CN113972757A

CN113972757A - Permanent magnet motor

Info

Publication number: CN113972757A
Application number: CN202010711567.5A
Authority: CN
Inventors: 殷鹤; 成哲; 钟安解
Original assignee: Jiangmen Xinghong Technology Co ltd
Current assignee: Jiangmen Xinghong Technology Co ltd
Priority date: 2020-07-22
Filing date: 2020-07-22
Publication date: 2022-01-25

Abstract

The application discloses permanent-magnet machine, its stator tooth crown sets up the outer rotor brushless DC motor of 2 supplementary trapezoidal recesses, and this application adds two supplementary trapezoidal recesses that reduce motor starting torque through the lateral surface at every tooth crown, and several supplementary recess and several tooth's socket interval and evenly distributed, and two adjacent supplementary recesses are 8 degrees with the angle that the tooth's socket central line formed. The auxiliary slots increase the total slot number on the stator core by 2 times, so that the electromagnetic vibration generated by the cogging effect of the motor is shifted to high frequency from low frequency, the high frequency vibration replaces the low frequency vibration, the amplitude of the vibration is obviously reduced, and the sound quality of the motor can be improved while the noise is reduced. The auxiliary groove is a trapezoidal groove, so that magnetic saturation caused by grooving is avoided, and magnetic saturation caused by stress concentration is avoided. The invention provides a permanent magnet motor, which weakens the cogging torque of the permanent magnet motor, and has the good performances of stable start, low vibration and low noise.

Description

Permanent magnet motor

Technical Field

The invention belongs to the technical field of motor equipment, and particularly relates to a permanent magnet motor.

Background

The cogging torque is the inherent phenomenon of the permanent magnet motor, it is the torque produced in the circumferential direction by the action of the magnetic field produced by the permanent magnet and the cogging of the armature core under the state of the armature winding is not electrified, it produces the torque produced in the circumferential direction by the action of the permanent magnet and the cogging of the armature core, it produces the tangential force between the permanent magnet and the armature teeth, make the rotor of the permanent magnet motor have a tendency of aligning with the stator along a certain direction, try to position the rotor at certain position, therefore, an oscillating torque produced by the tendency, the cogging torque will make the motor torque fluctuate, produce vibration and noise, the rotating speed fluctuation will appear, make the motor not move smoothly, influence the performance of the motor, make the motor produce undesirable vibration and noise, in the variable speed drive, when the torque ripple frequency is consistent with the mechanical resonance frequency of the stator or the rotor, the vibrations and noise generated by the cogging torque will be amplified and the presence of cogging torque also affects the low speed performance of the motor in the speed control system and the high accuracy positioning in the position control system. Especially at light loads and low speeds. It is important to reduce cogging torque on ceiling fans requiring low speed and smooth operation.

The present invention has been made in view of this situation.

Disclosure of Invention

The technical problem to be solved by the invention is to overcome the defects of the prior art and provide a permanent magnet motor which weakens the tooth space torque of the permanent magnet motor, is stable to start, and has the good performances of low vibration and low noise.

In order to solve the technical problems, the invention adopts the technical scheme that:

a permanent magnet electric machine comprising:

the stator mechanism comprises a shaft core and a stator core arranged on the shaft core;

the stator core comprises a plurality of stator teeth which are distributed at intervals in the circumferential direction, auxiliary grooves are formed in tooth crowns of the stator teeth, and the width of the groove openings of the auxiliary grooves is larger than that of the groove bottoms of the auxiliary grooves.

Further, along the direction from the groove bottom to the groove opening of the auxiliary groove, the auxiliary groove comprises a first section of groove and a second section of groove, and the groove opening of the first section of groove is in smooth transition connection with the groove bottom opening of the second section of groove.

Furthermore, the first section of groove is a rectangular groove, and the second section of groove is a trapezoidal groove.

Furthermore, the notch of the rectangular groove is connected with the notch of the bottom edge of the upper bottom edge of the trapezoidal groove.

In some alternative embodiments, two of said auxiliary slots are provided on the crown of each said stator tooth.

In some optional embodiments, the stator core includes twelve stator teeth, twelve stator teeth are circumferentially and uniformly distributed at intervals, two auxiliary slots are provided on a crown of each stator tooth, and an included angle between a center of each auxiliary slot and a line connecting axes of the shaft cores is eight degrees.

Further, the method also comprises the following steps: the rotor mechanism comprises a rotor assembly and a cover body, the rotor assembly comprises a casing, the casing is provided with a positioning portion, the cover body is provided with a matching portion, and the casing and the cover body are matched and positioned to be connected through the positioning portion and the matching portion.

Further, the rotor subassembly includes fourteen magnet steel and fixed bolster, fourteen the even interval distribution in magnet steel circumference sets up on the casing inner wall, the fixed bolster sets up on the casing inner wall, the restriction the magnet steel removes.

In some alternative embodiments, the shaft core is provided with a first bearing and a second bearing on both sides of the stator core, the housing is recessed to form a first bearing chamber for accommodating the first bearing, and the cover is recessed to form a second bearing chamber for accommodating the second bearing.

In some optional embodiments, the cover body is provided with reinforcing ribs circumferentially and uniformly distributed at intervals. After the technical scheme is adopted, compared with the prior art, the invention has the following beneficial effects.

According to the permanent magnet motor provided by the invention, the auxiliary groove is arranged on the tooth crown of the stator tooth, and the width of the notch of the auxiliary groove is larger than that of the groove bottom of the auxiliary groove, so that the tooth space torque of the permanent magnet motor can be weakened, the starting torque of the permanent magnet motor is reduced, the difficulty in starting the permanent magnet motor is avoided, and the permanent magnet motor vibrates during running, so that the permanent magnet motor can be stably started, and has the good performances of low vibration and low noise.

The following describes embodiments of the present invention in further detail with reference to the accompanying drawings.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention, are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the invention without limiting the invention to the right. It is obvious that the drawings in the following description are only some embodiments, and that for a person skilled in the art, other drawings can be derived from them without inventive effort. In the drawings:

fig. 1 is a schematic overall structure diagram of a permanent magnet motor provided by the present invention;

FIG. 2 is a schematic view of the overall structure of the stator mechanism provided by the present invention;

FIG. 3 is a schematic view of a stator core construction provided by the present invention;

FIG. 4 is a schematic view of a stator tooth configuration provided by the present invention;

FIG. 5 is a schematic view of a rotor assembly structure provided by the present invention;

fig. 6 is a schematic view of a cover structure provided in the present invention.

In the figure: 1. a stator mechanism; 2. a rotor mechanism; 3. a first bearing; 4. a second bearing; 5. a stator core; 6. stator teeth; 7. a crown; 8. an auxiliary groove; 9. a first section of groove; 10. a second section of groove; 11. a cover body; 12. a fitting portion; 13. a second bearing chamber; 14. reinforcing ribs; 15. a second bolt hole; 16. a housing; 17. a first bolt hole; 18. a positioning part; 19. magnetic steel; 20. fixing a bracket; 21. a first bearing chamber; 22. and (4) a shaft core.

It should be noted that the drawings and the description are not intended to limit the scope of the inventive concept in any way, but to illustrate it by a person skilled in the art with reference to specific embodiments.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and the following embodiments are used for illustrating the present invention and are not intended to limit the scope of the present invention.

In the description of the present invention, it should be noted that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "inner", "outer", etc., indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; may be directly connected or indirectly connected through an intermediate. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

As shown in fig. 1 to 6, the permanent magnet motor provided by the present invention includes a stator mechanism 1, the stator mechanism 1 includes an axis core 22 and a stator core 5 disposed on the axis core 22, the stator core 5 includes a plurality of stator teeth 6 circumferentially distributed at intervals, an auxiliary groove 8 is disposed on a crown 7 of the stator teeth 6, and a width of a notch of the auxiliary groove 8 is greater than a width of a bottom of the auxiliary groove 8.

According to the permanent magnet motor provided by the invention, the tooth crown 7 of the stator tooth 6 is provided with the auxiliary groove 8, and the width of the notch of the auxiliary groove 8 is larger than the width of the groove bottom of the auxiliary groove 8, so that the tooth space torque of the permanent magnet motor can be weakened, the starting torque of the permanent magnet motor is reduced, the difficulty in starting the permanent magnet motor is avoided, and the vibration is generated during the operation, so that the good performances of stable starting, low vibration and low noise of the permanent magnet motor are realized.

Further, in the direction from the groove bottom to the notch of the auxiliary groove 8, the auxiliary groove 8 comprises a first section groove 9 and a second section groove 10, and the notch of the first section groove 9 is in smooth transition connection with the groove bottom of the second section groove 10.

The auxiliary groove 8 comprises a first section groove 9 and a second section groove 10 which are communicated, the width of the second section groove 10 is larger than that of the first section groove 9, and the notch of the first section groove 9 is in smooth transition connection with the notch of the second section groove 10.

The slot width of the second section of slot 10 is larger than that of the auxiliary slot 8 of the first section of slot 9, so that the cogging torque of the permanent magnet motor can be better weakened, the permanent magnet motor can be started stably, and the permanent magnet motor has good performances of low vibration and low noise.

Further, the first section of groove 9 is a rectangular groove, and the second section of groove 10 is a trapezoidal groove.

Specifically, the first groove 9 is a rectangular groove, and the second groove 10 is a trapezoidal groove. The first section of groove 9 is a rectangular groove, and the second section of groove 10 is an auxiliary groove 8 formed by a trapezoidal groove, so that the processing and manufacturing are convenient, and the stress concentration during processing is avoided.

Be the rectangular channel by first section groove 9, the auxiliary tank 8 that second section groove 10 formed for trapezoidal channel, because second section groove 10 can avoid appearing the closed angle for the trapezoidal channel, avoid adding the stress concentration that appears man-hour, avoid stator mechanism 1 to appear magnetic saturation.

As shown in fig. 1 to 6, in some alternative embodiments, two auxiliary grooves 8 are provided on the crown 7 of each stator tooth 6.

In particular, two auxiliary grooves 8 are provided on the crown 7 of each stator tooth 6. The auxiliary slots 8 increase the total slot number on the stator core 5 by 2 times, and for fractional slot windings, the electromagnetic vibration generated between the magnetic pole of the rotor mechanism 2 of the permanent magnet motor and the stator teeth 6 of the stator mechanism 1 due to the cogging effect moves to high frequency from low frequency, so that the high frequency vibration replaces the low frequency vibration, the amplitude of the vibration is obviously reduced, and the motor sound quality can be improved while the noise is reduced.

As shown in fig. 1 to 6, in some alternative embodiments, the stator core 5 includes twelve stator teeth 6, the twelve stator teeth 6 are circumferentially and uniformly distributed at intervals, two auxiliary slots 8 are provided on the crown 7 of each stator tooth 6, and an included angle between the centers of the two auxiliary slots 8 and a line connecting the axes of the shaft cores 22 is eight degrees.

The permanent magnet motor further comprises a rotor mechanism 2, the rotor mechanism 2 comprises a rotor assembly and a cover body 11, the rotor assembly comprises a casing 16, the casing 16 is provided with a positioning part 18, the cover body 11 is provided with a matching part 12, and the casing 16 and the cover body 11 are mutually matched, positioned and connected through the positioning part 18 and the matching part 12.

Further, the rotor subassembly includes fourteen magnet steel 19 and fixed bolster 20, and fourteen magnet steel 19 circumference evenly spaced apart sets up on the 16 inner walls of casing, and fixed bolster 20 sets up on the 16 inner walls of casing, restriction magnet steel 19 removes.

Further, on both sides of the stator core 5, the shaft core 22 is provided with the first bearing 3 and the second bearing 4, the housing 16 is recessed to form a first bearing chamber 21 for accommodating the first bearing 3, and the cover 11 is recessed to form a second bearing chamber 13 for accommodating the second bearing 4.

Specifically, the present invention provides a permanent magnet motor, which is exemplified by a 14-pole 12-slot single-phase outer rotor permanent magnet motor. The stator mechanism 1 comprises an axial core 22 and a stator core 5 arranged on the axial core 22, wherein a first bearing 3 and a second bearing 4 are arranged on the axial core 22 at two sides of the stator core 5, the stator core 5 comprises twelve stator teeth 6, the twelve stator teeth 6 are circumferentially distributed at equal intervals, a stator slot is formed between every two adjacent stator teeth 6, and a winding is arranged in the stator slot and wound around the teeth of the stator core 5.

Two auxiliary grooves 8 are arranged on a tooth crown 7 of each stator tooth 6, the included angle between the centers of the two auxiliary grooves 8 and the axis connecting line of the shaft core 22 is eight degrees, the auxiliary grooves 8 increase the total number of the grooves on the stator core 5 by 2 times, and for fractional groove windings, the electromagnetic vibration generated between the magnetic pole of the rotor mechanism 2 of the permanent magnet motor and the stator teeth 6 of the stator mechanism 1 due to the tooth space effect is moved to high frequency from low frequency, so that the high frequency vibration replaces the low frequency vibration, the vibration amplitude is obviously reduced, and the motor sound quality can be improved while the noise is reduced.

The auxiliary groove 8 comprises a first section groove 9 and a second section groove 10 along the groove bottom to notch direction of the auxiliary groove 8, and the notch of the first section groove 9 is smoothly transited and connected with the groove bottom of the second section groove 10. The first section of groove 9 is a rectangular groove, and the second section of groove 10 is a trapezoidal groove. The notch of the rectangular groove is connected with the bottom notch of the upper bottom edge of the trapezoidal groove.

In detail, the width of the lower bottom edge notch of the second section of groove 10, which is a trapezoidal groove, is 3mm, the width of the upper bottom edge notch of the trapezoidal groove is 2.5mm, and the depth of the second section of groove 10, which is a trapezoidal groove, is 0.6 mm. The width of the first section of groove 9, which is a rectangular groove, is 2.5mm, and the depth of the first section of groove 9, which is a rectangular groove, is 0.6 mm.

It should be noted that the specific size of the second-stage groove 10 and the specific size of the first-stage groove 9 can be set by those skilled in the art according to actual needs.

Rotor mechanism 2 includes rotor subassembly and lid 11, and the rotor subassembly includes fourteen pieces of magnet steel 19 and fixed bolster 20, and fourteen pieces of magnet steel 19 even interval distribution in circumference set up on casing 16 inner wall, and magnet steel 19 passes through glue and casing 16 inner wall fixed connection, and fixed bolster 20 sets up on casing 16 inner wall, and restriction magnet steel 19 removes. The fourteen magnetic steels 19 are spaced by the fixing bracket 20, and it is ensured that each magnetic steel 19 does not move when the rotor mechanism 2 rotates at a high speed.

The rotor assembly comprises a machine shell 16, wherein the machine shell 16 is provided with a positioning part 18, the cover body 11 is provided with a matching part 12, and the machine shell 16 and the cover body 11 are mutually matched and positioned and connected through the positioning part 18 and the matching part 12.

Specifically, the casing 16 is provided with a positioning portion 18, the positioning portion 18 is a positioning arc, the cover 11 is provided with a matching portion 12, the matching portion 12 is an arc notch, and the casing 16 and the cover 11 are mutually matched and positioned and connected through the positioning arc and the arc notch.

Furthermore, four positioning arcs are uniformly distributed in the circumferential direction of the casing 16 at intervals, four arc notches are uniformly distributed in the circumferential direction of the cover 11 at intervals, and the four positioning arcs of the casing 16 are matched with the four arc notches of the cover 11 to realize the positioning connection of the casing 16 and the cover 11. After positioning connection, four first bolt holes 17 are uniformly distributed in the circumferential direction of the casing 16 at intervals, four second bolt holes 15 are uniformly distributed in the circumferential direction of the cover 11 at intervals, and the casing 16 and the cover 11 are fixedly connected by the four bolts correspondingly penetrating through the first bolt holes 17 of the casing 16 and the second bolt holes 15 of the cover 11.

The housing 16 is recessed to form a first bearing chamber 21 for accommodating the first bearing 3, and the cover 11 is recessed to form a second bearing chamber 13 for accommodating the second bearing 4.

The first bearing 3 and the second bearing 4 provided on the shaft core 22 are respectively installed in a first bearing chamber 21 recessed in the housing 16 to accommodate the first bearing 3 and a second bearing chamber 13 recessed in the cover 11 to accommodate the second bearing 4. The rotor mechanism 2 is rotatably connected with the stator mechanism 1 through a first bearing 3 and a second bearing 4.

Further, the cover 11 is provided with ribs 14 circumferentially and uniformly spaced. The rotor mechanism 2 is ensured not to be deformed or twisted when rotating at a high speed, and the stability of the rotor mechanism 2 when rotating at a high speed is ensured.

Further, the permanent magnet motor also includes concentrated windings wound around the stator teeth 6. Because the end connection part of the concentrated winding is shorter, the using amount of the conducting wire is less, the resistance and copper consumption of the winding coil are reduced, and the running efficiency of the permanent magnet motor is improved.

Foretell permanent-magnet machine is provided with auxiliary groove 8 on the crown 7 of stator tooth 6 to the width of the notch of auxiliary groove 8 is greater than the width of the tank bottom of auxiliary groove 8, proves through the experiment with the actual operation on, can weaken permanent-magnet machine tooth's socket moment of torsion, reduces permanent-magnet machine starting torque, has avoided permanent-magnet machine to start the difficulty, the vibration appears in the operation, thereby realizes permanent-magnet machine smooth start, the good performance of low vibration nature, low noise.

Although the present invention has been described with reference to a preferred embodiment, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims

1. A permanent magnet electric machine, comprising:

2. The permanent magnet electric machine of claim 1 wherein the auxiliary slots comprise a first segment slot and a second segment slot in a slot bottom to slot bottom direction, the slot bottom of the first segment slot being in smooth transition connection with the slot bottom mouth of the second segment slot.

3. The permanent magnet electric machine of claim 2 wherein the first segment of slots are rectangular slots and the second segment of slots are trapezoidal slots.

4. The permanent magnet electric machine of claim 3 wherein the notch of the rectangular slot is connected to the bottom notch of the upper bottom edge of the trapezoidal slot.

5. A permanent magnet electric machine according to claim 1, characterized in that two auxiliary slots are provided on the crown of each stator tooth.

6. The permanent magnet motor according to any one of claims 1 to 5, wherein the stator core comprises twelve stator teeth, twelve stator teeth are circumferentially and uniformly distributed at intervals, two auxiliary slots are arranged on a crown of each stator tooth, and an included angle between centers of the two auxiliary slots and a line connecting axes of the shaft cores is eight degrees.

7. The permanent magnet electric machine of claim 6, further comprising: the rotor mechanism comprises a rotor assembly and a cover body, the rotor assembly comprises a casing, the casing is provided with a positioning portion, the cover body is provided with a matching portion, and the casing and the cover body are matched and positioned to be connected through the positioning portion and the matching portion.

8. The permanent magnet motor according to claim 7, wherein the rotor assembly comprises fourteen magnetic steels and a fixing bracket, the fourteen magnetic steels are circumferentially and uniformly distributed on the inner wall of the casing at intervals, and the fixing bracket is arranged on the inner wall of the casing to limit the movement of the magnetic steels.

9. The permanent magnet electric machine of claim 7 wherein the shaft core is provided with a first bearing and a second bearing on either side of the stator core, the housing being recessed to form a first bearing chamber for receiving the first bearing, and the cover being recessed to form a second bearing chamber for receiving the second bearing.

10. The permanent magnet motor of claim 7, wherein the cover body is provided with reinforcing ribs circumferentially and uniformly spaced.