WO2025139623A1 - Driving electric motor having end of stator winding subjected to immersion cooling, power assembly, and electric vehicle - Google Patents

Abstract

Provided in the embodiments of the present application are a driving electric motor having one end of a stator winding subjected to immersion cooling, a power assembly, and an electric vehicle. The driving electric motor comprises: a stator core, a stator winding and a cooling cover. The stator core is used for fixing the stator winding. Along the axial direction of the driving electric motor, one winding end of the stator winding is exposed out of one end of the stator core. Along the radial direction of the driving electric motor, the inner diameter of one winding end of the stator winding is larger than the inner diameter of the stator core. The cooling cover is used for accommodating a cooling liquid and one winding end. The cooling cover comprises a first annular wall, wherein along the radial direction of the driving electric motor, the outer diameter of the first annular wall is less than or equal to the inner diameter of one winding end of the stator winding. The first annular wall faces one end of the stator core along the axial direction of the driving electric motor and is used for enclosing said end of the stator core to form an accommodating structure. The cooling liquid accommodated in the accommodating structure is used for immersion cooling of one winding end of the stator winding. The embodiments of the present application can perform good heat dissipation on the stator winding.

Description

Stator winding end immersion cooling for electric drives, powertrains and electric vehicles

This application claims priority to the Chinese patent application filed with the China Patent Office on December 29, 2023, with application number 202311872048.7 and application name “Drive motor, powertrain and electric vehicle with immersion cooling of stator winding ends”, the entire contents of which are incorporated by reference into this application.

Technical Field

The present application relates to the field of vehicles, and in particular to a drive motor, a powertrain and an electric vehicle with immersion cooling of stator winding ends.

Background Art

The drive motor of an electric vehicle requires a large current to drive the stator winding, so the drive motor has a high temperature during operation, especially the temperature rise of the stator winding is fast. Overheating of the stator winding will cause the internal resistance of the stator winding to increase and the magnetic properties of the stator silicon steel sheet to decay, so the stator winding becomes an important heat dissipation bottleneck in the motor. In the prior art, oil cooling or water cooling is usually used for the drive motor, but conventional oil cooling or water cooling cannot fully dissipate the heat at the end of the stator winding, thereby affecting the performance of the drive motor and the electric vehicle.

Summary of the invention

The embodiments of the present application provide a drive motor, a power assembly and an electric vehicle with immersion cooling of the stator winding ends, which can effectively dissipate the heat of the drive motor, especially the ends of the stator windings, so that the motor has better performance.

In a first aspect, an embodiment of the present application provides a drive motor with immersion cooling of a stator winding end, comprising a stator core, a stator winding and a cooling hood, wherein the stator core is used to fix the stator winding, and along the axial direction of the drive motor, one winding end of the stator winding is exposed at one end of the stator core, and along the radial direction of the drive motor, the inner diameter of one winding end of the stator winding is larger than the inner diameter of the stator core; the cooling hood is used to contain coolant and one winding end, and the cooling hood comprises a first annular wall, and the outer diameter of the first annular wall along the radial direction of the drive motor is less than or equal to the inner diameter of one winding end of the stator winding; the first annular wall is used to enclose one end of the stator core along the axial direction of the drive motor toward the stator core to form a containing structure, and the containing structure is used to contain coolant and immersion cool one winding end of the stator winding.

In the embodiment of the present application, the cooling cover is designed so that the cooling cover includes a first annular wall for enclosing one end of the stator core, so that a receiving structure for receiving the winding end and the coolant can be formed, thereby realizing immersion cooling of the winding end. Therefore, the embodiment of the present application can make the heat of the stator winding be quickly absorbed and taken away by the coolant, greatly improving the heat dissipation effect of the stator winding, enhancing the temperature uniformity and heat dissipation performance of the drive motor cooling, which is conducive to improving the output of the rated power of the drive motor and extending the duration of its peak power.

In an implementation of the first aspect, the cooling cover includes a second annular wall, and the inner diameter of the second annular wall along the radial direction of the drive motor is larger than the outer diameter of the first annular wall and the outer diameter of one winding end. In this implementation, the cooling cover also includes a second annular wall, and the second annular wall can surround the outer circumference of the first annular wall, and the second annular wall can be connected to the stator core, so that the receiving structure can be an annular groove, so as to achieve good reception of the winding end and the coolant, which is conducive to improving the immersion liquid cooling heat dissipation effect of the winding end.

In an implementation of the first aspect, the drive motor includes a stator housing, the stator housing is used to fix the stator core, the length of the stator housing along the axial direction of the drive motor is greater than the stator core, and the outer diameter of the stator core along the radial direction of the drive motor is less than or equal to the inner diameter of the stator housing; the drive motor includes an end cover, the end cover is used to fix the stator housing, and along the axial direction of the drive motor, an end face of the end cover is arranged opposite to the end face of one end of the stator core. For the drive motor with a stator housing and an end cover, a cooling cover can be used to contain the coolant and the winding end to achieve immersion liquid cooling of the winding end.

In an implementation of the first aspect, the inner circumferential surface of the stator housing is used to fix the first annular wall. The first annular wall may be an independent component, which may be fixedly connected to the inner circumferential surface of the stator housing. This implementation is simple and reliable in structure, and is convenient for assembling the cooling cover, thereby ensuring the performance of the cooling cover.

In an implementation of the first aspect, the inner circumferential surface of the stator housing is used to fix the second annular wall or serve as the second annular wall. The second annular wall may be an independent component; or the second annular wall itself is a part of the inner circumferential surface of the stator housing, or the second annular wall is integrated with the stator housing. This implementation is simple in structure and reliable, and is convenient for assembling the cooling cover and ensuring the performance of the cooling cover.

In an implementation of the first aspect, an end face of the end cover is used to: fix the other end of the first annular wall away from the stator core along the axial direction of the drive motor; or, fix the other end of the second annular wall away from the stator core along the axial direction of the drive motor; or, fix the other end of the first annular wall away from the stator core along the axial direction of the drive motor and fix the other end of the second annular wall away from the stator core along the axial direction of the drive motor. The first annular wall can be an independent component, the second annular wall can be an independent component, and at least one of the first annular wall and the second annular wall can be fixedly connected to the end face of the end cover. This implementation method has a simple and reliable structure, is easy to assemble the cooling hood, and ensures the performance of the cooling hood.

In an implementation of the first aspect, the cooling cover includes an axial bottom wall, and along the axial direction of the drive motor, the axial bottom wall, a winding end, and an end face of one end of the stator core are arranged in sequence. In this implementation, by making the cooling cover also include the axial bottom wall, the axial bottom wall can be connected to or not connected with the first annular wall, and the axial bottom wall can be connected to or not connected with the second annular wall, so that the accommodation structure formed can well accommodate the winding end and the coolant, which is conducive to improving the immersion liquid cooling heat dissipation effect of the winding end.

In an implementation of the first aspect, an end surface of the end cover is used as an axial bottom wall of the cooling hood. The axial bottom wall itself is a part of the end cover, or the axial bottom wall and the end cover are integrated into one. This implementation is simple and reliable in structure, and is convenient for assembling the cooling hood and ensuring the performance of the cooling hood.

In an implementation of the first aspect, the outer peripheral surface of the axial bottom wall is used to fix the second annular wall, and the end surface of the axial bottom wall facing the stator core is used to fix the first annular wall of the cooling cover. The second annular wall can be an independent component, or integrated with other shells (such as stator shells). The first annular wall can be an independent component, or integrated with other shells. The second annular wall can be fixedly connected to the outer peripheral surface of the axial bottom wall, and the first annular wall can be fixedly connected to the end surface of the axial bottom wall. The containment structure formed in this way can well contain the winding end and the coolant, which is beneficial to improve the immersion liquid cooling heat dissipation effect of the winding end. This implementation method can be simply and reliably designed to realize the structural design of the cooling cover and ensure the performance of the cooling cover.

In an implementation of the first aspect, the end surface of the axial bottom wall facing the stator core is used to fix the second annular wall of the cooling cover. The second annular wall can be an independent component, or integrated with other housings (such as stator housings). This implementation can be designed simply and reliably, realize the structural design of the cooling cover, and ensure the performance of the cooling cover.

In an implementation of the first aspect, the drive motor includes a plurality of stator cooling channels, and the stator cooling channels include a plurality of coolant outlets, wherein: along the circumference of the drive motor, the plurality of coolant outlets are spaced apart on the end surface of one end of the stator core, and along the radial direction of the drive motor, the distance between each coolant outlet and the axis of the drive motor is greater than the outer diameter of one winding end; along the radial direction of the drive motor, the outer diameter of the second annular wall is greater than the distance between at least part of the coolant outlet and the axis of the drive motor. For the drive motor with the stator cooling channel, the second annular wall is farther from the motor axis, and the coolant outlet is closer to the motor axis, so as to facilitate the use of the stator cooling channel to pass the coolant into the receiving structure of the cooling cover.

In one implementation of the first aspect, the second annular wall includes an opening, and the opening is used to connect to the housing flow channel of the drive motor; wherein the opening faces the axis of the drive motor, and the opening, a winding end, and the end face of one end of the stator core are arranged in sequence along the axial direction of the drive motor. By providing an opening on the second annular wall, the receiving structure and the housing flow channel can be connected, so that the coolant for cooling the winding end can flow through the housing flow channel to other links to be cooled, so that the heat dissipation of the stator winding is no longer the heat dissipation end point of the entire powertrain, and the recovery and reuse of the coolant can be achieved. In addition, without increasing the flow rate of the drive pump, more coolant can be allowed to flow through the stator winding at the same time, thereby enhancing the heat dissipation of the stator winding.

In one implementation of the first aspect, the axial bottom wall includes an opening, and the opening is used to connect to the housing flow channel of the drive motor; wherein the opening faces an end face of the stator core, and is arranged in sequence along the axial opening of the drive motor and a winding end, and the distance between the radial opening of the drive motor and the axis of the drive motor is greater than the distance between the first annular wall and the axis. By providing an opening on the axial bottom wall, the receiving structure and the housing flow channel can be connected, so that the coolant for cooling the winding end can flow through the housing flow channel to other links to be cooled, so that the heat dissipation of the stator winding is no longer the heat dissipation end point of the entire powertrain, and the recovery and reuse of the coolant can be achieved. In addition, more coolant can be allowed to flow through the stator winding at the same time without increasing the flow rate of the drive pump, thereby enhancing the heat dissipation of the stator winding.

In a second aspect, an embodiment of the present application provides a power assembly, including a reducer and the drive motor, wherein the input shaft of the reducer is used to fix the motor shaft connected to the drive motor.

In the embodiment of the present application, by designing the cooling cover of the drive motor, the cooling cover includes a first annular wall enclosing one end of the stator core, and a receiving structure can be constructed, and the receiving structure can receive the winding end and the coolant therein, immersing the winding end in the coolant, and realizing immersion liquid cooling of the winding end. Therefore, the embodiment of the present application can make the heat of the stator winding be quickly absorbed and taken away by the coolant, greatly improving the heat dissipation effect of the stator winding, and enhancing the temperature uniformity of the drive motor cooling, which is conducive to improving the performance of the drive motor and the powertrain.

On the third aspect, an embodiment of the present application provides an electric vehicle, including a frame and the powertrain, wherein the frame is used to fix the powertrain. In an embodiment of the present application, by designing the cooling cover of the drive motor, the cooling cover includes a first annular wall enclosing one end of the stator core, and a receiving structure can be constructed, and the receiving structure can accommodate the winding end and the coolant therein, immersing the winding end in the coolant, and realizing immersion liquid cooling of the winding end. Therefore, the embodiment of the present application can make the heat of the stator winding be quickly absorbed and carried away by the coolant, greatly improving the heat dissipation effect of the stator winding, and enhancing the temperature uniformity of the drive motor cooling, which is beneficial to improving the performance of the drive motor, the powertrain and the whole vehicle.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a schematic structural diagram of an electric vehicle according to an embodiment of the present application;

FIG2 is a schematic diagram of the framework structure of the powertrain of an embodiment of the present application;

FIG3 is a schematic diagram of a three-dimensional structure of a stator core according to an embodiment of the present application;

FIG4 is a schematic diagram of the axial structure of the stator core in FIG3 ;

FIG5 is a schematic diagram of the three-dimensional structure of the cooling cover in Embodiment 1 of the present application at a viewing angle;

FIG6 is a schematic diagram of the three-dimensional structure of the cooling cover in Embodiment 1 of the present application from another perspective;

7 is a cross-sectional schematic diagram of the assembly structure of the cover body, stator core, stator winding, etc. in the first embodiment of the present application;

FIG8 is a schematic diagram of a partial enlarged structure of point A in FIG7;

FIG9 is another partial enlarged structural schematic diagram of point A in FIG7;

10 is a cross-sectional schematic diagram of the assembly structure of the cover body, stator core, stator winding, etc. in the second embodiment of the present application;

FIG11 is a schematic diagram of the three-dimensional structure of the cooling cover in Embodiment 3 of the present application from a viewing angle;

FIG12 is a schematic diagram of the three-dimensional structure of the cooling cover in Embodiment 3 of the present application from another perspective;

13 is a schematic cross-sectional view of the assembly structure of the cover body, stator core, stator winding, etc. in the third embodiment of the present application;

FIG14 is a schematic diagram of the three-dimensional structure of the cooling cover in the fourth embodiment of the present application at a viewing angle;

FIG15 is a schematic diagram of the three-dimensional structure of the cooling cover in the fourth embodiment of the present application from another perspective;

16 is a schematic cross-sectional view of the assembly structure of the cover body, stator core, stator winding, etc. in the fourth embodiment of the present application;

FIG. 17 is a schematic diagram of the topological architecture of the assembly flow passage of the power assembly in the fifth embodiment of the present application;

FIG18 is a schematic cross-sectional view of the structure of the assembly flow channel based on the topological structure shown in FIG17;

FIG. 19 is a schematic diagram of the topological architecture of the assembly flow passage of the power assembly in the sixth embodiment of the present application;

FIG20 is a schematic cross-sectional view of the assembly flow channel based on the topological structure shown in FIG19;

FIG21 is a schematic diagram of the topological architecture of the assembly flow channel of the power assembly in the seventh embodiment of the present application;

FIG22 is a schematic cross-sectional view of the structure of the assembly flow channel based on the topological structure shown in FIG21;

FIG23 is a schematic diagram of the topological architecture of the assembly flow channel of the power assembly in the eighth embodiment of the present application;

FIG24 is a schematic cross-sectional view of the structure of the assembly flow channel based on the topological structure shown in FIG23;

FIG25 is a schematic diagram of the topological architecture of the assembly flow channel of the power assembly in the ninth embodiment of the present application;

FIG. 26 is a schematic diagram of the cross-sectional structure of the assembly flow channel based on the topological structure shown in FIG. 25 .

DETAILED DESCRIPTION

For ease of understanding, the relevant technical terms involved in the embodiments of the present application are explained and described below.

In the description of the embodiments of the present application, unless otherwise specified, “plurality” refers to two or more.

The terms "first", "second", etc. are used for descriptive purposes only and should not be understood to imply or suggest relative importance or implicitly indicate the number of technical features indicated. Features qualified as "first" or "second" may explicitly or implicitly include one or more of the features.

The directional terms mentioned in the embodiments of the present application, such as "upper", "lower", "front", "back", "left", "right", "inner", "outer", "side", "top", "bottom", etc., are only reference directions of the drawings. The directional terms are for better and clearer explanation and understanding of the embodiments of the present application, and do not explicitly or implicitly indicate that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, etc., and therefore cannot be understood as limiting the embodiments of the present application.

The embodiments of the present application provide an electric vehicle, including but not limited to an electric sedan, an electric SUV (Sport Utility Vehicle), an electric bus, an electric motorcycle, etc. The electric vehicle can be a pure electric vehicle, a hybrid vehicle, or a fuel cell vehicle, etc.

FIG1 schematically shows an electric vehicle 1 , which may include a vehicle frame 2 , a thermal management system 3 , a power assembly 4 , etc. The thermal management system 3 and the power assembly 4 may be installed on the vehicle frame 2 .

The powertrain 4 is a system composed of a series of components for generating power and transmitting the power to the road surface. The powertrain 4 can drive the wheels to rotate. Schematically, the electric vehicle 1 may also include a power battery, which is used to provide electrical energy to the powertrain 4, and the powertrain 4 converts the electrical energy into mechanical energy and drives the wheels to rotate. The thermal management system 3 is used to perform thermal management of the entire vehicle. Thermal management may include heat dissipation (e.g., heat dissipation of the power battery and the powertrain), heating (e.g., heating the power battery and the drive motor), air conditioning, temperature control (e.g., monitoring and adjusting the operating temperature of the power battery and the drive motor), heat distribution (e.g., ensuring the temperature stability and balance of the power battery and the drive motor), and other processes. The heat exchanger in the powertrain 4 may be connected to the thermal management system 3, and the powertrain 4 may perform heat exchange with the thermal management system 3 through the heat exchanger.

FIG. 2 illustrates a framework structure of a power assembly 4 . It is understandable that the positions and connections of the various components in FIG. 2 are merely schematic and are not intended to limit the actual structure.

As shown in Fig. 2, the power assembly 4 may include a drive motor 6, a motor controller 7, a reducer 8, a drive pump 9, a filter 10, a heat exchanger 5, etc. In the embodiment of the present application, the drive motor 6 may be a radial motor.

In one embodiment, the power assembly 4 may be an integrated power assembly, and the drive motor 6, the motor controller 7, the reducer 8, etc. may be assembled in the same assembly housing. The drive motor accommodating chamber of the housing of the power assembly 4 is used to accommodate the drive motor 6. The controller accommodating chamber of the housing of the power assembly 4 is used to accommodate the motor controller 7. The reducer accommodating chamber of the housing of the power assembly 4 is used to accommodate the reducer 8. For ease of naming, the housing portion accommodating the drive motor 6 may be referred to as a motor housing, the housing portion accommodating the motor controller 7 may be referred to as a motor controller housing, and the housing portion accommodating the reducer 8 may be referred to as a reducer housing.

In one embodiment, the power assembly 4 may also be a split power assembly, wherein one or more of the drive motor 6, the motor controller 7 and the reducer 8 has a separate housing.

As shown in FIG2 , the motor controller 7 is used to control the drive motor 6. The motor controller 7 is used to receive direct current from the power battery and output alternating current to the drive motor 6. The motor shaft of the drive motor 6 is drivingly connected to the input shaft of the reducer 8, and the drive motor 6 transmits the power of the drive motor 6 to the wheels through the reducer 8.

As shown in Fig. 2, the driving pump 9 is installed in the pump accommodating chamber of the housing of the power assembly 4, and the driving pump is used to drive the coolant to circulate between the internal flow channel of the housing of the power assembly 4, the coolant flow channel of the driving motor 6, and the coolant flow channel of the reducer 8. In one embodiment, the coolant can be cooling oil.

As shown in FIG2 , the heat exchanger 5 is mounted on the housing of the powertrain 4 and is connected to at least one of the internal flow channel of the housing of the powertrain 4, the coolant flow channel of the drive motor 6, or the coolant flow channel of the reducer 8. The heat exchanger 5 is used to dissipate heat from at least one of the internal flow channel of the housing of the powertrain 4, the coolant flow channel of the drive motor 6, or the coolant flow channel of the reducer 8.

As shown in FIG. 2 and FIG. 1 , the coolant absorbs heat and rises in temperature after flowing through at least one of the internal flow channel of the housing of the power assembly 4, the coolant flow channel of the drive motor 6, or the coolant flow channel of the reducer 8. The heat-absorbing and heated coolant can be cooled by heat exchange with the thermal management system 3 through the heat exchanger 5. Thus, the coolant can circulate in the power assembly 4 and circulate and cool the power assembly 4. The above circulated cooling process will be further described below.

As shown in FIG2 , the filter 10 is installed on the housing of the powertrain 4. The filter 10 is used to filter foreign matter and impurities in at least one of the internal flow channel of the housing of the powertrain 4, the coolant flow channel of the drive motor 6, or the coolant flow channel of the reducer 8. In one embodiment, the filter 10 is located upstream of the drive pump 9. In one embodiment, the filter 10 is located downstream of the drive pump 9. In one example, the filter 10 is located between the drive pump 9 and the heat exchanger 5.

It is understandable that the powertrain 4 shown in FIG. 2 is only one embodiment of the powertrain 4 provided in the embodiment of the present application. The powertrain 4 may include more or fewer components as required. In another embodiment, the powertrain 4 may not include the filter 10.

In the drive motor 6 and the powertrain 4 provided in the embodiment of the present application, by improving the heat dissipation design of the stator winding of the drive motor 6, not only can the stator winding be fully dissipated, but the coolant of the stator winding can also be used to cool other heat-generating components of the powertrain 4, thereby realizing the recycling and reuse of the coolant. In addition, in the drive motor 6 and the powertrain 4 provided in the embodiment of the present application, the heat generated by the stator winding can also be effectively collected and transported to the thermal management system to reduce heat loss, thereby improving the coefficient of performance (COP, the ratio of the heat output generated to the electrical energy consumed), and achieving energy saving and cost reduction. This will be described in detail below.

In the embodiment of the present application, the axial direction, circumferential direction and radial direction are defined based on the motor shaft of the drive motor 6. The axial direction of the drive motor 6 is parallel to the length direction of the motor shaft, the circumferential direction of the drive motor 6 is the circumferential direction around the motor shaft, and the radial direction of the drive motor 6 is parallel to the diameter direction of the motor shaft.

In an embodiment of the present application, the drive motor 6 includes a stator core and a stator winding. The stator core is used to fix the stator winding. One winding end of the stator winding along the axial direction of the drive motor 6 is exposed at one end of the stator core, and the inner diameter of one winding end of the stator winding along the radial direction of the drive motor 6 is larger than the inner diameter of the stator core.

FIG3 and FIG4 show a schematic structure of the stator core 61 in the drive motor 6. As shown in FIG3 and FIG4, the end faces of the stator core 61 at both ends along the axial direction are end face 61c and end face 61e respectively. A plurality of wire slots 61a are provided on the inner circumference of the stator core 61. These wire slots 61a can be distributed at equal intervals along the circumference. Each wire slot 61a can penetrate the two opposite end faces 61c and end face 61e of the stator core 61. Each wire slot 61a can form an opening on the inner circumference of the stator core 61. A wire can be embedded in each wire slot 61a to form a stator winding. The axial length of the stator winding can be greater than the axial length of the stator core 61. The opposite ends of the stator winding along the axial direction can be exposed to the end faces of the stator core 61 at both ends along the axial direction. These two ends can be respectively referred to as the first winding end and the second winding end (to be described below). The first winding end and the second winding end are both winding ends. The inner circumferential surface of the winding end in the wire slot 61 a may be sunken by a certain distance relative to the opening of the wire slot 61 a , so that the inner diameter of the winding end is larger than the inner diameter of the stator core 61 .

In some embodiments, each wire groove 61 a may also be used to circulate a cooling liquid (described below).

In this embodiment, the drive motor 6 includes a plurality of stator cooling channels, and the stator cooling channels include a plurality of coolant outlets, wherein: the plurality of coolant outlets are spaced apart on the end surface of one end of the stator core 61 along the circumference of the drive motor 6, and the distance between each coolant outlet and the axis of the drive motor 6 along the radial direction of the drive motor 6 is greater than the outer diameter of the winding end.

For example, as shown in FIG. 3 and FIG. 4 , a plurality of axial channels 61b may be provided in the stator core 61, and these axial channels 61b may be equally spaced along the circumferential direction, and each axial channel 61b may extend along the axial direction and penetrate the end surface 61c and the end surface 61e, and form a coolant outlet on the end surface 61c and the end surface 61e, respectively. The multiple coolant outlets on each of the end surfaces 61c and 61e may be spaced along the circumference of the drive motor 6. Compared with the wire slot 61a, the axial channel 61b may be closer to the outer periphery of the stator core 61, so the distance between each coolant outlet and the axis of the drive motor 6 is greater than the outer diameter of the winding end.

Illustratively, a circumferential channel 61d may be provided on the outer circumferential surface of the stator core 61. The circumferential channel 61d may be a groove that surrounds the circumference. The circumferential channel 61d is connected to each axial channel 61b.

In another embodiment, the circumferential channel 61d may also be composed of a plurality of radial holes arranged in sequence and spaced apart along the circumferential direction, the axis of each radial hole is along the radial direction, and one radial hole may be correspondingly connected to one axial channel 61b.

In the embodiment of the present application, the axial channel 61b and the circumferential channel 61d are all stator cooling channels.

As shown in FIG. 3 and FIG. 4 , a sealing layer 62 may be provided on the inner circumferential surface of the stator core 61 .

In one embodiment, the sealing layer 62 may cover all areas of the inner circumference of the stator core 61, and the sealing layer 62 may be a single cylindrical component. The sealing layer 62 covers the opening of each wire slot 61a on the inner circumference of the stator core 61, so that the wires in each wire slot 61a are contained in the space surrounded by the slot wall of the wire slot 61a and the sealing layer 62. Schematically, the sealing layer 62 may be integrated with the stator core 61, for example, the sealing layer 62 may be manufactured on the inner circumference of the stator core 61 using an injection molding process. Alternatively, the sealing layer 62 may be manufactured separately and assembled to the stator core 61.

Different from the above, in another embodiment, there may be multiple sealing layers 62, each of which may be in the shape of an arc-shaped plate. These sealing layers 62 may be evenly spaced along the inner circumference of the stator core 61, and one sealing layer 62 may correspond to covering the opening of one wire slot 61a.

The following description will be continued by taking the sealing layer 62 as a single cylindrical component as an example.

In the embodiment of the present application, cooling covers can be connected to both opposite ends of the axial direction of the stator core 61 to achieve immersion liquid cooling of the stator winding. The cooling cover is used to contain the coolant and a winding end, and the cooling cover includes a first annular wall, the outer diameter of the first annular wall along the radial direction of the drive motor 6 is less than or equal to the inner diameter of one winding end of the stator winding, and the first annular wall along the axial direction of the drive motor 6 is used to enclose one end of the stator core 61 to form a containing structure, and the coolant contained in the containing structure is used to immerse and cool the winding end.

In the embodiment of the present application, one cooling cover is used to contain coolant and one winding end, and the other cooling cover is used to contain coolant and another winding end.

In the embodiment of the present application, the first annular wall of the cooling cover is around a circle, and the radial dimension of the first annular wall can be defined as the dimension along the radial direction of the drive motor 6. The first annular wall has a certain thickness, so the inner diameter and the outer diameter can be defined, wherein the outer diameter of the first annular wall is the radial dimension of the outer circumference of the first annular wall away from the axis of the drive motor 6. The outer diameter of the first annular wall is less than or equal to the inner diameter of the winding end, that is, the inner circumference of the winding end, the outer circumference of the first annular wall and the axis of the drive motor 6 can be arranged in sequence along the radial direction of the drive motor 6, and there is a certain distance between the inner circumference of the winding end and the outer circumference of the first annular wall, or there is basically no gap between the inner circumference of the winding end and the outer circumference of the first annular wall.

In an embodiment of the present application, the first annular wall can be used to enclose one end of the stator core 61, and the cooling cover can form a receiving structure for receiving a winding end and coolant, thereby achieving immersion cooling of the winding end.

Several cooling hood design options are described below with examples.

Figures 5 and 6 show the schematic structure of the cooling cover 63 in the first embodiment of the present application. As shown in Figures 5 and 6, the cooling cover 63 can be a substantially annular cover body.

The cooling cover 63 may include a first annular wall 63c, an axial bottom wall 63b and a second annular wall 63a, which are connected in sequence. The axial bottom wall 63b may be approximately annular, and may enclose a first through hole 63d; the second annular wall 63a and the first annular wall 63c may both be convexly disposed on the axial bottom wall 63b, and may respectively connect the outer edge and the inner edge of the axial bottom wall 63b, the second annular wall 63a may be located on the outer periphery of the first annular wall 63c, and the first annular wall 63c may surround the outer periphery of the first through hole 63d. The second annular wall 63a, the axial bottom wall 63b and the first annular wall 63c may enclose an annular groove.

As shown in FIG. 7 , along the axial direction of the drive motor, the axial bottom wall 63 b of the cooling cover 63 , one winding end 65 a and the end surface 61 c of one end of the stator core 61 are arranged in sequence.

In the embodiment of the present application, any one of the axial bottom wall 63b, the first annular wall 63c and the second annular wall 63a of the cooling cover 63 can be independent of the motor housing, or integrated with the motor housing. The types of the axial bottom wall 63b, the first annular wall 63c and the second annular wall 63a can be freely combined according to product requirements.

In the first embodiment, a cooling cover 64 may be further designed, and the structure of the cooling cover 64 may be consistent with that of the cooling cover 63, and the two may be arranged in a mirror image, as will be described below.

FIG7 illustrates the assembly cross-sectional structure of the stator core 61, the stator winding 65, the sealing layer 62, the cooling cover 63 and the cooling cover 64 in the first embodiment. As shown in FIG7, the stator winding 65 includes a winding end 65a and a winding end 65b, and the winding end 65a and the winding end 65b are both exposed at one end surface of the stator core 61. The cooling cover 63 and the cooling cover 64 can be respectively located at opposite ends of the stator winding 65 in the axial direction, the axial bottom wall 63b and the second bottom wall 64b are arranged in reverse, and the second annular wall 63a and the second annular wall 64a are arranged facing each other. The second bottom wall 64b can enclose a second through hole.

As shown in FIG. 7 , the inner diameter r1 of the second annular wall 63 a in the radial direction of the drive motor 6 is larger than the outer diameter r3 of the first annular wall 63 c and the outer diameter r2 of one winding end portion 65 a .

As shown in reference figure 7, the outer diameter of the second annular wall along the radial direction of the drive motor 6 is greater than the distance between at least part of the coolant outlet and the axis of the drive motor 6. For example, the outer diameter r4 of the second annular wall 64a is greater than the distance d1 between the coolant outlet of at least part of the axial channel 61b and the axis of the drive motor 6. As shown in Figure 7, the second annular wall 63a of the cooling cover 63 can be connected to the end face 61c of the stator core 61. Schematically, the second annular wall 63a can be connected to the end face 61c through a sealing structure, and the sealing structure is made of a material with good sealing performance. The sealing structure can be, for example, a sealing ring. Alternatively, the second annular wall 63a can be directly connected to the end face 61c without passing through a connecting medium. The second annular wall 63a is far away from the stator winding 65, while the axial channel 61b is close to the stator winding 65. The first annular wall 63c of the cooling cover 63 can be connected to the sealing layer 62. Thus, the winding end 65a is encapsulated in the first end flow channel 6a surrounded by the cooling cover 63, the stator core 61 and the sealing layer 62. All axial channels 61b can be connected to the first end flow channel 6a. The first end flow channel 6a can also be called a receiving structure.

As shown in FIG7 , schematically, the second annular wall 64a of the cooling cover 64 can be connected to the end face 61c of the stator core 61. Schematically, the second annular wall 64a can be connected to the end face 61c through a sealing structure, and the sealing structure is made of a material with good sealing performance. The sealing structure can be, for example, a sealing ring. Alternatively, the second annular wall 64a can be directly connected to the end face 61c without passing through a connecting medium. The second annular wall 64a is far away from the stator winding 65, while the axial channel 61b is close to the stator winding 65. The first annular wall 64c of the cooling cover 64 can be connected to the sealing layer 62. As a result, the winding end 65b is encapsulated in the second end flow channel 6b surrounded by the cooling cover 64, the stator core 61 and the sealing layer 62. The second end flow channel 6b can also be called a receiving structure.

All the axial passages 61b can be communicated with the second end flow passage 6b, and therefore, the second end flow passage 6b can be communicated with the first end flow passage 6a through the axial passages 61b.

FIG8 is a partial enlarged structural schematic diagram of A in FIG7 , and FIG8 can represent a connection mode between the first annular wall 63c of the cooling cover 63 and the sealing layer 62. As shown in FIG8 , the first annular wall 63c and the sealing layer 62 can be distributed along the axial direction, and the two can be connected by a sealing structure 66. The sealing structure 66 is made of a material with good sealing performance. Schematically, the sealing structure 66 can be a sealing ring.

Different from that shown in FIG8 , in another embodiment, as shown in FIG9 , the first annular wall 63c and the sealing layer 62 may be distributed in the radial direction, and the two may be connected by a sealing structure 66. In the embodiment shown in FIG9 , the first annular wall 63c is connected to the inner circumference of one end of the stator core 61 through the sealing layer 62. Accordingly, the connection area between the first annular wall 63c and the sealing layer 62 is large, so that the airtightness of the first end flow channel 6a is better. In other embodiments, the first annular wall 63c and the sealing layer 62 may be directly connected without a connecting medium.

The connection between the first annular wall 64c of the cooling cover 64 and the sealing layer 62 may also be carried out in the manner described above, which will not be described in detail here.

In this embodiment, the first end flow channel 6a and the second end flow channel 6b can both be used as flow channels for the coolant, and both can be connected to the drive pump 9, the filter 10, the heat exchanger 5 and other flow channels in the power assembly 4. The first end flow channel 6a and the second end flow channel 6b can both flow in and contain the coolant, so that the two ends of the stator winding 65 can be immersed in the coolant in the first end flow channel 6a and the second end flow channel 6b, respectively, to achieve immersion liquid cooling heat dissipation. The above will be further explained below.

In this embodiment, the cooling cover 63, the cooling cover 64 and the motor housing can be independent of each other, and the cooling cover 63 and the cooling cover 64 are not directly connected to the motor housing. Schematically, the drive motor 6 can be an ear-hanging motor, and the outer periphery of the stator core 61 can have a stator ear, and the cooling cover 63 and the cooling cover 64 can form a cover body ear, and the cover body ear is assembled with the stator ear, and the stator ear is fixed to the motor housing, so that the cooling cover 63, the cooling cover 64 and the stator core 61 are fixed to the same position of the motor housing. In one embodiment, the cooling cover 63, the cooling cover 64 and the motor housing are independent of each other, but the cooling cover 63 and the cooling cover 64 are connected to the motor housing, which will be explained below.

As shown in FIG10 , the drive motor 6 includes a stator housing 6x, which is used to fix the stator core 61. The length of the stator housing 6x along the axial direction of the drive motor 6 is greater than the stator core 61, and the outer diameter of the stator core 61 along the radial direction of the drive motor 6 is less than or equal to the inner diameter of the stator housing 6x. The drive motor 6 also includes an end cover, which is used to fix the stator housing 6x, and one end face of the end cover along the axial direction of the drive motor 6 is arranged opposite to the end face of one end of the stator core 61.

As shown in FIG10 , the stator housing 6x surrounds the outer circumference of the stator core 61 and is used to fix the stator core 61. Along the axial direction of the drive motor 6, one end (e.g., the left end) of the stator housing 6x, one end (e.g., the left end) of the stator core 61, the other end (e.g., the right end) of the stator core 61, and the other end (e.g., the right end) of the stator housing 6x can be arranged in sequence. The end cover can include a first end cover 67 and a second end cover 68. The outer circumferential surface of the end cover is used to fix the inner circumferential surface of the stator housing 6x, or the end surface of the end cover is used to fix the end surface of the stator housing 6x.

10 illustrates an assembled cross-sectional structure of the stator housing 6x, the first end cover 67, the stator core 61, the stator winding 65, the sealing layer 62, the cooling cover 63, the cooling cover 64 and the second end cover 68 in the second embodiment.

Among them, the first end cover 67 and the second end cover 68 both belong to the motor housing. The first end cover 67 can be located on the side of the cooling cover 63 facing away from the cooling cover 64, and the first end cover 67 can be assembled with the cooling cover 63, for example, by a threaded connector. The first end cover 67 can press the cooling cover 63 so that the cooling cover 63 forms a sealed connection with the stator core 61 and the sealing layer 62. The second end cover 68 can be located on the side of the cooling cover 64 facing away from the cooling cover 63, and the second end cover 68 can be assembled with the cooling cover 64, for example, by a threaded connector. The second end cover 68 can press the cooling cover 64 so that the cooling cover 64 forms a sealed connection with the stator core 61 and the sealing layer 62.

In one embodiment, the inner circumference of the stator housing is used to fix the first annular wall. The first annular wall may be an independent component, which may be fixedly connected to the inner circumference of the stator housing. This embodiment does not limit the connection structure between the first annular wall and the inner circumference of the stator housing. For example, the inner circumference of the stator housing may extend a connecting wall in the radial direction, and the connecting wall is connected to the first annular wall to form a receiving structure. This embodiment can realize the assembly of the cooling cover with a simple and reliable structure to ensure the performance of the cooling cover.

In one embodiment, the inner circumferential surface of the stator housing is used to fix the second annular wall or serve as the second annular wall. The second annular wall may be an independent component, which may be fixedly connected to the inner circumferential surface of the stator housing. Alternatively, the stator housing may be integrated with the second annular wall, and at least a portion of the stator housing may be used as the second annular wall. In this way, the cooling cover may be manufactured with a simple and reliable structure, so that the cooling cover can accommodate the coolant and the winding ends.

Referring to Figure 10, in one embodiment, one end surface of the end cover of the drive motor 6 is used to fix the other end of the first annular wall away from the stator core 61 along the axial direction of the drive motor 6; or to fix the other end of the second annular wall away from the stator core 61 along the axial direction of the drive motor 6; or to fix the other end of the first annular wall away from the stator core 61 along the axial direction of the drive motor 6 and to fix the other end of the second annular wall away from the stator core 61 along the axial direction of the drive motor 6.

In this embodiment, the first annular wall and the second annular wall of the cooling hood may be independent components, and at least one of the two may be fixedly connected to an end face of the end cover. The axial bottom wall in the cooling hood may be an independent component, or may be integrated with the end cover. Take the end cover 67 as an example: an end face (e.g., the right end face) of the end cover 67 may be used to fix the end of the first annular wall away from the stator core 61, or an end face (e.g., the right end face) of the end cover 67 may be used to fix the end of the second annular wall away from the stator core 61, or an end face (e.g., the right end face) of the end cover 67 may be used to fix the end of the first annular wall away from the stator core 61 and the end of the second annular wall away from the stator core 61.

In one embodiment of the present application, the cooling cover 63, the cooling cover 64 and the motor housing can be integrated into one, which will be explained below.

FIG. 11 and FIG. 12 illustrate the structure of the cooling cover 63 in the third embodiment. As shown in FIG. 11 and FIG. 12, the cooling cover 63 can be a roughly annular cover body. The cooling cover 63 can include an axial bottom wall 63b, a second annular wall 63a and a first annular wall 63c. Among them, the axial bottom wall 63b can be approximately annular, and a first through hole 63d can be provided thereon, and the first through hole 63d can be used to install the motor shaft; the second annular wall 63a and the first annular wall 63c can both be convexly arranged on the axial bottom wall 63b, and the second annular wall 63a can be located on the outer periphery of the first annular wall 63c, and the second annular wall 63a can be at a certain distance from the edge of the axial bottom wall 63b.

As shown in FIG. 13 , the axial bottom wall 63 b may be integrated with the end cover of the driving motor 6 , and one end surface of the end cover is used as the axial bottom wall 63 b of the cooling cover 63 .

FIG. 13 illustrates an assembled cross-sectional structure of a stator core 61 , a stator winding 65 , a sealing layer 62 , a cooling cover 63 , and a cooling cover 64 in the third embodiment, wherein the structures of the cooling cover 64 and the cooling cover 63 may be consistent.

As shown in Figure 13, the cooling cover 63 can be used as the first end cover, and the cooling cover 64 can be used as the second end cover. The connection method of the cooling cover 63, the cooling cover 64, the stator core 61 and the sealing layer 62 can be as described above, and will not be repeated here. Embodiment 3 By combining the cover body and the end cover of the drive motor into one, the structure can be made compact, the assembly process is simplified, and it is beneficial to improve the assembly accuracy. In other embodiments, at least a portion of the cooling cover 63 can also be the peripheral side shell of the motor housing (a shell surrounding the circumference, and the end cover can be assembled with the peripheral side shell in the axial direction), and at least a portion of the cooling cover 64 can also be the peripheral side shell of the motor housing. The peripheral side shell can also be called a stator housing.

In the fourth embodiment of the present application, different from the third embodiment, a part of the cooling cover 63 and a part of the cooling cover 64 can be integrated with the motor housing, and another part of the cooling cover 63 and another part of the cooling cover 64 can be independent of the motor housing.

FIG14 and FIG15 illustrate the structure of the cooling cover 63 of the fourth embodiment. As shown in FIG14 and FIG15, the cooling cover 63 may include an axial bottom wall 63b and a first annular wall 63c. The axial bottom wall 63b may be approximately annular, and may enclose a first through hole 63d, and the first through hole 63d may be used to allow the motor shaft to pass through; the first annular wall 63c may be convexly disposed on the axial bottom wall 63b, and the first annular wall 63c may have a certain distance from the edge of the axial bottom wall 63b, and the first annular wall 63c surrounds the outer periphery of the first through hole 63d. Comparing FIG14 with FIG11, it can be seen that compared with the third embodiment, the cooling cover 63 of the fourth embodiment may not have a first annular wall.

Figure 16 illustrates the assembled cross-sectional structure of the stator core 61, stator winding 65, sealing layer 62, cooling cover 63, cooling cover 64, peripheral shell 671, first end cover 672 and second end cover 673 in the fourth embodiment, wherein the structure of the cooling cover 64 can be consistent with that of the cooling cover 63.

As shown in FIG16 , the circumferential shell 671 surrounds the outer periphery of the stator core 61, and the circumferential shell 671 can be connected to the outer peripheral surface of the stator core 61. The axial bottom wall 63b of the cooling cover 63 can be connected to the circumferential shell 671, and the circumferential shell 671, the axial bottom wall 63b, the sealing layer 62 and the stator core 61 can form a first end flow channel 6a. Therefore, a part of the circumferential shell 671 can serve as the first annular wall of the cooling cover 63. The second bottom wall 64b of the cooling cover 64 can be connected to the circumferential shell 671, and the circumferential shell 671, the second bottom wall 64b, the sealing layer 62 and the stator core 61 can form a second end flow channel 6b. Therefore, a part of the circumferential shell 671 can serve as the second annular wall of the cooling cover 64.

As shown in Fig. 16, the peripheral shell 671 may be provided with an inlet 671b near the bottom, the inlet 671b may be communicated with the second end flow channel 6b, and the inlet 671b allows the coolant to enter the second end flow channel 6b. The peripheral shell 671 may be provided with an outlet 671a near the top, the outlet 671a may be communicated with the first end flow channel 6a, and the outlet 671a allows the coolant to flow out of the first end flow channel 6a.

Referring to FIG. 7 , in one embodiment, the outer peripheral surface of the axial bottom wall 63b of the cooling cover 63 is used to fix the second annular wall 63a, and the end surface of the axial bottom wall 63b facing the stator core 61 is used to fix the first annular wall 63c of the cooling cover 63. The axial bottom wall 63b can be an independent component, or integrated with the motor housing. The second annular wall 63a can be an independent component, or integrated with the motor housing. The first annular wall 63c can be an independent component, or integrated with the motor housing.

Referring to FIG. 13 and FIG. 7 , in one embodiment, the axial bottom wall 63b of the cooling cover 63 faces the end surface of the stator core 61 and is used to fix the second annular wall 63a of the cooling cover 63. The axial bottom wall 63b can be an independent component, or integrated with the motor housing. The second annular wall 63a can be an independent component, or can be integrated with the motor housing, for example, integrated with the stator housing.

Based on the description of the above embodiments, it can be understood that in the embodiments of the present application, any one of the axial bottom wall, the first annular wall and the second annular wall of the cooling cover can be integrated with the motor housing, or can be independent of the motor housing. Moreover, the types of the bottom wall, the first annular wall and the second annular wall can be freely combined according to product requirements. For example:

For example, in another embodiment, the first annular wall and the axial bottom wall can be integrated with the motor housing, the second annular wall is independent of the motor housing, and the second annular wall can be assembled with the axial bottom wall. The first annular wall can be part of the peripheral shell, and the axial bottom wall can be part of the first end cover.

Alternatively, in another embodiment, the first annular wall and the second annular wall may be integrated with the motor housing, the axial bottom wall is independent of the motor housing, and the axial bottom wall is assembled with the first annular wall and the second annular wall. The first annular wall may be a part of the peripheral shell, and the second annular wall may be a part of the first end cover; or the first annular wall and the second annular wall may be a part of the first end cover.

Or in another embodiment, the second annular wall is integrated with the motor housing, the first annular wall and the axial bottom wall are both independent of the motor housing, and the axial bottom wall is assembled with the second annular wall. The second annular wall may be part of the first end cover. The first annular wall and the axial bottom wall may be connected as a whole or assembled together.

Or in another embodiment, the second annular wall and the axial bottom wall are integrated with the motor housing, the first annular wall is independent of the motor housing, and the first annular wall is assembled with the axial bottom wall. The second annular wall and the axial bottom wall can both be part of the first end cover.

Or in another embodiment, the axial bottom wall is integrated with the motor housing, the first annular wall and the second annular wall are both independent of the motor housing, and the first annular wall and the second annular wall are both assembled with the axial bottom wall. The axial bottom wall may be part of the first end cover.

The above embodiments respectively describe different types of cooling covers, and the types of the cooling cover 63 and the cooling cover 64 in each embodiment can be consistent. In another embodiment, the types of the cooling cover 63 and the cooling cover 64 can be different, and the type of the cooling cover 63 and the type of the cooling cover 64 can be arbitrarily combined as needed. For example, the cooling cover 63 can adopt the type shown in FIG. 7, and the cooling cover 64 can adopt the type shown in FIG. 10 or FIG. 13; or, the cooling cover 63 can adopt the type shown in FIG. 10, and the cooling cover 64 can adopt the type shown in FIG. 7 or FIG. 13.

The above description describes the first end flow channel 6a and the second end flow channel 6b constructed by designing the cooling cover 63 and the cooling cover 64. The following description describes the positions of the first end flow channel 6a and the second end flow channel 6b in the assembly flow channel of the power assembly 4, and describes the immersion heat dissipation principle of the stator winding 65 and the heat dissipation principle of the entire power assembly 4.

In the embodiment of the present application, the first end flow channel 6a and the second end flow channel 6b can both be located in the middle section of the assembly flow channel of the power assembly 4 but can only be located at the end, that is, after the coolant flows through the first end flow channel 6a and the second end flow channel 6b, it can continue to flow into other flow channels in the assembly flow channel, rather than only falling into the bottom shell of the power assembly 4.

FIG17 is a schematic diagram of the topological architecture of the assembly flow channel of the powertrain 4 in the fifth embodiment of the present application. FIG17 illustrates the key parts of the assembly flow channel, but not the entire assembly flow channel. As shown in FIG17, the assembly flow channel may include flow channels in the drive pump, heat exchanger, stator core, cover (including cooling cover and cooling cover), motor shaft, rotor and reducer, etc., as well as flow channels between the above-mentioned components. Among them, the assembly flow channel is surrounded by a physical structure, for example, the assembly flow channel may include a pipeline, a flow channel groove on the casing, etc., and the assembly flow channel is represented by a solid line with an arrow in FIG17. The dotted line with an arrow in FIG17 indicates that the coolant is transported between the bottom shell and the above-mentioned components by spraying, leaking, gear stirring, etc. Among them, the spraying may be, for example, the coolant sprayed out of the bottom shell through a nozzle. Leakage may be, for example, a natural leakage to the bottom shell at the joint of the physical flow channel or the installation position of the internal sensor. Gear agitation is a process in which a part of the gear in the reducer is immersed in the coolant in the bottom shell, and the coolant is transported from the bottom shell to the inside of the reducer through the agitation of the gear.

As shown in Figure 17, the stator core has a stator cooling channel, the cooling cover participates in the formation of the end flow channel (including the first end flow channel and the second end flow channel), and the motor shaft, rotor and reducer participate in the formation of other flow channels. Among them, the other flow channels may include the first channel and the second channel. The first channel is the flow channel in the drive motor other than the end flow channel and the stator cooling channel, such as the motor shaft channel in the motor shaft, the motor bearing accommodating cavity, the rotor channel in the rotor, etc. The second channel is the flow channel in the reducer, such as the gear shaft flow channel in the reducer, etc.

As shown in Figure 17, the driving pump extracts high-temperature coolant from the bottom shell and pumps the high-temperature coolant into the heat exchanger, and the low-temperature coolant flows out of the heat exchanger. The low-temperature coolant can flow into the stator cooling channel, the end channel and other channels in parallel. Among them, the low-temperature coolant can flow into the other channels along the channel R1, flow into the stator cooling channel along the channel R2, and flow into the end channel along the channel R3. The channels R1, R2 and R3 are connected in parallel. The coolant flowing out of the stator cooling channel can also flow into the end channel along the channel R4. The coolant in the end channel can flow into the bottom shell by spraying or leaking (the coolant can flow out from the first end channel or the second end channel and enter the bottom shell). The coolant in the end channel can also flow into the other channel along the channel R5. The coolant in the other channel can flow into the bottom shell by spraying or leaking. For the reducer in the other channel, the gear in the reducer can transport the coolant from the bottom shell to the inside of the reducer by stirring.

Through the topology shown in FIG17 , circulating liquid cooling of the powertrain can be achieved.

FIG18 is a schematic diagram of the cross-sectional structure of the assembly flow channel based on the topological structure shown in FIG17. As shown in FIG18, the power assembly 4 can be an integrated power assembly, and the drive motor 6 and the reducer 8 can be assembled in the same assembly casing. Schematically, the cooling cover 63 and the cooling cover 64 can be combined with the motor casing of the drive motor 6. Since the motor casing of the drive motor 6 also belongs to the assembly casing, it can be considered that the cooling cover 63 and the cooling cover 64 are combined with the assembly casing. FIG18 illustrates the bottom shell 41, the peripheral shell 42, the cooling cover 63 and the cooling cover 64 in the assembly casing, but does not illustrate the reducer casing of the reducer 8.

It is understandable that the power assembly 4 shown in FIG18 is only a schematic diagram and does not limit the actual structure. For example, FIG18 shows the cross-sectional shape of the drive motor 6 and the cross-sectional shape of the reducer 8 on the same plane, but in fact, the cross-sectional shape of the drive motor 6 and the cross-sectional shape of the reducer 8 may not be coplanar.

As shown in FIG. 18 , the motor shaft 69 can be mounted on the assembly housing through a motor bearing 701 fixed on the assembly housing (e.g., the cooling cover 63 and the cooling cover 64). The rotor 71 can surround and be fixed on the outer periphery of the motor shaft 69, and the sealing layer 62, the stator winding 65 and the stator core 61 surround the outer periphery of the rotor 71. The rotor 71, the sealing layer 62, the stator winding 65 and the stator core 61 are located between the cooling cover 63 and the cooling cover 64. One end (e.g., the right end) of the motor shaft 69 can extend out of the cooling cover 64 and be fixedly connected to the input shaft 84 of the reducer 8.

As shown in FIG18 , schematically, the reducer 8 may include an input shaft 84, a gear 85, a gear shaft 88, a gear bearing 87, a gear 86, a gear shaft 81, a gear bearing 83, and a gear 82. The gear 85 may be fixed to the outer periphery of the input shaft 84. The gear shaft 88 may be mounted on the assembly housing via the gear bearing 87, and the gear 86 may be fixed to the outer periphery of the gear shaft 88 and mesh with the gear 85. The gear shaft 81 may be mounted on the assembly housing via the gear bearing 83, and the gear 82 may be fixed to the outer periphery of the gear shaft 81 and mesh with the gear 86. The gear 85, the gear 86, and the gear 82 are all located outside the cooling cover 63 and the cooling cover 64. For example, the above three gears may all be located on the side of the cooling cover 64 facing away from the cooling cover 63.

As shown in FIG18 , a shell flow channel 63f may be provided in the cooling cover 63, and the shell flow channel 63f may be communicated with the motor shaft channel 69a in the motor shaft 69. The motor shaft channel 69a may be communicated with the rotor channel 71a in the rotor 71. The coolant flowing out of the heat exchanger 5 may flow through the shell flow channel 63f, the motor shaft channel 69a and the rotor channel 71a in sequence, thereby taking away the heat of the motor shaft 69 and the rotor 71. The coolant flowing out of the rotor channel 71a may fall into the bottom shell 41. In combination with FIG18 and FIG17 , the shell flow channel 63f may correspond to the flow channel R1 in FIG17 .

As shown in FIG18, a shell flow channel 42a may be provided in the peripheral shell 42, and a shell flow channel 64g may be provided in the cooling cover 64. The shell flow channel 42a, the shell flow channel 64g and the gear shaft flow channel 88a in the gear shaft 88 may be sequentially connected. In combination with FIG18 and FIG17, the shell flow channel 42a and the shell flow channel 64g may also correspond to the flow channel R1 in FIG17.

As shown in FIG18 , a shell flow channel 63g may also be provided in the cooling cover 63, and the shell flow channel 63g, the shell flow channel 42a, the circumferential channel 61d and the axial channel 61b of the stator core 61 (the circumferential channel 61d and the axial channel 61b are both stator cooling channels) may be connected in sequence. The coolant flowing out of the heat exchanger 5 may flow through the shell flow channel 63g, the shell flow channel 42a, the circumferential channel 61d and the axial channel 61b in sequence, and enter the interior of the stator core 61, thereby taking away the heat of the stator core 61 and the stator winding 65. In combination with FIG18 and FIG17 , the shell flow channel 63g and the shell flow channel 42a may correspond to the flow channel R2 in FIG17 .

As shown in FIG18, since the first end flow channel 6a and the second end flow channel 6b are both connected to the axial channel 61b, the coolant entering the axial channel 61b can flow into the first end flow channel 6a to the left and flow into the second end flow channel 6b to the right, that is, the axial channel 61b can split the coolant into the first end flow channel 6a and the second end flow channel 6b. The first end flow channel 6a and the second end flow channel 6b can be filled with coolant so that the stator winding 65 is immersed in the coolant to achieve immersion liquid cooling of the stator winding 65. Combined with FIG18 and FIG17, the flow of the coolant in the axial channel 61b, the first end flow channel 6a and the second end flow channel 6b can correspond to the flow of the coolant along the flow channel R4 in FIG17.

In this embodiment, the second annular wall includes an opening, and the opening is used to communicate with the housing flow passage of the drive motor 6, and the opening faces the axis of the drive motor 6. An example will be given below.

As shown in FIG. 18 , the first end flow channel 6a may have an opening 6c, which may be formed, for example, on the second annular wall 63a of the cooling cover 63 and located at one end radially close to the bottom shell 41. Through the opening 6c, the shell flow channel 63g, the shell flow channel 42a and the first end flow channel 6a may be connected in sequence. The second end flow channel 6b may have an opening 6d, which may be formed, for example, on the second annular wall 64a of the cooling cover 64 and located at one end radially close to the bottom shell 41. Through the opening 6d, the shell flow channel 63g, the shell flow channel 42a and the second end flow channel 6b may be connected in sequence. Therefore, the coolant flowing out of the heat exchanger 5 can flow through the shell flow channel 63g, the shell flow channel 42a and the opening 6c in sequence, and enter the first end flow channel 6a; the coolant flowing out of the heat exchanger 5 can flow through the shell flow channel 63g, the shell flow channel 42a and the opening 6d in sequence, and enter the second end flow channel 6b; the coolant can also flow between the first end flow channel 6a and the second end flow channel 6b through the axial channel 61b. Therefore, the coolant can take away the heat of the stator core 61 and the stator winding 65. Combined with Figures 18 and 17, the shell flow channel 63g and the shell flow channel 42a can correspond to the flow channel R3 in Figure 17.

For example, as shown in FIG. 18 , the first end flow channel 6a may have an opening 6e, which may be formed, for example, on the second annular wall 63a of the cooling hood 63 and located at an end radially away from the bottom shell 41. In the perspective of FIG. 18 , the position of the opening 6e is higher than the opening 6c. The coolant in the first end flow channel 6a may flow out from the opening 6e and fall into the bottom shell 41. The second end flow channel 6b may have an opening 6f, which may be formed, for example, on the second annular wall 64a of the cooling hood 64 and located at an end radially away from the bottom shell 41. In the perspective of FIG. 18 , the position of the opening 6f is higher than the opening 6d.

In this embodiment, by adding a cover body (including a cooling cover 63 and a cooling cover 64) at opposite ends of the stator winding 65, covering the inner circumference of the stator core 61 with a sealing layer 62, sealingly connecting the cover body with the stator core 61 and the sealing layer 62, and constructing an end flow channel (including a first end flow channel 6a and a second end flow channel 6b), the stator winding 65 can be immersed in the end flow channel, and the stator winding 65 is dissipated by using an immersion liquid cooling method, so that the heat of the stator winding 65 can be quickly absorbed and taken away by the coolant, thereby greatly improving the heat dissipation effect of the stator winding 65 and enhancing the temperature uniformity of the cooling of the drive motor 6, which is conducive to improving the output of the rated power of the drive motor 6 and extending the duration of its peak power. For example, in low-temperature and low-flow application scenarios (such as scenarios where the electric drive actively heats up), immersion liquid cooling can prevent the wire of the stator winding 65 from overheating and ensure that the drive motor 6 has good temperature uniformity.

In this embodiment, since the outlet (e.g., opening 6e and opening 6f) of the end flow channel is designed at a higher position, and the inlet (e.g., opening 6c and opening 6d) is designed at a lower position, when the driving pump 9 is stopped and the liquid circuit is stationary and not circulating, the coolant in the end flow channel is not easy to overflow; in addition, when the liquid circuit is stationary and not circulating, due to the characteristics of the driving pump 9, the coolant in the end flow channel will not flow back. The above design can ensure that the end flow channel can always be filled with coolant, ensuring that the stator winding 65 is always immersed in the coolant.

In this embodiment, since the coolant in the end flow channel is not easy to leak into the air gap between the stator and the rotor 71, the wear between the stator and the rotor 71 (such as oil grinding) can be reduced or avoided, thereby reducing the energy consumption of the drive motor 6.

In this embodiment, the sealing layer 62 is designed to prevent the coolant from leaking at the stator core 61 when it flows between the first end flow channel 6a and the second end flow channel 6b through the stator core 61. In other embodiments, the sealing layer 62 may not be provided, and the second annular wall 63a and the first annular wall 63c of the cooling cover 63 are both connected to the stator core 61, and the cooling cover 63 and the stator core 61 form the first end flow channel 6a; similarly, the second annular wall 64a and the first annular wall 64c of the cooling cover 64 are both connected to the stator core 61, and the cooling cover 64 and the stator core 61 form the second end flow channel 6b.

As shown in FIG18 , a shell flow channel 42b may be further provided in the peripheral shell 42, and a shell flow channel 64d, a shell flow channel 64e and a shell flow channel 64f may be further provided in the cooling cover 64. Through the opening 6f of the second end flow channel 6b, the second end flow channel 6b, the shell flow channel 42b and the shell flow channel 64e may be sequentially connected, and the shell flow channel 64d and the shell flow channel 64f may both be connected to the shell flow channel 64e. The shell flow channel 64d may be connected to the accommodating cavity of the motor bearing 702. The shell flow channel 64f may be connected to the gear shaft flow channel 81a in the gear shaft 81. The coolant flowing out of the opening 6f of the second end flow channel 6b may flow through the shell flow channel 42b and the shell flow channel 64d into the accommodating cavity of the motor bearing 702 to dissipate heat from the motor bearing 702. The coolant flowing out of the opening 6f of the second end flow channel 6b can also flow through the shell flow channel 42b, the shell flow channel 64e and the shell flow channel 64f into the gear shaft flow channel 81a to dissipate heat for the gear shaft 81 and the gear bearing 83. That is, the coolant flowing out of the opening 6f of the second end flow channel 6b will be diverted to the motor bearing 702 and the gear shaft flow channel 81a. The coolant can flow in from the opening at the intersection of the shell flow channel 64f and the shell flow channel 64e, and fall into the bottom shell 41 (three curves are used to represent the falling coolant). In combination with Figures 18 and 17, the flow of the coolant in the shell flow channel 42b, the shell flow channel 64d and the motor bearing 702, and the flow of the coolant in the shell flow channel 42b, the shell flow channel 64e, the shell flow channel 64f and the gear shaft flow channel 81a can all correspond to the flow of the coolant along the flow channel R5 in Figure 17.

As shown in FIG. 18 , the coolant can flow out from the gear shaft flow channel 81a and the gear shaft flow channel 88a and fall into the bottom shell 41. The lower part of the gear 86 can be immersed in the coolant in the bottom shell 41. As the gear 86 rotates, all parts of the gear 86 in the circumferential direction can be stained with the coolant, and the gear 86 can also transport the coolant to the gear 85 and the gear 82, so that the gear 86, the gear 85 and the gear 82 can all be cooled.

In some conventional solutions, the heat dissipation of the stator winding is the heat dissipation end point of the entire powertrain. For example, in the solution of using oil injection technology to dissipate heat from the stator winding, after the cooling oil is sprayed on the stator winding, the cooling oil will flow back to the oil pan, waiting for the oil pump to pump the cooling oil back to the beginning of the oil circuit.

Different from the conventional solution, as described above, the coolant in the first end flow channel 6a and the second end flow channel 6b of this embodiment can also enter the other flow channel through the flow channel R5, rather than only falling into the bottom shell 41. Therefore, the first end flow channel 6a and the second end flow channel 6b can be used as the middle section of the assembly flow channel, rather than only being located at the end. The first end flow channel 6a and the second end flow channel 6b, as part of the assembly flow channel, transport coolant to the various components that constitute the other flow channels. This design makes the heat dissipation of the stator winding 65 no longer the end point of the heat dissipation of the entire powertrain 4. After the coolant dissipates heat for the stator winding 65, it can continue to dissipate heat for the various components that constitute the other flow channels. Therefore, this embodiment can realize the recovery and reuse of the coolant. This can allow more coolant to flow through the stator winding 65 at the same time without increasing the flow rate of the drive pump 9, thereby enhancing the heat dissipation of the stator winding 65.

In addition, as shown in FIG. 17 , in this embodiment, due to the design of the first end flow channel 6a and the second end flow channel 6b, the heat of the stator winding 65 can be collected to prevent the heat from being directly dissipated into the atmosphere. The heat can be transported to the thermal management system of the electric vehicle through a heat exchanger, and the thermal management system can use the received heat for heating (for example, heating the power battery and the drive motor) and/or air conditioning (outputting warm air), etc., so as to effectively utilize the heat of the stator winding 65, thereby improving COP and achieving energy saving and cost reduction effects.

For example, in a scenario where the drive motor operates in a low-temperature environment, the heat of the stator winding 65 can be effectively used to shorten the oil preheating time, improve the low-temperature starting performance of the drive motor, reduce energy consumption, and improve COP.

For example, the heat of the stator winding 65 can be effectively utilized to achieve drive motor heating (using the heat of the drive motor to heat the air conditioner or power battery, etc.), and the drive motor is used to replace at least part of the electric heater, which includes but is not limited to a positive temperature coefficient (PTC) heater. In some embodiments, the drive motor can be used to completely replace the electric heater, which can greatly reduce the dependence on the electric heater, reduce costs, reduce energy consumption, and improve COP. In other embodiments, the drive motor heating can be used as a supplement, and the high-voltage electric heater can be replaced with a low-voltage electric heater, which can also have a certain effect of reducing costs, reducing energy consumption, and improving COP.

FIG19 is a schematic diagram of the topological structure of the assembly flow channel of the power assembly 4 in the sixth embodiment of the present application. Comparing FIG19 with FIG20, unlike the fifth embodiment, the topological structure of the sixth embodiment may not have the flow channel R3, that is, the coolant flowing out of the heat exchanger may not flow directly into the cover.

Fig. 20 is a schematic cross-sectional view of the assembly flow channel based on the topological structure shown in Fig. 19. Comparing Fig. 20 with Fig. 18, unlike the fifth embodiment, the end flow channel of the sixth embodiment may not have the opening 6c and the opening 6d.

The solution of the fifth embodiment may have the same or equivalent technical effect as that of the fourth embodiment, which will not be described in detail here.

Different from the fifth or sixth embodiment described above, in other embodiments, the axial channel 61b in the stator core 61 can be eliminated, so that the circumferential channel 61d on the stator core 61 is connected to the wire slot 61a, and a gap for the coolant to flow is formed between the wire in the wire slot 61a and the inner wall of the wire slot 61a. Thus, the coolant can enter the wire slot 61a to dissipate heat for the stator core 61; the wire slot 61a can connect the first end flow channel 6a and the second end flow channel 6b, thereby dissipating heat for the two ends of the stator winding 65. Or in other embodiments, the axial channel 61b and the wire slot 61a can be used simultaneously to connect the first end flow channel 6a and the second end flow channel 6b.

FIG21 is a schematic diagram of the topological architecture of the assembly flow channel of the power assembly 4 in the seventh embodiment of the present application. Comparing FIG21 with FIG19, in the sixth embodiment, the coolant flowing out of the heat exchanger can sequentially pass through the flow channel R2, the stator core and the flow channel R4 to the cooling cover, and the coolant first flows into the stator core and then enters the two cooling covers respectively; however, in the seventh embodiment, the coolant flowing out of the heat exchanger sequentially passes through the flow channel R6, a cooling cover, the flow channel R7, the stator core and the flow channel R8 to another cooling cover (for example, it can be located on the three-phase line side), and the coolant sequentially enters a cooling cover, the stator core and another cooling cover.

FIG22 is a schematic cross-sectional view of the assembly flow channel based on the topological structure shown in FIG21. Comparing FIG22 with FIG20, unlike the sixth embodiment, in the seventh embodiment, the stator core 61 may not have the circumferential channel 61d; the circumferential shell 42 may be provided with a shell flow channel 42c, which may be connected to the first end flow channel 6a through the opening 6e; the cooling cover 63 may not be provided with a shell flow channel 63f, but may be provided with a shell flow channel 63h, one end of the shell flow channel 63h is connected to the shell flow channel 42c, and the other end of the shell flow channel 63h is connected to the motor shaft channel 69a; the second annular wall 64a of the cooling cover 64 may not be provided with an opening 6f.

As shown in FIG22, the driving pump 9, the heat exchanger 5 and the shell flow channel 42a (which can be called the first shell flow channel 42a) are connected in sequence, and the coolant flowing out of the heat exchanger 5 can flow through the shell flow channel 42a and the opening 6d in sequence, and enter the second end flow channel 6b. The shell flow channel 42a and the opening 6d correspond to the flow channel R6 in FIG21. That is, the coolant in the shell flow channel 42a can also flow into the gear shaft flow channel 88a through the shell flow channel 64g, that is, the coolant in the first housing shell flow channel 42a can be diverted to the second end flow channel 6b. That is, the coolant in the first housing shell flow channel 42a can be diverted to the second end flow channel 6b and the gear shaft flow channel 88a.

As shown in FIG22, the coolant in the second end flow channel 6b can enter the axial channel 61b of the stator core 61, and enter the first end flow channel 6a through the axial channel 61b. The axial channel 61b can correspond to the flow channel R7 and the flow channel R8 in FIG21. The coolant in the first end flow channel 6a can enter the housing flow channel 42c, the housing flow channel 42b and the housing flow channel 63h through the opening 6e, and enter the motor shaft channel 69a through the housing flow channel 63h. The housing flow channel 42b and the housing flow channel 63h can correspond to the flow channel R5 in FIG21. In addition, the coolant can also enter the housing flow channel 64d, the housing flow channel 64e and the housing flow channel 64f from the housing flow channel 42b respectively. The housing flow channel 64d, the housing flow channel 64e and the housing flow channel 64f can also correspond to the flow channel R5 in FIG21. That is, the coolant flowing out of the opening 6e can be divided into the motor shaft channel 69a, the rotor channel 71a, the motor bearing 702 and the gear shaft channel 81a. In this embodiment, the housing channel 42c, the housing channel 42b, the housing channel 63h, the housing channel 64d, the housing channel 64e and the housing channel 64f can all be referred to as the second housing channel.

The solution of the seventh embodiment may have the same or equivalent technical effect as that of the sixth embodiment, and will not be described in detail here.

FIG23 is a schematic diagram of the topological structure of the assembly flow channel of the power assembly 4 in the eighth embodiment of the present application. Comparing FIG23 with FIG21, unlike the seventh embodiment, the topological structure of the eighth embodiment may not have the flow channel R1, that is, the coolant flowing out of the heat exchanger may not directly enter the other flow channel.

FIG24 is a schematic cross-sectional structure diagram of the assembly flow channel based on the topological structure shown in FIG23. Comparing FIG24 with FIG22, in Embodiment 7, the shell flow channel 64g connects the shell flow channel 42a and the gear shaft flow channel 88a. Unlike Embodiment 7, in Embodiment 8, the shell flow channel 64g may not be provided, and the shell flow channel 42a (which may be referred to as the first shell flow channel 42a) may be connected to the second end flow channel 6b only through the opening 6d; the shell flow channel 64f may extend downward (i.e., toward the bottom shell 41) and be connected to the gear shaft flow channel 88a, wherein the portion where the shell flow channel 64f overlaps with the motor shaft 69 is blocked by the motor shaft 69.

The solution of the eighth embodiment may have the same or equivalent technical effect as that of the seventh embodiment, and will not be described in detail here.

FIG25 is a schematic diagram of the topological architecture of the assembly flow path of the power assembly 4 in the ninth embodiment of the present application. Comparing FIG25 with FIG23, unlike the eighth embodiment, the position of the heat exchanger in the ninth embodiment on the flow path of the coolant can be adjusted, the coolant flowing out of the drive pump can directly enter a cooling cover along the flow path R6, the coolant flowing out of another cooling cover can enter the heat exchanger along the flow path R9, and the coolant flowing out of the heat exchanger can enter the other flow path along the flow path R10.

In this embodiment, the axial bottom wall includes an opening, the opening is used to connect to the housing flow channel of the drive motor 6, the opening faces the stator core 61, and the distance between the radial opening of the drive motor 6 and the axis of the drive motor 6 is greater than the distance between the first annular wall and the axis. An example will be given below.

FIG26 is a schematic cross-sectional structure diagram of the assembly flow channel based on the topological structure shown in FIG25. Comparing FIG26 with FIG24, unlike the eighth embodiment, the cooling cover 63 of the ninth embodiment can be provided with a shell flow channel 63i, the shell flow channel 63i can be connected to the first end flow channel 6a and the heat exchanger 5, and the shell flow channel 63i can overlap with the shell flow channel 63h but not connected. Among them, the axial bottom wall of the cooling cover 63 can be integrated with the end cover, the shell flow channel 63i can be provided on the axial bottom wall (or provided on the end cover), and the opening of the shell flow channel 63i toward the first end flow channel 6a is the opening 63x on the axial bottom wall, the opening 63x faces the stator core 61, and the opening 63x is connected to the shell flow channel 63i. Along the radial direction of the drive motor 6, the distance between the opening 63x and the axis of the drive motor 6 is greater than the distance between the first annular wall 63c and the axis.

As shown in FIG26 , a shell flow channel 63j may be provided in the cooling cover 63. The shell flow channel 63j may connect the heat exchanger 5 with the shell flow channel 42b. The shell flow channel 63j may also connect with the shell flow channel 63h. The coolant in the first end flow channel 6a may enter the heat exchanger 5 through the shell flow channel 63i. The shell flow channel 63i may correspond to the flow channel R9 in FIG25 . The coolant in the heat exchanger 5 may enter the motor shaft channel 69a along the shell flow channels 63j and the shell flow channels 63h. The coolant in the heat exchanger 5 may also flow along the shell flow channels 63j and the shell flow channels 42b, and enter the shell flow channels 64d and the shell flow channels 64f from the shell flow channels 42b. The shell flow channels 63j and the shell flow channels 63h may correspond to the flow channels R10 in FIG25 . The shell flow channels 63j, the shell flow channels 42b, the shell flow channels 64d and the shell flow channels 64f may also correspond to the flow channels R10 in FIG25 .

The solution of the ninth embodiment may have the same or equivalent technical effect as that of the eighth embodiment, and will not be described in detail here.

In the assembly flow channels of the above-mentioned embodiments 5, 7 and 8, when the flow rate of the driving pump 9 is the same, the amount of coolant passing through the cover body can be increased successively. Among them, since the second end flow channel 6b and the first end flow channel 6a in the embodiment 7 are in series relationship, the temperature of the winding end 65b of the stator winding 65 located in the second end flow channel 6b is inconsistent with the temperature of the winding end 65a of the stator winding 65 located in the first end flow channel 6a. Since in the embodiment 8, the second end flow channel 6b, the stator cooling channel, the first end flow channel 6a and the other flow channels are connected in series successively, the coolant flowing out of the heat exchanger 5 will not be diverted, so the amount of coolant in the second end flow channel 6b and the first end flow channel 6a is large, so the heat dissipation of the winding end 65b and the winding end 65a is better. In order to realize the design of "sequential series connection", the three-phase line interface can be well sealed.

Different from the above-mentioned embodiment 7, embodiment 8 or embodiment 9, in other embodiments, the axial channel 61b in the stator core 61 can be eliminated, and a gap for the coolant to flow is formed between the wire in the wire slot 61a and the inner wall of the wire slot 61a. Thus, the coolant can enter the wire slot 61a to achieve heat dissipation of the stator core 61; the wire slot 61a can connect the first end flow channel 6a and the second end flow channel 6b, thereby achieving heat dissipation of the two ends of the stator winding 65. Or in other embodiments, the axial channel 61b and the wire slot 61a can be used simultaneously to connect the first end flow channel 6a and the second end flow channel 6b.

The above embodiment takes the cover body and the motor housing as an example of being integrated as one. It is understandable that this is only an example. In other embodiments, at least a portion of the cover body can be independent of the motor housing. The opening on the cover body and the corresponding housing flow channel can be designed to obtain an assembly flow channel that meets product requirements.

In any of the above embodiments, any inlet and any outlet of each shell flow channel, and any inlet and any outlet of each end flow channel can be designed in position according to product requirements, and are not limited to those shown in the drawings.

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

Claims (15)

A drive motor with immersion cooling of stator winding ends, characterized in that the drive motor comprises: A stator core and a stator winding, wherein the stator core is used to fix the stator winding, one winding end of the stator winding is exposed at one end of the stator core along the axial direction of the drive motor, and the inner diameter of the one winding end of the stator winding along the radial direction of the drive motor is larger than the inner diameter of the stator core; A cooling hood, the cooling hood is used to contain coolant and the one winding end, the cooling hood includes a first annular wall, the outer diameter of the first annular wall along the radial direction of the drive motor is less than or equal to the inner diameter of the one winding end of the stator winding, the first annular wall is used to enclose the one end of the stator core along the axial direction of the drive motor toward the stator core to form a containing structure, and the coolant contained in the containing structure is used for immersion cooling of the one winding end. The drive motor according to claim 1, characterized in that the cooling cover comprises a second annular wall, and the inner diameter of the second annular wall in the radial direction of the drive motor is larger than the outer diameter of the first annular wall and the outer diameter of the one winding end. The drive motor according to claim 1 or 2, characterized in that the drive motor comprises: A stator housing, the stator housing being used to fix the stator core, the length of the stator housing along the axial direction of the drive motor being greater than the stator core, and the outer diameter of the stator core along the radial direction of the drive motor being less than or equal to the inner diameter of the stator housing; An end cover is used for fixedly connecting the stator housing, and an end surface of the end cover is arranged opposite to the end surface of the one end of the stator core along the axial direction of the drive motor. The drive motor according to claim 3, characterized in that the inner circumferential surface of the stator housing is used to fix the first annular wall. The drive motor according to claim 4, characterized in that the inner circumferential surface of the stator housing is used to fix the second annular wall or serve as the second annular wall. The drive motor according to claim 3, characterized in that the one end surface of the end cover is used for: Fixing the other end of the first annular wall away from the stator core along the axial direction of the drive motor; or, Fixing the other end of the second annular wall away from the stator core along the axial direction of the drive motor; or, The other end of the first annular wall away from the stator core along the axial direction of the drive motor is fixed, and the other end of the second annular wall away from the stator core along the axial direction of the drive motor is fixed. The drive motor according to claim 3 is characterized in that the cooling cover comprises an axial bottom wall, and the axial bottom wall, the one winding end and the end surface of the one end of the stator core are arranged in sequence along the axial direction of the drive motor. The drive motor according to claim 7, characterized in that the one end surface of the end cover is used as the axial bottom wall of the cooling hood. The drive motor according to claim 7 is characterized in that the outer peripheral surface of the axial bottom wall is used to fix the second annular wall, and the end surface of the axial bottom wall facing the stator core is used to fix the first annular wall of the cooling cover. The drive motor according to claim 7, characterized in that the end surface of the axial bottom wall facing the stator core is used for fixedly connecting the second annular wall of the cooling cover. The drive motor according to claim 2, characterized in that the drive motor comprises a plurality of stator cooling channels, the stator cooling channels comprise a plurality of coolant outlets, wherein: The plurality of coolant outlets are spaced apart on the end surface of the one end of the stator core along the circumferential direction of the drive motor, and the distance between each coolant outlet and the axis of the drive motor along the radial direction of the drive motor is greater than the outer diameter of the one winding end; An outer diameter of the second annular wall in the radial direction of the drive motor is greater than a distance between at least part of the coolant outlet and an axis of the drive motor. The drive motor according to claim 2, characterized in that the second annular wall comprises an opening, the opening is used to connect to the housing flow channel of the drive motor, and the opening faces the axis of the drive motor. The drive motor according to any one of claims 7 to 10 is characterized in that the axial bottom wall includes an opening, the opening is used to connect to the shell flow channel of the drive motor, the opening faces the stator core, and the distance between the opening and the axis of the drive motor along the radial direction of the drive motor is greater than the distance between the first annular wall and the axis. A power assembly, characterized in that the power assembly comprises a reducer and a drive motor as described in any one of claims 1 to 13, and the input shaft of the reducer is used for transmission connection to the motor shaft of the drive motor. An electric vehicle, characterized in that the electric vehicle comprises a frame and the power assembly according to claim 14, and the frame is used to fix the power assembly.