C1 and the second magnet C2, L... B12 = (1~1.1)*L B13 And L B21 = (3.4~3.5)*L B22 And L B13 =(2.1~2.2)*L B22 This can reduce motor torque ripple and harmonic content; furthermore, by designing the outer edge shape of the rotor lamination 100, specifically by providing an arc-shaped groove A3 on the outer edge of the rotor lamination 100 and defining its position, r A3 =1~1.3mm, and a=(0.9~0.94)*b, which can reduce harmonic content and cogging torque, and improve waveform sinusoidality; in addition, by optimizing the dimensions of the first magnetic isolation bridge D1 and the second magnetic isolation bridge D2, d D1 / d D2 =2~2.2, and d1=(0.32~0.36)*R, and d1 / d2=0.7~0.75, which can improve the output torque of the motor and reduce the stress at the rotor magnetic bridge.

[0086] Furthermore, through the design and optimization of the first magnet slot 1 and the second magnet slot 2 on the rotor lamination 100, and through the design of the outer edge shape of the rotor lamination 100, and through the optimization of the dimensions of the first magnetic isolation bridge D1 and the second magnetic isolation bridge D2, the L... B12 = (1~1.1)*L B13 And L B21 = (3.4~3.5)*L B22 And L B13 =(2.1~2.2)*L B22 And make r A3 =1~1.3mm, and a=(0.9~0.94)*b, and make d D1 / dD2 =2~2.2, and d1=(0.32~0.36)*R, and d1 / d2=0.7~0.75. The final overall beneficial effect is as follows: such as 5a and Figure 5b As shown, under the condition of ensuring output torque and rotor strength, the harmonic content of the motor can be reduced from 9.3% to 2.8%, which can greatly reduce the harmonic content of the motor and significantly improve the performance of the motor.

[0087] The above description is merely a preferred embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural transformations made using the contents of the present invention's specification and drawings under the inventive concept of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A rotor lamination, characterized in that, The rotor lamination (100) is provided with a first magnetic slot group and a second magnetic slot group. The first magnetic slot group includes two first magnetic slots (1) arranged in a first V-shape (10), and the second magnetic slot group includes two second magnetic slots (2) arranged in a second V-shape (20). The openings of both the first V-shape (10) and the second V-shape (20) face the outer edge (A1) of the rotor lamination, and the second V-shape (20) is located inside the opening of the first V-shape (10). The first magnetic slot (1) has a... The first A air slot section (11), the first magnet mounting section (12), and the second A air slot section (13) are connected in sequence. The first A air slot section (11) is closer to the outer edge (A1) of the rotor lamination than the second A air slot section (13). The second magnet slot (2) has a first B air slot section (21), a second magnet mounting section (22), and a second B air slot section (23) connected in sequence. The first B air slot section (21) is closer to the outer edge (A1) of the rotor lamination than the second B air slot section (23). The first A air trough section (11) has a first straight side (B12) connected to the side wall of the first magnet mounting section (12) on the outer side of the first V-shape (10); the second A air trough section (13) has a second straight side (B13) connected to the side wall of the first magnet mounting section (12); the first B air trough section (21) has a third straight side (B21) connected to the side wall of the second magnet mounting section (22) on the outer side of the second V-shape (20); and the second B air trough section (23) has a fourth straight side (B22) connected to the side wall of the second magnet mounting section (22); the length of the first straight side (B12) is L. B12 The length of the second straight side (B13) is L. B13 The length of the third linear side (B21) is L. B21 The length of the fourth linear side (B22) is L. B22 , where L B12 L B13 L B21 L B22 There are constraints: L B12 = (1~1.1)*L B13 And L B21 = (3.4~3.5)*L B22 And L B13 =(2.1~2.2)*L B22 .

2. The rotor lamination as described in claim 1, characterized in that, Two first magnet slots (1) are symmetrically arranged relative to the first surface L, and two second magnet slots (2) are also symmetrically arranged relative to the first surface L, and the center point of the rotor lamination (100) is located on the first surface L.

3. The rotor lamination as described in claim 1 or 2, characterized in that, The two first magnet slots (1) are the first A magnet slot (101) and the second A magnet slot (102) respectively, and the two second magnet slots (2) are the first B magnet slot (201) and the second B magnet slot (202) respectively. The first B magnet slot (201) is closer to the first A magnet slot (101) relative to the second B magnet slot (202). Among them, a groove (A3) is provided on the outer edge of the rotor lamination between the first A magnet slot (101) and the first B magnet slot (201), and the groove (A3) is a first arc-shaped groove.

4. The rotor lamination as described in claim 3, characterized in that, The radius r of the first arc-shaped groove A3 Satisfy: r A3 =1~1.3mm.

5. The rotor lamination as described in claim 4, characterized in that, When two first magnet slots (1) are symmetrically arranged relative to the first surface L, and two second magnet slots (2) are also symmetrically arranged relative to the first surface L, and the center point of the rotor lamination (100) is located on the first surface L, the side wall of the first A air slot section (11) has a second arc-shaped slot (B11), one end of the second arc-shaped slot (B11) is connected to the side wall of the first magnet mounting section (12) through the fifth straight side (111), and the fifth straight side (111) is located inside the first V-shape (10); Wherein, the angle between the line O2O connecting the center O2 of the second arc groove (B11) and the center point O of the rotor lamination (100) and the first surface L is b, and the angle between the line O1O connecting the center O1 of the groove (A3) and the center point O of the rotor lamination and the first surface L is a, a=(0.9~0.94)*b.

6. The rotor lamination as described in claim 1, 2, 4 or 5, characterized in that, A first magnetic isolation bridge (D1) is formed between the bottoms of the two second A air slot sections (13), and a second magnetic isolation bridge (D2) is formed between the bottoms of the two second B air slot sections (23). The width of the first magnetic isolation bridge (D1) is d. D1 The width of the second magnetic bridge (D2) is d. D2 , where d D1 / d D2 =2~2.

2.

7. The rotor lamination as described in claim 6, characterized in that, Both second A air slot sections (13) have first sidewalls (131), which are arranged in parallel and form the first magnetic isolation bridge (D1) between them. The minimum distance between the line D11 connecting the two first sidewalls (131) away from the rotor center and the inner edge (A5) of the rotor lamination is d1. Both second B air slot sections (23) have second sidewalls (231), which are arranged in parallel and form the second magnetic isolation bridge (D2) between them. The minimum distance between the line D12 connecting the two second sidewalls (231) away from the rotor center and the inner edge (A5) of the rotor lamination is d2. The radius of the rotor lamination is R, and there is a constraint relationship between d1, d2 and R: d1 = (0.32 ~ 0.36) * R, and d1 / d2 = 0.7 ~ 0.

75.

8. The rotor lamination as described in claim 1, 2, 4, 5 or 7, characterized in that, The first A air slot section (11) has a sixth straight side (B14) and a seventh straight side (B15) on the side away from the first magnet mounting section (12). The sixth straight side (B14) is connected to the end of the first straight side (B12) away from the first magnet mounting section (12). The sixth straight side (B14) forms a third magnetic isolation bridge (D3) between the sixth straight side (B14) and the q-axis of the adjacent rotor lamination. The seventh straight side (B15) is connected to the side of the sixth straight side (B14) that is away from the first straight side (B12). The seventh straight side (B15) is opposite to the outer edge (A1) of the rotor lamination (100), and a fourth magnetic bridge (D4) is formed between the seventh straight side (B15) and the outer edge (A1) of the rotor lamination (100).

9. The rotor lamination as described in claim 1, 2, 4, 5 or 7, characterized in that, The first B air slot section (21) has an eighth straight side (B23) on the side away from the second magnet mounting section (22). The eighth straight side (B23) is connected to the end of the third straight side (B21) away from the second magnet mounting section (22). The eighth straight side (B23) is opposite to the outer edge (A1) of the rotor lamination, and a fifth magnetic bridge (D5) is formed between the eighth straight side (B23) and the outer edge (A1) of the rotor lamination.

10. A rotor structure, characterized in that, The rotor laminations include any one of claims 1 to 9.

11. The rotor structure as described in claim 10, characterized in that, A first magnet (C1) is inserted into the first magnet mounting section (12), and a second magnet (C2) is inserted into the second magnet mounting section (22); The width of the first magnet (C1) is d C1 Thickness L C1 The width of the second magnet (C2) is d. C2 Thickness L C2 There exists a constraint relationship: d C1 = (1.16~1.18)*d C2 And L C2 =(5.4~5.5)*L B22 And L C1 / L C2 =1.5~1.

6.

12. An electric motor, characterized in that, Includes the rotor structure described in claim 10 or 11.

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