Built-in asymmetric magnetic pole permanent magnet rotor and motor

Abstract

The application discloses an inner asymmetric magnetic pole permanent magnet rotor and motor, comprising a rotor core, the rotor core comprises a plurality of magnetic barrier structures arranged in the circumferential direction, each magnetic barrier structure comprises a front edge magnetic steel on the side of the front edge of the magnetic barrier structure along the rotation direction of the rotor core and a rear edge magnetic steel on the side of the rear edge of the magnetic barrier structure along the rotation direction of the rotor core, the residual magnetism of the front edge magnetic steel of each magnetic barrier structure is less than that of the rear edge magnetic steel, and the coercive force of the front edge magnetic steel of each magnetic barrier structure is less than that of the rear edge magnetic steel. The application can reduce the saturation of the magnetic circuit of the front edge of the rotor, reduce the leakage magnetic flux outside the rotor, improve the output torque of the motor and the efficiency of the motor, increase the coercive force of the rear edge magnetic pole magnetic steel of the rotor, improve the anti-demagnetization capability, and improve the reliability and efficiency of the motor under high speed and heavy load.

Description

Technical Field

[0001] This invention relates to the field of motor equipment technology, and in particular to a built-in asymmetric permanent magnet rotor and motor. Background Technology

[0002] Permanent magnet motors (PMMs) generate their magnetic field using permanent magnets, eliminating the need for excitation coils and excitation current. This results in a simple structure, high power density, and high efficiency. With the advent of high-performance permanent magnet materials and the rapid development of control technology, the applications of PMMs will become more widespread. While permanent magnets offer performance advantages at low speeds, the back electromotive force increases significantly with motor speed, necessitating field weakening control. This involves diverting some current from the windings to weaken the permanent magnet's magnetic field, ultimately leading to demagnetization of the permanent magnets and lower motor efficiency at high speeds. Furthermore, to increase the power density of PMMs, a large amount of permanent magnets is used, and high-performance permanent magnets are expensive, accounting for approximately 20% of the motor cost. Improving the speed-up and demagnetization resistance of PMMs while reducing their cost are current research priorities.

[0003] In a permanent magnet motor, the magnetic field generated by the poles is called the main pole magnetic field, and the magnetic field generated by the stator windings is called the armature magnetic field. During motor operation, the armature magnetic field distorts the main magnetic field, strengthening the magnetic field on one side of the pole and weakening it on the other side; this is called armature reaction. The greater the load, the stronger the magnetic field distortion caused by armature reaction. Armature reaction leads to increased magnetization of the poles at the leading edge of rotation and decreased magnetization of the poles at the trailing edge. Current permanent magnet motors have identical magnetic barrier structures and properties per pole. If the remanence is high, the magnetic circuit at the leading edge of the rotor will be severely saturated, resulting in leakage flux on the outer circumference of the rotor and reduced motor efficiency. If the coercivity of the magnets is too low, the magnets at the trailing edge have weak resistance to demagnetization, making them prone to demagnetization under high speed and heavy load. Summary of the Invention

[0004] In order to overcome the above-mentioned shortcomings of the prior art, the purpose of this invention is to propose a built-in asymmetric magnetic pole permanent magnet rotor and motor to solve the problems mentioned in the background art.

[0005] The technical solution adopted by the present invention to solve its technical problem is: a built-in asymmetric magnetic pole rotor, including a rotor core, wherein the rotor core includes a plurality of magnetic barrier structures arranged circumferentially, each magnetic barrier structure including a leading edge magnet on the side where the magnetic barrier structure turns forward along the rotation direction of the rotor core and a trailing edge magnet on the side where the magnetic barrier structure turns backward along the rotation direction of the rotor core, wherein the remanence of the leading edge magnet of each magnetic barrier structure is less than the remanence of the trailing edge magnet.

[0006] An internal asymmetric magnetic pole rotor includes a rotor core, the rotor core including a plurality of magnetic barrier structures arranged circumferentially, each magnetic barrier structure including a leading magnet on the side where the magnetic barrier structure turns forward along the rotation direction of the rotor core and a trailing magnet on the side where the magnetic barrier structure turns backward along the rotation direction of the rotor core, wherein the coercivity of the leading magnet of each magnetic barrier structure is less than the coercivity of the trailing magnet.

[0007] As a further improvement of the present invention: the rotor core further includes a plurality of magnetic poles arranged circumferentially, each magnetic pole being provided with a magnetic barrier structure composed of permanent magnets, and the plurality of magnetic barrier structures being arranged at intervals in a radial direction away from the center of the rotor core.

[0008] As a further improvement of the present invention: each of the magnetic poles is arranged symmetrically about the axis of symmetry D, and the magnetic barrier structure is arranged symmetrically about the axis of symmetry D.

[0009] As a further improvement of the present invention: the magnetic barrier structure is configured with a leading edge magnet on the side where the turning leading edge of the D-axis is located, and the magnetic barrier structure is configured with a trailing edge magnet on the side where the turning trailing edge of the D-axis is located.

[0010] As a further improvement of the present invention: the arrangement of permanent magnets in the magnetic barrier structure includes any one of UV structure, U-shaped structure, V-shaped structure, and V-type structure.

[0011] As a further improvement of the present invention: the permanent magnet is composed of any one of ferrite or neodymium iron boron permanent magnet materials.

[0012] As a further improvement of the present invention: the remanence of the leading magnet of the magnetic barrier structure along the rotation direction of the rotor core is B. r1 The remanence of the trailing edge magnet of the magnetic barrier structure along the direction of rotor core rotation is B. r2 , of which 0.6B r2 ≤B r1 ≤0.8B r2 .

[0013] As a further improvement of the present invention: the coercivity of the leading magnet of the magnetic barrier structure along the rotation direction of the rotor core is H. c1 The coercivity of the trailing edge magnet of the magnetic barrier structure along the direction of rotor core rotation is H. c2 , of which 0.75H c2 ≤H c1 ≤0.9H c2 .

[0014] According to another aspect of this application, a built-in asymmetric magnetic pole permanent magnet motor is provided, including a motor stator wound with copper wire and a motor rotor with built-in permanent magnets. The motor rotor includes the built-in asymmetric magnetic pole rotor as described above. The motor rotor contains a plurality of magnetic barrier structures arranged circumferentially. When the motor rotor rotates, the magnetic flux density inside the motor rotor is uniform.

[0015] Compared with the prior art, the beneficial effects of the present invention are:

[0016] 1. This invention proposes a built-in asymmetric permanent magnet rotor and motor. The motor rotor uses permanent magnets of different grades. The remanent magnetism of the leading edge magnet of each magnetic pole of the rotor is lower than that of the trailing edge magnet. This can reduce magnetic circuit saturation at the leading edge of the rotor, reduce external magnetic leakage, improve motor output torque, and improve motor efficiency. At the same time, it increases the coercivity of the trailing edge magnet, improves the anti-demagnetization ability, and improves the reliability and efficiency of the motor under high speed and heavy load.

[0017] 2. This invention proposes a permanent magnet motor with a built-in asymmetric magnetic pole structure, wherein the remanence B of the leading-edge magnetic steel of each rotor pole is [missing information]. r1 Residual magnetism B along the pole steel after the rotor rotates r2 Small size can reduce rotor front-end magnetic circuit saturation caused by armature reaction, reduce leakage flux, and improve motor efficiency.

[0018] 3. The coercivity H of the leading-edge magnetic pole of the rotor in this invention is... c1 The coercivity H of the magnetic pole magnet along the rotor direction after rotation c2 The small, balanced coercivity design ensures the demagnetization resistance of the rear steering magnet, providing high-speed, heavy-load reliability and motor efficiency. At the same time, it reduces the coercivity of the front steering magnet, ensuring demagnetization resistance while reducing the cost of motor magnets. Attached Figure Description

[0019] Figure 1 A schematic diagram of the armature reaction phenomenon in a permanent magnet motor.

[0020] Figure 2 This is a schematic diagram of the UV-structure magnetic barrier structure motor of the present invention;

[0021] Figure 3 This is a schematic diagram of the U-shaped magnetic barrier structure motor of the present invention;

[0022] Figure 4 This is a schematic diagram of the V-shaped magnetic barrier structure motor of the present invention;

[0023] Figure 5 This is a schematic diagram of the V-type magnetic barrier structure motor of the present invention;

[0024] The numbers in the diagram are: 1. Motor stator, 2. Rotor core, 21. Leading edge magnet, 22. Trailing edge magnet. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below in conjunction with specific embodiments and corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0026] The present invention will now be further described in conjunction with the accompanying drawings and embodiments:

[0027] To facilitate understanding, the following terms are explained:

[0028] The leading edge of the steering wheel: the side in front of the rotor rotation direction when the motor is running;

[0029] Rear edge of rotation: The side behind the rotor rotation direction when the motor is running;

[0030] Armature reaction: During the operation of an electric motor, the armature magnetic field distorts the main magnetic field, strengthening the magnetic field on one side of the pole and weakening the magnetic field on the other side. This is called armature reaction.

[0031] Remanence: The residual magnetic induction intensity of a permanent magnet material after it has been magnetized to saturation in an external magnetic field, when the applied magnetic field is reduced to zero.

[0032] Coercivity: The reverse magnetic field strength required to reduce the remanent magnetic induction intensity to zero when a permanent magnet material is saturated with magnetization by adjusting the strength of the applied magnetic field.

[0033] Figure 1 In the diagram, area A is characterized by magnetic pole magnetization generated by the leading edge of the motor rotor along the direction of rotation, exhibiting saturated magnetic leakage; area B is characterized by magnetic pole demagnetization generated by the trailing edge of the motor rotor along the direction of rotation, exhibiting unsaturated magnetic leakage.

[0034] In a permanent magnet motor, the magnetic field generated by the poles is called the main pole magnetic field, and the magnetic field generated by the stator windings is called the armature magnetic field. During motor operation, the armature magnetic field distorts the main magnetic field, strengthening the magnetic field on one side of the pole and weakening it on the other side; this is called armature reaction. The greater the load, the stronger the magnetic field distortion caused by armature reaction. Armature reaction leads to increased magnetization of the poles at the leading edge of rotation and decreased magnetization of the poles at the trailing edge. Current permanent magnet motors have the same magnetic barrier structure and magnetic properties per pole. If the remanence is high, the magnetic circuit at the leading edge of the rotor will be severely saturated, resulting in leakage flux on the outer circumference of the rotor, leading to reduced motor efficiency. If the coercivity of the magnets is too low, the anti-demagnetization ability of the magnets at the trailing edge 22 is weak, making them prone to demagnetization under high speed and heavy load.

[0035] This invention discloses a built-in asymmetric permanent magnet rotor and motor. The motor rotor uses different grades of permanent magnets. The remanence of the magnets at the leading edge of the rotor's rotation is lower than that at the trailing edge, which reduces magnetic saturation at the leading edge, decreases external magnetic leakage, increases motor output torque, and improves motor efficiency. Simultaneously, it increases the coercivity of the magnets at the trailing edge, enhances demagnetization resistance, and improves the motor's reliability and efficiency under high-speed, heavy-load conditions. Considering actual operating conditions, the selection of different grades of permanent magnets at the leading and trailing edges of the rotor can reduce the overall cost of the motor's permanent magnets and improve the motor's market competitiveness. These differences are explained in detail below.

[0036] Example 1:

[0037] This invention combines the principle of pre-armature reaction magnetization followed by post-armature demagnetization, see reference. Figure 1-4 This invention provides a built-in asymmetric magnetic pole rotor, including a rotor core 2. The rotor core 2 includes multiple magnetic barrier structures arranged circumferentially. Each magnetic barrier structure includes a leading magnet 21 on the side where the magnetic barrier structure's turning leading edge is located along the rotation direction of the rotor core 2, and a trailing magnet 22 on the side where the magnetic barrier structure's turning trailing edge is located along the rotation direction of the rotor core 2. The remanence of the leading magnet 21 in each magnetic barrier structure is less than the remanence of the trailing magnet 22. In this invention, the remanence B of the leading magnet of each magnetic pole of the rotor is... r1 Residual magnetism B along the pole steel after the rotor rotates r2 Small size can reduce rotor front-end magnetic circuit saturation caused by armature reaction, reduce leakage flux, and improve motor efficiency.

[0038] In an optional embodiment, the remanence of the leading magnet 21 of the magnetic barrier structure at the leading edge along the rotation direction of the rotor core 2 is B. r1 The remanence of the trailing edge magnet 22, which is the magnetic barrier structure along the direction of rotation of the rotor core 2, is B. r2 , of which 0.6B r2 ≤B r1 ≤0.8B r2 .

[0039] Taking into account the characteristic that the higher the magnetic induction intensity, the higher the magnetic flux density of the motor, the residual magnetism of the rotor leading edge magnet 21 is designed to be B. r1 After the rotor rotates, the residual magnetism along magnet 22 is B. r2 And satisfying 0.6B r2 ≤B r1 ≤0.8B r2 At this time, the magnetic flux density inside the motor rotor is uniform, leakage flux is reduced, and the output reluctance torque is increased. If 0.6B r2 ≥B r1 The residual magnetism of the leading edge magnet 21 of the rotor is low, resulting in low overall permanent magnet torque output from the motor; if Br1 >0.8B r2 The residual magnetism of the magnet 21 at the rotor's turning edge is relatively high, the magnetic flux density at the rotor's turning edge is high, the leakage flux is serious, the motor's magnetic reluctance torque is reduced, and the overall efficiency is low.

[0040] In this embodiment, the rotor core 2 is used in a motor. The rotor core 2 also includes multiple magnetic poles arranged circumferentially. Each magnetic pole has a magnetic barrier structure composed of permanent magnets. The multiple magnetic barrier structures arranged circumferentially can improve the motor torque, and the multiple magnetic barrier structures are arranged at intervals in the radial direction away from the center of the rotor core 2. By setting multiple magnetic poles on the rotor core 2, and arranging the multiple magnetic barrier structures on the magnetic poles at intervals in the radial direction away from the center of the rotor core 2, the magnetic field stability of the rotor core 2 during rotation can be improved, torque pulsation can be reduced, the saliency ratio of the motor can be increased, and the reluctance torque of the motor can be improved. At the same time, the magnetic barrier structure is composed of permanent magnets, and the permanent magnet magnetic barrier structure provides direct-axis permanent magnet flux to the motor, increasing the torque density and permanent magnet torque of the motor.

[0041] In this embodiment, each magnetic pole is symmetrically arranged about the axis of symmetry D, and the magnetic barrier structure is also symmetrically arranged about the axis of symmetry D. Structurally, the magnetic poles and magnetic barrier structures are arranged in pairs, providing a uniform direct-axis permanent magnet flux to the motor. However, since the magnetic barrier structure is configured with a leading edge magnet 21 on the side where the turning edge of the D-axis is located, and a trailing edge magnet 22 on the side where the turning edge of the D-axis is located, the remanence of the leading edge magnet 21 and the trailing edge magnet 22 is different. Different grades of magnets are used for the leading and trailing poles, and the remanence B of the leading edge magnet 21 in each magnetic pole of the rotor core 2 is different. r1 Residual magnetism B along the rotor's rearward rotation of the magnet 22 r2 Small size can reduce rotor front-end magnetic circuit saturation caused by armature reaction, reduce leakage flux, and improve motor efficiency.

[0042] In this embodiment, the arrangement of permanent magnets within the magnetic barrier structure includes any one of the following: UV structure, U-shaped structure, V-shaped structure, or V-shaped structure. Since permanent magnets closer to the center of the rotor core 2 are more prone to demagnetization, the various magnetic barrier structures are arranged at intervals radially away from the center of the rotor core 2. Simultaneously, to ensure uniform magnetic flux density within the motor rotor, reduce magnetic leakage, and increase the output reluctance torque, the residual magnetism B of the leading-edge magnet 21 in each magnetic pole of the rotor core 2 is maintained. r1 Residual magnetism B along the rotor's rearward rotation of the magnet 22 r2 Smaller size improves motor efficiency.

[0043] Furthermore, the permanent magnet comprises either ferrite or neodymium iron boron (NdFeB) permanent magnets. NdFeB permanent magnets have strong demagnetization resistance, reducing the risk of motor demagnetization. Ferrite permanent magnets have a high risk of demagnetization at low temperatures, while NdFeB permanent magnets have a high risk of demagnetization at high temperatures. Since the temperature coefficients of ferrite and NdFeB permanent magnets are opposite, using permanent magnets made of ferrite or NdFeB can cope with motors under different temperature conditions, improving the motor's demagnetization resistance under different temperature operating conditions and reducing the risk of demagnetization.

[0044] Example 2:

[0045] See Figure 1-4 This invention proposes a built-in asymmetric magnetic pole rotor, comprising a rotor core 2. The rotor core 2 includes multiple magnetic barrier structures arranged circumferentially. Each magnetic barrier structure includes a leading magnet 21 on the side where the magnetic barrier structure's turning edge is located along the rotation direction of the rotor core 2, and a trailing magnet 22 on the side where the magnetic barrier structure's turning rear edge is located along the rotation direction of the rotor core 2. The coercivity of the leading magnet 21 in each magnetic barrier structure is less than the coercivity of the trailing magnet 22. The coercivity H of the turning-edge magnetic pole magnet in each magnetic pole of this invention... c1 The coercivity H of the magnetic pole magnet along the rotor direction after rotation c2 The small, balanced coercivity design ensures the demagnetization resistance of the rear steering magnet 22, providing high-speed heavy-load reliability and motor efficiency. At the same time, it reduces the coercivity of the front steering magnet 21, ensuring demagnetization resistance while reducing the cost of motor magnets.

[0046] In an optional embodiment, the coercivity of the leading magnet 21 at the leading edge of the magnetic barrier structure along the rotation direction of the rotor core 2 is H. c1 The coercivity of the trailing edge magnet 22 of the magnetic barrier structure along the rotation direction of the rotor core 2 is H. c2 , of which 0.75H c2 ≤H c1 ≤0.9H c2 .

[0047] Considering that a larger coercivity of the magnet results in a stronger resistance to demagnetization and a greater overload capacity for the motor, the coercivity of the magnet 21 at the rotor's leading edge is designed to be H. c1 The coercivity of magnet 22 along the rotor after rotation is H c2 And it satisfies 0.75H. c2 ≤H c1 ≤0.9H c2 At this time, the overall anti-demagnetization capability of the motor rotor is balanced, the field weakening speed-up capability is good, and the high-speed heavy-load efficiency is improved; if 0.75H c2 ≥H c1 The rotor's leading edge magnet 21 has weak demagnetization resistance and is easily demagnetized under high speed and heavy load; if H c1>0.9H c2 If the rotor's overall demagnetization resistance is too high, the weak magnetic current will increase when running at high speed, and the large total motor current will lead to increased copper losses and reduced motor performance.

[0048] In this embodiment, the rotor core 2 is used in a motor. The rotor core 2 also includes multiple magnetic poles arranged circumferentially. Each magnetic pole has a magnetic barrier structure composed of permanent magnets. The multiple magnetic barrier structures arranged circumferentially can improve the motor torque, and the multiple magnetic barrier structures are arranged at intervals in the radial direction away from the center of the rotor core 2. By setting multiple magnetic poles on the rotor core 2, and arranging the multiple magnetic barrier structures on the magnetic poles at intervals in the radial direction away from the center of the rotor core 2, the magnetic field stability of the rotor core 2 during rotation can be improved, torque pulsation can be reduced, the saliency ratio of the motor can be increased, and the reluctance torque of the motor can be improved. At the same time, the magnetic barrier structure is composed of permanent magnets, and the permanent magnet magnetic barrier structure provides direct-axis permanent magnet flux to the motor, increasing the torque density and permanent magnet torque of the motor.

[0049] In this embodiment, each magnetic pole is symmetrically arranged about the axis of symmetry D, and the magnetic barrier structure is also symmetrically arranged about the axis of symmetry D. Structurally, the magnetic poles and magnetic barrier structures are arranged in pairs, providing a uniform direct-axis permanent magnet flux to the motor. However, since the magnetic barrier structure is configured with a leading edge magnet 21 on the side where the turning edge of the D-axis is located, and a trailing edge magnet 22 on the side where the turning edge of the D-axis is located, permanent magnets with high coercivity have strong anti-demagnetization capabilities but are expensive. The coercivity of the leading edge magnet 21 and the trailing edge magnet 22 is different, and different grades of magnets are used for the leading and trailing poles. Furthermore, the coercivity H of the leading edge magnet 21 in each magnetic pole of the rotor core 2 is different. c1 The coercivity H of the magnet along the rotor's direction of rotation is 22. c2 Small size ensures the anti-demagnetization capability of the rear edge magnet 22, provides high-speed heavy-load reliability and motor efficiency, and reduces the cost of motor magnets.

[0050] In this embodiment, the arrangement of permanent magnets within the magnetic barrier structure includes any one of the following: UV structure, U-shaped structure, V-shaped structure, or V-shaped structure. Since permanent magnets closer to the center of the rotor core 2 are more prone to demagnetization, the various magnetic barrier structures are arranged at intervals radially away from the center of the rotor core 2. Simultaneously, to ensure uniform magnetic flux density within the motor rotor, reduce magnetic leakage, and increase the output reluctance torque, the coercivity H of the leading-edge magnet 21 in each magnetic pole of the rotor core 2 is also considered. c1 The coercivity H of the magnet along the rotor's direction of rotation is 22. c2 Smaller size reduces the coercivity of the leading edge magnet 21, ensuring anti-demagnetization capability while reducing the cost of motor magnets.

[0051] Furthermore, the permanent magnet comprises either ferrite or neodymium iron boron (NdFeB) permanent magnets. NdFeB permanent magnets have strong demagnetization resistance, reducing the risk of motor demagnetization. Ferrite permanent magnets have a high risk of demagnetization at low temperatures, while NdFeB permanent magnets have a high risk of demagnetization at high temperatures. Since the temperature coefficients of ferrite and NdFeB permanent magnets are opposite, using permanent magnets made of ferrite or NdFeB can cope with motors under different temperature conditions, improving the motor's demagnetization resistance under different temperature operating conditions and reducing the risk of demagnetization.

[0052] Example 3:

[0053] On the other hand, embodiments of the present invention also provide a built-in asymmetric magnetic pole permanent magnet motor, including a motor stator 1 wound with copper wire and a motor rotor with built-in permanent magnets. The motor rotor includes the built-in asymmetric magnetic pole rotor as described above. The motor rotor contains a plurality of magnetic barrier structures arranged circumferentially. When the motor rotor rotates, the magnetic flux density inside the motor rotor is uniform.

[0054] The motor rotor uses different grades of permanent magnets. The remanence of the magnets at the leading edge of the rotor's rotation is lower than that at the trailing edge, reducing magnetic saturation at the leading edge, minimizing external magnetic leakage, increasing output torque, and improving efficiency. Simultaneously, it enhances the coercivity of the magnets at the trailing edge, improving demagnetization resistance and reliability under high-speed, heavy-load conditions. Considering actual operating conditions, the selection of different grades of magnets at the leading and trailing edges reduces the overall cost of the permanent magnets, enhancing the motor's market competitiveness. This invention, through reasonable selection of remanence and coercivity, achieves a high-efficiency, highly demagnetized, and high-speed, heavy-load permanent magnet motor with superior performance at a lower magnet cost.

[0055] In summary, after reading this invention document, those skilled in the art can make various other corresponding modifications to the technical solutions and concepts based on this invention without creative mental effort, and all of these modifications fall within the scope of protection of this invention.

Claims

1. A built-in asymmetric magnetic pole rotor, comprising a rotor core, the rotor core including a plurality of magnetic barrier structures arranged circumferentially, characterized in that, Each of the magnetic barrier structures includes a leading magnet on the side where the magnetic barrier structure turns forward along the direction of rotation of the rotor core and a trailing magnet on the side where the magnetic barrier structure turns backward along the direction of rotation of the rotor core, wherein the remanence of the leading magnet of each of the magnetic barrier structures is less than the remanence of the trailing magnet. The remanence of the leading magnet of the magnetic barrier structure along the direction of rotor core rotation is: The remanence of the trailing edge magnet of the magnetic barrier structure along the direction of rotor core rotation is... ,in, .

2. A built-in asymmetric magnetic pole rotor, comprising a rotor core, wherein the rotor core includes a plurality of magnetic barrier structures arranged circumferentially, characterized in that, Each of the magnetic barrier structures includes a leading magnet on the side where the magnetic barrier structure turns forward along the direction of rotation of the rotor core and a trailing magnet on the side where the magnetic barrier structure turns backward along the direction of rotation of the rotor core, wherein the coercivity of the leading magnet of each magnetic barrier structure is less than the coercivity of the trailing magnet. The coercivity of the leading magnet of the magnetic barrier structure along the direction of rotor core rotation is... The coercivity of the trailing edge magnet of the magnetic barrier structure along the direction of rotor core rotation is... ,in, .

3. A built-in asymmetric magnetic pole rotor according to claim 1 or 2, characterized in that, The rotor core also includes a plurality of magnetic poles arranged circumferentially, each magnetic pole having a magnetic barrier structure composed of permanent magnets, and the plurality of magnetic barrier structures are arranged at intervals in a radial direction away from the center of the rotor core.

4. A built-in asymmetric magnetic pole rotor according to claim 3, characterized in that, Each of the magnetic poles is arranged symmetrically about the axis of symmetry D, and the magnetic barrier structure is arranged symmetrically about the axis of symmetry D.

5. A built-in asymmetric magnetic pole rotor according to claim 4, characterized in that, The magnetic barrier structure is configured with a leading edge magnet on the side where the turning edge of the D-axis is located, and a trailing edge magnet on the side where the turning edge of the D-axis is located.

6. A built-in asymmetric magnetic pole rotor according to claim 5, characterized in that, The arrangement of permanent magnets within the magnetic barrier structure includes any one of the following: UV structure, U-shaped structure, V-shaped structure, or V-type structure.

7. A built-in asymmetric magnetic pole rotor according to claim 6, characterized in that, The permanent magnet is composed of either ferrite or neodymium iron boron permanent magnet.

8. A built-in asymmetric permanent magnet motor, characterized in that, The motor includes a stator wound with copper wire and a rotor with built-in permanent magnets. The rotor includes a built-in asymmetric magnetic pole rotor as described in any one of claims 1-7. The rotor contains a plurality of magnetic barrier structures arranged circumferentially. When the rotor rotates, the magnetic flux density inside the rotor is uniform.

Images