Magnetic barrier asymmetric rotor structure of permanent magnet auxiliary synchronous reluctance motor

Abstract

The invention discloses a permanent magnet auxiliary synchronous reluctance motor magnetic barrier asymmetric rotor structure, which comprises magnetic barrier groups arranged on a rotor core along the axial direction of the rotor core, each stage of magnetic barrier group comprises three layers of radially arranged air magnetic barriers, and the air magnetic barriers are a third magnetic barrier, a second magnetic barrier and a first magnetic barrier in sequence from the center of a rotating shaft in the rotor core to a stator core; a first permanent magnet is embedded in the magnetic barrier bottom edge of the first magnetic barrier, a second permanent magnet and a sixth permanent magnet which are arranged in an axial symmetry mode are embedded in the two magnetic barrier arms of the second magnetic barrier respectively, and a third permanent magnet and a seventh permanent magnet which are arranged in an axial symmetry mode are embedded in the two magnetic barrier arms of the third magnetic barrier respectively. And a fourth permanent magnet and a fifth permanent magnet which are asymmetrically arranged are respectively embedded in the magnetic barrier bottom edges of the second magnetic barrier and the third magnetic barrier. The magnetic barrier asymmetric rotor structure has the advantages of the magnetic barrier asymmetric rotor structure, can perform offset correction on the magnetic resistance shaft, and is adaptive to optimized motors of different models.

Description

Technical Field

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

[0002] The permanent magnet assisted synchronous reluctance motor is a type of motor that combines the advantages of permanent magnets and reluctance motors. It uses permanent magnets to provide additional magnetic fields to improve the performance of reluctance motors, thereby improving overall efficiency and power density. In this type of motor, the structural design of the rotor has a great influence on the performance.

[0003] The magnetic barrier asymmetric rotor structure refers to the existence of some asymmetry in the rotor design, which makes the rotor magnetic field distribution and motor performance better optimized. The magnetic barrier asymmetric rotor structure in the permanent magnet assisted synchronous reluctance motor optimizes the magnetic field distribution and improves the motor performance through asymmetric design. It combines the advantages of permanent magnet and reluctance motors to achieve higher efficiency and power density.

[0004] Although the existing magnetic barrier asymmetric rotor structure also has the advantages of optimizing magnetic field distribution and improving motor performance, when other parts of the motor (such as stator yoke and armature winding) are optimized, its magnetic barrier asymmetric rotor structure is difficult to adjust to match them, which affects the overall magnetic field distribution and motor performance of the motor. Summary of the invention

[0005] The present invention aims at solving the problems in the prior art and proposes the following technical solutions:

[0006] A magnetic barrier asymmetric rotor structure of a permanent magnet assisted synchronous reluctance motor comprises a coaxially nested stator core and a rotor core, a stator winding is mounted on the rotor core, a magnetic barrier group is provided along the axial direction of the rotor core, and each magnetic barrier group comprises three layers of radially arranged air magnetic barriers, and the air magnetic barriers are sequentially the third magnetic barrier, the second magnetic barrier and the first magnetic barrier from the center of the rotor core rotating shaft to the stator core; the air magnetic barrier is an axial through hole with a "U"-shaped radial cross section, and the "U"-shaped axial through hole comprises a bottom edge of the magnetic barrier and two arms of the magnetic barrier;

[0007] The first magnetic barrier has a first permanent magnet embedded in its bottom edge, the second magnetic barrier has a second permanent magnet and a sixth permanent magnet embedded in its two arms in an axially symmetrical arrangement, the third magnetic barrier has a third permanent magnet and a seventh permanent magnet embedded in its two arms in an axially symmetrical arrangement, and the second and third magnetic barriers have a fourth permanent magnet and a fifth permanent magnet embedded in their bottom edges in an asymmetrical arrangement.

[0008] Preferably, the air magnetic barrier is centrally symmetrically arranged with the central rotation axis of the rotor core as the center.

[0009] Preferably, the magnetizing directions of the first permanent magnet, the fourth permanent magnet and the fifth permanent magnet are radial, and the magnetizing directions of the second permanent magnet, the third permanent magnet, the sixth permanent magnet and the seventh permanent magnet are perpendicular to the single arm direction of the magnetic barrier where they are located.

[0010] Preferably, the magnetization directions of the first permanent magnet, the fourth permanent magnet and the fifth permanent magnet in the magnetic barrier group of the same level are parallel to each other, the magnetization directions of the second permanent magnet, the third permanent magnet, the sixth permanent magnet and the seventh permanent magnet are parallel to each other, and the angle between the magnetization directions of the first permanent magnet and the second permanent magnet is an acute angle;

[0011] The magnetization directions of the first permanent magnets in the two adjacent magnetic barrier groups are opposite.

[0012] Preferably, the ends of the two arms of the air magnetic barrier open outward, and the opening angle between the two arms and the bottom edge is 135°.

[0013] Preferably, the second magnetic barrier comprises a second magnetic barrier branch a and a second magnetic barrier branch b;

[0014] The bottom edge of the magnetic barrier of the second magnetic barrier branch a is the bottom edge of branch a, the single magnetic barrier arm of the second magnetic barrier branch a is the barrier arm of branch a, the second permanent magnet is embedded in the barrier arm of branch a, and the fourth permanent magnet is embedded in the bottom edge of branch a;

[0015] The bottom edge of the magnetic barrier of the second magnetic barrier branch b is the bottom edge of branch b, and the radial cross-sectional length of the bottom edge of branch b is smaller than that of branch a. The radial cross-sectional distance between the bottom edge of branch a and the bottom edge of branch b is D1. The radial cross-sectional length ratio of the bottom edge of branch a and the bottom edge of branch b is E1. The single arm of the magnetic barrier of the second magnetic barrier branch b is the branch b barrier arm, and the sixth permanent magnet is embedded in the branch b barrier arm.

[0016] Preferably, the third magnetic barrier includes a third magnetic barrier branch f and a third magnetic barrier branch g;

[0017] The bottom edge of the magnetic barrier of the third magnetic barrier branch f is the bottom edge of branch f, the single magnetic barrier arm of the second magnetic barrier branch a is the barrier arm of branch f, and the third permanent magnet is embedded in the barrier arm of branch f;

[0018] The bottom edge of the magnetic barrier of the third magnetic barrier branch g is the bottom edge of branch g, and the radial cross-sectional length of the bottom edge of branch g is greater than that of the bottom edge of branch f, the radial cross-sectional distance between the bottom edge of branch f and the bottom edge of branch g is D2, the radial cross-sectional length ratio of the bottom edge of branch f and the bottom edge of branch g is E2, the single arm of the magnetic barrier of the third magnetic barrier branch g is the branch g barrier arm, the fifth permanent magnet is embedded in the bottom edge of branch g, and the seventh permanent magnet is embedded in the branch g barrier arm.

[0019] Preferably, the radial cross sections of the bottom edges of the branches a and g are arranged in parallel and staggered.

[0020] Preferably, when D1 and D2 are zero, that is, when E1 and E2 do not exist, the reluctance axis is the reluctance axis a; the reluctance axis of the magnetic barrier group is the reluctance axis b, and the angle between the reluctance axis a and the reluctance axis b is α.

[0021] The beneficial effects of the present invention are:

[0022] 1. In the present invention, the current angles corresponding to the maximum values ​​of the permanent magnet torque and the reluctance torque are close to the same angle by the asymmetrical arrangement of the air magnetic barrier, the reluctance axis is offset by the asymmetrical placement of the permanent magnets under the hybrid magnetic poles (i.e., the asymmetrically arranged fourth permanent magnet and fifth permanent magnet), and the reluctance axis offset effect is used to improve the efficiency and performance of the motor. The torque-current angle characteristics of the present invention achieve the maximum values ​​of the reluctance torque, the total torque and the permanent magnet torque at the same time when the current angle is 45 degrees, thereby improving the torque characteristics and thus improving the efficiency of the motor;

[0023] 2. While taking into account the advantages of the asymmetric rotor structure of the magnetic barrier, the present invention can be adjusted to adapt to different types and optimized motors by setting variables such as D1, D2, E1, E2, etc., that is, when other parts of the motor are optimized, the offset of the magnetic resistance axis can be corrected by adjusting the values ​​of D1, D2, E1, E2, etc., thereby further improving the efficiency and performance of the motor. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 What is shown is a radial cross-sectional view of the magnetic barrier asymmetric rotor structure of the permanent magnet assisted synchronous reluctance motor in the present invention;

[0025] Figure 2 The figure shows a schematic diagram of the structure of the magnetic barrier group in the magnetic barrier asymmetric rotor structure of the permanent magnet assisted synchronous reluctance motor in the present invention;

[0026] Figure 3 What is shown is a linear diagram of the load torque-current angle characteristics of the permanent magnet assisted synchronous reluctance motor with a magnetic barrier asymmetric rotor structure and a four-stage asymmetric structure in an embodiment.

[0027] 1. stator core; 2. rotor core; 3. stator winding; 40. magnetic barrier group; 41. first magnetic barrier; 42. second magnetic barrier; 421. second magnetic barrier branch a; 4211. bottom edge of branch a; 4212. barrier arm of branch a; 422. second magnetic barrier branch b; 4221. bottom edge of branch b; 4222. barrier arm of branch b; 43. third magnetic barrier; 431. third magnetic barrier branch f; 4311. bottom edge of branch f; 4312. barrier arm of branch f; 432. third magnetic barrier branch g; 4321. bottom edge of branch g; 4322. barrier arm of branch g; 51. first permanent magnet; 52. second permanent magnet; 53. third permanent magnet; 54. fourth permanent magnet; 55. fifth permanent magnet; 56. sixth permanent magnet; 57. seventh permanent magnet. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solution and advantages of the embodiments of the present invention more clear, the technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments.

[0029] Example

[0030] like Figure 1 As shown, the permanent magnet assisted synchronous reluctance motor has a magnetic barrier asymmetric rotor structure, including a coaxially nested stator core 1 and a rotor core 2, a stator winding 3 is installed on the rotor core 2, and a magnetic barrier group 40 is opened along the axial direction of the rotor core 2, and each magnetic barrier group 40 includes three layers of radially arranged air magnetic barriers, and the air magnetic barriers are the third magnetic barrier 43, the second magnetic barrier 42 and the first magnetic barrier 41 from the center of the rotating shaft of the rotor core 2 to the stator core 1 in sequence; the air magnetic barrier is an axial through hole with a "U"-shaped radial cross section, and the "U"-shaped axial through hole includes a bottom edge of the magnetic barrier and two arms of the magnetic barrier;

[0031] The first permanent magnet 51 is embedded in the bottom edge of the first magnetic barrier 41, the second permanent magnet 52 and the sixth permanent magnet 56 are respectively embedded in the two arms of the second magnetic barrier 42, the third permanent magnet 53 and the seventh permanent magnet 57 are respectively embedded in the two arms of the third magnetic barrier 43, and the fourth permanent magnet 54 and the fifth permanent magnet 55 are respectively embedded in the bottom edges of the second magnetic barrier 42 and the third magnetic barrier 43.

[0032] like Figure 3As shown, in the present invention, the current angles corresponding to the maximum values ​​of the permanent magnet torque and the reluctance torque are close to the same angle by asymmetrically placing the permanent magnets under the hybrid poles (i.e., the asymmetrically arranged fourth permanent magnet 54 and the fifth permanent magnet 55), so that the reluctance axis is offset, and the reluctance axis offset effect is used to improve the efficiency and performance of the motor. The torque-current angle characteristics of the present invention achieve the maximum values ​​of the reluctance torque, total torque and permanent magnet torque at the same time when the current angle is 45 degrees, thereby improving the torque characteristics and thus improving the efficiency of the motor.

[0033] Furthermore, the air magnetic barriers are centrally symmetrically arranged with the central rotation axis of the rotor core 2 as the center.

[0034] Furthermore, the magnetization directions of the first permanent magnet 51, the fourth permanent magnet 54, and the fifth permanent magnet 55 are radial, and the magnetization directions of the second permanent magnet 52, the third permanent magnet 53, the sixth permanent magnet 56, and the seventh permanent magnet 57 are perpendicular to the single arm direction of the magnetic barrier where they are located. The magnetization directions of the first permanent magnet 51, the fourth permanent magnet 54, and the fifth permanent magnet 55 in the same level magnetic barrier group 40 are parallel to each other in the same direction, and the magnetization directions of the second permanent magnet 52, the third permanent magnet 53, the sixth permanent magnet 56, and the seventh permanent magnet 57 are parallel to each other in the same direction, and the angle between the magnetization directions of the first permanent magnet 51 and the second permanent magnet 52 is an acute angle; the magnetization directions of the first permanent magnet 51 in two adjacent levels of magnetic barrier groups 40 are opposite.

[0035] like Figure 2 As shown, the ends of the two arms of the air magnetic barrier are open outward, and the opening angle between the two arms and the bottom edge is 135°. The second magnetic barrier 42 includes a second magnetic barrier branch a421 and a second magnetic barrier branch b422;

[0036] The bottom edge of the magnetic barrier of the second magnetic barrier branch a421 is the bottom edge 4211 of branch a, the single magnetic barrier arm of the second magnetic barrier branch a421 is the barrier arm 4212 of branch a, the second permanent magnet 52 is embedded in the barrier arm 4212 of branch a, and the fourth permanent magnet 54 is embedded in the bottom edge 4211 of branch a;

[0037] The bottom edge of the magnetic barrier of the second magnetic barrier branch b422 is the bottom edge 4221 of branch b, and the radial cross-sectional length of the bottom edge 4221 of branch b is smaller than the bottom edge 4211 of branch a, the radial cross-sectional distance between the bottom edge 4211 of branch a and the bottom edge 4221 of branch b is D1, the radial cross-sectional length ratio between the bottom edge 4211 of branch a and the bottom edge 4221 of branch b is E1, the single arm of the magnetic barrier of the second magnetic barrier branch b422 is the branch b barrier arm 4222, and the sixth permanent magnet 56 is embedded in the branch b barrier arm 4222.

[0038] The third magnetic barrier 43 includes a third magnetic barrier branch f431 and a third magnetic barrier branch g432;

[0039] The bottom edge of the magnetic barrier of the third magnetic barrier branch f431 is the bottom edge 4311 of the branch f, the single arm of the magnetic barrier of the second magnetic barrier branch a421 is the branch f barrier arm 4312, and the third permanent magnet 53 is embedded in the branch f barrier arm 4312;

[0040] The bottom edge of the magnetic barrier of the third magnetic barrier branch g432 is the bottom edge 4321 of branch g, and the radial cross-sectional length of the bottom edge 4321 of branch g is greater than that of the bottom edge 4311 of branch f, the radial cross-sectional distance between the bottom edge 4311 of branch f and the bottom edge 4321 of branch g is D2, the radial cross-sectional length ratio of the bottom edge 4311 of branch f and the bottom edge 4321 of branch g is E2, the single arm of the magnetic barrier of the third magnetic barrier branch g432 is the branch g barrier arm 4322, the fifth permanent magnet 55 is embedded in the bottom edge 4321 of branch g, and the seventh permanent magnet 57 is embedded in the branch g barrier arm 4322.

[0041] The radial cross sections of the bottom edge 4211 of branch a and the bottom edge 4321 of branch g are arranged in parallel and staggered.

[0042] While taking into account the advantages of the asymmetric rotor structure of the magnetic barrier, the present invention can be adjusted to adapt to different types and optimized motors by setting variables such as D1, D2, E1, E2, etc., that is, when other parts of the motor are optimized, the offset of the magnetic resistance axis can be corrected by adjusting the values ​​of D1, D2, E1, E2, etc., thereby further improving the efficiency and performance of the motor.

[0043] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them.

Claims

1. A permanent magnet assisted synchronous reluctance motor with a magnetic barrier asymmetric rotor structure, comprising a coaxially nested stator core (1) and a rotor core (2), wherein a stator winding (3) is mounted on the rotor core (2), characterized in that: The rotor core (2) is provided with a magnetic barrier group (40) along its axial direction, and each level of the magnetic barrier group (40) includes three layers of radially arranged air magnetic barriers, and the air magnetic barriers are sequentially a third magnetic barrier (43), a second magnetic barrier (42), and a first magnetic barrier (41) from the center of the rotor core (2) central axis to the stator core (1); the air magnetic barrier is an axial through hole with a "U"-shaped radial cross section, and the "U"-shaped axial through hole includes a magnetic barrier bottom edge and two magnetic barrier arms; The first magnetic barrier (41) has a first permanent magnet (51) embedded in the bottom edge of the magnetic barrier, the second magnetic barrier (42) has a second permanent magnet (52) and a sixth permanent magnet (56) embedded in the two arms of the magnetic barrier respectively, the third magnetic barrier (43) has a third permanent magnet (53) and a seventh permanent magnet (57) embedded in the two arms of the magnetic barrier respectively, and the second magnetic barrier (42) and the third magnetic barrier (43) have a fourth permanent magnet (54) and a fifth permanent magnet (55) embedded in the bottom edges of the magnetic barriers respectively.

2. The permanent magnet assisted synchronous reluctance motor magnetic barrier asymmetric rotor structure according to claim 1, characterized in that: The air magnetic barrier is centrally symmetrically arranged with the central rotation axis of the rotor core (2) as the center.

3. The permanent magnet assisted synchronous reluctance motor magnetic barrier asymmetric rotor structure according to claim 1, characterized in that: The magnetization directions of the first permanent magnet (51), the fourth permanent magnet (54) and the fifth permanent magnet (55) are radial, and the magnetization directions of the second permanent magnet (52), the third permanent magnet (53), the sixth permanent magnet (56) and the seventh permanent magnet (57) are perpendicular to the single arm direction of the magnetic barrier where they are located.

4. The permanent magnet assisted synchronous reluctance motor magnetic barrier asymmetric rotor structure according to claim 3, characterized in that: The magnetization directions of the first permanent magnet (51), the fourth permanent magnet (54) and the fifth permanent magnet (55) in the magnetic barrier group (40) of the same level are parallel to each other, the magnetization directions of the second permanent magnet (52), the third permanent magnet (53), the sixth permanent magnet (56) and the seventh permanent magnet (57) are parallel to each other, and the angle between the magnetization directions of the first permanent magnet (51) and the second permanent magnet (52) is an acute angle; The magnetization directions of the first permanent magnets (51) in the two adjacent magnetic barrier groups (40) are opposite.

5. The permanent magnet assisted synchronous reluctance motor magnetic barrier asymmetric rotor structure according to claim 1, characterized in that: The ends of the two arms of the air magnetic barrier are opened outwards, and the opening angle between the two arms and the bottom edge is 135°.

6. The permanent magnet assisted synchronous reluctance motor magnetic barrier asymmetric rotor structure according to claim 1, characterized in that: The second magnetic barrier (42) comprises a second magnetic barrier branch a (421) and a second magnetic barrier branch b (422); The bottom edge of the magnetic barrier of the second magnetic barrier branch a (421) is the bottom edge of branch a (4211), the single magnetic barrier arm of the second magnetic barrier branch a (421) is the barrier arm of branch a (4212), the second permanent magnet (52) is embedded in the barrier arm of branch a (4212), and the fourth permanent magnet (54) is embedded in the bottom edge of branch a (4211); The bottom edge of the magnetic barrier of the second magnetic barrier branch b (422) is the bottom edge of branch b (4221), and the radial cross-sectional length of the bottom edge of branch b (4221) is smaller than that of the bottom edge of branch a (4211), the radial cross-sectional distance between the bottom edge of branch a (4211) and the bottom edge of branch b (4221) is D1, the radial cross-sectional length ratio between the bottom edge of branch a (4211) and the bottom edge of branch b (4221) is E1, the single arm of the magnetic barrier of the second magnetic barrier branch b (422) is the branch b barrier arm (4222), and the sixth permanent magnet (56) is embedded in the branch b barrier arm (4222).

7. The permanent magnet assisted synchronous reluctance motor magnetic barrier asymmetric rotor structure according to claim 6, characterized in that: The third magnetic barrier (43) comprises a third magnetic barrier branch f (431) and a third magnetic barrier branch g (432); The bottom edge of the magnetic barrier of the third magnetic barrier branch f (431) is the bottom edge of branch f (4311), the single arm of the magnetic barrier of the second magnetic barrier branch a (421) is the branch f barrier arm (4312), and the third permanent magnet (53) is embedded in the branch f barrier arm (4312); The bottom edge of the magnetic barrier of the third magnetic barrier branch g (432) is the bottom edge of branch g (4321), and the radial cross-sectional length of the bottom edge of branch g (4321) is greater than that of the bottom edge of branch f (4311), the radial cross-sectional distance between the bottom edge of branch f (4311) and the bottom edge of branch g (4321) is D2, the radial cross-sectional length ratio between the bottom edge of branch f (4311) and the bottom edge of branch g (4321) is E2, the magnetic barrier single arm of the third magnetic barrier branch g (432) is the branch g barrier arm (4322), the fifth permanent magnet (55) is embedded in the bottom edge of branch g (4321), and the seventh permanent magnet (57) is embedded in the branch g barrier arm (4322).

8. The permanent magnet assisted synchronous reluctance motor magnetic barrier asymmetric rotor structure according to claim 7, characterized in that: The radial cross sections of the bottom edge (4211) of branch a and the bottom edge (4321) of branch g are arranged in parallel and staggered.

9. The permanent magnet assisted synchronous reluctance motor magnetic barrier asymmetric rotor structure according to claim 8, characterized in that: When D1 and D2 are zero, that is, when E1 and E2 do not exist, the reluctance axis is the reluctance axis a; the reluctance axis of the magnetic barrier group (40) is the reluctance axis b, and the angle between the reluctance axis a and the reluctance axis b is α.

Images