Rotor structure and motor

Abstract

The utility model provides a rotor structure and a motor. The rotor structure comprises a rotor core and permanent magnets, the rotor core comprises a plurality of filling grooves, a plurality of permanent magnet grooves and a plurality of air grooves, the permanent magnets are arranged in the permanent magnet grooves, the filling grooves are distributed in the peripheral side of the rotor core, the filling grooves comprise q-axis filling grooves and d-axis filling grooves, and the q-axis filling grooves and the d-axis filling grooves are distributed in the direction away from the d axis. The permanent magnet grooves, the air grooves and the q-axis filling grooves are sequentially arranged, connecting ribs are arranged between the q-axis filling grooves and the adjacent air grooves, connecting ribs are arranged between at least part of the air grooves and the permanent magnet grooves, the q-axis filling grooves, the air grooves and the permanent magnet grooves which are located on the same layer form a layer of magnetic flux barriers, and the multiple layers of magnetic flux barriers are arranged at intervals in the d-axis direction. The number of the connecting ribs of the magnetic flux barrier located on the outermost side in the radial direction in the d-axis direction is larger than the number of the connecting ribs of the magnetic flux barriers located on other layers. According to the rotor structure of the utility model, the anti-demagnetization capability of the motor can be improved, and the operation reliability of the motor can be enhanced.

Description

Technical Field

[0001] The utility model relates to the technical field of motors, and in particular to a rotor structure and a motor. Background Art

[0002] Permanent magnet-assisted synchronous reluctance motors have the advantages of high efficiency, high power factor, high torque density, wide response frequency, and no need for complex couplers. They are widely used in industry and scientific research fields. However, there is a self-starting problem, mainly because of rotor copper loss, which reduces the starting torque of the motor. The rotor copper loss is large, affecting the efficiency of the motor.

[0003] The self-starting permanent magnet assisted synchronous reluctance motor is based on the permanent magnet assisted synchronous reluctance motor, combines the advantages of the asynchronous motor, uses the asynchronous torque generated by the rotor cage bars to achieve self-starting, and has no rotor copper loss, so it has higher efficiency.

[0004] Self-starting permanent magnet synchronous motors are directly connected to the power grid for start-up. The starting current is large and demagnetization problems are prone to occur. Especially for two-pole motors, the stator demagnetization field is concentrated and the rotor space is limited, making it difficult to effectively balance demagnetization and motor reliability. Summary of the Invention

[0005] The main purpose of the utility model is to provide a rotor structure and a motor, which can improve the anti-demagnetization ability of the motor and enhance the operating reliability of the motor.

[0006] In order to achieve the above-mentioned purpose, according to one aspect of the present invention, a rotor structure is provided, including a rotor core and permanent magnets, the rotor core including multiple filling slots, multiple permanent magnet slots and multiple air slots, the permanent magnets are arranged in the permanent magnet slots, the filling slots are distributed on the outer peripheral side of the rotor core, the filling slots include q-axis filling slots and d-axis filling slots, along the direction away from the d-axis, the permanent magnet slots, the air slots and the q-axis filling slots are arranged in sequence, and connecting ribs are provided between each q-axis filling slot and the adjacent air slots, and connecting ribs are provided between at least some of the air slots and the permanent magnet slots, the q-axis filling slots, the air slots and the permanent magnet slots located in the same layer form a layer of magnetic flux barriers, the multiple layers of magnetic flux barriers are arranged at intervals along the d-axis direction, and the number of connecting ribs of the magnetic flux barriers located radially outermost along the d-axis direction is greater than the number of connecting ribs of the magnetic flux barriers located in other layers.

[0007] Furthermore, each flux barrier is provided with connecting ribs on the d-axis. In the flux barrier located radially outermost along the d-axis direction, connecting ribs are provided between the permanent magnet slots and the air slots. In the flux barriers located in other layers, the permanent magnet slots are connected to the air slots.

[0008] Furthermore, in the magnetic flux barrier located radially outermost along the d-axis direction, the width of the connecting rib between the permanent magnet slot and the air slot and the width of the connecting rib located on the d-axis are w5, the thickness of the permanent magnet located in the permanent magnet slot is w1, and 0.2*w1≤w5≤0.5*w1.

[0009] Furthermore, the thickness of the permanent magnet located radially outermost along the d-axis direction is w1, the thickness of the permanent magnet located radially innermost is w3, and the thickness of the permanent magnet located in the middle layer is w2, w1>w2≥w3.

[0010] Furthermore, w1≥1.2*w2.

[0011] Furthermore, the permanent magnet slots in different layers on the same side of the d-axis are parallel to each other, each layer of the flux barrier includes two rectangular permanent magnets, and the two permanent magnets in the same layer are symmetrical about the d-axis.

[0012] Furthermore, each layer of the flux barrier includes two permanent magnets. Under the same pole, in a cross section perpendicular to the central axis of the rotor core, the angle formed by the line connecting the endpoints of the circumferential outer edges of the two permanent magnets located in the same layer and the center of the rotor core is the pole arc angle β, and the pole arc angle β formed by each layer of permanent magnets is less than 90°.

[0013] Furthermore, 40°≤β≤75°; and / or, along the radial direction from the inside to the outside on the d-axis, the pole arc angle β formed by each layer of permanent magnets decreases.

[0014] Furthermore, the permanent magnet slots are rectangular slots, the permanent magnet slots in the same layer of flux barriers are symmetrical about the d-axis, the angle between two permanent magnet slots symmetrical about the d-axis is α, and 140°≤α≤180°.

[0015] Furthermore, 150°≤α≤170°.

[0016] Furthermore, the width of the magnetic conductive channel between adjacent layers of permanent magnets on the same side of the q-axis is k1, and the width of the magnetic conductive channel between adjacent q-axis filling slots is k2, where k2>k1.

[0017] Furthermore, the minimum width between the permanent magnet slots in different layers is kmin, the width of the permanent magnet in the corresponding layer is wd, and kmin>1.8wd.

[0018] Furthermore, the minimum diameter of the distribution circle of the q-axis filling groove is D1, the minimum diameter of the distribution circle of the d-axis filling groove is D2, and D2≥D1.

[0019] Furthermore, the outer diameter of the rotor core is D, the minimum diameter of the distribution circle of the d-axis filling slot is D2, and 0.8D≤D2≤0.9D.

[0020] Furthermore, the minimum distance between adjacent d-axis filling slots is w4, the thickness of the permanent magnet located radially outermost along the d-axis direction is w1, and w4≥w1.

[0021] Furthermore, the thickness of the air slot at one end close to the permanent magnet slot is L11, and the thickness of the air slot at one end close to the q-axis filling slot is L12, and L12 ≥ L11.

[0022] Furthermore, the flux barrier is three-layered. In a cross section perpendicular to the central axis of the rotor core, both ends of the flux barrier are parallel to the q-axis, the middle of the flux barrier protrudes toward the outer circle of the rotor core, and the angle formed by the line connecting the outer ends of the q-axis filling slots at both ends of the flux barrier located at the radially outermost ends along the d-axis direction and the center of the rotor core is γ, and γ ≥ 90°.

[0023] Furthermore, 90°≤γ≤120°.

[0024] Furthermore, rivet holes are provided on the rotor core, baffles and end rings are provided at both ends of the rotor core, the filling grooves are filled with conductive non-magnetic material, the conductive non-magnetic material is short-circuited through the end rings to form a rotor cage, and the baffles are fixedly connected by rivets provided in the rivet holes; and / or, the permanent magnet slots are filled with resin.

[0025] According to another aspect of the present invention, a motor is provided, comprising a stator structure and a rotor structure. The rotor structure is the above-mentioned rotor structure, and the stator structure is sleeved on the outer circumference of the rotor structure.

[0026] Furthermore, in a cross section perpendicular to the central axis of the rotor core, the width of the connecting rib between the q-axis filling slot and the outer circle of the rotor core is w6, the air gap width between the stator structure and the rotor structure is δ, 0≤w6≤2δ, and the width of the connecting rib between the q-axis filling slot and the air slot is w7, 0≤w7≤2δ.

[0027] According to the technical solution of the present invention, the rotor structure includes a rotor core and permanent magnets. The rotor core includes multiple filling slots, multiple permanent magnet slots and multiple air slots. The permanent magnets are arranged in the permanent magnet slots. The filling slots are distributed on the outer peripheral side of the rotor core. The filling slots include q-axis filling slots and d-axis filling slots. The permanent magnet slots, air slots and q-axis filling slots are arranged in sequence along the direction away from the d-axis. Connecting ribs are provided between each q-axis filling slot and the adjacent air slots. Connecting ribs are provided between at least some of the air slots and the permanent magnet slots. The q-axis filling slots, air slots and permanent magnet slots located in the same layer form a layer of magnetic flux barriers. The multiple layers of magnetic flux barriers are arranged at intervals along the d-axis direction. The number of connecting ribs of the magnetic flux barriers located radially outermost along the d-axis direction is greater than the number of connecting ribs of the magnetic flux barriers located in other layers. Since the outermost permanent magnets are prone to demagnetization problems, the present application changes the original direction of the magnetic lines of force by setting multiple connecting ribs between the outermost permanent magnet slots and the air slots, so that the magnetic lines of force that originally passed through the permanent magnets pass through the connecting ribs as much as possible. Since the magnetic permeability of the silicon steel sheets forming the rotor core is much greater than that of the permanent magnets and air, the magnetic lines of force will try to go to places with low magnetic resistance. Where the magnetic permeability is large, the magnetic resistance is small. Therefore, increasing the number of connecting ribs of the outer magnetic barrier is equivalent to setting a path for the outer permanent magnets, so that the magnetic lines of force no longer pass through the permanent magnets and air, thereby increasing the demagnetization resistance of the permanent magnets. The rotor structure is designed with multiple connecting ribs for the magnetic flux barrier located in the outermost layer, so that the number of connecting ribs of the outermost magnetic flux barrier is the largest. This not only increases the mechanical strength of the rotor structure, but also can use the added connecting ribs to improve the demagnetization problem of the permanent magnets and improve the demagnetization resistance of the permanent magnets, thereby effectively enhancing the reliability of the motor operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The drawings constituting part of this application are provided to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are provided to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0029] Figure 1 The figure shows the size structure of the rotor structure of the embodiment of the present utility model;

[0030] Figure 2 The figure shows the size structure of the rotor structure of the embodiment of the present utility model;

[0031] Figure 3 A schematic structural diagram of a rotor core of a rotor structure according to an embodiment of the present invention is shown;

[0032] Figure 4 A diagram showing the dimensions of a squirrel cage structure of a rotor structure according to an embodiment of the present invention;

[0033] Figure 5Shows the assembly structure diagram of the baffle and end ring of the rotor structure of an embodiment of the present utility model;

[0034] Figure 6 A diagram showing the plastic packaging structure of the rotor structure of an embodiment of the present utility model is shown;

[0035] Figure 7 A comparison diagram of the magnetic flux density of the outermost permanent magnets of the motor of the embodiment of the present utility model and the motor of the prior art during the starting process is shown;

[0036] Figure 8 A torque comparison diagram showing the motor of the embodiment of the present utility model and the motor of the prior art; and

[0037] Figure 9 A comparison diagram of the efficiency of the motor according to the embodiment of the present utility model and the motor according to the prior art is shown.

[0038] The above drawings include the following reference numerals:

[0039] 1. Rotor structure; 2. Rotor core; 3. Rotor punching; 4. Filling slot; 41. Q-axis filling slot; 42. D-axis filling slot; 5. Permanent magnet slot; 6. Air slot; 7. Permanent magnet; 8. Connecting rib; 9. Rivet hole; 10. Baffle; 11. End ring; 12. Plastic encapsulation compound. DETAILED DESCRIPTION

[0040] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments in this application can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0041] See also Figures 1 to 9 As shown, according to an embodiment of the present invention, the rotor structure includes a rotor core 2 and a permanent magnet 7, the rotor core 2 includes a plurality of filling slots 4, a plurality of permanent magnet slots 5 and a plurality of air slots 6, the permanent magnets 7 are arranged in the permanent magnet slots 5, the filling slots 4 are distributed on the outer peripheral side of the rotor core 2, the filling slots 4 include q-axis filling slots 41 and d-axis filling slots 42, along the direction away from the d-axis, the permanent magnet slots 5, the air slots 6 and the q-axis filling slots 41 are arranged in sequence, and a connecting rib 8 is provided between each q-axis filling slot 41 and the adjacent air slot 6, and a connecting rib 8 is provided between at least some of the air slots 6 and the permanent magnet slots 5, the q-axis filling slots 41, the air slots 6 and the permanent magnet slots 5 located in the same layer form a layer of magnetic flux barriers, and the multiple layers of magnetic flux barriers are arranged at intervals along the d-axis direction, and the number of connecting ribs of the magnetic flux barriers located radially outermost along the d-axis direction is greater than the number of connecting ribs of the magnetic flux barriers located in other layers.

[0042] Since the outermost permanent magnets are prone to demagnetization problems, the present application changes the original direction of the magnetic lines of force by setting multiple connecting ribs 8 between the outermost permanent magnet slots 5 and the air slots 6, so as to make the magnetic lines of force that originally passed through the permanent magnets pass through the connecting ribs 8 as much as possible. Since the magnetic permeability of the silicon steel sheets forming the rotor core 2 is much greater than that of the permanent magnets and air, the magnetic lines of force will go to places with low magnetic resistance as much as possible, and the magnetic resistance is small where the magnetic permeability is large. Therefore, increasing the number of outer magnetic barrier connecting ribs is equivalent to setting a path for the outer permanent magnets, so that the magnetic lines of force no longer pass through the permanent magnets 7 and the air, thereby increasing the anti-demagnetization ability of the permanent magnets 7.

[0043] The rotor structure is designed with multiple connecting ribs for the magnetic flux barrier located in the outermost layer, so that the number of connecting ribs 8 of the magnetic flux barrier in the outermost layer is the largest. This not only increases the mechanical strength of the rotor structure, but also can utilize the added connecting ribs 8 to improve the demagnetization problem of the permanent magnet 7 and enhance the anti-demagnetization ability of the permanent magnet 7, thereby effectively enhancing the reliability of the motor operation.

[0044] In this embodiment, the rotor core 2 is formed by stacking multiple rotor punchings 3, and each rotor punching 3 is provided with multiple filling slots 4, permanent magnet slots 5 and air slots 6. The filling slots 4 include q-axis filling slots 41 and d-axis filling slots 42. Connecting ribs 8 are provided between the q-axis filling slots 41 and the air slots 6, and connecting ribs 8 are provided between a part of the permanent magnet slots 5 and the air slots 6.

[0045] In one embodiment, each flux barrier is provided with a connecting rib 8 on the d-axis. In the flux barrier located radially outermost along the d-axis direction, a connecting rib 8 is provided between the permanent magnet slot 5 and the air slot 6. In the flux barriers located in other layers, the permanent magnet slot 5 is connected to the air slot 6.

[0046] In this embodiment, connecting ribs 8 located between the permanent magnet slots 5 and the air slots 6 of the outermost magnetic flux barrier separate the permanent magnets 7 in the outermost magnetic flux barrier from the air slots 6. In the remaining magnetic flux barriers, the permanent magnet slots 5 are connected to the air slots 6. The presence of connecting ribs 8 between the permanent magnet slots 5 and the air slots 6 increases the number of connecting ribs 8 in the radially outermost magnetic flux barrier, thereby enhancing the mechanical strength of the rotor structure located in the radially outermost region.

[0047] In one embodiment, in the radially outermost magnetic flux barrier along the d-axis direction, the width of the connecting rib 8 between the permanent magnet slot 5 and the air slot 6 and the width of the connecting rib 8 located on the d-axis are w5, the thickness of the permanent magnet 7 located in the permanent magnet slot 5 is w1, and 0.2*w1≤w5≤0.5*w1.

[0048] Through the above arrangement, the anti-demagnetization capability of the permanent magnet 7 under high current can be improved while ensuring the normal operation of the rotor structure and low magnetic leakage within a certain rib width range.

[0049] In one embodiment, the thickness of the radially outermost permanent magnet 7 along the d-axis direction is w1, the thickness of the radially innermost permanent magnet 7 is w3, and the thickness of the intermediate permanent magnet 7 is w2, w1>w2≥w3.

[0050] In one embodiment, w1 ≥ 1.2*w2.

[0051] In one embodiment, the permanent magnet slots 5 in different layers on the same side of the d-axis are parallel to each other, each layer of flux barriers includes two rectangular permanent magnets 7 , and the two permanent magnets 7 in the same layer are symmetrical about the d-axis.

[0052] Inserting permanent magnets 7 into the permanent magnet slots 5, distributing the permanent magnets 7 according to the demagnetization characteristics of the motor, and setting the thickness of the outer layer of permanent magnets 7 located at the radially outermost periphery along the d-axis direction to be greater than the thickness of the inner layer of permanent magnets 7, can improve the anti-demagnetization ability of the permanent magnets 7, while ensuring the usage of each layer of permanent magnets, avoiding local improvement of the anti-demagnetization performance, and improving the consistency of the anti-demagnetization of the permanent magnets.

[0053] In one embodiment, each layer of the flux barrier includes two permanent magnets 7. Under the same pole, in a cross section perpendicular to the central axis of the rotor core 2, the angle formed by the line connecting the endpoints of the circumferential outer edges of the two permanent magnets 7 located in the same layer and the center of the rotor core 2 is the pole arc angle β. The pole arc angle β formed by each layer of the permanent magnets 7 is less than 90°.

[0054] In one embodiment, 40°≤β≤75°.

[0055] In one embodiment, along the radial direction from the inside to the outside on the d-axis, the pole arc angle β formed by each layer of permanent magnets 7 decreases.

[0056] By reasonably setting the variation range of the pole arc angle of the permanent magnet 7 , the utilization rate of the permanent magnet can be improved and the output capacity of the motor can be increased.

[0057] In one embodiment, the permanent magnet slots 5 are rectangular slots. The permanent magnet slots 5 in the same layer of flux barriers are symmetrical about the d axis. The angle between two permanent magnet slots 5 symmetrical about the d axis is α, and 140°≤α≤180°.

[0058] In one embodiment, 150°≤α≤170°.

[0059] By limiting the angle range between two adjacent permanent magnet slots 5 , the space of the two-pole rotor can be fully utilized, the utilization rate of the permanent magnet can be improved, and at the same time, the magnetic field circuit of the rotor can be ensured, thereby improving the output capacity of the motor.

[0060] In one embodiment, the extension direction of the q-axis filling slot 41 is roughly parallel to the q-axis; the center line perpendicular to the magnetic flux barrier is the d-axis, and the center axis perpendicular to the d-axis is the q-axis; the purpose of this setting is to use the extension direction of the q-axis filling slot 41 to reduce the impact of the filling slot on the magnetic circuit, ensure the output of the motor, and the filling slot is used to achieve self-starting of the motor.

[0061] In one embodiment, the width of the magnetic channel between adjacent layers of permanent magnets 7 on the same side of the q-axis is k1, and the width of the magnetic channel between adjacent q-axis filling slots 41 is k2. The width k2 between the q-axis filling slots is greater than the width k1 between the permanent magnet slots, i.e., k2>k1. This arrangement prevents overloading of the magnetic channel between the permanent magnets, avoids rotor saturation, maximizes permanent magnet torque and reluctance torque, and improves the motor's output performance.

[0062] In one embodiment, the minimum width between permanent magnet slots 5 in different layers is kmin, and the width of the permanent magnets 7 in the corresponding layer is wd, where kmin>1.8*wd. This setting is intended to ensure sufficient width between permanent magnet slots 5, while also ensuring sufficient magnetic path space for the rotor, reducing rotor saturation and improving motor output performance.

[0063] In one embodiment, the minimum diameter of the distribution circle of the q-axis filling groove 41 is D1, and the minimum diameter of the distribution circle of the d-axis filling groove 42 is D2, where D2 ≥ D1.

[0064] The minimum diameter of the q-axis filling slot 41 is D1, and the minimum diameter of the d-axis filling slot 42 is D2. The minimum distance from the d-axis filling slot 42 to the rotor center must be greater than or equal to the minimum distance from the q-axis filling slot 41 to the rotor center, that is, the minimum diameter of the d-axis filling slot 42 is greater than or equal to the minimum diameter of the q-axis filling slot 41, that is, D2 ≥ D1. Reasonable setting of the width between the d-axis filling slots 42 at both ends of the same diameter in the d-axis direction ensures a certain amount of rotor core design space, allowing the arrangement of multiple layers of permanent magnets and magnetic channels, effectively avoiding magnetic circuit saturation. The minimum diameter of the q-axis filling slot 41 refers to the diameter of the circle on the side of the q-axis filling slot 41 closest to the rotating shaft, and the minimum diameter of the d-axis filling slot 42 refers to the diameter of the circle on the side of the d-axis filling slot 42 closest to the rotating shaft.

[0065] In one embodiment, the outer diameter of the rotor core 2 is D, the minimum diameter of the distribution circle of the d-axis filling slot 42 is D2, and 0.8D≤D2≤0.9D. This configuration further ensures that there is sufficient rotor space in the d-axis direction to properly arrange the multiple layers of permanent magnets 7 and magnetic conductive channels, thereby reducing the impact of rotor magnetic circuit saturation.

[0066] In one embodiment, the minimum distance between adjacent d-axis filling slots 42 is w4, the thickness of the permanent magnet 7 radially outermost along the d-axis is w1, and w4 ≥ w1. This configuration prevents the gaps between d-axis filling slots 42 from being too small, resulting in a narrow magnetic conduction path, which would hinder the magnetic field of the permanent magnet from entering the air gap and reduce the utilization rate of the permanent magnet.

[0067] In one embodiment, the thickness of the air slot 6 at one end close to the permanent magnet slot 5 is L11, and the thickness of the air slot 6 at one end close to the q-axis filling slot 41 is L12, where L12 ≥ L11.

[0068] The air slot 6 is located between the permanent magnet slot 5 and the q-axis filling slot 41. The shape of the air slot 6 is arc-shaped, rectangular, boot-shaped or other shapes. The thickness of the air slot 6 near one end of the permanent magnet slot 5 is L11, and the thickness of the air slot 6 near one end of the q-axis filling slot 41 is L12. The thickness of the air slot near the filling slot end is greater than or equal to the thickness of the air slot near the permanent magnet slot end, that is, L12 ≥ L11. The purpose of this setting is to make full use of the rotor space, increase the permanent magnet torque and reluctance torque, and improve the torque output capacity.

[0069] In one embodiment, the flux barrier is three-layered. In a cross section perpendicular to the central axis of the rotor core 2, the two ends of the flux barrier are parallel to the q-axis, the middle of the flux barrier protrudes toward the outer circle of the rotor core 2, and the angle formed by the line connecting the outer ends of the q-axis filling slots 41 at both ends of the radially outermost flux barrier along the d-axis direction and the center of the rotor core 2 is γ, and γ ≥ 90°.

[0070] In one embodiment, 90°≤γ≤120°.

[0071] The purpose of the above-mentioned setting is to enable the formed flux barrier to increase the salient pole difference, thereby generating a larger reluctance torque and improving the output performance of the motor.

[0072] In one embodiment, a rivet hole 9 is provided on the rotor core 2, and baffles 10 and end rings 11 are provided at both ends of the rotor core 2. The filling groove 4 is filled with conductive non-magnetic material, and the conductive non-magnetic material is short-circuited through the end ring 11 to form a rotor cage. The baffle 10 is fixedly connected by rivets set in the rivet hole 9.

[0073] In this embodiment, the baffle 10 is arranged at both ends of the rotor core 2 and is riveted to the rotor core 2 by rivets arranged in the rivet holes 9. Then, the end ring 11 is arranged on the outer peripheral side of the baffle 10, and the conductive non-magnetic material is filled in the filling groove 4, so that the conductive non-magnetic material in the filling groove 4 is short-circuited through the end ring 11. Since the filling groove 4 is arranged on the outer peripheral side of the rotor core 2 and arranged along the circumferential direction, the end ring 11 can cover the conductive non-magnetic material in the filling groove to achieve short-circuiting, forming a squirrel cage structure to generate asynchronous torque so that the motor can self-start, while preventing the permanent magnet from sliding and generating vibration noise.

[0074] In one embodiment, the permanent magnet slots 5 are filled with resin. The resin can fill the gap between the permanent magnet slots 5 and the permanent magnets 7, thereby fixing the permanent magnets 7 and preventing them from moving.

[0075] In one embodiment, baffles 10 are mounted at both ends of the rotor. The baffles 10 are made of a non-magnetic material, such as stainless steel. The outer diameter of the baffles 10 is smaller than the inner diameter of the end rings 11, and the inner diameter of the baffles 10 is larger than the outer diameter of the shaft hole of the rotor core 2. The baffles 10 are fixed to both ends of the rotor core 2 by screws. Alternatively, the rotor permanent magnet slots and air slots are filled with a non-conductive and non-magnetic material, such as resin, and then plastic-encapsulated, so that the two ends of the rotor core 2 are fixed by the end rings 11 and the plastic encapsulation material 12. The purpose of this arrangement is to secure the permanent magnets 7 and prevent them from vibrating, sliding, or falling out.

[0076] In one embodiment, a baffle 10, an end ring 11 and a molding compound 12 are respectively provided at both ends of the rotor core 2, wherein the baffle 10 is located on the inner circumference of the end ring 11, and the molding compound 12 is molded on the outer side of the baffle 10 to form a seal for the end of the motor.

[0077] According to an embodiment of the present invention, the motor includes a stator structure and a rotor structure 1 . The rotor structure 1 is the above-mentioned rotor structure, and the stator structure is sleeved on the outer circumference of the rotor structure 1 .

[0078] In one embodiment, in a cross section perpendicular to the central axis of the rotor core 2, the width of the connecting rib 8 between the q-axis filling slot 41 and the outer circumference of the rotor core 2 is w6, the width of the air gap between the stator structure and the rotor structure 1 is δ, 0≤w6≤2δ, and the width of the connecting rib 8 between the q-axis filling slot 41 and the air slot 6 is w7, 0≤w7≤2δ. This configuration is intended to ensure the mechanical strength of the rotor structure. Furthermore, smaller rib widths, or the absence of rib widths, can reduce magnetic flux leakage from the motor and improve its output capacity.

[0079] Figure 7The figure shows the minimum magnetic flux density of the self-starting permanent magnet assisted synchronous reluctance motor during the starting process. Compared with the prior art, the motor of the embodiment of the utility model can significantly improve the anti-demagnetization ability of the permanent magnet by increasing the number of outer magnetic barrier ribs.

[0080] Figure 8 The figure shows the output torque corresponding to different permanent magnet slot angles of the self-starting permanent magnet assisted synchronous reluctance motor. When the permanent magnet slot angle is 140°≤α≤180°, the motor of the embodiment of the present invention has a higher output torque value, and when the permanent magnet slot angle is 150°≤α≤170°, the output torque value of the motor of the embodiment of the present invention is significantly improved, thereby improving the output capacity of the motor.

[0081] Figure 9 The figure shows the efficiency corresponding to different output torques of the self-starting permanent magnet assisted synchronous reluctance motor. When the output torque is the same, the efficiency of the motor of the embodiment of the utility model is significantly higher than the efficiency of the motor of the prior art. As the output torque gradually increases, the difference between the efficiency of the motor of the embodiment of the utility model and the efficiency of the motor of the prior art also gradually increases, and the efficiency is significantly improved.

[0082] 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.

[0083] It should be noted that the terms "first," "second," and the like in the specification and claims of this application and the accompanying drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or precedence. It should be understood that the terms used in this manner are interchangeable where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than that illustrated or described herein.

[0084] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Those skilled in the art will readily appreciate that the present invention is susceptible to various modifications and variations. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A rotor structure, characterized in that: The invention comprises a rotor core (2) and a permanent magnet (7), wherein the rotor core (2) comprises a plurality of filling slots (4), a plurality of permanent magnet slots (5) and a plurality of air slots (6), wherein the permanent magnets (7) are arranged in the permanent magnet slots (5), the filling slots (4) are distributed on the outer peripheral side of the rotor core (2), the filling slots (4) comprise q-axis filling slots (41) and d-axis filling slots (42), and along a direction away from the d-axis, the permanent magnet slots (5), the air slots (6) and the q-axis filling slots (41) are arranged in sequence, and each of the permanent magnet slots (5) and the air slots (6) are arranged in sequence. A connecting rib (8) is provided between the q-axis filling slot (41) and the adjacent air slot (6), and a connecting rib (8) is provided between at least part of the air slot (6) and the permanent magnet slot (5). The q-axis filling slot (41), the air slot (6) and the permanent magnet slot (5) located in the same layer form a layer of magnetic flux barriers. The multiple layers of magnetic flux barriers are arranged at intervals along the d-axis direction. The number of connecting ribs (8) of the magnetic flux barriers located radially outward along the d-axis direction is greater than the number of connecting ribs (8) of the magnetic flux barriers located in other layers.

2. The rotor structure according to claim 1, characterized in that: Each of the magnetic flux barriers is provided with the connecting rib (8) on the d-axis. In the magnetic flux barrier located radially outward along the d-axis direction, the connecting rib (8) is provided between the permanent magnet slot (5) and the air slot (6). In the magnetic flux barriers located in other layers, the permanent magnet slot (5) is connected to the air slot (6).

3. The rotor structure according to claim 2, characterized in that: In the magnetic flux barrier located radially outermost along the d-axis direction, the width of the connecting rib (8) between the permanent magnet slot (5) and the air slot (6) and the width of the connecting rib (8) located on the d-axis are w5, the thickness of the permanent magnet (7) located in the permanent magnet slot (5) is w1, and 0.2*w1≤w5≤0.5*w1.

4. The rotor structure according to claim 1, characterized in that: The thickness of the permanent magnet (7) located radially outermost along the d-axis direction is w1, the thickness of the permanent magnet (7) located radially innermost is w3, and the thickness of the permanent magnet (7) located in the middle layer is w2, w1>w2≥w3.

5. The rotor structure according to claim 4, characterized in that: w1≥1.2*w2.

6. The rotor structure according to claim 1, characterized in that: The permanent magnet slots (5) of different layers located on the same side of the d-axis are parallel to each other, each layer of the magnetic flux barrier includes two rectangular permanent magnets (7), and the two permanent magnets (7) located in the same layer are symmetrical about the d-axis.

7. The rotor structure according to claim 1, characterized in that: Each layer of the magnetic flux barrier comprises two permanent magnets (7); under the same pole, in a cross section perpendicular to the central axis of the rotor core (2), the angle formed by the line connecting the endpoints of the circumferential outer edges of the two permanent magnets (7) located in the same layer and the center of the rotor core (2) is a pole arc angle β, and the pole arc angle β formed by the permanent magnets (7) in each layer is less than 90°.

8. The rotor structure according to claim 7, characterized in that: 40°≤β≤75°; and / or, in the radial direction from the inside to the outside on the d-axis, the pole arc angle β formed by each layer of the permanent magnets (7) decreases.

9. The rotor structure according to claim 1, characterized in that: The permanent magnet slots (5) are rectangular slots, the permanent magnet slots (5) in the same layer of the magnetic flux barrier are symmetrical about the d axis, and the angle between two permanent magnet slots (5) symmetrical about the d axis is α, 140°≤α≤180°.

10. The rotor structure according to claim 9, characterized in that: 150°≤α≤170°。 11. The rotor structure according to claim 1, characterized in that: The width of the magnetic conductive channels between the permanent magnets (7) in adjacent layers on the same side of the q-axis is k1, and the width of the magnetic conductive channels between adjacent q-axis filling slots (41) is k2, where k2>k1.

12. The rotor structure according to claim 11, characterized in that: The minimum width between the permanent magnet slots (5) of different layers is kmin, the width of the permanent magnets (7) of the corresponding layers is wd, and kmin>1.8*wd.

13. The rotor structure according to claim 1, characterized in that: The minimum diameter of the distribution circle of the q-axis filling groove (41) is D1, and the minimum diameter of the distribution circle of the d-axis filling groove (42) is D2, where D2≥D1.

14. The rotor structure according to claim 1, characterized in that The outer diameter of the rotor core (2) is D, the minimum diameter of the distribution circle of the d-axis filling slot (42) is D2, and 0.8D≤D2≤0.9D.

15. The rotor structure according to claim 1, characterized in that The minimum distance between adjacent d-axis filling grooves (42) is w4, the thickness of the permanent magnet (7) located radially outward along the d-axis direction is w1, and w4≥w1.

16. The rotor structure according to claim 1, characterized in that The thickness of the air slot (6) at one end close to the permanent magnet slot (5) is L11, and the thickness of the air slot (6) at one end close to the q-axis filling slot (41) is L12, where L12≥L11.

17. The rotor structure according to claim 1, characterized in that The magnetic flux barrier is three-layered. In a cross section perpendicular to the central axis of the rotor core (2), both ends of the magnetic flux barrier are parallel to the q-axis. The middle of the magnetic flux barrier protrudes toward the outer circle of the rotor core (2). The angle formed by the line connecting the outer ends of the q-axis filling slots (41) at both ends of the magnetic flux barrier located at the radially outermost sides along the d-axis direction and the center of the rotor core (2) is γ, and γ is ≥90°.

18. The rotor structure according to claim 17, characterized in that: 90°≤γ≤120°.

19. The rotor structure according to claim 1, characterized in that The rotor core (2) is provided with a rivet hole (9), and baffles (10) and end rings (11) are provided at both ends of the rotor core (2). The filling groove (4) is filled with a conductive non-magnetic material, and the conductive non-magnetic material is short-circuited through the end ring (11) to form a rotor cage. The baffles (10) are fixedly connected by rivets provided in the rivet holes (9); and / or the permanent magnet slots (5) are filled with resin.

20. An electric motor comprising a stator structure and a rotor structure (1), characterized in that: The rotor structure (1) is the rotor structure according to any one of claims 1 to 19, and the stator structure is sleeved on the outer peripheral side of the rotor structure (1).

21. The motor according to claim 20, characterized in that In a cross section perpendicular to the central axis of the rotor core (2), the width of the connecting rib (8) between the q-axis filling slot (41) and the outer circle of the rotor core (2) is w6, the width of the air gap between the stator structure and the rotor structure (1) is δ, 0≤w6≤2δ, and the width of the connecting rib (8) between the q-axis filling slot (41) and the air slot (6) is w7, 0≤w7≤2δ.

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