CN114400805A - Rotor structure of permanent magnet synchronous motor - Google Patents

Abstract

The invention discloses a rotor structure of a permanent magnet synchronous motor, comprising: a rotating shaft, the rotating shaft rotates around the axis; a rotor iron core, the rotor iron core is sleeved on the outside of the rotating shaft; a permanent magnet group, the permanent magnet group is arranged outside the rotor iron core; A filler, the filler is arranged on the outside of the rotor core, and a chute is formed between the filler and the permanent magnet group; a composite sheath, the composite sheath is sleeved on the outer side of the permanent magnet group and the filler, and the composite sheath includes: heat conduction layer, the heat-conducting layer is arranged by wrapping the permanent magnet group and the filler; the sheath ring, the sheath ring is wrapped around the outer side of the heat-conducting layer at intervals along the axis direction. The invention mainly solves the problem of difficult heat dissipation of the rotor of the traditional permanent magnet synchronous motor.

Description

Rotor structure of a permanent magnet synchronous motor

technical field

The present invention relates to the technical field of motors, and more particularly, to a rotor structure of a permanent magnet synchronous motor.

Background technique

In the prior art, the special application of high-speed permanent magnet synchronous motor in industry has attracted attention, and high-speed permanent magnet synchronous motor has become an indispensable technology, especially in high-capacity compact systems, such as machine tool spindle drives. , turbo compressors and micro-turbines, high-speed permanent magnet motors can be directly coupled to the drive or turbine without the need for a separate mechanical gear for high rotational torque.

However, due to the mechanical stress caused by the high-speed rotation of the rotor in the motor and the power loss caused by the high-frequency input power, it is necessary to improve the control, bearing, heat dissipation and cooling technology, and various electrical and mechanical problems may occur. , directly through axial ventilation, in this way, the rotor is separated from the cooling gas, especially the permanent magnet can only realize the contact between the outer surface and the cooling gas. There are problems such as excessively thick sheath, which greatly increases the eddy current loss and difficulty in heat dissipation of the rotor, and the use of thin sheaths cannot meet the high-strength requirements.

SUMMARY OF THE INVENTION

In order to solve the above technical problems, the present invention provides a rotor structure of a permanent magnet synchronous motor, which can meet the rated operating conditions of the high-speed motor, protect the permanent magnet, and at the same time greatly improve the heat dissipation capacity of the rotor without greatly increasing the rotor eddy current loss.

In order to solve the above-mentioned technical problems, the technical scheme adopted in the present invention is:

A rotor structure of a permanent magnet synchronous motor, comprising:

A rotating shaft, the rotating shaft rotates around an axis;

The rotor iron core is sleeved on the outside of the rotating shaft;

Permanent magnet group, the permanent magnet group is arranged outside the rotor core;

Composite sheath, the composite sheath is sleeved on the outside of the permanent magnet group, and the composite sheath includes:

The thermal conductive layer is arranged by wrapping the permanent magnet group, and the thermal conductive layer is used to conduct heat;

A sheath ring, which is wrapped around the outer side of the heat conduction layer at intervals along the axis direction, and the sheath ring is used to improve the strength of the composite sheath;

The filler, the filler is arranged between the rotor core and the composite sheath, the filler and the permanent magnet group are at least partially adhered, and the abutting place is adjacent to the axial ends of the composite sheath, and the filler and the permanent magnet group are in contact with each other. An inclined slot is formed between the two, the opening direction of the inclined slot is basically parallel to the axis direction, and the inclined slot is used to increase the contact area between the permanent magnet group and the air.

Preferably, the permanent magnet group includes permanent magnets, the shape of the permanent magnets is a sector ring body, and the center of the sector ring body is located on the axis.

Preferably, there are at least two permanent magnets, and the permanent magnets in the permanent magnet group are basically arranged along the axis direction.

Preferably, each permanent magnet in the permanent magnet group is exactly the same, and the permanent magnets in a single permanent magnet group are arranged in a stepped shape, and two inclined slots are formed between the single permanent magnet group and the filler, and the two inclined slots are open. In the opposite direction.

Preferably, the lengths of the permanent magnets in the permanent magnet group are different, and the permanent magnets in a single permanent magnet group are arranged in sequence along the axis direction according to the lengths becoming longer or shorter, and one side of the permanent magnets in the single permanent magnet group is both. Fitted with the filler, the longest permanent magnet in a single permanent magnet group is fitted with another filler.

Preferably, the shape of the filler is a sector ring body, the center of the sector ring body is located on the axis, and the filler is arranged around the axis.

Preferably, the filler includes:

The ventilation channel runs through the filler along the axis direction.

Preferably, the composite sheath further includes:

The annular groove is arranged on the outer side of the heat conduction layer at intervals along the axis direction, and the sheath ring is sleeved in the annular groove.

Preferably, the material of the heat-conducting layer is at least one of iron alloy, aluminum alloy or titanium alloy.

Preferably, the material of the sheath ring is at least one of carbon fiber, Kevlar or nylon.

Compared with the prior art, the present invention at least has the following beneficial effects:

In the rotor structure of a permanent magnet synchronous motor of the present invention, the permanent magnets in the permanent magnet group are arranged in a stepped arrangement, and the fillers are attached to the head and tail permanent magnets in the permanent magnet group, so as to form inclined grooves. The opening of the slot faces the outside of the rotor structure, and the contact area between the permanent magnet and the air is increased, thereby improving the heat dissipation efficiency.

Secondly, in the rotor structure of the present invention, the composite sheath is composed of two materials, which realizes the effect of small thickness and high strength of the composite sheath, and the thickness of the composite sheath is reduced to improve the heat dissipation efficiency of the rotor structure.

In addition, in the rotor structure of the present invention, by setting the filler and the permanent magnet to fit together to avoid the corner puncture of the composite sheath by the permanent magnet, the purpose of protecting the composite sheath is achieved; Heat dissipation; and a ring groove is arranged on the heat conduction layer, and the ring groove is beneficial to fix the sheath ring and prevent the sheath ring from being separated from the heat conduction layer.

Description of drawings

1 is an axial schematic diagram of a rotor structure of a permanent magnet synchronous motor according to the application;

Fig. 2 is the front view of the rotor structure of a kind of permanent magnet synchronous motor of the application;

3 is a top view of a rotor structure of a permanent magnet synchronous motor according to the application;

Fig. 4 is a sectional view along the A-A direction in Fig. 3;

FIG. 5 is a schematic diagram of the axial side after the composite sheath is removed in an implementation manner of the application;

FIG. 6 is a top view of an implementation manner of the application after removing the composite sheath;

7 is a schematic diagram of the axial side after the composite sheath is removed in another implementation manner of the present application;

FIG. 8 is a top view of another implementation manner of the present application after the composite sheath is removed.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

Example 1:

1 to 4 , a rotor structure 100 of a permanent magnet synchronous motor according to this embodiment includes a rotating shaft 11 , a rotor iron core 12 , a permanent magnet group 13 , a filler 14 and a composite sheath 15 . The rotating shaft 11 , the rotor core 12 , the permanent magnet group 13 and the composite sheath 15 are arranged in order from the inside to the outside, and the filler 14 and the permanent magnet group 13 are in the same layer. The rotating shaft 11 rotates around the axis 101; the rotor iron core 12 is sleeved on the outside of the rotating shaft 11; the permanent magnet group 13 is arranged on the outside of the rotor iron core 12; the composite sheath 15 is sleeved on the outside of the permanent magnet group 13, and the composite sheath 15 includes: layer 151 and sheath ring 152, the thermal conductive layer 151 is arranged around the permanent magnet group 13, the thermal conductive layer 151 is used to conduct heat, the sheath ring 152 is spaced around the outer side of the thermal conductive layer 151 along the axis direction, and the sheath ring 152 is used to improve the composite The strength of the sheath 15; the filler 14, the filler 14 is arranged between the rotor core 12 and the composite sheath 15, the filler 14 and the permanent magnet group 13 are at least partially fitted, and the fitting is adjacent to the composite jacket 15. At both ends of the axial direction, and between the filler 14 and the permanent magnet group 13, a chute 16 is formed. The opening direction of the chute 16 is basically parallel to the direction of the axis 101. The chute 16 is used to increase the contact area between the permanent magnet group 13 and the air. .

The rotating shaft 11 rotates around the axis 101 , the rotor core 12 is sleeved on the outside of the rotating shaft 11 , and the rotating shaft 11 drives the rotor core 12 to rotate, that is, the rotor core 12 also rotates around the axis 101 . It can be understood that the shape of the rotating shaft 11 is a cylinder, and the shape of the rotor core 12 is a ring. The ring is sleeved on the outside of the cylinder, and the rotation of the cylinder drives the ring to rotate synchronously. The permanent magnet group 13 and the filler 14 are disposed outside the rotor iron core 12 , and the permanent magnet group 13 is disposed outside the rotor iron core 12 in a circular array whose center is located on the axis 101 . An oblique slot 16 is formed between the filler 14 and the permanent magnet group 13 , and the opening of the inclined slot 16 faces the outside of the rotor structure 100 along the axial direction. The inclined slot 16 can increase the contact area between the permanent magnet group 13 and the air, thereby increasing the permanent magnet group. The heat dissipation area of 13 is beneficial to the heat dissipation of the rotor structure 100 . The composite sheath 15 is sleeved on the outside of the permanent magnet group 13 and the filler 14 , and the arrangement of the composite sheath 15 can prevent the permanent magnets 131 from separating from the rotor structure 100 when the rotor structure 100 rotates at high speed. The composite sheath 15 includes a thermal conductive layer 151 and a sheath ring 152 , the thermal conductive layer 151 wraps the permanent magnet group 13 and the filler 14 , and the thermal conductive layer 151 is used to conduct the heat of the rotor structure 100 , that is, the thermal conductive layer 151 absorbs the heat inside the rotor structure 100 , and heat dissipation is achieved through the heat exchange between the thermal conductive layer 151 and the outside air. The sheath ring 152 is arranged around the outer side of the thermal conductive layer 151 at intervals along the axis 101. The sheath ring 152 can enhance the strength of the composite sheath 15, and the sheath ring The spaced arrangement of the 152 can reduce the influence of the sheath ring 152 on the thermally conductive layer 151 .

1 to 4 , the thermally conductive layer 151 in the composite sheath 15 wraps the permanent magnet group 13 and the filler 14 and is provided, and the sheath ring 152 is arranged along the axis 101 to wrap around the outer side of the thermally conductive layer 151 at intervals. The heat-conducting layer 151 is used for conducting heat, that is, the heat inside the rotor structure 100 is conducted to the heat-conducting layer 151 , and the heat-conducting layer 151 dissipates heat through heat exchange with air. The higher the heat conduction efficiency of the heat conduction layer 151 is, the better the heat dissipation performance of the rotor structure 100 is. The material of the heat-conducting layer 151 is at least one of iron alloy, aluminum alloy or titanium alloy. The above-mentioned materials have high thermal conductivity and can effectively conduct heat, thereby improving the heat dissipation effect of the rotor structure 100 . The sheath ring 152 is used to bind the thermally conductive layer 151 to improve the strength and rigidity of the composite sheath 15, thereby reducing the strength requirement of the thermally conductive layer 151, that is, the thickness of the thermally conductive layer 151 can be reduced, thereby improving the heat dissipation efficiency in disguised form and reducing the composite sheathing. Eddy current loss caused by excessive thickness of sleeve 15. The material of the sheath ring 152 is at least one of carbon fiber, Kevlar or nylon. The above-mentioned materials have the advantages of high temperature resistance, friction resistance, electrical conductivity, thermal conductivity and corrosion resistance. The material is softer but less thermally conductive. When the composite sheath 15 is installed, an interference amount is provided, and the interference amount can resist centrifugal force when the rotor structure 100 rotates at a high speed, thereby protecting the permanent magnet 131 . It can be understood that the interference is basically realized by the sheath ring 152 , and the sheath ring 152 binds the thermally conductive layer 151 , so as to realize the setting of the interference of the composite sheath 15 . Obviously, the composite jacket 15 made of iron alloy and other materials has strong thermal conductivity, strong electrical conductivity, and large thickness, and the strong thermal conductivity can improve the heat dissipation efficiency of the composite jacket 15. The large eddy current loss and large thickness are not conducive to the heat dissipation of the rotor structure 100; the composite sheath 15 made of carbon fiber and other materials has small thickness, high tensile strength, weak conductivity, strong impact resistance, and weak puncture resistance against sharp objects. Weak thermal conductivity and small thickness are conducive to the heat dissipation of the composite sheath 15 and can reduce costs, high tensile strength and strong impact resistance can improve the strength of the composite sheath 15, and weak electrical conductivity can reduce the loss of eddy currents in the composite sheath 15 The strong impact resistance can effectively prevent the composite sheath 15 from sinking, the weak anti-piercing ability of sharp objects is not conducive to the composite sheath 15 wrapping the permanent magnet 131, and the weak thermal conductivity is not conducive to the composite sheath 15 to dissipate heat. To sum up, the composite sheath 15 formed by a combination of materials such as ferroalloy and carbon fiber, that is, the composite sheath 15 in this embodiment, has a thin thermal conductive layer 151 made of ferroalloy and other materials, which can effectively improve the composite sheath. The heat dissipation efficiency of the sleeve 15 is reduced, the manufacturing cost of the composite sheath 15 is reduced, and the loss of eddy currents in the composite sheath 15 is reduced. Disposing the thermal conductive layer 151 to wrap the permanent magnet 131 can reduce the possibility of the permanent magnet 131 piercing the composite sheath 15 . The sheath ring 152 made of carbon fiber and other materials binds the thermally conductive layer 151. The high tensile strength of carbon fiber can effectively realize the interference fit between the composite sheath 15 and the permanent magnet group 13, and the carbon fiber and other materials have strong impact resistance. The concavity of the composite sheath 15 can be effectively avoided, and the sheath rings 152 are arranged at intervals, so as to maximize the contact area between the thermal conductive layer 151 and the air, and effectively prevent the sheath ring 152 from hindering the heat dissipation of the thermal conductive layer 151 .

The composite sheath 15 further includes annular grooves 153 , and the annular grooves 153 are arranged at intervals along the axis 101 on the outside of the thermally conductive layer 151 , and the annular grooves 153 are recessed in the thermally conductive layer 151 . The sheath ring 152 is disposed in the ring groove 153 , which can effectively prevent the sheath ring 152 from detaching from the heat conducting layer 151 . Secondly, the ring groove 153 can increase the contact area between the sheathing ring 152 and the thermally conductive layer 151 . Under the condition that the pressure of the sheathing ring 152 on the thermally conductive layer 151 remains unchanged, the larger the contact area between the sheathing ring 152 and the thermally conductive layer 151 is, the greater the The smaller the pressure on the 151 is, the load on the heat-conducting layer 151 is reduced, and the service life of the heat-conducting layer 151 is prolonged in disguised form, that is, the service life of the rotor structure 100 is prolonged. The cross-sectional shape of the ring groove 153 basically matches that of the sheath ring 152 , that is, the sheath ring 152 can completely fill the ring groove 153 , so that the surface of the thermally conductive layer 151 is smooth and flat.

5 to 6 , the permanent magnet group 13 includes several permanent magnets 131 , that is, the permanent magnet group 13 is composed of several permanent magnets 131 . The permanent magnets 131 in the single permanent magnet group 13 are basically arranged along the direction of the axis 101 and are basically arranged in a stepped shape. It can be understood that a single permanent magnet group 13 consists of several permanent magnets, and the several permanent magnets 131 are basically arranged along the direction of the axis 101 , which can suppress the formation of large eddy currents when the motor is running, thereby reducing eddy current losses. It can be understood that the permanent magnets 131 are fixed to the outside of the rotor core 12 by means of bonding, so as to facilitate the arrangement of several permanent magnets 131 in a single permanent magnet group 13 in a stepped manner. It can be understood that the number of permanent magnets 131 in a single permanent magnet group 13 is at least two, so that the inclined slot 16 is formed between the permanent magnet group 13 and the filler 14 . The permanent magnet 131 is located between the rotor iron core 12 and the heat-conducting layer 151 . In order to improve space utilization, the permanent magnet 131 is attached to the rotor iron core 12 , that is, the permanent magnet 131 has at least one side surface corresponding to the outer curved surface of the rotor iron core 12 . That is, at least one side surface of the permanent magnet 131 is an arc surface, and the center of the arc surface is located on the axis 101 . The heat-conducting layer 151 is arranged around the permanent magnet group 13. The composite sheath 15 in the conventional rotor structure 100 is a ring body. In this embodiment, the heat-conducting layer 151 is also arranged as a ring body. Other shapes can improve the space utilization rate, reduce the possibility of deformation of the composite sheath 15 , and facilitate the setting of the interference of the composite sheath 15 . In order to match the ring shape of the thermally conductive layer 151 and improve the space utilization rate, the permanent magnet 131 has at least one side surface corresponding to the inner curved surface of the thermally conductive layer 151, that is, at least one side surface of the permanent magnet 131 is an arc surface, and the center of the arc surface is located on the axis. 101 on. To sum up, the permanent magnet 131 is matched with the outer curved surface of the rotor core 12 and the inner curved surface of the heat conducting layer 151 . The permanent magnet 131 has at least two arc surfaces, and the centers of the two arc surfaces are located on the axis 101 . In this embodiment, the permanent magnet 131 is set in the shape of a fan ring body, and the fan ring body is provided with at least two side surfaces which are arc surfaces, and the centers of the two arc surfaces are the same. In addition, the sector ring bodies are also favorable for a stepped arrangement, thereby simplifying the arrangement of the permanent magnets 131 .

2 , 5 and 6 , the filler 14 is located between the rotor core 12 and the thermally conductive layer 151 , and the filler 14 is used to support the composite sheath 15 to prevent the composite sheath 15 from being dented. The filler 14 can be set as a sector ring body, so that one of the cambered surfaces of the filler 14 fits with the outer curved surface of the rotor core 12, and the other cambered surface of the filler 14 fits with the inner curved surface of the thermally conductive layer 151, so as to improve the performance. The support of the filler 14 to the thermally conductive layer 151 prevents the thermally conductive layer 151 from denting, that is, the composite sheath 15 from denting. It can be understood that the material of the filler 14 can be epoxy resin. The epoxy resin has high strength, good electrical insulation performance, can be bonded with various materials, and is flexible in its use process. In addition, an inclined slot 16 is formed between the filler 14 and the permanent magnet group 13 , and the inclined slot 16 is used to increase the contact area between the permanent magnet group 13 and the air, thereby facilitating the heat dissipation of the permanent magnet group 13 .

The filler 14 is attached to the permanent magnet group 13 , and the attachment method is as follows: among the permanent magnets 131 arranged in the direction of the axis 101 in the permanent magnet group 13 , the permanent magnets 131 at the head and tail are attached to the filler 14 , and the permanent magnets at the head are attached to the filler 14 . 131 is attached to the side of one filler 14 , and the tail permanent magnet 131 is attached to the side of the other filler 14 . The remaining permanent magnets 131 are separated from the filler 14 to form two inclined grooves 16 , and the openings of the two inclined grooves 16 are along the axial direction, and the directions are opposite. This bonding method enables the composite sheath 15 to be supported by the filler 14 and the permanent magnet group 13 in the circumferential direction, so as to prevent the composite sheath 15 from being depressed under pressure, that is, to enhance the strength and rigidity of the composite sheath 15 . It can be understood that the number of the inclined slots 16 is twice the number of the permanent magnet groups 13 , and the number of the fillers 14 is the same as the number of the permanent magnet groups 13 . It can be understood that the head and tail permanent magnets 131 in the permanent magnet group 13 are attached to the filler 14, and this attachment method can prevent the edges of the permanent magnets 131 from contacting the composite sheath 15, that is, to prevent the edges of the permanent magnets 131 from piercing the composite sheath. The sleeve 15 is thus protected by the filler 14 to the composite sheath 15, and the service life of the rotor structure 100 is improved in disguised form. The shapes and sizes of the permanent magnets 131 in any one of the permanent magnet groups 13 are exactly the same. The shape and size of the permanent magnets 131 are the same, which can simplify the processing steps of the permanent magnets 131, thereby reducing the manufacturing cost of the rotor structure 100, and making each The permanent magnets 131 have the same performance, which improves the stability of the rotor structure 100 during operation.

A ventilation channel 141 is also provided in the filler 14 , and the ventilation channel 141 is used to improve the heat dissipation effect of the rotor structure 100 . The ventilation channel 141 runs through the filler 14 in the direction of the axis 101. When the wind enters from the end cover of the motor, the air path formed by the wind basically extends along the direction of the axis 101, that is, the air path is substantially parallel to the ventilation channel 141, which is conducive to wind penetration. Through the rotor structure 100 , when the wind passes through the rotor structure 100 , part of the heat in the rotor structure 100 may be taken away by heat exchange. The air passage is substantially parallel to the air passage 141 , which can maximize the heat dissipation effect of the air passage 141 when the rotor structure 100 is stationary.

Embodiment 2:

1 to 4 , a rotor structure 100 of a permanent magnet synchronous motor according to this embodiment includes a rotating shaft 11 , a rotor core 12 , a permanent magnet group 13 , a filler 14 and a composite sheath 15 , and the rotating shaft 11 , the rotor The iron core 12 , the permanent magnet group 13 and the composite sheath 15 are arranged in order from the inside to the outside, and the filler 14 and the permanent magnet group 13 are in the same layer. The rotating shaft 11 rotates around the axis 101 , the rotor core 12 is sleeved on the outside of the rotating shaft 11 , and the rotating shaft 11 drives the rotor core 12 to rotate, that is, the rotor core 12 also rotates around the axis 101 . It can be understood that the shape of the rotating shaft 11 is a cylinder, and the shape of the rotor core 12 is a ring. The ring is sleeved on the outside of the cylinder, and the rotation of the cylinder drives the ring to rotate synchronously. The permanent magnet group 13 and the filler 14 are disposed outside the rotor iron core 12 , and the permanent magnet group 13 is disposed outside the rotor iron core 12 in a circular array whose center is located on the axis 101 . An oblique slot 16 is formed between the filler 14 and the permanent magnet group 13 , and the opening of the inclined slot 16 faces the outside of the rotor structure 100 along the axial direction. The inclined slot 16 can increase the contact area between the permanent magnet group 13 and the air, thereby increasing the permanent magnet group. The heat dissipation area of 13 is beneficial to the heat dissipation of the rotor structure 100 . The composite sheath 15 is sleeved on the outside of the permanent magnet group 13 and the filler 14 , and the arrangement of the composite sheath 15 can prevent the permanent magnets 131 from separating from the rotor structure 100 when the rotor structure 100 rotates at high speed. The composite sheath 15 includes a thermal conductive layer 151 and a sheath ring 152 , the thermal conductive layer 151 wraps the permanent magnet group 13 and the filler 14 , and the thermal conductive layer 151 is used to conduct the heat of the rotor structure 100 , that is, the thermal conductive layer 151 absorbs the heat inside the rotor structure 100 , and heat dissipation is achieved through the heat exchange between the thermal conductive layer 151 and the outside air. The sheath ring 152 is arranged around the outer side of the thermal conductive layer 151 at intervals along the axis 101. The sheath ring 152 can enhance the strength of the composite sheath 15, and the sheath ring The spaced arrangement of the 152 can reduce the influence of the sheath ring 152 on the thermally conductive layer 151 .

1 to 4 , the thermally conductive layer 151 in the composite sheath 15 is arranged around the permanent magnet group 13 and the filler 14 , and the sheath ring 152 is arranged around the outer side of the thermally conductive layer 151 along the axis 101 at intervals. The heat conducting layer 151 is used for conducting heat, that is, the heat inside the rotor structure 100 is conducted to the heat conducting layer 151 , and the heat conducting layer 151 dissipates heat through heat exchange with air. The higher the heat conduction efficiency of the heat conduction layer 151 is, the better the heat dissipation performance of the rotor structure 100 is. The material of the heat-conducting layer 151 is iron alloy, aluminum alloy or titanium alloy, etc. The above-mentioned materials have high thermal conductivity and can effectively conduct heat, thereby improving the heat dissipation effect of the rotor structure 100 . The sheath ring 152 is used to bind the thermally conductive layer 151 to improve the strength and rigidity of the composite sheath 15, thereby reducing the strength requirement of the thermally conductive layer 151, that is, the thickness of the thermally conductive layer 151 can be reduced, thereby improving the heat dissipation efficiency in a disguised form and reducing the composite sheathing. Eddy current loss caused by excessive thickness of sleeve 15. The material of the sheath ring 152 is carbon fiber, Kevlar or nylon, etc., the above-mentioned materials have the advantages of high temperature resistance, friction resistance, electrical conductivity, thermal conductivity and corrosion resistance, and carbon fiber and other materials are compared with iron alloys and other materials. But the thermal conductivity is worse. When the composite sheath 15 is installed, an interference amount is provided, and the interference amount can resist centrifugal force when the rotor structure 100 rotates at a high speed, thereby protecting the permanent magnet 131 . It can be understood that the interference is basically achieved by the sheath ring 152 , and the sheath ring 152 binds the thermally conductive layer 151 , thereby realizing the setting of the interference of the composite sheath 15 . Obviously, the composite jacket 15 made of iron alloy and other materials has strong thermal conductivity, strong electrical conductivity, and large thickness, and the strong thermal conductivity can improve the heat dissipation efficiency of the composite jacket 15. The large eddy current loss and large thickness are not conducive to the heat dissipation of the rotor structure 100; the composite sheath 15 made of carbon fiber and other materials has small thickness, high tensile strength, weak electrical conductivity, strong impact resistance, and weak puncture resistance against sharp objects. Weak thermal conductivity and small thickness are conducive to the heat dissipation of the composite sheath 15 and can reduce costs, high tensile strength and strong impact resistance can improve the strength of the composite sheath 15, and weak electrical conductivity can reduce the loss of eddy currents in the composite sheath 15 The strong impact resistance can effectively prevent the composite sheath 15 from sinking, the weak anti-piercing ability of sharp objects is not conducive to the composite sheath 15 wrapping the permanent magnet 131, and the weak thermal conductivity is not conducive to the composite sheath 15 to dissipate heat. To sum up, the composite sheath 15 formed by a combination of materials such as ferroalloy and carbon fiber, that is, the composite sheath 15 in this embodiment, has a thin thermal conductive layer 151 made of ferroalloy and other materials, which can effectively improve the composite sheath. The heat dissipation efficiency of the sleeve 15 is reduced, the manufacturing cost of the composite sheath 15 is reduced, and the loss of eddy currents in the composite sheath 15 is reduced. Disposing the thermal conductive layer 151 to wrap the permanent magnet 131 can reduce the possibility of the permanent magnet 131 piercing the composite sheath 15 . The sheath ring 152 made of carbon fiber and other materials binds the thermally conductive layer 151. The high tensile strength of carbon fiber can effectively realize the interference fit between the composite sheath 15 and the permanent magnet group 13, and the carbon fiber and other materials have strong impact resistance. The concave of the composite sheath 15 can be effectively avoided, and the sheath rings 152 are arranged at intervals, so as to maximize the contact area between the thermally conductive layer 151 and the air, and effectively prevent the sheathed rings 152 from hindering the heat dissipation of the thermally conductive layer 151 .

The composite sheath 15 further includes annular grooves 153 , and the annular grooves 153 are arranged at intervals along the axis 101 on the outside of the thermally conductive layer 151 , and the annular grooves 153 are recessed in the thermally conductive layer 151 . The sheath ring 152 is disposed in the ring groove 153 , which can effectively prevent the sheath ring 152 from detaching from the heat conducting layer 151 . Secondly, the ring groove 153 can increase the contact area between the sheathing ring 152 and the thermally conductive layer 151 . Under the condition that the pressure of the sheathing ring 152 on the thermally conductive layer 151 remains unchanged, the larger the contact area between the sheathing ring 152 and the thermally conductive layer 151 is, the greater the The smaller the pressure on the 151 is, the load on the heat-conducting layer 151 is reduced, and the service life of the heat-conducting layer 151 is prolonged in disguised form, that is, the service life of the rotor structure 100 is prolonged. The cross-sectional shape of the ring groove 153 basically matches that of the sheath ring 152 , that is, the sheath ring 152 can completely fill the ring groove 153 , so that the surface of the thermally conductive layer 151 is smooth and flat.

7 to 8 , the permanent magnet group 13 includes several permanent magnets 131 , that is, the permanent magnet group 13 is composed of several permanent magnets. The lengths of the permanent magnets 131 in the permanent magnet group 13 are different, and the permanent magnets 131 in the single permanent magnet group 13 are arranged in sequence along the axis direction according to the length of the permanent magnet group 13 , and one of the permanent magnets 131 in the single permanent magnet group 13 Both sides are fitted with the filler 14 , and the permanent magnet 131 with the longest length in a single permanent magnet group 13 is fitted with another filler 14 . It can be understood that a single permanent magnet group 13 consists of several permanent magnets, and the several permanent magnets 131 are basically arranged along the direction of the axis 101 , which can suppress the formation of large eddy currents when the motor is running, thereby reducing eddy current losses. It can be understood that the permanent magnets 131 are fixed to the outside of the rotor core 12 by means of bonding, so as to facilitate the arrangement of several permanent magnets 131 in a single permanent magnet group 13 . It can be understood that the number of permanent magnets 131 in a single permanent magnet group 13 is at least two, so that the inclined slot 16 is formed between the permanent magnet group 13 and the filler 14 . The permanent magnet 131 is located between the rotor iron core 12 and the heat-conducting layer 151 . In order to improve space utilization, the permanent magnet 131 is attached to the rotor iron core 12 , that is, the permanent magnet 131 has at least one side surface corresponding to the outer curved surface of the rotor iron core 12 . That is, at least one side surface of the permanent magnet 131 is an arc surface, and the center of the arc surface is located on the axis 101 . The heat-conducting layer 151 is arranged around the permanent magnet group 13. The composite sheath 15 in the conventional rotor structure 100 is a ring body. In this embodiment, the heat-conducting layer 151 is also arranged as a ring body. Other shapes can improve the space utilization rate, reduce the possibility of deformation of the composite sheath 15 , and facilitate the setting of the interference of the composite sheath 15 . In order to match the ring shape of the thermally conductive layer 151 and improve the space utilization rate, the permanent magnet 131 has at least one side surface corresponding to the inner curved surface of the thermally conductive layer 151, that is, at least one side surface of the permanent magnet 131 is an arc surface, and the center of the arc surface is located on the axis. 101 on. To sum up, the permanent magnet 131 is matched with the outer curved surface of the rotor core 12 and the inner curved surface of the heat conducting layer 151 . The permanent magnet 131 has at least two arc surfaces, and the centers of the two arc surfaces are located on the axis 101 . In this embodiment, the permanent magnet 131 is set in the shape of a fan ring body, and the fan ring body is provided with at least two side surfaces which are arc surfaces, and the centers of the two arc surfaces are the same. In addition, the sector ring bodies are also favorable for a stepped arrangement, thereby simplifying the arrangement of the permanent magnets 131 .

Referring to FIGS. 2 , 7 and 8 , the filler 14 is located between the rotor core 12 and the heat conducting layer 151 , and the filler 14 is used to improve the rigidity of the rotor structure 100 and prevent the composite sheath 15 from denting. The filler 14 can be set as a sector ring body, so that one of the cambered surfaces of the filler 14 fits with the outer curved surface of the rotor core 12, and the other cambered surface of the filler 14 fits with the inner curved surface of the thermally conductive layer 151, so as to improve the performance. The support of the filler 14 to the thermally conductive layer 151 prevents the thermally conductive layer 151 from denting, that is, the composite sheath 15 from denting. It can be understood that the material of the filler 14 can be epoxy resin. The epoxy resin has high strength, good electrical insulation performance, can be bonded with various materials, and is flexible in its use process. In addition, an inclined slot 16 is formed between the filler 14 and the permanent magnet group 13 , and the inclined slot 16 is used to increase the contact area between the permanent magnet group 13 and the air, thereby facilitating the heat dissipation of the permanent magnet group 13 .

The permanent magnets 131 in the single permanent magnet group 13 are different in shape and size, and the permanent magnets 131 in the permanent magnet group 13 are all attached to one of the side surfaces of the filler 14, and the permanent magnets 131 are arranged in a stepped shape, that is, the permanent magnet group. One of the permanent magnets 131 at the head or tail of the 13 is attached to the filler 14, and the other permanent magnets 131 are not attached to the side of the filler 14, thereby forming an inclined slot 16, which can increase the number of pairs of the permanent magnet group 13. The supporting area of the sheath 15 increases the strength and rigidity of the composite sheath 15, and the wind direction in the motor is generally a single direction, and a unidirectional chute 16 is formed between the permanent magnet group 13 and the filler 14 with an opening along the axis direction. , and the opening of the inclined slot 16 corresponds to the end of the motor into which the wind is passed, thereby improving the heat dissipation efficiency.

A ventilation channel 141 is also provided in the filler 14 , and the ventilation channel 141 is used to improve the heat dissipation effect of the rotor structure 100 . The ventilation channel 141 runs through the filler 14 in the direction of the axis 101. When the wind enters from the end cover of the motor, the air path formed by the wind basically extends along the direction of the axis 101, that is, the air path is substantially parallel to the ventilation channel 141, which is conducive to wind penetration. Through the rotor structure 100 , when the wind passes through the rotor structure 100 , part of the heat in the rotor structure 100 may be taken away by heat exchange. The air passage is substantially parallel to the air passage 141 , which can maximize the heat dissipation effect of the air passage 141 when the rotor structure 100 is stationary.

In the prior art, the rotor structure in the permanent magnet synchronous motor is difficult to dissipate heat, the contact area between the permanent magnet and the air in the rotor structure is limited, the contact area between the permanent magnet and the air is mainly the two end faces of the permanent magnet, and the The composite sheath structure has the problem that the composite sheath is too thick, which is not conducive to the heat dissipation of the rotor structure, and the composite sheath in the existing rotor structure uses a single material, which has limitations. In the rotor structure 100 of the present invention, by arranging the permanent magnets 131 in a stepped arrangement, the contact area between the permanent magnets 131 and the air is increased, that is, the heat dissipation area of the permanent magnets 131 is increased. Various materials are used, which can improve the heat dissipation efficiency and produce many beneficial effects.

Only the preferred embodiments of the present invention have been described in detail above, but the present invention is not limited to the above-mentioned embodiments, and within the scope of knowledge possessed by those of ordinary skill in the art, various aspects can also be made without departing from the purpose of the present invention. Various changes should be included within the protection scope of the present invention.

Claims (10)

1. A rotor structure of a permanent magnet synchronous motor, comprising:

a shaft that rotates about an axis;

the rotor iron core is sleeved outside the rotating shaft;

the permanent magnet group is arranged on the outer side of the rotor iron core;

a composite sheath sleeved outside the permanent magnet group, the composite sheath comprising:

the heat conduction layer is arranged to wrap the permanent magnet group and is used for conducting heat;

the sheath rings are wound on the outer side of the heat conduction layer at intervals along the axis direction and are used for improving the strength of the composite sheath;

the filler, the filler set up in rotor core with between the compound sheath, the filler with at least partial laminating of permanent magnet group, and the laminating department closes on the axial both ends of compound sheath, just the filler with be formed with the chute between the permanent magnet group, chute opening direction is parallel with the axis direction basically, the chute is used for the increase the area of contact of permanent magnet group and air.

2. The rotor structure of a permanent magnet synchronous motor according to claim 1, wherein the permanent magnet group comprises permanent magnets, the permanent magnets are in the shape of a sector ring body, and the center of the sector ring body is located on the axis.

3. The rotor structure of a permanent magnet synchronous motor according to claim 2, wherein there are at least two permanent magnets, and the permanent magnets in the permanent magnet group are arranged substantially in the axial direction.

4. The rotor structure of a PMSM according to claim 3, wherein each of the permanent magnets in the permanent magnet groups are identical, and the permanent magnets in a single permanent magnet group are arranged in a stepped shape, two chutes are formed between a single permanent magnet group and the filler, and the opening directions of the two chutes are opposite.

5. The rotor structure of a permanent magnet synchronous motor according to claim 3, wherein the permanent magnets in the permanent magnet groups are different in length, the permanent magnets in a single permanent magnet group are sequentially arranged in an axial direction in an increasing or decreasing length manner, one side of each permanent magnet in the single permanent magnet group is attached to the filler, and the permanent magnet with the longest length in the single permanent magnet group is attached to the other filler.

6. The rotor structure of a permanent magnet synchronous motor according to claim 1, wherein the filler is shaped as a sector ring, the center of the sector ring is located on the axis, and the filler is disposed around the axis.

7. The rotor structure of a permanent magnet synchronous motor according to claim 1, wherein the filler includes:

an air duct penetrating the filler in the axis direction.

8. The rotor structure of a permanent magnet synchronous motor according to claim 1, wherein the composite sheath further comprises:

the annular grooves are arranged on the outer side of the heat conducting layer at intervals along the axis direction, and the sheath ring is sleeved in the annular grooves.

9. The rotor structure of a permanent magnet synchronous motor according to claim 1, wherein the material of the heat conducting layer is at least one of an iron alloy, an aluminum alloy or a titanium alloy.

10. The rotor structure of a permanent magnet synchronous motor according to claim 1, wherein the material of the sheath ring is at least one of carbon fiber, Kevlar or nylon.

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