Rotor Structure and Permanent Magnet Assisted Synchronous Reluctance Motor

Abstract

The present invention provides a rotor structure and a permanent magnet assisted synchronous reluctance motor. The rotor structure includes a body, a ferrite permanent magnet and a magnetic tuning permanent magnet. The body has a slot group, and a plurality of mounting slots of the slot group are arranged at intervals along the radial direction of the body. A ferrite permanent magnet is arranged in the middle of each mounting slot. Both ends of at least one mounting slot of the plurality of mounting slots in the slot group are provided with a magnetic tuning permanent magnet. The magnetic tuning permanent magnet and the ferrite permanent magnet have the same magnetization direction, the remanence of the magnetic tuning permanent magnet is different from the remanence of the ferrite permanent magnet, and the coercive force of the magnetic tuning permanent magnet is different from the coercive force of the ferrite permanent magnet. The remanence of the ferrite permanent magnet is Br, and the magnetization length is Hm. The remanence of the magnetic tuning permanent magnet is Btr, and the coercive force is Htc. Wherein, 0.6BrHm / Btr≤Htc≤1.35BrHm / Btr. In this way, the ferrite permanent magnet and the magnetic tuning permanent magnet in the mounting slot are placed adjacent to each other and have the same magnetization direction. Moreover, the above parameter restrictions can alleviate the irreversible demagnetization problem of the part close to the outer edge of the main body, and have a good anti-demagnetization effect.

Description

Technical Field

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

[0002] Existing permanent magnet-assisted synchronous reluctance motors utilize a multi-layered magnetic barrier structure with corresponding permanent magnets embedded within it to increase torque density and achieve high efficiency. However, due to the low coercivity of ferrite permanent magnets, they are prone to irreversible demagnetization of the permanent magnets under extreme operating conditions such as high current and low temperatures, resulting in reduced motor efficiency and reliability. Summary of the Invention

[0003] The present invention provides a rotor structure and a permanent magnet assisted synchronous reluctance motor to improve the anti-demagnetization capability of permanent magnets.

[0004] In order to achieve the above-mentioned object, according to one aspect of the present invention, the present invention provides a rotor structure, comprising: a body, the body having a slot group, the slot group including a plurality of mounting slots, the plurality of mounting slots being arranged at intervals along the radial direction of the body, both ends of the mounting slots extending toward the outer edge of the body, and the middle of the mounting slot protruding toward the axial hole of the body; a ferrite permanent magnet, the middle of each mounting slot being provided with the ferrite permanent magnet; a magnetic tuning permanent magnet, the plurality of mounting slots of the slot group being provided with a magnetic tuning permanent magnet. The magnetization-adjusting permanent magnet is provided at both ends of at least one mounting slot, the magnetization direction of the magnetization-adjusting permanent magnet is the same as that of the ferrite permanent magnet, the remanence of the magnetization-adjusting permanent magnet is different from that of the ferrite permanent magnet, and the coercive force of the magnetization-adjusting permanent magnet is different from that of the ferrite permanent magnet; the remanence of the ferrite permanent magnet is Br, and the magnetization length is Hm; the remanence of the magnetization-adjusting permanent magnet is Btr, and the coercive force is Htc; wherein 0.6BrHm / Btr≤Htc≤1.35BrHm / Btr.

[0005] Furthermore, the multiple mounting grooves include a first mounting groove, the first mounting groove includes a first groove and a second groove respectively arranged at both ends of the first groove, and the two ends of the first groove have a first edge line on the side facing away from each other; the ferrite permanent magnet is arranged in the first groove, and the magnetic adjustment permanent magnet is arranged in the second groove, the magnetic adjustment permanent magnet and the ferrite permanent magnet are respectively located on both sides of the first edge line, and the magnetic adjustment permanent magnet and the ferrite permanent magnet in the first mounting groove satisfy the following relationship: 1.2BrHm / Btr≤Htc≤1.35BrHm / Btr.

[0006] Furthermore, the plurality of mounting grooves include a second mounting groove, the second mounting groove includes a third groove and a fourth groove respectively arranged at both ends of the third groove, and the two ends of the third groove have a second edge line on the side facing away from each other; the ferrite permanent magnet is arranged in the third groove, and the magnetization permanent magnet is arranged in the fourth groove, and the magnetization permanent magnet and the ferrite permanent magnet are both located on the same side of the second edge line, and the magnetization permanent magnet and the ferrite permanent magnet in the second mounting groove satisfy the following relationship: 0.6BrHm / Btr≤Htc≤0.75BrHm / Btr.

[0007] Further, the plurality of mounting grooves include a first mounting groove, the first mounting groove includes a first groove and a second groove respectively arranged at both ends of the first groove, and the two ends of the first groove have a first edge line on the side facing away from each other; the ferrite permanent magnet is arranged in the first groove, the magnetic adjustment permanent magnet is arranged in the second groove, and the magnetic adjustment permanent magnet and the ferrite permanent magnet are respectively located on both sides of the first edge line; the plurality of mounting grooves include a second mounting groove, the second mounting groove includes a third groove and a fourth groove respectively arranged at both ends of the third groove, and the two ends of the third groove have a second edge line on the side facing away from each other; the ferrite permanent magnet is arranged in the third groove, the magnetic adjustment permanent magnet is arranged in the fourth groove, and the magnetic adjustment permanent magnet and the ferrite permanent magnet are both located on the same side of the second edge line; in the slot group, the mounting groove closest to the shaft hole is the first mounting groove, and the other mounting grooves are all the second mounting grooves.

[0008] Furthermore, the ferrite permanent magnet includes a first permanent magnet and a second permanent magnet respectively arranged at both ends of the first permanent magnet, and there is an angle between the second permanent magnet and the first permanent magnet; in the mounting groove, the first permanent magnet, the second permanent magnet and the magnetic adjustment permanent magnet are arranged in sequence away from the axial hole of the body.

[0009] Furthermore, the length of the second permanent magnet is Lm, the length of the magnetization permanent magnet is Ltm, and 0.5Lm≤Ltm.

[0010] Furthermore, the magnetization permanent magnet and the second permanent magnet in the installation slot extend in the same direction; in the first installation slot, the length of the overlapping portion of the magnetization permanent magnet and the second permanent magnet in the extension direction is Lt, and Lt≤1 / 3Ltm.

[0011] Furthermore, the ferrite permanent magnet is an integrally formed arc-shaped structure, and the ferrite permanent magnet and the magnetic-tuning permanent magnet have the same width at the ends close to each other.

[0012] Furthermore, the slot group has a magnetic pole center line passing through the center of the body, the installation slot is divided into two symmetrical parts by the magnetic pole center line, and the two magnetic-tuning permanent magnets in the installation slot are symmetrically arranged relative to the magnetic pole center line.

[0013] Furthermore, the magnetic-tuning permanent magnet is a sintered samarium-cobalt permanent magnet or a bonded neodymium-iron-boron permanent magnet.

[0014] Furthermore, Br<Btr.

[0015] Furthermore, the main body has a plurality of groove groups, and the plurality of groove groups are distributed in a one-to-one correspondence on a plurality of fan-shaped areas of the main body, and the arc of each fan-shaped area is a minor arc.

[0016] According to another aspect of the present invention, a permanent magnet assisted synchronous reluctance motor is provided. The permanent magnet assisted synchronous reluctance motor includes the above-mentioned rotor structure.

[0017] The technical solution of the present invention is applied to provide a rotor structure, which includes a body, a ferrite permanent magnet and a magnetization-tuning permanent magnet. The body has a slot group, which includes a plurality of mounting slots, which are arranged at intervals along the radial direction of the body, with both ends of the mounting slots extending toward the outer edge of the body and the middle of the mounting slot protruding toward the axial hole of the body; a ferrite permanent magnet is arranged in the middle of each mounting slot; a magnetization-tuning permanent magnet is arranged at both ends of at least one mounting slot in the plurality of mounting slots in the slot group, the magnetization-tuning permanent magnet and the ferrite permanent magnet having the same magnetization direction, the remanence of the magnetization-tuning permanent magnet being different from the remanence of the ferrite permanent magnet, and the coercive force of the magnetization-tuning permanent magnet being different from the coercive force of the ferrite permanent magnet; the remanence of the ferrite permanent magnet is Br, and the magnetization length is Hm; the remanence of the magnetization-tuning permanent magnet is Btr, and the coercive force is Htc; wherein 0.6BrHm / Btr≤Htc≤1.35BrHm / Btr. With this solution, the ferrite permanent magnet and the magnetic tuning permanent magnet in the mounting slot are placed adjacent to each other and have the same magnetization direction. Moreover, through the above parameter restrictions, the irreversible demagnetization problem of the part close to the outer edge of the main body can be alleviated, and a good anti-demagnetization effect can be achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The accompanying drawings, which constitute part of this application, are intended to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are intended to explain the present invention and do not constitute an undue limitation of the present invention. In the accompanying drawings:

[0019] Figure 1 A schematic diagram of a rotor structure provided by embodiment 1 of the present invention is shown;

[0020] Figure 2 Shown Figure 1 A partial enlarged view of

[0021] Figure 3 A schematic diagram of a rotor structure provided by a second embodiment of the present invention is shown;

[0022] Figure 4 Shown Figure 3 A partial enlarged view of

[0023] Figure 5 A schematic diagram of a rotor structure provided by a third embodiment of the present invention is shown;

[0024] Figure 6 The figure shows the magnetic field cloud diagram of the motor in the prior art;

[0025] Figure 7 The figure shows the magnetic field contour of a motor using the technology in this application.

[0026] The above drawings include the following reference numerals:

[0027] 10. Main body; 11. First mounting slot; 12. Second mounting slot; 20. Ferrite permanent magnet; 21. First permanent magnet; 22. Second permanent magnet; 30. Magnetization permanent magnet. DETAILED DESCRIPTION

[0028] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the embodiments described are only some embodiments of the present invention, not all 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. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative work are within the scope of protection of the present invention.

[0029] As shown in the accompanying drawings, an embodiment of the present invention provides a rotor structure, comprising: a body 10, the body 10 having a slot group, the slot group including a plurality of mounting slots, the plurality of mounting slots being arranged at intervals along the radial direction of the body 10, both ends of the mounting slots extending toward the outer edge of the body 10, and the middle of the mounting slot protruding toward the axial hole of the body 10; a ferrite permanent magnet 20, the middle of each mounting slot being provided with a ferrite permanent magnet 20; a magnetic tuning permanent magnet 30, at least one of the plurality of mounting slots in the slot group having a plurality of mounting slots disposed therein; A magnetization-adjusting permanent magnet 30 is provided at both ends. The magnetization direction of the magnetization-adjusting permanent magnet 30 is the same as that of the ferrite permanent magnet 20. The remanence of the magnetization-adjusting permanent magnet 30 is different from that of the ferrite permanent magnet 20, and the coercive force of the magnetization-adjusting permanent magnet 30 is different from that of the ferrite permanent magnet 20. The remanence of the ferrite permanent magnet 20 is Br, and the magnetization length is Hm. The remanence of the magnetization-adjusting permanent magnet 30 is Btr, and the coercive force is Htc. Among them, 0.6BrHm / Btr≤Htc≤1.35BrHm / Btr.

[0030] The technical solution of the present invention is applied to provide a rotor structure, which includes a body 10, a ferrite permanent magnet 20 and a magnetic tuning permanent magnet 30. The body 10 has a slot group, which includes a plurality of mounting slots. The plurality of mounting slots are arranged at intervals along the radial direction of the body 10, with both ends of the mounting slot extending toward the outer edge of the body 10, and the middle of the mounting slot protruding toward the axial hole of the body 10; a ferrite permanent magnet 20 is arranged in the middle of each mounting slot; at least one mounting slot of the plurality of mounting slots in the slot group is provided with a ferrite permanent magnet 20; A magnetic-tuning permanent magnet 30 is provided at both ends of the body 10. The magnetic-tuning permanent magnet 30 and the ferrite permanent magnet 20 have the same magnetization direction, but the remanence of the magnetic-tuning permanent magnet 30 is different from that of the ferrite permanent magnet 20, and the coercive force of the magnetic-tuning permanent magnet 30 is different from that of the ferrite permanent magnet 20. The remanence of the ferrite permanent magnet 20 is Br, and the magnetization length is Hm. The remanence of the magnetic-tuning permanent magnet 30 is Btr, and the coercive force is Htc. Wherein, 0.6BrHm / Btr≤Htc≤1.35BrHm / Btr. With this solution, the ferrite permanent magnet and the magnetic-tuning permanent magnet 30 in the mounting slot are placed adjacent to each other and have the same magnetization direction. Moreover, through the above-mentioned parameter restrictions, the problem of irreversible demagnetization of the portion near the outer edge of the body 10 can be alleviated, and good anti-demagnetization effect can be achieved.

[0031] like Figure 1 and Figure 2 As shown, the multiple mounting slots include a first mounting slot 11, which includes a first groove and second grooves disposed at either end of the first groove. The first groove's opposite ends each have a first edge line. A ferrite permanent magnet 20 is disposed in the first groove, and a magnetization permanent magnet 30 is disposed in the second groove. The magnetization permanent magnet 30 and the ferrite permanent magnet 20 are located on either side of the first edge line. The magnetization permanent magnet 30 and the ferrite permanent magnet 20 in the first mounting slot 11 satisfy the following relationship: 1.2BrHm / Btr≤Htc≤1.35BrHm / Btr. This arrangement can further improve the rotor structure's anti-demagnetization performance.

[0032] In this embodiment, the multiple mounting slots further include a second mounting slot 12, which includes a third slot and fourth slots disposed at either end of the third slot. The third slot has a second edgeline on both sides facing away from each other. A ferrite permanent magnet 20 is disposed in the third slot, and a magnetization permanent magnet 30 is disposed in the fourth slot. The magnetization permanent magnet 30 and the ferrite permanent magnet 20 are both located on the same side of the second edgeline. The magnetization permanent magnet 30 and the ferrite permanent magnet 20 in the second mounting slot 12 satisfy the following relationship: 0.6BrHm / Btr≤Htc≤0.75BrHm / Btr. This arrangement can further improve the anti-demagnetization performance of the rotor structure. Specifically, the first edgeline and the second edgeline are disposed in parallel.

[0033] In this embodiment, the mounting slot closest to the shaft hole in the slot group is the first mounting slot 11, and all other mounting slots are second mounting slots 12. This effectively increases the demagnetization resistance of the innermost permanent magnets, where demagnetization occurs most, and effectively utilizes rotor space. In this embodiment, the magnetization length of the field-tuning permanent magnets 30 is Htm.

[0034] Furthermore, the ferrite permanent magnet 20 includes a first permanent magnet 21 and a second permanent magnet 22 respectively arranged at both ends of the first permanent magnet 21, and there is an angle between the second permanent magnet 22 and the first permanent magnet 21; in the installation groove, the first permanent magnet 21, the second permanent magnet 22 and the magnetic adjustment permanent magnet 30 are arranged in sequence away from the axial hole of the main body 10.

[0035] In this embodiment, the length of the second permanent magnet 22 is Lm, the length of the magnetization permanent magnet 30 is Ltm, and 0.5Lm≤Ltm. This can fully utilize the adjustment characteristics of the magnetization permanent magnet and effectively reduce the demagnetization effect.

[0036] In this embodiment, the magnetization-adjusting permanent magnet 30 and the second permanent magnet 22 in the installation slot extend in the same direction; in the first installation slot 11, the length of the overlapping portion of the magnetization-adjusting permanent magnet 30 and the second permanent magnet 22 in the extension direction is Lt, and Lt≤1 / 3Ltm.

[0037] In other embodiments, the ferrite permanent magnet 20 may be configured as an integrally formed arc-shaped structure, and the widths of the ferrite permanent magnet 20 and the magnetization permanent magnet 30 at the ends adjacent to each other are equal.

[0038] In the above embodiment, the slot group has a magnetic pole centerline passing through the center of the body 10, and the installation slot is divided into two symmetrical parts by the magnetic pole centerline. The two magnetic tuning permanent magnets 30 in the installation slot are symmetrically arranged relative to the magnetic pole centerline.

[0039] In the above embodiment, the magnetic-tuning permanent magnet 30 is a sintered samarium-cobalt permanent magnet or a bonded neodymium-iron-boron permanent magnet, which can significantly improve the demagnetization problem of the motor.

[0040] In the above embodiment, Br<Btr, which can maintain the high efficiency of the rotor structure and the motor.

[0041] In the above embodiment, the main body 10 has a plurality of groove groups, and the plurality of groove groups are distributed in a one-to-one correspondence on a plurality of sector-shaped areas of the main body 10 , and the arc of each sector-shaped area is a minor arc.

[0042] Furthermore, the magnetization-tuning permanent magnets placed at both ends of the mounting slot can improve the demagnetization resistance of the permanent magnets, and therefore the motor, by adjusting their thickness in the magnetization direction and their coercive force. To effectively utilize the magnetization-tuning permanent magnets, their thickness can be reduced when their coercive force is high, and increased when their coercive force is low.

[0043] Furthermore, when the thickness or coercive force of the magnetic-tuning permanent magnet is set too large, the demagnetization area of the magnetic-tuning permanent magnet is reduced, but it will affect the demagnetization of the ferrite permanent magnet, increase the demagnetization area of the ferrite permanent magnet, increase the overall demagnetization area of the motor, and make the irreversible demagnetization of the motor more serious; when the thickness and coercive force are set too small, under a certain current, the demagnetization area of the magnetic-tuning permanent magnet increases, which fails to achieve the purpose of regulating the demagnetization of the motor.

[0044] Therefore, the remanence and coercive force of the ferrite permanent magnet are assumed to be Br and Hc respectively, the magnetization length of the adjacent part is assumed to be Hm, the remanence and coercive force of the magnetic tuning permanent magnet are assumed to be Btr and Htc respectively, and when the edge line of the mounting slot corresponding to the magnetic tuning permanent magnet is located below the edge line corresponding to the ferrite permanent magnet, 1.2BrHm / Btr≤Htc≤1.35BrHm / Btr is satisfied; when the edge line of the mounting slot corresponding to the magnetic tuning permanent magnet is located above the edge line corresponding to the ferrite permanent magnet, 0.6BrHm / Btr≤Htc≤0.75BrHm / Btr is satisfied, and the motor has a good anti-demagnetization effect.

[0045] The permanent magnets embedded in the multi-layer mounting grooves are more easily demagnetized at the two ends of the mounting grooves than at other positions. Therefore, the magnetization-adjusting permanent magnets are located at positions corresponding to the two ends of the mounting grooves.

[0046] Furthermore, the position of the magnetic tuning permanent magnet can be located in the same line with the two ends of the ferrite permanent magnet, or it can be located above the two ends of the ferrite permanent magnet, or it can be located below the two ends of the ferrite permanent magnet. Any position where one side is adjacent to any side of the ferrite can increase the anti-demagnetization ability of the corresponding permanent magnets at the two ends of the mounting slot.

[0047] Furthermore, in order to reduce the number of assembly steps and simplify the amount of permanent magnets used, corresponding permanent magnets in multiple layers of mounting grooves include at least one layer of mounting grooves containing the two types of permanent magnets.

[0048] Furthermore, in the permanent magnet-assisted synchronous permanent magnet-assisted synchronous reluctance motor with a multi-layer mounting slot structure, the permanent magnets in the innermost mounting slot close to the center of the rotor are more prone to local demagnetization than the permanent magnets in other layers. Therefore, the magnetic adjustment permanent magnets are located at both ends of the innermost mounting slot, which can show better results.

[0049] Furthermore, in order to avoid saturation of the quadrature axis magnetic circuit and reserve sufficient width for the quadrature axis, the phase distance between the two ends of the installation slot should maintain a certain width. Therefore, when the magnetic adjustment permanent magnet is located above the ferrite permanent magnet, the length of the overlapping part of the two does not exceed 1 / 3 of the length of the magnetic adjustment permanent magnet; when the magnetic adjustment permanent magnet is located below the ferrite permanent magnet, the edge line of the magnetic adjustment permanent magnet is aligned with the edge line of the two end parts of the ferrite permanent magnet along the center direction of the rotor.

[0050] Furthermore, when the debugging permanent magnet and the ferrite permanent magnet do not overlap, the magnetic adjustment characteristics of the magnetic adjustment permanent magnet can be maximized.

[0051] Furthermore, to meet process requirements and reduce the difficulty of producing the permanent magnet, the width of the magnetization permanent magnet is kept roughly equal to that of the innermost ferrite permanent magnet. By adjusting the coercive force of the permanent magnet, the demagnetization resistance is improved. Meeting the requirement of Btr = 1.26BrHm can further improve the demagnetization resistance of the permanent magnet.

[0052] Furthermore, the number of mounting groove layers is a positive integer, and the shape formed can be V-shaped, U-shaped, C-shaped, etc. Any shape in which the angle between the edge lines of the two end portions of the mounting groove along the center of the rotor is less than 180 degrees can be improved by the technology of this application, that is, by setting a magnetically adjustable permanent magnet to improve the anti-demagnetization ability of the motor.

[0053] Another embodiment of the present invention provides a permanent magnet-assisted synchronous reluctance motor, comprising the aforementioned rotor structure. A motor and device utilizing the technology of this solution can effectively mitigate the vulnerability of ferrite permanent magnets to demagnetization, thereby improving motor reliability and efficiency.

[0054] In the prior art, permanent magnet-assisted synchronous reluctance motors with multiple mounting slots are often prone to permanent magnet demagnetization near the rotor's outer diameter. In this application, the permanent magnets in the mounting slots are ferrite permanent magnets and field-tuning permanent magnets, placed adjacently with the same magnetization direction, which can alleviate the problem of irreversible demagnetization near the rotor's outer diameter.

[0055] exist Figure 6 and Figure 7 The color depth in the long box in the upper left corner represents the demagnetization flux density of the permanent magnet. Darker colors indicate more severe demagnetization, and pure black indicates zero demagnetization. It is obvious that the flux density at the ends of the multi-layer permanent magnet is lower, and the innermost layer of the permanent magnet has the lowest flux density, indicating that these two parts are most susceptible to demagnetization. Figure 6 The permanent magnets at the end are magnetized in the reverse direction (severe demagnetization will cause directional magnetization), and the permanent magnets near the center are demagnetized to zero. Figure 7 The two corresponding parts are demagnetized to zero. Figure 6 The permanent magnets at both ends will not be able to return to the initial magnetic field state, and irreversible demagnetization will occur. Figure 7 The permanent magnets at both ends can be restored to their initial magnetic field state without irreversible demagnetization. That is, the technology in this application can greatly reduce the degree of demagnetization and improve the demagnetization resistance of the permanent magnet.

[0056] Permanent magnet-assisted synchronous reluctance motors use multiple layers of mounting slots and embedded ferrite permanent magnets to increase reluctance torque, thereby improving output torque and increasing motor efficiency. However, under harsh operating conditions such as high currents, irreversible demagnetization of ferrite permanent magnets is a common problem. Demagnetization occurs at both ends of the ferrite permanent magnets in the multiple layers of mounting slots, and the demagnetization area of the innermost layer of permanent magnets is larger than that of the other layers of permanent magnets. This solution utilizes hybrid permanent magnets, adding some magnetizing permanent magnets with different parameters than the original permanent magnets to the area prone to demagnetization. This can reduce the demagnetization area of the permanent magnets in the mounting slots, increase the motor's anti-demagnetization capability, and increase motor efficiency. Figure 6 and Figure 7 The demagnetization current of the structure is shown in the table below. Taking the demagnetization rate of 3% as the standard, it can be clearly seen that after adopting this technical solution, the demagnetization current of the motor is increased from 45A to 55A, and the anti-demagnetization ability is improved by 22%, which greatly improves the demagnetization problem.

[0057]

[0058] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of protection of the present invention.

Claims

1. A rotor structure, characterized in that: include: A body (10), the body (10) having a slot group, the slot group including a plurality of mounting slots, the plurality of mounting slots being arranged at intervals along the radial direction of the body (10), both ends of the mounting slots extending toward the outer edge of the body (10), and the middle portion of the mounting slot protruding toward the axial hole of the body (10); A ferrite permanent magnet (20), wherein the middle portion of each mounting slot is provided with the ferrite permanent magnet (20); A magnetization-adjusting permanent magnet (30), wherein both ends of at least one of the plurality of mounting slots in the slot group are provided with the magnetization-adjusting permanent magnet (30), the magnetization direction of the magnetization-adjusting permanent magnet (30) and the ferrite permanent magnet (20) are the same, the remanence of the magnetization-adjusting permanent magnet (30) is different from the remanence of the ferrite permanent magnet (20), and the coercive force of the magnetization-adjusting permanent magnet (30) is different from the coercive force of the ferrite permanent magnet (20); The remanence of the ferrite permanent magnet (20) is Br, and the magnetization length is Hm; the remanence of the magnetic-adjusting permanent magnet (30) is Btr, and the coercive force is Htc; The plurality of mounting grooves include a first mounting groove (11) and a second mounting groove (12), the first mounting groove (11) including a first groove and a second groove respectively arranged at two ends of the first groove, the two ends of the first groove having a first edge line on one side facing away from each other; a first type of ferrite permanent magnet is arranged in the first groove, a first type of magnetism-adjusting permanent magnet is arranged in the second groove, the first type of magnetism-adjusting permanent magnet and the first type of ferrite permanent magnet are respectively located on both sides of the first edge line, and the first type of magnetism-adjusting permanent magnet and the first type of ferrite permanent magnet in the first mounting groove (11) satisfy the following relationship: 1.2BrHm / Btr≤Htc≤1.35BrHm / Btr; The second mounting groove (12) comprises a third groove and fourth grooves respectively arranged at both ends of the third groove, and the two ends of the third groove have a second side line on the side facing away from each other; a second type of ferrite permanent magnet is arranged in the third groove, and a second type of magnetism-adjusting permanent magnet is arranged in the fourth groove, and the second type of magnetism-adjusting permanent magnet and the second type of ferrite permanent magnet are both located on the same side of the second side line, and the second type of magnetism-adjusting permanent magnet and the second type of ferrite permanent magnet in the second mounting groove (12) satisfy the following relationship: 0.6BrHm / Btr≤Htc≤0.75BrHm / Btr.

2. The rotor structure according to claim 1, characterized in that: In the slot group, the mounting slot closest to the shaft hole is the first mounting slot (11), and the other mounting slots are all the second mounting slots (12).

3. The rotor structure according to claim 1, characterized in that: The ferrite permanent magnet (20) comprises a first permanent magnet (21) and a second permanent magnet (22) respectively arranged at both ends of the first permanent magnet (21), and an angle is formed between the second permanent magnet (22) and the first permanent magnet (21); in the mounting groove, the first permanent magnet (21), the second permanent magnet (22) and the magnetic adjustment permanent magnet (30) are sequentially arranged away from the axial hole of the body (10).

4. The rotor structure according to claim 3, characterized in that: The length of the second permanent magnet (22) is Lm, the length of the magnetization permanent magnet (30) is Ltm, and 0.5Lm≤Ltm.

5. The rotor structure according to claim 3, characterized in that: The magnetization-adjusting permanent magnet (30) and the second permanent magnet (22) in the installation slot extend in the same direction; in the first installation slot (11), the length of the overlapping portion of the magnetization-adjusting permanent magnet (30) and the second permanent magnet (22) in the extension direction is Lt, and Lt≤1 / 3Ltm.

6. The rotor structure according to claim 1, characterized in that: The ferrite permanent magnet (20) is an integrally formed arc-shaped structure, and the ferrite permanent magnet (20) and the magnetic adjustment permanent magnet (30) have the same width at the ends close to each other.

7. The rotor structure according to claim 1, characterized in that: The slot group has a magnetic pole center line passing through the center of the body (10), the installation slot is divided into two symmetrical parts by the magnetic pole center line, and the two magnetic adjustment permanent magnets (30) in the installation slot are symmetrically arranged relative to the magnetic pole center line.

8. The rotor structure according to claim 1, characterized in that: The magnetic adjustment permanent magnet (30) is a sintered samarium cobalt permanent magnet or a bonded neodymium iron boron permanent magnet.

9. The rotor structure according to claim 1, characterized in that: Br<Btr.

10. The rotor structure according to claim 1, characterized in that: The body (10) has a plurality of groove groups, and the plurality of groove groups are distributed one-to-one on a plurality of fan-shaped areas of the body (10), and the arc of each fan-shaped area is a minor arc.

11. A permanent magnet assisted synchronous reluctance motor, characterized in that: The permanent magnet assisted synchronous reluctance motor comprises the rotor structure according to any one of claims 1 to 10.

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