Multilayer combined magnetic pole type permanent magnet motor

Abstract

The invention provides a multilayer combined magnetic pole type permanent magnet motor, and belongs to the technical field of automobile motor electric appliances. The first-class U-shaped grooves, the second-class U-shaped grooves and the third-class U-shaped grooves are sequentially arranged at intervals outwards in the radial direction of the rotor iron core, the second-class U-shaped grooves are located in openings of the first-class U-shaped grooves, the third-class U-shaped grooves are located in openings of the second-class U-shaped grooves, a fourth-class U-shaped groove and a fifth-class U-shaped groove are formed between every two adjacent first-class U-shaped grooves, and the fourth-class U-shaped groove and the fifth-class U-shaped groove are located in openings of the second-class U-shaped grooves. The fifth type U-shaped groove is located in an opening of the fourth type U-shaped groove, the second type U-shaped groove and the fourth type U-shaped groove are symmetrical about the left side wing or the right side wing of the first type U-shaped groove, and the fifth type U-shaped groove and the third type U-shaped groove are symmetrical about the left side wing or the right side wing of the first type U-shaped groove. By adopting a mode that each layer of permanent magnet poles are combined with permanent magnets with different lengths through magnetic barriers, the direction of a rotor magnetic field is adjusted, magnetic saturation is avoided, the output capacity is improved, wide magnetic conduction paths are provided between adjacent layers, and the utilization rate of the permanent magnets is improved.

Description

Technical Field

[0001] The invention provides a multi-layer combined magnetic pole type permanent magnet motor, belonging to the technical field of automobile motors and electrical appliances. Background Art

[0002] At present, methods for reducing the magnetic flux distortion rate of motors have been proposed, such as the prior art, the published Chinese patent, combined magnetic pole neodymium iron boron permanent magnet drive motor, application number: 202020718132.9, discloses a motor in which the magnetic field in the air gap is provided by a tangential permanent magnetic field and a double radial permanent magnetic field. The air gap magnetic flux is sinusoidally distributed and has a small distortion rate, which improves the utilization rate of permanent magnets and output efficiency. The published Chinese patent, a high-torque permanent magnet motor, application number: 201710217793.6, discloses a rotor structure with N double-layer magnetic steel slots distributed along the circumference of the rotor, and gaps are provided between adjacent magnetic steels. More magnetic steels increase the magnetic flux and power density per pole of the rotor. The magnetic poles are symmetrical about the magnetic pole center, and the magnetic flux waveform distortion rate and cogging torque are increased. The total weight of the rotor is heavy, and the motor power is reduced. Summary of the invention

[0003] The technical problem to be solved by the present invention is: under the premise of ensuring that the processing procedures are not increased, the process difficulty and the motor cost are not greatly changed, the shortcomings of the prior art are overcome and a multi-layer combined magnetic pole type permanent magnet motor is provided. The internal structure of the motor magnetic pole is asymmetric about the magnetic pole center, and the left and right pole arc lengths between adjacent permanent magnet layers are not equal, which can reduce the magnetic flux density distortion rate. At the same time, each layer of permanent magnet poles is composed of a magnetic barrier combined with permanent magnets of different lengths to adjust the direction of the rotor magnetic field, avoid magnetic saturation, and improve output capacity. At the same time, a wide magnetic conduction path is provided between adjacent layers to improve the utilization rate of the permanent magnet.

[0004] The technical solution adopted by the present invention to solve the technical problem is: a multi-layer combined magnetic pole type permanent magnet motor, including a rotating shaft, a front cover, a housing, a stator, a rear cover, a rotor core, a first type U-shaped groove, a second type U-shaped groove, a third type U-shaped groove, a fourth type U-shaped groove, a fifth type U-shaped groove, and permanent magnet steel, characterized in that: The first type U-shaped groove, the second type U-shaped groove, and the third type U-shaped groove are sequentially spaced outwardly along the radial direction of the rotor core, the second type U-shaped groove is located in the opening of the first type U-shaped groove, and the third type U-shaped groove is located in the opening of the second type U-shaped groove; A fourth type of U-shaped groove and a fifth type of U-shaped groove are provided between two adjacent first type of U-shaped grooves, and the fifth type of U-shaped groove is located in the opening of the fourth type of U-shaped groove; The second type of U-shaped groove and the fourth type of U-shaped groove are symmetrical about the left wing or the right wing of the first type of U-shaped groove; The fifth type of U-shaped groove and the third type of U-shaped groove are symmetrical about the left wing or the right wing of the first type of U-shaped groove; The left wing of the first type of U-shaped groove is the first magnetic isolation groove, the right wing of the first type of U-shaped groove is the first magnetic steel groove, the lower wing of the first type of U-shaped groove is the second magnetic steel groove and the second magnetic isolation groove, the left wing of the second type of U-shaped groove is the third magnetic steel groove, the right wing of the second type of U-shaped groove is the third magnetic isolation groove, the lower wing of the second type of U-shaped groove is the fourth magnetic steel groove and the fifth magnetic steel groove, the left wing of the third type of U-shaped groove is the fourth magnetic isolation groove, the right wing of the third type of U-shaped groove is the sixth magnetic steel groove, the lower wing of the third type of U-shaped groove is the seventh magnetic steel groove, the left wing of the fourth type of U-shaped groove is the fifth magnetic isolation groove, the right wing of the fourth type of U-shaped groove is the eighth magnetic steel groove, the lower wing of the fourth type of U-shaped groove is the ninth magnetic steel groove and the tenth magnetic steel groove, the left wing of the fifth type of U-shaped groove is the eleventh magnetic steel groove, the right wing of the fifth type of U-shaped groove is the sixth magnetic isolation groove, and the lower wing of the fifth type of U-shaped groove is the twelfth magnetic steel groove; Permanent magnets are placed in the first magnetic steel slot, the second magnetic steel slot, the third magnetic steel slot, the fourth magnetic steel slot, the fifth magnetic steel slot, the sixth magnetic steel slot, the seventh magnetic steel slot, the eighth magnetic steel slot, the ninth magnetic steel slot, the tenth magnetic steel slot, the eleventh magnetic steel slot, and the twelfth magnetic steel slot, respectively.

[0005] The second magnetic steel slot is close to one end of the first magnetic isolation slot, the second magnetic isolation slot is close to one end of the first magnetic steel slot, the fourth magnetic steel slot is close to one end of the third magnetic steel slot, and the fifth magnetic steel slot is close to one end of the third magnetic isolation slot; The minimum distance between the second magnetic steel slot, the fourth magnetic steel slot, the fifth magnetic steel slot, the sixth magnetic steel slot, the seventh magnetic steel slot, the ninth magnetic steel slot, the tenth magnetic steel slot, the eleventh magnetic steel slot, the twelfth magnetic steel slot, the second magnetic isolation slot and the proximal end of the center line of the magnetic pole is 0.75mm.

[0006] The center line of the second magnetic steel slot parallel to the long side of the second magnetic steel slot and the center line of the second magnetic isolation slot parallel to the long side of the second magnetic isolation slot are on the same straight line. The center line of the fourth magnetic steel slot parallel to the long side of the fourth magnetic steel slot and the center line of the fifth magnetic steel slot parallel to the long side of the fifth magnetic steel slot are on the same straight line.

[0007] The pole arc length between the left end of the first type U-shaped slot and the left end of the second type U-shaped slot is a, the pole arc length between the right end of the first type U-shaped slot and the right end of the second type U-shaped slot is b, the ratio of a to b is equal to the ratio of the length of the second magnetic steel slot to the length of the first magnetic steel slot, the pole arc length between the left end of the second type U-shaped slot and the left end of the third type U-shaped slot is c, the pole arc length between the right end of the second type U-shaped slot and the right end of the third type U-shaped slot is d, the ratio of c to d is equal to the ratio of the sum of the lengths of the third magnetic steel slot and the fourth magnetic steel slot to the length of the fifth magnetic steel slot.

[0008] Compared with the prior art, the present invention has the following technical effects: (1) The lengths of the left and right pole arcs between adjacent permanent magnet layers are not equal, which reduces the magnetic flux density waveform distortion rate and improves efficiency; (2) Each layer of permanent magnet poles is composed of magnetic barriers and permanent magnets of different lengths to adjust the direction of the rotor magnetic field, avoid magnetic saturation, and improve output capacity. At the same time, a wide magnetic conduction path is provided between adjacent layers to improve the utilization rate of permanent magnets. (3) The asymmetric structure of the magnetic pole inside the magnetic pole about the magnetic pole center can weaken the cogging torque; (4) The setting of magnetic barriers can reduce the weight of the rotor and improve the power density of the whole machine; (5) Some permanent magnet steel is processed in sections to reduce eddy current losses and improve motor reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 It is a schematic diagram of the motor structure of the present invention.

[0010] Figure 2 It is a schematic diagram of the rotor structure of the present invention.

[0011] In the figure: 1. rotating shaft; 2. front end cover; 3. casing; 4. stator; 5. rear end cover; 6. rotor core; 7. first type U-shaped groove; 8. second type U-shaped groove; 9. third type U-shaped groove; 10. fourth type U-shaped groove; 11. fifth type U-shaped groove. DETAILED DESCRIPTION

[0012] The present invention will be further described below in conjunction with the accompanying drawings.

[0013] A multi-layer combined magnetic pole type permanent magnet motor, comprising a rotating shaft 1, a front end cover 2, a housing 3, a stator 4, a rear end cover 5, a rotor core 6, a first type U-shaped groove 7, a second type U-shaped groove 8, a third type U-shaped groove 9, a fourth type U-shaped groove 10, a fifth type U-shaped groove 11, and permanent magnet steel, characterized in that: The first type U-shaped groove 7, the second type U-shaped groove 8, and the third type U-shaped groove 9 are sequentially spaced outwardly along the radial direction of the rotor core 6, the second type U-shaped groove 8 is located in the opening of the first type U-shaped groove 7, and the third type U-shaped groove 9 is located in the opening of the second type U-shaped groove 8; A fourth type U-shaped groove 10 and a fifth type U-shaped groove 11 are provided between two adjacent first type U-shaped grooves 7 and are located in the opening of the fourth type U-shaped groove 10; The left side wing of the first type of U-shaped groove 7 is the first magnetic steel groove, the right side wing of the first type of U-shaped groove 7 is the first magnetic steel groove, the lower side wing of the first type of U-shaped groove 7 is the second magnetic steel groove and the second magnetic steel groove, the left side wing of the second type of U-shaped groove 8 is the third magnetic steel groove, the right side wing of the second type of U-shaped groove 8 is the third magnetic steel groove, the lower side wing of the second type of U-shaped groove 8 is the fourth magnetic steel groove and the fifth magnetic steel groove, the left side wing of the third type of U-shaped groove 9 is the fourth magnetic steel groove, and the right side of the third type of U-shaped groove 9 is the The wing is the sixth magnetic steel groove, the lower wing of the third type U-shaped groove 9 is the seventh magnetic steel groove, the left wing of the fourth type U-shaped groove 10 is the fifth magnetic isolation groove, the right wing of the fourth type U-shaped groove 10 is the eighth magnetic steel groove, the lower wing of the fourth type U-shaped groove 10 is the ninth magnetic steel groove and the tenth magnetic steel groove, the left wing of the fifth type U-shaped groove 11 is the eleventh magnetic steel groove, the right wing of the fifth type U-shaped groove 11 is the sixth magnetic isolation groove, and the lower wing of the fifth type U-shaped groove 11 is the twelfth magnetic steel groove; The symmetry axes of the first magnetic steel groove, the second type U-shaped groove 8 on the left side of the first magnetic steel groove, and the fourth type U-shaped groove 10 on the right side of the first magnetic steel groove coincide with each other; The symmetry axes of the first magnetic steel slot, the third type U-shaped slot 9 on the left side of the first magnetic steel slot, and the fifth type U-shaped slot 11 on the right side of the first magnetic steel slot coincide with each other; The symmetry axes of the first magnetic isolation groove, the fourth type of U-shaped groove 10 on the left side of the first magnetic isolation groove, and the second type of U-shaped groove 8 on the right side of the first magnetic isolation groove coincide with each other; The symmetry axes of the first magnetic isolation groove, the fifth type of U-shaped groove 11 on the left side of the first magnetic isolation groove, and the third type of U-shaped groove 9 on the right side of the first magnetic isolation groove coincide with each other; Permanent magnets are placed in the first magnetic steel slot, the second magnetic steel slot, the third magnetic steel slot, the fourth magnetic steel slot, the fifth magnetic steel slot, the sixth magnetic steel slot, the seventh magnetic steel slot, the eighth magnetic steel slot, the ninth magnetic steel slot, the tenth magnetic steel slot, the eleventh magnetic steel slot, and the twelfth magnetic steel slot, respectively.

[0014] The second magnetic steel slot is close to one end of the first magnetic isolation slot, the second magnetic isolation slot is close to one end of the first magnetic steel slot, the fourth magnetic steel slot is close to one end of the third magnetic steel slot, and the fifth magnetic steel slot is close to one end of the third magnetic isolation slot; The minimum distance between the second magnetic steel slot, the fourth magnetic steel slot, the fifth magnetic steel slot, the sixth magnetic steel slot, the seventh magnetic steel slot, the ninth magnetic steel slot, the tenth magnetic steel slot, the eleventh magnetic steel slot, the twelfth magnetic steel slot, the second magnetic isolation slot and the proximal end of the center line of the magnetic pole is 0.75mm.

[0015] The center line of the second magnetic steel slot parallel to the long side and the center line of the second magnetic isolation slot parallel to the long side are on the same straight line, and the center line of the fourth magnetic steel slot parallel to the long side and the center line of the fifth magnetic steel slot parallel to the long side are on the same straight line.

[0016] The pole arc length between the left end of the first type U-shaped slot 7 and the left end of the second type U-shaped slot 8 is a, and the pole arc length between the right end of the first type U-shaped slot 7 and the right end of the second type U-shaped slot 8 is b. The ratio of a to b is equal to the ratio of the length of the second magnetic steel slot to the length of the first magnetic steel slot; the pole arc length between the left end of the second type U-shaped slot 8 and the left end of the third type U-shaped slot 9 is c, and the pole arc length between the right end of the second type U-shaped slot 8 and the right end of the third type U-shaped slot 9 is d. The ratio of c to d is equal to the ratio of the sum of the lengths of the third magnetic steel slot and the fourth magnetic steel slot to the length of the fifth magnetic steel slot.

Claims

1. A multi-layer combined magnetic pole type permanent magnet motor, comprising a rotating shaft (1), a front end cover (2), a housing (3), a stator (4), a rear end cover (5), a rotor core (6), a first type U-shaped groove (7), a second type U-shaped groove (8), a third type U-shaped groove (9), a fourth type U-shaped groove (10), a fifth type U-shaped groove (11), and permanent magnet steel, characterized in that: The first type U-shaped groove (7), the second type U-shaped groove (8), and the third type U-shaped groove (9) are arranged in sequence and spaced apart from each other in a radial direction outwardly of the rotor core (6); the second type U-shaped groove (8) is located in an opening of the first type U-shaped groove (7), and the third type U-shaped groove (9) is located in an opening of the second type U-shaped groove (8); A fourth type of U-shaped groove (10) and a fifth type of U-shaped groove (11) are provided between two adjacent first type of U-shaped grooves (7), and the fifth type of U-shaped groove (11) is located in the opening of the fourth type of U-shaped groove (10); The second type of U-shaped groove (8) and the fourth type of U-shaped groove (10) are symmetrical about the left wing or the right wing of the first type of U-shaped groove (7); The fifth type of U-shaped groove (11) and the third type of U-shaped groove (9) are symmetrical about the left wing or the right wing of the first type of U-shaped groove (7); The left wing of the first type of U-shaped groove (7) is the first magnetic isolation groove, the right wing of the first type of U-shaped groove (7) is the first magnetic steel groove, the lower wing of the first type of U-shaped groove (7) is the second magnetic steel groove and the second magnetic isolation groove, the left wing of the second type of U-shaped groove (8) is the third magnetic steel groove, the right wing of the second type of U-shaped groove (8) is the third magnetic isolation groove, the lower wing of the second type of U-shaped groove (8) is the fourth magnetic steel groove and the fifth magnetic steel groove, the left wing of the third type of U-shaped groove (9) is the fourth magnetic isolation groove, and the right wing of the third type of U-shaped groove (9) is the third magnetic isolation groove. The side wing is the sixth magnetic steel groove, the lower side wing of the third type U-shaped groove (9) is the seventh magnetic steel groove, the left side wing of the fourth type U-shaped groove (10) is the fifth magnetic isolation groove, the right side wing of the fourth type U-shaped groove (10) is the eighth magnetic steel groove, the lower side wing of the fourth type U-shaped groove (10) is the ninth magnetic steel groove and the tenth magnetic steel groove, the left side wing of the fifth type U-shaped groove (11) is the eleventh magnetic steel groove, the right side wing of the fifth type U-shaped groove (11) is the sixth magnetic isolation groove, and the lower side wing of the fifth type U-shaped groove (11) is the twelfth magnetic steel groove; Permanent magnets are placed in the first magnetic steel slot, the second magnetic steel slot, the third magnetic steel slot, the fourth magnetic steel slot, the fifth magnetic steel slot, the sixth magnetic steel slot, the seventh magnetic steel slot, the eighth magnetic steel slot, the ninth magnetic steel slot, the tenth magnetic steel slot, the eleventh magnetic steel slot, and the twelfth magnetic steel slot, respectively.

2. The multi-layer combined magnetic pole type permanent magnet motor according to claim 1, characterized in that: The second magnetic steel slot is close to one end of the first magnetic isolation slot, the second magnetic isolation slot is close to one end of the first magnetic steel slot, the fourth magnetic steel slot is close to one end of the third magnetic steel slot, and the fifth magnetic steel slot is close to one end of the third magnetic isolation slot; The minimum distance between the second magnetic steel slot, the fourth magnetic steel slot, the fifth magnetic steel slot, the sixth magnetic steel slot, the seventh magnetic steel slot, the ninth magnetic steel slot, the tenth magnetic steel slot, the eleventh magnetic steel slot, the twelfth magnetic steel slot, the second magnetic isolation slot and the proximal end of the center line of the magnetic pole is 0.75mm.

3. The multi-layer combined magnetic pole type permanent magnet motor according to claim 1, characterized in that: The center line of the second magnetic steel slot parallel to the long side of the second magnetic steel slot and the center line of the second magnetic isolation slot parallel to the long side of the second magnetic isolation slot are on the same straight line. The center line of the fourth magnetic steel slot parallel to the long side of the fourth magnetic steel slot and the center line of the fifth magnetic steel slot parallel to the long side of the fifth magnetic steel slot are on the same straight line.

4. The multi-layer combined magnetic pole type permanent magnet motor according to claim 1, characterized in that: The pole arc length between the left end of the first type U-shaped groove (7) and the left end of the second type U-shaped groove (8) is a, the pole arc length between the right end of the first type U-shaped groove (7) and the right end of the second type U-shaped groove (8) is b, the ratio of a to b is equal to the ratio of the length of the second magnetic steel groove to the length of the first magnetic steel groove, the pole arc length between the left end of the second type U-shaped groove (8) and the left end of the third type U-shaped groove (9) is c, the pole arc length between the right end of the second type U-shaped groove (8) and the right end of the third type U-shaped groove (9) is d, the ratio of c to d is equal to the ratio of the sum of the lengths of the third magnetic steel groove and the fourth magnetic steel groove to the length of the fifth magnetic steel groove.

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