Rotor structure of permanent magnet synchronous motor, permanent magnet synchronous motor and compressor

Abstract

The invention provides a rotor structure of a permanent magnet synchronous motor, the permanent magnet synchronous motor and a compressor, the rotor structure of the permanent magnet synchronous motor comprises a rotor core and a permanent magnet, in the same magnetic pole, the rotor core is provided with a first magnetic isolation hole and a second magnetic isolation hole, the first magnetic isolation holes and the second magnetic isolation holes are located between the permanent magnet grooves and the rotor outer circle of the rotor iron core. The first magnetic isolation hole comprises a first magnetic isolation hole I and a first magnetic isolation hole II, and the minimum width of the first magnetic isolation hole I is smaller than the minimum width of the first magnetic isolation hole II in the circumferential direction of the rotor iron core; the second magnetic isolation holes comprise the first second magnetic isolation holes and the second second magnetic isolation holes, the first second magnetic isolation holes are relatively close to the outer circle of the rotor, the second magnetic isolation holes are relatively close to the permanent magnet grooves, and at least one bent magnetic isolation bridge is formed between the second magnetic isolation holes and the first magnetic isolation holes. According to the permanent magnet synchronous motor, the problems of high air gap flux density waveform distortion rate and large harmonic proportion of the permanent magnet synchronous motor in the prior art can be solved.

Description

Technical Field

[0001] The present invention relates to the technical field of motors, and in particular to a rotor structure of a permanent magnet synchronous motor, a permanent magnet synchronous motor and a compressor. Background Art

[0002] Permanent magnet motors rely on permanent magnets to generate the main magnetic field. Compared with ordinary induction motors, permanent magnet synchronous motors do not require reactive excitation current, and the rotor resistance loss is zero in the synchronous operation state. Therefore, they have the characteristics of high power factor and high efficiency, and can usually be used to replace induction motors with lower power energy indicators. Their economic and social benefits are very significant, and they are widely used in various industries.

[0003] However, the permanent magnet material of the permanent magnet synchronous motor, the permanent magnet of fixed brand and material has a constant magnetic energy product, and the motor air gap magnetic field is difficult to adjust. At the same time, the motor's slot structure makes the air gap magnetic density and back electromotive force have a large harmonic content, and the motor's electromagnetic force peak is large, resulting in large motor torque pulsation and vibration noise.

[0004] Since the permanent magnet synchronous motor in the prior art has technical problems such as high air gap magnetic flux waveform distortion rate and large harmonic proportion, the present invention studies and designs a rotor structure of a permanent magnet synchronous motor, a permanent magnet synchronous motor and a compressor. Summary of the Invention

[0005] Therefore, the technical problem to be solved by the present invention is to overcome the defects of the permanent magnet synchronous motor in the prior art, such as high air gap magnetic flux waveform distortion rate and large harmonic proportion, thereby providing a rotor structure of a permanent magnet synchronous motor, a permanent magnet synchronous motor and a compressor.

[0006] In order to solve the above problems, the present invention provides a rotor structure of a permanent magnet synchronous motor, which includes:

[0007] A rotor core and a permanent magnet, wherein the rotor core has a permanent magnet slot for accommodating the permanent magnet, and in the same magnetic pole, the rotor core has a first magnetic isolation hole and a second magnetic isolation hole, wherein the first magnetic isolation hole and the second magnetic isolation hole are both located between the permanent magnet slot and the rotor outer circle of the rotor core;

[0008] The first magnetic isolation hole includes a first magnetic isolation hole 1 and a first magnetic isolation hole 2, both of which are hole structures and are interconnected, the first magnetic isolation hole 1 is relatively close to the outer circle of the rotor, the first magnetic isolation hole 2 is relatively close to the permanent magnet slot, and the minimum width of the first magnetic isolation hole 1 along the circumferential direction of the rotor core is smaller than the minimum width of the first magnetic isolation hole 2;

[0009] The second magnetic isolation hole is located between at least part of the structure of the first magnetic isolation hole and the outer circle of the rotor; the second magnetic isolation hole includes a second magnetic isolation hole one and a second magnetic isolation hole two, the second magnetic isolation hole one and the second magnetic isolation hole two are both hole structures and are interconnected, the second magnetic isolation hole one is relatively close to the outer circle of the rotor, the second magnetic isolation hole two is relatively close to the permanent magnet slot, and at least a bent magnetic isolation bridge is formed between the second magnetic isolation hole and the first magnetic isolation hole.

[0010] In some embodiments,

[0011] In the plane where the axial end face of the rotor core is located, the first magnetic isolation hole 1 is a rectangular hole, and the first magnetic isolation hole 2 is a trapezoidal hole. The rectangular hole includes a parallel first short side 1 and a first short side 2, and the rectangular hole also includes a parallel first long side and a second long side. The trapezoidal hole includes a parallel second short side and a second long side. Along the radial direction of the rotor core, the first short side 1 of the rectangular hole is located radially outside the first short side 2 and opposite to the outer circle of the rotor; along the radial direction of the rotor core, the second short side is located radially outside the second long side, and the second short side is connected to the first short side 2 to form a connection between the first magnetic isolation hole 1 and the first magnetic isolation hole 2. The lengths of the first short side 1 and the first short side 2 are both smaller than the length of the second short side.

[0012] In some embodiments,

[0013] The second magnetic isolation hole 1 includes a relative third short side 1 and a third short side 2, wherein the third short side 1 is relatively close to the first magnetic isolation hole 1, and the third short side 2 extends toward the direction of the permanent magnet slot. The second magnetic isolation hole 2 also includes a relative fourth short side 1 and a fourth short side 2, wherein the fourth short side 2 is connected to the third short side 2 to form a connection between the second magnetic isolation hole 1 and the second magnetic isolation hole 2.

[0014] In some embodiments,

[0015] The first magnetic isolation hole 2 also includes relative straight sides and oblique sides, the straight sides and the first long side 1 are located on the same straight line, the angle between the oblique side and the second short side inside the trapezoidal hole is an obtuse angle, and the obtuse angle is G. The second magnetic isolation hole 1 also includes two relative third long sides, and the second magnetic isolation hole 2 also includes two relative fourth long sides, and the obtuse angle between the third long side and the fourth long side is H, and G and H satisfy the following relationship: 1.5≥G / H≥0.7.

[0016] In some embodiments,

[0017] The first bridge portion of the magnetic isolation bridge is between the first magnetic isolation hole 1 and the second magnetic isolation hole 1. Along the circumferential direction of the rotor core, the width of the first bridge portion is A, the width of the first magnetic isolation hole 1 is F, and A and F satisfy the following relationship: 2.5≥A / F≥1.

[0018] In some embodiments,

[0019] The second bridge portion of the magnetic isolation bridge is between the first magnetic isolation hole 2 and the second magnetic isolation hole 1, and the minimum width of the second bridge portion is B, that is, the minimum distance between the first magnetic isolation hole 2 and the second magnetic isolation hole 1. The first bridge portion of the magnetic isolation bridge is between the first magnetic isolation hole 1 and the second magnetic isolation hole 1. Along the circumferential direction of the rotor core, the width of the first bridge portion is A, and the following relationship is satisfied between B and A: 1.8≥B / A≥0.5.

[0020] In some embodiments,

[0021] The third bridge portion of the magnetic isolation bridge is between the first magnetic isolation hole 2 and the second magnetic isolation hole 2, and the minimum width of the third bridge portion is C, that is, the minimum distance between the first magnetic isolation hole 2 and the second magnetic isolation hole 2. The first bridge portion of the magnetic isolation bridge is between the first magnetic isolation hole 1 and the second magnetic isolation hole 1. Along the circumferential direction of the rotor core, the width of the first bridge portion is A, and the following relationship is satisfied between C and A: 4≥C / A≥2.2.

[0022] In some embodiments,

[0023] The minimum distance between the first magnetic isolation hole and the outer circle of the rotor is D, the minimum distance between the rotor core and the stator is the air gap, the width of the air gap along the radial direction of the rotor core is O, and D and O satisfy the following relationship: 1.6≥D / O≥0.9.

[0024] In some embodiments,

[0025] The second magnetic isolation hole is an arc-shaped hole. Along the radial direction of the rotor core, the arc-shaped hole includes a first arc-shaped edge located on the radial outside and a second arc-shaped edge located on the radial inside, that is, two opposite third long sides. The first arc-shaped edge and the second arc-shaped edge are parallel and both are parallel to the outer circle of the rotor, and the spacing between the first arc-shaped edge and the second arc-shaped edge is the width E. Along the circumferential direction of the rotor core, the width of the first magnetic isolation hole is F, and E and F satisfy the following relationship: 1.4≥E / F≥0.5.

[0026] In some embodiments,

[0027] The minimum distance between the second magnetic isolation hole 2 and the outer circle of the rotor is greater than the minimum distance between the second magnetic isolation hole 1 and the outer circle of the rotor. The minimum distance between the second magnetic isolation hole 2 and the permanent magnet slot is I. The width dimension of the permanent magnet is J. I and J satisfy the following relationship: 2.3≥I / J≥0.7.

[0028] In some embodiments,

[0029] The minimum distance between the second magnetic isolation hole 2 and the outer circle of the rotor is greater than the minimum distance between the second magnetic isolation hole 1 and the outer circle of the rotor. The minimum distance between the second magnetic isolation hole 2 and the permanent magnet slot is 1. The angle between the hypotenuse and the second long side in the inner part of the trapezoidal hole is an acute angle. In the same magnetic pole, the position of the acute angle of the first magnetic isolation hole 2 is the closest to the permanent magnet slot, and the distance is greater than 0 and is also 1.

[0030] The present invention also provides a permanent magnet synchronous motor, which includes the rotor structure of the permanent magnet synchronous motor mentioned above.

[0031] The present invention also provides a compressor, which includes the aforementioned permanent magnet synchronous motor.

[0032] The rotor structure of a permanent magnet synchronous motor, a permanent magnet synchronous motor, and a compressor provided by the present invention have the following beneficial effects:

[0033] The present invention adopts the structure of the first and second magnetic isolation holes opened on the rotor core. The first magnetic isolation hole includes the first magnetic isolation hole 1 and the first magnetic isolation hole 2. The first magnetic isolation hole 1 and the first magnetic isolation hole 2 are both hole structures and are interconnected. The first magnetic isolation hole 1 is relatively close to the outer circle of the rotor, the first magnetic isolation hole 2 is relatively close to the permanent magnet slot, and the minimum width of the first magnetic isolation hole 1 along the circumferential direction of the rotor core is smaller than the minimum width of the first magnetic isolation hole 2; the second magnetic isolation hole is located between at least part of the structure of the first magnetic isolation hole and the outer circle of the rotor; the second magnetic isolation hole includes the second magnetic isolation hole 1 and the second magnetic isolation hole 2. The second magnetic isolation hole one and the second magnetic isolation hole two are both hole structures and are interconnected. The second magnetic isolation hole one is relatively close to the outer circle of the rotor, and the second magnetic isolation hole two is relatively close to the permanent magnet slot, and at least one bent magnetic isolation bridge is formed between the second magnetic isolation hole and the first magnetic isolation hole. Through the above-mentioned specific structures of the first and second magnetic isolation holes, the magnetic flux direction can be improved, the proportion of air gap magnetic density harmonics can be reduced, the motor torque pulsation can be reduced, the electromagnetic force amplitude can be reduced, and especially the 6-fold frequency vibration noise of the motor can be reduced, effectively solving the problems of high air gap magnetic density waveform distortion rate and large harmonic proportion of permanent magnet synchronous motors in the prior art. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 1 is a top view of the permanent magnet synchronous motor of the present invention;

[0035] Figure 2 yes Figure 1 A top view of the rotor structure of the permanent magnet synchronous motor;

[0036] Figure 3 yes Figure 2 The structure of the magnetic isolation hole is enlarged Figure 1 ;

[0037] Figure 4 yes Figure 3 The structure of the magnetic isolation hole is enlarged Figure 2 ;

[0038] Figure 5 yes Figure 3 The structure of the magnetic isolation hole is enlarged Figure 3 ;

[0039] Figure 6 yes Figure 3 The structure of the magnetic isolation hole is enlarged Figure 4 ;

[0040] Figure 7 Schematic diagram of the relationship between A / F and peak electromagnetic force density of the present invention;

[0041] Figure 8 This is a comparison chart of the peak electromagnetic force density of a traditional motor and the new motor of the present invention;

[0042] Figure 9 This is a comparison chart of the compressor noise of the traditional motor and the new motor of the present invention.

[0043] The reference numerals indicate:

[0044] 1. Rotor core; 2. Permanent magnet; 3. Permanent magnet slot; 4. First magnetic isolation hole; 5. Second magnetic isolation hole; 6. First magnetic isolation hole 1; 7. First magnetic isolation hole 2; 8. Second magnetic isolation hole 1; 9. Second magnetic isolation hole 2; 10. Magnetic isolation bridge; 11. First short side 1; 11', first short side 2; 12. First long side 1; 12', first long side 2; 13. Second short side; 14. Second long side; 15. Third short side 1; 15', third short side 2; 16. Fourth short side 1; 16', fourth short side 2; 17. Third long side; 18. Fourth long side; 19. Straight side; 20. Oblique side; 21. First bridge portion; 22. Second bridge portion; 23. Third bridge portion; 24. Stator. DETAILED DESCRIPTION

[0045] The following will be combined with the accompanying drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, rather than all the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is in no way intended to limit the present invention and its application or use. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0046] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, devices, components and / or combinations thereof.

[0047] Unless otherwise specifically stated, the relative arrangement of the parts and steps, the numerical expressions and the numerical values ​​set forth in these embodiments do not limit the scope of the present invention. At the same time, it should be understood that, for ease of description, the sizes of the various parts shown in the drawings are not drawn according to the actual proportional relationship. The techniques, methods and equipment known to those of ordinary skill in the relevant art may not be discussed in detail, but where appropriate, the techniques, methods and equipment should be considered as part of the authorization specification. In all examples shown and discussed here, any specific values ​​should be interpreted as being merely exemplary and not as limiting. Therefore, other examples of the exemplary embodiments may have different values. It should be noted that similar numbers and letters represent similar items in the following figures, and therefore, once an item is defined in one figure, it does not need to be further discussed in subsequent figures.

[0048] In the description of the present invention, it should be understood that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "horizontal, vertical, perpendicular, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the device or element referred to must have a specific direction or be constructed and operated in a specific direction. Therefore, they cannot be understood as limiting the scope of protection of the present invention; the directional words "inside and outside" refer to the inside and outside relative to the outline of each component itself.

[0049] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used herein to describe the spatial positional relationship of a device or feature to other devices or features as shown in the figures. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figures. For example, if the device in the drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" can include both "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0050] In addition, it should be noted that the use of terms such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of the present invention.

[0051] like Figure 1-9 As shown, the present invention provides a rotor structure of a permanent magnet synchronous motor, which includes:

[0052] A rotor core 1 and a permanent magnet 2. The rotor core 1 has a permanent magnet slot 3 for accommodating the permanent magnet 2. In the same magnetic pole, the rotor core 1 is provided with a first magnetic isolation hole 4 and a second magnetic isolation hole 5. The first magnetic isolation hole 4 and the second magnetic isolation hole 5 are both located between the permanent magnet slot 3 and the rotor outer circle of the rotor core 1.

[0053] The first magnetic isolation hole 4 includes a first magnetic isolation hole 1 6 and a first magnetic isolation hole 2 7. The first magnetic isolation hole 1 6 and the first magnetic isolation hole 2 7 are both hole structures and are interconnected. The first magnetic isolation hole 1 6 is relatively close to the outer circle of the rotor, and the first magnetic isolation hole 2 7 is relatively close to the permanent magnet slot 3. In addition, the minimum width of the first magnetic isolation hole 1 6 along the circumferential direction of the rotor core is smaller than the minimum width of the first magnetic isolation hole 2 7.

[0054] The second magnetic isolation hole 5 is located between at least part of the structure of the first magnetic isolation hole 4 and the outer circle of the rotor; the second magnetic isolation hole 5 includes a second magnetic isolation hole 8 and a second magnetic isolation hole 9, the second magnetic isolation hole 8 and the second magnetic isolation hole 2 9 are both hole structures and are interconnected, the second magnetic isolation hole 8 is relatively close to the outer circle of the rotor, the second magnetic isolation hole 2 9 is relatively close to the permanent magnet slot 3, and at least a bent magnetic isolation bridge 10 is formed between the second magnetic isolation hole 5 and the first magnetic isolation hole 4.

[0055] That is, the outer side of the first magnetic isolation hole of the present invention is close to the outer circle of the rotor, and the inner side is close to the permanent magnet. The outer width F of the first magnetic isolation hole radially inward is narrow, and the inner width of the first magnetic isolation hole is large. The second magnetic isolation hole is located between the first magnetic isolation hole and the outer circle of the rotor.

[0056] A second magnetic isolation hole is opened on the magnetic pole of the iron core. The second magnetic isolation hole is in a broken line shape. The outer side of the second magnetic isolation hole is close to the outer circle of the rotor, and the inner side is close to the permanent magnet. The outer hole portion of the second magnetic isolation hole extends toward the outer strip-shaped hole portion of the first magnetic isolation hole, and the inner hole portion of the second magnetic isolation hole is close to the inner trapezoidal hole portion of the first magnetic isolation hole. The second magnetic isolation hole and the first magnetic isolation hole form a multi-section bent magnetic isolation bridge.

[0057] The present invention adopts the structure of the first and second magnetic isolation holes opened on the rotor core. The first magnetic isolation hole includes the first magnetic isolation hole 1 and the first magnetic isolation hole 2. The first magnetic isolation hole 1 and the first magnetic isolation hole 2 are both hole structures and are interconnected. The first magnetic isolation hole 1 is relatively close to the outer circle of the rotor, the first magnetic isolation hole 2 is relatively close to the permanent magnet slot, and the minimum width of the first magnetic isolation hole 1 along the circumferential direction of the rotor core is smaller than the minimum width of the first magnetic isolation hole 2; the second magnetic isolation hole is located between at least part of the structure of the first magnetic isolation hole and the outer circle of the rotor; the second magnetic isolation hole includes the second magnetic isolation hole 1 and the second magnetic isolation hole 2. The second magnetic isolation hole one and the second magnetic isolation hole two are both hole structures and are interconnected. The second magnetic isolation hole one is relatively close to the outer circle of the rotor, and the second magnetic isolation hole two is relatively close to the permanent magnet slot, and at least one bent magnetic isolation bridge is formed between the second magnetic isolation hole and the first magnetic isolation hole. Through the above-mentioned specific structures of the first and second magnetic isolation holes, the magnetic flux direction can be improved, the proportion of air gap magnetic density harmonics can be reduced, the motor torque pulsation can be reduced, the electromagnetic force amplitude can be reduced, and especially the 6-fold frequency vibration noise of the motor can be reduced, effectively solving the problems of high air gap magnetic density waveform distortion rate and large harmonic proportion of permanent magnet synchronous motors in the prior art.

[0058] The present invention provides a permanent magnet synchronous motor rotor structure, comprising a rotor core and permanent magnets. The rotor core is provided with permanent magnet slots for accommodating permanent magnets, the permanent magnets on the rotor forming alternating N-S poles. A first magnetic isolation hole is provided on the magnetic pole of the core, the outer side of the first magnetic isolation hole being close to the outer circumference of the rotor and the inner side being close to the permanent magnets. The outer side of the first magnetic isolation hole is narrow, while the inner side is wide. The outer hole portion of the first magnetic isolation hole is strip-shaped, while the inner hole portion of the first magnetic isolation hole is trapezoidal. The two hole portions together constitute the first magnetic isolation hole. A second magnetic isolation hole is provided on the magnetic pole of the core, the second magnetic isolation hole being in a broken line shape. The outer side of the second magnetic isolation hole is close to the outer circumference of the rotor and the inner side is close to the permanent magnets. The outer hole portion of the second magnetic isolation hole extends toward the outer bar-shaped hole portion of the first magnetic isolation hole, and the inner hole portion of the second magnetic isolation hole is close to the inner trapezoidal hole portion of the first magnetic isolation hole. The second magnetic isolation hole and the first magnetic isolation hole form a multi-section curved magnetic isolation bridge. Permanent magnet motors rely on permanent magnets to generate their main magnetic field. These motors have high air gap flux density, high efficiency, compact size, high power density, simple structure, and high reliability, making them widely used in various industries. However, the permanent magnet materials used in permanent magnet synchronous motors, with fixed grades and materials, maintain a constant magnetic energy product, making air gap magnetic field adjustment difficult. Furthermore, the motor's slot structure results in high harmonic content in the air gap flux density and back EMF, resulting in a high peak electromagnetic force, which in turn leads to high torque pulsation and vibration noise. The present invention, by providing first and second magnetic isolation holes with novel structures on the rotor, can alter the magnetic resistance distribution throughout the motor's magnetic circuit, improve the magnetic flux distribution, reduce the air gap flux density harmonics, lower the peak electromagnetic force, and reduce the electromagnetic vibration noise.

[0059] In some embodiments,

[0060] In the plane where the axial end face of the rotor core 1 is located, the first magnetic isolation hole 6 is a rectangular hole, and the first magnetic isolation hole 7 is a trapezoidal hole. The rectangular hole includes a parallel first short side 11 and a first short side 11', and the rectangular hole also includes a parallel first long side 12 and a first long side 12'. The trapezoidal hole includes a parallel second short side 13 and a second long side 14. Along the radial direction of the rotor core 1, the first short side 11 of the rectangular hole is located radially outside the first short side 11' and opposite to the outer circle of the rotor; along the radial direction of the rotor core 1, the second short side 13 is located radially outside the second long side 14, and the second short side 13 is connected to the first short side 11' to form a connection between the first magnetic isolation hole 6 and the first magnetic isolation hole 7. The lengths of the first short side 11 and the first short side 11' are both less than the length of the second short side 13.

[0061] This is a further preferred structural form of the first magnetic isolation hole 1 and the first magnetic isolation hole 2 of the first magnetic isolation hole of the present invention, which defines the first magnetic isolation hole 1 as a rectangular hole located on the radial outside, and the first magnetic isolation hole 2 as a trapezoidal hole located on the radial inside, forming a connectivity relationship between the rectangular hole and the trapezoidal hole, thereby further changing the magnetic resistance distribution of the motor magnetic circuit at this position, which can improve the direction of the magnetic flux of the magnetic circuit, reduce the air gap magnetic density harmonics of the motor, reduce the electromagnetic force peak of the motor, and reduce the electromagnetic vibration noise of the motor.

[0062] In some embodiments,

[0063] The second magnetic isolation hole 8 includes two opposite third short sides 15 and 15', the third short side 15 is relatively close to the first magnetic isolation hole 6, and the third short side 15' extends toward the direction of the permanent magnet slot 3. The second magnetic isolation hole 9 also includes an opposite fourth short side 16 and 16', the fourth short side 16' is connected to the third short side 15' to form a connection between the second magnetic isolation hole 8 and the second magnetic isolation hole 2 9.

[0064] This is a further preferred structural form of the second magnetic isolation hole one and the second magnetic isolation hole two of the second magnetic isolation hole of the present invention, which defines the second magnetic isolation hole one as a strip hole located on the radial outside, and the first magnetic isolation hole two as a strip hole located on the radial inside, forming a connectivity relationship between the two strip holes, thereby further changing the magnetic resistance distribution of the motor magnetic circuit at the position of the second magnetic isolation hole, which can improve the direction of the magnetic flux of the magnetic circuit, reduce the air gap magnetic density harmonics of the motor, reduce the electromagnetic force peak of the motor, and reduce the electromagnetic vibration noise of the motor.

[0065] In some embodiments,

[0066] The first magnetic isolation hole 2 7 also includes a relative straight side 19 and a beveled side 20, and the straight side 19 is located on the same straight line as the first long side 12. The angle between the beveled side 20 and the second short side 13 inside the trapezoidal hole is an obtuse angle, and the obtuse angle is G. The second magnetic isolation hole 1 8 also includes two relative third long sides 17, and the second magnetic isolation hole 2 9 also includes two relative fourth long sides 18, and the obtuse angle between the third long side 17 and the fourth long side 18 is H. At the same time, G and H satisfy the following relationship: 1.5≥G / H≥0.7.

[0067] The present invention preferably sets the angle between the outer side of the trapezoidal hole portion on the inner side of the first magnetic isolation hole close to the second hole portion and the hypotenuse to an obtuse angle. The second magnetic isolation hole is in a broken line shape, and the two hole portions of the second magnetic isolation hole also form an obtuse angle. The two obtuse angles are adjacent, the obtuse angle of the trapezoidal hole is G, and the obtuse angle of the second magnetic isolation hole is H. G and H satisfy the relationship: 1.5≥G / H≥0.7. Setting the above relationship within this range can make the trapezoidal magnetic isolation hole and the bent magnetic isolation hole arranged adjacent to each other, so that there are more magnetic lines of force between the two holes, and fewer magnetic lines of force passing through the two magnetic isolation holes, so that the magnetic permeability in the radial direction of the rotor is more uniform, thereby further improving the air gap magnetic field distribution of the motor, reducing the proportion of air gap magnetic density harmonics, reducing the electromagnetic force peak, and reducing the vibration noise of the motor.

[0068] In some embodiments,

[0069] The first bridge portion 21 of the magnetic isolation bridge 10 is located between the first magnetic isolation hole 6 and the second magnetic isolation hole 8. Along the circumferential direction of the rotor core 1, the width of the first bridge portion 21 is A, and the width of the first magnetic isolation hole 6 is F, and A and F satisfy the following relationship: 2.5≥A / F≥1.

[0070] The present invention is further preferred that a bridge portion is left between the outer strip hole portion of the first magnetic isolation hole and the outer hole portion of the second magnetic isolation hole, that is, the first bridge portion of the multi-section bent magnetic isolation bridge, the first bridge portion is along the radial direction of the rotor, the width of the magnetic isolation bridge is A, the width of the outer hole portion of the first magnetic isolation hole is F, A and F satisfy the relationship: 2.5≥A / F≥1, and setting the above relationship within this range can better control the number of magnetic lines passing through the bridge, and combine with the slotted stator to reduce the tooth slot effect, thereby reducing the proportion of air gap magnetic density harmonics and reducing the 6th frequency electromagnetic force peak.

[0071] The present invention discloses a novel permanent magnet synchronous motor rotor structure. Due to the adoption of a novel magnetic isolation hole, a first magnetic isolation hole is provided on the magnetic pole of the iron core. The outer width of the first magnetic isolation hole is narrow, and the inner width of the first magnetic isolation hole is large. The outer hole portion is strip-shaped, and the inner hole portion is trapezoidal. A second magnetic isolation hole is provided on the magnetic pole of the iron core. The second magnetic isolation hole is in a broken line shape. The two magnetic isolation holes are adjacent to each other. The second magnetic isolation hole and the first magnetic isolation hole form a multi-section bent magnetic isolation bridge. The width of the magnetic isolation bridge is A, and the width of the outer hole portion of the first magnetic isolation hole is F. A and F satisfy the relationship: 2.5≥A / F≥1, so that the magnetic isolation hole can effectively improve the direction of the magnetic flux, thereby reducing the proportion of air gap magnetic density harmonics, reducing the motor torque pulsation, reducing the electromagnetic force amplitude, and reducing the 6-fold frequency vibration noise of the motor.

[0072] In some embodiments,

[0073] The second bridge portion 22 of the magnetic isolation bridge 10 is located between the first magnetic isolation hole 27 and the second magnetic isolation hole 18. The minimum width of the second bridge portion 22 is B, that is, the minimum distance between the first magnetic isolation hole 27 and the second magnetic isolation hole 18 (subject to text). The first bridge portion 21 of the magnetic isolation bridge 10 is located between the first magnetic isolation hole 16 and the second magnetic isolation hole 18. Along the circumferential direction of the rotor core 1, the width of the first bridge portion 21 is A, and the following relationship is satisfied between B and A: 1.8≥B / A≥0.5.

[0074] The present invention is further preferred in that a bridge portion is left between the outer hole portion of the second magnetic isolation hole and the inner trapezoidal hole portion of the first magnetic isolation hole, that is, the second bridge portion of the multi-section bent magnetic isolation bridge. The minimum width of the magnetic isolation bridge is B, and B and A satisfy the relationship: 1.8≥B / A≥0.5, which can further control the magnetic resistance at different positions in the middle of the magnetic pole, further balance the magnetic permeability distribution at various locations on the magnetic pole, reduce torque pulsation, reduce motor vibration noise, and enhance customer experience.

[0075] In some embodiments,

[0076] Between the first magnetic isolation hole 27 and the second magnetic isolation hole 29 is the third bridge portion 23 of the magnetic isolation bridge 10. The minimum width of the third bridge portion 23 is C, that is, the minimum distance between the first magnetic isolation hole 27 and the second magnetic isolation hole 29. Between the first magnetic isolation hole 16 and the second magnetic isolation hole 18 is the first bridge portion 21 of the magnetic isolation bridge 10. Along the circumferential direction of the rotor core 1, the width of the first bridge portion 21 is A, and the following relationship is satisfied between C and A: 4≥C / A≥2.2.

[0077] The present invention is further preferred that a bridge portion is left between the inner hole portion of the second magnetic isolation hole and the inner trapezoidal hole portion of the first magnetic isolation hole, that is, the third bridge portion of the multi-section bent magnetic isolation bridge, the minimum width of the magnetic isolation bridge is C, C and A satisfy the relationship: 4≥C / A≥2.2, which can make the third magnetic isolation bridge close to the permanent magnet, control the direction of the magnetic flux starting from the magnetic flux source, further reduce the radial magnetic density harmonics, reduce the 18-fold frequency electromagnetic force peak, and reduce the noise generated by the electromagnetic force.

[0078] In some embodiments,

[0079] The minimum distance between the first magnetic isolation hole 6 and the outer circle of the rotor is D, the minimum distance between the rotor core and the stator is the air gap, and the width of the air gap along the radial direction of the rotor core 1 is O. D and O satisfy the following relationship: 1.6≥D / O≥0.9.

[0080] The present invention is further preferred that the outer strip hole portion of the first magnetic isolation hole is close to the outer circle of the rotor, and there is a distance between the outer circle of the rotor. The minimum width of the distance is D, and the width of the air gap is O. D and O satisfy the relationship: 1.6≥D / O≥0.9, which can allow the iron core left between the magnetic isolation hole and the outer circle to allow magnetic lines of force to pass through. The wider the magnetic bridge, the more magnetic lines of force pass through. Within this range, the magnetic lines of force transmitted from the permanent magnet to the stator side can be better guided, thereby improving the air gap magnetic field distribution of the motor, improving the air gap magnetic density waveform, reducing the electromagnetic force peak, and reducing the noise peak of the rotor pole number multiple frequency on the noise spectrum.

[0081] In some embodiments,

[0082] The second magnetic isolation hole 8 is an arc-shaped hole structure. Along the radial direction of the rotor core 1, the arc-shaped hole includes a first arc-shaped edge located on the radial outside and a second arc-shaped edge located on the radial inside, that is, two opposite third long sides 17. The first arc-shaped edge and the second arc-shaped edge are parallel and parallel to the outer circle of the rotor (that is, the first arc-shaped edge, the second arc-shaped edge and the outer circle of the rotor are all concentric arcs with the same center), and the spacing between the first arc-shaped edge and the second arc-shaped edge is the width E. Along the circumferential direction of the rotor core 1, the width of the first magnetic isolation hole 6 is F, and E and F satisfy the following relationship: 1.4≥E / F≥0.5.

[0083] The present invention is further preferred that the outer hole portion of the second magnetic isolation hole is close to the outer circle of the rotor, and the outer hole portion of the second magnetic isolation hole is an arc-shaped hole structure parallel to the outer circle of the rotor. The arc-shaped hole portion has a certain width, which is E. The width of the outer hole portion of the first magnetic isolation hole is F. E and F satisfy the relationship: 1.4≥E / F≥0.5, which can enable the magnetic isolation hole to extend circumferentially along the outer circumference of the rotor, increase the magnetic resistance here, the magnetic resistance of the first magnetic isolation bridge is small, and the magnetic resistance of the outer hole portion of the first magnetic isolation hole is large. Within this range, the magnetic resistance distribution of the magnetic circuit outside the rotor can be made more uniform, reducing the air gap magnetic density harmonics, reducing the 6th frequency electromagnetic force peak, and reducing the 6th frequency noise.

[0084] In some embodiments,

[0085] The minimum distance between the second magnetic isolation hole 2 9 and the outer circle of the rotor is greater than the minimum distance between the second magnetic isolation hole 1 8 and the outer circle of the rotor. The minimum distance between the second magnetic isolation hole 2 9 and the permanent magnet slot 3 is I. The width dimension of the permanent magnet 2 is J. I and J satisfy the following relationship: 2.3≥I / J≥0.7.

[0086] The present invention is further preferred that the second magnetic isolation hole is in a broken line shape, the distance between the second hole portion and the outer circle is greater than the distance between the first hole portion and the outer circle (minimum distance), the inner hole portion of the second magnetic isolation hole is close to the permanent magnet, the inner hole portion is strip-shaped, and there is a distance between the inner hole portion and the permanent magnet, which is I, the thickness of the permanent magnet is J, and I and J satisfy the relationship: 2.3≥I / J≥0.7, which can further adjust the magnetic flux transmitted by the permanent magnet to the middle and both sides of the magnetic pole, thereby improving the air gap magnetic field distribution of the motor, reducing the proportion of air gap magnetic density harmonics, reducing torque fluctuations, and reducing the vibration noise of the motor.

[0087] In some embodiments,

[0088] The minimum distance between the second magnetic isolation hole 29 and the outer circle of the rotor is greater than the minimum distance between the second magnetic isolation hole 18 and the outer circle of the rotor. The minimum distance between the second magnetic isolation hole 29 and the permanent magnet slot 3 is 1. The angle between the hypotenuse 20 and the second long side 14 in the inner part of the trapezoidal hole is an acute angle. In the same magnetic pole, the position of the acute angle of the first magnetic isolation hole 27 is the closest to the permanent magnet slot 3, and the distance is greater than 0 and is also 1.

[0089] The present invention is further preferred that the inner trapezoidal hole portion of the first magnetic isolation hole is close to the permanent magnet, and the angle between the inner side edge of the inner trapezoidal hole portion of the first magnetic isolation hole close to the permanent magnet and the hypotenuse is an acute angle, and the acute angle is close to the permanent magnet, so that a distance is left between the trapezoidal hole and the permanent magnet, and this distance is equal to the distance I between the inner hole portion of the second magnetic isolation hole and the permanent magnet, which can adjust the magnetic permeability distribution at various locations of the rotor poles, reduce the proportion of air gap magnetic density harmonics, reduce the 6th frequency electromagnetic force peak, and reduce the vibration noise of the motor.

[0090] The present invention also provides a permanent magnet synchronous motor, which includes the rotor structure of the permanent magnet synchronous motor mentioned above.

[0091] The present invention provides a permanent magnet synchronous motor, comprising a rotor core and permanent magnets. The rotor core is provided with permanent magnet slots for accommodating permanent magnets, the permanent magnets on the rotor forming alternating N-S poles, a first magnetic isolation hole is provided on the magnetic pole of the core, the outer side of the first magnetic isolation hole being close to the outer circumference of the rotor and the inner side being close to the permanent magnets, the outer side of the first magnetic isolation hole being narrow and the inner side being wide, the outer hole portion of the first magnetic isolation hole being strip-shaped and the inner hole portion of the first magnetic isolation hole being trapezoidal, the two hole portions together forming the first magnetic isolation hole, a second magnetic isolation hole is provided on the magnetic pole of the core, the second magnetic isolation hole being in a broken line shape, the outer side of the second magnetic isolation hole being close to the outer circumference of the rotor and the inner side being close to the permanent magnets, the outer hole portion of the second magnetic isolation hole extending toward the outer bar-shaped hole portion of the first magnetic isolation hole, the inner hole portion of the second magnetic isolation hole being close to the inner trapezoidal hole portion of the first magnetic isolation hole, and the second magnetic isolation hole and the first magnetic isolation hole forming a multi-section curved magnetic isolation bridge. Permanent magnet motors rely on permanent magnets to generate their main magnetic field. These motors have high air gap flux density, high efficiency, compact size, high power density, simple structure, and high reliability, making them widely used in various industries. However, the permanent magnet materials used in permanent magnet synchronous motors, with fixed grades and materials, maintain a constant magnetic energy product, making air gap magnetic field adjustment difficult. Furthermore, the motor's slot structure results in high harmonic content in the air gap flux density and back EMF, resulting in a high peak electromagnetic force, which in turn leads to high torque pulsation and vibration noise. The present invention, by providing first and second magnetic isolation holes with novel structures on the rotor, can alter the magnetic resistance distribution throughout the motor's magnetic circuit, improve the magnetic flux distribution, reduce the air gap flux density harmonics, lower the peak electromagnetic force, and reduce the electromagnetic vibration noise.

[0092] The present invention also provides a compressor, which includes the aforementioned permanent magnet synchronous motor.

[0093] The present invention can solve the following technical problems:

[0094] 1. Solved the problems of high air gap magnetic flux waveform distortion rate and large harmonic proportion of permanent magnet synchronous motor.

[0095] 2. Solve the problem of large 6-fold frequency electromagnetic force of the motor.

[0096] 3. Solve the problem of large electromagnetic force of 18 times the frequency of the motor. (The same motor can have 6 times, 18 times the electromagnetic force, etc.).

[0097] 4. Solve the problem of large motor vibration and noise.

[0098] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention. The above description is merely a preferred embodiment of the present invention. It should be noted that those skilled in the art can make various improvements and variations without departing from the technical principles of the present invention, and such improvements and variations shall also be considered within the scope of protection of the present invention.

Claims

1. A rotor structure of a permanent magnet synchronous motor, characterized in that: include: A rotor core (1) and a permanent magnet (2), wherein the rotor core (1) is provided with a permanent magnet slot (3) for accommodating the permanent magnet (2), and in the same magnetic pole, the rotor core (1) is provided with a first magnetic isolation hole (4) and a second magnetic isolation hole (5), wherein the first magnetic isolation hole (4) and the second magnetic isolation hole (5) are both located between the permanent magnet slot (3) and the rotor outer circle of the rotor core (1); The first magnetic isolation hole (6) and the first magnetic isolation hole (7) are both hole structures and are interconnected. The first magnetic isolation hole (6) and the first magnetic isolation hole (4) include the first magnetic isolation hole (6) and the first magnetic isolation hole (7). The first magnetic isolation hole (6) is close to the outer circle of the rotor, and the first magnetic isolation hole (7) is relatively close to the permanent magnet slot (3). In addition, the minimum width of the first magnetic isolation hole (6) along the circumferential direction of the rotor core is smaller than the minimum width of the first magnetic isolation hole (7). The second magnetic isolation hole (5) is located between at least a part of the structure of the first magnetic isolation hole (4) and the outer circle of the rotor; the second magnetic isolation hole (5) includes a second magnetic isolation hole (8) and a second magnetic isolation hole (9), the second magnetic isolation hole (8) and the second magnetic isolation hole (9) are both hole structures and are interconnected, the second magnetic isolation hole (8) is relatively close to the outer circle of the rotor, the second magnetic isolation hole (9) is relatively close to the permanent magnet slot (3), and at least one bent magnetic isolation bridge (10) is formed between the second magnetic isolation hole (5) and the first magnetic isolation hole (4).

2. The rotor structure of the permanent magnet synchronous motor according to claim 1, characterized in that: In the plane where the axial end face of the rotor core (1) is located, the first magnetic isolation hole (6) is a rectangular hole, the first magnetic isolation hole (7) is a trapezoidal hole, the rectangular hole includes a first short side (11) and a first short side (11') in parallel, the rectangular hole also includes a first long side (12) and a first long side (12') in parallel, the trapezoidal hole includes a second short side (13) and a second long side (14) in parallel, along the radial direction of the rotor core (1), the first short side (11) of the rectangular hole is parallel to the first short side (11) of the rotor core (1). ) is located radially outside the first short side 2 (11') and opposite to the outer circle of the rotor; along the radial direction of the rotor core (1), the second short side (13) is located radially outside the second long side (14), and the second short side (13) is connected to the first short side 2 (11') to form a connection between the first magnetic isolation hole 1 (6) and the first magnetic isolation hole 2 (7), and the lengths of the first short side 1 (11) and the first short side 2 (11') are both smaller than the length of the second short side (13).

3. The rotor structure of the permanent magnet synchronous motor according to claim 2, characterized in that: The second magnetic isolation hole 1 (8) includes a relative third short side 1 (15) and a third short side 2 (15'), the third short side 1 (15) is relatively close to the first magnetic isolation hole 1 (6), and the third short side 2 (15') extends toward the permanent magnet slot (3). The second magnetic isolation hole 2 (9) also includes a relative fourth short side 1 (16) and a fourth short side 2 (16'), the fourth short side 2 (16') is connected to the third short side 2 (15') to form a connection between the second magnetic isolation hole 1 (8) and the second magnetic isolation hole 2 (9).

4. The rotor structure of the permanent magnet synchronous motor according to claim 3, characterized in that: The first magnetic isolation hole 2 (7) also includes a relative straight side (19) and a bevel side (20), the straight side (19) and the first long side 1 (12) are located on the same straight line, and the angle between the bevel side (20) and the second short side (13) inside the trapezoidal hole is an obtuse angle, and the obtuse angle is G. The second magnetic isolation hole 1 (8) also includes two relative third long sides (17), and the second magnetic isolation hole 2 (9) also includes two relative fourth long sides (18), and the obtuse angle between the third long side (17) and the fourth long side (18) is H, and G and H satisfy the following relationship: 1.5≥G / H≥0.

7.

5. The rotor structure of the permanent magnet synchronous motor according to claim 1, characterized in that: Between the first magnetic isolation hole (6) and the second magnetic isolation hole (8) is the first bridge portion (21) of the magnetic isolation bridge (10), and along the circumferential direction of the rotor core (1), the width of the first bridge portion (21) is A, the width of the first magnetic isolation hole (6) is F, and A and F satisfy the following relationship: 2.5≥A / F≥1.

6. The rotor structure of the permanent magnet synchronous motor according to claim 1, characterized in that: The second bridge portion (22) of the magnetic isolation bridge (10) is located between the first magnetic isolation hole 2 (7) and the second magnetic isolation hole 1 (8), and the minimum width of the second bridge portion (22) is B, that is, the minimum distance between the first magnetic isolation hole 2 (7) and the second magnetic isolation hole 1 (8). The first bridge portion (21) of the magnetic isolation bridge (10) is located between the first magnetic isolation hole 1 (6) and the second magnetic isolation hole 1 (8). Along the circumferential direction of the rotor core (1), the width of the first bridge portion (21) is A, and the following relationship is satisfied between B and A: 1.8≥B / A≥0.

5.

7. The rotor structure of the permanent magnet synchronous motor according to claim 1, characterized in that: The third bridge portion (23) of the magnetic isolation bridge (10) is located between the first magnetic isolation hole 2 (7) and the second magnetic isolation hole 2 (9), and the minimum width of the third bridge portion (23) is C, that is, the minimum distance between the first magnetic isolation hole 2 (7) and the second magnetic isolation hole 2 (9). The first bridge portion (21) of the magnetic isolation bridge (10) is located between the first magnetic isolation hole 1 (6) and the second magnetic isolation hole 1 (8). Along the circumferential direction of the rotor core (1), the width of the first bridge portion (21) is A, and the following relationship is satisfied between C and A: 4≥C / A≥2.

2.

8. The rotor structure of the permanent magnet synchronous motor according to claim 1, characterized in that: The minimum distance between the first magnetic isolation hole (6) and the outer circle of the rotor is D, the minimum distance between the rotor core and the stator is an air gap, the width of the air gap along the radial direction of the rotor core (1) is O, and D and O satisfy the following relationship: 1.6≥D / O≥0.

9.

9. The rotor structure of the permanent magnet synchronous motor according to claim 1, characterized in that: The second magnetic isolation hole (8) is an arc-shaped hole. Along the radial direction of the rotor core (1), the arc-shaped hole includes a first arc-shaped side located on the radial outer side and a second arc-shaped side located on the radial inner side, that is, two opposite third long sides (17). The first arc-shaped side and the second arc-shaped side are parallel and parallel to the outer circle of the rotor, and the spacing between the first arc-shaped side and the second arc-shaped side is a width E. Along the circumferential direction of the rotor core (1), the width of the first magnetic isolation hole (6) is F, and E and F satisfy the following relationship: 1.4≥E / F≥0.

5.

10. The rotor structure of the permanent magnet synchronous motor according to claim 1, characterized in that: The minimum distance between the second magnetic isolation hole 2 (9) and the outer circle of the rotor is greater than the minimum distance between the second magnetic isolation hole 1 (8) and the outer circle of the rotor, the minimum distance between the second magnetic isolation hole 2 (9) and the permanent magnet slot (3) is I, the width dimension of the permanent magnet (2) is J, and I and J satisfy the following relationship: 2.3≥I / J≥0.

7.

11. The rotor structure of the permanent magnet synchronous motor according to claim 4, characterized in that: The minimum distance between the second magnetic isolation hole 2 (9) and the outer circle of the rotor is greater than the minimum distance between the second magnetic isolation hole 1 (8) and the outer circle of the rotor. The minimum distance between the second magnetic isolation hole 2 (9) and the permanent magnet slot (3) is 1. The angle between the hypotenuse (20) and the second long side (14) in the inner part of the trapezoidal hole is an acute angle. In the same magnetic pole, the position of the acute angle of the first magnetic isolation hole 2 (7) is the closest to the permanent magnet slot (3), and the distance is greater than 0 and is also 1.

12. A permanent magnet synchronous motor, characterized in that: A rotor structure comprising a permanent magnet synchronous motor according to any one of claims 1 to 11.

13. A compressor, characterized in that: Including the permanent magnet synchronous motor as described in claim 12.

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