Cooling system of electric machine, cooling system of vehicle and vehicle

Abstract

This application provides a cooling system for an electric motor, a cooling system for a vehicle, and a vehicle. The electric motor cooling system includes a heat exchanger, a first cooling channel, and a second cooling channel. The heat exchanger is located outside the electric motor and communicates with the external cooling channel, through which the cooling medium in the external cooling channel flows. The first cooling channel is located between the electric motor housing and the heat exchanger, and a first cooling medium flowing through the first cooling channel exchanges heat with the cooling medium flowing through the heat exchanger. The second cooling channel is located between the cooling medium flow path inside the electric motor housing and the heat exchanger, and has a cooling medium outlet facing the rotor assembly of the electric motor. A second cooling medium flowing through the second cooling channel exchanges heat with the cooling medium flowing through the heat exchanger. This application enables the first and second cooling media to cool the electric motor housing, stator core, and rotor assembly, improving the cooling effect of the electric motor and adapting to various operating conditions.

Description

Technical Field

[0001] This utility model relates to the technical field of motor cooling, and in particular to a motor cooling system. Background Technology

[0002] An electric motor is a crucial component that converts electrical energy into mechanical energy. It typically consists of a rotor, stator, copper wire windings, and a housing / end cover. With the continuous increase in demand for high-power and miniaturized motors, insufficient heat dissipation efficiency has become a core bottleneck restricting motor performance and reliability. Especially when operating at high power, motors are prone to overheating due to copper wire losses, excessively high stator winding temperatures, and core losses. This can even lead to the failure of the insulation layer on the motor windings or irreversible failure of the motor rotor.

[0003] The cooling system of an electric motor is used to cool the motor. It typically uses a cooling medium to cool the rotor, stator, and windings to prevent overheating during operation. Traditional cooling systems generally use a single medium, such as pure air cooling, pure oil cooling, or pure water cooling. However, in the fully enclosed environment of a motor, high-power operation leads to the accumulation of hot air that is difficult to dissipate. Therefore, pure air cooling systems are not very effective. Pure oil cooling systems, due to the high viscosity and poor flowability of the cooling oil, cannot provide effective cooling over a wide area. As for pure water cooling systems, cooling water circulation pipes need to be installed inside the motor. These pipes can experience localized overheating due to water pressure, or some sections may be too weak, also failing to achieve optimal cooling over a large area. Furthermore, single-medium cooling systems are suitable for diverse operating conditions.

[0004] Therefore, existing motor cooling systems suffer from poor cooling performance and are unable to adapt to diverse operating conditions. Utility Model Content

[0005] The purpose of this invention is to solve the problems of poor cooling effect and inability to adapt to diverse working conditions in the existing motor cooling system.

[0006] To address the aforementioned problems, this utility model discloses a cooling system for an electric motor, comprising: a heat exchanger disposed outside the motor and communicating with an external cooling channel, wherein a cooling medium in the external cooling channel flows through the heat exchanger; a first cooling channel disposed between the motor housing and the heat exchanger, wherein a first cooling medium flowing through the first cooling channel exchanges heat with the cooling medium flowing through the heat exchanger; and a second cooling channel disposed between the cooling medium flow path inside the motor housing and the heat exchanger, having a cooling medium outlet facing the rotor assembly of the motor, wherein a second cooling medium flowing through the second cooling channel exchanges heat with the cooling medium flowing through the heat exchanger.

[0007] By employing the above scheme, a first cooling channel is positioned between the motor housing and the heat exchanger, and a second cooling channel is positioned between the cooling medium flow path within the motor housing and the heat exchanger. The low-temperature first and second cooling media are guided to the motor through these channels. This allows the first cooling medium in the first channel to cool the motor housing and stator core, and the second cooling medium in the second channel to cool the rotor assembly. This reduces the risk of motor failure or short circuits during long-term operation at peak or high power, ensuring motor efficiency. Furthermore, the first and second cooling channels can cool different parts of the motor. When the motor operates in different states or conditions, different cooling channels can be selected to cool different parts of the motor, reducing energy consumption while maintaining effective cooling.

[0008] According to another specific embodiment of the present invention, the cooling system for an electric motor disclosed in this embodiment includes a heat exchanger comprising a cooling medium passage, and a first cooling medium passage and a second cooling medium passage respectively disposed adjacent to the cooling medium passage; furthermore, the outlet of the external cooling channel is connected to the inlet of the cooling medium passage, and the outlet of the cooling medium passage leads to the outside of the heat exchanger; the upstream portion of the first cooling channel connects the outlet of the motor housing flow path within the motor housing to the inlet of the first cooling medium passage, and the downstream portion connects the outlet of the first cooling medium passage to the inlet of the motor housing flow path; the first cooling medium from the motor housing flow path passes through the upstream portion of the first cooling channel. The first cooling medium enters the inlet of the first cooling medium passage and re-enters the motor housing flow path through the downstream portion of the first cooling flow path from the outlet of the first cooling medium passage; the upstream portion of the second cooling flow path connects the outlet of the cooling medium flow path inside the motor housing with the inlet of the second cooling medium passage, and the downstream portion connects the outlet of the second cooling medium passage with the inlet of the cooling medium flow path. The second cooling medium from the cooling medium flow path enters the inlet of the second cooling medium passage through the upstream portion of the second cooling flow path and re-enters the cooling medium flow path through the downstream portion of the second cooling medium passage from the outlet of the second cooling medium passage; wherein, the cooling medium flow path has an oil collection port disposed inside the motor housing.

[0009] With the above scheme, the first cooling channel and the second cooling channel are respectively set between the motor housing and the heat exchanger, and between the cooling medium flow path in the motor housing and the heat exchanger. This can accurately cool the motor housing and the stator core, or cool the rotor assembly and the ends of the copper wire winding, further improving the cooling effect.

[0010] According to another specific embodiment of the present invention, the cooling system of the motor disclosed in this embodiment further includes: a third cooling channel, which is disposed in the stator slot of the motor and communicates with the external cooling channel, and the cooling medium in the external cooling channel flows through the third cooling channel; wherein, the inlet of the third cooling channel is connected to the outlet of the external cooling channel and the outlet is connected to the outside of the motor.

[0011] By adopting the above scheme, the third cooling channel can directly cool the stator slots that are not easily cooled. The cooling medium in the external cooling channel is directly introduced into the third cooling channel, and the copper wire windings and insulation layer in the stator slots are cooled through the third cooling channel, which reduces the risk of insulation layer failure when the motor is running at high power.

[0012] According to another specific embodiment of the present invention, the cooling system for the motor disclosed in this embodiment of the present invention includes an external cooling channel connected to a heat exchanger via a regulating valve group, the regulating valve group including a three-way valve; wherein...

[0013] The inlet of the three-way valve is connected to the external cooling channel, one outlet of the three-way valve is connected to the inlet of the cooling medium passage, and the other outlet is connected to the inlet of the third cooling channel; or, the regulating valve group includes two check valves, the inlets of both check valves are connected to the external cooling channel, the outlet of one check valve is connected to the inlet of the cooling medium passage, and the outlet of the other check valve is connected to the inlet of the third cooling channel; and, a flow regulating valve is connected in series upstream of the inlet of the regulating valve group, the flow regulating valve being a switching valve and / or an expansion valve.

[0014] By adopting the above scheme and setting the regulating valve group as a three-way valve, the number of valves is reduced, the pipeline design is simplified, the integration of the valve group is improved, and space and cost are saved. The setting of the flow regulating valve allows the flow path in the flow path to be controlled, reducing energy waste and lowering operating costs.

[0015] According to another specific embodiment of the present invention, the cooling system of the motor disclosed in this embodiment of the present invention has a first cooling pump provided in the upstream part of the first cooling channel and a first cooling valve provided in the downstream part; and a second cooling pump provided in the upstream part of the second cooling channel and a second cooling valve provided in the downstream part.

[0016] By adopting the above scheme, the flow paths of the first and second cooling channels can be easily controlled by the setting of the first and second cooling valves. The setting of the first and second cooling pumps can improve the liquid flow efficiency, thereby improving the motor cooling efficiency.

[0017] According to another specific embodiment of the present invention, the motor cooling system disclosed in this embodiment includes the following operating conditions of the motor: a first operating condition in which the driving speed of the motor is less than a preset speed threshold and the driving current is less than a preset current threshold; a second operating condition in which the driving speed is less than the speed threshold and the driving current is greater than the current threshold; a third operating condition in which the driving speed is greater than the speed threshold and the driving current is less than the current threshold; and a fourth operating condition in which the driving speed is greater than the speed threshold and the driving current is greater than the current threshold; wherein, in the first operating condition, the regulating valve group shuts off the passage to the heat exchanger and the third cooling channel, and the first cooling valve, the first cooling pump, the second cooling valve, and the second cooling pump are all open.

[0018] In the second operating condition, the regulating valve group opens the passage to the heat exchanger and the third cooling channel, and the first cooling valve and the first cooling pump are closed, while the second cooling valve and the second cooling pump are open; in the third operating condition, the regulating valve group opens the passage to the heat exchanger and closes the passage to the third cooling channel, and the first cooling valve and the first cooling pump are open, while the second cooling valve and the second cooling pump are closed; in the fourth operating condition, the regulating valve group opens the passage to the heat exchanger and the third cooling channel, and the first cooling valve, the first cooling pump, the second cooling valve, and the second cooling pump are all open.

[0019] By adopting the above scheme, through the coordination of the regulating valve group, the first cooling pump, the first cooling valve, the second cooling pump, and the second cooling valve, cooling can be carried out in different zones, which facilitates precise temperature control and improves the cooling efficiency of the cooling system. Furthermore, it can also enable the motor to activate different cooling channels to execute different cooling strategies under different operating conditions, thereby reducing energy consumption while ensuring the cooling of the motor.

[0020] According to another specific embodiment of the present invention, the cooling system of the motor disclosed in this embodiment includes a second cooling channel disposed within the rotor shaft of the motor, and the rotor shaft having a plurality of through holes serving as cooling medium outlets in the circumferential direction; the plurality of through holes extend through the sidewall of the rotor shaft, along the radial direction of the rotor shaft, and / or toward a first direction, wherein the first direction extends obliquely relative to the radial direction; or, the second cooling channel is disposed within the motor housing, extends along the inner wall of the motor housing, and has a cooling medium outlet toward the rotor assembly of the motor; furthermore, the cooling system also includes a detection component, which is a temperature detection component disposed at the winding of the motor, and the temperature detection component is connected to an external valve regulating component; and the external valve regulating component is connected to a flow regulating valve.

[0021] By adopting the above scheme, the flow regulating valve can adjust its on / off state or flow rate according to the temperature at the motor winding, thereby controlling the flow rate of the cooling medium in the flow path and improving the cooling efficiency of the motor.

[0022] According to another specific embodiment of the present invention, the cooling system of the motor disclosed in this embodiment of the present invention includes a first cooling medium of coolant, a second cooling medium of cooling oil, and a cooling medium of refrigerant; the motor is an on-board motor, and the external cooling channel is connected to the vehicle's passenger compartment cooling system and / or battery cooling system; wherein the heat exchanger is connected to the passenger compartment cooling system and / or battery cooling system in parallel with the external cooling channel, and the outlet of the cooling medium passage and the third cooling channel are both connected to the passenger compartment cooling system and / or battery cooling system; and the external cooling channel includes a compressor and a condenser connected in series, with the compressor located upstream of the condenser.

[0023] By adopting the above scheme, different cooling media are introduced into different cooling channels, making the entire cooling system compatible with multiple cooling media. Specific cooling media can be selected to cool different parts according to cooling needs, further improving the cooling efficiency of the cooling system.

[0024] The present invention discloses a vehicle cooling system, including a motor cooling system as described in any of the above embodiments, a passenger compartment cooling system, wherein the motor cooling system and the passenger compartment cooling system are connected via a heat exchanger of the motor cooling system; and / or a battery cooling system, wherein the battery cooling system and the passenger compartment cooling system are connected via a heat exchanger.

[0025] This utility model discloses a vehicle including a cooling system for a vehicle as described in the above embodiments.

[0026] The beneficial effects of this utility model are:

[0027] The motor cooling system provided in this application involves placing a first cooling channel between the motor housing and the heat exchanger, and a second cooling channel between the cooling medium flow path within the motor housing and the heat exchanger. Low-temperature first and second cooling media are guided to the motor through these channels. The first cooling medium in the first channel cools the motor housing and stator core, while the second cooling medium in the second channel cools the rotor assembly. This reduces the risk of failure or short circuits during long-term operation at peak or high power, ensuring motor efficiency. Furthermore, the first and second cooling channels can cool different parts of the motor. When the motor operates in different states or conditions, different cooling channels can be selected to cool different parts of the motor, reducing energy consumption while maintaining effective cooling.

[0028] The vehicle cooling system provided in this application connects the motor cooling system with the passenger compartment cooling system and / or the battery cooling system. This allows the motor to share components such as the compressor and condenser of the passenger compartment air conditioning or battery cooling system when cooling, reducing additional piping and heat exchangers, thus lowering hardware costs and installation space. Furthermore, it eliminates the need for multiple circulation pumps and water tanks, reducing system weight and improving overall vehicle energy efficiency. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the cooling system for the motor provided in an embodiment of the present invention;

[0030] Figure 2 This is a schematic diagram of the connection structure of the motor cooling system provided in this embodiment of the utility model;

[0031] Figure 3 This is a schematic diagram of the first and second cooling channels of the motor cooling system provided in this embodiment of the present invention during cooling.

[0032] Figure 4 This is a schematic diagram of the third cooling channel of the motor cooling system provided in this embodiment of the present invention during cooling.

[0033] Figure 5 This is a schematic diagram of another connection structure of the motor cooling system provided in this embodiment of the utility model.

[0034] Explanation of reference numerals in the attached figures:

[0035] 1. Heat exchanger; 2. First cooling channel; 21. First cooling pump; 22. First cooling valve; 3. Second cooling channel; 31. Second cooling pump; 32. Second cooling valve; 4. Motor; 41. Cooling medium flow path; 411. Oil collector; 42. Cooling medium outlet; 43. Stator slot; 44. Copper wire winding; 45. Insulation layer; 46. Motor housing flow path; 47. Stator core; 48. Rotor shaft; 5. External cooling channel; 51. Compressor; 52. Condenser; 53. Fan; 6. Third cooling channel; 7. Regulating valve assembly; 8. Switch valve; 9. Expansion valve. Detailed Implementation

[0036] Example 1:

[0037] As mentioned in the background section, motors experience overheating when operating at high power. Specifically, when a motor operates at peak power, the stator winding temperature becomes excessively high due to copper wire losses. If the stator winding temperature exceeds the maximum temperature of the motor's insulation class, the insulation layer on the stator winding will fail, posing a short-circuit risk. When a motor continuously operates at power higher than its rated power, the temperature on the rotor steel sheets will continuously increase due to core losses, posing an irreversible failure risk. This is particularly true for permanent magnet motors, where core losses also cause the permanent magnet temperature to continuously increase. When this temperature exceeds the Curie temperature of the permanent magnet, the motor will also fail. During motor operation, it is inevitable that the motor will operate at peak power, i.e., at maximum current and maximum torque. At this point, the motor generates the most heat. Prolonged operation at peak power significantly increases the risk of failure and short circuits.

[0038] To address the aforementioned technical problems, this embodiment provides a motor cooling system, comprising a heat exchanger, a first cooling channel, and a second cooling channel. The first and second cooling channels can utilize their respective cooling media to cool different parts of the motor under different conditions, thereby achieving rapid and effective cooling of the motor under various operating conditions. Furthermore, the first and second cooling channels can exchange heat with the cooling medium flowing through the heat exchanger, thus enabling continuous cooling of the motor.

[0039] Next, combined Figures 1-5 The cooling system for the motor provided in this embodiment will be described.

[0040] The motor cooling system provided in this embodiment refers to... Figure 1 It includes a heat exchanger 1, a first cooling channel 2, and a second cooling channel 3.

[0041] refer to Figure 2 The heat exchanger 1 is located outside the motor 4 and communicates with the external cooling channel 5. The cooling medium in the external cooling channel 5 flows through the heat exchanger 1. The cooling medium in the external cooling channel 5 continuously flows through the heat exchanger 1, and a low-temperature cooling medium always flows inside the heat exchanger 1 to absorb heat. It should be noted that the heat exchanger 1 in this embodiment is preferably a plate heat exchanger. Plate heat exchangers have complex flow channels formed by corrugated plates, resulting in a high heat transfer coefficient. Furthermore, plate heat exchangers have a compact structure and their arrangement can be adjusted by adding or removing plates, quickly changing the heat exchange area and flow path combination, thus better adapting to the needs of different operating conditions. Therefore, setting the heat exchanger 1 as a plate heat exchanger can better adapt to the needs of different operating conditions and the need for miniaturization of the cooling system, and can also improve the cooling efficiency of the cooling system. Of course, those skilled in the art can choose a shell-and-tube heat exchanger, which has a lower cost.

[0042] The first cooling channel 2 is disposed between the motor housing and the heat exchanger 1, and the first cooling medium flowing through the first cooling channel 2 exchanges heat with the cooling medium flowing through the heat exchanger 1. The first cooling channel 2 guides the low-temperature first cooling medium to the motor housing, thereby cooling the motor housing. Figure 3 The stator core 47 shown in the diagram directly contacts the motor housing for heat conduction, cooling both the motor housing and the stator. Furthermore, the first cooling channel 2 returns the first cooling medium, which has absorbed heat from the motor housing, to the heat exchanger 1 for heat exchange, and then redirects the cooled first cooling medium back to the motor housing.

[0043] The second cooling channel 3 is located between the cooling medium flow path 41 and the heat exchanger 1 within the motor housing, and has a cooling medium outlet 42 facing the rotor assembly of the motor 4. The second cooling medium flowing through the second cooling channel 3 exchanges heat with the cooling medium flowing through the heat exchanger 1. The second cooling channel 3 guides the low-temperature second cooling medium to the cooling medium outlet 42, thereby cooling the rotor assembly. The second cooling medium that has absorbed heat from the rotor assembly flows back to the heat exchanger 1 through the cooling medium flow path 41 within the motor housing for heat exchange. The low-temperature second cooling medium flowing out of the heat exchanger 1 re-enters the second cooling channel 3 and is guided to the cooling medium outlet 42.

[0044] It should be noted that the rotor assembly in this embodiment includes, but is not limited to, the rotor core, and... Figure 3 The rotor shaft 48 is shown in the figure. When the motor 4 is a permanent magnet motor, it may also include permanent magnets embedded in or inside the iron core.

[0045] With this structure, by placing the first cooling channel 2 between the motor housing and the heat exchanger 1, and placing the second cooling channel 3 between the cooling medium flow path 41 inside the motor housing and the heat exchanger 1, the first cooling medium in the first cooling channel 2 and the second cooling medium in the second cooling channel 3 can exchange heat with the cooling medium flowing through the external cooling channel 5 of the heat exchanger 1. The low-temperature first and second cooling media are guided to the motor 4 through the first cooling channel 2 and the second cooling channel 3, so that the first cooling medium in the first cooling channel 2 can cool the motor housing and stator core 47, and the second cooling medium in the second cooling channel 3 can cool the rotor assembly. In this way, the risk of failure or short circuit of the motor 4 when operating at peak power or high power for a long time is reduced, ensuring the working efficiency of the motor 4. Furthermore, the first cooling channel 2 and the second cooling channel 3 can cool different parts of the motor 4. When the motor 4 is operating in different working states or under different conditions, different cooling channels can be selected to cool different parts of the motor 4, reducing energy consumption while ensuring the cooling effect of the motor 4.

[0046] Further, refer to Figure 2 The heat exchanger 1 includes a cooling medium passage and a first cooling medium passage and a second cooling medium passage, which are respectively arranged adjacent to the cooling medium passage. The cooling medium in the first cooling medium passage and the second cooling medium passage can exchange heat with the cooling medium in the cooling medium passage. The outlet of the external cooling channel 5 is connected to the inlet e of the cooling medium passage, and the outlet f of the cooling medium passage leads to the outside of the heat exchanger 1.

[0047] Further, refer to Figure 2 The upstream portion of the first cooling channel 2 connects the outlet a of the motor housing flow path 46 within the motor housing with the inlet b of the first cooling medium passage; the downstream portion connects the outlet c of the first cooling medium passage with the inlet d of the motor housing flow path 46. The first cooling medium from the motor housing flow path 46 enters the inlet b of the first cooling medium passage via the upstream portion of the first cooling channel 2, and re-enters the motor housing flow path 46 from the outlet c of the first cooling medium passage via the downstream portion of the first cooling channel 2. (Refer to...) Figure 3 The motor housing flow path 46 is located inside the motor housing. The first cooling medium flowing into it can cool the motor housing and, through heat conduction, also cool the stator core 47 that is in contact with the motor housing. Specifically, the motor housing flow path 46 can be a liquid channel formed inside the motor housing. This method not only ensures the cooling effect but also avoids affecting the arrangement of other components by placing the flow path inside the housing. In addition, the motor housing flow path 46 can be set close to the outer or inner side of the motor housing, thereby reducing the difficulty of flow path arrangement. In this embodiment, liquid channels can also be provided in both the motor housing and the front and rear ends of the motor 4 to cool the air at both ends of the motor 4 while cooling the motor housing, thereby indirectly cooling the motor 4.

[0048] Further, refer to Figure 2 The upstream portion of the second cooling channel 3 connects the outlet g of the cooling medium flow path 41 inside the motor housing with the inlet h of the second cooling medium passage; the downstream portion connects the outlet m of the second cooling medium passage with the inlet n of the cooling medium flow path 41. The second cooling medium from the cooling medium flow path 41 enters the inlet h of the second cooling medium passage via the upstream portion of the second cooling channel 3, and re-enters the cooling medium flow path 41 from the outlet m of the second cooling medium passage via the downstream portion of the second cooling channel 3. (Refer to...) Figure 3 The cooling medium flow path 41 has an oil collection port 411 located inside the housing of the motor 4.

[0049] Furthermore, refer to Figure 3The first embodiment provides a second cooling channel 3 configuration as follows: the second cooling channel 3 is disposed within the rotor shaft 48 of the motor 4, and the rotor shaft 48 has multiple through holes serving as cooling medium outlets 42 in its circumferential direction. Furthermore, the multiple through holes penetrate the sidewall of the rotor shaft 48, extend along the radial direction of the rotor shaft 48, and / or towards a first direction, wherein the first direction extends obliquely relative to the radial direction. That is, the through holes can be disposed along the radial direction of the rotor shaft 48 to directly cool the ends of the copper wire winding 44 and the rotor core. The through holes can also extend obliquely to cool the rotor core and permanent magnets. By changing the configuration of the cooling medium outlets 42, the cooling area can be flexibly adjusted, allowing for targeted cooling of the desired locations, further improving the cooling effect. With this configuration, the second cooling channel 3 does not occupy space within the motor 4, which is beneficial for the miniaturization of the motor 4. Furthermore, the second cooling medium is ejected by the high-speed rotation of the rotor shaft 48. The second cooling medium, due to inertia, can cool the end of the copper wire winding 44 and the rotor core or permanent magnet part, eliminating the need for a pressurizing component to accelerate the ejection of the cooling medium and reducing the overall cost.

[0050] The second cooling channel 3 provided in this embodiment is configured as follows: the second cooling channel 3 is disposed inside the motor housing, extends along the inner wall of the motor housing, and has a cooling medium outlet 42 facing the rotor assembly of the motor 4. In other words, the second cooling channel 3 can be a fixed liquid channel disposed inside the motor housing, and the cooling medium outlet 42 can be configured as a nozzle, allowing oil spray cooling of the rotor assembly and even other parts of the motor 4. This configuration allows for flexible placement of the cooling medium outlet 42, enabling the use of the second cooling medium to cool any part inside the motor housing, thus improving the cooling effect.

[0051] Further, refer to Figure 2 The motor's cooling system also includes a third cooling channel 6. (Reference) Figure 4 The third cooling channel 6 is located within the stator slot 43 of the motor 4 and communicates with the external cooling channel 5. The cooling medium in the external cooling channel 5 flows through the third cooling channel 6. (Continue to refer to...) Figure 4 The stator slot 43 contains copper wire windings 44 formed by winding copper wire, with an insulation layer 45 between each layer of copper wire windings 44. An external cooling channel 5 is directly disposed within the stator slot 43 of the motor 4. This structure allows the cooling medium in the external cooling channel 5 to be directly introduced into a third cooling channel 6. The third cooling channel 6 can cool the copper wire windings 44 and the insulation layer 45 within the stator slot 43, reducing the risk of insulation layer 45 failure when the motor 4 operates at high power. (Refer to...) Figure 2The inlet o of the third cooling channel 6 is connected to the outlet p of the external cooling channel 5, and the outlet p is connected to the outside of the motor 4. In this embodiment, by setting the third cooling channel 6, which is arranged in the stator slot 43 and connected to the external cooling channel 5, the windings in the stator slot 43 can be directly cooled by the cooling medium. Compared with the method of transferring the temperature in the stator slot 43 to the motor housing for cooling by heat conduction, this method can directly and efficiently cool the copper wire windings 44 and the insulation layer 45 in the stator slot 43. Even when the motor 4 is continuously operating under high current conditions, the copper wire windings 44 can be maintained within a suitable temperature range, improving the reliability and efficiency of the motor 4.

[0052] Further, refer to Figure 2 The external cooling channel 5 is connected to the heat exchanger 1 via a regulating valve assembly 7. The first implementation of the regulating valve assembly 7 in this embodiment is as follows: the regulating valve assembly 7 includes a three-way valve. The inlet x of the three-way valve is connected to the external cooling channel 5, one outlet y of the three-way valve is connected to the inlet e of the cooling medium passage, and the other outlet z is connected to the inlet o of the third cooling channel 6. Setting the regulating valve assembly 7 as a three-way valve reduces the number of valves, simplifies the piping design, improves the integration of the valve assembly, and saves space and cost.

[0053] The second implementation of the regulating valve assembly provided in this embodiment (not shown in the figure) includes two check valves. The inlets of both check valves are connected to the external cooling channel 5. The outlet of one check valve is connected to the inlet of the cooling medium passage, and the outlet of the other check valve is connected to the inlet of the third cooling channel 6. Setting the regulating valve assembly as two check valves results in a simple structure and low failure rate of the check valves, facilitating maintenance and installation. Furthermore, the check valves can independently control different pipelines, allowing for convenient adjustment of the flow path within the pipeline and demonstrating good adaptability to different flow paths.

[0054] Further, refer to Figure 2A flow regulating valve is connected in series upstream of the inlet of the regulating valve assembly 7. This flow regulating valve can be a switching valve 8 and / or an expansion valve 9. In this embodiment, the flow regulating valve is a combination of a switching valve 8 and an expansion valve 9, with the switching valve 8 positioned upstream of the expansion valve 9. The switching valve 8 controls the opening and closing of the flow path, while the expansion valve 9 regulates the flow rate. Furthermore, the simultaneous placement of the switching valve 8 and the expansion valve 9 provides dual protection for the flow path, ensuring that the flow path remains unaffected even if either valve leaks. The combined operation of the switching valve 8 and the expansion valve 9 can adapt to complex operating conditions, particularly for flow paths with varying operating conditions and high pressure ratios. Furthermore, in this embodiment, the switching valve 8 can be connected in series only upstream of the inlet of the regulating valve assembly 7, allowing for rapid closing or opening of the flow path without the need for a complex drive mechanism, resulting in a simpler structure and lower cost. Currently, the expansion valve 9 can also be connected in series only upstream of the inlet of the regulating valve assembly 7. The expansion valve 9 can regulate the liquid flow rate and has good dynamic regulation capabilities. Moreover, the expansion valve 9 allows for precise flow control, reducing energy waste and lowering operating costs.

[0055] Further, refer to Figure 2 The first cooling channel 2 has a first cooling pump 21 installed upstream and a first cooling valve 22 installed downstream. The second cooling channel 3 has a second cooling pump 31 installed upstream and a second cooling valve 32 installed downstream. The first cooling valve 22 and the second cooling valve 32 can be either a switching valve 8 or an expansion valve 9. The installation of the first cooling valve 22 and the second cooling valve 32 allows for convenient on / off control of the flow paths of the first cooling channel 2 and the second cooling channel 3. The installation of the first cooling pump 21 and the second cooling pump 31 improves the flow efficiency of the liquid, thereby improving the cooling efficiency of the motor 4.

[0056] Furthermore, in this embodiment, the first cooling medium is coolant, the second cooling medium is cooling oil, and the cooling medium is refrigerant. By introducing different cooling media into different cooling channels, the entire cooling system is compatible with multiple cooling media. Specific cooling media can be selected to cool different parts according to cooling needs, further improving the cooling efficiency of the cooling system. Specifically, coolant has high heat dissipation efficiency and fast cooling speed. When using coolant to cool the rapidly heating motor housing, the temperature of the motor housing can be quickly reduced, and the temperature of the stator core 47 can also be reduced through heat conduction. Moreover, coolant is prone to scale buildup and requires regular maintenance, while the first cooling channel 2, located between the motor housing and the heat exchanger 1, is easier to disassemble and maintain compared to other parts. Cooling oil has better thermal stability and lubricity. Cooling the copper wire winding 44 and rotor assembly with cooling oil will not cause wear or other damage to the copper wire winding 44 and rotor assembly, which is beneficial for maintaining the service life and stability of the motor 4. The refrigerant has stable thermodynamic properties and a fast cooling speed. When the refrigerant is introduced into the heat exchanger 1 to absorb heat from the coolant and cooling oil, the heat absorption effect is better, improving the overall cooling effect of the cooling system. The refrigerant is used directly to cool the copper wire winding 44 and the insulation layer 45 in the stator slot 43. Even the multi-layered copper wire winding 44 can be cooled quickly, and the copper wire winding 44 can continue to operate at a low temperature, improving the stability of the motor 4.

[0057] Next, combined Figure 2 and Figure 3 The water cooling process when the first cooling medium is coolant is described as follows: The first cooling valve 22 is opened, and the first cooling pump 21 drives the coolant to exchange heat with the cooling medium in the heat exchanger 1. The cooled coolant after heat exchange enters the motor housing flow path 46, where forced convection heat exchange occurs between the coolant and the motor housing wall, directly cooling the motor housing. The motor housing is in direct contact with the stator core 47, and the stator core 47 is cooled through conduction between solids.

[0058] Combination Figure 2 and Figure 3 The oil cooling process when the second cooling medium is cooling oil is described as follows: The second cooling valve 32 is opened, and the second cooling pump 31 drives the cooling oil to exchange heat with the cooling medium in the heat exchanger 1. The low-temperature cooling oil after heat exchange enters the cooling medium flow path 41. Under the pressure of the second cooling pump 31 and the centrifugal force of the rotation of the rotor shaft 48, the low-temperature cooling oil is thrown out from the cooling medium outlet 42 to the end of the copper wire winding 44, which cools down the copper wire winding 44 and the rotor assembly at the end.

[0059] Combination Figure 2 and Figure 4The direct cooling process when the cooling medium is refrigerant is explained as follows: The inlet x and outlet z of the regulating valve group 7 are connected, and the cooling medium directly enters the third cooling channel 6. The third cooling channel 6, which is filled with low-temperature cooling medium, directly cools the copper wire winding 44 and the insulation layer 45 in the stator slot 43, ensuring that when the motor 4 continues to work at its highest power, the temperature of the copper wire winding 44 does not exceed the temperature limit of the insulation class.

[0060] Further, refer to Figure 2 The operating conditions of motor 4 include: a first condition where the driving speed of motor 4 is less than a preset speed threshold and the driving current is less than a preset current threshold; a second condition where the driving speed is less than the speed threshold and the driving current is greater than the current threshold; a third condition where the driving speed is greater than the speed threshold and the driving current is less than the current threshold; and a fourth condition where the driving speed is greater than the speed threshold and the driving current is greater than the current threshold. In the first condition, both copper losses and iron losses of motor 4 are low, and the heat generation of motor 4 is low. In the second condition, copper losses of motor 4 are high but iron losses are low; the heat generation of copper wire winding 44 is high, and the heat generation of stator core 47 is low. In the third condition, copper losses of motor 4 are low but iron losses are high; the heat generation of copper wire winding 44 is low, and the heat generation of stator core 47 is high. In the fourth condition, both copper losses and iron losses of motor 4 are high, and the heat generation of both copper wire winding 44 and stator core 47 is high. It should be noted that the speed threshold and current threshold need to be determined based on the rated speed and rated current of motor 4. Generally, the speed threshold is set to 70% to 80% of the rated speed, and the current threshold is set to 70% to 80% of the rated current.

[0061] Specifically, in the first operating condition, the regulating valve group 7 shuts off the passage to the heat exchanger 1 and the third cooling channel 6, while the first cooling valve 22, the first cooling pump 21, the second cooling valve 32, and the second cooling pump 31 are all open. At this time, the cooling medium only flows through the external cooling channel 5 and does not pass through the cooling system of the motor 4, and there is no low-temperature cooling medium inside the heat exchanger 1. The first cooling medium and the second cooling medium in the first cooling channel 2 and the second cooling channel 3 circulate within the motor 4, cooling the ends of the stator core 47 and the copper wire winding 44.

[0062] In the second operating condition, the regulating valve group 7 opens the passage to the heat exchanger 1 and the third cooling channel 6, while the first cooling valve 22 and the first cooling pump 21 are closed, and the second cooling valve 32 and the second cooling pump 31 are open. At this time, the cooling medium in the external cooling channel 5 enters through the inlet x of the regulating valve group 7, enters the third cooling channel 6 through the outlet z, and enters the heat exchanger 1 through the outlet y. After absorbing heat, it continues to return to the external cooling channel 5. The cooling medium in the third cooling channel 6 directly cools the copper wire winding 44 and the insulation layer 45 in the stator slot 43. In addition, the second cooling medium flows out from the cooling medium outlet 42 of the cooling medium flow path 41 and cools the end of the copper wire winding 44. The second cooling medium, which has absorbed the heat from the end of the copper wire winding 44, is drawn back to the heat exchanger 1 from the oil collector 411 by the second cooling pump 31 to exchange heat with the cooling medium. After cooling down, it returns to the cooling medium flow path 41.

[0063] In the third operating condition, the regulating valve group 7 opens the passage to the heat exchanger 1 and closes the passage to the third cooling channel 6. The first cooling valve 22 and the first cooling pump 21 are opened, while the second cooling valve 32 and the second cooling pump 31 are closed. At this time, the cooling medium in the external cooling channel 5 enters through the inlet x of the regulating valve group 7, enters the heat exchanger 1 through the outlet y, absorbs heat, and then returns to the external cooling channel 5. The first cooling medium flows through the motor housing flow path 46, directly cooling the motor housing and indirectly cooling the stator core 47. After exchanging heat with the motor housing, the first cooling medium is drawn back to the heat exchanger 1 by the first cooling pump 21, absorbs heat, and then returns to the motor housing flow path 46.

[0064] In the fourth operating condition, the regulating valve group 7 opens the passage to the heat exchanger 1 and the third cooling channel 6, and the first cooling valve 22, the first cooling pump 21, the second cooling valve 32, and the second cooling pump 31 are all open. At this time, the cooling medium in the external cooling channel 5 enters through the inlet x of the regulating valve group 7, enters the third cooling channel 6 through the outlet z, and enters the heat exchanger 1 through the outlet y. After absorbing heat, it continues to return to the external cooling channel 5. The cooling medium in the third cooling channel 6 directly cools the copper wire winding 44 and the insulation layer 45 in the stator slot 43. In addition, the second cooling medium flows out from the cooling medium outlet 42 of the cooling medium flow path 41 and cools the end of the copper wire winding 44. The second cooling medium, which has absorbed the heat from the end of the copper wire winding 44, is drawn back to the heat exchanger 1 from the oil collector 411 by the second cooling pump 31 to exchange heat with the cooling medium. After cooling down, it returns to the cooling medium flow path 41. The first cooling medium flows through the motor housing flow path 46, directly cooling the motor housing, and indirectly cooling the stator core 47 through heat conduction between the motor housing and the stator core 47. After exchanging heat with the motor housing, the first cooling medium is drawn back to the heat exchanger 1 by the first cooling pump 21, absorbs heat, and then returns to the motor housing flow path 46.

[0065] In this way, by cooperating with the regulating valve group 7, the first cooling pump 21, the first cooling valve 22, the second cooling pump 31 and the second cooling valve 32, cooling can be carried out in different areas, which facilitates precise temperature control and improves the cooling efficiency of the cooling system. In addition, it can also enable the motor 4 to start different cooling channels to execute different cooling strategies under different working conditions, thereby reducing energy consumption while ensuring the cooling of the motor 4.

[0066] Furthermore, the cooling system also includes a detection component, which is a temperature detection component located at the motor winding. This temperature detection component is connected to an external valve regulating component, which in turn is connected to a flow regulating valve. It should be understood that the motor winding is also known as the copper wire winding 44. Specifically, the temperature detection component can be a temperature sensor, and the external valve regulating component can be a drive motor or an adjusting screw capable of actuating the valve needle. The flow regulating valve can adjust its on / off state or flow rate based on the temperature at the motor winding, thereby controlling the flow rate of the cooling medium in the flow path and improving the cooling efficiency of the motor 4. It should be noted that the temperature detection component can also be located in other positions on the motor 4, such as inside the motor housing, at the rotor assembly, or at the motor end, preferably at the location where the temperature rises fastest or is highest, thus enabling timely cooling of the motor 4.

[0067] Further, refer to Figure 5 Motor 4 is an on-board motor, and the external cooling channel 5 is connected to the vehicle's passenger compartment cooling system and / or battery cooling system. The heat exchanger 1 is connected to the external cooling channel 5 in parallel with the passenger compartment cooling system and / or battery cooling system. The cooling medium passage and the outlet of the third cooling channel 6 are both connected to the passenger compartment cooling system and / or battery cooling system. In other words, the cooling system of motor 4 provided in this embodiment can be used to cool the on-board motor. When used for cooling the on-board motor, the refrigerant in the passenger compartment cooling system and / or battery cooling system can be used as the cooling medium. Connecting the cooling system of motor 4 to the passenger compartment cooling system and / or battery cooling system allows the motor 4 to share components such as the compressor and condenser of the passenger compartment air conditioning or battery cooling system during cooling, reducing additional piping and heat exchangers, lowering hardware costs and installation space. Furthermore, it eliminates the need for multiple circulation pumps, water tanks, etc., reducing system weight and improving overall vehicle energy efficiency. It should be noted that the external cooling channel 5 in this embodiment can be connected only to the passenger cabin cooling system to introduce the cooling medium more conveniently and quickly, or only to the battery cooling system to introduce a suitable amount of cooling medium, or it can be connected to both the passenger cabin cooling system and the battery cooling system at the same time to introduce a large amount of cooling medium, as long as the cooling medium can be introduced as needed.

[0068] Further, refer to Figure 5The external cooling channel 5 includes a compressor 51 and a condenser 52 connected in series, with the compressor 51 located upstream of the condenser 52. A fan 53 is also provided around the condenser 52. In the first operating condition, the switching valve 8 is closed, and the cooling medium flows through the passenger cabin cooling system and the battery cooling system, bypassing the motor cooling system. In the second, third, and fourth operating conditions, the switching valve 8 is open, and the cooling medium is compressed into a high-temperature, high-pressure gas by the compressor 51. After releasing heat in the condenser 52, it enters the expansion valve 9 for throttling and pressure reduction, forming a low-temperature, low-pressure medium. It should also be noted that this embodiment only schematically lists some components of the passenger cabin cooling system. Those skilled in the art can also add other related components according to actual needs, such as a liquid storage tank, a gas-liquid separator, and a reversing valve.

[0069] Example 2:

[0070] Based on the motor cooling system provided in the foregoing embodiments, this embodiment provides a vehicle cooling system.

[0071] The vehicle cooling system provided in this embodiment includes the motor cooling system described in Embodiment 1, as well as the passenger compartment cooling system and / or battery cooling system. The motor cooling system and the passenger compartment cooling system are connected via a heat exchanger in the motor cooling system. The battery cooling system and the passenger compartment cooling system are also connected via a heat exchanger.

[0072] The vehicle cooling system provided in this embodiment connects the motor cooling system with the passenger compartment cooling system and / or the battery cooling system. This allows the motor to share components such as the compressor and condenser of the passenger compartment air conditioning or battery cooling system when cooling, reducing additional piping and heat exchangers, thus lowering hardware costs and installation space. Furthermore, it eliminates the need for multiple circulation pumps and water tanks, reducing system weight and improving overall vehicle energy efficiency.

[0073] Example 3:

[0074] Based on the vehicle cooling system provided in the foregoing embodiments, this embodiment provides a vehicle including the vehicle cooling system as described in Embodiment 2.

[0075] The vehicle provided in this embodiment has higher energy efficiency, lower weight, and lower hardware cost due to the aforementioned vehicle cooling system.

[0076] Although the present invention has been illustrated and described with reference to certain preferred embodiments, those skilled in the art should understand that the above description is a further detailed explanation of the present invention in conjunction with specific embodiments, and should not be construed as limiting the specific implementation of the present invention to these descriptions. Those skilled in the art can make various changes in form and detail, including some simple deductions or substitutions, without departing from the spirit and scope of the present invention.

Claims

1. A cooling system for an electric motor, characterized in that, include: A heat exchanger is disposed outside the motor and communicates with an external cooling channel, through which the cooling medium in the external cooling channel flows. A first cooling channel is disposed between the motor housing and the heat exchanger, and a first cooling medium flowing through the first cooling channel exchanges heat with the cooling medium flowing through the heat exchanger. The second cooling channel is disposed between the cooling medium flow path inside the motor housing and the heat exchanger, and has a cooling medium outlet facing the rotor assembly of the motor. The second cooling medium flowing through the second cooling channel exchanges heat with the cooling medium flowing through the heat exchanger in the heat exchanger.

2. The cooling system for the motor as described in claim 1, characterized in that, in The heat exchanger includes a cooling medium passage, and a first cooling medium passage and a second cooling medium passage respectively disposed adjacent to the cooling medium passage; and The outlet of the external cooling channel is connected to the inlet of the cooling medium passage, and the outlet of the cooling medium passage leads to the outside of the heat exchanger. The upstream portion of the first cooling channel connects the outlet of the motor housing flow path inside the motor housing with the inlet of the first cooling medium passage, and the downstream portion connects the outlet of the first cooling medium passage with the inlet of the motor housing flow path. The first cooling medium from the motor housing flow path enters the inlet of the first cooling medium passage through the upstream portion of the first cooling channel, and re-enters the motor housing flow path from the outlet of the first cooling medium passage through the downstream portion of the first cooling channel. The upstream portion of the second cooling channel connects the outlet of the cooling medium flow path within the motor housing to the inlet of the second cooling medium passage; the downstream portion connects the outlet of the second cooling medium passage to the inlet of the cooling medium flow path. The second cooling medium from the cooling medium flow path enters the inlet of the second cooling medium passage via the upstream portion of the second cooling channel, and re-enters the cooling medium flow path from the outlet of the second cooling medium passage via the downstream portion of the second cooling channel. The cooling medium flow path has an oil collection port located inside the motor housing.

3. The cooling system for the motor as described in claim 2, characterized in that, Also includes: A third cooling channel is disposed within the stator slot of the motor and communicates with an external cooling channel. The cooling medium in the external cooling channel flows through the third cooling channel. The inlet of the third cooling channel is connected to the outlet of the external cooling channel, and the outlet is connected to the outside of the motor.

4. The cooling system for the motor as described in claim 3, characterized in that, in The external cooling channel is connected to the heat exchanger via a regulating valve assembly, which includes a three-way valve; wherein The inlet of the three-way valve is connected to the external cooling channel, and one outlet of the three-way valve is connected to the inlet of the cooling medium passage, while the other outlet is connected to the inlet of the third cooling channel; or The regulating valve assembly includes two check valves, the inlets of which are connected to the external cooling channel; the outlet of one check valve is connected to the inlet of the cooling medium passage; and the outlet of the other check valve is connected to the inlet of the third cooling channel. A flow regulating valve is also connected in series upstream of the inlet of the regulating valve group. The flow regulating valve is a switching valve and / or an expansion valve.

5. The cooling system for the motor as described in claim 4, characterized in that, The upstream portion of the first cooling channel is equipped with a first cooling pump, and the downstream portion is equipped with a first cooling valve; and The upstream portion of the second cooling channel is equipped with a second cooling pump, and the downstream portion is equipped with a second cooling valve.

6. The cooling system for the motor as described in claim 5, characterized in that, The operating conditions of the motor include a first condition in which the driving speed of the motor is less than a preset speed threshold and the driving current is less than a preset current threshold. The second operating condition is that the driving speed is less than the speed threshold and the driving current is greater than the current threshold; The third operating condition is where the driving speed is greater than the speed threshold and the driving current is less than the current threshold. And a fourth operating condition in which the driving speed is greater than the speed threshold and the driving current is greater than the current threshold; in Under the first operating condition, the regulating valve group shuts off the passage to the heat exchanger and the third cooling channel, and the first cooling valve, the first cooling pump, the second cooling valve and the second cooling pump are all turned on. In the second operating condition, the regulating valve group opens the passage to the heat exchanger and the third cooling channel, and the first cooling valve and the first cooling pump are closed, while the second cooling valve and the second cooling pump are open. In the third operating condition, the regulating valve group opens the passage to the heat exchanger and closes the passage to the third cooling channel, and the first cooling valve and the first cooling pump are opened, while the second cooling valve and the second cooling pump are closed. In the fourth operating condition, the regulating valve group opens the passage to the heat exchanger and the third cooling channel, and the first cooling valve, the first cooling pump, the second cooling valve and the second cooling pump are all turned on.

7. The cooling system for the motor as described in claim 6, characterized in that, in The second cooling channel is disposed within the rotor shaft of the motor, and the rotor shaft has a plurality of through holes in its circumferential direction serving as outlets for the cooling medium; the plurality of through holes penetrate the sidewall of the rotor shaft and extend along the radial direction of the rotor shaft and / or toward a first direction, wherein the first direction extends obliquely relative to the radial direction; or The second cooling channel is disposed inside the motor housing, extends along the inner wall of the motor housing, and has a cooling medium outlet facing the rotor assembly of the motor; and The cooling system also includes a detection component, which is a temperature detection component located at the winding of the motor, and is connected to an external valve regulating component; and The external valve regulating component is connected to the flow regulating valve.

8. The cooling system for the motor as described in claim 7, characterized in that, in The first cooling medium is coolant, the second cooling medium is cooling oil, and the cooling medium is refrigerant; and The motor is an on-board motor, and the external cooling channel is connected to the vehicle's passenger compartment cooling system and / or battery cooling system; wherein The heat exchanger is connected in parallel to the passenger cabin cooling system and / or battery cooling system to the external cooling channel, and the outlets of the cooling medium passage and the third cooling channel are both connected to the passenger cabin cooling system and / or battery cooling system; and The external cooling channel includes a compressor and a condenser connected in series, with the compressor located upstream of the condenser.

9. A vehicle cooling system, characterized in that, Including the cooling system of the motor as described in any one of claims 1-8, and A passenger cabin cooling system, wherein the motor cooling system is connected to the passenger cabin cooling system via a heat exchanger of the motor cooling system; and / or A battery cooling system, which is connected to the passenger cabin cooling system via the heat exchanger.

10. A vehicle, characterized in that, Includes the vehicle cooling system as described in claim 9.

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