Liquid cooling structure, motor with liquid cooling structure and cooling system

Abstract

The present disclosure provides a liquid cooling structure, at least partially disposed within a motor, comprising: a first outlet configured to allow a cooling liquid to flow out of the motor; the switching mechanism is matched with the first outlet; the driving mechanism is configured to be used for driving the switching mechanism to move based on the mode where the electric driving system is located, and the driving mechanism comprises the steps that in response to the situation that the electric driving system is in the driving mode, the switching mechanism is driven to move so that the first outlet can be opened; and in response to the electric drive system being in the charging mode, driving the switching mechanism to move to at least partially block the first outlet. According to the liquid cooling structure disclosed by the invention, dynamic switching of the cooling liquid can be realized in the driving mode and the charging mode, and differential heat dissipation requirements in the driving mode and the charging mode are balanced in a low-cost, high-reliability and / or miniaturized structural design mode.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to the field of electric machines, and in particular to a liquid cooling structure, an electric machine with the liquid cooling structure, and a cooling system. BACKGROUND

[0002] With the rapid development of new energy vehicle technology, efficient heat dissipation of electric drive systems has become one of the key challenges to improve the performance and reliability of electric machines. Among the cooling methods such as natural cooling, air cooling and liquid cooling, liquid cooling is the most efficient, and is therefore usually used for efficient heat dissipation. Since oil has the characteristics of high thermal conductivity and non-conductivity, it is usually used as the medium for liquid cooling.

[0003] The electric drive system of a new energy vehicle usually has a driving mode and a charging mode. The electric machine of some existing electric drive systems only has a heat dissipation requirement in the driving mode, and has no electric machine cooling requirement in the charging mode because the charging current does not pass through the electric machine of the electric drive system.

[0004] In fact, the electric machine has significantly different cooling requirements in the two modes, and the traditional single liquid cooling solution cannot meet the above two modes, leading to an increasingly prominent contradiction between heat dissipation efficiency and system performance.

[0005] In the driving mode, the electric machine is in a high-speed operation state. If large liquid immersion cooling is used, for example, the stator and rotor are mostly or completely immersed, although the heat dissipation effect can be enhanced, the motion resistance of the rotating parts will be significantly increased, reducing the efficiency and output performance of the electric machine. In contrast, in the charging mode, for example, especially for high-power alternating current charging, the electric machine is stationary, but the stator winding generates a large amount of heat due to the large current passing through, causing the winding copper temperature to rise too quickly, even exceeding the safety threshold, affecting the system life and charging efficiency.

[0006] To solve this problem, the traditional solution usually uses a multi-liquid path independent cooling system to meet the cooling requirements of different modes by adding additional pump bodies, valve bodies and complex pipe layout. However, this design not only significantly increases the cost and processing difficulty of parts, but also introduces higher leakage risk due to the increase in sealing points, reducing system reliability. In addition, the complex liquid path structure also occupies more space, which is not conducive to the miniaturization and integration design of the electric drive system.

[0007] Therefore, there is an urgent need for a new liquid cooling structure. SUMMARY

[0008] To overcome the above and / or other problems, some embodiments of the present disclosure provide a liquid cooling structure disposed at least partially within an electric machine, the liquid cooling structure comprising: a first outlet configured to allow a cooling liquid to flow out of the electric machine; a switching mechanism matched with the first outlet; and a driving mechanism configured to drive movement of the switching mechanism based on a mode in which the electric drive system is in, including: in response to the electric drive system being in a driving mode, driving the switching mechanism to move to open the first outlet; and in response to the electric drive system being in a charging mode, driving the switching mechanism to move to at least partially block the first outlet.

[0009] In some embodiments, the switching mechanism in the liquid cooling structure comprises a blocking portion and a driving portion, wherein the blocking portion is configured to at least partially block the first outlet, and the driving portion is coupled with the driving mechanism to move the blocking portion.

[0010] In some embodiments, the liquid cooling structure, the radial dimension of the blocking portion matches the size of the first outlet, so that the blocking portion can be inserted into the first outlet.

[0011] In some embodiments, the liquid cooling structure, the side wall of the first outlet has a plurality of first openings spaced apart, the surface of the blocking portion has a plurality of second openings matched with the plurality of first openings and a third opening in communication with the cavity of the electric machine, and the blocking portion is configured to: by the second openings being misaligned with the first openings, to block the first outlet; and by the second openings being aligned with the first openings, to open the first outlet.

[0012] In some embodiments, the liquid cooling structure, the radial dimension of the blocking portion is greater than the size of the first outlet, so as to cover the first outlet.

[0013] In some embodiments, the liquid cooling structure, the first outlet is disposed at the bottom of the cavity of the electric machine.

[0014] In some embodiments, the liquid cooling structure further comprises: a second outlet disposed within the electric machine and higher than the position of the rotor in the electric machine in the direction of gravity.

[0015] In some embodiments, the liquid cooling structure further comprises: a baffle ring configured to hinder the cooling liquid from flowing to the second outlet when the electric drive system is in a driving mode, and to extend the flow path of the cooling liquid in the electric machine when the electric drive system is in a charging mode.

[0016] In some embodiments, the liquid cooling structure further comprises a total outlet, which is in communication with the first outlet and the second outlet.

[0017] In some embodiments, the liquid cooling structure further comprises an inlet, which is configured to allow the cooling liquid to flow from the inlet into the cavity of the motor.

[0018] The present disclosure also provides a motor configured to work in a driving mode and a charging mode of an electric drive system, the motor comprising: a stator having a plurality of stator teeth and a plurality of stator windings wound on the plurality of stator teeth, wherein in the charging mode, a charging current flows through at least a portion of the stator windings; a rotor comprising a rotor core and a magnetic steel, or comprising a rotor core and windings on the rotor core; and a liquid cooling structure according to any one of the embodiments of the present disclosure.

[0019] The present disclosure also provides a cooling system comprising: a reservoir in communication with the motor and configured to store the cooling liquid flowing out of the motor; a pump in communication with the reservoir and configured to draw the cooling liquid from the reservoir; and a cooler in communication with the pump and the motor and configured to cool the cooling liquid drawn by the pump and deliver the cooled cooling liquid to the motor.

[0020] In some embodiments, the reservoir of the cooling system is integrated with the motor.

[0021] The liquid cooling structure according to the present disclosure can dynamically switch the cooling liquid in both the driving mode and the charging mode, and balance the differentiated heat dissipation requirements in the driving mode and the charging mode in a low-cost, high-reliability and / or small-size structure design manner. BRIEF DESCRIPTION OF DRAWINGS

[0022] The accompanying drawings are included to provide a further understanding of the present disclosure and constitute a part of the specification, illustrate the embodiments of the present disclosure and are used to explain the present disclosure together with the embodiments of the present disclosure, but do not constitute a limitation on the present disclosure.

[0023] In the drawings, the main connection relationship or relative position relationship of various components is shown, rather than all these relationships, and the components and connections in the drawings are not necessarily drawn according to the actual proportions. In the drawings:

[0024] Figure 1 is a structural cross-sectional view of an exemplary motor comprising a liquid cooling structure according to some embodiments of the present disclosure.

[0025] Figure 2 is a brief structural cross-sectional view of a switching mechanism in a liquid cooling structure according to a first embodiment of the present disclosure, which is implemented as a plug structure and in an open state.

[0026] Figure 3 This is a simplified structural cross-sectional view of the liquid cooling structure according to the first embodiment of the present disclosure, in which the switching mechanism is implemented as a plug structure and in a blocked state.

[0027] Figure 4 This is a simplified structural cross-sectional view of the switching mechanism in the liquid cooling structure according to the second embodiment of the present disclosure, which is implemented as an open structure and in the open state.

[0028] Figure 5 This is a simplified structural cross-sectional view of the switching mechanism in the liquid cooling structure according to the second embodiment of the present disclosure, which is implemented as an open structure and in a blocked state.

[0029] Figure 6 This is a simplified structural cross-sectional view of the liquid cooling structure according to the third embodiment of the present disclosure, in which the switching mechanism is implemented as a cover plate structure and in the open state.

[0030] Figure 7 This is a simplified structural cross-sectional view of the liquid cooling structure according to the third embodiment of the present disclosure, in which the switching mechanism is implemented as a cover plate structure and in a sealed state.

[0031] Figure 8 Viewed from the stator axis Figure 1 The diagram shows a cross-sectional view of the motor.

[0032] Figure 9 This is a simplified schematic diagram of the flow path of cooling liquid in the motor of an electric drive system in drive mode according to some embodiments of the present disclosure.

[0033] Figure 10 This is a simplified schematic diagram of the flow path of cooling liquid in the motor of an electric drive system in charging mode according to some embodiments of the present disclosure.

[0034] Figure 11 This is a block diagram of an exemplary cooling system according to some embodiments of the present disclosure. Detailed Implementation

[0035] In the following detailed description of replacement embodiments of the present disclosure, it is to be understood that not all of the features of the embodiments described can be necessary in all particular circumstances, or can be desirable when taken in isolation. It is intended, therefore, to be inclusive as well as descriptive, and it is intended in the appended claims to encompass all equivalents within the spirit and scope of the present disclosure. Those skilled in the art will realize that the possible variations and modifications of the present disclosure are numerous and can be practiced in many embodiments other than those described herein. It is therefore intended that the present disclosure not be limited to the particular embodiments described herein, but that the present disclosure include all embodiments falling within the scope of the appended claims.

[0036] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this present disclosure belongs. The terminology used in the description of the present disclosure herein and the claims that follow is not intended to be limiting of the present disclosure. In the description of the present disclosure herein and the claims that follow, "first", "second", and like designations referring to objects and to actions of those objects merely identify different constituent parts of the application for description and do not limit the scope of the application, nor are using the articles "a", "an", and "the" intended to refer to only a singular entity but include the general class of which the reference drawn is but one contention. "Including" and like terms are used herein and are intended to mean that the open-ended term permits additional entities or actions to be present beside those expressly recited in the term. "Connected", "coupled", and "associated" and like terms are not intended to mean only that the entities in question are in physical or mechanical communication or directly connected but also permit remote actions through some intermediary.

[0037] In the present disclosure, all embodiments and preferred embodiments mentioned herein can be combined to form new technical solutions, unless otherwise specified. In the present disclosure, all technical features and preferred features mentioned herein can be combined to form new technical solutions, unless otherwise specified.

[0038] In the description of the embodiments of the present disclosure, the term "and / or" is merely a description of the association relationship of the associated objects, which means that there can be three relationships, for example, A and / or B, which can represent the three cases of A alone, A and B together, and B alone. In addition, the character " / " in this paper generally represents that the front and rear associated objects are a "or" relationship.

[0039] The liquid cooling structure, the motor provided with the liquid cooling structure, and the cooling system according to some embodiments of the present disclosure are described in detail below with reference to the accompanying drawings.

[0040] Figure 1 A structural cross-sectional view of an exemplary electric machine 10 including a liquid cooling structure 100 is shown in accordance with some embodiments of the present disclosure. In some embodiments, the liquid cooling structure 100 of the present disclosure can be disposed at least partially inside a cavity of the electric machine 10. The liquid cooling structure 100 can be configured to adjust the cooling liquid within the electric machine 10 according to a mode in which the electric drive system is in.

[0041] In some embodiments, as shown in FIG. 1, the electric machine 10 can include a stator 20 and a rotor 30. The stator has a plurality of stator teeth and a plurality of stator windings or coils 21 wound on the plurality of stator teeth. The rotor 30 includes a rotor core and a magnetic steel, or includes a rotor core and windings on the rotor core. A physical gap, i.e., a stator-rotor air gap 31 (as shown in FIG. 1) is usually included between the stator 20 and the rotor 30. The air gap 31 not only ensures that the rotor 30 can rotate freely within the cavity formed by the stator 20, but also constitutes a flow path for the cooling liquid to flow through. Figure 1 Figure 9 Figure 10

[0042] The electric machine 10 can be an electric machine for a new energy vehicle. In a driving mode, a rechargeable battery can provide DC power to, for example, an inverter. The inverter can then convert the DC power into AC power and thus drive the electric machine 10 to operate. During the operation of the electric machine 10, the rotor 30 rotates relative to the stator 20, thereby converting electrical energy into mechanical energy. In a charging mode, the electric machine 10 is usually in a stationary state, and the new energy vehicle is charged by an external power source (e.g., a charging pile). In the charging mode, there can be current flowing through the stator windings. Especially when high-power alternating current charging, in the electric drive system involved in the present disclosure, there is a large current flowing through the stator windings, and thus a large amount of heat is generated. The charging electrical energy can be stored in the rechargeable battery for subsequent use.

[0043] ​​​In some embodiments of this disclosure, the stator windings on the stator teeth can be divided into two or more coils. In drive mode, the two or more coils can be connected in parallel or series to form a phase winding. In charging mode, the two or more coils and the corresponding stator teeth can be configured to form a transformer in the charger, as described in patent application filed on March 8, 2021, with application number 202180003354.X, entitled "System and Method for Charging an Electric Vehicle". That patent application is incorporated herein by reference in its entirety. In other words, the motor 10 functions accordingly in both drive mode and charging mode. This contrasts with or differs from the electric drive systems of some other electric vehicles. Some electric drive systems operate only in drive mode, while in charging mode, the charging current does not flow through the drive system (e.g., the motor). Accordingly, for these systems, the drive system has a cooling requirement only in drive mode, while in charging mode, the drive system does not have a cooling requirement.

[0044] In some embodiments, such as Figure 1 As shown, the liquid cooling structure 100 may include a first outlet 101, a switching mechanism 200, and a drive mechanism 300. The first outlet 101 is configured to allow coolant to flow out of the motor 10. The switching mechanism 200 is matched with the first outlet 101. The drive mechanism 300 may be configured to drive the movement of the switching mechanism 200 based on the mode in which the electric drive system is in operation. For example, the drive mechanism 300 may be configured to drive the switching mechanism 200 to open the first outlet 101 in response to the electric drive system being in drive mode. The drive mechanism 300 may also be configured to drive the switching mechanism 200 to at least partially block the first outlet 101 in response to the electric drive system being in charge mode.

[0045] The aforementioned liquid cooling structure enables dynamic switching of the cooling liquid within the motor 10 in both drive and charging modes, meeting the differentiated cooling requirements of each mode. In drive mode, the drive mechanism 300 controls the switching mechanism 200 to open the first outlet 101, removing or at least reducing the amount of cooling liquid within the motor 10. This avoids affecting the movement of rotating components, such as the rotor 30, thus ensuring motor efficiency and output performance. In charging mode, the drive mechanism 300 controls the switching mechanism 200 to at least partially block the first outlet 101, leaving the cooling liquid within the motor 10. This allows for cooling of internal components, especially the stator windings through which current flows directly, reducing the motor 10's temperature and improving charging efficiency while extending system lifespan.

[0046] In addition, the liquid cooling structure described above is simple and easy to implement, without the need for a complex liquid cooling layout. Since there is no need for intensive sealing points, the reliability is high. At the same time, since at least part of the liquid cooling structure is arranged in the motor 10 or integrated with the motor 10, a small-sized arrangement of the liquid cooling structure is achieved.

[0047] In the motor 10, the first outlet 101 is an outlet for the cooling liquid to flow out. In some embodiments, the first outlet 101 can be arranged at the bottom of the internal cavity of the motor 10. The cooling liquid can flow to the first outlet 101 based on gravity and flow out of the motor 10 through the first outlet 101. In other embodiments, the first outlet can also be arranged at other suitable positions. The cooling liquid can flow out of the first outlet due to the push of an external driving force.

[0048] The switching mechanism 200 is a component for adjusting the cooling liquid in the motor, and the first outlet 101 can be opened or at least partially blocked by the movement of the switching mechanism 200. In some embodiments, as described below in conjunction with Figures 2-7 The switching mechanism 200 can include a blocking portion and a driving portion. The blocking portion is configured to at least partially block the first outlet 101. The driving portion is coupled with the driving mechanism 300 to move the blocking portion to a desired state or position.

[0049] It should be understood that the switching mechanism 200 has complete openness in shape design, and its geometric shape can be any shape, including but not limited to circular, square, polygonal, and other shape transformations. The motion trajectory of the switching mechanism 200 can include one or more of linear translation, axial rotation, arc swing, or a combination thereof, including but not limited to gate type, butterfly valve type, flip cover type, and other structural variations.

[0050] The driving mechanism 300 can correspondingly control the switching mechanism 200 based on the state or working mode of the electric drive system. For example, in some embodiments, the driving mechanism 300 can drive the driving portion of the switching mechanism 200 based on a micro control unit (MCU) in response to mode switching of the electric drive system. The MCU can obtain the mode signal of the electric drive system in real time. If it is determined that the driving mode, the MCU can issue a "opening" control instruction to the driving mechanism 300. If it is determined that the charging mode, the MCU can issue a "blocking" control instruction to the driving mechanism 300. The driving mechanism 300 as an actuator can be configured to execute the corresponding control instruction from the MCU.

[0051] It should be understood that the driving mechanism 300 can include but is not limited to motor drive, hydraulic drive, pneumatic drive, or manual mechanical transmission, i.e. any form of kinetic energy conversion that can achieve displacement of the switching mechanism 200 can be included in the present disclosure.

[0052] The following description is provided in relation to the figures Figures 2-7 Some exemplary embodiments of the switching mechanism 200 in the liquid cooling structure 100 are described. Figure 2 A brief structural cross-sectional view of the switching mechanism 200 in the liquid cooling structure 100 according to the first embodiment of the present disclosure is shown, which is implemented as a plug structure and in an open state. Figure 3 A brief structural cross-sectional view of the switching mechanism 200 in the liquid cooling structure 100 according to the first embodiment of the present disclosure is shown, which is implemented as a plug structure and in a plugging state.

[0053] As shown in Figure 2 and Figure 3 The switching mechanism 200 includes a plugging portion 201 and a driving portion 202. The plugging portion 201 can be configured to at least partially plug the first outlet 101. The radial dimension of the plugging portion 201 can be configured to match the size of the first outlet 101, so that the plugging portion 201 can be inserted into the first outlet 101 to at least partially plug the first outlet 101. The driving portion 202 is coupled with the driving mechanism 300 to move the plugging portion 201, for example, upward or downward. In some embodiments, the plugging portion 201 and the driving portion 202 can be integrally formed.

[0054] As shown in Figure 2 When the electric drive system is in the driving mode, the driving mechanism 300 can drive the driving portion 202 of the switching mechanism 200 to move, in response to the mode, so that the plugging portion 201 leaves the first outlet 101, thereby opening the first outlet 101. At this time, the switching mechanism 200 allows the cooling liquid in the cavity of the motor 10 to flow into the first outlet 101 without obstruction and out of the motor 10 via the first outlet 101, as indicated by the dashed arrow in Figure 2 .

[0055] As shown in Figure 3 When the electric drive system is in the charging mode, the driving mechanism 300 can drive the driving portion 202 of the switching mechanism 200 to move, in response to the mode, so that the plugging portion 201 at least partially enters the first outlet 101 to at least partially plug the first outlet 101. Since the radial dimension of the plugging portion 201 is configured to match the size of the first outlet 101, only a small amount of cooling liquid flows into the first outlet 101 through the gap between the plugging portion 201 and the motor 10 housing, or no cooling liquid flows into the first outlet 101, thereby ensuring that a large amount of cooling liquid can be retained in the cavity of the motor 10 in the charging mode. At this time, the switching mechanism 200 can be immersed in the cooling liquid. With the accumulation of the cooling liquid, the cooling liquid can immerse various components in the motor 10 and the environment in the motor 10, especially the stator coil and the stator teeth, to fully cool them.

[0056] Thus, the liquid cooling structure according to the first embodiment of the present disclosure can switch between the opening and blocking of the first outlet based on the mode in which the electric drive system is located, so as to meet the different cooling liquid requirements in the motor cavity under different modes.

[0057] Figure 4 A brief structural cross-sectional view of the switching mechanism 210 in the liquid cooling structure 100 according to the second embodiment of the present disclosure is shown, which is realized as an open hole structure and in an open state. Figure 5 A brief structural cross-sectional view of the switching mechanism 210 in the liquid cooling structure 100 according to the second embodiment of the present disclosure is shown, which is realized as an open hole structure and in a blocked state.

[0058] In this second embodiment, the switching mechanism 210 adopts an open hole type blocking structure. Correspondingly, the first outlet 111 also adopts a structure different from the first embodiment. The driving mechanism 300 can be the same as the first embodiment, and thus will not be described again. Hereinafter, the switching mechanism 210 and the first outlet 111 involved in the second embodiment will be described in detail.

[0059] In Figure 4 , the side wall of the first outlet 111 has a plurality of first openings 112 spaced apart. The switching mechanism 210 includes a blocking part 211 and a driving part 212. The surface of the blocking part 211 has a plurality of second openings 213 matched with the plurality of first openings 112, and a third opening 214 in communication with the cavity of the motor 10. The blocking part 211 can be configured to be aligned with the first openings 112 through the second openings 213, so as to open the first outlet 111. The blocking part 211 can also be configured to be misaligned with the first openings 112 through the second openings 213, so as to block the first outlet 111.

[0060] As Figure 4 shown, the top of the driving part 212 can correspondingly include a fourth opening 215, so that the cooling liquid in the motor 10 can enter the third opening 214 via the fourth opening 215.

[0061] When the electric drive system is in the driving mode, the driving mechanism 300 drives the driving part 212 of the switching mechanism 210 to move, so as to move the blocking part 211 to the final position as Figure 4 shown, i.e., the second openings 213 are aligned with the first openings 112, so that the first outlet 111 is in an open state. At this time, the cooling liquid can flow into the first outlet 111 without obstruction through the aligned openings, and flow out to the outside of the motor 10 via the first outlet 111, as indicated by the dashed arrow in Figure 4 .

[0062] When the electric drive system is in charging mode, the drive mechanism 300 drives the drive portion 212 of the switching mechanism 210 to move, so that the blocking portion 211 at least partially blocks the first outlet 111. For example, the drive mechanism 300 can drive the drive portion 212 of the switching mechanism 210 to move upward or downward. The final position of the blocking portion 211 after movement can be as follows: Figure 5 As shown. At this time, since the second opening 213 is misaligned with the first opening 112, it can at least partially block or prevent the coolant from flowing into the first outlet 111 through the first opening 112 and the second opening 213. Only a small portion of the coolant flows into the first outlet 111 through the gap between the blocked portion 211 and the motor 10 housing and the first opening 112 (e.g., Figure 5 (As indicated by the arrow), or no coolant flows into the first outlet 111, thus ensuring that a large amount of coolant is retained in the cavity of the motor 10 during charging mode. At this time, the switching mechanism 210 is immersed in coolant. As coolant accumulates, it can immerse various components inside the motor 10 and the environment inside the motor 10, especially the stator coils and stator teeth, ensuring sufficient cooling.

[0063] Therefore, the liquid cooling structure according to the second embodiment of this disclosure can switch between opening and blocking the first outlet based on the mode of the electric drive system, so as to meet the different cooling liquid requirements in the motor cavity under different modes.

[0064] Figure 6 A simplified structural cross-sectional view is shown of the switching mechanism 220 in the liquid cooling structure 100 according to the third embodiment of the present disclosure, which is implemented as a cover plate structure and in the open state. Figure 7 A simplified structural cross-sectional view is shown of the switching mechanism 220 in the liquid cooling structure 100 according to the third embodiment of the present disclosure, which is implemented as a cover plate structure and in a sealed state.

[0065] In the third embodiment, the switching mechanism 220 adopts a cover-type sealing structure. The first outlet and the drive mechanism can adopt the same or similar structures as in the first embodiment, and therefore will not be described again. The switching mechanism involved in the third embodiment will be described in detail below.

[0066] The switching mechanism 220, implemented as a cover-type sealing structure, may include a sealing portion 221 and a driving portion 222. The radial dimension of the sealing portion 221 may be set to be larger than the size of the first outlet 101 to cover the first outlet 101.

[0067] like Figure 6As shown, when the electric drive system is in drive mode, the drive mechanism 300 responds to this mode by moving the drive portion 222 of the drive switching mechanism 220 (e.g., moving upwards) to disengage the blocking portion 201 from the top of the first outlet 101, thereby opening the first outlet 101. At this time, the switching mechanism 220 allows the cooling liquid inside the motor 10 cavity to flow unimpeded into the first outlet 101 and out through the first outlet 101 to the outside of the motor 10, such as... Figure 6 As indicated by the dashed arrow in the image.

[0068] like Figure 7 As shown, when the electric drive system is in charging mode, the drive mechanism 300 responds to this mode by moving the drive portion 222 of the switching mechanism 220 (e.g., moving downwards) so that the blocking portion 212 at least partially covers the top of the first outlet 101, thereby at least partially blocking the first outlet 101. Since the radial dimension of the blocking portion 221 is set larger than the size of the first outlet 101 to cover it, only a small amount of coolant flows into the first outlet 101 through the gap between the blocking portion 221 and the motor housing 10, or no coolant flows into the first outlet 101 at all, thus ensuring that a large amount of coolant is retained in the motor cavity during charging mode. At this time, the switching mechanism 220 is immersed in coolant. As coolant accumulates, it can immerse the various components within the motor 10 and the environment within the motor 10, especially the stator coils and stator teeth, ensuring sufficient cooling.

[0069] Therefore, the liquid cooling structure according to the third embodiment of this disclosure can switch between opening and blocking the first outlet based on the mode of the electric drive system, so as to meet the different cooling liquid requirements in the motor cavity under different modes.

[0070] It should be understood that the above combination Figures 2-7 In the described embodiments, as examples, the drive portion of the switching mechanism is shown positioned above the blocking portion. However, this disclosure is not limited thereto. The drive portion may be positioned relative to the blocking portion in other locations, such as any of the various sides, to move the blocking portion to a desired position under the drive of the drive mechanism.

[0071] Return to reference Figure 1 In some embodiments, the liquid cooling structure 100 may further include a second outlet 102. For example... Figure 1As shown, the second outlet 102 is located inside the cavity of the motor 10 and is positioned higher than the rotor 30 inside the motor 10 in the direction of gravity. When the first outlet 101 is blocked or partially blocked, the coolant inside the motor 10 will accumulate accordingly. When the coolant accumulates inside the motor 10 to completely submerge the rotor, the second outlet 102 allows the coolant to flow out of the motor 10. Since the coolant absorbs heat inside the motor 10, the coolant flowing out through the second outlet 102 can further flow to a cooler for cooling.

[0072] In some embodiments, the liquid cooling structure 100 may further include a retaining ring 103. The retaining ring 103 is axially (e.g., Figure 1 (As shown in the x-direction) A ring-shaped baffle piece around the entire circumference. For example... Figure 1 As shown, a portion of the retaining ring 103 (e.g.) Figure 1 The upper portion shown is located within the cavity between the stator 20 and the second outlet 102. One end of the retaining ring 103 (as shown) Figure 1 The left end shown can be connected to the stator 20. The retaining ring 103 can be configured to obstruct the flow of coolant to the second outlet 102 when the electric drive system is in drive mode, and to extend the flow path of coolant within the motor 10 when the electric drive system is in charging mode, as shown in the following combination. Figure 9 and Figure 10 Detailed description. In charging mode, the retaining ring 103 can increase the flow distance of the coolant within the motor 10 and allow the coolant to flow out from the second outlet 102 to the outside of the motor 10.

[0073] In some embodiments, the liquid cooling structure 100 may further include a total outlet 104 (e.g., Figure 9 and Figure 10 (As shown). The main outlet 104 is connected to the first outlet 101 and the second outlet 102 so that the cooling liquid flowing out through the first outlet 101 or the second outlet 102 can eventually flow out of the motor 10.

[0074] In some embodiments, such as Figure 1 As shown, the liquid cooling structure 100 may further include an inlet 105. The inlet 105 can be configured to be located at any position on the motor 10, for example, but not limited to… Figure 1 The inlet 105 shown is located on the upper side of the motor 10. Cooling liquid can flow into the cavity of the motor 10 from this inlet 105 via pressure (e.g., pressure provided by a pump). In some embodiments, the inlet 105 may be positioned adjacent to one end of the motor 10, for example... Figure 1 The left end of the motor 10 is shown. Positioning the inlet 105 adjacent to one end of the motor 10 can extend the path of the cooling liquid within the cavity, as shown in the following combination. Figure 9 and Figure 10 More details are shown below.

[0075] In some embodiments, the liquid cooling structure 100 may further include an annular groove 106. The annular groove 106 may be implemented as an annular rectangular groove surrounding the stator. The annular groove 106 may be located further outward than the stator 20. The annular groove 106 may be positioned adjacent to and in communication with the inlet 105.

[0076] Figure 8 A view from the stator axial direction is shown. Figure 1 The diagram shows a cross-sectional view of the motor 10. A portion of the annular groove 106 (e.g.) Figure 8 The upper side shown is located between the inlet 105 and the stator 20, and is in communication with the inlet 105. The annular groove 106 allows the coolant to flow from the inlet 105 toward the circumference of the motor 10, thereby making the coolant enter the motor 10 more evenly.

[0077] In some embodiments, such as in combination Figure 1 and Figure 8 As shown, the liquid cooling structure 100 may further include an axial groove 107. The axial groove 107 is along the axial direction of the stator 20 (i.e., Figure 1 The x-direction shown, or Figure 8 Multiple axial grooves 107 (perpendicular to the plane of the paper) extend along the circumference of the stator and are distributed therein. The axial grooves 107 are connected to the annular grooves 106. By providing multiple axial grooves 107, the cooling liquid in the annular grooves 106 can be guided and distributed axially, thereby greatly increasing the heat dissipation contact area and fully cooling the stator when the cooling liquid flows.

[0078] Understandably, there are numerous coil gaps 22 in the coils (e.g., stator coils and rotor coils) of the motor 10. Gaps may also exist between the stator 20 and the stator coils 21. These gaps may be distributed in multiple locations along the circumference. These gaps allow coolant to flow through them along the stator axial direction, and thus can also form part of the path for coolant flow.

[0079] Based on the above structure, the different flow paths of the cooling liquid in the motor 10 under different modes will be described in detail below.

[0080] Figure 9 A simplified schematic diagram of the flow path of cooling liquid within the motor 10 in drive mode of an electric drive system according to some embodiments of the present disclosure is shown. Figure 9In the driving mode, the dashed arrows represent the flow path of the cooling liquid. In the driving mode, the liquid cooling structure 100 keeps the first outlet 101 open. The cooling liquid can flow rapidly along the path of the inlet 105, the annular groove 106, the axial groove 107, the coil gap 22 or the gap between the stator and the coil, the first outlet 101, and the total outlet 104, so as to realize the rapid outflow of the cooling liquid from the inside of the motor 10, effectively reducing the resistance when the rotor rotates. In some embodiments, in the driving mode, the supply of cooling liquid to the inside of the motor 10 via the inlet 105 is stopped.

[0081] Figure 10 A schematic diagram of the flow path of the cooling liquid in the motor 10 in the charging mode of the electric drive system according to some embodiments of the present disclosure is shown. In the charging mode, Figure 10 Similar to Figure 9 the dashed arrows represent the flow path of the cooling liquid when the electric drive system is in the charging mode.

[0082] In the charging mode, the first outlet 101 of the liquid cooling structure 100 is blocked. After the cooling liquid reaches the blocked first outlet 101 along the path of the inlet 105, the annular groove 106, the axial groove 107, the coil gap 22 or the gap between the stator and the coil, for example under the action of gravity, the cooling liquid continues to accumulate in the motor cavity, and the liquid level gradually rises. After rising to a certain height, the cooling liquid soaks the rotor through the stator-rotor air gap 31. Finally, the cooling liquid overflows after rising to the second outlet 102 and flows to the total outlet 104. At this time, the stator 20 and the rotor 30 are soaked in the cooling liquid, and efficient heat dissipation is realized in the motor through direct and sufficient liquid cooling contact.

[0083] In combination with Figure 9 It can be seen that, in the driving mode, the arrangement of the baffle ring 103 can make the cooling liquid flow rapidly into the first outlet 101, and then rapidly flow out of the motor 10 via the first outlet 101, thereby rapidly reducing the amount of cooling liquid in the cavity of the motor 10, and ensuring that the mechanical movement of the internal components (such as the rotor) of the motor 10 is not hindered. In combination with Figure 10 It can be seen that, in the charging mode, the arrangement of the baffle ring 103 can prolong or increase the flow path or flow distance of the cooling liquid in the motor 10, thereby realizing more sufficient cooling.

[0084] Some embodiments of the present disclosure also provide a cooling system. Figure 11A block diagram of an exemplary cooling system 1000 according to some embodiments of the present disclosure is shown. In some embodiments, the cooling system 1000 involved in the present disclosure includes a liquid cooling structure 100 at least partially disposed within the electric machine 10, a reservoir 40, a pump 50, a cooler 60 according to any embodiments of the present disclosure. The reservoir 40 is in communication with the total outlet of the cooling liquid of the electric machine 10, and is configured to store the cooling liquid flowing out of the electric machine. In some embodiments, as shown, the reservoir 40 can be configured to be integrated with the electric machine 10, for example, mounted on the side of the electric machine 10, which can save space, eliminate the arrangement of additional cooling liquid pipes, and achieve miniaturization. Figure 8

[0085] The pump 50 is in communication with the reservoir 40, and is configured to extract the cooling liquid from the reservoir 40.

[0086] The cooler 60 is in communication with the pump 50 and the electric machine 10, and is configured to cool the cooling liquid extracted by the pump 50, and deliver the cooled cooling liquid to the electric machine 10.

[0087] In some embodiments, the cooling system 1000 can additionally include a filter 70, as shown by the dashed box in Figure 11 The filter 70 is in communication with the pump 50, and is configured to filter the cooling liquid extracted by the pump 50. The cooler 60 is in communication with the filter 70 and the electric machine 10, and is configured to cool the cooling liquid filtered by the filter 70, and deliver the cooled cooling liquid to the electric machine 10.

[0088] The cooling liquid involved in the present disclosure can include oil-based cooling liquid, and can also include any other suitable cooling liquid.

[0089] The vehicle or vehicle involved in the present disclosure can include any suitable form, private or public, carrying people or carrying things, traveling on land, water or air, recreational or for production vehicles or equipment, etc.

[0090] It should be understood that the description of the position in the present disclosure is relative. In the description of the present disclosure, the terms "up", "down", "top", "bottom", "left", "right", "vertical", "horizontal" and the like indicate the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present disclosure, and do not indicate or imply that the device or component referred to must have a particular orientation, or be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present disclosure. In other embodiments where the placement direction of the device or component is opposite or different from the direction shown in the figure, these positional descriptions can be changed accordingly.

[0091] ​It is to be understood that the above description is intended to be illustrative, and not restrictive. For example, the above-described embodiments (and / or aspects thereof) can be used in combination with each other. In addition, many modifications can be made to adapt a particular situation or material to the teachings of the various embodiments of the present disclosure without departing from its scope. The various embodiments are merely illustrative aspects of the techniques described herein, and do not constitute limitations on the present disclosure. Many other embodiments of the disclosure can be apparent to those skilled in the art upon reviewing the above description, and it is intended to embrace all such embodiments and modifications in the scope of the appended claims along with the full scope of equivalents to which such claims are entitled.

Claims

1. A liquid cooling structure disposed at least partially within an electric machine, the liquid cooling structure comprising: a first outlet configured to allow a cooling liquid to flow out of the electric machine; a switching mechanism matched with the first outlet; and a driving mechanism configured to drive movement of the switching mechanism based on a mode in which the electric drive system is in, including: in response to the electric drive system being in a driving mode, driving the switching mechanism to move to open the first outlet; in response to the electric drive system being in a charging mode, driving the switching mechanism to move to at least partially block the first outlet. the switching mechanism comprising a blocking portion configured to at least partially block the first outlet and a driving portion coupled with the driving mechanism to move the blocking portion.

2. The liquid cooling structure of claim 1, wherein 3.The liquid cooling structure of claim 2, wherein: a radial dimension of the blocking portion matches a size of the first outlet to enable the blocking portion to be inserted into the first outlet. 4.The liquid cooling structure of claim 2, wherein: a sidewall of the first outlet has a plurality of first openings spaced apart, a surface of the blocking portion has a plurality of second openings matched with the plurality of first openings and a third opening in communication with a cavity of the electric machine, the blocking portion is configured to: block the first outlet by the second openings being misaligned with the first openings, open the first outlet by the second openings being aligned with the first openings. 5.The liquid cooling structure of claim 2, wherein: a radial dimension of the blocking portion is greater than a size of the first outlet to cover the first outlet. 6.The liquid cooling structure of claim 1, wherein: the first outlet is disposed at a bottom of the cavity of the electric machine. further comprising:

7. The liquid cooling structure of claim 1, wherein, a second outlet disposed within the electric machine and at a position higher than a rotor in the electric machine in a direction of gravity. further comprising:

8. The liquid cooling structure of claim 7, wherein, a baffle ring configured to impede the cooling liquid from flowing to the second outlet when the electric drive system is in the driving mode and to extend a flow path of the cooling liquid within the electric machine when the electric drive system is in the charging mode. further comprising:

9. The liquid cooling structure of claim 7, wherein, a total outlet in communication with the first outlet and the second outlet. further comprising:

10. The liquid cooling structure of claim 1, wherein, an inlet configured to allow the cooling liquid to flow into the cavity of the electric machine from the inlet. the liquid cooling structure further comprising an annular groove on a stator adjacent to the inlet.

11. The liquid cooling structure of claim 10, wherein, the liquid cooling structure further comprising a plurality of axial grooves in the stator extending in an axial direction of the stator and distributed in a circumferential direction of the stator, the axial grooves being in communication with the annular groove.

12. The liquid cooling structure of claim 11, wherein, the driving mechanism comprising one of:

13. The liquid cooling structure of claim 1, wherein, a motor driving mechanism, a hydraulic driving mechanism, a pneumatic driving mechanism, or a manual mechanical transmission mechanism. the movement of the switching structure comprising one or more of a linear translation, an axial rotation, an arc swing, or a combination thereof.

14. The liquid cooling structure of claim 1, wherein, 15.An electric machine configured to operate in a driving mode and a charging mode of an electric drive system, the electric machine comprising: ​ a stator having a plurality of stator teeth and a plurality of stator windings wound on the plurality of stator teeth, wherein in the charging mode, a charging current flows through at least a portion of the stator windings; a rotor comprising a rotor core and a magnetic steel, or comprising a rotor core and windings on the rotor core; and and The liquid cooling structure of any one of claims 1-14.

16. A cooling system for an electric machine, characterized in that Comprising: The liquid cooling structure of any one of claims 1-14; a reservoir in communication with the electric machine and configured to store the cooling liquid flowing out of the electric machine; a pump in communication with the reservoir and configured to draw the cooling liquid from the reservoir; a cooler in communication with the pump and the electric machine and configured to cool the cooling liquid drawn by the pump and deliver the cooled cooling liquid to the electric machine.

17. The cooling system of claim 16, wherein, The reservoir is integrated with the electric machine.

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