CN118971449A

CN118971449A - Motor with cooling structure

Info

Publication number: CN118971449A
Application number: CN202310542658.4A
Authority: CN
Inventors: 许楠楠; 黄建成; 陈达
Original assignee: Schaeffler Technologies AG and Co KG
Current assignee: Schaeffler Technologies AG and Co KG
Priority date: 2023-05-15
Filing date: 2023-05-15
Publication date: 2024-11-15

Abstract

The application proposes an electric machine with a cooling structure, comprising: a housing (1); a rotor (3) rotatably connected to the housing (1) with respect to the housing (1); and stator (2), stator (2) cover is located the radial outside of rotor (3), stator (2) include stator core (21) and stator winding (22), stator winding (22) install in stator core (21), stator winding (22) are provided with hollow fluid passageway (23), fluid passageway (23) make both ends intercommunication on axial (A) of stator (2), fluid can pass through fluid passageway (23) by axial one end of stator (2) flows the axial other end.

Description

Motor with cooling structure

Technical Field

The application belongs to the technical field of motors, and particularly relates to a motor with a cooling structure.

Background

The cooling of the stator windings by the drive motor of an electric vehicle may include several methods:

1. Cooling by oil at the winding ends.

2. An oil groove is arranged around the winding, and the surface of the winding is cooled by oil.

3. An oil groove is arranged on the outer peripheral surface of the stator, and the surface of the stator is cooled by oil.

4. The oil cools through the gaps of the windings.

However, the above cooling method can cool only a partial region of the winding or indirectly cool the winding, so that the cooling efficiency is low and the cooling effect is poor.

Disclosure of Invention

The application aims to provide a motor with a cooling structure, so that the motor has a better cooling effect.

An embodiment of the present application proposes a motor having a cooling structure, including:

A housing;

a rotor rotatably connected to the housing with respect to the housing; and

The stator, the stator cover is located the radial outside of rotor, the stator includes stator core and stator winding, stator winding install in stator core, stator winding is provided with hollow fluid passageway, the fluid passageway makes the axial both ends intercommunication of stator, the fluid can pass through the fluid passageway by the axial one end of stator flows the axial other end.

In at least one possible embodiment, the stator winding comprises a plurality of wires, one or several of the wires having a cross-section in the shape of a semi-enclosure with an opening,

The openings of at least two wires oppositely enclose the oil liquid channel; and/or at least one of the wires and adjacent wires, the stator core or an insulating member within the stator core enclose the oil channel.

In at least one possible embodiment, the stator core has a plurality of stator core slots formed in an inner peripheral portion thereof, the plurality of stator core slots being arranged uniformly in a circumferential direction of the stator, and the stator windings being arranged in the stator core slots.

In at least one possible embodiment, there are a plurality of the oil passages in each of the stator core slots, the plurality of the oil passages being arranged in a radial direction of the stator.

In at least one possible embodiment, the stator winding is wrapped with insulating paper.

In at least one possible embodiment, the housing is provided with an oil inlet and an oil drain, which are located at both ends of the stator in the axial direction.

In at least one possible embodiment, the end regions of the stator winding are formed with sealing spaces, two sealing spaces are respectively communicated with the oil inlet and the oil outlet, and the oil liquid channels are communicated with the sealing spaces at two axial ends of the stator winding.

In at least one possible embodiment, the sealing space is located radially outside the rotor in the radial direction of the electric machine.

In at least one possible embodiment, the cross section of the stator winding comprises a hollow rectangle.

In at least one possible embodiment, sealing sleeves are arranged at the two axial ends of the stator and on the radial inner side of the stator, sealing rings are arranged between the sealing sleeves and the inner wall surface of the shell, and sealing rings are arranged between the sealing rings and the inner wall surface of the shell.

Through adopting above-mentioned technical scheme, can make fluid pass through stator winding's hollow fluid passageway, cool off stator winding from stator winding's inside, the cooling effect is better.

Drawings

Fig. 1 shows a schematic structural view of an electric machine having a cooling structure according to an embodiment of the present application.

Fig. 2 and 3 show partial schematic views of a stator of an electric machine having a cooling structure according to an embodiment of the present application.

Fig. 4 and 5 show a schematic structural view of a wire of a stator of an electric machine having a cooling structure according to an embodiment of the present application.

Fig. 6 and 7 show partial schematic views of stators of electric machines with cooling structures of other possible embodiments.

Description of the reference numerals

1 Shell 11 oil inlet 12 oil drain port

2 Stator 21 stator core 211 stator core slot

22 Stator winding 221 end region of a wire 222 stator winding

23 Oil liquid channel 24 insulating paper 25 sealing sleeve 26 sealing ring 27 sealing ring

3 Rotor 31 bearing

4. End cap

5. Three phase line

S-shaped sealing space

Aaxial C circumferential R radial

Detailed Description

To more clearly illustrate the above objects, features and advantages of the present application, specific embodiments of the present application are described in detail in this section with reference to the accompanying drawings. The present application can be embodied in various forms other than those described in this section, and modifications, variations, and alternatives thereto can be made by those skilled in the art without departing from the spirit of the application, and therefore the application is not limited to the specific examples disclosed in this section. The protection scope of the present application shall be subject to the claims.

As shown in fig. 1 to 5, an embodiment of the present application proposes an electric machine having a cooling structure, which includes a housing 1, a stator 2, a rotor 3, and an end cover 4.

The housing 1 may have a cylindrical shape with an opening at one end, and the end cap 4 may be connected to the opening of the housing 1 to seal the opening of the housing 1. The stator 2 and the rotor 3 are both disposed inside the housing 1, the rotor 3 is rotatably connected to the housing 1 with respect to the housing 1, and both ends of the rotor 3 can be mounted to the housing 1 and the end cover 4 through bearings 31, respectively. The stator 2 is sleeved on the radial outer side of the rotor 3.

It will be appreciated that the construction of the housing 1 and the end cap 4 is not limited thereto. For example, the housing 1 may be a cylindrical body with both ends open, and both end caps may close both ends of the housing 1 in the axial direction. The rotor 3 here may comprise a rotor shaft.

As shown in fig. 1 and 2, the stator 2 includes a stator core 21 and a stator winding 22, the stator core 21 may be cylindrical formed by stacking a plurality of stator laminations, a stator core groove 211 is formed in an inner peripheral portion of the stator core 21, and the stator core groove 211 penetrates the stator core 21 in an axial direction a of the stator 2. The stator winding 22 is mounted on the stator core 21, and the stator winding 22 is disposed in the stator core slot 211. The stator core grooves 211 are provided in plurality, and the plurality of stator core grooves 211 are uniformly arranged along the circumferential direction C of the stator 2.

The stator winding 22 can be provided with a hollow oil channel 23, oil can flow from one axial end of the stator 2 to the other axial end through the oil channel 23, and the oil flows through the center of the stator winding 22 to cool the stator winding 22, so that the cooling effect is good. Due to the skin effect, current tends to pass through the surface of the conductor, so the hollow stator winding 22 can save material with the same electrical performance.

As shown in fig. 3 to 5, the stator winding 22 may be formed by combining a plurality of (e.g., two) wires 221, and the cross section of the stator winding 22 may be a rectangular frame. The cross-section of the wires 221 may be in the shape of a semi-enclosed "匚" or U-shape with openings, and the openings of the two wires 221 may be joined together in opposition to form the stator winding 22 with the oil passage 23. The stator winding 22 formed by splicing the two wires 221 is easy to manufacture and low in cost. In the cross section of the wire 221, the area ratio of the solid portion of the wire 221 surrounding the oil passage 23 to the oil passage 23 may be 0.4 to 3.

The wire 221 may be made of a metallic conductor material, such as copper or copper alloy. The stator winding 22 may be wrapped with insulating paper 24 and subjected to a varnish treatment, which fills the voids with varnish to eliminate air bubbles and improve the thermal and insulating properties of the stator winding 22.

The stator winding 22 may be a hairpin winding, the stator winding 22 being connected to three phase wires 5, the three phase wires 5 being extendable from the interior of the housing 1 through the end cap 4. In each stator core slot 211, a plurality of stator windings 22 may be accommodated, the plurality of stator windings 22 being arranged in the radial direction R of the stator 2.

Gaps between the two stator windings 22, between the stator windings 22 and the insulating paper 24 and between the insulating paper 24 and the stator core slots 211 are very small, only a small amount of oil flows along the axial direction a through the gaps, and most of the oil flows through the oil channels 23, so that the stator windings are cooled from the inside of the stator windings 22, and the cooling effect is good.

It will be appreciated that although the stator winding 22 of the above embodiment is formed by combining two wires 221, the stator winding 22 may be integrally formed. The specific shapes of the stator winding 22 and the oil liquid channel 23 are not limited in the application, and can be rectangular, circular, elliptic and the like, so long as the stator winding can form a hollow oil liquid channel.

As shown in fig. 1, the casing 1 may be provided with an oil inlet 11 and an oil outlet 12, the oil inlet 11 and the oil outlet 12 may be located at two ends of the stator 2, respectively, and oil may flow into the casing 1 from the oil inlet 11 and flow out of the casing 1 from the oil outlet 12.

The end region 222 of the stator winding 22 may be formed with a sealed space S, which may be located radially outside the rotor 3 in the radial direction R of the motor. The two sealing spaces S are respectively communicated with the oil inlet 11 and the oil outlet 12, the oil liquid channel 23 can be communicated with the sealing spaces S at the two axial ends of the stator winding 22, and the sealing spaces S can reduce leakage and pressure drop of oil liquid in the flowing process. Specifically, seal sleeves 25 may be provided at both axial ends of the stator 2, seal rings 26 may be provided between the seal sleeves 25 and the inner wall surface of the housing 1, and seal rings 27 may be provided between the seal rings 26 and the inner wall surface of the housing 1.

When cooling the stator 2, oil may flow from the oil inlet 11 into the sealed space S at one axial end (right end in fig. 1) of the stator 2, then flow through the oil passage 23 of the stator winding 22 to the sealed space S at the other axial end (left end in fig. 1) of the stator 2, and then flow out of the housing 1 through the oil drain 12. The oil can cool the stator winding 22 from the inside thereof, and the cooling effect is good.

The motor with the cooling structure of the present application includes the following advantageous effects.

(1) The oil can pass through the hollow oil channel 23 of the stator winding 22, and the stator winding 22 is cooled from the inside of the stator winding 22, so that the cooling effect is better.

(2) The stator winding 22 can conduct both current and oil, and thus, no separate components or features are required to conduct oil, resulting in a motor that is simple in construction and easy to manufacture.

(3) Due to the skin effect, current tends to pass through the surface of the conductor, so the hollow stator winding 22 can save material with the same electrical performance.

(4) An existing motor stator insulation design can be employed without additional insulation design.

It should be understood that the above-described embodiments or examples are illustrative only and not limiting. Various variations or modifications of the above-described embodiments or examples are within the spirit of the application and are still within the scope of the application.

The cross section of each wire is not limited to a semi-surrounding shape with an opening, and as shown in fig. 6 and 7, part of the wires may be common solid wires, which may be located at two ends of the stator core slot 211 in the radial direction, or two wires may be alternately arranged.

The present application is not limited to the case where the openings of two wires 221 are oppositely surrounded to form the oil passage 23, as shown in fig. 6, the openings of the wires 221 may be oriented in the same direction, the wires 221 may be surrounded to form the oil passage 23 with the planar portions of the adjacent wires, the cross sections of the adjacent wires may be semi-enclosed shapes having the openings, and the adjacent wires may be common solid wires. As shown in fig. 7, the wires 221 may also enclose the oil passages 23 with the stator core 21 or an insulating member within the stator core 21, and the openings of the wires 221 may be oriented in opposite directions or in the same direction, and in the illustrated example, the openings of adjacent wires are oriented in opposite directions.

It is to be understood that at least some aspects or features of the above-described implementations, embodiments or examples may be combined as appropriate.

It is to be understood that in the present application, when the number of parts or members is not particularly limited, the number may be one or more, and the number herein refers to two or more. For the case where the number of parts or members is shown in the drawings and/or described in the specification as a specific number such as two, three, four, etc., the specific number is generally illustrative and not restrictive, it can be understood that a plurality, i.e., two or more, is plural, but this does not mean that the present application excludes one.

In the present application, unless explicitly stated or limited otherwise, terms such as "mounted," "assembled," "connected," "coupled," "joined," "abutting," "communicating," "conducting," "fixed," "fastened," and the like are to be construed broadly, as they may be, for example, direct or indirect. For example, the connection may be a fixed connection, a detachable connection, or an integral connection; can be mechanically or electrically connected; either directly or indirectly, through intermediaries, or both, may be in communication with each other, or may interact with each other, unless explicitly stated or limited otherwise. For example, the communication/conduction may be direct communication/conduction or indirect communication/conduction via an intermediate medium. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art according to the specific circumstances.

In the present application, unless explicitly stated or defined otherwise, one member is provided/mounted/located/accommodated/placed in/within another member, inside, etc., may be either of the following two cases: a portion or a majority of the one member is located within the other member; and the one member is fully received within the other member.

While the present application has been described in detail using the above embodiments, it will be apparent to those skilled in the art that the present application is not limited to the embodiments described in the present specification. The present application can be modified and implemented as modified embodiments without departing from the spirit and scope of the present application as defined by the claims. Accordingly, the descriptions in this specification are for the purpose of illustration and are not intended to be limiting in any way.

Claims

1. A motor with a cooling structure, comprising:

Housing (1);

a rotor (3) connected to the housing (1) so as to be rotatable relative to the housing (1); and

A stator (2), the stator (2) being sleeved on the radially outer side of the rotor (3), the stator (2) comprising a stator core (21) and a stator winding (22), the stator winding (22) being mounted on the stator core (21), the stator winding (22) being provided with a hollow oil channel (23), the oil channel (23) connecting the two ends of the stator (2) in the axial direction (A), and the oil can flow from one axial end of the stator (2) to the other axial end through the oil channel (23).

2. The motor with a cooling structure according to claim 1, characterized in that the stator winding (22) comprises a plurality of wires (221), and a cross section of one or more of the wires (221) is a semi-enclosed shape with an opening,

The openings of at least two of the conductive wires (221) relatively surround the oil channel (23); and/or at least one of the conductive wires (221) and an adjacent conductive wire, the stator core (21) or an insulating component within the stator core (21) surround the oil channel (23).

3. The motor with a cooling structure according to claim 1 is characterized in that a stator core slot (211) is provided on the inner periphery of the stator core (21), and the stator core slot (211) penetrates the stator core (21) along the axial direction (A) of the stator (2), and there are a plurality of stator core slots (211), and the plurality of stator core slots (211) are evenly arranged along the circumferential direction (C) of the stator (2), and the stator winding (22) is arranged in the stator core slot (211).

4. The motor with a cooling structure according to claim 3 is characterized in that there are multiple oil channels (23) in each of the stator core slots (211), and the multiple oil channels (23) are arranged along the radial direction (R) of the stator (2).

5. The motor with a cooling structure according to claim 1, characterized in that the stator winding (22) is wrapped with insulating paper (24).

6. The motor with a cooling structure according to claim 1 is characterized in that the housing (1) is provided with an oil inlet (11) and an oil outlet (12), and the oil inlet (11) and the oil outlet (12) are respectively located at two ends of the stator (2) in the axial direction (A).

7. The motor with a cooling structure according to claim 6 is characterized in that a sealed space (S) is formed in the end area (222) of the stator winding (22), and the two sealed spaces (S) are respectively connected to the oil inlet (11) and the oil outlet (12), and the oil channel (23) is connected to the sealed spaces (S) at the axial ends of the stator winding (22).

8. The motor with a cooling structure according to claim 7, characterized in that, in the radial direction (R) of the motor, the sealed space (S) is located radially outside the rotor (3).

9. The electric machine with a cooling structure according to claim 1, characterized in that a cross section of the stator winding (22) comprises a hollow rectangle.

10. The motor with a cooling structure according to claim 1 is characterized in that a sealing sleeve (25) is provided at both axial ends of the stator (2) and on the radial inner side of the stator (2), a sealing ring (26) is provided between the sealing sleeve (25) and the inner wall surface of the housing (1), and a sealing ring (27) is provided between the sealing ring (26) and the inner wall surface of the housing (1).