Rotor, motor and compressor

Abstract

The utility model discloses a rotor, motor and compressor relates to motor technical field, the rotor includes rotor iron core and permanent magnet, rotor iron core includes iron core body, at least one end portion of iron core body is equipped with at least one second punching sheet, iron core body includes a plurality of first punching sheets that are laminated along the axial direction, and the first punching sheets are laminated along the axial direction. The first punching sheet is provided with a magnetic steel groove, the length of the magnetic steel groove is d1, the second punching sheet is provided with a magnetic isolation groove corresponding to the magnetic steel groove, the length of the magnetic isolation groove is d2, the width of the magnetic steel groove is W1, the width of the magnetic isolation groove is W2, W1 is less than W2, d1 is less than or equal to d2, and the permanent magnet is arranged in the magnetic steel groove. According to the technical scheme provided by the utility model, the rotational inertia of the rotor iron core can be increased, and the magnetic leakage condition of the rotor iron core can be reduced.

Description

Technical Field

[0001] This utility model relates to the field of motor technology, and in particular to a rotor, motor and compressor. Background Technology

[0002] Currently, in order to increase the magnetic flux of the stator core, permanent magnet motors in existing technology generally lengthen the stator teeth. However, this leads to a smaller rotor outer diameter, resulting in a smaller rotor moment of inertia. Consequently, the rotor may be more prone to speed fluctuations or slight vibrations during operation, affecting the overall stable operation of the equipment. Moreover, the rotor lamination structure design and magnetic flux distribution in existing permanent magnet motors are unreasonable, resulting in a large amount of magnetic leakage and low motor efficiency. Utility Model Content

[0003] The main objective of this invention is to propose a rotor, motor, and compressor that aims to increase the rotor's moment of inertia while reducing the leakage flux of the rotor core.

[0004] To achieve the above objectives, the rotor proposed in this utility model comprises:

[0005] A rotor core includes a core body, at least one end of the core body having at least one second lamination. The core body includes a plurality of first laminations stacked axially. Each first lamination has a magnetic slot with a length of d1. The second laminations have corresponding magnetic slots with a magnetic isolation slot with a length of d2. The width of the magnetic slot is W1, and the width of the magnetic isolation slot is W2, satisfying: W1 < W2, d1 ≤ d2, and...

[0006] A permanent magnet is disposed within the magnetic steel groove.

[0007] In one embodiment, at least one second lamination is provided at both ends of the core body.

[0008] In one embodiment, at least a portion of the magnet slot of the first lamination is provided with a first limiting protrusion, which is used to press against the permanent magnet.

[0009] In one embodiment, the thickness of the permanent magnet is T, the first limiting protrusion extends along the width direction of the magnet groove, and the maximum straight-line distance of the extension is L1, satisfying: 0 < W1 - L1 < T.

[0010] In one embodiment, at least a portion of the magnetic isolation groove of the second lamination has a limiting portion on its groove wall, the limiting portion being used to limit the end of the permanent magnet.

[0011] In one embodiment, the limiting portion is configured as a second limiting protrusion; or

[0012] The limiting part is configured as a limiting rib, and the limiting rib connects the two groove walls of the magnetic isolation groove arranged along the width direction.

[0013] In one embodiment, the rotor core is provided with rivet holes, the distance from the rivet holes to the magnet slots is X1, and X1 satisfies: X1 > 0.5 mm; the distance from the rivet holes to the magnetic isolation slots is X2, and X2 satisfies: X2 > 0.5 mm.

[0014] In one embodiment, the magnetic steel groove and the magnetic isolation groove are in the shape of a straight line, a V-shape, or a U-shape.

[0015] This utility model also proposes an electric motor, including a stator and the aforementioned rotor, wherein the rotor is rotatably disposed within the stator.

[0016] In one embodiment, the maximum outer diameter of the stator is D0, and the maximum outer diameter of the rotor is D1, satisfying: 0.48 < D1 / D0 < 0.58.

[0017] This utility model also proposes a compressor, including the aforementioned motor.

[0018] The technical solution of this utility model increases the weight of the rotor core by setting at least one second lamination at at least one end of the iron core body equipped with permanent magnets, thereby increasing the rotor's moment of inertia. Secondly, the width W2 of the magnetic isolation slot of the second lamination is greater than the width W1 of the magnet slot, thus increasing the obstruction distance of the magnetic flux path at the rotor end and reducing axial magnetic leakage, allowing more magnetic flux to enter the stator core of the motor. Furthermore, the length d1 of the magnet slot is less than or equal to the length d2 of the magnetic isolation slot, and the width W1 of the magnet slot is less than the width W2 of the magnetic isolation slot. This indicates that the area of ​​the magnet slot of the first lamination is smaller than the area of ​​the magnetic isolation slot of the second lamination; this increases the axial magnetic isolation effect of the second lamination. The larger the area of ​​the magnetic isolation slot, the stronger the air obstruction path for the magnetic lines of force, thereby reducing axial magnetic flux leakage. Therefore, this technical solution can increase the rotor's moment of inertia while reducing rotor core magnetic leakage. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of this utility model 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 this utility model. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0020] Figure 1A schematic diagram of the structure of a rotor core according to an embodiment of the rotor provided by this utility model;

[0021] Figure 2 for Figure 1 A magnified view of a section at point A in the middle;

[0022] Figure 3 A cross-sectional structural schematic diagram of the first embodiment of the rotor core provided by this utility model;

[0023] Figure 4 A cross-sectional structural schematic diagram of the second embodiment of the rotor core provided by this utility model;

[0024] Figure 5 A schematic diagram of the axial leakage magnetic path at the first lamination of the rotor core of the rotor provided by this utility model.

[0025] Figure 6 A schematic diagram of the axial leakage magnetic path at the second lamination of the rotor core provided by this utility model;

[0026] Figure 7 A schematic diagram of the structure of the first lamination of the rotor without the first limiting protrusion provided by this utility model;

[0027] Figure 8 A schematic diagram of the structure of the first lamination with a first limiting protrusion on the rotor provided by this utility model;

[0028] Figure 9 A schematic diagram of the structure of the second lamination of the rotor having a limiting part provided by this utility model;

[0029] Figure 10 A comparison diagram of the COP of the compressor using the rotor provided by this utility model and the COP of the compressor using conventional technology.

[0030] Explanation of icon numbers:

[0031] 10. Rotor; 100. Rotor core; 110. Core body; 111. First lamination; 112. Magnet slot; 113. First limiting protrusion; 120. Second lamination; 121. Magnetic isolation slot; 122. Limiting part; 130. Rivet hole.

[0032] The purpose, features, and advantages of this utility model will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0033] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present utility model.

[0034] It should be noted that if the embodiments of this utility model 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 specific posture. If the specific posture changes, the directional indicators will also change accordingly.

[0035] Furthermore, if the embodiments of this utility model 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 use of "and / or" or "and / or" throughout the text includes three parallel solutions. For example, "A and / or B" includes solution A, solution B, or a solution where both A and B are satisfied simultaneously. Furthermore, 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. When 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 utility model.

[0036] Currently, in order to increase the magnetic flux of the stator core, permanent magnet motors in existing technology generally lengthen the stator teeth. However, this leads to a smaller rotor outer diameter, resulting in a smaller rotor moment of inertia. Consequently, the rotor may be more prone to speed fluctuations or slight vibrations during operation, affecting the overall stable operation of the equipment. Moreover, the rotor lamination structure design and magnetic flux distribution in existing permanent magnet motors are unreasonable, resulting in a large amount of magnetic leakage and low motor efficiency.

[0037] To solve the above problems, this utility model proposes a rotor 10.

[0038] Please see Figures 1 to 6In one embodiment of this utility model, the rotor 10 includes a rotor core 100 and a permanent magnet. The rotor core 100 includes a core body 110. At least one end of the core body 110 is provided with at least one second lamination 120. The core body 110 includes a plurality of first laminations 111 stacked along the axial direction. The first laminations 111 are provided with magnetic steel grooves 112. The length of the magnetic steel grooves 112 is d1. The second laminations 120 are provided with magnetic isolation grooves 121 corresponding to the magnetic steel grooves 112. The length of the magnetic isolation grooves 121 is d2. The width of the magnetic steel grooves 112 is W1. The width of the magnetic isolation grooves 121 is W2, satisfying: W1 < W2, d1 ≤ d2. The permanent magnet is disposed in the magnetic steel grooves 112.

[0039] The technical solution of this utility model is to provide at least one second lamination 120 at at least one end of the iron core body 110 with permanent magnets, which can increase the weight of the rotor iron core 100 and thus increase the moment of inertia of the rotor 10. Secondly, the width W2 of the magnetic isolation groove 121 of the second lamination 120 is greater than the width W1 of the magnet groove 112, which can increase the obstruction distance of the magnetic flux path at the end of the rotor 10, thereby reducing the axial leakage magnetic flux and allowing more magnetic flux to enter the stator iron core of the motor.

[0040] It should be noted that the magnetic steel channel 112 has a first channel side and a second channel side arranged opposite to each other along its width direction. W1 represents the perpendicular distance between the first channel side and the second channel side. That is, taking the center point of the first channel side as the first starting point, which is the intersection of the four diagonals of the first channel side, a perpendicular line is drawn through the first starting point to the second channel side. The intersection of this perpendicular line and the second channel side is the first ending point. W1 represents the distance between the first starting point and the first ending point. The magnetic steel channel 112 also has a third channel side and a fourth channel side arranged opposite to each other along its length direction. d1 represents the perpendicular distance between the third channel side and the fourth channel side. That is, taking the center point of the third channel side as the second starting point, which is the intersection of the four diagonals of the third channel side, a perpendicular line is drawn through the second starting point to the fourth channel side. The intersection of this perpendicular line and the fourth channel side is the second ending point. d1 represents the distance between the second starting point and the second ending point.

[0041] The magnetic shielding groove 121 has a fifth and a sixth side surface arranged opposite to each other along its width. W2 represents the perpendicular distance between the fifth and sixth side surfaces. Specifically, taking the center point of the fifth side surface as the third starting point (the intersection of the four diagonals of the fifth side surface), a perpendicular line is drawn through the third starting point to the sixth side surface; the intersection of this perpendicular line and the sixth side surface is the third ending point. W2 represents the distance between the third starting point and the third ending point. The magnetic shielding groove 121 also has a seventh and an eighth side surface arranged opposite to each other along its length. d2 represents the perpendicular distance between the seventh and eighth side surfaces. Specifically, taking the center point of the seventh side surface as the fourth starting point (the intersection of the four diagonals of the seventh side surface), a perpendicular line is drawn through the fourth starting point to the eighth side surface; the intersection of this perpendicular line and the eighth side surface is the fourth ending point. d2 represents the distance between the fourth starting point and the fourth ending point.

[0042] Furthermore, in this design, the length d1 of the magnetic slot 112 is less than or equal to the length d2 of the magnetic isolation slot 121, and the width W1 of the magnetic slot 112 is less than the width W2 of the magnetic isolation slot 121. Therefore, the area of ​​the magnetic slot 112 of the first lamination 111 is smaller than the area of ​​the magnetic isolation slot 121 of the second lamination 120. This increases the axial magnetic isolation effect of the second lamination 120. The larger the area of ​​the magnetic isolation slot 121, the stronger the air resistance path for the magnetic lines of force, thereby reducing axial magnetic flux leakage. Thus, this technical solution can increase the rotational inertia of the rotor core 100 while reducing axial magnetic flux leakage in the rotor core 100.

[0043] Reference Figure 10 , Figure 10 A comparison chart showing the COP of a compressor using the rotor provided by this invention with the COP of a compressor using conventional technology. (Refer to...) Figure 10 It can be seen that the COP of the compressor using the rotor provided by this utility model is greater than that of the compressor using traditional technology. Therefore, this solution can improve the energy efficiency of the compressor.

[0044] It should be noted that in this embodiment, the permanent magnet is only placed in the magnetic groove 112 of the first lamination 111, and the permanent magnet does not penetrate into the magnetic isolation groove 121 of the second lamination 120. This is because if the permanent magnet is placed in the second lamination 120, the magnetic flux will decrease significantly, thereby causing a significant decrease in motor performance.

[0045] Reference Figure 3 and Figure 4Furthermore, in this embodiment, at least one second lamination 120 is provided at both ends of the core body 110. Of course, in other embodiments, at least one second lamination 120 is provided at only one end of the core body 110; it can be understood that the second lamination 120 can be provided at one end of the core body 110 or at both ends, which can increase the rotational inertia of the rotor 10 while reducing the leakage of axial magnetic flux of the rotor core 100.

[0046] It should be noted that "at least one" refers to one or more, that is, it can be one, two, four, eight, etc., and the specific number of the second laminations 120 at the end of the core body 110 is not limited here. "Multiple" refers to two or more, that is, it can be two, three, eight, ten, etc.

[0047] Reference Figure 7 and Figure 8 In one embodiment, at least a portion of the magnet groove 112 of the first lamination 111 is provided with a first limiting protrusion 113. The first limiting protrusion 113 is used to press against the permanent magnet. It can be understood that this solution provides a first limiting protrusion 113 in at least a portion of the magnet groove 112 of the first lamination 111. In this way, the first limiting protrusion 113 can press against the permanent magnet, thereby limiting the displacement of the permanent magnet. On the one hand, it can prevent the permanent magnet from vibrating when the rotor 10 rotates, thereby improving the noise level of the motor and compressor. On the other hand, it can prevent the permanent magnet from displacing, thereby preventing the permanent magnet from entering the magnetic isolation groove 121.

[0048] In this embodiment, the first limiting protrusion 113 is provided on the wall of the magnet groove 112 of the first punch 111 in the width direction. Of course, this solution is not limited to this. In other embodiments, the first limiting protrusion 113 may also be provided on the wall of the magnet groove 112 of the first punch 111 in the length direction.

[0049] Furthermore, in this embodiment, the first limiting protrusion 113 is only provided on one of the groove walls of the magnet groove 112 of the first punch 111 in the width direction. In other embodiments, the first limiting protrusion 113 can also be provided on both groove walls of the magnet groove 112 of the first punch 111 in the thickness direction, so that the first limiting protrusion 113 can press against the permanent magnet on both sides in the thickness direction of the permanent magnet.

[0050] Furthermore, in this embodiment, only one first limiting protrusion 113 is provided on the magnet groove 112 of a first punch 111. Of course, this solution is not limited to this. Multiple first limiting protrusions 113 may also be provided on a magnet groove 112, such as two or three first limiting protrusions 113.

[0051] The first limiting protrusion 113 has a guide slope on its side wall at least in the insertion direction. This can press against the permanent magnet and guide the permanent magnet into the magnet slot 112 of the first punch 111 when it is inserted, which makes the installation of the permanent magnet easier.

[0052] Furthermore, in this embodiment, the outer peripheral surface of the first limiting protrusion 113 is generally arc-shaped. This not only presses against the permanent magnet but also guides the permanent magnet into the magnetic groove 112 of the first lamination 111 during insertion, making the installation of the permanent magnet easier. Secondly, it also makes the outer peripheral surface of the first limiting protrusion 113 smoother, reducing wear on the permanent magnet. Of course, this solution is not limited to this. In other embodiments, the first limiting protrusion 113 may have a guiding slope or guiding arc surface only on its sidewall in the insertion direction, while the sidewall that presses against the permanent magnet is flat.

[0053] In one embodiment, the thickness of the permanent magnet is T, and the first limiting protrusion 113 extends along the width direction of the magnet groove 112, with a maximum straight-line distance of L1, satisfying: 0 < W1 - L1 < T. This ensures that the first limiting protrusion 113 can press against the permanent magnet.

[0054] It should be noted that the permanent magnet has a first side and a second side distributed along its thickness direction. T represents the perpendicular distance between the first and second sides. That is, taking the center point of the first side as the fifth starting point (the intersection of the four diagonals of the first side), and drawing a perpendicular line from the fifth starting point to the second side, the intersection of this perpendicular line and the second side is the fifth ending point. T represents the distance between the fifth starting point and the fifth ending point. After the permanent magnet 200 is installed in the magnetic groove 112, the thickness direction of the permanent magnet 200 is parallel to the width direction of the magnetic groove 112. Assuming the first limiting protrusion 113 is located on the first groove side of the magnetic groove 112, taking the point of the first limiting protrusion 113 closest to the second groove side as the sixth starting point, and drawing a perpendicular line from the sixth starting point to the second groove side, the intersection of this perpendicular line and the second groove side is the sixth ending point. L1 represents the distance between the sixth starting point and the sixth ending point.

[0055] Reference Figure 3 , Figure 4 and Figure 9Optionally, at least a portion of the magnetic isolation groove 121 of the second lamination 120 has a limiting portion 122 on its groove wall, which is used to limit the end of the permanent magnet. It can be understood that the limiting portion 122 can restrict the axial displacement of the permanent magnet, preventing it from axially displacing from the magnetic groove 112 of the first lamination 111 into the magnetic isolation groove 121 of the second lamination 120. This eliminates the need for the motor end plate, simplifying the rotor 10, and also fixes the permanent magnet to prevent axial movement, resulting in better noise reduction. Of course, this solution is not limited to this. In other embodiments, if the limiting force of the first limiting protrusion 113 is large enough to prevent axial displacement of the permanent magnet, the limiting portion 122 may not be provided in the magnetic isolation groove 121.

[0056] Reference Figure 3 and Figure 4 Furthermore, in this embodiment, some of the magnetic isolation grooves 121 of the second laminations 120 have limiting portions 122 on their groove walls, while some of the magnetic isolation grooves 121 of the second laminations 120 do not have limiting portions 122. The second laminations 120 with limiting portions 122 are located close to the core body 110. The second laminations 120 with limiting portions 122 are designated as 123, and the second laminations 120 without limiting portions 122 are designated as 124. Of course, this solution is not limited to this. In other embodiments, all magnetic isolation grooves 121 of the second laminations 120 may have limiting portions 122.

[0057] Optionally, in this embodiment, both ends of the core body 110 are provided with second laminations 120, but only one end of the second lamination 120 has a magnetic isolation groove 121 with a limiting part 122, and at least part of the magnetic isolation groove 121 has a limiting part 122.

[0058] In one embodiment, the limiting part 122 is configured as a second limiting protrusion, and such a limiting part 122 has a simple structure and is easy to process and form.

[0059] It should be noted that the limiting part 122 needs to limit the end of the permanent magnet. Therefore, the maximum straight distance of the second limiting protrusion needs to be greater than one-third of the thickness of the permanent magnet.

[0060] In the second embodiment, the limiting part 122 is configured as a limiting rib, which connects the two groove walls of the magnetic isolation groove 121 arranged along the width direction, so as to better limit the displacement of the permanent magnet.

[0061] Furthermore, in this embodiment, at least one limiting part 122 is provided on the groove wall of the magnetic shielding groove 121, and the specific number of limiting parts 122 is not limited here.

[0062] Reference Figure 1Optionally, the rotor core 100 is provided with rivet holes 130, the distance from the rivet holes 130 to the magnet slots 112 is X1, and X1 satisfies: X1 > 0.5 mm; the distance from the rivet holes 130 to the magnetic isolation slots 121 is X2, and X2 satisfies: X2 > 0.5 mm; it can be understood that the distance between the rivet holes 130 and the magnet slots of the first lamination 111 and the magnetic isolation slots 121 of the second lamination 120 is consistent, so as to ensure that the permanent magnet is not riveted to the maximum extent during the riveting process.

[0063] It should be noted that the point of the rivet hole 130 closest to the magnetic groove 112 is taken as the seventh starting point. A perpendicular line is drawn from the seventh starting point to the wall of the magnetic groove 112. The intersection of this perpendicular line and the wall of the magnetic groove 112 is the seventh ending point. X1 represents the distance between the seventh starting point and the seventh ending point. The point of the rivet hole 130 closest to the magnetic isolation groove 121 is taken as the eighth starting point. A perpendicular line is drawn from the eighth starting point to the wall of the magnetic isolation groove 121. The intersection of this perpendicular line and the wall of the magnetic isolation groove 121 is the eighth ending point. X2 represents the distance between the eighth starting point and the eighth ending point.

[0064] In one embodiment, the magnetic steel groove 112 and the magnetic isolation groove 121 are in the shape of a straight line, a V-shape, or a U-shape. It can be understood that the shape of the magnetic steel groove 112 can be a straight line or other shapes composed of straight lines; for example, but not limited to straight lines forming a V-shape or a U-shape.

[0065] In this embodiment, the magnet slot 112 is V-shaped. This is because the V-shaped magnet slot 112 can effectively increase the power density of the motor. By optimizing the magnetic field distribution, the motor can output higher power within the same volume. The V-shaped design also reduces magnetic field leakage, improving motor efficiency and reducing energy loss. The V-shaped magnet slot 112 also helps enhance the motor's torque characteristics, increasing its starting torque and overload capacity.

[0066] In the second embodiment, the magnetic steel groove 112 is in a straight line shape because this type of magnetic steel groove 112 has a simple structure: the design of the straight-line magnetic steel groove 112 is simple and straightforward, easy to process and manufacture, and can reduce production costs and production cycle. Moreover, the straight-line magnetic steel groove 112 has good fixation: it can provide a better fixing effect, protect the permanent magnet from impact, and effectively resist centrifugal force, improving the stability of the permanent magnet. This shape of the magnetic steel groove 112 is conducive to heat dissipation, improving the heat dissipation efficiency of the permanent magnet and preventing damage to the permanent magnet due to overheating.

[0067] In the third embodiment, the magnet slot 112 is U-shaped. This is because the U-shaped slot design can effectively reduce magnetic flux leakage and improve the efficiency and power factor of the motor. The U-shaped magnet slot 112 has a compact structure, making it suitable for applications with limited space, and can improve the performance of the motor without increasing its size.

[0068] This utility model also proposes an electric motor, which includes a stator and a rotor. The specific structure of the rotor is as described in the above embodiments. Since this motor adopts all the technical solutions of all the above embodiments, it has at least all the beneficial effects brought about by the technical solutions of the above embodiments, which will not be described in detail here. The rotor is rotatably disposed within the stator.

[0069] Optionally, the maximum outer diameter of the stator is D0, and the maximum outer diameter of the rotor is D1, satisfying: 0.48 < D1 / D0 < 0.58. It can be understood that if the ratio of D1 / D0 is large, the rotor's moment of inertia is large, and it is not necessary to increase the rotor's axial length to increase the moment of inertia. If the ratio of D1 / D0 is small, the moment of inertia is too small, and increasing it axially would be too costly, while also increasing the height of the compressor. This solution limits the ratio of D1 / D0 to between 0.48 and 0.58, which balances the relationship between inertia and axial dimensions. This ensures sufficient inertia while reducing production costs, resulting in optimal motor performance.

[0070] This utility model also proposes a compressor, which includes a motor. The specific structure of the motor is as described in the above embodiments. Since this compressor adopts all the technical solutions of all the above embodiments, it has at least all the beneficial effects brought about by the technical solutions of the above embodiments, which will not be described in detail here.

[0071] The above description is merely an exemplary embodiment of the present utility model and does not limit the patent scope of the present utility model. Any equivalent structural transformations made based on the technical concept of the present utility model and the contents of the present utility model specification and drawings, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present utility model.

Claims

1. A rotor characterized by, The rotor core comprises a core body, at least one second punching sheet is arranged at one end of the core body, the core body comprises a plurality of first punching sheets arranged in an axial direction, the first punching sheet is provided with a magnetic steel slot, the length of the magnetic steel slot is d1, the second punching sheet is provided with a magnetic isolation slot corresponding to the magnetic steel slot, the length of the magnetic isolation slot is d2, the width of the magnetic steel slot is W1, the width of the magnetic isolation slot is W2, and the following conditions are met: W1 < W2, d1 ≤ d2, and A permanent magnet is arranged in the magnetic steel slot. At least one second punching sheet is arranged at both ends of the core body.

2. The rotor of claim 1, wherein The magnetic steel slot of at least part of the first punching sheet is provided with a first limiting protrusion for pressing the permanent magnet.

3. The rotor of claim 1, wherein The thickness of the permanent magnet is T, the first limiting protrusion extends in the width direction of the magnetic steel slot, and the maximum linear distance of the extension is L1, and the following condition is met: 0 < W1-L1 < T.

4. The rotor of claim 3, wherein The slot wall of the magnetic isolation slot of at least part of the second punching sheet is provided with a limiting part for limiting the end of the permanent magnet.

5. The rotor of claim 1, wherein The limiting part is configured as a second limiting protrusion; or 6. The rotor of claim 5, wherein The limiting part is configured as a limiting rib connected to the two slot walls arranged in the width direction of the magnetic isolation slot. The rotor core is provided with a rivet hole, the distance from the rivet hole to the magnetic steel slot is X1, and the following condition is met: X1 > 0.5 mm; the distance from the rivet hole to the magnetic isolation slot is X2, and the following condition is met: X2 > 0.5 mm.

7. The rotor of claim 1, wherein The shapes of the magnetic steel slot and the magnetic isolation slot are in the form of a straight line, V or U.

8. A rotor as claimed in any one of claims 1 to 7, characterised in that The motor comprises a stator and a rotor as claimed in any one of claims 1 to 7, and the rotor is arranged in rotation in the stator.

9. An electric machine characterized by The maximum outer diameter of the stator is D0, the maximum outer diameter of the rotor is D1, and the following condition is met: 0.48 < D1 / D0 < 0.

58.

10. The electric machine of claim 9, wherein, The motor comprises a stator and a rotor as claimed in any one of claims 1 to 7, and the rotor is arranged in rotation in the stator.

11. A compressor characterized by, The maximum outer diameter of the stator is D0, the maximum outer diameter of the rotor is D1, and the following condition is met: 0.48 < D1 / D0 < 0.58.

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