WO2013107127A1

WO2013107127A1 - Segmented permanent-magnet synchronized motor rotor structure

Info

Publication number: WO2013107127A1
Application number: PCT/CN2012/074753
Authority: WO
Inventors: 方攸同; 马子魁; 卢琴芬; 黄晓艳; 马吉恩; 张建承; 陈威
Original assignee: 浙江大学
Priority date: 2012-01-22
Filing date: 2012-04-26
Publication date: 2013-07-25
Also published as: CN102545435A; CN102545435B

Abstract

A rotor structure of a segmented permanent-magnet synchronized motor, comprising a rotary shaft (10), a rotor iron core (15), a permanent magnet (13), a rotor pole shoe (14), a front end plate (11), and a rear end plate (12). The two end plates have arranged therebetween multiple rotor spacers (16). The rotor spacers separate a rotor into multiple rotor units. Two end faces of the pole shoe in each rotor unit respectively are tightly affixed to the end faces of adjacent rotor spacers. The pole shoe in each rotor unit corresponds to the permanent magnet. The rotor spacers are provided thereon with through holes allowing for penetration by the permanent magnet. The front end plate, the rotor pole shoe, the rotor spacers, and the rear end plate are penetrated with pole shoe-tightening bolts. The pole shoe-tightening bolts tighten in the axial direction the rotor pole shoe and the rotor spacers between the front end plate and the rear end plate. Corners of the through holes of the rotor spacers are arc transitions. The permanent magnet and permanent-magnet through holes on the rotor spacers are provided therebetween with gaps. The present rotor structure has great mechanical strength and is applicable in high-speed rotary motors.

Description

Instruction manual

Segmented permanent magnet synchronous motor rotor structure

Technical field

The invention relates to a rotor structure of a radial permanent magnet synchronous motor, in particular to a permanent magnet built-in segmented permanent magnet synchronous motor rotor for a high speed railway train permanent magnet traction motor.

Background technique

The motor is an electromagnetic device that converts mechanical energy and electrical energy into each other by using a magnetic field as a medium. In order to establish the air gap magnetic field necessary for electromechanical energy conversion inside the motor, there are two methods. One is to generate a magnetic field through a current in the windings of the motor, such as a common DC motor and motor. Such an electrically excited motor requires both specialized windings and corresponding devices, as well as constant supply of energy to maintain current flow. The other is the generation of a magnetic field by permanent magnets. Due to the inherent characteristics of permanent magnet materials, after pre-magnetization (magnetization), no additional energy is required to establish a magnetic field in the surrounding space, a so-called permanent magnet motor.

Compared with the traditional excitation motor, the permanent magnet motor has the characteristics of simple structure, low loss, high power factor, high efficiency, high power density, large starting torque, low temperature rise and light weight. With the continuous improvement and perfection of the magnetic properties of rare earth permanent magnet materials (especially NdFeB permanent magnet materials) and the gradual reduction of prices, the research and development of permanent magnet motors has gradually matured, making permanent magnet motors in national defense, industrial and agricultural production and daily life. And other aspects have gained more and more applications.

A permanent magnet motor is a motor that generates a magnetic field by means of a permanent magnet mounted on a rotor. The stator structure is basically the same as that of a conventional synchronous/asynchronous motor, that is, a stator core composed of a laminated silicon steel sheet and a stator coil embedded in a stator core slot. And a three-phase alternating current is generated to generate a rotating magnetic field in the stator coil. The rotor of the permanent magnet motor is mainly composed of the rotor core and the permanent magnet. This is the main difference between the permanent magnet motor and other types of motors. The rotor magnetic circuit structure is the key technology of the permanent magnet motor. The rotor uses different magnetic circuit configurations, and the motor's operating performance, control strategy, manufacturing process, and use are also different.

According to the difference of the mounting position of the permanent magnet on the permanent magnet motor rotor, the rotor magnetic circuit of the permanent magnet motor can be generally divided into three types: surface type, built-in type and claw pole type. The surface rotor magnetic circuit has a simple structure and low manufacturing cost, but the rotor winding cannot be mounted on the rotor surface, so the permanent magnet motor has no asynchronous starting capability, and the mechanical strength of the rotor is poor, and the permanent magnet is prone to breakage at high rotation speed. . The permanent magnet of the built-in permanent magnet motor rotor is located inside the rotor. According to the relationship between the magnetization direction of the permanent magnet and the rotation direction of the rotor, the built-in rotor magnetic circuit structure can be divided into three types: radial type, tangential type and hybrid type. Compared with the surface rotor, the built-in permanent magnet motor rotor can protect the permanent magnet with relatively low mechanical properties, and can significantly increase the size of the permanent magnet according to the performance of the permanent magnet motor. Therefore, it is the permanent magnet motor rotor. A structure that is widely used at present.

At present, the conventional segmented permanent magnet motor rotors mostly use rotor bars to reinforce the rotor, but there are still problems such as low mechanical strength, poor reliability, serious eddy current loss on the rotor surface, and significant internal magnetic leakage, thus hindering high power and high. The development of rotational speed and large-slewing-diameter permanent magnet motors has limited the application of permanent magnet motors as traction motors on high-speed trains.

Chinese Patent Application No. 201010513307.3 discloses a high-power permanent magnet motor rotor, which adopts a permanent magnet embedded structure, the rotor is composed of at least two rotor units in the axial direction, and the iron core between adjacent two pole permanent magnets of each rotor unit The upper opening is provided with a magnetic isolation groove along the axial direction of the rotor, and a partition plate made of a non-magnetic material is arranged between adjacent rotor units, and end plates are arranged at both ends of the rotor unit, and at least two rotor units are axially positioned. Tighten the bolts to secure them. The permanent magnet motor rotor has the following disadvantages: 1. The centrifugal force of the rotor pole piece is shared by the end plate, the partition plate and the positioning tension bolt, that is to say, the positioning of the fixed rotor unit tension bolt needs to bear the bending moment, when the rotor When rotating at high speed, the centrifugal force is large, and it is easy to cause the positioning tension bolt to be bent by centrifugal force, that is, the rotor is not suitable for a motor that rotates at a high speed. 2. Although a magnetic isolation groove is provided in the core, the core between the adjacent permanent magnets still has a connecting portion, and the magnetic fields of the permanent magnets of the adjacent two poles are easily connected to each other through the core portion between the permanent magnets to cause magnetic leakage. That is to say, the structure cannot avoid magnetic flux leakage and the magnetic flux leakage is severe. 3. The partition plate is disposed between two adjacent rotor units, the thickness of the partition plate occupies the effective length of the rotor along the axial direction; when the rotor adopts a large number of rotor units and the rotor diaphragm is thick, the rotor The effective length will be drastically reduced, thereby affecting the electromagnetic performance of the rotor.

Summary of the invention

In order to overcome the above disadvantages of the prior art, the present invention provides a segmented permanent magnet synchronous motor rotor structure having high mechanical strength and suitable for a high speed rotating electrical machine.

The segmented permanent magnet synchronous motor rotor structure comprises a rotating shaft, a rotor core fixed to the rotating shaft, a permanent magnet sleeved outside the rotor core, and a rotor pole piece which is located outside the permanent magnet for reasonably distributing the magnetic field and protecting the permanent magnet , and the front end plate and the rear end plate respectively located at both ends of the rotor core;

The utility model is characterized in that: a plurality of rotor baffles made of non-magnetic material are arranged between the two end plates, the rotor pole pieces are independent of each other, and the rotor pole piece and the rotor baffle are axially spaced apart, the rotor baffle Separating the rotor into a plurality of rotor units in the axial direction, wherein the two end faces of the rotor pole pieces in each rotor unit are respectively in contact with the end faces of the adjacent rotor baffles, and the rotor pole pieces in each rotor unit correspond to the permanent magnets; The rotor baffle is provided with a through hole for allowing the permanent magnet to penetrate, the front end plate, the rotor pole piece, the rotor baffle plate and the rear end plate penetrate the pole piece tensioning bolt, and the pole piece tightening bolt axially locks the left rear end plate a rotor pole piece and a rotor diaphragm between the left rear plate and the left rear plate;

An arc transition is made at the corner of the through hole of the rotor spacer to reduce the stress concentration at the corner, and there is a gap between the permanent magnet and the permanent magnet through hole on the rotor spacer.

The permanent magnet between each rotor pole piece and the rotor core may be a single piece, or a plurality of permanent magnets may be spliced along the axial direction of the rotor. When there are a plurality of permanent magnets between the rotor pole piece and the rotor core, each of the through holes corresponds to one permanent magnet, and a spacer is arranged between the adjacent through holes, and a corner of each of the permanent magnet through holes Arc transitions are used to reduce stress concentrations.

Further, the rotor baffle is provided with a weight reducing hole for reducing the weight of the baffle and reducing the stress concentration, and each of the permanent magnet through holes is distributed with a plurality of weight reducing holes, and a plurality of weight reducing holes around the same permanent magnet form one The weight loss group and the weight loss group are symmetrically distributed. The lightening hole is a circular hole or a waist hole or a polygonal hole whose corner is an arc transition, and the weight reducing hole is mainly concentrated at a corner of the permanent magnet through hole.

Further, the rotor pole piece is a laminated pole piece, the rotor core is a laminated core, and the rotor baffle and the rotor core are provided with iron tension bolts axially locking the rotor core and the rotor partition, two of the rotor cores The end faces are respectively adjacent to the adjacent two rotor partitions;

The two end faces of the rotor pole piece respectively abut the two adjacent rotor baffles, and the two ends of the lower end of the rotor pole piece near the rotor core are respectively provided with a downwardly extending first flange group, and the rotor core is close to the rotor pole The upper edge of the upper edge of the shoe is respectively provided with an upwardly extending second flange group, and the first flange group and the second flange group limit the permanent magnet between the rotor pole piece and the rotor core.

Further, each of the rotor spacers is formed by laminating a plurality of separator sheets.

Further, the two ends of the pole shoe tightening bolt are respectively provided with a pole piece tensioning nut, and the pole piece tensioning nut is closely attached to the rotor pole piece at both ends; the two ends of the pole piece tightening bolt are respectively provided with fixing screw holes, the front end plate and The rear end plates are respectively connected to the pole piece tension bolts by screws, and the screws are engaged with the fixing screw holes.

The technical idea of the present invention is: dividing the rotor structure into a plurality of rotor units by a rotor partition along the axial direction of the rotor structure, and the rotor pole pieces of adjacent rotor units are magnetically separated by the rotor diaphragm, in the same rotor unit, the rotor The pole shoes are independent of each other and do not communicate with each other, thereby avoiding the occurrence of magnetic leakage. The rotor structure is locked by the pole shoe tightening bolt and the iron core tightening bolt, and the two end faces of the rotor pole piece are respectively adhered to the two rotor diaphragms, and the rotor structure is overcome by the friction between the rotor pole piece and the rotor diaphragm. The centrifugal force of the rotor pole piece and the permanent magnet when rotating at high speed; the two end faces of the rotor core are closely attached to the two rotor diaphragms respectively, and the friction between the rotor core and the rotor diaphragm also overcomes the rotor pole when the rotor structure rotates at a high speed. The centrifugal force exerted by the shoe and the permanent magnet; at the same time, between the laminations of the rotor core, between the laminations of the rotor pole piece and between the rotor baffles The plate laminations also rely on mutual friction to overcome the centrifugal force. The friction between the rotor pole piece and the rotor diaphragm is adjusted by adjusting the locking force of the pole piece tightening bolt. The pole piece tensioning bolt only needs to bear the axial pulling force without suffering the bending moment due to the centrifugal force. The shoe tightening bolt is not easily broken, and the rotor structure has a long service life.

The beneficial effects of the invention are as follows: 1. By relying on the friction between the rotor pole piece and the diaphragm to overcome the centrifugal force when the rotor structure rotates, the bolt is not subjected to bending moment and is not easily broken, and the service life of the rotor structure is long. 2. The permanent magnet and the rotor core respectively pass through the rotor diaphragm, that is, the thickness of the rotor diaphragm does not occupy the axial length of the rotor structure. 3. The rotor pole pieces are independent of each other to avoid magnetic leakage.

DRAWINGS

Figure 1 is a schematic exploded view of a segmented permanent magnet motor rotor component.

Figure 2 is a schematic diagram of the magnetic field analysis of the rotor and stator of a segmented permanent magnet motor.

Figure 3 is a schematic view of a first segmented permanent magnet motor rotor diaphragm.

Figure 4 is a schematic view showing the assembly of the first segmented permanent magnet motor rotor spacer and permanent magnet.

Figure 5 is a schematic view of a second segmented permanent magnet motor rotor diaphragm.

Figure 6 is a schematic view of a third segmented permanent magnet motor rotor diaphragm.

Figure 7 is a schematic view of a fourth segmented permanent magnet motor rotor diaphragm.

Fig. 8 is a schematic view showing the state of separation of the rotor pole piece and the rotor core of the segmented permanent magnet motor.

Figure 9 is an exploded perspective view of the segmented permanent magnet motor rotor component when a fourth spacer is used.

Fig. 10 is an exploded perspective view showing the segmented permanent magnet motor rotor permanent magnet, the rotor pole piece and the rotor spacer when the fourth spacer is used.

Fig. 11 is a view showing the mutual cooperation of the segmented permanent magnet motor rotor shaft with the rotor core and the rotor spacer when the fourth spacer is used.

Fig. 12 is a schematic view showing the assembly of the rotor pole piece and the rotor core and the rotor spacer in a state in which the segmented permanent magnet motor rotor is in a separated state when the fourth spacer is used.

Figure 13 is a schematic diagram of the assembly of the segmented permanent magnet motor rotor.

detailed description

Embodiment 1

Refer to Figure 1-5

As shown in FIG. 1, the segmented permanent magnet synchronous motor rotor structure includes a rotating shaft 10, a rotor core 15 fixed to the rotating shaft 10, and a permanent magnet 13 sleeved outside the rotor core 15, which is located outside the permanent magnet 13 for rationally distributing the magnetic field. a rotor pole piece 14 for protecting the permanent magnet 13, and a front end plate 11 and a rear end plate 12 respectively located at the two ends of the rotor core 15;

A plurality of rotor baffles 16 made of a non-magnetic material are disposed between the two end plates 11, 12, and the rotor pole pieces 14 are independent of each other, and the rotor pole pieces 14 and the rotor baffle 16 are axially spaced apart. The rotor baffle 16 divides the rotor axially into a plurality of rotor units, and the two end faces of the rotor pole piece 14 in each rotor unit are respectively in close contact with the end faces of the adjacent rotor baffles 16, and the rotor poles in each rotor unit The shoe 14 corresponds to the permanent magnet 13; the rotor diaphragm 16 is provided with a through hole allowing the permanent magnet 13 to penetrate, and the front end plate 11, the rotor pole piece 14, the rotor partition 16 and the rear end plate 12 are inserted through the pole piece tensioning bolt 23 , the pole shoe tightening bolt 23 axially locks the rotor pole piece 14 and the rotor diaphragm 16 between the left rear end plates 11 , 12 and the left rear end plates 11 , 12 ;

An arc transition is made at the corner of the through hole of the rotor spacer 16 to reduce the stress concentration at the corner, and there is a gap between the permanent magnet 13 and the permanent magnet through hole on the rotor spacer 16.

The two-dimensional magnetic circuit analysis of the permanent magnet motor rotor is shown in Fig. 3. The magnetic field flux (magnetic line) of the motor circulates according to the following path. The magnetic field lines start from the N pole of the current permanent magnet 13A, enter the air gap 28 through the rotor pole piece 14A, and then enter the stator through the stator teeth 262. In the stator, along the stator yoke 261 to the region corresponding to the adjacent poles, the air gap is entered from the stator teeth. Then, the adjacent rotor pole pieces 14B enter the S pole of the adjacent permanent magnet 13B, and then enter the rotor core 15 from the N pole. Finally, return to the N pole of the current permanent magnet 13A to form a magnetic line circuit.

As shown in FIG. 1, in order to overcome the strong centrifugal force received by the large-diameter permanent magnet motor rotor pole piece 14 and the permanent magnet 13 under high-speed operating conditions, the rotor pole piece 14 and the rotor core 15 are divided into specific lengths along the rotor axis. Several subsections. As shown in Figure 1, the rotor spacer 16 is inserted between the axially adjacent rotor pole piece 14 and the rotor core 15 subsection, even if the rotor pole piece 14, The rotor core 15 and the rotor diaphragm 16 are sequentially spaced, and the friction between the rotor diaphragm 16 and the rotor pole piece 14 balances the centrifugal force experienced by the rotor pole piece 14 and the permanent magnet 13 as the rotor rotates. Since the rotor core 15 is fixed above the rotor shaft 10, the centrifugal force received by the rotor core 15 is received by the rotor shaft 10. In order to meet the mechanical strength, stiffness and life requirements of the rotor and to fully utilize the mechanical properties of the material of the rotor diaphragm 16, the finite element calculation method can be used to obtain the optimum thickness values of the rotor pole piece 14 and the rotor diaphragm 6. Since the rotor diaphragm 16 is made of a non-magnetic material (such as high-strength aluminum alloy, carbon fiber, ceramics, etc.) or a low-permeability material (such as high-strength austenitic stainless steel, titanium alloy), it is inserted along the axial direction of the rotor. The rotor diaphragm 16 does not cause a magnetic leakage problem and does not significantly affect the magnetic properties of the rotor.

The permanent magnet 13 between each of the rotor pole pieces 14 and the rotor core 15 may be a single piece or a plurality of permanent magnets 13 which are axially joined together along the rotor. When there are a plurality of permanent magnets 13 between the rotor pole piece 14 and the rotor core 15, each of the through holes corresponds to a permanent magnet 13 on the rotor partition 16 respectively, and a spacer is arranged between adjacent through holes, and each permanent magnet Arc transitions are used at the corners of the through holes to reduce stress concentration, as shown in Figure 5.

The rotor diaphragm 16a is made of a non-magnetic material (such as high-strength aluminum alloy, carbon fiber, ceramics, etc.) or a low-permeability material (such as high-strength austenitic stainless steel, titanium alloy) for bearing the rotor at high speed. The centrifugal force received by the rotor pole piece 14 and the permanent magnet 13 when rotated. The rotor diaphragm 16 includes a through hole 165 for achieving radial and axial positioning of the permanent magnet 13 with respect to the rotor shaft 10, and a circular hole 161 for receiving the pole piece tensioning bolt 23 for receiving the core tension bolt A circular hole 162 of 24, which cooperates with the outer surface of the rotor shaft 10 for a central circular hole 163 for the radial positioning of the rotor diaphragm 16 with respect to the rotor shaft 10, the keyway 164 mating with a key 25 above the rotor shaft 10 for The rotor diaphragm 16 is positioned circumferentially relative to the rotor shaft 10.

The structure of the first type of rotor spacer 16a is as shown in Fig. 3; the through hole 165 of the rotor spacer 16a for accommodating the permanent magnet 13 is formed by a special-shaped hole, and the permanent magnet between the rotor pole piece and the rotor core is a single magnet. The inner side surfaces 163a and 164a of the permanent magnet through hole 161 of the rotor spacer 16a abut against the surfaces 133a and 131a of the permanent magnet 13a, respectively, thereby achieving radial positioning of the permanent magnet 13a with respect to the rotor shaft 10, the rotor spacer The inner side faces 161a and 162a of the plate 16a abut against the side faces 132a of the permanent magnets 13a, respectively, thereby achieving circumferential positioning of the permanent magnets 13a with respect to the rotor shaft 10, as shown in FIG.

The structure of the second rotor diaphragm 16b is as shown in Fig. 5. The rotor pole piece and the rotor core are formed by splicing two permanent magnets along the axial direction of the rotor. The inner sides 163b and 164b of the rotor diaphragm 16b are used to achieve radial positioning of the permanent magnet 13 relative to the rotor shaft 10, and the inner sides 162b and 165b are used to achieve circumferential positioning of the permanent magnet 13 relative to the rotor shaft 10, the keyway 164 and the inner circle The holes 163 are used to achieve circumferential and radial positioning of the rotor diaphragm 16b relative to the rotor shaft 10, respectively. The through hole for accommodating the permanent magnet 13 has two sides 161b on one side and a straight side 165b on the other side.

In addition, a thermosetting polymer material such as FRP or epoxy resin may be filled in the gap between the permanent magnet motor rotor pole piece 14 and the rotor diaphragm 16 to prevent the motor from vortexing due to uneven rotor surface during high speed operation. The air resistance of the permanent magnet motor rotor during high-speed operation is reduced, and the debris generated by the collapse of the permanent magnet 13 is prevented from falling into the air gap between the rotor and the stator of the permanent magnet motor, thereby avoiding unnecessary mechanical failure. .

The technical idea of the present invention is: dividing the rotor structure into a plurality of rotor units by the rotor partition 16 along the axial direction of the rotor structure, and the rotor pole pieces 14 of the adjacent rotor units are magnetically separated by the rotor partition 16, the same rotor unit Inside, the rotor pole pieces 14 are independent of each other and do not communicate with each other, thereby avoiding the occurrence of magnetic leakage. The rotor structure relies on the pole piece to tighten the bolt 23 and iron The core tension bolts 24 are locked, and the two end faces of the rotor pole piece 14 respectively abut against the two rotor partitions 16, relying on the friction between the rotor pole piece 14 and the rotor partition 16 to overcome the rotor rotation of the rotor structure at a high speed. The centrifugal force of the pole piece 14 and the permanent magnet 13 is received; the two end faces of the rotor core 15 are respectively in close contact with the two rotor baffles 16, and the friction between the rotor core 15 and the rotor baffle 16 is also overcome when the rotor structure is rotated at a high speed. The centrifugal force applied to the rotor pole piece 14 and the permanent magnet 13; at the same time, the mutual friction between the laminations of the rotor core 15 and the laminations of the rotor pole piece 14 and the separator laminations of the rotor diaphragm 16 To overcome the centrifugal force. The friction between the rotor pole piece and the rotor baffle is adjusted by adjusting the locking force of the pole piece tightening bolt, and the pole piece tightening bolt 23 only needs to bear the axial pulling force without suffering the bending moment due to the centrifugal force. The pole shoe tightening bolt 23 is not easily broken, and the rotor structure has a long service life.

Embodiment 2

Refer to Figure 6-12

The difference between this embodiment and the first embodiment is that the rotor partition 16 is provided with a lightening hole. The rotor baffle 16 is provided with a weight reducing hole 166 for reducing the weight of the baffle and reducing the stress concentration. Each of the permanent magnet through holes 165 is distributed with a plurality of lightening holes 166, and a plurality of weight reducing around the same permanent magnet 13 The holes 166 form a group of lightening holes, and the groups of weight reducing holes are symmetrically distributed. The lightening hole 166 is a circular hole or a waist hole or a polygonal hole whose corner is an arc transition, and the weight reducing hole 166 is mainly concentrated at the corner of the permanent magnet through hole. One one one

The structure of the third type of rotor spacer 16c is as shown in Fig. 6. The inner side faces 163c and 164c of the permanent magnet through holes of the rotor spacer 16c serve to achieve radial positioning of the permanent magnet 13 with respect to the rotor shaft 10, and the inner side surface 165c is used for The circumferential positioning of the permanent magnet 13 with respect to the rotor shaft 10 is achieved, and the keyway 164 and the inner circular hole 163 are respectively used to achieve circumferential and radial positioning of the rotor diaphragm 16c with respect to the rotor shaft 10. The weight reducing hole of the rotor spacer 16c includes a circular hole and a polygonal hole whose corner is an arc transition, and the weight reducing hole 166 is distributed on the side of the permanent magnet through hole close to the rotor core 15.

The structure of the fourth rotor spacer 16d is as shown in Fig. 7, the inner side surface 163d of the permanent magnet through hole of the rotor spacer 16d and

164d is used to achieve radial positioning of the permanent magnet 13 relative to the rotor shaft 10, the inner side surface 165d is used to achieve circumferential positioning of the permanent magnet 13 relative to the rotor shaft 10, and the inner circular arcs 166d, 167d and 168d are all set for reducing stress concentration. Transition arc. Keyway 164 and inner circular aperture 163 are used to achieve circumferential and radial positioning of rotor diaphragm 16d relative to rotor shaft 10, respectively. The weight reducing hole of the rotor spacer 16d includes a circular hole and a polygonal hole whose corner is an arc transition, and the weight reducing hole 166 is distributed on the side of the permanent magnet through hole close to the rotor core 15.

The rotor pole piece 14 is a laminated pole piece, the rotor core 15 is a laminated core, and the rotor partition 16 and the rotor core 15 are provided with an iron tension bolt 24 axially locking the rotor core 15 and the rotor partition 16 . The two end faces of the rotor core 15 are respectively in close contact with the adjacent two rotor spacers 16.

The rotor pole piece 14 is formed by laminating a ferromagnetic material sheet with good magnetic permeability (such as a silicon steel sheet having a thickness of 0.2 to 0.5 mm) for rationally distributing the rotor magnetic field and protecting the permanent magnet 13 from being prevented. The permanent magnet 13 is broken by centrifugal force. The rotor core 15 is formed by laminating a sheet-like ferromagnetic material sheet (e.g., a silicon steel sheet having a thickness of 0.2 to 0.5 mm) having the same magnetic permeability as the rotor pole piece 14. The cross-sectional structure of the rotor pole piece 14 and the rotor core 15 is as shown in Fig. 8. Above the rotor pole piece 14, eight circular holes 146 are provided for receiving the pole piece tensioning bolts 23, which are used to achieve circumferential and radial positioning of the permanent magnets 13 relative to the rotor shaft 10, respectively. Above the rotor core 15, four circular holes 155 are provided for receiving the core tension bolts 24, and the central circular holes 153 are engaged with the outer surface of the rotor shaft 10 for radial positioning of the rotor core 15 with respect to the rotor shaft 10, the keyway The 154 cooperates with a key 25 (shown in Figure 11) above the rotor shaft 10 for circumferential positioning of the rotor core 15 relative to the rotor shaft 10.

As shown in FIG. 8, the two end faces of the rotor pole piece 14 respectively abut the adjacent two rotor partitions 16, and the two ends of the lower end of the rotor pole piece 14 near the rotor core 15 are respectively provided with a downwardly extending first Flange set 141, rotor core 15 close to the rotor The upper edge of the pole piece 14 is respectively provided with an upwardly extending second flange group 151, and the first flange group 141 and the second flange group 151 restrict the permanent magnet 13 between the rotor pole piece 14 and the rotor core 15 . There is a gap 145 between the first flange set 141 and the second flange set 151, so that the rotor pole piece 14 and the rotor core 15 are independent of each other, and magnetic leakage does not occur. Each of the rotor spacers 16 is formed by laminating a plurality of separator sheets.

By providing a weight reducing hole in the rotor spacer, not only the weight of the rotor structure can be reduced, but also the stress concentration caused by the permanent magnet pressing the rotor diaphragm during rotation can be reduced.

Embodiment 3

Refer to Figure 13

The difference between the embodiment and the second embodiment is that: the pole shoe tensioning bolt 23 is respectively provided with a pole piece tensioning nut 20, and the pole piece tensioning nut 20 is closely attached to the rotor pole piece 14 at both ends; The two ends of the tightening bolt 20 are respectively provided with fixing screw holes, and the front end plate 11 and the rear end plate 12 are respectively connected to the pole piece tightening bolts 23 by screws 18, and the screws 18 are engaged with the fixing screw holes. The rest of the structure is the same.

The rotor front end plate 11 and the rear end plate 12 are made of a thick non-magnetic material (such as high-strength aluminum alloy) plate or a low magnetic permeability material (such as high-strength austenitic stainless steel) plate, not only for the rotor pole piece 14, The rotor diaphragm 16 and the permanent magnet 13 have a stabilizing effect, and can also serve as a deduplication structure for dynamic balance correction of the permanent magnet motor rotor. The front end plate fastening bolt 17 is coupled to the internally threaded hole 233 at the front end of the pole piece tensioning bolt 23 by an external thread, so that the rotor front end plate 11 is coupled with the pole piece tensioning bolt 23, thereby making the inner side surface of the rotor front end plate 11 112 abuts against the front side 147 of the rotor pole piece 14 at the front end of the rotor. The outer surface of the rear end of the pole shoe tightening bolt 23 is provided with an external thread 232, and the external thread 232 is coupled with the pole piece tightening bolt nut 20 to secure the rotor pole piece 14 and the rotor diaphragm 16. A lock washer 22 is placed between the pole shoe tension bolt nut 20 and the rear side surface 148 of the rotor pole piece 14 at the rear end of the rotor, preventing the pole shoe from tightening the bolt nut 20 and tightening on the pole piece. The external thread 232 of the bolt 23 is coated with a metal glue in the threaded engagement of the pole piece tension bolt nut 20 to achieve a firm coupling therebetween. The rear end plate fastening bolt 18 is coupled to the internally threaded hole 231 at the rear end of the pole piece tensioning bolt 23 by an external thread to couple the rotor rear end plate 12 with the pole piece tensioning bolt 23, thereby causing the rotor rear end plate 12 The inner side 121 then abuts against the rear side surface 148 of the rotor pole piece 14 at the rear end of the rotor. As shown in FIGS. 1 and 6, a small gap is left between the inner hole 111 of the rotor front end plate 11 and the collar 102 of the rotor shaft 10, preventing the front end plate 11 and the rotor shaft 10 from being assembled in the rotor. Interference occurs.

The content described in the embodiments of the present specification is merely an enumeration of the implementation forms of the inventive concept, and the scope of the present invention should not be construed as being limited to the specific forms stated in the embodiments. The scope of the present invention also belongs to the technical field. Equivalent technical means that a person can think of in accordance with the inventive concept.

Claims

Claim

1. The rotor structure of the segmented permanent magnet synchronous motor comprises a rotating shaft, a rotor core fixed to the rotating shaft, a permanent magnet sleeved outside the rotor core, and a rotor located outside the permanent magnet for reasonably distributing the magnetic field and protecting the permanent magnet a pole piece, and a front end plate and a rear end plate respectively located at both ends of the rotor core;

The utility model is characterized in that: a plurality of rotor baffles made of non-magnetic material are arranged between the two end plates, the rotor pole pieces are independent of each other, and the rotor pole piece and the rotor baffle are axially spaced apart, the rotor baffle Separating the rotor into a plurality of rotor units in the axial direction, wherein the two end faces of the rotor pole pieces in each rotor unit are respectively in contact with the end faces of the adjacent rotor baffles, and the rotor pole pieces in each rotor unit correspond to the permanent magnets; The rotor baffle is provided with a through hole for allowing the permanent magnet to penetrate, the front end plate, the rotor pole piece, the rotor baffle and the rear end plate are penetrated by the pole piece tightening bolt, and the pole piece tightening bolt axially locks the left rear end plate a rotor pole piece and a rotor diaphragm between the left rear plate and the left rear plate;

The corner of the through hole of the rotor baffle is an arc transition, and there is a gap between the permanent magnet and the permanent magnet through hole on the rotor baffle.

2. The segmented permanent magnet synchronous motor rotor structure according to claim 1, wherein: the rotor baffle is provided with a weight reducing hole for reducing the weight of the baffle and reducing stress concentration, and each of the permanent magnet through holes is surrounded by A plurality of lightening holes are distributed, and a plurality of weight reducing holes around the same permanent magnet form a weight reducing hole group, and the weight reducing hole groups are symmetrically distributed. The lightening hole is a circular hole or a waist hole or a polygonal hole whose corner is an arc transition, and the weight reducing hole is mainly concentrated at a corner of the permanent magnet through hole.

3. The segmented permanent magnet synchronous motor rotor structure according to claim 1 or 2, wherein: the rotor pole piece is a laminated pole piece, the rotor core is a laminated core, the rotor partition and the rotor core a core tensioning bolt with an axial locking rotor core and a rotor partition, the two end faces of the rotor core are respectively adjacent to the adjacent two rotor partitions;

The two end faces of the rotor pole piece are respectively adjacent to the adjacent two rotor partitions, and the rotor pole piece is close to the rotor The two ends of the lower edge of the core are respectively provided with a first flange group extending downward, and the two ends of the upper edge of the rotor core near the rotor pole piece are respectively provided with an upwardly extending second flange group, the first flange group and the first flange group The two flange sets constrain the permanent magnet between the rotor pole piece and the rotor core.

4. The segmented permanent magnet synchronous motor rotor structure according to claim 1, wherein each of the rotor spacers is formed by laminating a plurality of separator laminations.

5. The segmented permanent magnet synchronous motor rotor structure according to claim 1, wherein: the pole shoe tensioning bolt is respectively provided with a pole piece tensioning nut at both ends thereof, and the pole piece tensioning nut is closely attached to the rotor at both ends. The pole piece is provided with fixing screw holes at both ends of the pole shoe tightening bolt, and the front end plate and the rear end plate are respectively connected with the pole piece tightening bolt by screws, and the screw engages with the fixing screw hole.