CN112421827A

CN112421827A - Rotor and motor

Info

Publication number: CN112421827A
Application number: CN202011402867.1A
Authority: CN
Inventors: 韩永杰; 刘钧; 杨深; 蒋奎; 纪科星
Original assignee: Shanghai Weimeisi New Energy Co ltd
Current assignee: Shanghai Weimeisi New Energy Co ltd
Priority date: 2020-12-04
Filing date: 2020-12-04
Publication date: 2021-02-26
Also published as: WO2022116533A1

Abstract

The invention discloses a rotor and a motor, wherein the rotor comprises an iron core and a magnetic steel groove group, the magnetic steel groove group comprises two first magnetic steel grooves distributed in a V shape, magnetic steel is arranged in the first magnetic steel grooves, a magnetic bridge is arranged between the two first magnetic steel grooves, and the first magnetic steel grooves comprise: the first convex part and the second convex part are arranged close to the magnetic bridge and face the inner part of the first magnetic steel groove, and the concave part is arranged on the groove wall; the first magnetic steel groove also comprises an extension groove which is arranged on one side of the magnetic bridge and extends towards the radial direction of the iron core; the magnetic steel slot group also comprises two second magnetic steel slots distributed in a V shape. Compared with the prior art, the invention can relieve the demagnetization effect of the demagnetization magnetic field on the corners of the magnetic steel, and meanwhile, the invention can not influence the output torque of the motor.

Description

Rotor and motor

Technical Field

The invention relates to the field of motors, in particular to a rotor and a motor.

Background

Environmental pollution and energy crisis promote the rapid development of the new energy automobile industry, especially the electric automobile industry, and the vehicle driving motor is one of the key execution parts of the electric automobile, and the performance of the vehicle driving motor is very important for the performance of the whole automobile. Because of the advantages of high power density, high efficiency and the like, the permanent magnet motor is widely applied to the field of vehicle driving motors, and has the advantages of simple structure, small volume, low loss, high efficiency, easiness in control and the like. In order to increase the power density of the driving system, a permanent magnet motor and a speed reducer are usually used to provide driving force for the electric vehicle, or a three-in-one assembly with high integration of the motor, the speed reducer and a motor controller is adopted.

However, due to the special operation condition of the electric vehicle, the motor is required to have higher torque density, that is, the motor is required to have smaller volume while needing large torque; in the prior art, some motors are overlapped to increase the output torque of the motors, but the volume of the motors is also increased; the output torque of motor can be improved to the magnet steel that can use high-performance magnetism in addition, but the cost that high-performance magnet steel also can make the motor improves to high-performance magnet steel also can lead to the saturation of magnetic circuit, and then makes the iron loss increase, improves magnet steel remanence simultaneously and is limited to the promotion of torque performance, and when reaching certain degree, the torque performance of motor just can't further promote.

Meanwhile, in the prior art, when the usage amount of the magnetic steel is the same, the thickness of the rotor magnetic bridge affects the magnetic flux leakage of the magnetic steel, the larger thickness of the magnetic bridge increases the magnetic flux leakage, and further reduces the output torque of the motor, so that in order to obtain the larger output torque, the thickness of the magnetic bridge needs to be reduced as much as possible, but the demagnetization state of the magnetic steel of the motor is aggravated if the thickness of the magnetic bridge is too small, mainly because the smaller thickness of the magnetic bridge inhibits the trend of the demagnetization magnetic field, so that the demagnetization magnetic field is biased to pass through the magnetic steel of the motor in a concentrated manner, and the demagnetization state of the magnetic field is aggravated; the demagnetization rate of magnet steel is reduced to the quantity that also can increase magnet steel, guarantees the stability of motor, but the increase of magnet steel quantity also can increase the cost of motor to the increase of magnet steel quantity also can make the rotor at the mechanical strength variation of centrifugal force effect.

Therefore, it is necessary to design a rotor having excellent demagnetization resistance to ensure the output torque of the motor without increasing the volume and cost.

Disclosure of Invention

The invention provides a rotor and a motor, which can be designed to have excellent demagnetization resistance on the premise of not increasing the size and the cost and ensuring the output torque of the motor.

The technical scheme adopted by the invention is as follows: the utility model provides a rotor, includes iron core and magnet steel slot group, magnet steel slot group includes that two are the V-arrangement and distribute and the most advanced direction of V-arrangement is towards the first magnet steel slot at iron core center, be equipped with the magnet steel in the first magnet steel slot, and two it is the magnetic bridge to lie in V-arrangement point department between the first magnet steel slot, first magnet steel slot includes: and the first convex part is close to the magnetic bridge and protrudes towards the inside of the first magnetic steel groove.

Furthermore, the first magnetic steel groove comprises a first groove wall and a second groove wall which extend from the V-shaped tip to the opening direction, the magnetic steel is embedded between the first groove wall and the second groove wall, the first groove wall is arranged on the inner side of the V-shaped groove, the magnetic steel comprises a first end part and a second end part which are arranged at an included angle with the first groove wall, the first end part is arranged towards the V-shaped opening direction, and the second end part is arranged towards the V-shaped tip direction; the first magnetic steel groove further comprises a second convex part which is arranged on the first groove wall and is close to the first end part.

Further, the first magnetic steel groove further comprises a concave part which is arranged on the first groove wall and is close to the second end part.

Preferably, the first protrusion is an arc protrusion, the first protrusion is disposed on the first slot wall and at an included angle with the magnetic bridge, a distance H1 from a protruding end of the first protrusion to the first slot wall is 0.6mm to 0.8mm, and a maximum distance L1 from the first protrusion to the magnetic bridge is 0.6mm to 0.8 mm.

Preferably, the second convex part is an arc-shaped convex part, and the protruding height H2 of the second convex part relative to the first groove wall is 0.15mm to 0.3 mm; the radius of the second convex part is R, and the distance between the circle center of the second convex part and the first end part is 0.9R to 1.1R.

Preferably, the recess is an arc-shaped notch, the maximum recess depth H3 of the recess is 0.3mm to 0.5mm, and the distance from the center of the recess to the second end is 0.1mm to 0.3 mm.

Preferably, the first magnetic steel slot further comprises an extension slot which is arranged on one side of the magnetic bridge and extends towards the radial direction of the iron core.

Furthermore, the magnetic steel slot group further comprises two second magnetic steel slots which are distributed in a V shape, the V-shaped tip direction of the second magnetic steel slots faces the center of the iron core, and the second magnetic steel slots are arranged on one side, away from the center of the iron core, of the first magnetic steel slots.

Preferably, the included angle between the two first magnetic steel grooves is smaller than 15 °.

An electric machine comprising said rotor.

Compared with the prior art, the first convex part is arranged in the magnetic steel groove of the rotor core, the first convex part can play a role in guiding, when the motor is in the worst demagnetization state, the first convex part can guide the demagnetization magnetic field, the demagnetization effect of the demagnetization magnetic field on the corner of the magnetic steel is relieved, and meanwhile, the output torque of the motor cannot be influenced.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the embodiments or the prior art descriptions will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without inventive exercise.

FIG. 1 is a schematic diagram of the structure of a magnetic steel slot on an iron core in the invention;

FIG. 2 is a schematic diagram of an enlarged structure of the invention A;

FIG. 3 is a schematic diagram of an enlarged structure of the present invention B.

Detailed Description

In order to make the technical problems, technical solutions and advantageous effects to be solved by the present invention more clearly apparent, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

The rotor comprises an iron core formed by overlapping a plurality of punching sheets, the iron core comprises a plurality of magnetic poles distributed along the circumferential direction of the iron core, and each magnetic pole comprises a magnetic steel slot group.

As shown in fig. 1, one of the magnetic steel slot groups of the iron core is taken as an example for explanation, and the magnetic steel slot group includes two first magnetic steel slots 1 and two second magnetic steel slots 2.

Wherein, two first magnetic steel grooves 1 are V-arrangement symmetric distribution to the most advanced of the V-arrangement that two first magnetic steel grooves 1 constitute extends towards iron core center direction, and the opening is towards the outside of iron core, and two first magnetic steel grooves 1 lie in and form first magnetic bridge 11 between the tip at most advanced, and every is embedded to have a magnet steel 3 in the first magnetic steel groove 1, and magnet steel 3 fixes the middle part position at first magnetic steel groove 1 through sticky mode.

Furthermore, two second magnetic steel grooves 2 are also distributed in a V shape, the second magnetic steel grooves 2 are arranged above the first magnetic steel grooves 1, namely, the second magnetic steel grooves are positioned on the outer side of the radial direction of the first magnetic steel grooves 1, the V-shaped tips formed by the two second magnetic steel grooves 2 extend towards the center direction of the iron core, the openings face the outer side of the iron core, a second magnetic bridge 21 is formed between the end parts of the two second magnetic steel grooves 2 positioned at the tips, magnetic steel 3 is also embedded in each second magnetic steel groove 2, and the magnetic steel 3 is fixed at the middle position of the second magnetic steel groove 2 in an adhesive manner; simultaneously, certain interval has between first magnet steel groove 1 and the second magnet steel groove 2, it is first, the second magnet steel groove all sets up along the quadrature axis magnetic circuit of motor, help reducing the influence of magnet steel groove to motor quadrature axis inductance like this, thereby it is favorable to alleviating the saturation of quadrature axis magnetic circuit to guarantee the reluctance torque of motor, increase reluctance torque's utilization ratio, certain distance also is favorable to alleviating the demagnetization effect of demagnetization magnetic field to the magnet steel between the other two-layer magnet steel.

Preferably, the included angle between the two first magnetic steel grooves 1 is less than 15 degrees, so that the utilization rate of the reluctance torque can be ensured.

Further, the first magnetic steel groove 1 comprises a first groove wall 15 and a second groove wall 16 extending from the tip of the V shape to the opening direction, the first groove wall 15 and the second groove wall 16 are oppositely arranged, wherein the first groove wall 15 is arranged on the inner side of the opening of the V shape, the second groove wall 16 is arranged on the outer side of the opening of the V shape, the magnetic steel 3 is arranged between the first groove wall and the second groove wall in an attaching manner, two side parts of the magnetic steel 3 are attached to the first groove wall 15 and the second groove wall 16, the magnetic steel 3 further comprises a first end part 31 and a second end part 32, the first end part and the second end part are arranged at an included angle with the first magnetic steel and the second magnetic steel, in this embodiment, the first end part 31 is arranged towards the opening direction of the V shape, and the second end part 32 is arranged towards the tip direction of the V shape; and the first magnetic steel slot 1 further comprises a third slot wall 17 arranged on one side of the first magnetic bridge 11, and the third slot wall 17 is arranged towards the radial direction of the iron core.

The utility model provides a set up first convex part 11, second convex part 12 and concave part 13 on the cell wall of first magnet steel groove 1 in this application, but first convex part 11, second convex part 12 and concave part 13 each set up alone the homoenergetic and can play the demagnetization effect of alleviating the demagnetization magnetic field to the magnet steel, also can combine together between two liang or the three in order to play the promotion to 3 anti demagnetization capacities of magnet steel.

Further, as shown in fig. 2, a first protrusion 11 in the present application is disposed at a position close to the first magnetic bridge 11 in the first magnetic steel groove 1, and the first protrusion 11 protrudes toward the inside of the first magnetic steel groove 1, so as to facilitate the mitigation of the demagnetization effect of the demagnetization magnetic field on the magnetic steel.

Preferably, the first protrusion 11 is an arc protrusion, and is disposed at an included angle between the first slot wall 15 and the third slot wall 17, the first protrusion 11 specifically includes three arc segments, which are a first arc segment 111, a second arc segment 112, and a third arc segment 113, the first arc segment 111 is connected to the first slot wall 15 as an arc transition segment, the third arc segment 113 is connected to the third slot wall 17 as a transition segment, and the second arc segment 112 is connected between the first and third arc segments as a protrusion of the first protrusion 11, the first protrusion 11 can perform a flow guiding function, and when the motor is in a worst demagnetization state, the first protrusion 11 can guide a demagnetization field, so as to alleviate a demagnetization effect of the demagnetization field on a corner of the magnetic steel.

Preferably, the maximum distance L1 from the protruding end of the second arc-shaped segment 112 to the third slot wall 17 adjacent to the first magnetic bridge 11 in the present application is 0.6mm to 0.8mm, and the distance H1 from the second arc-shaped segment 112 to the first slot wall 15 is 0.6mm to 0.8 mm; this is because the magnetic steel is weakened in demagnetization resistance by the excessively small H1 and L1, and the magnetic flux leakage is increased by the excessively large H1 and L1, so that the output torque is reduced.

Further, as shown in fig. 3, the second protrusion 12 is disposed on the first groove wall 15, and the second protrusion 12 is disposed at a position close to the first end 31 of the magnetic steel 3, that is, the second protrusion 12 is located at the V-shaped opening of the first magnetic steel groove 1.

Specifically, the second protrusion 12 is also configured as an arc-shaped protrusion, the first magnetic steel groove 1 further includes a fourth groove wall 18 connected to the first groove wall 15, the first groove wall 15 and the magnetic steel 3 are attached to each other for mounting the magnetic steel 3, the fourth groove wall 18 is disposed above the first groove wall 15 (i.e., at the opening end of the V-shape) and has a certain included angle therebetween, and the second protrusion 12 is disposed at an included angle between the first groove wall 15 and the fourth groove wall 18.

The second convex part 12 comprises a fourth arc-shaped section 121 located at the protruding end of the second convex part, and a first straight line section 122 and a second straight line section 123 which are respectively arranged at two ends of the fourth arc-shaped section 121, wherein the first straight line section 122 is connected with the fourth groove wall 18, the joint of the first straight line section 122 and the fourth groove wall 18 is provided with a fillet, the second straight line section 123 is connected with the first groove wall 15, the joint of the second straight line section 123 and the first groove wall 15 is provided with a fillet, the two fillets are arranged to relieve mechanical stress of the rotor in a high-speed state, and.

Preferably, the sizes of the fillets are 0.3mm to 0.5 mm; and the radius R of the fourth arc-shaped segment 121 also takes a value of 0.3mm to 0.5 mm.

Preferably, the protruding height H2 of the second convex portion 12 relative to the first slot wall 15 is 0.15mm to 0.3mm, and the distance between the center of the fourth arc-shaped segment 121 and the first end 31 is 0.9R to 1.1R, and similarly, the values of H2 and L2 are reasonable, so that the second convex portion 12 avoids the influence on the output torque due to the too large H2 and L2, and also ensures that the H2 and L2 are not too small to weaken the demagnetization resistance.

Further, the concave portion 13 is arranged on the first groove wall 15, the concave portion 13 is an arc-shaped notch, the concave portion is close to the corner portion, located at the second end portion 32, of the magnetic steel 3, the arrangement of the concave portion 13 can well inhibit the demagnetization magnetic field from passing through the corner portion of the magnetic steel, and the demagnetization resistance of the magnetic steel 3 is guaranteed.

Preferably, the maximum recess depth H3 of the recess 13 (i.e. the maximum distance between the recess 13 and the first groove wall 15) is 0.3mm to 0.5mm, and the distance between the center of the recess 13 and the second end 32 is 0.1mm to 0.3mm, which ensures that H3 and L3 have good demagnetization resistance and do not affect the output torque of the motor.

Further, first magnet steel slot 1 in this application still is equipped with extending groove 19, extending groove 19 sets up and is located the tip portion that V-arrangement is adjacent with first magnet bridge 11 at first magnet steel slot 1, and extending groove 19 extends certain length from first magnet steel slot 1 radial direction towards the iron core, extending groove 19 is provided with and does benefit to reducing the magnetic leakage, increases the output torque of motor, also makes first magnet bridge 11 elongated simultaneously, also is favorable to alleviating the mechanical stress at this position for the rotor is suitable for high rotational speed and rotates.

Preferably, the second magnetic steel groove 2 may also be provided with an extension groove, and the second magnetic steel groove 2 is provided identically to the extension groove of the first magnetic steel groove 1, which is not described herein again.

Through the experiment, take the magnet steel groove that same quantity and V-arrangement set up, nevertheless the magnet steel demagnetization condition of the different permanent-magnet machine of magnet steel groove inner structure under equal adverse circumstances is as follows:

conventional rotors (without protrusions and recesses): the demagnetization rates of the magnetic steel in the left first magnetic steel groove and the right first magnetic steel groove are respectively 2.33% and 2.37%, and the demagnetization positions of the magnetic steel are mainly concentrated at the corners;

when being equipped with first convex part in the first magnetic steel groove: the demagnetization rates of the magnetic steel in the left first magnetic steel groove and the right first magnetic steel groove are 1.9% and 1.93% respectively, the demagnetization positions are concentrated at the corners, and the demagnetization area is reduced;

when first convex part and second convex part are arranged in first magnetic steel groove: the demagnetization rates of the magnetic steel in the left first magnetic steel groove and the right first magnetic steel groove are 1.44% and 1.4% respectively, the demagnetization positions are concentrated at the corners, and the demagnetization area is further reduced;

when the first magnetic steel groove is provided with the first convex part, the second convex part and the concave part: the demagnetization rates of the magnetic steel in the left first magnetic steel groove and the right first magnetic steel groove are 1.27% and 1.31% respectively, the demagnetization positions are concentrated at the corners, and the demagnetization area reaches the minimum.

The application also provides a motor, and the motor comprises the rotor provided by the application.

Meanwhile, through test comparison, the output conditions of the traditional motor and the motor (provided with the first convex part, the second convex part and the concave part in the first magnetic steel groove) in the application are as follows under the condition that the other conditions are equal: the average value of the torque of the traditional motor is 220.1183Nm, and the torque ripple is 3.69%; the motor of the present application has a mean torque value of 219.7092Nm and a torque ripple of 3.69%.

By last knowing, under the condition that reduces magnet steel demagnetization factor by a wide margin, the output torque of the motor in this application and traditional motor is unchangeable basically, and the output pulsation is unanimous, and the setting of this application has fairly excellent practical value.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.

Claims

1. The utility model provides a rotor, includes iron core and magnet steel slot group, magnet steel slot group includes that two are the V-arrangement and distribute and the most advanced direction of V-arrangement is towards the first magnet steel slot at iron core center, be equipped with the magnet steel in the first magnet steel slot, and two it is the magnetic bridge to lie in V-arrangement point department between the first magnet steel slot, its characterized in that, first magnet steel slot includes: and the first convex part is close to the magnetic bridge and protrudes towards the inside of the first magnetic steel groove.

2. The rotor of claim 1, wherein the first magnetic steel slot comprises a first slot wall and a second slot wall extending from the tip of the V-shape to the opening direction, the magnetic steel is embedded between the first slot wall and the second slot wall, the first slot wall is arranged on the inner side of the V-shape, the magnetic steel comprises a first end part and a second end part arranged at an included angle with the first slot wall, the first end part is arranged towards the opening direction of the V-shape, and the second end part is arranged towards the tip direction of the V-shape;

the first magnetic steel groove further comprises a second convex part which is arranged on the first groove wall and is close to the first end part.

3. The rotor of claim 2, wherein the first magnetic steel slot further comprises a recess opening in the first slot wall proximate the second end.

4. The rotor as claimed in claim 2, wherein the first protrusion is an arc-shaped protrusion, the first protrusion is disposed at the first slot wall and an included angle with the magnetic bridge, a distance H1 from a protruding end of the first protrusion to the first slot wall is 0.6mm to 0.8mm, and a maximum distance L1 from the first protrusion to the magnetic bridge is 0.6mm to 0.8 mm.

5. The rotor as set forth in claim 2 wherein said second lobe is an arcuate lobe having a lobe height H2 of 0.15mm to 0.3mm relative to said first slot wall; the radius of the second convex part is R, and the distance between the circle center of the second convex part and the first end part is 0.9R to 1.1R.

6. The rotor of claim 5, wherein the recess is an arc-shaped notch, the recess has a maximum depression depth H3 of 0.3mm to 0.5mm, and the recess has a center to second end spacing of 0.1mm to 0.3 mm.

7. The rotor of claim 1, wherein the first magnetic steel slot further comprises an extension slot provided at one side of the magnetic bridge and extending toward a radial direction of the core.

8. The rotor as claimed in claim 1, wherein the set of magnetic steel slots further includes two second magnetic steel slots distributed in a V shape with the V-shaped tips facing toward the center of the core, and the second magnetic steel slots are disposed on a side of the first magnetic steel slots away from the center of the core.

9. The rotor of claim 1, wherein an angle between two first magnetic steel slots is less than 15 °.

10. An electrical machine, characterized in that the electrical machine comprises a rotor according to any one of claims 1-9.