Motor cooling system, motor, electric drive assembly system and vehicle

Abstract

The invention relates to a motor cooling system which is characterized in that the motor cooling system comprises a shell (10) and a stator (20), the shell (10) comprises a water cooling channel (11) arranged on the shell (10), the water cooling channel (11) is arranged to enable cooling water to circulate in the water cooling channel (11), and the stator (20) is contained in the shell (10). A first channel (21) used for allowing oil to pass through is arranged between the stator (20) and the shell (10), and the first channel (21) is arranged to enable heat exchange between the cooling water and the oil. The present disclosure also relates to an electric machine comprising such an electric machine cooling system, an electric drive assembly system comprising such an electric machine, and a vehicle comprising such an electric drive assembly system.

Description

Technical Field

[0001] The present disclosure relates to a motor cooling system. In particular, a motor cooling system according to the present disclosure provides a channel for heat exchange between cooling water and oil of the motor between a housing and a stator of the motor. The present disclosure also relates to a motor including such a motor cooling system, an electric drive assembly system including such a motor, and a vehicle including such an electric drive assembly system. Background Art

[0002] Motors for driving vehicles generally have a relatively large power and generate a large amount of heat during continuous operation. If the heat dissipation is insufficient, the generated heat will accumulate inside the motor, causing the motor temperature to rise and affecting the reliability and performance of the motor.

[0003] According to different cooling media, existing motors include water-cooled motors or oil-cooled motors. A water-cooled motor cools the motor through a water-cooling circuit in which cooling water circulates. The water-cooling circuit generally includes a surrounding pipe arranged in the housing of the motor, so that it can have a better cooling effect on the radially outer part of the motor (for example, the iron core part of the motor stator). An oil-cooled motor cools the motor through an oil-cooling circuit in which oil circulates. The oil-cooling circuit can directly guide the oil into the interior of the motor housing and directly contact the internal components of the motor, so that it can have a better cooling effect on the internal components of the motor (for example, the windings of the stator). It is also known that the cooling arrangement of the motor includes both a water-cooling circuit and an oil-cooling circuit, so that the advantages of both water-cooled motors and oil-cooled motors can be combined to effectively cool each part of the motor. However, such a motor cooling system needs to include two radiators to dissipate heat from the cooling water circulating in the water-cooling circuit and the oil circulating in the oil-cooling circuit respectively. This increases the component cost of the motor cooling system and the difficulty of installing the motor in the vehicle body.

[0004] Therefore, there is a need for a motor cooling system that can fully cool each part of the motor using both cooling water and oil without increasing the number of radiators. Summary of the Invention

[0005] Therefore, the present disclosure aims to solve the above problems, and its purpose is to provide a novel motor cooling system, motor, electric drive assembly system, and vehicle. The motor cooling system according to the present disclosure can fully cool each part of the motor using both cooling water and oil without increasing the number of radiators, thereby reducing the component cost of the motor cooling system and making it easy to install the motor in the vehicle body.

[0006] The above object is achieved by a motor cooling system according to an embodiment of the present disclosure, which includes: a housing including a water cooling channel provided thereon, the water cooling channel being configured such that cooling water circulates in the water cooling channel; and a stator accommodated in the housing. A first channel for oil passage is provided between the stator and the housing, and the first channel is configured such that heat exchange occurs between the cooling water and the oil.

[0007] One object of the present disclosure is to provide a motor cooling system that can sufficiently cool various parts of the motor using cooling water and oil without increasing the number of radiators. The motor cooling system according to the present disclosure is provided with a water cooling channel on the housing, and the cooling water circulating in the water cooling channel can be used to cool the radially outer part of the motor close to the housing. The motor cooling system also provides a first channel between the stator accommodated in the housing and the housing, and oil flows in the first channel, enabling the stator to be cooled within the housing. In particular, the first channel is configured such that heat exchange can occur between the cooling water and the oil. Thus, the motor cooling system according to the present disclosure only needs to provide a radiator for the cooling water on the water cooling circuit, and there is no need to provide a radiator for the oil. Instead, the oil is cooled by the cooling water. In this way, the motor cooling system only needs to provide one radiator, thereby reducing the number of radiators and lowering the component cost.

[0008] The motor cooling system according to the present disclosure may also have one or more of the following features individually or in combination.

[0009] According to an embodiment of the present disclosure, the first channel is formed by an outer groove provided on the outer surface of the stator. According to this technical feature, oil flows in the outer groove on the outer surface of the stator, close to the water cooling channel on the housing, facilitating heat exchange between the oil and the cooling water.

[0010] According to an embodiment of the present disclosure, the stator is provided with an annular receiving groove on its outer circumference for receiving oil supplied from an oil pump. Accordingly, the receiving groove constitutes a part of the oil circulation path of the motor cooling system.

[0011] According to an embodiment of the present disclosure, the first channels are circumferentially spaced apart and in fluid communication with the receiving groove. That is, the oil received by the receiving groove can flow into the first channel to exchange heat with the cooling water.

[0012] According to an embodiment of the present disclosure, the stator is further provided with a second channel for delivering the oil from the receiving groove to both ends of the stator. The cooling oil delivered to both ends of the stator through the second channel can cool the ends of the stator windings.

[0013] According to an embodiment of the present disclosure, the stator includes two first stacked section segments arranged axially and a second stacked section segment disposed between the two first stacked section segments.

[0014] According to an embodiment of the present disclosure, the receiving groove is provided on the second stacked section segment.

[0015] According to an embodiment of the present disclosure, at least a part of the first channel and the second channel is provided on the first stacked section segment.

[0016] According to an embodiment of the present disclosure, the stator further includes a transition stacked section segment disposed between each of the two first stacked section segments and the second stacked section segment, and at least a part of the first channel and the second channel is provided on the transition stacked section segment.

[0017] According to an embodiment of the present disclosure, the stator further includes an end stacked section segment disposed on an axially opposite side of each of the two first stacked section segments and the second stacked section segment, and at least a part of the first channel and the second channel is provided on the end stacked section segment.

[0018] According to an embodiment of the present disclosure, the first channel is formed by an inner groove provided on the inner surface of the housing. According to this technical feature, oil flows in the inner groove on the inner surface of the housing, close to the water cooling channel on the housing, facilitating heat exchange between the oil and the cooling water.

[0019] The present disclosure also relates to an electric motor including the motor cooling system as described above.

[0020] The present disclosure also relates to an electric drive assembly system including the electric motor as described above.

[0021] The present disclosure also relates to a vehicle including the electric drive assembly system as described above. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The above and other features and advantages of the present disclosure will become more apparent from the following detailed description of exemplary embodiments in conjunction with the accompanying drawings, and the description and drawings are for exemplary purposes only and do not limit the scope of the present disclosure in any way. The following drawings are not deliberately drawn to scale in actual size, and the emphasis is on showing the gist of the present disclosure.

[0023] Figure 1 An electric motor in an assembled state is shown, which includes the motor cooling system according to an embodiment of the present disclosure.

[0024] Figure 2 is Figure 1 an exploded view of the shown electric motor.

[0025] Figure 3 Shows the housing of the electric machine.

[0026] Figure 4 Shows the stator of the electric machine.

[0027] Figure 5 Is a partial cross-sectional view of the stator.

[0028] Figure 6 Shows the laminations in the second lamination segment of the stator.

[0029] Figure 7A Shows the laminations in the transition lamination segment of the stator, Figure 7B Is a detailed view of a part of the lamination.

[0030] Figure 8A Shows the laminations in the first lamination segment of the stator, Figure 8B Is a detailed view of a part of the lamination.

[0031] Figure 9A Shows the laminations in the end segment of the stator, Figure 9B Is a detailed view of a part of the lamination. Detailed Description

[0032] In order to make the objectives, technical solutions and advantages of the embodiments of the present disclosure clearer, the technical solutions of the embodiments of the present disclosure will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present disclosure.

[0033] Unless otherwise defined, the technical terms or scientific terms used herein shall have the ordinary meanings as understood by those of ordinary skill in the art to which the present disclosure pertains. The terms "a", "an", or "the" and similar words used in the specification and claims of the present patent application do not denote a limitation of quantity, but rather denote the presence of at least one. Words such as "comprising" or "including" and similar words mean that the elements or items appearing before the word cover the elements or items listed after the word and their equivalents. "Connection" or "coupling" and similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Upper", "lower", "left", "right", etc. are only used to indicate relative positional relationships, and when the absolute position of the object being described changes, the relative positional relationship may also change accordingly. The terms "axial" and "axial direction" refer to the direction of the rotation axis X of the electric machine.

[0034] For ease of description, the accompanying drawings of the present disclosure correspondingly simplify or omit commonly used components in the art, such as other components unrelated to the description of the present disclosure, such as external connection wires. These omitted or simplified components do not affect those skilled in the art's understanding of the content of the present disclosure.

[0035] Figure 1 FIG. 3 shows the motor 100 in an assembled state according to an exemplary embodiment of the present disclosure. Figure 2 FIG. 4 shows an exploded view of the motor 100. As shown, the motor 100 includes a housing 10 and a stator 20 received within the housing 10. Referring Figure 4 to FIG. 5, the stator 20 includes a winding 201 and a core portion 202. The winding 201 extends axially in the winding slots 204 of the core portion 202 and has winding ends 203 that extend beyond the core portion 202.

[0036] The core portion 202 of the stator 20 is composed of a plurality of laminations stacked together. These laminations can be divided into a plurality of lamination segments. Figure 5 FIG. 6 shows a cross-sectional view of an axial half of the core portion 202 of the stator 20. In Figure 5 FIG. 6, the core portion 202 includes an end lamination segment 28, a first lamination segment 25, a transition lamination segment 27, and a second lamination segment 26 in the axial direction. It can be understood that the core portion 202 also includes a transition lamination segment 27, a first lamination segment 25, and an end lamination segment 28 on the other axial side of the second lamination segment 26. Each lamination segment of the stator 20 is provided with winding slots 204 located radially inward and lugs 205 protruding radially outward. The winding slots 204 are used to hold and separate the windings 201 of the stator 20. The lugs 205 cooperate with the positioning slots 101 on the inner surface of the housing 10 to circumferentially position the core portion 202 of the stator 20. In addition to the above-mentioned lugs 205 and winding slots 204, as will be described in detail below, the laminations of each lamination segment of the stator 20 have the same structure, while the structures of the laminations between different lamination segments can be different.

[0037] Exemplarily, the motor 100 can be a drive motor for driving a vehicle. A relatively large alternating current flows through the winding 201 of the drive motor to generate an alternating magnetic field for causing a rotor (not shown in the drawings) of the drive motor to rotate about the rotation axis X of the motor. The core portion 202 bears the alternating magnetic field and generates hysteresis loss and eddy current loss. Therefore, the winding 201 and the core portion 202 of the stator 20 are the main heat-generating components of the motor 100 and need to be cooled. To this end, the motor 100 is provided with a motor cooling system that can cool the winding 201 and the core portion 202 of the stator 20.

[0038] Specifically, the motor cooling system includes a water-cooling channel 11 arranged on the housing 10. Referring Figures 1 to 3, the housing 10 includes a cylindrical intermediate tube 12, two end caps 13 respectively located on both sides of the intermediate tube 12, and two gaskets 14 axially arranged between the intermediate tube 12 and the two end caps 13. Two ports 15a and 15b of the water cooling channel 11 are provided on the outer surface of the intermediate tube 12. The water cooling channel 11 axially penetrates the intermediate tube 12 and the gaskets 14, and makes a U-shaped turn at the end caps 13. Cooling water flows in from one of the two ports 15a and 15b, flows through the U-shaped water cooling channel 11 throughout the housing 10, and flows out from the other of the two ports 15a and 15b. The heat taken away by the cooling water from the motor 100 is dissipated in a cooling water radiator (not shown in the drawings) of the motor cooling system.

[0039] The above-mentioned water cooling channel 11 is adapted to cool the external part of the motor 100, such as the core part 202 of the stator 20. In addition, the motor cooling system can also cool the internal part of the motor 100 through cooling oil, such as cooling the winding 201 of the stator 20 through cooling oil.

[0040] For this purpose, the motor cooling system includes an oil pump 31, an oil delivery pipe 32, a channel inside the housing 10, and an oil collector 33. The cooling oil circulating in the motor cooling system can be pumped by the oil pump 31 from the oil collector 33 through the oil delivery pipe 32 into the housing 10 of the motor 100, flows through the channel inside the housing 10 to cool the internal components of the motor (especially the winding 201 of the stator 20), then converges at the bottom of the housing 10, and flows back into the oil collector 33 that is in fluid communication with the housing 10 again.

[0041] Specifically, the oil delivery pipe 32 passes through the housing 10 and leads to an annular receiving groove 23 located at the axial middle part of the stator 20. The receiving groove 23 is formed by a second laminated section 26. Refer to Figure 4 and Figure 5 , the outer diameter of the second laminated section 26 is smaller than the outer diameter of the transition laminated section 27, so that an annular receiving groove 23 is formed under the clamping of the two transition laminated sections 27. Accordingly, the stator 20 receives the oil pumped by the oil pump 31 through the oil delivery pipe 32 through the receiving groove 23, and these oils can then be used to cool the stator 20.

[0042] After being received by the receiving groove 23, the oil has different flow paths on the stator 20. As Figure 5As shown, a first channel 21 is provided on the outer surface of the stator 20 and is in fluid communication with the receiving groove 23. Thus, the oil received by the receiving groove 23 can flow through the first channel 21 and the oil can be transported to the end of the stator 20. Optionally, the first channel 21 is formed by an outer groove 22 on the outer surface of the stator 20, so as to be close to the inner surface of the housing 10. Thus, the oil flowing in the first channel 21 can exchange heat with the cooling water circulating in the water-cooling channel 11 on the housing 10 and is cooled by the cooling water. That is to say, in the motor cooling system according to the present disclosure, the heat generated by the motor 100 absorbed by the oil can be taken away by the cooling water. Therefore, there is no need to provide a dedicated radiator in the oil circulation path of the motor cooling system.

[0043] Reference Figure 5 , Figures 7A - 9B , the outer groove 22 forming the first channel 21 is provided at intervals in the circumferential direction on the transition lamination section 27, the first lamination section 25 and the end lamination section 28 of the iron core part 202 of the housing 20, that is, the outer groove 22 is provided on the lamination sections except the second lamination section 26 forming the receiving groove 23. Thus, the first channel 21 communicates the receiving groove 23 and the end of the housing 20. After flowing through the first channel 21, the oil collects at the bottom of the housing 10 and flows into the oil collector 33, so that it can be pumped by the oil pump 31 and continue to circulate in the motor cooling system.

[0044] In addition to the first channel 21, a second channel 24 is also provided in the stator 20 and is in fluid communication with the receiving groove 23 to transport the oil from the receiving groove 23 to both ends of the stator 20. As Figure 5 shown, the second channel 24 is relatively close to the radial inner part of the iron core part 202 of the housing 20, that is, close to the winding groove 204 of the iron core part 202. Similar to the outer groove 22, the second channel 24 is also provided on the lamination sections except the second lamination section 26 forming the receiving groove 23.

[0045] Reference Figure 7A and Figure 7B, the laminations in the transition lamination section 27 are provided with transition holes 241 and 242, and these transition holes 241 and 242 form a part of the second channel 24 in the transition lamination section 27. In particular, the radially outer part of the transition hole 241 includes an arc section 241a, an intermediate section 241b, and an oval inner section 241c, and its circumferential position corresponds to the lug 205. The lug 205 of the second lamination section 26 forming the receiving groove 23 obstructs the circumferential flow of oil in the receiving groove 23. When obstructed by the lug 205, the oil can flow into the arc section 241a, bypass the lug 205, and then flow back into the receiving groove 23. The transition hole 242 consists of an oval outer section 242a and an oval inner section 242b. The outer section 242a of the transition hole 242 communicates with the receiving groove 23 through its radially outer part, enabling the oil to flow into this transition hole 242. The inner section 241c of the transition hole 241 and the inner section 242b of the transition hole 242, especially their radially inner parts, are close to the winding groove 204, so as to cool the winding 201 in the winding groove 204.

[0046] Reference Figure 8A and Figure 8B , the laminations in the first lamination section 25 are provided with oval lamination holes 243. These lamination holes 243 are axially aligned with the inner sections 241c / 242b of the transition holes 241 / 242, forming a part of the second channel 24 in the first lamination section 25. The oil can flow from the transition holes 241 / 242 into the lamination holes 243 and cool the winding 201 in the winding groove 204.

[0047] Reference Figure 9A and Figure 9B , the laminations in the end lamination section 28 are provided with circular end holes 244. These end holes 244 are axially aligned with the radially inner part of the lamination holes 243, forming a part of the second channel 24 in the end lamination section 28. The oil flowing in the lamination holes 243 can be sprayed from the second channel 24 to the winding end 203 of the winding 201 through this end hole 244 to cool the winding end 203. The area of the end hole 244 is relatively greatly reduced compared to the lamination hole 243, which is beneficial to increasing the flow rate of the oil sprayed out from the end hole 244 and increasing the proportion of the oil sprayed onto the winding end 203.

[0048] After being sprayed onto the winding end 203 and cooling it, the oil collects at the bottom of the housing 10 and flows into the oil collector 33. In the bottom of the housing 10 and the oil collector 33, the oil flowing through the first channel 21 and the oil flowing through the second channel 24 are fully mixed. Although only a part of the oil exchanges heat with the cooling water in the water-cooling channel 11 in the first channel 21, all the oil circulating in the motor cooling system can thus have its temperature reduced for cooling the part of the motor 100 inside the housing 10. Therefore, the oil in the motor cooling system can dissipate heat through the radiator of the water-cooling part without setting a radiator in the oil circulation path.

[0049] The present disclosure has been described above with respect to an embodiment in which the first channel 21 is formed by the outer groove 22 provided on the outer surface of the stator 20. It can be understood that the first channel 21 can also be formed by an inner groove provided on the inner surface of the housing 10. The inner groove is in fluid communication with the receiving groove 23 on the stator 20, so that the oil can flow through the inner groove and exchange heat with the cooling water in the water-cooling channel 11. In a further alternative embodiment, the first channel 21 can also be jointly formed by the outer groove 22 on the outer surface of the stator 20 and the inner groove on the inner surface of the housing 10.

[0050] According to another aspect of the present disclosure, a motor is provided, which includes the motor cooling system as described above.

[0051] According to another aspect of the present disclosure, an electric drive assembly system is provided, which includes the motor as described above.

[0052] According to another aspect of the present disclosure, a vehicle is provided, which includes the electric drive assembly system as described above. The vehicle can be an electrified vehicle, such as a battery electric vehicle (BEV), a hybrid electric vehicle (HEV), a plug-in hybrid electric vehicle (PHEV), a range extended electric vehicle, a fuel cell electric vehicle (FCEV). The vehicle can also be a hydrogen energy vehicle.

[0053] Certain features, structures or characteristics in one or more embodiments of the present disclosure can be appropriately combined.

[0054] The foregoing is a description of the present disclosure and should not be construed as limiting thereof. Although several exemplary embodiments of the present disclosure have been described, those skilled in the art will readily appreciate that many modifications can be made to the exemplary embodiments without departing from the novel teachings and advantages of the present disclosure. Accordingly, all such modifications are intended to be included within the scope of the present disclosure as defined by the claims. It should be understood that the foregoing is a description of the present disclosure and that the present disclosure should not be considered limited to the specific embodiments disclosed, and modifications to the disclosed embodiments as well as other embodiments are intended to be included within the scope of the present disclosure.

Claims

1. A motor cooling system, characterized in that, The motor cooling system includes: A housing (10) including a water cooling channel (11) provided thereon, and the water cooling channel (11) is arranged such that cooling water circulates in the water cooling channel (11). A stator (20) accommodated in the housing (10). Wherein, a first channel (21) for oil passage is provided between the stator (20) and the housing (10), and the first channel (21) is arranged such that heat exchange occurs between the cooling water and the oil.

2. The motor cooling system according to claim 1, characterized in that, The first channel (21) is formed by an outer groove (22) provided on the outer surface of the stator (20).

3. The motor cooling system according to claim 1 or 2, characterized in that, The stator (20) is provided with an annular receiving groove (23) on its outer circumference for receiving oil supplied from an oil pump (31).

4. The motor cooling system according to claim 3, characterized in that, The first channels (21) are circumferentially spaced apart and in fluid communication with the receiving groove (23).

5. The motor cooling system according to claim 3, characterized in that, The stator (20) is further provided with a second channel (24) for transporting the oil from the receiving groove (23) to both ends of the stator (20).

6. The motor cooling system according to claim 5, characterized in that, The stator (20) includes two first stacked segment portions (25) arranged axially and a second stacked segment portion (26) disposed between the two first stacked segment portions (25).

7. The motor cooling system according to claim 6, characterized in that, The receiving groove (23) is provided on the second stacked segment portion (26).

8. The motor cooling system according to claim 6 or 7, characterized in that, At least a part of the first channel (21) and the second channel (24) is provided on the first stacked segment portion (25).

9. The motor cooling system according to claim 6 or 7, characterized in that, The stator (20) further includes a transition stacked segment portion (27) disposed between each of the two first stacked segment portions (25) and the second stacked segment portion (26), and at least a part of the first channel (21) and the second channel (24) is provided on the transition stacked segment portion (27).

10. The motor cooling system according to claim 6 or 7, characterized in that, The stator (20) further includes an end stacked segment portion (28) disposed on a side of each of the two first stacked segment portions (25) opposite to the second stacked segment portion (26) in the axial direction, and at least a part of the first channel (21) and the second channel (24) is provided on the end stacked segment portion (28).

11. The motor cooling system according to claim 1, characterized in that, The first channel (21) is formed by an inner groove provided on the inner surface of the housing (10).

12. A motor (100), comprising the motor cooling system according to any one of claims 1 to 11.

13. An electric drive assembly system, comprising the motor (100) according to claim 12.

14. A vehicle, comprising the electric drive assembly system according to claim 13.

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