CN113437825B

CN113437825B - Motor heat radiation structure, motor and compressor

Info

Publication number: CN113437825B
Application number: CN202110758163.6A
Authority: CN
Inventors: 沈静文; 赖涛; 卢素华; 黄恒
Original assignee: Gree Electric Appliances Inc of Zhuhai
Current assignee: Gree Electric Appliances Inc of Zhuhai; Zhuhai Kaibang Motor Manufacture Co Ltd
Priority date: 2021-07-05
Filing date: 2021-07-05
Publication date: 2022-06-28
Anticipated expiration: 2041-07-05
Also published as: CN113437825A

Abstract

The invention provides a motor heat dissipation structure, a motor and a compressor, wherein the motor heat dissipation structure comprises a stator iron core and a stator winding wound on a tooth part of the stator iron core, the stator winding is provided with a first winding end part protruding out of one axial end of the stator iron core, the first winding end part is provided with a heat dissipation part, a first cooling flow channel is arranged in the heat dissipation part, and the heat dissipation part is wrapped and attached to the first winding end part in a potting mode. According to the invention, the heat dissipation part can be tightly attached to the first winding end part, so that the heat of the first winding end part can be cooled and dissipated more efficiently through the heat dissipation part, the cooling effect is better, meanwhile, the heat dissipation part does not need to be separately assembled and fixed, and the internal structure of the motor is simplified.

Description

Motor heat radiation structure, motor and compressor

Technical Field

The invention belongs to the technical field of motor manufacturing, and particularly relates to a motor heat dissipation structure, a motor and a compressor.

Background

With the continuous optimization of rare earth material process and the gradual emphasis of energy conservation and environmental protection by the state, the screw compressor motor is gradually switched into a variable-frequency permanent magnet synchronous motor, the advantages of high power density, small motor volume, high energy efficiency and the like are widely applied, but the cost is higher compared with a fixed-frequency motor. In order to further improve the competitiveness of the motor, the power density needs to be further improved, and the most important reason for restricting the motor at present is that the heat load is higher due to high power density, and the motor efficiency is lower and the reliability is poor due to the temperature rise of the motor in practical application. Therefore, the improvement of the heat dissipation capability of the motor is a key step of future development.

At present, the common heat dissipation mode of a high-power motor is a water cooling mode and an oil cooling mode, a flow channel is generally designed in a shell, heat generated by a stator winding passes through an iron core and the shell and then is carried away through water in the flow channel, the cooling effect is not good enough, the heat load of the motor cannot be further improved, the power density and the cost are reduced, and the product competitiveness of the motor is improved.

In order to overcome the foregoing disadvantages, a method of implementing the specific cooling heat dissipation of the winding end portion by using a cooling pipeline provided for the end portion of the motor stator winding is also provided in the prior art, and a manner of laying a corresponding cooling pipe on the outer circumferential surface of the winding is specifically adopted.

Disclosure of Invention

Therefore, the invention provides a motor heat dissipation structure, a motor and a compressor, which can overcome the defects of poor cooling effect and difficulty in assembly and fixation of the stator winding end part in a cooling pipe cooling mode in the related art.

In order to solve the above problems, the present invention provides a heat dissipation structure for a motor, including a stator core and a stator winding wound around a tooth portion of the stator core, where the stator winding has a first winding end portion protruding out of one axial end of the stator core, the first winding end portion has a heat dissipation portion, the heat dissipation portion has a first cooling flow channel therein, and the heat dissipation portion is wrapped around the first winding end portion in an encapsulating manner.

Preferably, the heat dissipation part is made of a high-damping heat conduction material; and/or the first cooling flow channel is spiral-shaped and extends around the axis of the stator core.

Preferably, the high-damping heat-conducting material comprises at least one of epoxy resin glue and high-performance polyurethane glue.

Preferably, the heat dissipation structure of the motor further comprises a housing, wherein a second cooling flow passage is arranged in the housing, and the second cooling flow passage is communicated with the first cooling flow passage.

Preferably, in the axial cross section of the casing, the cross section of the second cooling flow channel is rectangular, the rectangle has a width L1 in the radial direction of the casing and a length L2 in the axial direction of the casing, the thickness of the casing is L, L1 is equal to or less than 50% L, and 1.1L1 is equal to or less than L2 is equal to or less than 2L 1.

Preferably, the cross section of the first cooling flow passage is circular, the first cooling flow passage is provided with a first inlet, the diameter of the first inlet is d1, and d1 is more than or equal to 0.8L2 and is more than or equal to 0.4L 2.

Preferably, the first cooling flow passage further has a first outlet having a diameter equal to a diameter of the first inlet; and/or the circular diameters of the first cooling flow channels in the extension direction thereof are equal.

Preferably, the first inlet and the first outlet are respectively communicated with the second cooling flow channel.

Preferably, the stator winding further has a second winding end portion protruding out of the other axial end of the stator core, the second winding end portion also has the heat dissipation portion, and the heat dissipation portion is wrapped and attached to the second winding end portion in a potting manner.

Preferably, the stator core is provided with a third cooling flow channel running through two axial ends of the stator core, one end of the third cooling flow channel is communicated with the first cooling flow channel in the heat dissipation part wrapped on the first winding end part, and the other end of the third cooling flow channel is communicated with the first cooling flow channel in the heat dissipation part wrapped on the second winding end part; and/or the height of the second winding end part in the axial direction of the stator core is equal to the height of the first winding end part in the axial direction of the stator core.

Preferably, the third cooling flow channel has a plurality of third cooling flow channels extending in the axial direction of the stator core, and the plurality of third cooling flow channels are arranged at even intervals in the circumferential direction of the stator core.

Preferably, the plurality of third cooling flow channels are at a yoke portion of the stator core.

Preferably, the teeth of the stator core are symmetrical with respect to a radial line of the stator core, and the third cooling flow channel is circular, and a center of the circle is located on the radial line, projected on any radial surface of the stator core.

Preferably, the diameter of the circle is d2, the radial thickness of the yoke is L5, and 0.125L5 ≦ d2 ≦ 0.6L 5.

Preferably, L5/6. ltoreq. d 2. ltoreq.L 5/5.

Preferably, the heat dissipation portion has a thickness L3 in the axial direction of the stator core, and the first winding end portion has a thickness L4 in the axial direction of the stator core, where L3 > L4.

Preferably, 1.1L4 ≦ L3 ≦ 1.4L 4.

Preferably, the heat dissipation part is annular, the diameter of the outer circle of the heat dissipation part is equal to that of the outer circle of the stator core, and the diameter of the inner circle of the heat dissipation part is larger than that of the inner circle of the stator core.

The invention provides a motor, which comprises the motor heat dissipation structure.

The invention provides a compressor, which comprises the motor.

According to the motor heat dissipation structure, the motor and the compressor, the heat dissipation part is wrapped on the first winding end part in an encapsulating manner, and can be tightly attached to the first winding end part, so that the heat of the first winding end part can be cooled and dissipated more efficiently through the heat dissipation part, the cooling effect is better, meanwhile, the heat dissipation part does not need to be assembled and fixed independently, and the internal structure of the motor is simplified.

Drawings

Fig. 1 is a schematic structural view (cross section of a motor shaft) of a heat dissipation structure of a motor according to an embodiment of the present invention;

fig. 2 is a schematic structural view (sectional view) of the heat dissipation portion in fig. 1;

fig. 3 is a schematic perspective view of the housing of fig. 1;

FIG. 4 is a schematic view (partially in axial section) of the internal structure of the housing of FIG. 3;

fig. 5 is a schematic perspective view of the stator core shown in fig. 1;

FIG. 6 is a graph relating d2/L5 to stator yoke flux density (d 2/L5 on the abscissa and yoke flux density in T on the ordinate);

FIG. 7 is a graph relating d2/L5 to motor efficiency (d 2/L5 on the abscissa and motor efficiency on the ordinate);

FIG. 8 is a graph relating d2/L5 to motor temperature rise (d 2/L5 on the abscissa and motor temperature rise in K on the ordinate).

The reference numerals are represented as:

1. a stator core; 11. a third cooling flow channel; 2. a stator winding; 3. a heat dissipating section; 31. a first cooling flow passage; 311. a first inlet; 312. a first outlet; 4. a housing; 41. a second cooling flow channel; 42. a housing inlet; 43. a housing outlet; 100. a rotor assembly; 101. an end cap; 102. and a bearing.

Detailed Description

Referring to fig. 1 to 8 in combination, according to an embodiment of the present invention, a heat dissipation structure for a motor is provided, including a stator core 1 and a stator winding 2 wound around a tooth of the stator core 1, where the stator winding 2 has a first winding end portion protruding from an axial end of the stator core 1, the first winding end portion has a heat dissipation portion 3, the heat dissipation portion 3 has a first cooling flow channel 31 therein, and the heat dissipation portion 3 is wrapped around the first winding end portion in an embedding manner, and it can be understood that the heat dissipation portion 3 is made of a heat conductive material. In the technical scheme, the heat dissipation part 3 is wrapped on the first winding end part in a potting manner, and can be tightly attached to the first winding end part, so that the heat of the first winding end part can be cooled and dissipated more efficiently through the heat dissipation part 3, the cooling effect is better, meanwhile, the heat dissipation part 3 does not need to be separately assembled and fixed, and the internal structure of the motor is simplified. A suitable cooling medium such as cooling water, coolant, cooling oil, or the like can be introduced into the first cooling flow channel 31 to timely take away the heat transferred from the end of the first winding.

In some embodiments, the heat dissipating portion 3 is made of a high-damping heat conducting material, for example, at least one of epoxy resin glue and high-performance polyurethane glue, so that the first winding end portion can form a vibration damping support while heat is quickly and efficiently conducted, and vibration noise of the motor is improved.

The first cooling flow channel 31 is a spiral shape extending around the axis of the stator core 1, and the spiral cooling flow channel structure can surround multiple groups of the first winding end part, so that the heat dissipation area of the first winding end part can be increased, and the heat dissipation effect is further improved.

In some embodiments, the heat dissipation structure of the motor further includes a housing 4, the housing 4 has a second cooling flow channel 41, the second cooling flow channel 41 is communicated with the first cooling flow channel 31, and in particular, the first cooling flow channel 31 is respectively communicated with the second cooling flow channel 41 through a first inlet 311 and a first outlet 312 thereof, so that the first cooling flow channel 31 and the second cooling flow channel 41 form a parallel pipeline structure, in this case, on the outer side of the motor, a pipeline connection with an external cooling medium supply device (for example, a water tower device) can be achieved only through a housing inlet 42 and a housing outlet 43, that is, the two cooling flow channels share one inlet and one outlet, thereby simplifying the corresponding pipeline structure.

In some embodiments, the cross-sectional shape of the second cooling flow channel 41 in the axial cross-section of the casing 4 may be a circular shape or another polygonal closed figure, preferably, the cross-section of the second cooling flow channel 41 is a rectangle, which can have a large heat dissipation area, the rectangle has a width L1 in the radial direction of the casing 4 and a length L2 in the axial direction of the casing 4, the thickness of the casing 4 is L, and in order to ensure the mechanical strength of the casing 4, L1 ≦ 50% L, 1.1L1 ≦ L2 ≦ 2L 1. Preferably, the second cooling flow channel 41 is also preferably in a spiral shape extending around the axis of the stator core 1, and in a specific embodiment, the number of spiral turns of the spiral second cooling flow channel 41 is preferably 8 to 10. The rectangular shape has a rounded structure at four corners to reduce flow resistance of the cooling medium.

The cross section of the first cooling flow channel 31 is preferably circular, the first cooling flow channel 31 has a first inlet 311, the diameter of the first inlet 311 is d1, and the diameter of the first inlet 311 is d1 or more and 0.4L2 or more and d1 or more and 0.8L2, in this technical solution, the flow area of the first inlet 311 is smaller than the flow area of the second cooling flow channel 41, the flow rates of the cooling medium in the first cooling flow channel 31 and the second cooling flow channel 41 can be reasonably distributed, and the cooling medium can be ensured to sufficiently cool the corresponding flow-through region in both flow channels, this structural feature is particularly suitable for a horizontally mounted motor structure (as shown in fig. 1), in which the opening of the first inlet 311 is vertically upward, and the foregoing limitation can prevent the cooling medium from entering the first cooling flow channel 31 through the first inlet 311 under the action of gravity when entering the cooling flow channel to cause serious shortage of the cooling medium in the second cooling flow channel 41, The cooling effect on the cabinet 4 becomes poor.

The first cooling flow channel 31 preferably has a first outlet 312 with a diameter equal to the diameter of the first inlet 311, and in a more preferred embodiment, the first cooling flow channel 31 has a circular diameter in the extending direction thereof equal, that is, the first cooling flow channel 31 is a constant diameter channel.

In some embodiments, the stator winding 2 further has a second winding end portion protruding out of the other axial end of the stator core 1, the second winding end portion also has the heat dissipation portion 3, and the heat dissipation portion 3 is attached to the second winding end portion in a potting manner, so that the second winding end portion can be efficiently cooled and dissipated. Preferably, the height of the second winding end portion in the axial direction of the stator core 1 is equal to the height of the first winding end portion in the axial direction of the stator core 1.

In some embodiments, the stator core 1 is configured with third cooling channels 11 penetrating through both ends in the axial direction thereof, one end of the third cooling channel 11 is communicated with the first cooling channel 31 in the heat dissipating portion 3 wrapped on the first winding end portion, and the other end of the third cooling channel 11 is communicated with the first cooling channel 31 in the heat dissipating portion 3 wrapped on the second winding end portion, in this technical solution, the first cooling channel 31 and the third cooling channel 11 are formed by communicating the first cooling channel 31 respectively provided at both ends of the stator core 1 through the third cooling channel 11, so as to form one cooling channel, which can cool the end portion of the stator winding and the stator core 1, and the second cooling channel 41 is another cooling channel arranged in parallel to cool the housing 4, and the two cooling channels share one housing inlet 42, The housing outlet 43 further simplifies the construction.

In some embodiments, the third cooling flow channels 11 have a plurality of third cooling flow channels 11, the plurality of third cooling flow channels 11 extend along the axial direction of the stator core 1, and the plurality of third cooling flow channels 11 are uniformly spaced along the circumferential direction of the stator core 1, and preferably, the plurality of third cooling flow channels 11 are located at a yoke portion of the stator core 1. Further, the teeth of the stator core 1 are symmetrical with respect to a radial line of the stator core 1 by projection on any radial surface of the stator core 1, the third cooling flow channel 11 is circular, and the center of the circle is located on the radial line, that is, it is ensured that the third cooling flow channel 11 is arranged to face the teeth and not to face the stator slots, so that a large adverse effect on the magnetic density of the yoke due to the hole formed in the yoke can be reduced, and meanwhile, the technical scheme also ensures that the number of the third cooling flow channels 11 is matched with the number of the teeth of the stator core 1 (for example, the number of the third cooling flow channels 11 is N, and the value of N should be divisible by Ns (number of stator slots)). In order to further optimize the setting size of the third cooling flow channel 11, so as to be able to take into account higher motor efficiency value, lower temperature rise and magnetic flux density influence, the applicant has conducted necessary research on the correlation between d2/L5 (the diameter of the circle is d2, and the radial thickness of the yoke is L5) and the correlation between the three, when 6 third cooling flow channels 11 are selected, d2 is in the range from 0.125L5 to 0.6L5 (that is, 0.125L5 is not less than d2 and not more than 0.6L5), the results of comparative analysis on the magnetic flux density of the stator yoke of the motor, the motor efficiency and the temperature rise are shown in fig. 6 to 8, it can be obtained that when the value of d2 is greater than 0.4L5, the magnetic flux density of the stator yoke is increased sharply, the efficiency is reduced by about 0.5%, and the effect of the d2 is increased continuously for reducing the motor temperature rise is not obvious, and based on better economic consideration, L5/6 is preferably not less than d2 and not less than L5/5.

In some embodiments, the thickness of the heat dissipation portion 3 in the axial direction of the stator core 1 is L3, the thickness of the first winding end portion in the axial direction of the stator core 1 is L4, and L3 is greater than L4, so as to ensure that the heat dissipation portion 3 completely wraps the first winding end portion, and it can be understood that the thickness of the second winding end portion in the axial direction is also regular with the heat dissipation portion 3 wrapped correspondingly. Furthermore, 1.1L4 is not less than L3 is not less than 1.4L4, so that the manufacturing cost is reduced and the economical efficiency is improved while sufficient structural strength and reliability are ensured after the corresponding heat dissipation flow channel is formed by encapsulation.

In some embodiments, the heat dissipation portion 3 is annular, the diameter of the outer circle of the heat dissipation portion 3 is equal to the diameter (D) of the outer circle of the stator core 1, so that the heat dissipation portion 3 can be ensured to be in close contact with the cavity wall of the housing case 4, the connection reliability is improved, and the diameter of the inner circle of the heat dissipation portion 3 is greater than that of the inner circle of the stator core 1, so that the rotor assembly 100 is prevented from being damaged by collision with the heat dissipation portion 3 during assembly.

According to an embodiment of the present invention, there is provided a motor including the above-mentioned motor heat dissipation structure, a rotor assembly 100 is assembled in an inner hole of the stator core 1 in a penetrating manner, and two ends of a rotating shaft of the rotor assembly 100 are respectively mounted on two end covers 101 of the motor through corresponding bearings 102.

According to an embodiment of the invention, a compressor, in particular a screw compressor, is provided, comprising an electric motor as described above.

It is readily understood by a person skilled in the art that the advantageous ways described above can be freely combined, superimposed without conflict.

The present invention is not limited to the above preferred embodiments, and any modifications, equivalent substitutions and improvements made within the spirit and principle of the present invention should be included in the protection scope of the present invention. The above is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, several improvements and modifications can be made without departing from the technical principle of the present invention, and these improvements and modifications should also be regarded as the protection scope of the present invention.

Claims

1. A motor heat dissipation structure comprises a stator core (1) and a stator winding (2) wound on a tooth part of the stator core (1), wherein the stator winding (2) is provided with a first winding end part protruding out of one axial end of the stator core (1), the motor heat dissipation structure is characterized in that a heat dissipation part (3) is arranged on the first winding end part, a first cooling flow channel (31) is arranged in the heat dissipation part (3), and the heat dissipation part (3) is wrapped on the first winding end part in an encapsulation mode; the cooling device further comprises a machine shell (4), a second cooling flow channel (41) is arranged in the machine shell (4), the second cooling flow channel (41) is communicated with the first cooling flow channel (31), the section of the second cooling flow channel (41) is rectangular on the axial section of the machine shell (4), the rectangle has a length L2 in the axial direction of the machine shell (4), the section of the first cooling flow channel (31) is circular, the first cooling flow channel (31) is provided with a first inlet (311), the diameter of the first inlet (311) is d1, and 0.4L 2 is not less than d1 is not less than 0.8L 2; the rectangle has a width L1 in the radial direction of the machine shell (4), the thickness of the machine shell (4) is L, L1 is equal to or less than 50% L, and L2 is equal to or less than 1.1L1 and is equal to or less than 2L 1.

2. The heat dissipation structure of an electric motor according to claim 1, wherein the heat dissipation part (3) is made of a high-damping heat conductive material.

3. The electric machine heat dissipation structure of claim 2, wherein the high-damping heat conductive material comprises at least one of an epoxy glue, a high-performance polyurethane glue.

4. The motor heat dissipation structure according to claim 1, wherein the first cooling flow channel (31) is a spiral shape extending around an axis of the stator core (1).

5. The motor heat dissipation structure according to claim 1, wherein the first cooling flow channel (31) further has a first outlet (312), and a diameter of the first outlet (312) is equal to a diameter of the first inlet (311); and/or the circular diameters of the first cooling channels (31) in the direction of their extent are equal.

6. The heat dissipation structure of an electric motor according to claim 5, wherein the first inlet (311) and the first outlet (312) are respectively communicated with the second cooling flow channel (41).

7. The motor heat dissipation structure according to any one of claims 1 to 6, wherein the stator winding (2) further has a second winding end portion protruding from the other axial end of the stator core (1), and the heat dissipation portion (3) is also provided on the second winding end portion, and the heat dissipation portion (3) is encapsulated on the second winding end portion.

8. The heat dissipation structure of an electric motor according to claim 7, wherein the stator core (1) is configured with third cooling flow channels (11) penetrating through both axial ends thereof, one end of each third cooling flow channel (11) is communicated with the first cooling flow channel (31) in the heat dissipation part (3) wrapped on the first winding end, and the other end of each third cooling flow channel (11) is communicated with the first cooling flow channel (31) in the heat dissipation part (3) wrapped on the second winding end; and/or the height of the second winding end part in the axial direction of the stator core (1) is equal to the height of the first winding end part in the axial direction of the stator core (1).

9. The heat dissipation structure for an electric machine according to claim 8, wherein the third cooling flow channel (11) has a plurality of third cooling flow channels, the plurality of third cooling flow channels (11) extends in an axial direction of the stator core (1), and the plurality of third cooling flow channels (11) are uniformly spaced in a circumferential direction of the stator core (1).

10. The motor heat dissipation structure according to claim 9, wherein the plurality of third cooling flow channels (11) are located at a yoke portion of the stator core (1).

11. The heat dissipation structure of an electric machine according to claim 10, wherein the teeth of the stator core (1) are symmetric with respect to a radial line of the stator core (1) in projection on any radial surface of the stator core (1), and the third cooling flow channels (11) are circular, and the center of the circle is located on the radial line.

12. The heat dissipation structure of an electric motor according to claim 11, wherein the diameter of the circle is d2, the radial thickness of the yoke is L5, 0.125L5 ≤ d2 ≤ 0.6L 5.

13. The heat dissipation structure of the motor as claimed in claim 12, wherein L5/6/d 2/L5/5.

14. The motor heat dissipation structure according to any one of claims 1 to 6, wherein the heat dissipation part (3) has a thickness of L3 in the axial direction of the stator core (1), and the first winding end part has a thickness of L4 in the axial direction of the stator core (1), and L3 > L4.

15. The heat dissipation structure of the motor as claimed in claim 14, wherein 1.1L 4/L3/1.4L 4.

16. The heat dissipation structure of the motor according to claim 1, wherein the heat dissipation part (3) is annular, the diameter of the outer circle of the heat dissipation part (3) is equal to the diameter of the outer circle of the stator core (1), and the diameter of the inner circle of the heat dissipation part (3) is larger than the diameter of the inner circle of the stator core (1).

17. An electric motor characterized by comprising the motor heat dissipation structure of any one of claims 1 to 16.

18. A compressor comprising the motor of claim 17.