Composite sub-magnetic pole, stepped composite magnetic pole, rotor and axial flux permanent magnet motor

Abstract

The invention relates to the technical field of axial flux permanent magnet motors, and provides a composite sub-magnetic pole, a stepped composite magnetic pole, a rotor and an axial flux permanent magnet motor. The composite sub-magnetic pole comprises a permanent magnet, a first pole shoe and a second pole shoe, and the permanent magnet is arranged in a cuboid shape; the first pole shoe is attached to the upper surface of the permanent magnet. The first pole shoe comprises a first shoe body and two first shoe shoulders arranged on the left side and the right side of the first shoe body respectively. In the front-back direction of the first pole shoe, the first pole shoe is formed by laminating a plurality of silicon steel sheets with the same size; the second pole shoe is attached to the lower surface of the permanent magnet. The second pole shoe comprises a second shoe body and two second shoe shoulders arranged on the left side and the right side of the second shoe body respectively. And along the front-back direction of the second pole shoe, the second pole shoe is formed by laminating a plurality of silicon steel sheets with the same size. The first pole shoe and the second pole shoe are formed by laminating the silicon steel sheets with the same specification and size, the permanent magnet is a cuboid, a boss does not need to be machined and installed, and the pole shoes and the permanent magnet are easy to produce and manufacture and low in manufacturing cost.

Description

Technical Field

[0001] The invention relates to the technical field of axial flux permanent magnet motors, and in particular to a composite sub-pole, a stepped composite pole, a rotor and an axial flux permanent magnet motor. Background Art

[0002] Axial flux motors have the characteristics of short axial dimensions and high power density, and are suitable for use in places such as elevators, automobiles, and warships where strict axial dimension requirements are required. However, most dual-stator single-rotor axial flux permanent magnet motors use a surface-mounted rotor structure, and the armature magnetic field harmonics will generate eddy current losses in the rotor permanent magnets. At present, the surface-mounted rotor permanent magnets of axial flux permanent magnet motors are divided into multiple pieces to reduce eddy current losses. In addition, in order to fix the surface-mounted permanent magnets to the rotor disk, it is necessary to machine bosses around the permanent magnets. The structure of the conventional boss permanent magnets in the prior art is as follows: Fig.10 As shown, this permanent magnet structure greatly increases the permanent magnet processing cost.

[0003] In order to solve the eddy current loss of the rotor permanent magnet and reduce the processing cost of the permanent magnet, patents CN 211655867U and CN115360842 A proposed a sandwich structure magnetic pole, which installs soft magnetic pole shoes on the surface of the permanent magnet, effectively reducing the eddy current loss in the permanent magnet, reducing the processing technology of the rotor disk assembly, and improving the demagnetization resistance and weak magnetic speed regulation ability of the permanent magnet. Fig.11 and Fig.12 However, the magnetic poles in the above patents are fan-shaped or trapezoidal, which requires that the pole shoes and permanent magnets are fan-shaped or trapezoidal in shape. The fan-shaped or trapezoidal soft magnetic pole shoes are formed by laminating silicon steel sheets, which is complex in process, time-consuming and economically expensive. At the same time, the processing cost of fan-shaped or trapezoidal permanent magnets is also higher than that of rectangular permanent magnets.

[0004] Therefore, how to use effective means to reduce the rotor eddy current loss and manufacturing cost of the axial flux permanent magnet motor is one of the key technical problems that high-speed, high-power axial flux permanent magnet motors need to solve. Summary of the invention

[0005] The object of the present invention is to provide a composite sub-pole, a stepped composite magnetic pole, a rotor and an axial flux permanent magnet motor to solve the problem of high manufacturing cost of magnetic poles in the prior art.

[0006] In order to achieve the above-mentioned purpose, according to a first aspect of the present invention, there is provided a composite sub-pole, comprising: a permanent magnet, which is arranged in a rectangular parallelepiped; a first pole shoe, which is attached to the upper surface of the permanent magnet, and the first pole shoe comprises a first shoe body and two first shoe shoulders respectively arranged on the left and right sides of the first shoe body, and the heights of the two first shoe shoulders are both lower than the height of the first shoe body; along the front-to-back direction of the first pole shoe, the first pole shoe is formed by stacking a plurality of silicon steel sheets of the same size; a second pole shoe, which is attached to the lower surface of the permanent magnet, and the second pole shoe comprises a second shoe body and two second shoe shoulders respectively arranged on the left and right sides of the second shoe body, and the heights of the two second shoe shoulders are both lower than the height of the second shoe body; along the front-to-back direction of the second pole shoe, the second pole shoe is formed by stacking a plurality of silicon steel sheets of the same size.

[0007] Furthermore, the permanent magnet is an integrally formed permanent magnet, or the permanent magnet is formed by splicing multiple sub-permanent magnets, and two adjacent sub-permanent magnets are bonded by insulating glue; the first pole shoe and the permanent magnet are bonded by insulating glue; and the second pole shoe and the permanent magnet are bonded by insulating glue.

[0008] According to a second aspect of the present invention, a stepped composite magnetic pole is provided, comprising a plurality of composite sub-magnetic poles spliced ​​together, the composite sub-magnetic poles being the composite sub-magnetic poles mentioned above; along the direction from front to back, the width of two adjacent composite sub-magnetic poles in the left and right directions gradually increases to form a stepped composite magnetic pole.

[0009] Furthermore, in the height direction, the thickness of each composite sub-poles is equal; in the front-back direction, the length of each composite sub-poles is equal; the number of composite sub-poles is 3 or 4; and two adjacent composite sub-poles are bonded by insulating glue.

[0010] According to a third aspect of the present invention, a rotor is provided, comprising: a plurality of stepped composite magnetic poles, the stepped composite magnetic poles being the above-mentioned stepped composite magnetic poles; a rotor support, the rotor support having a plurality of magnetic pole mounting slots arranged at intervals along its circumference, the plurality of stepped composite magnetic poles being mounted in the plurality of magnetic pole mounting slots in a one-to-one correspondence; a supporting rib is formed between each two adjacent magnetic pole mounting slots, the supporting rib is provided with at least one first locking hole; a plurality of pressure strips, each pressure strip is provided with a second locking hole matched with the first locking hole, the plurality of pressure strips are mounted in a one-to-one correspondence on the plurality of supporting ribs; a plurality of fixing members, each fixing member passes through a corresponding second locking hole and a first locking hole in turn, the plurality of pressure strips are fixedly connected to the rotor support, and the plurality of stepped composite magnetic poles are respectively confined in the plurality of magnetic pole mounting slots.

[0011] Furthermore, along the radial direction of the rotor support, each pole mounting slot includes a plurality of interconnected sub-slot segments, and the sizes of the plurality of sub-slot segments correspond one by one to the sizes of the plurality of composite sub-poles of the stepped composite magnetic pole; along the axial direction of the rotor support, each sub-slot segment includes a first slot segment and a second slot segment that are interconnected; the width of the first slot segment is greater than the width of the second slot segment, so as to form two slot shoulders on both sides of each sub-slot segment that respectively stop and cooperate with the two second pole shoes of the composite sub-pole; each supporting rib is arranged in a serrated shape; each pressure strip is arranged in a serrated shape; along the circumferential direction of the rotor support, the width of the pressure strip is greater than the width of the supporting rib, so as to form two stop segments on both sides of the pressure strip that respectively stop and cooperate with the two first pole shoes of the composite sub-pole.

[0012] Furthermore, along the radial direction of the rotor bracket, each supporting rib is provided with a plurality of first locking holes at intervals; each pressure strip is a flat structure, and each pressure strip is provided with a plurality of second locking holes at intervals, and the plurality of second locking holes correspond one by one to the plurality of first locking holes, and each pressure strip is installed on the rotor bracket through a plurality of fixing parts; the pressure strip is made of non-magnetic material; and the rotor bracket is made of non-magnetic high-strength material.

[0013] Furthermore, the permanent magnets in the multiple composite sub-poles in each stepped composite magnetic pole have the same magnetic properties; along the circumferential direction of the rotor support, the permanent magnets in two adjacent stepped composite magnetic poles have opposite magnetic properties.

[0014] Furthermore, the number of magnetic poles is an even number and can be divided by 4; the permanent magnets in the multiple composite sub-poles in each stepped composite magnetic pole have the same magnetic properties; two adjacent stepped composite magnetic poles with the same magnetic properties form a group of magnetic poles, constituting an N pole or an S pole; along the circumference of the rotor bracket, multiple groups of magnetic poles are arranged on the rotor bracket, the magnetic properties of two adjacent groups of magnetic poles are opposite, and the N poles and the S poles are arranged alternately.

[0015] According to a fourth aspect of the present invention, an axial flux permanent magnet motor is provided, which comprises a rotor, a stator, a rotating shaft, a bearing and a base, wherein the stator comprises a first stator and a second stator, the rotor is fixedly connected to the rotating shaft, two bearings are respectively sleeved at both ends of the rotating shaft, and the rotating shaft is rotatably mounted on the base through the two bearings; along the axial direction of the rotating shaft, the first stator and the second stator are mirror-imaged on both sides of the rotor and are respectively fixed on the base, an axial gap exists between the rotor and the first stator and the second stator, and the rotor and the stator can rotate relative to each other; the first stator and the second stator both comprise a stator core and a multi-phase AC winding, the stator core comprises stator teeth and stator slots, and the multi-phase AC winding is embedded in the stator slots; wherein the rotor is the above-mentioned rotor.

[0016] By applying the technical solution of the present invention, the first pole shoe and the second pole shoe can be laminated with silicon steel sheets of the same specifications and sizes, and the production process of the pole shoe is simple and the manufacturing cost is low; the permanent magnet is a rectangular parallelepiped, and no processing and mounting boss is required, and the production and manufacturing of the permanent magnet is simple and the manufacturing cost is low. Therefore, the composite sub-pole provided by the present invention solves the technical problem of high manufacturing cost of the magnetic pole in the prior art, and has the beneficial technical effect of low manufacturing cost.

[0017] Based on the implementations provided in the above aspects, this application can also be further combined to provide more implementations. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0019] Figure 1 A schematic cross-sectional view of an axial flux permanent magnet motor provided by an optional embodiment of the present invention;

[0020] Figure 2 A schematic diagram of the assembly structure of a rotor provided in Example 1 of the present invention;

[0021] Figure 3 An exploded view of a rotor provided in Example 1 of the present invention;

[0022] Figure 4 A schematic diagram of the structure of a stepped composite magnetic pole provided in an optional embodiment of the present invention;

[0023] Figure 5 A schematic structural diagram of a rotor support in a rotor provided in an optional embodiment of the present invention;

[0024] Figure 6 A schematic diagram of the disassembled structure of a composite sub-pole provided in an optional embodiment of the present invention;

[0025] Figure 7 A schematic structural diagram of a stator of an axial flux permanent magnet motor provided in an optional embodiment of the present invention;

[0026] Figure 8 A schematic diagram of the structure of a partially disassembled rotor provided in Example 2 of the present invention;

[0027] Fig. 9 An exploded view of a rotor provided in Example 2 of the present invention;

[0028] Fig.10 It is a schematic diagram of the structure of a conventional boss permanent magnet in the prior art;

[0029] Fig.11 It is a schematic structural diagram of a conventional magnetic pole with pole shoes arranged in a trapezoidal shape in the prior art;

[0030] Fig.12 It is a schematic diagram of the structure of a conventional magnetic pole with pole shoes arranged in a fan shape in the prior art;

[0031] Fig.13 A comparison diagram of the loss of a stepped composite magnetic pole provided in an optional embodiment of the present invention and the loss of a conventional poleless shoe permanent magnet;

[0032] Description of Figure Numbers:

[0033] 1. rotor; 100. stepped composite magnetic pole; 1001. composite sub-magnetic pole; 1002. permanent magnet; 1003. pole shoe; 10031. first pole shoe; 100311. first shoe body; 100312. first shoe shoulder; 10032. second pole shoe; 100321. second shoe body; 100322. second shoe shoulder; 101. rotor bracket; 1011. bracket; 1012. magnetic pole mounting slot; 1013. slot Shoulder; 11. sub-slot section; 12. first slot section; 13. second slot section; 1014. supporting rib; 1015. first locking hole; 102. pressure strip; 1021. second locking hole; 103. fixing piece; 2. stator; 21. first stator; 22. second stator; 201. stator core; 2011. stator teeth; 2012. stator slot; 202. multi-phase AC winding; 3. rotating shaft; 4. bearing; 5. gap; 6. base. DETAILED DESCRIPTION

[0034] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only embodiments of a part of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention. Unless otherwise specified, the technical means used in the embodiments are conventional means well known to those skilled in the art.

[0035] like Figure 4 and Figure 6As shown, the present invention provides a composite sub-pole 1001, the composite sub-pole 1001 includes a permanent magnet 1002, a first pole shoe 10031 and a second pole shoe 10032, the permanent magnet 1002 is arranged in a rectangular parallelepiped; the first pole shoe 10031 is attached to the upper surface of the permanent magnet 1002, the first pole shoe 10031 includes a first shoe body 100311 and two first shoe shoulders 100312 respectively arranged on the left and right sides of the first shoe body 100311, the heights of the two first shoe shoulders 100312 are lower than the height of the first shoe body 100311; along the first pole In the front-to-back direction of the shoe 10031, the first pole shoe 10031 is formed by laminating a plurality of silicon steel sheets of the same size; the second pole shoe 10032 is attached to the lower surface of the permanent magnet 1002, and the second pole shoe 10032 includes a second shoe body 100321 and two second shoe shoulders 100322 respectively arranged on the left and right sides of the second shoe body 100321, and the heights of the two second shoe shoulders 100322 are both lower than the height of the second shoe body 100321; along the front-to-back direction of the second pole shoe 10032, the second pole shoe 10032 is formed by laminating a plurality of silicon steel sheets of the same size. The first pole shoe 10031 and the second pole shoe 10032 are arranged symmetrically on the upper and lower sides of the permanent magnet 1002. In this way, the first pole shoe 10031 and the second pole shoe 10032 can be laminated with silicon steel sheets of the same specification and size, so that the production and manufacturing process of the pole shoe 1003 is simple and the manufacturing cost is low; the permanent magnet 1002 is a rectangular parallelepiped, and does not need to be processed and installed with a boss, so the production and manufacturing of the permanent magnet 1002 is simple and the manufacturing cost is low. Therefore, the composite sub-pole 1001 provided by the present invention solves the technical problem of high manufacturing cost of the magnetic pole in the prior art, and has a beneficial technical effect of low manufacturing cost. At the same time, the first pole shoe 10031 and the second pole shoe 10032 attached to the upper and lower sides of the permanent magnet 1002 can short-circuit most of the harmonic magnetic fields generated by the armature winding, reduce the harmonic magnetic field passing through the permanent magnet, and thus reduce the eddy current loss of the permanent magnet.

[0036] Alternatively, if Figure 4 and Figure 6 As shown, the permanent magnet 1002 is an integrally formed permanent magnet 1002. This is beneficial to improving assembly efficiency.

[0037] In an optional embodiment not shown in the figure of the present application, the permanent magnet 1002 is formed by splicing multiple sub-permanent magnets, and two adjacent sub-permanent magnets are bonded by insulating glue. Dividing the permanent magnet into blocks is conducive to reducing the eddy current loss of the permanent magnet.

[0038] Optionally, the permanent magnet can be divided into multiple pieces of sub-permanent magnets along the axial direction Z, the circumferential direction C or the radial direction R. The permanent magnets of the rotor of the conventional dual-stator axial flux permanent magnet motor can only be divided along the circumferential direction C, such as Figure 8As shown, or divided along the radial direction R, otherwise the rotor permanent magnet cannot be installed and fixed. However, the present application can also divide the permanent magnet along the axial direction Z. It can be seen that the technical solution provided by the present application can divide the permanent magnet more flexibly.

[0039] Optionally, the first pole shoe 10031 and the permanent magnet 1002 are bonded together by insulating glue; the second pole shoe 10032 and the permanent magnet 1002 are bonded together by insulating glue. In this way, the assembly is simple and reliable.

[0040] like Figure 4 As shown, the present invention also provides a stepped composite magnetic pole 100, which includes a plurality of composite sub-poles 1001 spliced ​​together, and the composite sub-poles 1001 are the composite sub-poles mentioned above; along the direction from front to back, the widths of two adjacent composite sub-poles 1001 in the left and right directions gradually increase to form a stepped composite magnetic pole.

[0041] Alternatively, if Figure 4 As shown, in the height direction, the thickness of each composite sub-pole 1001 is equal, so as to facilitate processing and manufacturing and further reduce costs.

[0042] Alternatively, if Figure 4 As shown, in the front-to-back direction, the lengths of the composite sub-poles 1001 are all equal, which facilitates processing and manufacturing and further reduces costs.

[0043] In an optional embodiment not shown in the figure of the present application, the lengths of the composite sub-poles 1001 in the front-to-back direction may also be unequal, and the lengths are designed according to actual needs.

[0044] Optionally, the number of composite sub-poles 1001 is 3 or 4.

[0045] Optionally, two adjacent composite sub-poles 1001 are bonded together by insulating glue. In this way, the assembly is simple and reliable, and the stepped composite magnetic pole 100 can be magnetized as a whole after the assembly is completed.

[0046] like Figure 2 , Figure 3 , Figure 8 and Fig. 9As shown, the present invention also provides a rotor, the rotor comprising: a plurality of stepped composite magnetic poles 100, the stepped composite magnetic poles 100 being the aforementioned stepped composite magnetic poles; a rotor bracket 101, the rotor bracket 101 having a plurality of magnetic pole mounting grooves 1012 arranged at intervals along its circumference, the plurality of stepped composite magnetic poles 100 being mounted in the plurality of magnetic pole mounting grooves 1012 in a one-to-one correspondence; a support rib 1014 being formed between each two adjacent magnetic pole mounting grooves 1012, the support rib 1014 being provided with at least one first locking hole 1 015; multiple beadings 102, each beading 102 is provided with a second locking hole 1021 adapted to the first locking hole 1015, and multiple beadings 102 are installed on multiple supporting ribs 1014 in a one-to-one correspondence; multiple fixings 103, each fixing 103 sequentially passes through a corresponding second locking hole 1021 and a first locking hole 1015, and multiple beadings 102 are fixedly connected with the rotor bracket 101, and multiple stepped composite magnetic poles 100 are respectively restricted in multiple magnetic pole mounting grooves 1012. In this way, the stepped composite magnetic poles 100 are installed on the rotor bracket 101 by using the beading 102. The rotor provided by the present invention has the advantages of easy processing and manufacturing and low cost.

[0047] Alternatively, if Figure 5 As shown, along the radial direction of the rotor bracket 101, each magnetic pole mounting slot 1012 includes a plurality of interconnected sub-slot segments 11, and the sizes of the plurality of sub-slot segments 11 correspond one by one to the sizes of the plurality of composite sub-poles 1001 of the stepped composite magnetic pole 100; along the axial direction of the rotor bracket 101, each sub-slot segment 11 includes a first slot segment 12 and a second slot segment 13 that are interconnected; the width of the first slot segment 12 is greater than the width of the second slot segment 13, so as to form two slot shoulders 1013 on both sides of each sub-slot segment 11 that respectively stop and cooperate with the two second pole shoes 10032 of the composite sub-pole 1001; each supporting rib 1014 is serrated; each pressure strip 102 is serrated; along the circumferential direction of the rotor bracket 101, the width of the pressure strip 102 is greater than the width of the supporting rib 1014, so as to form two stop segments on both sides of the pressure strip 102 that respectively stop and cooperate with the two first pole shoes 10031 of the composite sub-pole 1001. In this way, the stepped composite magnetic pole 100 is installed in the magnetic pole mounting groove 1012 by using the stop sections formed by the two groove shoulders 1013 and the two side edges of the pressure strip 102 to cooperate with the two second shoe shoulders 100322 of the second pole shoe 10032 and the two first shoe shoulders 100312 of the first pole shoe 10031 respectively.

[0048] Optionally, along the radial direction of the rotor support 101, each support rib 1014 is provided with a plurality of first locking holes 1015 at intervals; each bead 102 is a flat structure, each bead 102 is provided with a plurality of second locking holes 1021 at intervals, the plurality of second locking holes 1021 correspond to the plurality of first locking holes 1015 one by one, and each bead 102 is installed on the rotor support 101 through a plurality of fixing members 103. In this way, by increasing the number of fixing members 103, the connection stability between the bead 102 and the rotor support 101 is improved.

[0049] Optionally, the pressure strip 102 is made of non-magnetic material.

[0050] Optionally, the rotor support 101 is made of a non-magnetic high-strength material.

[0051] like Figure 3 As shown, in the illustrated embodiment 1 of the present application, the permanent magnets 1002 in the multiple composite sub-poles 1001 in each stepped composite magnetic pole 100 have the same magnetic properties; along the circumferential direction of the rotor support 101, the permanent magnets 1002 in two adjacent stepped composite magnetic poles 100 have opposite magnetic properties.

[0052] like Figure 8 and Fig. 9 As shown, in the illustrated embodiment 2 of the present application, the number of magnetic poles is an even number and can be divided by 4; the permanent magnets 1002 in the multiple composite sub-poles 1001 in each stepped composite magnetic pole 100 have the same magnetic properties; two adjacent stepped composite magnetic poles 100 with the same magnetic properties form a group of magnetic poles, constituting an N pole or an S pole; along the circumference of the rotor bracket 101, multiple groups of magnetic poles are arranged on the rotor bracket 101, and the magnetic properties of two adjacent groups of magnetic poles are opposite, and the N poles and the S poles are arranged alternately. In this way, the two stepped composite magnetic poles 100 in embodiment 2 play the same role as one stepped composite magnetic pole 100 in embodiment 1. In this way, one N pole or S pole is composed of two stepped composite magnetic poles 100, which reduces the cross-sectional area of ​​a whole N pole or S pole and improves the strength of a single stepped composite magnetic pole 100.

[0053] According to a fourth aspect of the present invention, Figure 1 As shown, an axial flux permanent magnet motor is provided, which includes a rotor 1, a stator 2, a rotating shaft 3, a bearing 4 and a base 6. The stator 2 includes a first stator 21 and a second stator 22. The rotor 1 is fixedly connected to the rotating shaft 3. The two bearings 4 are respectively sleeved at both ends of the rotating shaft 3. The rotating shaft 3 is rotatably mounted on the base 6 through the two bearings 4. Along the axial direction of the rotating shaft 3, the first stator 21 and the second stator 22 are mirror-imaged on both sides of the rotor 1 and are respectively fixed on the base 6. There is an axial gap 5 between the rotor 1 and the first stator 21 and the second stator 22, and the rotor 1 and the stator 2 can rotate relative to each other. Figure 7As shown, the first stator 21 and the second stator 22 both include a stator core 201 and a multi-phase AC winding 202, the stator core 201 includes stator teeth 2011 and stator slots 2012, and the multi-phase AC winding 202 is embedded in the stator slots 2012; wherein the rotor 1 is the above-mentioned rotor. Thus, the axial flux permanent magnet motor provided by the present invention uses the stepped composite magnetic pole 100 provided by the present invention, and has the advantage of low cost.

[0054] The following is a further detailed description of the illustrated embodiment 1 of the present invention:

[0055] Embodiment 1 relates to the technical field of axial flux permanent magnet motors, and in particular to the rotor of a dual-stator single-rotor axial flux permanent magnet motor.

[0056] Embodiment 1 provides a stepped composite magnetic pole axial flux permanent magnet motor, such as Figure 1 As shown, it includes a rotor 1, a stator 2, a rotating shaft 3, and a bearing 4. The stator 2 includes a first stator 21 and a second stator 22. The rotor 1 is fixed to the rotating shaft 3. The bearings 4 are sleeved at both ends of the rotating shaft 3. The first stator 21 and the second stator 22 are mirror-imaged on both sides of the rotor 1. There is an axial gap 5 between the rotor 1 and the stator 2, and the rotor 1 and the stator 2 can rotate relative to each other.

[0057] like Figure 2 , Figure 3 As shown, the rotor 1 includes a stepped composite magnetic pole 100, a rotor bracket 101, a serrated bead 102, and a fixing member 103. A magnetic pole mounting groove 1012 is provided on the rotor bracket 101, and the stepped composite magnetic pole 100 is built into the magnetic pole mounting groove 1012. The size of the magnetic pole mounting groove 1012 matches the size of the stepped composite magnetic pole 100. A plurality of serrated bead 102 are radially pressed on the stepped composite magnetic pole 100 along the circumference to prevent the stepped composite magnetic pole 100 from axial movement. The fixing member 103 fixes the serrated bead 102 to the rotor bracket 101.

[0058] like Figure 2 , Figure 3 , Figure 4As shown, each stepped composite magnetic pole 100 is composed of N composite sub-poles 1001 of different sizes; N is 3 or 4; the N composite sub-poles 1001 in the same stepped composite magnetic pole 100 have different widths along the circumferential direction C, the same thickness along the axial direction Z, and the length along the radial direction R is designed according to needs, and the torque fluctuation of the motor can be improved by adjusting the width of the composite sub-poles 1001 along the circumferential direction C; the composite sub-poles 1001 include permanent magnets 1002 and pole shoes 1003, the pole shoes 1003 are attached to both sides of the permanent magnets 1002, and insulating glue is applied between the permanent magnets 1002 and the pole shoes 1003 to bond the two together, and the pole shoes 1003 attached to both sides of the permanent magnets 1002 can short-circuit most of the harmonic magnetic fields generated by the armature windings, reducing the harmonic magnetic fields passing through the permanent magnets 1002, thereby reducing the eddy current losses of the permanent magnets 1002.

[0059] like Figure 5 As shown, the rotor bracket 101 also includes a frame body 1011, a slot shoulder 1013, a support rib 1014, and a first locking hole 1015. The support rib 1014 is serrated. The slot shoulder 1013 and the serrated pressure strip 102 together restrict the stepped composite magnetic pole 100 in the pole mounting slot 1012 to prevent the stepped composite magnetic pole 100 from moving in the axial Z direction. The support rib 1014 is arranged in a circumferential array along the frame body 1011. The first locking hole 1015 is opened on the support rib 1014. The rotor bracket 101 is made of a high-strength material that is not magnetically conductive.

[0060] like Figure 2 , Figure 3 As shown, the sawtooth-shaped pressure strip 102 is a flat structure with second locking holes 1021 formed thereon. The number of the second locking holes 1021 is the same as the number of the first locking holes 1015 formed on the supporting rib 1014. The sawtooth-shaped pressure strip 102 is made of non-magnetic material.

[0061] like Figure 6 As shown, the pole shoe 1003 includes a first pole shoe 10031 and a second pole shoe 10032. The first pole shoe 10031 includes a first shoe body 100311 and a first shoe shoulder 100312. The first shoe body 100311 is provided with first shoe shoulders 100312 on both sides. The second pole shoe 10032 includes a second shoe body 100321 and a second shoe shoulder 100322. The first pole shoe 10031 and the second pole shoe 10032 are both formed by stacking silicon steel sheets along the radial direction R. The silicon steel sheets constituting the first pole shoe 10031 and the second pole shoe 10032 are of the same size. One side of the second shoe shoulder 100322 is engaged with the slot shoulder 1013, and the other side of the first shoe shoulder 100312 is engaged with the sawtooth-shaped pressure strip 102. For the trapezoidal or fan-shaped pole shoes of the traditional axial flux motor, as shown in FIG. Fig.11 and Fig.12As shown, each silicon steel sheet constituting the pole shoe has a different size, which makes manufacturing difficult and costly. The silicon steel sheets of the pole shoe of the present invention have consistent sizes, which reduces the difficulty and cost of manufacturing.

[0062] like Figure 6 As shown, the permanent magnet 1002 is rectangular and can be a whole piece or can be divided into multiple pieces and spliced ​​along the axial direction Z, circumferential direction C and radial direction R. The rotor permanent magnet of the present invention does not need to be processed as shown in FIG. Fig.10 The present invention reduces the processing cost by using the mounting boss shown in the figure. In addition, the permanent magnet of the present invention can be divided into multiple pieces, which is beneficial to reduce the eddy current loss of the permanent magnet. The rotor permanent magnet of the traditional double-stator axial flux permanent magnet motor can only be divided into pieces along the circumferential direction C. Fig.10 As shown, or radial R segmentation, otherwise the rotor permanent magnets cannot be installed and fixed.

[0063] like Figure 3 and Figure 4 As shown, N composite sub-poles 1001 are bonded together by insulating glue, and then the stepped composite magnetic pole 100 is magnetized as a whole.

[0064] like Figure 7 As shown, the stator 2 is fixed on the base 6 , and the stator 2 includes a stator core 201 and a multi-phase AC winding 202 . The stator core 201 includes stator teeth 2011 and stator slots 2012 , and the multi-phase AC winding 202 is embedded in the stator slots 2012 .

[0065] Fig.13 The loss of the rotor magnetic pole of a motor after adopting the technology of the present invention includes the pole shoe finite element simulation result of 50.75W, while the pole loss of the traditional pole shoeless magnetic pole axial flux permanent magnet motor is 231.28W. It can be seen that after adopting the technology of the present invention, the rotor magnetic pole loss is greatly reduced.

[0066] The stepped composite magnetic pole axial flux permanent magnet motor of the present invention not only reduces the manufacturing cost of the double-stator axial flux permanent magnet motor, but also reduces the loss of the motor rotor and enhances the operating reliability of the motor.

[0067] The specific advantages of the present invention are as follows:

[0068] 1) In the stepped composite magnetic pole axial flux permanent magnet motor of the present invention, the soft magnetic pole shoe is a rectangular parallelepiped, and each sub-pole shoe is formed by stacking silicon steel sheets of the same specification and size. The pole shoe production process is simple and the manufacturing cost is low.

[0069] 2) The step-type composite magnetic pole axial flux permanent magnet motor of the present invention has a rectangular permanent magnet, which does not need to be divided into blocks or processed with mounting bosses. The permanent magnet is easy to manufacture and has a low manufacturing cost.

[0070] 3) In the stepped composite magnetic pole axial flux permanent magnet motor of the present invention, the soft magnetic pole shoes short-circuit most of the armature magnetic field harmonics, reducing the harmonics penetrating into the rotor permanent magnets, thereby reducing the eddy current loss of the permanent magnets and improving the reliability of the operation of the high-speed, high-power axial flux permanent magnet motor.

[0071] The following is a further detailed description of the embodiment 2 of the present invention:

[0072] The difference between Example 2 and Example 1 is that the polarities of two adjacent stepped composite magnetic poles 100 are the same.

[0073] Surface-mounted axial flux permanent magnet motors have the characteristics of high torque density, short axial size, and compact structure. However, high-power and large-diameter motors have the following problems: 1. If a large number of poles is selected, a large amount of eddy current losses will be generated in the pole holder and the rotor permanent magnets; 2. If a small number of poles is selected, the cross-sectional area of ​​an N pole or S pole will be large, which will be easily broken under the action of electromagnetic force and centrifugal force.

[0074] In order to reduce the rotor eddy current loss, the related technologies CN201911286316.0 and CN111010008A proposed a pole shoe composite pole structure to reduce the eddy current loss of the rotor permanent magnet, but this structure is suitable for motors with a large number of poles or a small diameter, and cannot reduce the eddy current loss of the pole holder. For high-power, large-diameter axial flux permanent magnet motors, a small number of poles is the most effective measure to reduce rotor eddy current loss, which puts higher requirements on the rotor pole strength. Therefore, reducing the rotor eddy current loss of axial flux permanent magnet motors and improving the rotor structural strength is one of the key technical problems that need to be solved urgently for high-power, large-diameter axial flux permanent magnet motors.

[0075] Embodiment 2 of the present invention relates to the technical field of axial flux permanent magnet motors, in particular to medium-low speed, high-power dual-stator single-rotor axial flux permanent magnet motor rotors.

[0076] Embodiment 2 discloses a split-pole axial flux permanent magnet motor, comprising a rotor 1, a stator 2, a rotating shaft 3, a bearing 4, a gap 5, and a base 6. The stator 2 comprises a first stator 21 and a second stator 22. The rotor 1 is arranged on the rotating shaft 3. Bearings 4 are sleeved at both ends of the rotating shaft 3. The bearings 4 are fixed on the base 6. The rotor 1 is clamped in the stator 2. There is a gap 5 between the rotor 1 and the stator 2, and the rotor 1 and the stator 2 can rotate relative to each other.

[0077] like Figure 8 and Fig. 9 As shown, the rotor 1 includes a stepped composite magnetic pole 100, a rotor bracket 101, a sawtooth-shaped pressure strip 102, and a fixing member 103. The conventional composite magnetic pole is as shown in FIG. Fig.12As shown, the circumferential span of the permanent magnet of this structure is large, which can easily cause the permanent magnet to break. In addition, the permanent magnet of this structure is mostly fan-shaped or trapezoidal, which has high processing cost and causes waste of permanent magnets. Therefore, the present invention divides a single permanent magnet of a traditional composite magnetic pole into two pieces, and the two adjacent stepped composite magnetic poles 100 have the same polarity, forming the N pole or S pole of the motor, and the two adjacent stepped composite magnetic poles 100 in the clockwise or counterclockwise direction have the same polarity, forming the S pole or N pole of the motor. A magnetic pole mounting groove 1012 is provided on the rotor bracket 101, and the stepped composite magnetic pole 100 is built into the magnetic pole mounting groove 1012 of the rotor bracket 101. A plurality of serrated beading strips 102 are radially pressed on the stepped composite magnetic pole 100 along the circumference, and the fixing member 103 fixes the serrated beading strip 102 on the rotor bracket 101.

[0078] The number of the stepped composite magnetic poles 100 in the motor of the present invention is an even number and can be divided by 4, while the number of magnetic poles in the conventional motor is an even number and can be divided by 2, that is, the two stepped composite magnetic poles 100 in the motor of the present invention play the same role as one magnetic pole in the conventional motor. In this way, one N pole or S pole is composed of two stepped composite magnetic poles 100, which reduces the cross-sectional area of ​​a whole N pole or S pole and improves the strength of a single stepped composite magnetic pole 100.

[0079] The invention solves the problems of insufficient rotor strength and large rotor eddy current loss in the existing high-power, large-diameter double-stator single-rotor axial flux permanent magnet motor.

[0080] The specific advantages of the present invention are as follows:

[0081] 1) The split-pole axial flux permanent magnet motor of the present invention divides the conventional magnetic pole into two parts along the circumferential direction C. The magnetizing directions of the two magnetic poles are consistent, which transforms a motor with a small number of poles into a motor with a large number of magnetic poles, reduces the cross-sectional area of ​​a single magnetic pole, increases the rotor strength, and further improves the reliability of the motor operation.

[0082] 2) The split-pole axial flux permanent magnet motor of the present invention reduces the difficulty of manufacturing large permanent magnets and can effectively reduce the manufacturing cost.

[0083] 3) The split-pole axial flux permanent magnet motor of the present invention reduces the motor operating frequency and the eddy current loss of the motor rotor by splitting one pole of the motor rotor into two poles of the same name and using a scheme with more poles and fewer poles.

[0084] The invention solves the problems of rotor strength, high permanent magnet manufacturing cost, large eddy current loss and small motor weak magnetic speed regulation range in the existing high-speed small-pole double-stator single-rotor axial flux permanent magnet motor.

[0085] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art who is familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

[0086] Unless otherwise defined, the technical terms or scientific terms used in the present disclosure should be understood by people with ordinary skills in the field to which the present disclosure belongs. The "first", "second" and similar words used in the present disclosure do not indicate any order, quantity or importance, but are only used to distinguish different components. Similarly, similar words such as "one", "one" or "the" do not indicate quantity restrictions, but indicate that there is at least one. Similar words such as "include" or "comprise" mean that the elements or objects appearing before the word cover the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Similar words such as "connect" or "connected" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

Claims

1. A composite sub-pole, characterized in that: include: A permanent magnet (1002), wherein the permanent magnet (1002) is arranged in a rectangular parallelepiped; A first pole shoe (10031), the first pole shoe (10031) being attached to the upper surface of the permanent magnet (1002), the first pole shoe (10031) comprising a first shoe body (100311) and two first shoe shoulders (100312) respectively arranged on the left and right sides of the first shoe body (100311), the heights of the two first shoe shoulders (100312) being lower than the height of the first shoe body (100311); along the front-to-back direction of the first pole shoe (10031), the first pole shoe (10031) is formed by stacking a plurality of silicon steel sheets of the same size; A second pole shoe (10032), wherein the second pole shoe (10032) is attached to the lower surface of the permanent magnet (1002), and the second pole shoe (10032) comprises a second shoe body (100321) and two second shoe shoulders (100322) respectively arranged on the left and right sides of the second shoe body (100321), and the heights of the two second shoe shoulders (100322) are both lower than the height of the second shoe body (100321); along the front-to-back direction of the second pole shoe (10032), the second pole shoe (10032) is formed by stacking a plurality of silicon steel sheets of the same size.

2. The composite sub-pole according to claim 1, characterized in that: The permanent magnet (1002) is an integrally formed permanent magnet (1002), or The permanent magnet (1002) is formed by splicing a plurality of sub-permanent magnets, and two adjacent sub-permanent magnets are bonded together by insulating glue; The first pole shoe (10031) and the permanent magnet (1002) are bonded together by insulating glue; The second pole shoe (10032) and the permanent magnet (1002) are bonded together by insulating glue.

3. A stepped composite magnetic pole, characterized in that: The stepped composite magnetic pole comprises a plurality of composite sub-magnetic poles (1001) spliced ​​together, and the composite sub-magnetic pole (1001) is the composite sub-magnetic pole described in claim 1 or 2; along the direction from front to back, the width of two adjacent composite sub-magnetic poles (1001) in the left-right direction gradually increases, forming a stepped composite magnetic pole.

4. The stepped composite magnetic pole according to claim 3, characterized in that: In the height direction, the thickness of each composite sub-pole (1001) is equal; In the front-to-back direction, the lengths of the composite sub-poles (1001) are all equal; The number of the composite sub-poles (1001) is 3 or 4; Two adjacent composite sub-poles (1001) are bonded together by insulating glue.

5. A rotor, characterized in that: The rotor comprises: A plurality of stepped composite magnetic poles (100), wherein the stepped composite magnetic poles (100) are the stepped composite magnetic poles as claimed in claim 3 or 4; A rotor support (101), the rotor support (101) having a plurality of magnetic pole mounting grooves (1012) arranged at intervals along its circumference, a plurality of the stepped composite magnetic poles (100) being mounted in the plurality of magnetic pole mounting grooves (1012) in a one-to-one correspondence; a support rib (1014) is formed between each two adjacent magnetic pole mounting grooves (1012), and at least one first locking hole (1015) is provided on the support rib (1014); A plurality of pressure strips (102), each of the pressure strips (102) being provided with a second locking hole (1021) adapted to the first locking hole (1015), and the plurality of pressure strips (102) being mounted on the plurality of supporting ribs (1014) in a one-to-one correspondence; A plurality of fixing members (103), each of the fixing members (103) sequentially passes through a corresponding second locking hole (1021) and a first locking hole (1015), fixes the plurality of pressure strips (102) and the rotor bracket (101) together, and respectively restricts the plurality of stepped composite magnetic poles (100) within the plurality of magnetic pole mounting grooves (1012).

6. The rotor according to claim 5, characterized in that Along the radial direction of the rotor support (101), each of the magnetic pole mounting slots (1012) comprises a plurality of interconnected sub-slot segments (11), and the sizes of the plurality of sub-slot segments (11) correspond one-to-one to the sizes of the plurality of composite sub-magnetic poles (1001) of the stepped composite magnetic pole (100); Along the axial direction of the rotor support (101), each sub-slot segment (11) comprises a first slot segment (12) and a second slot segment (13) which are connected; the width of the first slot segment (12) is greater than the width of the second slot segment (13), so as to form two slot shoulders (1013) on both sides of each sub-slot segment (11) which respectively stop and cooperate with two second pole shoes (10032) of the composite sub-pole (1001); Each of the support ribs (1014) is arranged in a sawtooth shape; each of the pressure strips (102) is arranged in a sawtooth shape; Along the circumference of the rotor support (101), the width of the pressure strip (102) is greater than the width of the supporting rib (1014), so as to form two stop sections on both sides of the pressure strip (102) that respectively stop and cooperate with the two first pole shoes (10031) of the composite sub-pole (1001).

7. The rotor according to claim 5, characterized in that Along the radial direction of the rotor support (101), each of the support ribs (1014) is provided with a plurality of first locking holes (1015) at intervals; Each of the pressure strips (102) is a flat structure, and each of the pressure strips (102) is provided with a plurality of second locking holes (1021) at intervals, and the plurality of second locking holes (1021) correspond one-to-one to the plurality of first locking holes (1015), and each of the pressure strips (102) is mounted on the rotor bracket (101) via a plurality of fixing members (103); The pressure strip (102) is made of non-magnetic conductive material; The rotor support (101) is made of a non-magnetic high-strength material.

8. The rotor according to claim 5, characterized in that The permanent magnets (1002) in the plurality of composite sub-magnetic poles (1001) in each stepped composite magnetic pole (100) have the same magnetic properties; and along the circumferential direction of the rotor support (101), the permanent magnets (1002) in two adjacent stepped composite magnetic poles (100) have opposite magnetic properties.

9. The rotor according to claim 5, characterized in that The number of magnetic poles is an even number and can be divided by 4; the permanent magnets (1002) in the multiple composite sub-poles (1001) in each stepped composite magnetic pole (100) have the same magnetic properties; two adjacent stepped composite magnetic poles (100) with the same magnetic properties form a group of magnetic poles, constituting an N pole or an S pole; and multiple groups of magnetic poles are arranged on the rotor bracket (101) along the circumference of the rotor bracket (101), the magnetic properties of two adjacent groups of magnetic poles are opposite, and the N poles and the S poles are arranged alternately.

10. An axial flux permanent magnet motor, characterized in that: The axial flux permanent magnet motor comprises a rotor (1), a stator (2), a rotating shaft (3), a bearing (4) and a base (6); the stator (2) comprises a first stator (21) and a second stator (22); the rotor (1) is fixedly connected to the rotating shaft (3); the two bearings (4) are respectively sleeved at two ends of the rotating shaft (3); the rotating shaft (3) is rotatably mounted on the base (6) via the two bearings (4); along the axial direction of the rotating shaft (3), the first stator (21) and the second stator (22) are mirror-imaged on both sides of the rotor (1) and are respectively fixed to the base (6). On the seat (6), there is an axial gap (5) between the rotor (1) and the first stator (21) and the second stator (22), and the rotor (1) and the stator (2) can rotate relative to each other; the first stator (21) and the second stator (22) both include a stator core (201) and a multi-phase AC winding (202), the stator core (201) includes stator teeth (2011) and stator slots (2012), and the multi-phase AC winding (202) is embedded in the stator slots (2012); wherein the rotor (1) is the rotor according to any one of claims 5 to 9.

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