CN113346643A

CN113346643A - Permanent magnet motor

Info

Publication number: CN113346643A
Application number: CN202110809097.0A
Authority: CN
Inventors: 李文瑞; 李虎; 甘峰; 于明湖; 迟闯
Original assignee: Guangdong Welling Motor Manufacturing Co Ltd
Current assignee: Guangdong Welling Motor Manufacturing Co Ltd
Priority date: 2018-05-31
Filing date: 2018-11-30
Publication date: 2021-09-03
Also published as: CN110556939A; CN108923553A; CN209250350U; CN113346644A; CN110556939B

Abstract

The invention relates to the field of permanent magnet motors, and discloses a permanent magnet motor, comprising a casing, a stator iron core and a rotor iron core; the stator iron core is circumferentially arranged along the inner wall of the casing, and the rotor iron core is installed in the space enclosed by the stator core; the rotor core includes at least two fully connected bridge lamination sets and at least one semi-connected bridge lamination set, wherein the fully connected bridge lamination set is The laminations include a plurality of full bridge punches that are connected to the first central connecting bridge and distributed along the circumferential direction, and the laminations in the semi-connecting bridge lamination group include at least one that is disconnected from the second central connecting bridge And the separated punching sheets are distributed along the circumferential direction, and the fully-connected bridge-type lamination group and the half-connected bridge-type lamination group are axially stacked so that each half-connected bridge-type lamination group is located at two between the fully connected bridge lamination sets, so that the adjacent sectors of the rotor core are asymmetrical. The present invention can improve the power density of the motor.

Description

Permanent magnet motor

The application is a divisional application with the application date of '2018.11.30', the application number of '201811459899.8' and the application name of 'a high-power density permanent magnet motor'.

Technical Field

The invention relates to the field of permanent magnet motors, in particular to a permanent magnet motor.

Background

The traditional brushless direct current motor adopts a surface-mounted magnetic shoe or a built-in radial magnetizing magnetic steel structure, has low power density and is limited to cost factors, and the magnetic flux of each pole of the motor is improved by a tangential magnetizing parallel magnetic circuit structure. The existing tangential magnetizing structure still has the problem of large magnetic flux leakage, and the performance improvement of the motor is limited.

Patent CN201611226568.0 discloses a rotor core having at least one tooth sector disconnected from the rotor collar, while at least one tooth sector is connected to the shaft collar. Thereby suppressing leakage flux at the paraxial region. A positioning convex part is arranged outside the lantern ring of the rotating shaft of the rotor core and used for positioning and supporting the permanent magnet. Through the analysis, because tooth portion sector axial of this scheme rotor disconnection does not have fixed support component, axial structure intensity is relatively poor, is unfavorable for large-scale production, and simultaneously, foretell location arch for supporting and fixing a position the permanent magnet will produce from the interlinkage magnetic leakage, reduces motor power density, is unfavorable for promoting the performance.

On the other hand, the built-in tangential magnetizing motor has the advantages that due to the improvement of power density, a stator core is easy to saturate to generate higher core loss, and the motor efficiency is reduced. While the electromagnetic wave enhancement results in an increase in vibration noise. In the prior art, vibration noise is suppressed by methods such as a skewed pole chute, the manufacturing process difficulty is increased and the production man-hour is increased by corresponding methods, a bar-shaped stator core with a bent circle is designed in patent CN201320738896.4, tooth parts are inwards extended from an annular yoke part of a stator, and a slot inserting groove is formed between two adjacent stator tooth parts. The stator has balanced magnetic circuit, moderate and average magnetic density, reduced local saturation, simple process and high production efficiency. However, the above patent only depends on parameters such as stator slot width, tooth width and yoke width to perform average processing on magnetic density, and fails to consider the influence of stator shape and structure on motor magnetic field, loss and the like, and is not applicable to high power density motor structure, and does not provide a structure capable of comprehensively considering power density and suppressing vibration and reducing noise in order to consider reducing motor vibration noise by a combination method between a stator core and a casing.

Therefore, there is a need for a permanent magnet brushless dc motor with simple process, reliable structure, high power density and low vibration noise, which is suitable for mass production and manufacturing.

Disclosure of Invention

In order to overcome the defects in the prior art, the invention aims to provide a permanent magnet motor which can simplify the production process and improve the structural strength and the power density.

In order to solve the technical problem, the invention provides a permanent magnet motor, which comprises a casing, a stator core and a rotor core; the stator iron cores are distributed along the circumferential direction of the inner wall of the shell, and the asymmetric mixed rotor iron cores are arranged in a space surrounded by the stator iron cores; the rotor core comprises at least two full bridge type lamination groups and at least one half bridge type lamination group, wherein the lamination in the full bridge type lamination group comprises a first center connecting bridge and a plurality of full bridge type lamination sheets which are connected with the first center connecting bridge and distributed along the circumferential direction, the lamination in the half bridge type lamination group comprises a second center connecting bridge and at least one separating lamination sheet which is disconnected with the second center connecting bridge and distributed along the circumferential direction, and the full bridge type lamination group and the half bridge type lamination group are stacked along the axial direction to form each half bridge type lamination group is positioned between the two full bridge type lamination groups so as to enable adjacent sectors of the rotor core to be asymmetric.

Preferably, the fully-bridged lamination set comprises a plurality of fully-bridged laminations, and adjacent fully-bridged laminations are overlapped and stacked; the half-bridge type lamination group comprises a plurality of half-bridge type laminations, and the adjacent half-bridge type laminations are overlapped and stacked.

Preferably, the stator core is enclosed by a plurality of T-shaped tooth connecting yokes, the outer surface of each T-shaped tooth connecting yoke is parallel to the bottom of the stator slot, the boundary surfaces of the tooth parts of the T-shaped tooth connecting yokes and the yoke parts are perpendicular, and the number of the T-shaped tooth connecting yokes is equal to the number of the motor slots.

Preferably, each T-shaped tooth connecting yoke is provided with two inner and outer riveting points with different sizes, and the diameter of the outer riveting point is larger than that of the inner riveting point.

Preferably, the outer boundary of the stator core is in a regular polygon structure; the stator core and the shell are contacted at the connecting point of each T-shaped tooth connecting yoke to form a contact area, and a gap, which is not contacted with the shell, of the stator core forms a filling area by injecting a filling material.

Preferably, the full bridge type lamination comprises a plurality of full bridge stamped sheets, and a supporting bridge is arranged between every two adjacent full bridge stamped sheets; in two adjacent full bridge punching sheets, one of the two full bridge punching sheets protrudes outwards along the radial direction to form a wide magnetic bridge, the other one protrudes outwards along the radial direction to form a narrow magnetic bridge, and the width of the wide magnetic bridge is larger than that of the narrow magnetic bridge.

Preferably, the half-bridge type lamination comprises a plurality of half-bridge stamped sheets and a plurality of separated stamped sheets, one separated stamped sheet is arranged between every two adjacent half-bridge stamped sheets, and the separated stamped sheets are not in contact with the half-bridge stamped sheets; a partition type supporting bridge is arranged between every two half-bridge punching sheets; the semi-bridge punching sheet is provided with a narrow magnetic bridge, the first central connecting bridge is provided with an isolating type wide magnetic bridge, and the width of the isolating type wide magnetic bridge is larger than that of the narrow magnetic bridge.

Preferably, in at least one of the laminated layers, adjacent ones of the wide and narrow magnetic bridges have different lengths, each extending radially outward to form a first sector.

Preferably, permanent magnets are placed in the slots between the adjacent sectors, the polarities of the permanent magnets in the two adjacent slots are different, and the corresponding first central connecting bridge in the slot protrudes outwards in the radial direction to form the supporting bridge; the support bridge is in contact with the permanent magnet.

Preferably, within at least one of the laminations, the second central connecting bridge extends radially outwardly to form the narrow magnetic bridge;

each narrow magnetic bridge extends outwards along the radial direction to form a second sector; the narrow magnetic bridge is connected with the second sector, and the partition type wide magnetic bridge is disconnected with the second sector.

Preferably, the areas of two adjacent second sectors are not equal.

Preferably, permanent magnets are placed in the slots between the adjacent second sectors, the polarities of the permanent magnets in the two adjacent slots are different, and the corresponding second central connecting bridges in the slots extend outwards in the radial direction to form slot bottom protrusions; the groove bottom protrusion is spaced from the permanent magnet.

Preferably, the outer arc surface of each full bridge sheet comprises a plurality of sections of splines for reducing torque fluctuation; the splines at least comprise main splines of the circular arc section and straight-line splines which are respectively arranged on two sides of the main splines of the circular arc section.

Preferably, the splines comprise a main spline of a circular arc segment, splines of circular arc segments respectively arranged at two sides of the main spline of the circular arc segment, and straight-line splines respectively arranged at the outer sides of the two splines of the circular arc segment.

Preferably, the outer circular arc surface of each half-bridge stamped piece and each separating stamped piece comprises a plurality of sections of splines for reducing torque fluctuation; the splines at least comprise main splines of the circular arc section and straight-line splines which are respectively arranged on two sides of the main splines of the circular arc section; preferably, the splines comprise a main spline of a circular arc segment, splines of circular arc segments respectively arranged at two sides of the main spline of the circular arc segment, and straight-line splines respectively arranged at the outer sides of the two splines of the circular arc segment.

The invention can simplify the production process of the motor and improve the structural strength of the motor. Through designing partition type supporting bridge and partition type wide magnetic bridge, the structural strength of the motor rotor is greatly improved. Meanwhile, the semi-bridge type lamination ensures that at least half of sectors of one lamination of the rotor core can be connected with the shaft sleeve, and the positioning is easy in the large-scale production process.

The invention can greatly reduce the self-interlinkage magnetic leakage at the bottom of the rotor slot, thereby improving the air gap magnetic flux, and can reduce the saturation degree of the motor and maximize the magnetic flux of each pole through the T-shaped tooth connecting yoke stator structure. Compared with the counter electromotive force coefficient of the traditional motor structure in full-bridge connection, the counter electromotive force coefficient of the motor adopting the structure is obviously improved, and when the motor runs under heavy load, the torque-current curve linearity of the motor is good, and the saturation phenomenon does not occur, so that the motor performance is improved.

Through the rotor five-segment spline structure, the counter potential harmonic distortion rate of the motor is low, and the sine degree of an air gap magnetic field is good, so that the tangential torque pulsation and radial vibration of the motor are reduced. Meanwhile, a T-shaped tooth yoke structure is adopted, and a filling area is arranged between the stator and the machine shell, so that the transmission of vibration between the stator and the machine shell is weakened, and the vibration reduction and noise reduction of the motor are realized.

The rotor slot bottom self-crosslinking magnetic leakage is reduced, so that the power density is improved, the high sine of an air gap magnetic field can be ensured, and the counter potential coefficient is greatly improved. The invention can simplify the production process of the motor and improve the structural strength of the motor. The motor structure shows that the self-crosslinking flux leakage at the bottom of the rotor slot is reduced, so that the power density is improved, the high sine of an air gap magnetic field can be ensured, and the counter potential coefficient is greatly improved.

Drawings

FIG. 1 is a schematic block diagram of one embodiment of the present invention;

FIG. 2 is a schematic view of a rotor core according to an embodiment of the present invention;

FIG. 3 is a schematic view of a T-tooth yoke according to an embodiment of the present invention;

FIG. 4 is a schematic view of a stator assembly according to an embodiment of the present invention;

FIG. 5 is a schematic structural view of a half-bridge laminate in accordance with an embodiment of the present invention;

FIG. 6 is a schematic structural view of a fully bridged lamination in accordance with an embodiment of the present invention;

FIG. 7(a) is a prior art full-bridge connected rotor slot bottom self-crosslinking magnetic flux leakage distribution;

FIG. 7(b) is an enlarged partial view of the circled portion of the block in FIG. 7 (a);

FIG. 8(a) is the distribution of the self-interlinking leakage flux at the bottom of the bridge rotor slot without the partition support in the prior art;

FIG. 8(b) is an enlarged partial view of the circled portion of the block in FIG. 8 (a);

FIG. 9(a) is the self-interlinking leakage distribution of the bottom of the isolated support bridge rotor slot of the present invention;

FIG. 9(b) is an enlarged partial view of the circled portion of the block in FIG. 9 (a);

FIG. 10 is a comparison curve of the leakage coefficients of the self-interlinking slot bottoms at the paraxial positions of three motors with different structures;

FIG. 11 is a schematic view of the space within the regular polygon T-shaped tooth yoke stator slots in accordance with an embodiment of the present invention;

FIG. 12 is a schematic view of the space within a stator slot of a conventional construction;

FIG. 13 is a schematic view of the distribution of the splines of a five-spline rotor segment in accordance with an embodiment of the present invention;

FIG. 14 is the no-load back emf harmonic content of one embodiment of the present invention;

FIG. 15 is an exploded view of a rotor core according to an embodiment of the present invention;

figure 16 is a schematic view of a half-bridged lamination stack in accordance with an embodiment of the present invention.

Description of the reference numerals

A housing 1;

a stator core 2; a contact field 22; a fill field 23;

a T-shaped tooth yoke 21; a yoke portion 211; stator slot bottom 2111; a bending point 2112; a tooth portion 212; a sloping shoulder crown groove 2121; outer rivet points 213; inner rivet points 214;

a rotor core 3;

a full bridge lamination stack 31; a full bridge sheet 311; outer arcuate surface 3111; plastic-coated through holes 3112; rivet point 3113; a first central connecting bridge H1; a support bridge 312; a wide magnetic bridge 313; a narrow magnetic bridge 314;

half-bridge lamination stack 32; a half-bridge punch 321; an outer circular arc surface 3211 of the half-bridge stamped piece; a plastic-coated through hole 3212 of the half-bridge punching sheet; a riveting point 3213 of the half-bridge stamped piece; a separation punch 322; an outer arc surface 3221 of the separation punch; a plastic-coated through hole 3222 of the punching sheet is separated; rivet points 3223 of the punching sheets are separated; a second central connecting bridge H2; a partitioned support bridge 323; a partitioned wide magnetic bridge 324; a narrow magnetic bridge 325;

a permanent magnet 4; a shaft 5; a winding 6; an insulating frame 7.

Detailed Description

The following detailed description of embodiments of the invention refers to the accompanying drawings. It should be understood that the detailed description and specific examples, while indicating the present invention, are given by way of illustration and explanation only, not limitation.

It should be mentioned in advance that in the description of the present application, "axial direction" generally refers to the axial direction of the electric machine, i.e. the direction of extension along the axis of rotation of the electric machine.

As shown in fig. 1, one embodiment of the present invention is a permanent magnet brushless dc motor including a housing 1, a stator core 2, a rotor core 3, a permanent magnet 4, a shaft 5, a winding 6, and an insulating frame 7.

As shown in fig. 3 and 4, the stator core 2 is formed by enclosing 12T-shaped tooth connecting yokes 21, the stator core 2 and the casing 1 are in contact through the connecting points between the adjacent T-shaped tooth connecting yokes 21, the contact portion forms a contact area 22, the outer surface or the top surface of the yoke portion 211 of each T-shaped tooth connecting yoke 21 is a plane, a gap between the yoke portion and the inner wall of the circular casing 1 forms a filling area 23, and the filling area 23 can be filled with a plurality of materials. The winding 6 adopts flying fork winding, and the designed stator slot type can effectively avoid the interference of flying fork winding and improve the mass production efficiency.

As shown in fig. 3, the outer surface of the yoke portion 211 of the T-shaped tooth yoke 21 is parallel to the stator slot bottom 2111, the T-shaped tooth yoke 21 is provided with two riveting points with different sizes, the outer riveting point 213 is larger than the inner riveting point 214 in size, in this embodiment, the diameter of the outer riveting point 213 is 1.2mm, and the diameter of the inner riveting point 214 is 1.0 mm; the outer riveting point 213 is arranged at the center of the yoke 211, and the inner riveting point 214 is arranged in the middle of the tooth crown of the tooth part 212; in the present embodiment, as shown in fig. 11, the theoretical winding slot area of the stator core 2 is increased by 8.5% compared with the winding slot area of the conventional circular stator core stamped piece shown in fig. 12, in comparison with the winding slot area of the conventional circular stator core stamped piece shown in fig. 12, in which the crown shape of the tooth portion 212 is a sloping surface, an included angle between an inner slope of the sloping-shoulder crown slot 2121 and a radial boundary of the tooth portion 212 is an obtuse angle, preferably 120 °, the tooth portion 212 is perpendicular to an outer surface of the yoke portion 211 or a stator slot bottom 2111, a slope of a straight line segment of the sloping-shoulder crown slot 2121 is 30 °, a width of a narrowest point of the tooth portion 212 is 5.2mm, and a height of the yoke portion 211 is 3.5 mm. The bending point 2112 mainly functions to release stress for the stator core 2 to perform rounding.

As shown in fig. 2, 15 and 16, in the present embodiment, the rotor core 3 includes two full-bridge type lamination sets 31 and one half-bridge type lamination set 32, and the half-bridge type lamination set 32 is located between the two full-bridge type lamination sets 31 in the axial stacking manner, that is, the two full-bridge type lamination sets 31 are respectively located at two ends of the rotor core 3, and the half-bridge type lamination set 32 is located in the middle of the rotor core 3, so that the structure of the rotor core can make adjacent sectors asymmetrical, thereby greatly reducing the self-interlinkage magnetic leakage of the permanent magnet slot bottom at the near axis to improve the power density.

The half-bridge type lamination group 32 is formed by stacking a plurality of half-bridge type laminations as shown in fig. 5, each half-bridge type lamination comprises a plurality of half-bridge punching sheets 321 and a plurality of separation punching sheets 322, a separation punching sheet 322 is arranged between every two adjacent half-bridge punching sheets 321, and the separation punching sheets 322 are not in contact with the half-bridge punching sheets 321; a partition type supporting bridge 323 is arranged between every two half-bridge punching sheets 321; the half-bridge punching sheet 321 is provided with a narrow magnetic bridge 325, the first central connecting bridge H1 is provided with an isolating wide magnetic bridge 324, and the width of the isolating wide magnetic bridge 324 is greater than that of the narrow magnetic bridge 325.

The full bridge type lamination stack 31 is formed by stacking full bridge type laminations as shown in fig. 6, and the full bridge type laminations comprise a plurality of full bridge stamped sheets 311 with supporting bridges 312 between adjacent sheets; in two adjacent full bridge punching sheets 311, one of the two full bridge punching sheets protrudes outwards along the radial direction to form a wide magnetic bridge 313, the other one protrudes outwards along the radial direction to form a narrow magnetic bridge 314, the width of the wide magnetic bridge 313 is larger than that of the narrow magnetic bridge 314, a plastic-coated through hole 3112 is axially arranged on the full bridge type lamination sheet, a plastic-coated through hole 3212 is axially arranged on the half bridge type lamination sheet, plastic materials are adopted to wrap and reinforce the rotor core 3 through the through of the plastic-coated through holes 3112 and 3212, the through holes are positioned and connected through riveting points 3113, 3213 and 3223, the distance between the edge of the through hole of the punching sheet and the boundary of the adjacent permanent magnet groove is 2.6mm, the axial stacking structure is A + B + A, a group of full bridge type lamination sheets 31 comprises 10 full bridge type lamination sheets, a group of half bridge type lamination sheets 32 comprises 30 half bridge type lamination sheets, the back emf coefficient of the motor of this embodiment is improved by 34.4% compared to a motor in which the rotor is formed entirely of half-bridge laminations.

As shown in fig. 6, the full bridge type lamination is a full bridge type structure, wherein 10 full bridge stampings 311 included therein are connected into a whole through a first central connecting bridge H1, the first central connecting bridge H1 includes a plurality of supporting bridges 312, a plurality of wide magnetic bridges 313 and a plurality of narrow magnetic bridges 314, and the first central connecting bridge H1 is a continuous whole. The thickness of the permanent magnet 4 selected in the embodiment is 5mm, the width of the narrow magnetic bridge 314 is 0.8mm, the width of the wide magnetic bridge 313 is 1.5mm, the length of the magnetic bridge is 2.8mm, and the width of the supporting bridge 312 is 1.2 mm.

As shown in fig. 5, the half-bridge type lamination is a half-bridge type structure, wherein the included 5 separation punching sheets 322 are all disconnected from the second central connection bridge H2, that is, the 5 separation punching sheets 322 are not connected to the second central connection bridge H2, and are in a separated state from the second central connection bridge H2, the second central connection bridge H2 includes a plurality of partitioned support bridges 323, a plurality of partitioned wide magnetic bridges 324, and a plurality of narrow magnetic bridges 325, and the second central connection bridge H2 is a continuous whole. Of course, the number of the separating sheets 322 is not limited to 5, and may be 1 to 4, or may be other numbers. The width of the narrow magnetic bridge 325 is 0.8mm, the distance between the partition type supporting bridge 323 and the permanent magnet 4 is 2.5mm, through optimization of the parameters, the magnetic leakage of the bottom of the permanent magnet groove at the position close to the axis of the rotor core 3 is greatly reduced, other parameters are guaranteed to be unchanged, the bottom of the groove of the motor with the three structures of the full-bridge connection type rotor structure, the non-partition supporting bridge type structure and the magnetic field distribution of the embodiment are respectively compared, and the magnetic leakage coefficient of the self-cross-link groove is calculated, and referring to fig. 10, the bottom of the groove of the motor with the three structures of the full-bridge connection type A, the non-partition supporting bridge type B and the mixed bridge type C can be respectively 0.207, 0.065 and 0.018, and the bottom of the groove of the motor can be greatly reduced, so that the power density of the motor is greatly improved.

As shown in fig. 5, 6 and 13, the outer arc surfaces of the full-bridge lamination and the half-bridge lamination both adopt five-segment spline structures to reduce torque fluctuation and improve motor vibration noise, and each rotor sector adopts the structure, namely, a central angle α of an arc segment main spline D concentric with the stator in the middle, two eccentric arc line splines E with central angles β 1 left and right adjacent to the arc segment main spline D and a straight-line segment spline F with central angles β 2 in the two edge segments should satisfy α +2 β 1+2 β 2 being 36 °.

By comparing and analyzing the rotor with the full-circle structure, the rotor with the traditional three-segment arc structure and the 5-segment spline rotor in the embodiment, the optimized no-load back electromotive force distortion rate is only 1.18%, and corresponding harmonic components are shown in fig. 14. In the embodiment, bulk molding compound is adopted to perform plastic coating and shaping on the rotor surface, and the maximum structural failure rotating speed of the motor is 19000rpm which is more than 6 times of the actual operating rotating speed of the motor, so that the rotor surface structural design of the embodiment can ensure the high sine property and the sufficient structural strength of the air gap magnetic field.

The preferred embodiments of the present invention have been described in detail with reference to the accompanying drawings, however, the present invention is not limited to the specific details of the above embodiments, and various simple modifications can be made to the technical solution of the present invention within the technical idea of the present invention, and these simple modifications are within the protective scope of the present invention.

It should be noted that the various technical features described in the above embodiments can be combined in any suitable manner without contradiction, and the invention is not described in any way for the possible combinations in order to avoid unnecessary repetition.

In addition, any combination of the various embodiments of the present invention is also possible, and the same should be considered as the disclosure of the present invention as long as it does not depart from the spirit of the present invention.

Claims

1. a permanent magnet motor, comprising a casing, a stator iron core and a rotor iron core; the rotor iron core is installed in the space enclosed by the stator iron core; it is characterized in that,

The rotor core includes at least two fully connected bridge lamination stacks and at least one semi-connected bridge lamination stack, wherein the laminations in the fully connected bridge lamination stack include a first central connection bridge and a second central connection bridge. A plurality of full-connection bridge punches that are connected by the central connecting bridges and distributed along the circumferential direction, the laminations in the semi-connecting bridge lamination group include a second central connecting bridge and at least one central connecting bridge disconnected from the second central connecting bridge And for the separated punching pieces distributed along the circumferential direction, the adjacent sectors of the rotor core are asymmetrical;

The stator iron core is formed by a plurality of T-shaped toothed yokes, the outer surface of each T-shaped toothed yoke is parallel to the bottom of the stator slot, and the teeth of the T-shaped toothed yoke are connected to the side of the yoke. The interface is vertical, and the number of the T-shaped toothed yokes is equal to the number of motor slots.

2 . The permanent magnet motor according to claim 1 , wherein the fully-connected bridge-type lamination group comprises a plurality of fully-connected bridge-type laminations, and the half-connected bridge-type lamination group comprises a plurality of semi-connected bridge laminations. 3 . Bridge laminations, the fully connected bridge lamination stack and the half-connected bridge lamination stack are axially stacked so that each of the half-connected bridge stacks is located at two of the fully connected bridge stacks. between the laminations.

3 . The permanent magnet motor according to claim 2 , wherein the fully-connected bridge laminations comprise a plurality of the fully-connected bridge punches, and there are support bridges between adjacent fully-connected bridge punches. 4 . .

4 . The permanent magnet motor according to claim 3 , wherein the fully connected bridge punching piece has a first narrow magnetic bridge, and the first narrow magnetic bridge extends radially outward to form a first sector; 4 . Permanent magnets are placed in the slots between the adjacent first sectors, and the first central connecting bridges protrude outward along the radial direction of the corresponding slots to form the support bridges, and the support bridges are connected to the permanent magnets. magnet contact.

5 . The permanent magnet motor of claim 3 , wherein the fully connected bridge punching piece has a first narrow magnetic bridge, and the width of the first narrow magnetic bridge is smaller than the width of the support bridge. 6 .

6 . The permanent magnet motor according to claim 2 , wherein the half-connected bridge laminations comprise a plurality of the half-connected bridge punching pieces and a plurality of the separated punching pieces, and two adjacent ones of the There is a separate punching piece between the half-connected bridge punching pieces, and the separating punching piece is not in contact with the half-connecting bridge punching piece; the adjacent half-connecting bridge punching piece and the separating punching piece With partition type support bridge.

7 . The permanent magnet motor of claim 6 , wherein the half-bridge punching piece has a second narrow magnetic bridge, and the second narrow magnetic bridge extends radially outward to form a second sector. 8 .

8 . The permanent magnet motor according to claim 7 , wherein permanent magnets are placed in the slots between the adjacent second sectors, and the second central connecting bridges extend along the radial direction of the corresponding slots. The partition-type support bridge is formed by extending outward; the partition-type support bridge is separated from the permanent magnet.

9 . The permanent magnet motor according to claim 8 , wherein the distance between the partitioned support bridge and the permanent magnet is smaller than the length of the magnetic bridge of the full-connected bridge punching piece. 10 .

10 . The permanent magnet motor according to claim 1 , wherein the outer arc surfaces of each of the half-connected bridge punching pieces and each of the separate punching pieces comprise multi-segment splines; 10 .

The spline at least includes a main spline of a circular arc segment and a straight segment spline separately arranged on both sides of the main spline of the circular arc segment.