Hybrid electric drive assembly, cooling system, control method and vehicle thereof

Abstract

The present invention discloses a hybrid electric drive assembly and its cooling system, control method and vehicle to solve the problem of low integration of hybrid transmissions. The hybrid electric drive assembly cooling system includes a first cooling circuit and a second cooling circuit. The first cooling circuit is used to cool the execution unit of the hybrid electric drive assembly; the second cooling circuit is used to cool the controller of the hybrid electric drive assembly; the first cooling circuit or the second cooling circuit is provided with a heat exchanger, and the heat exchanger is provided with a first medium channel and a second medium channel. The first medium channel is connected to the first cooling circuit, and the second medium channel is connected to the second cooling circuit. When the first cooling medium circulates in the first medium channel, it exchanges heat with the second cooling medium circulated in the second medium channel. The present invention not only meets the cooling requirements of the execution unit, but also improves the integration of the hybrid electric drive assembly cooling system, making the structure of the hybrid transmission more compact and improving the overall vehicle carrying capacity.

Description

Technical Field

[0001] The present invention belongs to the technical field of hybrid electric drive assemblies, and in particular relates to a hybrid electric drive assembly, a cooling system thereof, a control method and a vehicle. Background Art

[0002] The hybrid electric drive assembly includes a hybrid transmission, which is equipped with a generator and a drive motor. The generator and the drive motor drive the shaft gears to rotate. During the operation of the hybrid transmission, a large amount of heat is generated. Currently, the motor is cooled by cooling circulating water, and the gear cavity is cooled and lubricated by transmission oil. Two independent systems are required to meet the cooling needs of the motor and shaft gears. The shaft gears are cooled and lubricated with oil to maintain the formation of an oil film between the gears, reduce meshing noise, and improve transmission efficiency. There is sufficient oil lubrication between the bearing rollers and the raceway, which can increase the bearing life and reduce noise. The oil cooling and lubrication between the oil seal and the half shaft can avoid oil leakage caused by abnormal wear of the oil seal.

[0003] However, the current hybrid transmission uses a separate cooling system to cool the coolant of the hybrid transmission, which makes the integration of the hybrid transmission low. Summary of the Invention

[0004] To solve the above-mentioned technical problems, the present invention provides a hybrid electric drive assembly, a cooling system thereof, a control method and a vehicle, which not only meet the cooling requirements of the execution unit, but also improve the integration of the hybrid electric drive assembly cooling system, making the structure of the hybrid transmission more compact and improving the vehicle's carrying capacity.

[0005] The technical solution of the present invention is:

[0006] In one aspect, the present invention provides a hybrid electric drive assembly cooling system, comprising:

[0007] a first cooling circuit for circulating a first cooling medium to cool an execution unit of the hybrid electric drive assembly;

[0008] a second cooling circuit for circulating a second cooling medium to cool a controller of the hybrid electric drive assembly;

[0009] In which, the first cooling circuit or the second cooling circuit is provided with a heat exchanger, and the heat exchanger is provided with a first medium channel and a second medium channel. The first medium channel is connected to the first cooling circuit, and the second medium channel is connected to the second cooling circuit. When the first cooling medium flows in the first medium channel, heat exchange is performed with the second cooling medium flowing in the second medium channel.

[0010] In some embodiments, the execution unit includes one or more driving mechanisms and a transmission assembly connected to the driving mechanisms.

[0011] In some embodiments, the driving mechanism is a motor, and the first cooling circuit includes one or more motor cooling passages, wherein the motor cooling passages include a stator cooling passage and a rotor cooling passage that are arranged in parallel.

[0012] In some embodiments, there are two motor cooling passages, the stator cooling passages of the two motor cooling passages are connected in parallel, and the rotor cooling passages of the two motor cooling passages are connected in parallel.

[0013] In some embodiments, the hybrid electric drive assembly cooling system further includes a transmission component cooling passage, wherein the transmission component cooling passage is connected in series with the rotor cooling passage and is close to an outlet end of the rotor cooling passage.

[0014] In some embodiments, the first cooling circuit includes an oil storage mechanism, a first power mechanism, the one or more motor cooling passages, and a transmission assembly cooling passage connected by a pipeline;

[0015] In some embodiments, the hybrid electric drive assembly cooling system further includes:

[0016] The first housing assembly, the execution unit is installed in the first housing assembly, and the oil storage mechanism is arranged at the bottom of the first housing assembly.

[0017] In some embodiments, a fluid channel for circulating the first cooling medium is provided inside the first housing assembly, and the fluid channel is connected to the first cooling circuit.

[0018] In some embodiments, the first cooling circuit further includes a switching valve, and the switching valve, the oil storage mechanism, the one or more motor cooling passages, and the first medium channel of the heat exchanger are connected to connect the oil storage mechanism and the one or more motor cooling passages under a first temperature condition, and to connect the oil storage mechanism and the first medium channel of the heat exchanger under a second temperature condition.

[0019] In some embodiments, the switching valve is a thermostat or an electrically controlled valve, and the electrically controlled valve is electrically connected to the controller.

[0020] In some embodiments, the hybrid electric drive assembly cooling system further includes a second temperature sensor for detecting the temperature of the first cooling medium in the oil storage mechanism.

[0021] In some embodiments, the first cooling circuit further includes a switch valve, which is connected in series to the stator cooling passage and is close to an inlet end of the stator cooling passage.

[0022] In some embodiments, the hybrid electric drive assembly cooling system further includes a first temperature sensor for detecting the temperature of the stator of the motor, and the first temperature sensor and the switch valve are both electrically connected to the controller.

[0023] In some embodiments, the second cooling circuit includes a second power mechanism, a cooler, a cooling plate, and a second medium channel of the heat exchanger that are connected through a pipeline, and the cooling plate exchanges heat with the controller.

[0024] In a second aspect, the present invention provides a hybrid electric drive assembly, comprising a controller, an execution unit, and the aforementioned hybrid electric drive assembly cooling system.

[0025] In some embodiments, the hybrid electric drive assembly includes a second housing assembly, and the controller is installed in the second housing assembly.

[0026] In a third aspect, the present invention further provides a control method for the aforementioned hybrid electric drive assembly cooling system, comprising:

[0027] Acquiring the medium temperature of the first cooling medium in the oil storage mechanism;

[0028] When the medium temperature t is t<T1, the valve core position of the electronically controlled valve is controlled to connect the oil storage mechanism and the motor cooling passage; when the medium temperature t is t≥T2, the valve core position of the electronically controlled valve is controlled to connect the oil storage mechanism and the first medium channel of the heat exchanger, wherein T1 and T2 are both set temperatures, T1>T2.

[0029] In a fourth aspect, the present invention further provides a control method for the aforementioned hybrid electric drive assembly cooling system, comprising:

[0030] Get the temperature of the stator;

[0031] When the temperature t of the stator is t≥T0, the switch valve is controlled to open to connect the stator cooling passage; when the temperature t of the stator is t<T0, the switch valve is controlled to close to close the stator cooling passage.

[0032] In a fifth aspect, the present invention provides a hybrid vehicle comprising the aforementioned hybrid electric drive assembly.

[0033] The beneficial effects of the present invention include at least:

[0034] The present invention provides a hybrid electric drive assembly cooling system, which includes a first cooling circuit and a second cooling circuit. The first cooling circuit is used to circulate a first cooling medium to cool the execution unit of the hybrid electric drive assembly; the second cooling circuit is used to circulate a second cooling medium to cool the controller of the hybrid electric drive assembly; the controller is an MTCU controller, which is the sum of the motor controller and the hybrid box controller, that is, the sum of the TCU and the MCU. The first cooling circuit or the second cooling circuit is provided with a heat exchanger, and the heat exchanger is provided with a first medium channel and a second medium channel. The first medium channel is connected to the first cooling circuit, and the second medium channel is connected to the second cooling circuit. When the first cooling medium circulates in the first medium channel, it exchanges heat with the second cooling medium circulated in the second medium channel. The first cooling circuit is the cooling circuit of the execution unit of the hybrid electric drive assembly. In the second cooling circuit, the inlet temperature of the controller cooling water is about 60°C, and the outlet temperature of the controller cooling water is about 65°C. Therefore, the temperature of the cooling medium in the second cooling circuit does not exceed 65°C. The cooling medium in the second cooling circuit has a large cooling capacity relative to the execution unit of the hybrid electric drive assembly and can meet the inlet requirements of the first cooling circuit. Therefore, the second cooling circuit of the controller of the hybrid electric drive assembly can be used to cool the medium in the first cooling circuit of the execution unit of the hybrid electric drive assembly, which not only meets the cooling requirements of the execution unit, but also improves the integration of the hybrid electric drive assembly cooling system, makes the structure of the hybrid transmission more compact, and improves the vehicle's carryability. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 This is a schematic structural diagram of the hybrid electric drive assembly cooling system of Example 1.

[0036] Figure 2 This is a process step diagram of the control method of Example 2.

[0037] Figure 3 This is a process step diagram of the control method of Example 3.

[0038] Description of reference numerals:

[0039] 1-first cooling circuit; 11-heat exchanger; 12-oil storage mechanism; 13-first power mechanism; 14-on / off valve;

[0040] 2-second cooling circuit; 21-second power mechanism; 22-cooler; 23-cooling plate;

[0041] 3-switching valve; 4-controller; 5-rotor; 6-stator; 7-transmission assembly, 71-first bearing assembly, 72-second bearing assembly; 8-first temperature sensor, 9-second temperature sensor. DETAILED DESCRIPTION

[0042] In order to enable those skilled in the art to which this application belongs to understand this application more clearly, the technical solution of this application is described in detail below through specific embodiments in conjunction with the accompanying drawings.

[0043] Hybrid transmissions utilize the engine and motor in various power coupling modes, enabling pure electric drive, series drive (dual-motor systems), parallel drive, hybrid drive (dual-motor systems), engine-driven charging, energy recovery, and idle charging. Existing hybrid transmissions generally use a water-cooled motor solution, separating the motor cavity from the gear cavity. The motor cavity is cooled by circulating cooling water, while the gear cavity is lubricated by transmission oil.

[0044] This solution requires a separate motor housing, a cavity cast within it, and piping, increasing the complexity and overall weight of the transmission case. It also requires cooling water from the vehicle's cooling system to be routed into the piping and cavities within the motor housing, forming a circulating water circuit to remove heat from the motor. This consumes the vehicle's cooling capacity, increasing the load on the cooling system and making it more difficult to integrate the hybrid transmission into the vehicle. Furthermore, having two separate cooling systems to meet the cooling needs of the motor and bearings reduces overall integration.

[0045] In view of the deficiencies in the prior art and the above-mentioned related technologies, the present invention provides a hybrid electric drive assembly, a cooling system thereof, a control method and a vehicle.

[0046] Example 1

[0047] An embodiment of the present application provides a hybrid electric drive assembly cooling system, which can use the low-temperature cooling medium of the control unit of the hybrid electric drive assembly to cool the cooling medium of the execution unit, thereby improving the cooling effect of the execution unit; at the same time, the cooling circuits of the control unit and the execution unit are integrated into a design, which is more compact and saves space; and the present application adopts a cooling system to meet the cooling and lubrication of the motor and bearings, which is simple and reliable, and improves the integration of the system.

[0048] See also Figure 1The hybrid electric drive assembly cooling system provided in the embodiment of the present application includes a first cooling circuit 1 and a second cooling circuit 2. The first cooling circuit 1 is used to circulate a first cooling medium to cool the execution unit of the hybrid electric drive assembly; the second cooling circuit 2 is used to circulate a second cooling medium to cool the controller 4 of the hybrid electric drive assembly; the controller 4 is an MTCU controller 4, which is the sum of the motor controller and the hybrid box controller, that is, the sum of the TCU and the MCU. Among them, the first cooling circuit 1 or the second cooling circuit 2 is provided with a heat exchanger 11, and the heat exchanger 11 is provided with a first medium channel and a second medium channel. The first medium channel is connected to the first cooling circuit 1, and the second medium channel is connected to the second cooling circuit 2. When the first cooling medium circulates in the first medium channel, it exchanges heat with the second cooling medium circulated in the second medium channel.

[0049] The first cooling circuit 1 is the cooling circuit of the controller 4 of the hybrid electric drive assembly. The inlet temperature of the cooling water of the controller 4 of the hybrid electric drive assembly is about 60°C, and the outlet temperature of the controller cooling water is about 65°C. Therefore, the temperature of the cooling medium in the second cooling circuit 1 does not exceed 65°C. The cooling medium in the second cooling circuit has a large cooling capacity relative to the execution unit of the hybrid electric drive assembly and can meet the inlet requirements of the first cooling circuit. Therefore, the first cooling circuit 1 of the controller 4 of the hybrid electric drive assembly can be used to cool the medium in the second cooling circuit 2 of the execution unit of the hybrid electric drive assembly, which not only meets the cooling requirements of the execution unit, but also improves the integration of the hybrid electric drive assembly cooling system, makes the structure of the hybrid transmission more compact, and improves the vehicle's carrying capacity.

[0050] In some embodiments, the execution unit includes one or more driving mechanisms and a transmission assembly 7 connected to the driving mechanisms, so that power transmission between the driving mechanisms and the transmission assembly 7 can be achieved.

[0051] Specifically, the driving mechanism is a motor, and the first cooling circuit 1 includes more than one motor cooling passage, that is, the first cooling circuit 1 includes multiple motor cooling passages, for example, the first cooling circuit 1 includes two motor cooling passages. Of course, the first cooling circuit 1 can also be provided with other numbers of motor cooling passages as needed; the motor cooling passage includes a stator cooling passage and a rotor cooling passage that are connected in parallel, and the stator cooling passage and the rotor cooling passage are connected in parallel. That is, the motor cooling passage includes a stator cooling passage for cooling the stator 6 of the motor, and a rotor cooling passage for cooling the rotor 5 of the motor; when the motor is not working, the temperature of the stator 6 is low and there is no cooling requirement; during the operation of the motor, the stator winding generates a large amount of heat due to electromagnetic induction. When the operating temperature of the stator 6 is high, the stator needs to be cooled. The rotation of the motor rotor generates heat and conducts part of the heat of the stator winding. Therefore, the cooling requirements of the stator and rotor are different during the operation of the motor, and the preliminary cooling requirement ratio can be determined through simulation. The cooling passages of the stator 6 and rotor 5 of the motor are arranged in parallel so that the cooling of the stator 6 and rotor 5 of the motor does not affect each other, and the stator cooling passage can be controlled separately according to the cooling demand; for example, when the operating temperature of the stator 6 is low, the stator cooling passage can be closed and no cooling is performed; when the operating temperature of the stator 6 is high, the stator cooling passage can be opened to cool the stator 6; the parallel connection of the stator cooling passage and the rotor cooling passage can also be called a parallel setting, which can meet the cooling demand of the stator 6 of the motor and provide the motor with a suitable operating temperature, while not generating excess cooling flow of the first medium and not causing energy waste. The stator cooling passage is connected to a cooling nozzle, which sprays the first cooling medium onto the stator 6 to cool the stator 6. By adjusting the size of the stator cooling channel and the rotor cooling channel, the flow ratio distribution of the first cooling medium entering the stator cooling channel and the rotor cooling channel can be adjusted.

[0052] Preferably, two motor cooling pathways are provided, corresponding to the generator and drive motor of a current hybrid electric drive assembly. The two motor cooling pathways are the generator cooling pathway and the drive motor cooling pathway. The stator cooling pathways of the two motor cooling pathways are connected in parallel, meaning the stator cooling pathways of the generator and drive motor are connected in parallel or arranged in parallel. The rotor cooling pathways of the two motor cooling pathways are connected in parallel, meaning the rotor cooling pathway of the generator is connected in parallel or in parallel with the rotor cooling pathway of the drive motor. This results in the stator cooling pathway of the generator, the rotor cooling pathway of the generator, the stator cooling pathway of the drive motor, and the rotor cooling pathway of the drive motor all being connected in parallel. In other embodiments, the number of motor cooling pathways can be adjusted based on the number of motors in the hybrid electric drive assembly, such as three or four motor cooling pathways. Regardless of the number of motor cooling pathways provided, the multiple stator cooling pathways and the multiple rotor cooling pathways corresponding to the multiple motor cooling pathways are all connected in parallel.

[0053] In some embodiments, the hybrid electric drive assembly cooling system further includes a transmission assembly cooling passageway, which is serially connected to the rotor cooling passageway and located near the rotor cooling passageway's outlet. The transmission assembly cooling passageway is used to cool the drive mechanism, i.e., the transmission assembly 7 of the motor. Specifically, when two motor cooling passageways are provided, the transmission assembly 7 includes a first bearing assembly 71 and a second bearing assembly 72 for supporting different rotating shafts. For example, the first bearing assembly 71 may include the motor rotor bearing and planetary gear bearings, while the second bearing assembly 72 may include the motor rotor bearing and input shaft bearings, which may be ball bearings. The transmission assembly cooling passageway is serially connected to the rotor cooling passageway and located near the rotor cooling passageway's outlet. This means that oil enters the rotor cooling passageway first. The rotor 5 is provided with radially extending liquid holes connected to the rotor cooling passageway. The first cooling medium is ejected through the liquid holes in the rotor 5 to the stator 6 and transmission assembly 7 for cooling, and then the oil falls into the oil reservoir 12. More specifically, the generator's rotor cooling passage is connected in series with the cooling passage of its corresponding gear mechanism, and the drive motor's rotor cooling passage is connected in series with the cooling passage of its corresponding gear mechanism. If there are more than two motors, the rotor cooling passage of each motor is connected in series with the cooling passage of its corresponding gear mechanism. The serial connection of the transmission assembly cooling passage and the rotor cooling passage allows the motor and gear cavities to utilize a common oil system. Specifically, the motor cavity is cooled by cooled transmission fluid, and the gear cavity is also cooled by cooled transmission fluid. Compared to a structure in which the motor and gear cavities are separated, with the motor cavity cooled by circulating cooling water and the gear cavity lubricated by transmission fluid, this improves the integration of the hybrid transmission and eliminates the need for a separate motor housing, simplifying the cooling system and component types.

[0054] In some embodiments, the first cooling circuit 1 includes an oil storage mechanism 12, a first power mechanism 13, one or more motor cooling passages and a transmission component cooling passage that can be connected through pipelines; the oil storage mechanism 12 is used to store oil for lubrication and cooling, that is, the first cooling medium is oil; the first power mechanism 13 is used to drive the first cooling medium, that is, oil, to flow in the first cooling circuit 1 to actively take away the heat generated by the execution unit. The first power mechanism 13 can be an electronic oil pump or a mechanical oil pump. When the first power mechanism 13 uses an electronic oil pump, it is electrically connected to the controller 4, and the speed of the electronic oil pump can be controlled by the controller 4 to match the cooling requirements of the motor.

[0055] In some embodiments, the hybrid electric drive assembly cooling system further includes a first housing assembly, in which the actuator, i.e., the motor, is mounted. An oil reservoir 12 is disposed at the bottom of the first housing assembly. The bottom of the first housing assembly forms an oil pan for storing oil, serving as the aforementioned oil reservoir 12.

[0056] Based on the above embodiment, a fluid channel for circulating the first cooling medium is provided within the first housing assembly, and the fluid channel is connected to the first cooling circuit 1. Compared to the prior art motor water cooling, there is no need to install pipes and cavities in the motor housing to form a complex design of a circulating water circuit. Therefore, this application is simpler and more reliable, and the cooling system is more integrated.

[0057] In some embodiments, the first cooling circuit 1 may further include a switching valve 3, which connects the switching valve 3, the oil storage mechanism 12, one or more motor cooling passages, and the first medium channel of the heat exchanger 11 to connect the oil storage mechanism 12 and one or more motor cooling passages under a first temperature condition, and to connect the oil storage mechanism 12 and the first medium channel of the heat exchanger 11 under a second temperature condition, so as to open two different fluid channels. The switching valve 3 can switch between different flow channels of the first cooling medium according to temperature changes of the first cooling medium. In some embodiments, the opening temperatures of the two fluid channels are respectively a first set temperature T1 and a second set temperature T2. The first temperature condition mentioned above can be that the temperature t of the oil in the oil storage mechanism 12, i.e., the oil pan, is lower than the first set temperature T1. For example, the first set temperature T1 is 60°C, i.e., the temperature t of the first cooling medium is less than 60°C. The second temperature condition can be that the temperature of the oil in the oil storage mechanism 12, i.e., the oil pan, is not lower than the second set temperature T2. For example, the second set temperature is 0°C, i.e., the temperature t of the first cooling medium is ≥ 0°C. Specifically, when the temperature of the first cooling medium in the oil pan is lower than 0°C, i.e., when the temperature t of the first cooling medium is less than 0°C, the temperature of the oil in the oil pan is relatively low, which can meet the cooling requirements of the motor cooling passage. There is no need to perform heat exchange between the first cooling medium in the oil pan, i.e., the oil, and the low-temperature second cooling medium in the second cooling circuit 2. This reduces the burden on the second cooling circuit 2 for cooling the controller 4 of the hybrid electric drive assembly, and ensures that the controller 4 operates at an appropriate temperature. , while reducing the workload of the first power mechanism 13, which is now in a small circulation mode; when the oil temperature of the first cooling medium in the oil pan is not lower than the second set temperature T2, for example, when t≥60°C, the oil temperature is high and it is difficult to meet the cooling demand of the motor cooling passage in the first cooling circuit 1, so that the first medium channel of the heat exchanger 11 is connected to the first cooling circuit 1, the second cooling medium and the first cooling medium can exchange heat in the heat exchanger 11, and the temperature of the first cooling medium in the first cooling circuit 1 is reduced to meet the cooling demand of the motor cooling passage for the motor, thereby improving the system. Efficiency, at this time it is in the large circulation mode; the oil temperature of the oil storage mechanism 12 is not lower than the first set temperature T1 and lower than the second set temperature T2, for example, when 0℃≤t<60℃, the switching valve 3 connects the oil storage mechanism 12 and the motor cooling passage at the same time as connecting the oil storage mechanism 12 and the first medium channel of the heat exchanger 11, that is, the thermostat 3 is partially opened, part of the oil flows directly from the oil storage mechanism 12 into the motor cooling passage, and part of the oil flows from the oil storage mechanism 12 into the first medium channel of the heat exchanger 11 and then into the motor cooling passage. At this time, it is in the parallel mode of large circulation and small circulation.Because oil viscosity increases dramatically at low temperatures, the flow of low-temperature oil through the heat exchanger 11 and into the motor cooling passage creates significant backpressure in the upstream oil circuit, placing a significant workload on the first power mechanism 13. In severe cases, this can even cause the first power mechanism 13 to stop operating, resulting in damage to the first power mechanism 13 or other electronic components. The configuration of the switching valve 3 effectively reduces the power demand of the first power mechanism 13, and to a certain extent, reduces its cost and size. The aforementioned configuration of the switching valve 3 enables switching between a large and small circulation system, simultaneously meeting the cooling needs of the motor in the first cooling circuit 1 and the controller 4 in the second cooling circuit 2. The switching valve 3 is a valve in the vehicle that controls the flow path of the cooling medium. The switching valve 3 can be a thermostat or an electrically controlled valve electrically connected to the controller. The thermostat automatically adjusts the flow rate into the heat exchanger 11 based on the temperature of the first cooling medium, thereby reducing the temperature of the first cooling medium entering the motor cooling passage and saving energy. A thermostat is an automatic temperature control device, typically containing a temperature-sensing component. It uses expansion or contraction to open and close the flow of the first coolant. Specifically, it automatically adjusts the flow rate entering the heat exchanger 11 based on the temperature of the first coolant, altering the circulation range of the first coolant and thus adjusting the cooling system's heat dissipation capacity. A wax-type thermostat can be used, in which the paraffin wax within it controls the coolant's circulation pattern through thermal expansion and contraction. For more detailed information about the thermostat, please refer to the prior art; the detailed structure is not described in detail in this embodiment. The thermostat can be integrated into the first housing assembly, improving the integration of the hybrid transmission. When the switching valve 3 is an electrically controlled valve, an electrically controlled three-way valve can be used, enabling switching between two fluid channels and controlling the opening size under the control of a controller. Furthermore, a second temperature sensor 9 can be provided to detect the temperature of the first coolant, or the oil, within the oil reservoir 12. This temperature can be used to monitor the oil temperature in the oil reservoir 12 and control the speed of the drive mechanism based on this temperature.

[0058] In some embodiments, the first cooling circuit 1 may further include an on-off valve 14, which is connected in series to the stator cooling passage and is located near the inlet of the stator cooling passage to enable the stator cooling passage to be opened or closed. When the stator 6 does not need to be cooled, the on-off valve 14 is closed so that oil does not enter the stator cooling passage. The oil is only used for cooling and lubricating the rotor cooling passage and the transmission assembly 7, thereby improving the cooling and lubrication effect. When the motor is provided with multiple stators, multiple stator cooling passages are provided, and multiple stator cooling passages are connected in parallel, the on-off valve 14 is connected to the inlet of each stator cooling passage, that is, the on-off valve is provided upstream of the main passage of the stator cooling passage, so that one on-off valve 14 can simultaneously control the opening and closing of multiple stator cooling passages. Compared with providing one on-off valve 14 for each stator cooling passage, the structure of the present application is simpler and can achieve the opening or closing of the stator cooling passage.

[0059] Based on the above embodiment, the hybrid electric drive assembly cooling system further includes a first temperature sensor 8 for detecting the temperature of the motor's stator 6. The first temperature sensor 8 and the on-off valve 14 are both electrically connected to the controller 4. Based on the detection result of the first temperature sensor 8, the controller 4 determines whether the motor's stator 6 needs to be cooled. If the first temperature sensor 8 detects that the stator 6 temperature is lower than a stator set value T0, for example, 80°C is used as the stator set value, although other temperatures, such as 70°C, can also be set as needed, the controller 4 determines that the motor's stator 6 does not need to be cooled. The controller 4 issues a command to close the on-off valve 14, disconnecting the stator cooling passage and preventing oil from entering the stator cooling passage. If the first temperature sensor 8 detects that the stator 6 temperature is not lower than the stator set value T0, the controller 4 determines that the motor's stator 6 needs to be cooled. The controller 4 issues a command to open the on-off valve 14, connecting the stator cooling passage and allowing oil to enter the stator cooling passage to cool the motor's stator 6. At this time, the switch valve 14 can use a switch solenoid valve, which is electrically connected to the controller 4. The controller 4 can control whether the switch solenoid valve is energized or not energized to open or close, and execute the instructions of the controller 4 to allow the oil to enter or not enter the stator cooling passage, thereby achieving precise real-time control.

[0060] In some embodiments, the second cooling circuit 2 may include a second power mechanism 21, a cooler 22, a cooling plate 23, and a second medium channel of the heat exchanger 11, all connected by pipelines. The cooling plate 23 exchanges heat with the controller 4. The second power mechanism 21 may be a water pump, mounted on the engine via a bracket, to circulate the second cooling medium in the second cooling circuit 2. The cooler 22 may be the MTCU low-temperature cooler 22 of the MTCU, located in the vehicle front-end module. The cooler 22 is a common component used to cool the controller 4, used to reduce the water temperature when the controller 4 is operating under high load. The details of the cooler 22 can be referred to the specific disclosures in the prior art, and the specific structure of the cooler 22 is not limited in this application. The second cooling medium can be cooling water. Here, the heat exchanger 11 may be an oil-water heat exchanger, which is commonly used in hybrid transmissions. The details of the heat exchanger 11 can be referred to the specific disclosures in the prior art, and the specific structure of the heat exchanger 11 is not limited. In the second cooling circuit 2, circulating cooling water sequentially passes through the second power structure 21, cooler 22, cooling plate 23, and heat exchanger 11 before returning to the second power structure 21, forming a loop. In some embodiments, the second cooling circuit may further include a water storage mechanism connected to the second medium channel of the second power structure 21 and the heat exchanger 11. The water storage mechanism may be a water tank fixed to the vehicle frame.

[0061] The controller 4 can be a separately set control chip, or an existing controller 4 in the whole vehicle can be used. In this embodiment, the controller 4 uses the MTCU controller 4 of the hybrid transmission. The MTCU controller 4 is a hybrid transmission controller 4. The connected and controlled electrical equipment includes: a drive motor, a generator, a switch valve 14, a first power mechanism 13, a first temperature sensor 8, and a second temperature sensor 9. The stator cooling passage is controlled by the switch valve 14 to achieve precise control of the stator cooling passage at different oil temperatures.

[0062] Taking the stator setting value T0 as 80°C as an example, the first setting temperature T1 is 60°C, and the second setting temperature T2 is 0°C, the working principle of the hybrid electric drive assembly cooling system provided in the embodiment of the present application is as follows:

[0063] 1. In the hybrid electric drive assembly cooling system provided in the present application, when the oil temperature t in the oil storage mechanism 12, that is, the oil pan, is less than 0°C, the flow path of the oil in the oil storage mechanism 12, that is, the oil pan, is: the first power mechanism 13, the thermostat 3, and the motor cooling passage, that is, the small circulation; when the oil temperature in the oil pan t≥60°C, the flow path of the oil in the oil storage mechanism 12, that is, the oil pan, is: the first power structure, the thermostat 3, the heat exchanger 11, and the motor cooling passage, that is, the large circulation; when the oil temperature in the oil storage mechanism 12 is 0°C≤t<60°C, the oil flow path is two, one is the first power mechanism 13, the thermostat 3, and the motor cooling passage, and the other is the first power mechanism 13, the thermostat 3, the heat exchanger 11, and the motor cooling passage.

[0064] 2. In the hybrid electric drive assembly cooling system provided in this application, cooling oil continuously enters the cooling channel of the rotor 5, enters the liquid hole of the rotor through the rotor cooling channel, and is thrown to the transmission assembly 7 to actively lubricate the bearing assembly of the transmission assembly 7; when the temperature t of the motor stator 6 is less than 80°C, the controller 4 determines that the motor stator 6 does not need to be cooled, the controller 4 issues a command, the switch valve 14 is closed, the stator cooling passage is disconnected, and the oil cannot enter the stator cooling passage. When the temperature t of the motor stator 6 is greater than or equal to 80°C, the controller 4 determines that the motor stator 6 needs to be cooled, the controller 4 issues a command, the switch valve 14 is opened, the stator cooling passage is connected, and oil enters the stator cooling passage to cool the stator 6 of the motor.

[0065] In summary, in the hybrid electric drive assembly cooling system provided by the present application, the first cooling circuit 1 for cooling the drive mechanism (motor) and the transmission component 7 (bearing component, such as planetary gear bearing, input shaft bearing) and the second cooling circuit 2 of the MTCU controller 4 perform heat exchange through the oil-water heat exchanger 11. The low temperature characteristic of the cooling circulating water of the MTCU controller 4 is utilized to cool the oil in the first cooling circuit 1, and then meet the cooling requirements of the drive mechanism and the transmission component 7, thereby improving the integration of the overall cooling system, making the hybrid transmission more compact, and improving the vehicle's loadability; the drive mechanism and the shaft gear adopt a set of cooling systems, that is, the motor cavity adopts cooled transmission oil for cooling, and the gear cavity is also cooled by transmission oil. The above-mentioned first cooling circuit 1 is integrated on the first housing assembly, thereby improving the integration of the hybrid electric drive assembly cooling system, and the structure is compact and space-saving; the hybrid electric drive assembly cooling system provided by the present application can also be used as a lubrication system to actively lubricate the rotor of the motor and the transmission component 7, thereby realizing the integration of lubrication and cooling of the rotor of the motor and the transmission component 7.

[0066] Example 2

[0067] Based on the same inventive concept as Example 1, this embodiment of the present application provides a control method, which is applied to the hybrid electric drive assembly cooling system of Example 1. The control method can realize switching between three working modes: large cycle, small cycle, and large and small cycles in parallel to ensure the cooling requirements of the hybrid cooling control system; and the control method is simple and easy to implement.

[0068] See also Figure 2 , the control method provided in the embodiment of the present application includes:

[0069] S11, obtaining the medium temperature of the first cooling medium in the oil storage mechanism;

[0070] The controller obtains the first cooling medium (oil) temperature of the oil storage mechanism 12 from the second temperature sensor 9, and determines whether the oil needs to be heat exchanged with the heat exchanger 11 based on the oil temperature. When the oil temperature is high, the cooling capacity of the oil cannot meet the demand. The oil temperature can be lowered and the cooling capacity of the oil can be improved by heat exchange with the heat exchanger 11. When the oil temperature is low, the oil can meet the cooling demand and can meet the cooling and lubrication needs of the motor and the transmission components without heat exchange with the heat exchanger 11.

[0071] S12. When the medium temperature t is t<T1, the valve core position of the electronically controlled valve is controlled to connect the oil storage mechanism and the motor cooling passage; when the medium temperature t is t≥T2, the valve core position of the electronically controlled valve is controlled to connect the oil storage mechanism and the first medium channel of the heat exchanger, wherein T1 and T2 are both set temperatures, and T1>T2.

[0072] When the oil temperature is at a first temperature condition, the valve core position of the electronically controlled valve is controlled to connect the oil storage mechanism 12 with the motor cooling passage; when the oil temperature is at a second temperature condition, the valve core position of the electronically controlled valve is controlled to connect the oil storage mechanism 12 with the heat exchange channel of the heat exchanger 11. The above-mentioned first temperature condition is that the oil temperature t is lower than the first set temperature T1, and the above-mentioned second temperature condition is that the oil temperature t in the oil storage mechanism 8 is not lower than the second set temperature T2. Specifically, the first set temperature T1 can be 60°C, and the second set temperature T2 can be 0°C. Taking T1 as 60°C and T2 as 0°C as an example: when the oil temperature t is less than 0°C, the valve core position of the electric control valve is controlled so that the oil storage mechanism 12 is connected to the motor cooling passage, and the small circulation mode is turned on; when the oil temperature t is greater than or equal to 60°C, the valve core position of the electric control valve is controlled so that the oil storage mechanism 12 is connected to the heat exchange channel of the heat exchanger 11, and the large circulation mode is turned on; when the oil temperature is 0°C≤t<60°C, the valve core position of the electric control valve is controlled so that the oil storage mechanism is connected to the motor cooling passage, and the oil storage mechanism 12 is connected to the heat exchange channel of the heat exchanger 11, and the large and small circulation parallel mode is turned on.

[0073] The control method of this embodiment is applied to the hybrid electric drive assembly cooling system of the above-mentioned embodiment 1. Specifically, the control method is stored in the controller of the hybrid electric drive assembly cooling system in the form of a computer program. The controller obtains the oil temperature of the oil storage mechanism and controls the oil storage mechanism to be connected or closed to the motor cooling cooling passage, and the oil storage mechanism to be connected or closed to the first medium channel of the heat exchanger according to the oil temperature.

[0074] In summary, the control method provided in the embodiment of the present application cooperates with the aforementioned hybrid electric drive assembly cooling system to switch between three working modes: large cycle, small cycle, and large and small cycles in parallel to ensure the cooling requirements of the hybrid cooling control system; and the control method is simple and easy to implement.

[0075] Example 3

[0076] Based on the same inventive concept as that of Example 1, an embodiment of the present application provides a control method, which is applied to Example 1. The control method controls the opening or closing of the stator cooling passage to meet the cooling requirements of the motor stator and avoid energy waste.

[0077] See also Figure 3 , the control method provided in the embodiment of the present application includes:

[0078] S21, obtaining the temperature of the stator;

[0079] When the operating temperature of the stator 6 of the motor is low, the stator cooling passage can be closed and no cooling is performed. When the operating temperature of the stator 6 is high, the stator cooling passage can be opened to cool the stator 6. This can meet the cooling needs of the stator 6 of the motor and provide the motor with a suitable operating temperature. At the same time, no excess oil cooling flow will be generated and no energy will be wasted. In summary, the temperature of the stator 6 determines whether the stator cooling passage is open.

[0080] S22. When the temperature t of the stator is t≥T0, the switch valve is controlled to open so that the stator cooling passage is conductive; when the temperature t of the stator is t<T0, the switch valve is controlled to close so that the stator cooling passage is closed.

[0081] T0 can be 80°C, or other values depending on actual needs. If the temperature t of the motor's stator 6 is t<T0, the oil does not enter the stator cooling passage. Instead, the oil enters the rotor cooling passage to cool the motor's rotor. After the rotor is cooled, the cooling medium is ejected from the rotor's liquid holes, with some of the oil falling into the oil pan and some of the oil lubricating and cooling the transmission components. The oil after lubricating and cooling the transmission components also falls into the oil pan. If the temperature t of the motor's stator 6 is ≥T0, the on-off valve 14 opens, the stator cooling passage is open, and the oil enters the stator cooling passage to cool the motor's stator.

[0082] The control method of this embodiment is applied to the hybrid electric drive assembly cooling system of the above-mentioned embodiment 1. Specifically, the control method is stored in the controller of the hybrid electric drive assembly cooling system in the form of a computer program. The controller obtains the temperature of the stator and, based on program judgment, controls the opening and closing of the stator cooling passage according to the comparison result of the stator temperature and T0, and issues corresponding control instructions to the switch valve to activate the switch valve to realize the conduction or closing of the stator cooling passage.

[0083] In summary, the control method provided in the embodiment of the present application cooperates with the aforementioned hybrid electric drive assembly cooling system to control the conduction or closing of the stator cooling passage, thereby meeting the cooling requirements of the motor stator and avoiding energy waste.

[0084] Example 4 is based on the same inventive concept as Example 1. This embodiment of the present application provides a hybrid electric drive assembly that can ensure the cooling requirements of the MTCU controller and the execution unit (motor and transmission components), while improving the integration of the hybrid electric drive assembly.

[0085] For the sake of brief description, for matters not mentioned in this embodiment, please refer to the first embodiment.

[0086] The hybrid electric drive assembly includes a controller 4 , an execution unit, and the hybrid electric drive assembly cooling system in the first embodiment.

[0087] Specifically, the hybrid electric drive assembly includes a second housing assembly, the controller 4 is installed in the second housing assembly, the second housing assembly is connected to the first housing assembly, and the second housing assembly is arranged above the first housing assembly.

[0088] In summary, in the hybrid electric drive assembly provided by the present application, the first cooling circuit 1 and the second cooling circuit 2 are respectively integrated on the first housing assembly and the second housing assembly. The cooling system has a high degree of integration, a compact structure, saves space, and improves the vehicle's carrying capacity.

[0089] Example 5

[0090] Based on the same inventive concept as Example 4, this embodiment of the present application provides a hybrid vehicle that can ensure the cooling requirements of the MTCU controller and the execution unit (motor and shaft gear), while improving the integration of the hybrid electric drive assembly.

[0091] For the sake of brief description, for matters not mentioned in this embodiment, please refer to the fourth embodiment.

[0092] The hybrid vehicle provided by the embodiment of the present application includes the hybrid electric drive assembly of the fourth embodiment.

[0093] In summary, the hybrid vehicle provided in this application has a high degree of integration of the hybrid box, a compact structure, saves space, and improves the overall vehicle's carrying capacity.

[0094] Although the preferred embodiments of the present application have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present application.

[0095] Obviously, those skilled in the art may make various changes and modifications to this application without departing from the spirit and scope of this application. Thus, if these modifications and variations of this application fall within the scope of the claims of this application and their equivalents, this application is intended to include these modifications and variations.

Claims

1. A hybrid electric drive assembly cooling system, characterized in that: include: a first cooling circuit for circulating a first cooling medium to cool an actuator of the hybrid electric drive assembly; the actuator comprising one or more motors and a transmission assembly connected thereto; the first cooling circuit comprising an on-off valve and one or more motor cooling passages, the motor cooling passages comprising a stator cooling passage and a rotor cooling passage arranged in parallel; the on-off valve being connected in series to the stator cooling passage and being close to an inlet end of the stator cooling passage, so that when the stator temperature t≥T0, the on-off valve is opened, thereby conducting the stator cooling passage; and when the stator temperature t<T0, the on-off valve is closed, thereby closing the stator cooling passage, thereby achieving precise on-off control of the stator cooling passage at different oil temperatures; the rotor cooling passage is connected in series to the transmission assembly cooling passage, and the transmission assembly cooling passage is close to an outlet end of the rotor cooling passage; a second cooling circuit for circulating a second cooling medium to cool a controller of the hybrid electric drive assembly; In which, the first cooling circuit or the second cooling circuit is provided with a heat exchanger, and the heat exchanger is provided with a first medium channel and a second medium channel. The first medium channel is connected to the first cooling circuit, and the second medium channel is connected to the second cooling circuit. When the first cooling medium flows in the first medium channel, heat exchange is performed with the second cooling medium flowing in the second medium channel.

2. The hybrid electric drive assembly cooling system according to claim 1, characterized in that: There are two motor cooling passages, the stator cooling passages of the two motor cooling passages are connected in parallel, and the rotor cooling passages of the two motor cooling passages are connected in parallel.

3. The hybrid electric drive assembly cooling system according to claim 1, characterized in that: The first cooling circuit includes an oil storage mechanism, a first power mechanism, the one or more motor cooling passages and the transmission component cooling passage, which are connected through pipelines.

4. The hybrid electric drive assembly cooling system according to claim 3, characterized in that: The hybrid electric drive assembly cooling system further includes: The first housing assembly, the execution unit is installed in the first housing assembly, and the oil storage mechanism is arranged at the bottom of the first housing assembly.

5. The hybrid electric drive assembly cooling system according to claim 4, characterized in that: A fluid channel for circulating a first cooling medium is provided inside the first housing assembly, and the fluid channel is connected to the first cooling circuit.

6. The hybrid electric drive assembly cooling system according to claim 3, characterized in that: The first cooling circuit also includes a switching valve, and the switching valve, the oil storage mechanism, the one or more motor cooling passages and the first medium channel of the heat exchanger are connected to connect the oil storage mechanism and the one or more motor cooling passages under a first temperature condition and to connect the oil storage mechanism and the first medium channel of the heat exchanger under a second temperature condition.

7. The hybrid electric drive assembly cooling system according to claim 6, characterized in that: The switching valve is a thermostat or an electrically controlled valve, and the electrically controlled valve is electrically connected to the controller.

8. The hybrid electric drive assembly cooling system according to claim 7, characterized in that: The hybrid electric drive assembly cooling system further includes a second temperature sensor for detecting the temperature of the first cooling medium in the oil storage mechanism.

9. The hybrid electric drive assembly cooling system according to claim 1, characterized in that: The hybrid electric drive assembly cooling system further includes a first temperature sensor for detecting the temperature of the stator of the motor. The first temperature sensor and the switch valve are both electrically connected to the controller.

10. The hybrid electric drive assembly cooling system according to any one of claims 1 to 9, characterized in that: The second cooling circuit includes a second power mechanism, a cooler, a cooling plate, and a second medium channel of the heat exchanger, which are connected through a pipeline. The cooling plate exchanges heat with the controller.

11. A control method for a hybrid electric drive assembly cooling system according to claim 7 or 8, characterized in that: include: Acquiring the medium temperature of the first cooling medium in the oil storage mechanism; When the medium temperature t is t<T1, controlling the valve core position of the electronically controlled valve to connect the oil storage mechanism and the motor cooling passage; When the medium temperature t is t≥T2, the valve core position of the electric control valve is controlled to connect the oil storage mechanism and the first medium channel of the heat exchanger, wherein T1 and T2 are both set temperatures, and T1>T2.

12. A control method for a hybrid electric drive assembly cooling system according to claim 1 or 9, characterized in that: include: Get the temperature of the stator; When the temperature t of the stator is t≥T0, the switch valve is controlled to open so that the stator cooling passage is conductive; When the temperature t of the stator is t<T0, the switch valve is controlled to close so that the stator cooling passage is closed.

13. A hybrid electric drive assembly, characterized in that: The hybrid electric drive assembly cooling system comprises a controller, an execution unit and the cooling system of any one of claims 1 to 10.

14. The hybrid electric drive assembly according to claim 13, characterized in that: The hybrid electric drive assembly includes a second housing assembly, and the controller is installed in the second housing assembly.

15. A hybrid vehicle, characterized in that: Comprising the hybrid electric drive assembly according to claim 13 or 14.

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