Dual-motor powertrain capable of split-flow channel cooling and lubrication, and electric vehicle

Abstract

The present application provides a dual-motor powertrain capable of split-flow channel cooling and lubrication, and an electric vehicle. A housing of the dual-motor powertrain comprises two motor accommodating cavities and one reducer accommodating cavity. An oil cooling system of the dual-motor powertrain comprises an oil pump, a heat exchanger, a filter, and a plurality of flow channels. The heat exchanger and the filter are used for splitting oil output by the oil pump. An inlet of the heat exchanger is used for directly receiving the oil output by the oil pump and exchanging heat, and the oil output by the heat exchanger is split by means of at least two flow channels and then cools stators and rotors in the two motor accommodating cavities. An inlet of the filter is used for directly receiving the oil output by the oil pump and filtering same, and the oil output by the filter is split by means of at least two flow channels and then lubricates multiple sets of gears and bearings of two reducers in the reducer accommodating cavity. The heat exchanger and the filter are connected in parallel, and cooling and lubrication oil channels are separated, thereby improving the cooling and lubrication effects of the dual-motor powertrain, reducing the oil resistance of the system, and reducing the power consumption of the oil pump.

Description

Dual-motor powertrain and electric vehicles with split-channel cooling and lubrication

[0001] This application claims priority to Chinese Patent Application No. 202410799083.9, filed on June 19, 2024, entitled "Dual-motor powertrain with split-channel cooling and lubrication and electric vehicle", the entire contents of which are incorporated herein by reference. Technical Field

[0002] This application relates to the field of electric vehicle technology, and in particular to a dual-motor powertrain with split-channel cooling and lubrication and an electric vehicle. Background Technology

[0003] Hybrid electric vehicles (HEVs) are gradually becoming mainstream in the market due to their energy-saving and low-emission features. In the drive system of a HEV, the dual-motor powertrain includes a generator, a drive motor, and a gearbox. Cooling and lubrication of the two motors and the transmission are crucial for ensuring stable operation. Currently, the cooling and lubrication systems of existing new energy electric vehicles are connected in series, forming a series cooling oil circuit to cool and lubricate the various motor components and the gearbox gear shaft system. However, applying this oil-cooling system to the drive system of HEVs results in high oil resistance and low oil pump efficiency. Summary of the Invention

[0004] This application provides a dual-motor powertrain with split-channel cooling and lubrication and an electric vehicle.

[0005] In a first aspect, this application provides a dual-motor powertrain with split-channel cooling and lubrication. The housing of the dual-motor powertrain includes two motor housings and a reducer housing. Each motor housing is used to fix the stator of one motor and house the rotor of one motor. The reducer housing is used to house multiple sets of gear bearings of the two reducers. Each reducer is used to drive one motor in one motor housing. The oil cooling system of the dual-motor powertrain includes an oil pump, a heat exchanger, a filter, and multiple flow channels. The heat exchanger and the filter are used to split the oil output from the oil pump. Specifically, the inlet of the heat exchanger directly receives the oil output from the oil pump and performs heat exchange. The oil output from the heat exchanger is split through at least two flow channels to cool the stator and rotor in the two motor housings. The inlet of the filter directly receives the oil output from the oil pump and performs filtration. The oil output from the filter is split through at least two flow channels to lubricate the multiple sets of gear bearings of the two reducers in one reducer housing.

[0006] In this embodiment, the oil pump provides oil pressure to pump the oil into the heat exchanger and filter. The heat exchanger and filter are used to divert the oil output from the oil pump. By connecting the oil paths of the heat exchanger and filter in parallel, the oil flowing through the heat exchanger does not need to pass through the filter, thereby reducing the flow resistance of the oil transmitted to the stator and rotor of the two motors in the two motor housings. After heat exchange in the heat exchanger, the oil is diverted to the stator and rotor of the two motors in the two motor housings through at least two flow channels to cool the stator and rotor of the two motors, reducing the risk of the two motors overheating and failing to operate normally. Furthermore, the oil flowing through the filter is filtered and impurities removed before flowing directly into the reducer housing to lubricate the multiple sets of gear bearings in the two reducers. This improves the cleanliness of the lubricating oil transmitted to the reducer housing, reduces oil churning losses in the multiple sets of gear bearings in the two reducers, helps reduce system oil resistance, reduces low-pressure power consumption of the oil pump, reduces the cost of the oil pump, and helps achieve maximum cooling efficiency of the dual-motor powertrain.

[0007] In this embodiment, the dual-motor powertrain has two motors and two motor housings. Compared to a single-motor powertrain, the stators and rotors of the two motors in the two motor housings require more cooling oil to cool the motors, which means the oil pump needs more power to drive the oil. The multiple sets of gear bearings in the two reducers have more gear bearings than in a single-motor powertrain, which means the oil quality requirements for lubricating the gear bearings are higher. In this embodiment, the cooling oil path from the oil pump to the stators and rotors of the two motors in the two motor housings is not filtered, so the oil pumped out by the oil pump has low oil resistance while meeting the cooling efficiency of the stators and rotors of the two motors, thereby reducing the power consumption of the oil pump.

[0008] Although the oil has a higher flow resistance after passing through the filter, this oil is used to lubricate multiple sets of gear bearings in the two reducers. The amount of oil used to lubricate multiple sets of gear bearings is relatively less than the flow rate of the oil used to cool the motor. This means that even though the flow resistance of the oil used to lubricate multiple sets of gear bearings is high, it can still meet the needs of lubricating the gear bearings. In addition, the oil after being finely filtered by the filter is of higher quality, with better lubrication effect and lower loss. In addition, during the initial operation of the oil pump, the cleanliness of the oil flowing into the two motor housings to cool the stators and rotors of the two motors is relatively low. As the oil circulates within the two motor housings and the reducer housing, after multiple cycles through the filter, the overall cleanliness of the oil within the dual-motor powertrain housing is improved. This results in the oil pumped out after a period of operation having a higher cleanliness, while maintaining the same power consumption. This higher overall cleanliness allows the stators and rotors of the two motors to be cooled by the high-cleanliness oil, and the multiple sets of gear bearings in the two reducers to be lubricated by the high-cleanliness lubricating oil. This keeps the overall power consumption of the oil pump low and improves the overall lubrication and cooling efficiency of the dual-motor powertrain.

[0009] In one embodiment, the distance between the inlets of an oil pump and a heat exchanger along the oil flow direction is less than the distance between the inlets of an oil pump and a filter.

[0010] In this embodiment, the distance between the inlet of the oil pump and the inlet of the heat exchanger along the oil flow direction is less than the distance between the inlet of the oil pump and the filter. This allows the oil pumped from the oil pump to flow into the heat exchanger first through the inlet, thus facilitating more oil to flow into the inlet of the heat exchanger and then into the stator and rotor in the two motor housings. This allows the stator and rotor of the two motors in the two motor housings to be cooled down more quickly, thereby improving the cooling efficiency of the dual-motor powertrain.

[0011] In this embodiment, the amount of oil flowing through the inlet of the heat exchanger is greater than the amount of oil flowing through the filter. As a result, the amount of cooling oil supplied to the stators and rotors of the two motors in the dual-motor powertrain is greater than the amount of lubricating oil supplied to the multiple sets of gear bearings of the two reducers. This allows the oil pump to meet the cooling requirements of the two motors under high power operation and high heat generation with low power consumption.

[0012] In one embodiment, the distance between the stator and rotor in a heat exchanger and two motor housings along the flow direction of the oil is less than the distance between multiple sets of gear bearings in two reducers in a filter and a reducer housing along the flow direction of the oil.

[0013] In this embodiment, the distance between the stator and rotor in the heat exchanger and the two motor housings along the oil flow direction is less than the distance between the multiple sets of gear bearings in the filter and the reducer housings along the oil flow direction. This allows the oil pumped from the oil pump to flow through the heat exchanger and into the stator and rotor in the two motor housings more quickly via a shorter path, resulting in faster cooling of the stator and rotor of the two motors and improving the cooling efficiency of the dual-motor powertrain. The shorter path between the stator and rotor in the heat exchanger and the two motor housings also reduces the flow resistance of the oil into the stator and rotor in the two motor housings, reducing the low-pressure power consumption of the oil pump. This allows the dual-motor powertrain to maintain good cooling efficiency while keeping the oil pump at a lower power consumption.

[0014] In this embodiment, the path of the oil flowing through the heat exchanger and between the stator and rotor in the two motor housings is relatively short, while the path of the oil flowing through the filter and between the multiple sets of gear bearings in the two reducers is relatively long. This results in a lower flow resistance for the oil flowing through the heat exchanger and between the stator and rotor in the two motor housings, and a higher flow resistance for the oil flowing through the filter and between the multiple sets of gear bearings in the two reducers. Consequently, the amount of cooling oil supplied to the stator and rotor of the two motors in the dual-motor powertrain is greater than the amount of lubricating oil supplied to the multiple sets of gear bearings in the reducer. This allows the oil pump to meet the cooling needs of the two motors operating at high power and generating a large amount of heat while maintaining low power consumption.

[0015] In one embodiment, the inlet diameter of a heat exchanger is larger than the inlet diameter of a filter.

[0016] In this embodiment, the inlet diameter of the heat exchanger is larger than that of the filter inlet. The flow resistance of the oil flowing through the inlet of the heat exchanger is smaller than that flowing through the inlet of the filter. This allows more oil from the oil pump to flow into the heat exchanger from the inlet, where it is cooled and then output to the stator and rotor in the two motor housings. This cooling of the stator and rotor of the two motors improves the cooling efficiency of the dual-motor powertrain, reduces the risk of overheating and failure of the stator and rotor of the two motors, and ensures the normal operation of the dual-motor powertrain.

[0017] In this embodiment, the inlet diameter of the heat exchanger is larger, while the inlet diameter of the filter is smaller. This results in lower flow resistance for the oil entering the heat exchanger and higher flow resistance for the oil entering the filter, making it easier for the oil to flow into the heat exchanger. Consequently, the amount of cooling oil supplied to the stators and rotors of the two motors in the dual-motor powertrain is greater than the amount of lubricating oil supplied to the multiple sets of gear bearings of the two reducers. This allows the oil pump to meet the cooling requirements of the two motors under high-power operation and high heat generation at low power consumption.

[0018] In one embodiment, the housing of the dual-motor powertrain includes an oil pump slot, a filter slot, a heat exchange orifice, and two direct-connection channels. The oil pump slot houses an oil pump, the filter slot houses a filter, the heat exchange orifice connects to the inlet of a heat exchanger, and one direct-connection channel is directly connected to both the oil pump slot and the heat exchange orifice. The orifice diameter of one direct-connection channel is larger than that of the other.

[0019] In this embodiment, a direct-connection channel is directly connected to the oil pump tank and the heat exchange hole. Oil pumped from the oil pump tank flows sequentially through this direct-connection channel and the heat exchange hole into the heat exchanger, where it is cooled and discharged. This cooling oil is then supplied to the stators and rotors of the two motors within their respective housings for cooling. This improves the cooling efficiency of the dual-motor powertrain, reduces the risk of overheating and malfunctions in the two motors, and ensures the normal operation of the dual-motor powertrain. Another direct-connection channel is directly connected between the oil pump tank and the filter tank. Oil pumped from the oil pump tank flows sequentially through this other direct-connection channel and the filter inlet into the filter, where it is filtered. This high-quality lubricating oil is then supplied to the reducer housing, thereby lubricating the multiple sets of gear bearings in the two reducers.

[0020] In this embodiment, the aperture of one direct-connected flow channel is larger than that of the other direct-connected flow channel. The larger aperture reduces the flow resistance of the oil, making the flow resistance of the oil through one direct-connected flow channel less than that through the other. This allows more oil to flow into the heat exchanger through one direct-connected flow channel for cooling, and then into the stators and rotors of the two motors in the two motor housings to cool the stators and rotors of the two motors. This improves the cooling efficiency of the dual-motor powertrain while keeping the oil pump power consumption constant or lower.

[0021] In this embodiment, the housing of the dual-motor powertrain integrates an oil pump slot, a filter slot, a heat exchange hole, and two direct-connection flow channels, which simplifies the oil circuit structure, reduces oil resistance, and reduces oil pump power consumption.

[0022] In one embodiment, the length of one direct-connected channel along the flow direction of the oil is less than the length of the other direct-connected channel.

[0023] In this embodiment, the longer the oil flows through, the greater the overall flow resistance. The length of one direct-connected channel along the oil flow direction is less than the length of the other direct-connected channel. This makes the flow resistance of the oil flowing through one direct-connected channel along the oil flow direction smaller than the flow resistance of the other direct-connected channel. This allows more oil to flow into the heat exchanger through one direct-connected channel for cooling, and then into the stators and rotors of the two motors in the two motor housings to cool the stators and rotors of the two motors, which helps to improve the cooling efficiency of the dual-motor powertrain.

[0024] In this embodiment, one direct-connection channel has a shorter length and the other direct-connection channel has a longer length. This results in lower flow resistance for the oil flowing through one direct-connection channel and higher flow resistance for the oil flowing through the other direct-connection channel. This allows more oil to flow into the heat exchanger through one direct-connection channel, thereby ensuring that the amount of cooling oil supplied to the stators and rotors of the two motors in the dual-motor powertrain is greater than the amount of lubricating oil supplied to the multiple sets of gear bearings of the two reducers. This is beneficial for meeting the cooling requirements of the two motors operating at high power while maintaining or reducing the power consumption of the oil pump.

[0025] In one embodiment, the dual-motor powertrain further includes a valve for adjusting the flow rate of at least one of the oil flowing into a heat exchanger and the oil flowing into a filter.

[0026] In this embodiment, a valve is used to adjust the flow rate of at least one of the oil flowing into the heat exchanger and the oil flowing into the filter. When the operating temperature of the two motors in the two motor housings is high, the valve adjusts the flow rate of the oil flowing into the heat exchanger to be greater than the flow rate of the oil flowing into the filter, thereby allowing more oil to flow into the heat exchanger for heat exchange. The cooling oil is then delivered to the stators and rotors of the two motors in the two motor housings for cooling, which helps ensure the normal operation of the two motors and reduces the risk of overheating. When the operating temperature of the two motors in the two motor housings is low, the valve adjusts the flow rate of the oil flowing into the heat exchanger to be less than the flow rate of the oil flowing into the filter, thereby allowing more oil to flow into the filter for filtration. This improves the quality of the oil in the dual-motor powertrain housing, ensuring that the two motors can be cooled by the high-purity oil when cooling is required, meeting the cooling oil quality requirements of the two motors.

[0027] In this embodiment, by adjusting the flow rate of oil flowing into the heat exchanger and the amount of oil flowing into the filter through valves, the dual-motor powertrain can flexibly distribute the amount of oil according to the ambient temperature or the operating conditions of the electric vehicle. This is beneficial for improving the cooling effect of the dual-motor powertrain and reducing the overall power consumption while keeping the oil pump at a low power consumption.

[0028] In one embodiment, a valve is used to increase the flow rate of oil flowing into a heat exchanger and decrease the flow rate of oil flowing into a filter, while keeping the speed of an oil pump constant.

[0029] In this embodiment, the oil pump speed remains constant, thus keeping the oil pump power consumption constant. Valves are used to increase the flow rate of oil into the heat exchanger and decrease the flow rate of oil into the filter, thereby allowing more oil pumped from the oil pump to flow through the heat exchanger for cooling, and then to be delivered to the stators and rotors of the two motors in the two motor housings for further cooling.

[0030] In this embodiment, the valve reduces the flow rate of oil into the heat exchanger and increases the flow rate of oil into the filter, thereby allowing more oil to flow into the filter for filtration and impurity removal. This improves the quality of the oil within the dual-motor powertrain housing, resulting in high-purity oil. The oil flowing out of the filter further flows into the reducer housing to lubricate the multiple sets of gear bearings in the two reducers, which helps reduce power loss in the dual-motor powertrain and improve its performance.

[0031] In one embodiment, a valve is used when the motors in two motor housings are operating simultaneously to adjust the flow rate of oil flowing into a heat exchanger to a first preset flow rate value and the flow rate of oil flowing into a filter to a second preset flow rate value. When a motor in one of the two motor housings is operating while the other is not, the valve adjusts the flow rate of oil flowing into a heat exchanger to a third preset flow rate value and the flow rate of oil flowing into a filter to a fourth preset flow rate value. The third preset flow rate value is greater than half of the first preset flow rate value, and the fourth preset flow rate value is greater than the second preset flow rate value.

[0032] In this embodiment, the third preset flow rate is greater than half of the first preset flow rate, so that when one motor in the two motor housings is working and the other motor is not working, the working motor can receive a larger amount of cooling oil than the original working motor, which is beneficial to improving the cooling effect of the cooling oil on the working motor and improving the cooling efficiency of the dual-motor powertrain.

[0033] In this embodiment, the fourth preset flow rate value is greater than the second preset flow rate value, so that the oil originally supplied to the stator and rotor of the two motors in the two motor housings for cooling and cooling can be supplied to the stator and rotor of only one motor when only one motor is working. In addition, the increased oil can be distributed to the multiple sets of gear bearings of the two reducers in the reducer housing for lubrication, thereby improving the lubrication effect on the multiple sets of gear bearings of the two reducers.

[0034] In this embodiment, the valve is used to adjust the third preset flow rate value to be greater than half of the first preset flow rate value, and the fourth preset flow rate value to be greater than the second preset flow rate value. This allows the dual-motor powertrain to flexibly adjust the cooling and lubrication of the oil in the dual-motor powertrain when the drive mode changes, so that the dual-motor powertrain can achieve the maximum cooling efficiency and better lubrication effect, optimize the performance of the dual-motor powertrain, and thus optimize the performance of the whole vehicle.

[0035] In one embodiment, one motor housing contains a drive motor, and the other motor housing contains a generator. The housing of the dual-motor powertrain also includes two stator flow channels and two rotor flow channels among multiple flow channels. Oil output from one heat exchanger is delivered to the stator and rotor of the drive motor through one stator flow channel and one rotor flow channel, respectively. Oil output from another heat exchanger is delivered to the stator and rotor of the generator through another stator flow channel and another rotor flow channel, respectively. The sum of the flow rates of the oil delivered through one stator flow channel and one rotor flow channel is greater than the sum of the flow rates of the oil delivered through the other stator flow channel and the other rotor flow channel.

[0036] In this embodiment, the oil flowing from the heat exchanger into one motor housing cavity to cool the stator and rotor of the drive motor and the oil flowing into the other motor housing cavity to cool the stator and rotor of the generator are connected in parallel. This allows the oil cooling out of the heat exchanger to simultaneously cool the stator and rotor of both the drive motor and the generator, which is beneficial for improving the cooling efficiency of the dual-motor powertrain.

[0037] In this embodiment, oil is supplied to the stator and rotor of the drive motor through a stator flow channel and a rotor flow channel, respectively, for cooling the stator and rotor. Oil output from the heat exchanger is supplied to the stator and rotor of the generator through another stator flow channel and another rotor flow channel, respectively, for cooling the stator and rotor.

[0038] In this embodiment, the operating power of the drive motor is greater than that of the generator, and the heat generated by the drive motor is greater than that generated by the generator. The sum of the flow rates of the oil transported by one stator flow channel and one rotor flow channel is greater than the sum of the flow rates of the oil transported by the other stator flow channel and the other rotor flow channel. This results in the amount of oil supplied to the drive motor for cooling being greater than the amount supplied to the generator for cooling. This allows more cooling oil to carry away the heat from the drive motor, which is beneficial for achieving maximum cooling efficiency of the dual-motor powertrain while keeping the oil pump power consumption constant or lower.

[0039] In one embodiment, the housing of the dual-motor powertrain further includes two stator oil outlets. One stator oil outlet penetrates the wall of one motor housing cavity along the radial direction of the dual-motor powertrain, and the other stator oil outlet penetrates the wall of the other motor housing cavity. The diameter of one stator oil outlet is larger than the diameter of the other stator oil outlet.

[0040] In this embodiment, one stator oil outlet penetrates the wall of a motor housing cavity. This stator oil outlet receives oil from a stator flow channel and delivers the oil to the stator of the drive motor for cooling, thereby ensuring the normal operation of the drive motor. The other stator oil outlet penetrates the wall of another motor housing cavity. This other stator oil outlet receives oil from another stator flow channel and delivers the oil to the stator of the generator for cooling, thereby ensuring the normal operation of the generator.

[0041] In this embodiment, the working power of the drive motor is greater than that of the generator, and the heat generated by the drive motor is greater than that generated by the generator. The diameter of one stator oil outlet is larger than that of the other stator oil outlet. The larger diameter results in less flow resistance when the oil flows, which facilitates more oil to flow through one stator oil outlet to the stator of the drive motor in the motor housing cavity, thus cooling the drive motor.

[0042] In one embodiment, the housing of the dual-motor powertrain further includes two rotor oil outlets: one for supplying oil to the rotor of the drive motor, and the other for supplying oil to the rotor of the generator. The diameter of one rotor oil outlet is larger than the diameter of the other rotor oil outlet.

[0043] In this embodiment, one rotor oil outlet is used to deliver oil to the rotor of the drive motor, and another rotor oil outlet is used to receive oil from one rotor flow channel and deliver the oil to the rotor of the drive motor for cooling, thereby ensuring the normal operation of the drive motor. Another rotor oil outlet is used to deliver oil to the rotor of the generator, and yet another rotor oil outlet is used to receive oil from another rotor flow channel and deliver the oil to the rotor of the generator for cooling, thereby ensuring the normal operation of the generator.

[0044] In this embodiment, the working power of the drive motor is greater than that of the generator, and the heat generated by the drive motor is greater than that generated by the generator. The diameter of one rotor oil outlet is larger than that of the other rotor oil outlet. The larger diameter results in less flow resistance when the oil flows, which facilitates more oil to flow through one rotor oil outlet to the rotor of the drive motor in the motor housing cavity, thereby cooling the rotor of the drive motor.

[0045] In one embodiment, the multiple sets of gear bearings of the two reducers include two sets of gear bearings. Gears in one set of gear bearings are used for driving a drive motor housed in one motor housing, and gears in the other set of gear bearings are used for driving a generator housed in another motor housing. The housing of the dual-motor powertrain also includes two lubrication channels among multiple flow channels. Oil output from one filter is delivered to one set of gear bearings through one lubrication channel, and oil output from another filter is delivered to the other set of gear bearings through the other lubrication channel. The flow rate of oil delivered from one lubrication channel to one set of gear bearings is greater than the flow rate of oil delivered from the other lubrication channel to the other set of gear bearings.

[0046] In this embodiment, the oil output from the filter is delivered to a set of gear bearings through a lubrication channel, and the oil output from the filter is delivered to another set of gear bearings through another lubrication channel. This allows the oils that lubricate the first set of gear bearings and the second set of gear bearings to be connected in parallel, so that the oil that has been filtered and purified by the filter can simultaneously lubricate the two sets of gear bearings, which helps to ensure the normal operation of the two sets of gear bearings.

[0047] In this embodiment, because the power of the drive motor is greater than that of the generator, and the drive motor operates for a longer time than the generator operates for a longer time, a larger amount of lubricating oil is required for the set of gear bearings used to drive the drive motor. Furthermore, one set of gear bearings includes three gears, while the other set includes two gear bearings. Therefore, the amount of lubricating oil required for lubricating the gears in the first set is greater than that required for the gears in the second set. The flow rate of lubricating oil delivered to the first set of gear bearings is greater than that delivered to the second set, allowing more lubricating oil to be distributed to the three gears in the first set, which helps ensure adequate lubrication of both sets of gear bearings in the dual-motor powertrain.

[0048] In one embodiment, the housing of the dual-motor powertrain further includes two sets of gear shaft oil outlet holes. Each set of gear shaft oil outlet holes includes multiple gear shaft oil outlet holes. One gear shaft oil outlet hole in one set of gear shaft oil outlet holes is used to deliver oil to one gear or one bearing in a set of gear bearings, and one gear shaft oil outlet hole in the other set of gear shaft oil outlet holes is used to deliver oil to one gear or one bearing in the other set of gear bearings. The diameter of one gear shaft oil outlet hole in one set of gear shaft oil outlet holes is larger than the diameter of one gear shaft oil outlet hole in the other set of gear shaft oil outlet holes.

[0049] In this embodiment, one oil outlet hole of a set of gear shafts delivers oil from the lubrication channel to one gear or bearing in a set of gear bearings for lubrication, thus ensuring the normal operation of the set of gear bearings. Similarly, one oil outlet hole of another set of gear shafts delivers oil from the lubrication channel to one gear or bearing in another set of gear bearings for lubrication, thus ensuring the normal operation of the other set of gear bearings.

[0050] In this embodiment, the number of gears and bearings in one set of gear bearings is greater than that in another set of gear bearings. The amount of oil required to lubricate the gears and bearings in one set of gear bearings is greater than that in the other set. The diameter of one oil outlet hole in one set of gear shafts is larger than that in the other set. The larger diameter results in less flow resistance for the oil, allowing more oil to be delivered from one oil outlet hole in one set of gear shafts to one gear or bearing in the set of gear bearings. This ensures that the set of gear bearings receives more oil for lubrication, which is beneficial for ensuring sufficient lubrication of the two sets of gear bearings in the dual-motor powertrain.

[0051] Secondly, this application provides an electric vehicle, which includes a power battery, a cooling system, and a dual-motor powertrain as described in the first aspect. The power battery is electrically connected to the motor in the dual-motor powertrain, and the cooling system is used to cool the oil in a heat exchanger.

[0052] In the dual-motor powertrain of this application embodiment, by connecting the heat exchanger and filter in parallel, the cooling oil circuit and the lubrication oil circuit are separated. The cooling oil circuit is used to cool the stator and rotor of the two motors, and the lubrication oil circuit is used to lubricate the multiple sets of gear bearings of the two reducers. This can reduce the system oil resistance, reduce the power consumption of the oil pump, thereby reducing the cost of the oil pump, improving the overall cooling efficiency of the dual-motor powertrain and reducing losses. Attached Figure Description

[0053] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the embodiments of this application will be described below.

[0054] Figure 1 is a schematic diagram of the structure of the electric vehicle provided in an embodiment of this application;

[0055] Figure 2 is a schematic diagram of the dual-motor powertrain provided in an embodiment of this application;

[0056] Figure 3 is a schematic diagram of the dual-motor powertrain provided in an embodiment of this application;

[0057] Figure 4 is another structural schematic diagram of the dual-motor powertrain provided in an embodiment of this application;

[0058] Figure 5 is a partial schematic diagram of the dual-motor powertrain shown in Figure 3;

[0059] Figure 6 is another structural schematic diagram of the dual-motor powertrain provided in an embodiment of this application;

[0060] Figure 7 is another structural schematic diagram of the dual-motor powertrain provided in an embodiment of this application;

[0061] Figure 8 is another structural schematic diagram of the dual-motor powertrain provided in an embodiment of this application;

[0062] Figure 9 is another structural schematic diagram of the dual-motor powertrain provided in an embodiment of this application;

[0063] Figure 10 is another structural schematic diagram of the dual-motor powertrain provided in an embodiment of this application. Detailed Implementation

[0064] The technical solutions of the embodiments of this application will be described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments.

[0065] To reduce the system oil resistance of a dual-motor powertrain and lower the low-pressure power consumption of the oil pump, this application provides a dual-motor powertrain with split-flow cooling lubrication. The dual-motor powertrain housing includes two motor housings and one reducer housing. Each motor housing is used to fix the stator of one motor and house the rotor of one motor. The reducer housing houses multiple sets of gear bearings from two reducers. Each reducer is used to drive one motor in one motor housing. The oil cooling system of the dual-motor powertrain includes an oil pump, a heat exchanger, a filter, and multiple flow channels. The heat exchanger and filter are used to split the oil output from the oil pump. The inlet of the heat exchanger directly receives the oil output from the oil pump and performs heat exchange. The oil output from the heat exchanger is split through at least two flow channels to cool the stator and rotor in the two motor housings. The inlet of the filter directly receives the oil output from the oil pump and performs filtration. The oil output from the filter is split through at least two flow channels to lubricate the multiple sets of gear bearings from the two reducers in the reducer housing. This application separates the cooling oil circuit from the lubrication oil circuit by connecting the heat exchanger and filter in parallel. The cooling oil circuit is used to cool the stator and rotor of the motor, while the lubrication oil circuit is used to lubricate multiple sets of gear bearings in the two reducers. This can reduce the system oil resistance, reduce the power consumption of the oil pump, thereby reducing the cost of the oil pump, improving the overall cooling efficiency of the dual-motor powertrain and reducing losses.

[0066] The dual-motor powertrain provided in this application embodiment is applied to electric vehicles to improve the overall performance of electric vehicles.

[0067] Figure 1 is a schematic diagram of the structure of the electric vehicle 1 provided in an embodiment of this application.

[0068] In one embodiment, the electric vehicle 1 includes a dual-motor powertrain 10, a frame 20, a power battery 30, and wheels 40, as shown in Figure 1. The frame 20 is used to fix the dual-motor powertrain 10, the wheels 40, and the power battery 30. The dual-motor powertrain 10 is driveably connected to the wheels 40. The power battery 30 provides electrical energy to the dual-motor powertrain 10, and the dual-motor powertrain 10 can also charge the power battery 30. In one embodiment, the electric vehicle 1 is a car. In one embodiment, the dual-motor powertrain 10 can drive the wheels 40 to rotate, and the electric vehicle 1 is a hybrid electric vehicle.

[0069] Figure 2 is a schematic diagram of the dual-motor powertrain 10 provided in an embodiment of this application.

[0070] In one embodiment, the dual-motor powertrain 10 includes an engine 11, a drive motor 12, a generator 13, a reducer 14, and a power supply device 15. As shown in Figures 1 and 2, the engine 11 is used to output power. For example, the engine 11 can be a combustion engine, including gasoline engines and diesel engines. The generator 13 is driven by the engine 11, and the engine 11 provides power to the generator 13, which converts the kinetic energy output by the engine 11 into electrical energy. The generator 13 is electrically connected to a power battery 30, and the generator 13 can charge the power battery 30 through the power supply device 15. The drive motor 12 is electrically connected to the power battery 30, and the power battery 30 can supply power to the drive motor 12 through the power supply device 15. The drive motor 12 is used to convert the electrical energy output by the power battery 30 into kinetic energy. The drive motor 12, the generator 13, and the drive motor 12 are driven by the wheel 40 through the reducer 14 to provide power to the wheel 40 and drive the wheel 40 to move. In this embodiment, the dual motors in the dual-motor powertrain 10 are the generator 13 and the drive motor 12. In one embodiment, generator 13 can be used as drive motor 12. In one embodiment, the dual motors in dual-motor powertrain 10 can be two drive motors 12.

[0071] Figure 3 is a schematic diagram of the dual-motor powertrain 10 provided in the embodiment of this application. The dashed lines in Figure 3 represent the cooling oil path cooled by the heat exchanger 17. The cooling oil path includes paths L1, L2, L3, and L4. The solid lines represent the lubricating oil path after being filtered and purified by the filter 18. The lubricating oil path includes paths R1, R2, R3, R4, R5, R6, R7, and R8.

[0072] In one embodiment, the dual-motor powertrain 10 further includes an oil pump 16 and a heat exchanger 17, as shown in Figures 2 and 3. The oil pump 16 is used to deliver oil from the oil pan 101 at the bottom of the reducer 14 housing to the reducer housing 300 and the motor housing 200 of the dual-motor powertrain 10 housing for cooling and lubrication of the reducer 14 and motors 12 and 13. The heat exchanger 17 is used to cool the oil flowing through it, thereby allowing the low-temperature oil to cool the drive motor 12 and generator 13. The oil pan 101 refers to the portion at the bottom of the reducer 14 housing used to hold the oil.

[0073] In one embodiment, the electric vehicle 1 further includes a cooling system for cooling the oil in the heat exchanger 17, thereby cooling the oil flowing through the heat exchanger 17.

[0074] In one embodiment, the dual-motor powertrain 10 further includes two filters 18 and 19. Filter 18 is capable of filtering smaller particles than filter 19, as shown in Figure 3. Filter 19 is used to pre-filter impurities in the oil in the oil pan 101, improving the cleanliness of the oil and reducing damage to the oil pump 16 caused by impurities. Filter 18 is used to filter and remove impurities from the oil pumped by the oil pump 16, improving the cleanliness of the oil. In one embodiment, filter 18 is called a fine filter and filter 19 is called a coarse filter.

[0075] The dual-motor powertrain 10 includes a generator 13, a drive motor 12, and a reducer 14. The oil pump 16 needs to supply oil to the generator 13, drive motor 12, and reducer 14 for cooling and lubrication, which results in high oil resistance in the cooling and lubrication oil circuit and high power consumption of the oil pump 16.

[0076] In this embodiment, by connecting the heat exchanger 17 and the filter 18 in parallel, the cooling oil circuit and the lubrication oil circuit are separated, reducing the oil resistance of the oil circuit system, reducing the power consumption of the oil pump 16, and thus reducing the cost of the oil pump 16.

[0077] The following will describe in detail the dual-motor powertrain 10 with split-channel cooling and lubrication provided in the embodiments of this application.

[0078] In one embodiment, the housing of the dual-motor powertrain 10 with split-channel cooling and lubrication includes two motor housings 200 and a reducer housing 300, as shown in Figures 2 and 3. Each motor housing 200 is used to fix the stator of a motor and accommodate the rotor of a motor. The reducer housing 300 is used to accommodate multiple sets of gear bearings 310 of two reducers 14. Each reducer 14 is used to drive a motor in one motor housing 200.

[0079] In one embodiment, the oil cooling system of the dual-motor powertrain 10 includes an oil pump 16, a heat exchanger 17, a filter 18, and multiple flow channels 400, as shown in Figures 2 and 3. The heat exchanger 17 and the filter 18 are used to divert the oil output from the oil pump 16. The inlet 110 of the heat exchanger 17 is used to directly receive the oil output from the oil pump 16 and perform heat exchange. The oil output from the heat exchanger 17 is diverted through at least two flow channels 400 to cool the stator and rotor in the two motor housing cavities 200. The inlet 120 of the filter 18 is used to directly receive the oil output from the oil pump 16 and perform filtration. The oil output from the filter 18 is diverted through at least two flow channels 400 to lubricate multiple sets of gear bearings 310 of the two reducers 14 in the reducer housing 300.

[0080] In this embodiment, oil pump 16 provides oil pressure to pump the oil into heat exchanger 17 and filter 18. Heat exchanger 17 and filter 18 are used to divert the oil output from oil pump 16, connecting the oil paths of heat exchanger 17 and filter 18 in parallel. This eliminates the need for oil flowing through filter 18, thereby reducing the flow resistance of the oil transmitted to the stators and rotors of the two motors 12 and 13 in the two motor housings 200. After heat exchange in heat exchanger 17, the oil is diverted through at least two flow channels 400 to the stators and rotors of the two motors 12 and 13 in the two motor housings 200, cooling the stators and rotors of the two motors 12 and 13 and reducing the risk of overheating and malfunction of the two motors 12 and 13. It also allows the oil flowing through the filter 18 to be filtered and impurities removed before flowing directly into the reducer housing 300 to lubricate the multiple sets of gear bearings 310 of the two reducers 14. This improves the cleanliness of the lubricating oil transmitted to the reducer housing 300, reduces the oil churning loss of the multiple sets of gear bearings 310 of the two reducers 14, helps to reduce system oil resistance, reduce the low-pressure power consumption of the oil pump 16, reduce the cost of the oil pump 16, and helps to achieve the maximum cooling efficiency of the dual-motor powertrain 10.

[0081] In this embodiment, the dual-motor powertrain 10 has two motors 12 and 13 and two motor housings 200. The stators and rotors of the two motors 12 and 13 in the two motor housings 200 require more cooling oil to cool the motors compared to a single-motor powertrain, which means that the oil pump 16 needs more power to drive the oil. The multiple sets of gear bearings 310 of the two reducers 14 have more gear bearings than a single-motor powertrain, which means that the quality requirements of the oil for lubricating the gear bearings are higher. In this embodiment, the cooling oil path from the oil pump 16 to the stators and rotors of the two motors 12 and 13 in the two motor housings 200 is not filtered by the filter 18, so that the oil pumped by the oil pump 16 can meet the cooling efficiency of the stators and rotors of the two motors 12 and 13 while having low oil resistance, thereby reducing the power consumption of the oil pump 16.

[0082] Although the oil resistance is relatively high after passing through filter 18, this oil is used to lubricate the multiple sets of gear bearings 310 of the two reducers 14. The amount of oil used to lubricate the multiple sets of gear bearings 310 is relatively small compared to the flow rate of the oil used to cool the motor. This means that even though the flow resistance of the oil used to lubricate the multiple sets of gear bearings 310 is high, it can still meet the needs of lubricating the gear bearings. Furthermore, the oil after being finely filtered by filter 18 has a higher quality, better lubrication effect, and lower loss. In addition, during the initial working phase of the oil pump 16, the cleanliness of the oil flowing into the two motor housings 200 to cool the stators and rotors of the two motors 12 and 13 is relatively low. Since the oil circulates within the motor housing 200 and the reducer housing 300, after multiple cycles through the filter 18, the overall cleanliness of the oil in the housing of the dual-motor powertrain 10 is improved. This results in the oil pumped by the oil pump 16 having a higher cleanliness after working for a period of time, while maintaining the same power consumption. This allows the stators and rotors of the two motors 12 and 13 to be cooled by the high-cleanliness oil, and the multiple sets of gear bearings 310 of the two reducers 14 to be lubricated by the high-cleanliness lubricating oil. This keeps the overall power consumption of the oil pump 16 low and improves the overall lubrication and cooling efficiency of the dual-motor powertrain 10.

[0083] In one embodiment, one of the two reducers 14 can be used as a speed booster to increase the speed of the kinetic energy from the engine 11 and transmit it to the generator 13 to drive the generator 13 to rotate and generate electricity.

[0084] As shown in Figure 3, in one embodiment, the distance between the oil pump 16 and the inlet 110 of the heat exchanger along the oil flow direction is less than the distance between the oil pump 16 and the inlet 120 of the filter 18.

[0085] In this embodiment of the application, as shown in Figures 2 and 3, the distance between the inlet 110 of the oil pump 16 and the heat exchanger 17 along the oil flow direction is less than the distance between the inlet 120 of the oil pump 16 and the filter 18. This allows the oil pumped from the oil pump 16 to flow into the heat exchanger 17 first through the inlet 110, thereby facilitating more oil to flow into the inlet 110 of the heat exchanger 17. The oil then flows into the stator and rotor of the two motor housings 200, enabling the stator and rotor of the two motors 12 and 13 in the two motor housings 200 to cool down more quickly, thereby improving the cooling efficiency of the dual-motor powertrain 10.

[0086] In this embodiment, a larger amount of oil flows through the inlet 110 of the heat exchanger 17, resulting in a greater amount of oil flowing through the heat exchanger 17 than that flowing through the filter 18. Consequently, the amount of cooling oil supplied to the stators and rotors of the two motors 12 and 13 within the dual-motor powertrain 10 is greater than the amount of lubricating oil supplied to the multiple sets of gear bearings 310 of the two reducers 14. This allows the oil pump 16 to meet the cooling requirements of the high-power operation and large heat generation of the two motors 12 and 13 under low power consumption.

[0087] As shown in Figures 2 and 3, in one embodiment, the distance between the stator and rotor in the heat exchanger 17 and the two motor housings 200 along the oil flow direction is less than the distance between the multiple sets of gear bearings 310 of the two reducers 14 in the filter 18 and the reducer housing 300 along the oil flow direction.

[0088] In this embodiment, the distance between the stator and rotor in the heat exchanger 17 and the two motor housings 200 along the oil flow direction is less than the distance between the multiple sets of gear bearings 310 of the two reducers 14 in the filter 18 and the reducer housing 300 along the oil flow direction. This allows the oil pumped from the oil pump 16 to flow through the heat exchanger 17 and into the stator and rotor in the two motor housings 200 more quickly via a shorter path, resulting in faster cooling of the stator and rotor of the two motors 12 and 13 and improved cooling efficiency of the dual-motor powertrain 10. The shorter path between the stator and rotor in the heat exchanger 17 and the two motor housings 200 also reduces the flow resistance of the oil flowing into the stator and rotor in the two motor housings 200, reducing the low-pressure power consumption of the oil pump 16. This allows the dual-motor powertrain 10 to maintain good cooling efficiency while keeping the oil pump 16 at a lower power consumption.

[0089] In this embodiment, the path of the oil flowing through the heat exchanger 17 and between the stator and rotor in the two motor housings 200 is relatively short, while the path of the oil flowing through the filter 18 and between the multiple sets of gear bearings 310 of the two reducers 14 in the reducer housing 300 is relatively long. This results in a lower flow resistance for the oil flowing through the heat exchanger 17 and between the stator and rotor in the two motor housings 200, and a higher flow resistance for the oil flowing through the filter 18 and between the multiple sets of gear bearings 310 of the two reducers 14 in the reducer housing 300. Consequently, the amount of cooling oil supplied to the stator and rotor of the two motors 12 and 13 in the dual-motor powertrain 10 is greater than the amount of lubricating oil supplied to the multiple sets of gear bearings 310 of the reducer 14. This allows the oil pump 16 to meet the cooling needs of the two motors 12 and 13 when they are operating at high power and generating a large amount of heat, even with low power consumption.

[0090] As shown in Figures 2 and 3, in one embodiment, the flow cross-sectional area of ​​the oil flowing through the heat exchanger 17 is larger than the flow cross-sectional area of ​​the oil flowing through the filter 18.

[0091] In this embodiment, the flow cross-sectional area of ​​the oil flowing through the heat exchanger 17 is larger than that of the oil flowing through the filter 18. This results in a lower flow resistance for the oil flowing through the heat exchanger 17 compared to the filter 18. Consequently, more oil pumped by the oil pump 16 flows into the heat exchanger 17 from the inlet 110, where it is cooled and de-temperatured. This allows more oil to cool the stators and rotors of the two motors 12 and 13 within the two motor housing 200. The larger flow cross-sectional area of ​​the oil flowing through the heat exchanger 17 also reduces the flow resistance, which helps to lower the low-pressure power consumption of the oil pump 16.

[0092] In this embodiment, the heat exchanger 17 has a larger flow cross-sectional area and the filter 18 has a smaller flow cross-sectional area, resulting in lower flow resistance for the oil flowing through the heat exchanger 17 and higher flow resistance for the oil flowing through the filter 18. This makes the amount of cooling oil supplied to the stators and rotors of the two motors 12 and 13 in the dual-motor powertrain 10 greater than the amount of lubricating oil supplied to the multiple sets of gear bearings 310 of the two reducers 14. This allows the oil pump 16 to meet the cooling requirements of the high-power operation and large heat generation of the two motors 12 and 13 under low power consumption.

[0093] In one embodiment, the inlet 110 of the heat exchanger 17 has a larger aperture than the inlet 120 of the filter 18.

[0094] In this embodiment of the application, as shown in Figures 2 and 3, the orifice diameter of the inlet 110 of the heat exchanger 17 is larger than that of the inlet 120 of the filter 18. The flow resistance of the oil flowing through the inlet 110 of the heat exchanger 17 is smaller than that flowing through the inlet 120 of the filter 18. This allows more oil output from the oil pump 16 to flow into the heat exchanger 17 from the inlet 110. After being cooled by the heat exchanger 17, the oil is output to the stator and rotor in the two motor housings 200 for cooling of the stator and rotor of the two motors 12 and 13. This improves the cooling efficiency of the dual-motor powertrain 10, reduces the risk of overheating and failure of the stator and rotor of the two motors 12 and 13, and ensures the normal operation of the dual-motor powertrain 10.

[0095] In this embodiment, the inlet 110 of the heat exchanger 17 has a larger aperture, while the inlet 120 of the filter 18 has a smaller aperture. This results in lower flow resistance for the oil entering the heat exchanger 17 and higher flow resistance for the oil entering the filter 18. Consequently, the amount of cooling oil supplied to the stators and rotors of the two motors 12 and 13 in the dual-motor powertrain 10 is greater than the amount of lubricating oil supplied to the multiple sets of gear bearings 310 of the two reducers 14. This allows the oil pump 16 to meet the cooling requirements of the high-power operation and high heat generation of the two motors 12 and 13 under low power consumption.

[0096] Figure 4 is another structural schematic diagram of the dual-motor powertrain 10 provided in an embodiment of this application.

[0097] In one embodiment, the housing of the dual-motor powertrain 10 includes an oil pump slot 160, a filter slot 180, a heat exchange port 170, and two direct-connection channels 141 and 142, as shown in FIG4. The oil pump slot 160 is used to accommodate an oil pump 16, the filter slot 180 is used to accommodate a filter 18, the heat exchange port 170 is used to connect to the inlet 110 of the heat exchanger 17, one direct-connection channel 141 is directly connected to the oil pump slot 160 and the heat exchange port 170, and the other direct-connection channel 142 is directly connected to the oil pump slot 160 and the filter slot 180. The aperture of the direct-connection channel 141 is larger than the aperture of the direct-connection channel 142.

[0098] In this embodiment of the application, as shown in Figures 2 and 4, the direct connection channel 141 is directly connected to the oil pump tank 160 and the heat exchange hole 170. The oil pumped out from the oil pump tank 160 by the oil pump 16 flows sequentially through the direct connection channel 141 and the heat exchange hole 170 into the heat exchanger 17. The oil is cooled down in the heat exchanger 17, thereby outputting the cooling oil to the stator and rotor of the two motors 12 and 13 in the two motor housing 200 for cooling down. This is beneficial to improving the cooling efficiency of the dual-motor powertrain 10, reducing the risk of overheating and failure of the two motors 12 and 13, and ensuring the normal operation of the dual-motor powertrain 10. The direct flow channel 142 is directly connected between the oil pump tank 160 and the filter tank 180. The oil pumped out from the oil pump tank 160 flows through the direct flow channel 142 and the inlet 120 of the filter 18 in sequence, and then flows into the filter 18. The oil is filtered in the filter 18, thereby outputting high-quality lubricating oil to the reducer housing 300, and then lubricating the multiple sets of gear bearings 310 of the two reducers 14.

[0099] In this embodiment, the aperture of the direct-connection channel 141 is larger than that of the direct-connection channel 142. The larger aperture reduces the flow resistance of the oil, making the flow resistance of the oil through the direct-connection channel 141 less than that through the direct-connection channel 142. This allows more oil to flow into the heat exchanger 17 for cooling, and then into the stators and rotors of the two motors 12 and 13 in the two motor housing 200, further cooling the stators and rotors of the two motors 12 and 13. This improves the cooling efficiency of the dual-motor powertrain 10 while keeping the power consumption of the oil pump 16 constant or lower.

[0100] In this embodiment, the housing of the dual-motor powertrain 10 integrates an oil pump slot 160, a filter slot 180, a heat exchange hole 170, and two direct-connection flow channels 141 and 142, simplifying the oil circuit structure, reducing oil resistance, and decreasing the power consumption of the oil pump 16. In one embodiment, the housing of the dual-motor powertrain 10 is formed by die casting, resulting in a high-strength housing structure and a small size.

[0101] In one embodiment, the length of the direct flow channel 141 along the flow direction of the oil is less than the length of the direct flow channel 142.

[0102] As shown in Figures 2 and 4, in this embodiment, the longer the path through which the oil flows, the greater the overall flow resistance. The length of the direct-connection channel 141 along the oil flow direction is less than the length of the direct-connection channel 142, so that the flow resistance of the oil flowing through the direct-connection channel 141 along the oil flow direction is smaller than that of the direct-connection channel 142 along the oil flow direction. This allows more oil to flow into the heat exchanger 17 for cooling and then into the stators and rotors of the two motors 12 and 13 in the two motor housing 200, cooling and reducing the temperature of the stators and rotors of the two motors 12 and 13, which is beneficial to improving the cooling efficiency of the dual-motor powertrain 10.

[0103] In this embodiment of the application, as shown in FIG4, the length of the direct connection channel 141 is smaller and the length of the direct connection channel 142 is larger. This results in a smaller flow resistance for the oil flowing through the direct connection channel 141 and a larger flow resistance for the oil flowing through the direct connection channel 142. Consequently, the amount of cooling oil supplied to the stators and rotors of the two motors 12 and 13 in the dual-motor powertrain 10 is greater than the amount of lubricating oil supplied to the multiple sets of gear bearings 310 of the two reducers 14. This is beneficial for meeting the cooling requirements of the two motors 12 and 13 at high power operation with the oil pump 16 power consumption remaining unchanged or at a lower power consumption.

[0104] In one embodiment, as shown in FIG4, the two direct-connection channels 141 and 142 each include an inlet and an outlet.

[0105] Figure 5 is a partial schematic diagram of the dual-motor powertrain 10 shown in Figure 3.

[0106] In one embodiment, as shown in FIG5, the two inlets of the two direct-connection channels 141 and 142 converge.

[0107] Figure 6 is another structural schematic diagram of the dual-motor powertrain 10 provided in an embodiment of this application.

[0108] In one embodiment, the dual-motor powertrain 10 further includes a valve 510, as shown in FIG6, for adjusting the flow rate of at least one of the oil flowing into the heat exchanger 17 and the oil flowing into the filter 18.

[0109] In this embodiment, a valve 510 is used to adjust the flow rate of at least one of the oil flowing into the heat exchanger 17 and the oil flowing into the filter 18, as shown in Figures 2 and 6. When the operating temperature of the two motors 12 and 13 in the two motor housing 200 is high, the valve 510 adjusts the flow rate of the oil flowing into the heat exchanger 17 to be greater than the amount of oil flowing into the filter 18, so that more oil can flow into the heat exchanger 17 to exchange heat and deliver the cooling oil to the stator and rotor of the two motors 12 and 13 in the two motor housing 200 for cooling and reducing the temperature of the stator and rotor of the two motors 12 and 13. This helps to ensure the normal operation of the two motors 12 and 13 and reduces the risk of overheating of the two motors 12 and 13.

[0110] When the operating temperature of the two motors 12 and 13 in the two motor housings 200 is low, valve 510 adjusts the flow rate of oil flowing into heat exchanger 17 to be less than the flow rate of oil flowing into filter 18, so that more oil can flow into filter 18 to filter the oil, thereby improving the quality of the oil in the housing of the dual motor power assembly 10. When the two motors 12 and 13 need to be cooled down, they can also be cooled down by high-purity oil, meeting the requirements of the two motors 12 and 13 for the quality of cooling oil.

[0111] In this embodiment, the flow rate of the oil flowing into the heat exchanger 17 and the amount of oil flowing into the filter 18 are adjusted by valve 510, so that the dual-motor powertrain 10 can flexibly distribute the amount of oil according to the ambient temperature or the operating conditions of the electric vehicle 1. This is beneficial for the oil pump 16 to improve the cooling effect of the dual-motor powertrain 10 and reduce the overall power consumption while maintaining low power consumption.

[0112] Figure 7 is another structural schematic diagram of the dual-motor powertrain 10 provided in the embodiment of this application, and Figure 8 is another structural schematic diagram of the dual-motor powertrain 10 provided in the embodiment of this application.

[0113] In one embodiment, valve 510 includes a valve body, as shown in FIG. 6, located at the confluence of the two inlets of two direct-connection channels 141, 142. In one embodiment, the valve body is a solenoid valve. In one embodiment, the valve body is a three-way valve.

[0114] In one embodiment, valve 510 includes a valve body, as shown in FIG7, located in a direct flow channel 141.

[0115] In one embodiment, valve 510 includes a valve body, as shown in FIG8, located in a direct flow channel 142.

[0116] Figure 9 is another structural schematic diagram of the dual-motor powertrain 10 provided in an embodiment of this application.

[0117] In one embodiment, valve 510 includes two valve bodies, as shown in FIG9, the two valve bodies being located at the confluence of the two inlets of the two direct flow channels 141 and 142 and in the direct flow channel 141, respectively.

[0118] In one embodiment, valve 510 includes two valve bodies, as shown in FIG9, the two valve bodies being located at the confluence of the two inlets of the two direct flow channels 141 and 142 and in the direct flow channel 142, respectively.

[0119] In one embodiment, valve 510 includes two valve bodies, as shown in FIG9, the two valve bodies being located in two direct-connection flow channels 141 and 142 respectively.

[0120] As shown in Figure 6, in one embodiment, valve 510 is used to increase the flow rate of oil flowing into heat exchanger 17 and decrease the flow rate of oil flowing into filter 18, while keeping the rotational speed of oil pump 16 constant. Valve 510 is used to decrease the flow rate of oil flowing into heat exchanger and increase the flow rate of oil flowing into filter 18.

[0121] In this embodiment, the rotational speed of the oil pump 16 remains constant, thus keeping the power consumption of the oil pump 16 constant. As shown in Figures 2, 3, and 6, valve 510 is used to increase the flow rate of oil flowing into one heat exchanger 17 and decrease the flow rate of oil flowing into the filter 18, thereby allowing more oil pumped from the oil pump 16 to flow through the heat exchanger 17 for cooling, and then to be delivered to the stators and rotors of the two motors 12 and 13 in the two motor housing cavities 200 for cooling.

[0122] In this embodiment, as shown in Figures 2, 3, and 6, valve 510 is used to reduce the flow rate of oil flowing into heat exchanger 17 and increase the flow rate of oil flowing into filter 18, thereby allowing more oil to flow into filter 18 for filtration and impurity removal. This improves the quality of the oil within the housing of the dual-motor powertrain 10, resulting in high-purity oil. The oil flowing out of filter 18 further flows into reducer housing 300 to lubricate the multiple sets of gear bearings 310 of the two reducers 14, which helps reduce power loss in the dual-motor powertrain 10 and improves its performance.

[0123] As shown in Figures 2, 3, and 6, in one embodiment, valve 510 is used to adjust the flow rate of oil flowing into one heat exchanger 17 to a first preset flow rate value Q1 and the flow rate of oil flowing into the filter 18 to a second preset flow rate value Q2 when the motors in one of the two motor housings 200 are working simultaneously. Valve 510 is also used to adjust the flow rate of oil flowing into the heat exchanger 17 to a third preset flow rate value Q3 and the flow rate of oil flowing into the filter 18 to a fourth preset flow rate value Q4 when the motor in one of the two motor housings 200 is working and the motor in the other is not working. The third preset flow rate value Q3 is greater than half of the first preset flow rate value Q1, and the fourth preset flow rate value Q4 is greater than the second preset flow rate value Q2.

[0124] In this embodiment, the third preset flow rate value Q3 is greater than half of the first preset flow rate value Q1, so that when one motor in the two motor housings 200 is working and the other motor is not working, the working motor can receive a larger amount of cooling oil than the original working motor 12, 13. This is beneficial to improving the cooling effect of the cooling oil on the working motor and improving the cooling efficiency of the dual motor powertrain 10.

[0125] In this embodiment, the fourth preset flow rate value Q4 is greater than the second preset flow rate value Q2. This allows more cooling oil to be supplied to the stator and rotor of the two motors 12 and 13 in the two motor housing 200 when only one motor is working. In addition, the increased oil can be distributed to the multiple gear bearings 310 of the two reducers 14 in the reducer housing 300 for lubrication, thereby improving the lubrication effect on the multiple gear bearings 310 of the two reducers 14.

[0126] In this embodiment, valve 510 is used to adjust the third preset flow rate value Q3 to be greater than half of the first preset flow rate value Q1, and the fourth preset flow rate value Q4 to be greater than the second preset flow rate value Q2. This allows the dual-motor powertrain 10 to flexibly adjust the cooling and lubrication of the oil in the dual-motor powertrain 10 when the drive mode changes, so that the dual-motor powertrain 10 can achieve the maximum cooling efficiency and better lubrication effect, optimize the performance of the dual-motor powertrain 10, and thus optimize the performance of the whole vehicle.

[0127] In one embodiment, the oil flowing out of the heat exchanger 17 is controlled by a valve to ensure that all the oil at a flow rate of a third preset flow rate value Q3 enters the motor housing 200 of a working motor. For example, the oil passage connecting the stator and rotor of a non-working motor can be closed by a valve.

[0128] In one embodiment, one motor housing 200a houses a drive motor 12, and the other motor housing 200b houses a generator 13, as shown in Figures 2 and 3. The housing of the dual-motor powertrain 10 also includes two stator channels 412 and 414 and two rotor channels 411 and 413 among multiple flow channels 400. The oil output from the heat exchanger 17 is transported to the stator and rotor of the drive motor 12 through one stator channel 412 and one rotor channel 411, respectively. The oil output from the heat exchanger 17 is transported to the stator and rotor of the generator 13 through the other stator channel 414 and the other rotor channel 413, respectively. The sum of the flow rates of the oil transported through the stator channel 412 and the rotor channel 411 is greater than the sum of the flow rates of the oil transported through the stator channel 414 and the rotor channel 413.

[0129] In this embodiment, the oil flowing from the heat exchanger 17 into the motor housing 200a to cool the stator and rotor of the drive motor 12 and the oil flowing into the motor housing 200b to cool the stator and rotor of the generator 13 are connected in parallel. This allows the oil cooling out of the heat exchanger 17 to simultaneously cool the stator and rotor of the drive motor 12 and the stator and rotor of the generator 13, which is beneficial to improving the cooling efficiency of the dual-motor powertrain 10.

[0130] In this embodiment, the oil is delivered to the stator and rotor of the drive motor 12 through a stator flow channel 412 and a rotor flow channel 411, respectively, for cooling the stator and rotor of the drive motor 12. The oil output from the heat exchanger 17 is delivered to the stator and rotor of the generator 13 through another stator flow channel 414 and another rotor flow channel 413, respectively, for cooling the stator and rotor of the generator 13.

[0131] In this embodiment, the operating power of the drive motor 12 is greater than that of the generator 13, and the heat generated by the drive motor 12 is greater than that generated by the generator 13. The sum of the flow rates of the oil transported by the stator flow channel 412 and the rotor flow channel 411 is greater than the sum of the flow rates of the oil transported by the stator flow channel 414 and the rotor flow channel 413. This results in the amount of oil supplied to the drive motor 12 for cooling being greater than the amount supplied to the generator 13 for cooling. This allows more cooling oil to carry away the heat from the drive motor 12, which is beneficial for achieving maximum cooling efficiency of the dual-motor powertrain 10 while keeping the power consumption of the oil pump 16 constant or at a lower power consumption.

[0132] In one embodiment, the distance from which the oil delivered by the stator flow channel 412 and the rotor flow channel 411 flows to the stator and rotor of the drive motor 12 is less than the distance from which the oil delivered by the stator flow channel 414 and the rotor flow channel 413 flows to the stator and rotor of the generator 13.

[0133] In this embodiment, the distance from which the oil delivered by the stator flow channel 412 and the rotor flow channel 411 flows to the stator and rotor of the drive motor 12 is less than the distance from which the oil delivered by the stator flow channel 414 and the rotor flow channel 413 flows to the stator and rotor of the generator 13. This results in a shorter flow path for the oil to flow to the stator and rotor of the drive motor 12 compared to the flow path for the oil to flow to the stator and rotor of the generator 13. The shorter path has less flow resistance, allowing more oil to flow through the stator flow channel 412 and the rotor flow channel 411 for cooling the stator and rotor of the drive motor 12. This is beneficial for achieving maximum cooling efficiency of the dual-motor powertrain 10 while keeping the power consumption of the oil pump 16 constant or lower.

[0134] Figure 10 is another structural schematic diagram of the dual-motor powertrain 10 provided in an embodiment of this application. It should be noted that the dashed lines in Figure 10 represent the cooling oil path through the heat exchanger 17, which includes paths L1, L2, L3, and L4. The solid lines represent the lubricating oil path after being filtered and purified by the filter 18, which includes paths R1, R2, R3, R4, R5, R6, R7, and R8.

[0135] In one embodiment, the dual-motor powertrain 10 further includes another valve 520, as shown in Figures 2 and 10. Valve 520 is used to adjust at least one of the flow rates of oil transported through stator channel 412 and rotor channel 411, and the flow rates of oil transported through stator channel 414 and rotor channel 413. Specifically, when the generator 13 and drive motor 12 are operating simultaneously, valve 520 is used to adjust the sum of the flow rates of oil transported through stator channel 412 and rotor channel 411 to be greater than the sum of the flow rates of oil transported through stator channel 414 and rotor channel 413.

[0136] In this embodiment, valve 520 is used to adjust at least one of the flow rates of the oil conveyed through stator flow channel 412 and rotor flow channel 411 and the flow rates of the oil conveyed through stator flow channel 414 and rotor flow channel 413. When the drive motor 12 is working and the generator 13 is not working, valve 520 is used to adjust the sum of the flow rates of the oil conveyed through stator flow channel 412 and rotor flow channel 411 to be greater than the sum of the flow rates of the oil conveyed through stator flow channel 414 and rotor flow channel 413, so that more of the oil cooled by heat exchanger 17 is used to cool the drive motor 12.

[0137] In this embodiment, when the generator 13 and the drive motor 12 are working simultaneously, the working power of the drive motor 12 is greater than that of the generator 13, and the drive motor 12 generates more heat. The valve 520 is used to adjust the sum of the flow rates of the oil transported through the stator flow channel 412 and the rotor flow channel 411 to be greater than the sum of the flow rates of the oil transported through the stator flow channel 414 and the rotor flow channel 413. This allows more cooling oil in the heat exchanger 17 to be transported to the stator and rotor of the drive motor 12 for cooling, which is beneficial to achieving the maximum cooling efficiency of the dual-motor powertrain 10.

[0138] In this embodiment, at least one of the flow rates of the oil delivered through the stator flow channel 412 and the rotor flow channel 411 and the flow rates of the oil delivered through the stator flow channel 414 and the rotor flow channel 413 is adjusted by the valve 520, so that the dual-motor powertrain 10 can flexibly distribute the amount of oil according to the ambient temperature or the operating conditions of the electric vehicle 1. This is beneficial for the oil pump 16 to improve the cooling effect of the dual-motor powertrain 10 and reduce the overall power consumption while maintaining low power consumption.

[0139] As shown in Figure 10, in one embodiment, valve 520 includes a valve body located at the intersection of the inlets of rotor flow channel 411, stator flow channel 412, rotor flow channel 413, and stator flow channel 414. In one embodiment, the valve body is a solenoid valve. In another embodiment, the valve body is a three-way valve.

[0140] In one embodiment, valve 520 includes a valve body located at the junction of the inlets of rotor flow channel 411 and stator flow channel 412, or at the junction of the inlets of rotor flow channel 413 and stator flow channel 414. In one embodiment, the valve body is a two-way valve.

[0141] In one embodiment, valve 520 includes two valve bodies: one valve body is located at the intersection of the inlets of rotor flow channel 411 and stator flow channel 412, and the other valve body is located at the intersection of the inlets of rotor flow channel 413 and stator flow channel 414. In one embodiment, each valve body is a two-way valve.

[0142] In one embodiment, valve 520 is a temperature control valve, as shown in Figures 2 and 10. When the oil is at a low temperature or the ambient temperature is at a low temperature, the temperature sensor transmits a low temperature signal to valve 520. Valve 520 is used to adjust the sum of the flow rates of the oil transported through stator channel 412 and rotor channel 411 to be greater than the sum of the flow rates of the oil transported through stator channel 414 and rotor channel 413.

[0143] In this embodiment, the oil is at a low temperature or the ambient temperature is low, the oil viscosity is high, and the system oil resistance of the dual-motor powertrain 10 is high. It is necessary to quickly raise the oil temperature. Valve 520 is used to adjust the sum of the flow rates of the oil transported through stator channel 412 and rotor channel 411 to be greater than the sum of the flow rates of the oil transported through stator channel 414 and rotor channel 413. This is beneficial for the oil in stator channel 412 and rotor channel 411 with a larger flow rate to absorb more heat generated by the high-power drive motor 12, thereby raising the temperature of the oil in stator channel 412 and rotor channel 411. This allows the stator flow channel 414 and rotor flow channel 413, which have smaller flow rates, to absorb the heat generated by the generator 13. Although the power of the generator 13 is lower than that of the drive motor 12, the smaller flow rates in the stator flow channel 414 and rotor flow channel 413 allow the temperature of the oil in the stator flow channel 414 and rotor flow channel 413 to rise. This, in turn, increases the temperature of the oil in the housing of the dual-motor powertrain 10, thereby reducing the viscosity of the oil, reducing the flow resistance of the oil system, reducing the churning losses of the multiple sets of gear bearings 310 in the two reducers 14, and improving the working efficiency of the oil pump 16.

[0144] In one embodiment, the housing of the dual-motor powertrain 10 further includes two stator oil outlets 103a and 103b, as shown in Figures 2 and 3. One stator oil outlet 103a penetrates the cavity wall of the motor receiving cavity 200a along the radial direction of the dual-motor powertrain 10, and the other stator oil outlet 103b penetrates the cavity wall of the motor receiving cavity 200b. The diameter of the stator oil outlet 103a is larger than the diameter of the stator oil outlet 103b.

[0145] In this embodiment, a stator oil outlet 103a penetrates the wall of the motor receiving cavity 200a. The stator oil outlet 103a receives oil from the stator flow channel 412 and delivers the oil to the stator of the drive motor 12 for cooling, thereby ensuring the normal operation of the drive motor 12. Another stator oil outlet 103b penetrates the wall of the motor receiving cavity 200b. The stator oil outlet 103b receives oil from the stator flow channel 414 and delivers the oil to the stator of the generator 13 for cooling, thereby ensuring the normal operation of the generator 13.

[0146] In this embodiment, the operating power of the drive motor 12 is greater than that of the generator 13, and the heat generated by the drive motor 12 is greater than that generated by the generator 13. The diameter of the stator oil outlet 103a is larger than that of the stator oil outlet 103b. The larger diameter results in less flow resistance when the oil flows, which facilitates more oil to flow through the stator oil outlet 103a to the stator of the drive motor 12 in the motor housing cavity 200a, thus dissipating heat from the drive motor 12.

[0147] In one embodiment, the housing of the dual-motor powertrain 10 further includes two rotor oil outlets 104a and 104b, as shown in Figures 2 and 3. One rotor oil outlet 104a is used to supply oil to the rotor of the drive motor 12, and the other rotor oil outlet 104b is used to supply oil to the rotor of the generator 13. The diameter of the rotor oil outlet 104a is larger than the diameter of the rotor oil outlet 104b.

[0148] In this embodiment, one rotor oil outlet 104a is used to deliver oil to the rotor of the drive motor 12. The rotor oil outlet 104a receives oil from the rotor flow channel 411 and delivers the oil to the rotor of the drive motor 12 for cooling, thereby ensuring the normal operation of the drive motor 12. The other rotor oil outlet 104b is used to deliver oil to the rotor of the generator 13. The rotor oil outlet 104b receives oil from the rotor flow channel 413 and delivers the oil to the rotor of the generator 13 for cooling, thereby ensuring the normal operation of the generator 13.

[0149] In this embodiment, the operating power of the drive motor 12 is greater than that of the generator 13, and the heat generated by the drive motor 12 is greater than that generated by the generator 13. The diameter of the rotor oil outlet 104a is larger than that of the rotor oil outlet 104b. The larger diameter results in less flow resistance when the oil flows, which facilitates more oil to flow through the rotor oil outlet 104a to the rotor of the drive motor 12 in the motor housing cavity 200a, thereby cooling the rotor of the drive motor 12.

[0150] In one embodiment, the two rotor oil outlets 104a and 104b can deliver oil to the rotors of the two motors 12 and 13 through the input shafts 301 and 401 of the two reducers 14 and the motor shafts 201 and 202 of the two motors 12 and 13.

[0151] In one embodiment, the multiple sets of gear bearings 310 of the two reducers 14 include two sets of gear bearings 311 and 312, as shown in Figures 2 and 3. The gears in one set of gear bearings 311 are used to drive the drive motor 12 housed in the motor housing 200a, and the gears in the other set of gear bearings 312 are used to drive the generator 13 housed in the motor housing 200b. The housing of the dual-motor powertrain 10 also includes two lubrication channels 421 and 422 among multiple flow channels 400. The oil output from the filter 18 is delivered to one set of gear bearings 311 through one lubrication channel 421, and the oil output from the filter 18 is delivered to the other set of gear bearings 312 through the other lubrication channel 422. The flow rate of the oil delivered to the one set of gear bearings 311 through the lubrication channel 421 is greater than the flow rate of the oil delivered to the other set of gear bearings 312 through the lubrication channel 422.

[0152] In this embodiment, the oil output from the filter 18 is delivered to a set of gear bearings 311 through a lubrication channel 421, and the oil output from the filter 18 is delivered to another set of gear bearings 312 through another lubrication channel 422. This allows the oils that lubricate the set of gear bearings 311 and the other set of gear bearings 312 to be connected in parallel, so that the oil filtered and purified by the filter 18 can simultaneously lubricate the two sets of gear bearings 311 and 312, which helps to ensure the normal operation of the two sets of gear bearings 311 and 312.

[0153] In this embodiment, since the power of the drive motor 12 is greater than that of the generator 13, the drive motor 12 operates for a longer time than the generator 13 operates for a longer time. Therefore, a larger amount of lubricating oil is required for the set of gear bearings 311 that connect to the drive motor 12. Furthermore, one set of gear bearings 311 includes three gears, while the other set of gear bearings 312 includes two gears. The amount of oil required to lubricate the gears in the set of gear bearings 311 is greater than that required for the other set of gear bearings 312. The flow rate of oil delivered to the set of gear bearings 311 via lubrication channel 421 is greater than the flow rate of oil delivered to the other set of gear bearings 312 via lubrication channel 422. This allows more lubricating oil to be distributed to the three gears in the set of gear bearings 311, which helps ensure adequate lubrication of the two sets of gear bearings 311 and 312 in the dual-motor powertrain 10.

[0154] In one embodiment, the housing of the dual-motor powertrain 10 further includes two sets of gear shaft oil outlet holes 105 and 106, as shown in FIG3. Each set of gear shaft oil outlet holes 105 and 106 includes multiple gear shaft oil outlet holes 105a and 106a. One gear shaft oil outlet hole 105a of one set of gear shaft oil outlet holes 105 is used to deliver oil to one gear or one bearing in a set of gear bearings 311, and one gear shaft oil outlet hole 106a of the other set of gear shaft oil outlet holes 106 is used to deliver oil to one gear or one bearing in another set of gear bearings 312. The diameter of one gear shaft oil outlet hole 105a of one set of gear shaft oil outlet holes 105 is larger than the diameter of one gear shaft oil outlet hole 106a of the other set of gear shaft oil outlet holes 106.

[0155] In this embodiment, one gear shaft oil outlet 105a of a set of gear shaft oil outlets 105 delivers oil from the lubrication channel 421 to one gear or bearing in a set of gear bearings 311 for lubrication, thus ensuring the normal operation of the set of gear bearings 311. Similarly, one gear shaft oil outlet 106a of another set of gear shaft oil outlets 106 delivers oil from the lubrication channel 422 to one gear or bearing in another set of gear bearings 312 for lubrication, thus ensuring the normal operation of the other set of gear bearings 312.

[0156] In this embodiment, the number of gears and bearings in one set of gear bearings 311 is greater than the number of gears and bearings in another set of gear bearings 312. The amount of oil required to lubricate the gears and bearings in one set of gear bearings 311 is greater than the amount required to lubricate the gears and bearings in another set of gear bearings 312. The diameter of one gear shaft oil outlet hole 105a in one set of gear shaft oil outlet holes 105 is larger than the diameter of one gear shaft oil outlet hole 106a in another set of gear shaft oil outlet holes 106. The larger diameter results in less flow resistance for the oil, allowing more oil to be delivered from one gear shaft oil outlet hole 105a in one set of gear shaft oil outlet holes 105 to one gear or one bearing in one set of gear bearings 311. This ensures that one set of gear bearings 311 receives more oil for lubrication, which is beneficial for ensuring sufficient lubrication of the two sets of gear bearings 311 and 312 in the dual-motor powertrain 10.

[0157] In one embodiment, the bearings of each set of gear bearings 311 and 312 are interconnected, and lubricating oil can circulate. The connection between the bearings can be achieved through housing oil passages, shaft oil passages, housing openings, etc.

[0158] As shown in Figure 3, in one embodiment, a set of gear bearings 311 includes an input shaft 301 coaxially fixedly connected to the motor shaft 201 of the drive motor 12, an input wheel 302 fixed to the input shaft 301, an intermediate shaft 303 and an intermediate gear set 304 fixed to the intermediate shaft 303, and an output shaft 305 fixed to the intermediate shaft 303. The output shaft 305 is fixed with an output wheel 306, which transmits power to the differential 102, thereby driving the wheels 40. Bearings are fixed on the motor shaft 201, input shaft 301, intermediate shaft 303 and output shaft 305 for rotatably connecting the motor shaft 201, input shaft 301, intermediate shaft 303 and output shaft 305 to the housing of the dual-motor powertrain 10.

[0159] As shown in Figure 3, in one embodiment, another set of gear bearings 312 includes an output shaft 401 coaxially fixedly connected to the motor shaft 202 of the generator 13, an output wheel 402 fixed on the output shaft 401, and an input shaft 403 drivenly connected to the output shaft 401. An input wheel 404 is fixed to the input shaft 403, which is drivenly connected to the engine 11. The input shaft 403 and the input wheel 404 are used to transmit the kinetic energy of the engine 11 to the output shaft 401 and the output wheel 402, driving the motor shaft 202 of the generator 13 to rotate, generating current to charge the power battery 30. Bearings are fixed on the motor shaft 202, output shaft 401, and input shaft 403 to rotatably connect them to the housing of the dual-motor powertrain 10.

[0160] As shown in Figure 3, in one embodiment, the oil output from the heat exchanger 17 is input to the stator and rotor of the two motors 12 and 13 in the two motor housings 200. It is then transported to the motor shaft 201 of the drive motor 12 via cooling oil path L1 to cool the rotor of the drive motor 12. Cooling oil is also supplied from the housing of the dual-motor powertrain 10 via cooling oil path L2 to the stator of the drive motor 12 for cooling. Cooling oil is supplied to the motor shaft 202 of the generator 13 via cooling oil path L3 to cool the rotor of the generator 13. Finally, cooling oil is supplied from the housing of the dual-motor powertrain 10 to the stator of the generator 13 for cooling.

[0161] As shown in Figure 3, in one embodiment, the oil output from filter 18 is input into the reducer housing 300, and actively lubricates the differential 102 via lubrication path R1. Lubrication path R2 lubricates the intermediate gear set 304 and output wheel 306 on the intermediate shaft 303 of a set of gear bearings 311. Lubrication path R3 actively lubricates the bearings on the intermediate shaft 303 of a set of gear bearings 311. Lubrication path R4 actively lubricates the input wheel 302 and intermediate gear set 304 of a set of gear bearings 311. Lubrication path R6 actively lubricates the bearings on the input shaft 403 of another set of gear bearings 312. Lubrication path R7 actively lubricates the input wheel 404 and output wheel 402 of another set of gear bearings 312.

[0162] As shown in Figure 3, in one embodiment, the oil output by the filter 18 also flows into the two motor housings 200 through the lubricating oil paths R5 and R8, to lubricate the bearings of the motor shafts 201 and 202 of the two motors 12 and 13, which is beneficial to the normal operation of the motor shafts 201 and 202 of the two motors 12 and 13.

[0163] The above provides a detailed description of the dual-motor powertrain and electric vehicle with split-channel cooling and lubrication provided in the embodiments of this application. Specific examples have been used to illustrate the principles and embodiments of this application. The description of the above embodiments is only for the purpose of helping to understand the method and core ideas of this application. At the same time, for those skilled in the art, there will be changes in specific embodiments and application scope based on the ideas of this application. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A dual-motor powertrain with split-channel cooling and lubrication, characterized in that, The housing of the dual-motor powertrain includes two motor housings and one reducer housing. Each motor housing is used to fix the stator of one motor and house the rotor of that motor. The reducer housing houses multiple sets of gear bearings from the two reducers. Each reducer is used to drive one motor in one of the motor housings. The oil cooling system of the dual-motor powertrain includes an oil pump, a heat exchanger, a filter, and multiple flow channels. The heat exchanger and the filter are used to divert the oil output from the oil pump, wherein: The inlet of one heat exchanger is used to directly receive the oil output by one oil pump and perform heat exchange. The oil output by one heat exchanger is diverted through at least two flow channels to cool the stator and rotor in the two motor housing cavities. The inlet of the filter is used to directly receive and filter the oil output by the oil pump. The oil output by the filter is diverted through at least two flow channels to lubricate multiple sets of gear bearings of the two reducers in the reducer housing.

2. The dual-motor powertrain according to claim 1, characterized in that, The distance between the inlet of the oil pump and the inlet of the heat exchanger along the flow direction of the oil is less than the distance between the inlet of the oil pump and the inlet of the filter.

3. The dual-motor powertrain according to claim 1 or 2, characterized in that, The distance between the stator and rotor in the heat exchanger and the two motor housings along the flow direction of the oil is less than the distance between the multiple sets of gear bearings of the two reducers in the filter and the reducer housing along the flow direction of the oil.

4. The dual-motor powertrain according to any one of claims 1-3, characterized in that, The inlet diameter of the heat exchanger is larger than the inlet diameter of the filter.

5. The dual-motor powertrain according to any one of claims 1-4, characterized in that, The housing of the dual-motor powertrain includes an oil pump slot, a filter slot, a heat exchange port, and two direct-connection channels. The oil pump slot houses the oil pump, the filter slot houses the filter, and the heat exchange port connects to the inlet of the heat exchanger. One direct-connection channel is directly connected to the oil pump slot and the heat exchange port, and the other direct-connection channel is directly connected to the oil pump slot and the filter slot. The aperture of one direct-connected flow channel is larger than the aperture of the other direct-connected flow channel.

6. The dual-motor powertrain according to claim 5, characterized in that, The length of one direct-connected flow channel along the flow direction of the oil is less than the length of the other direct-connected flow channel.

7. The dual-motor powertrain according to any one of claims 1-6, characterized in that, The dual-motor powertrain also includes a valve for adjusting the flow rate of at least one of the oil flowing into the heat exchanger and the oil flowing into the filter.

8. The dual-motor powertrain according to claim 7, characterized in that, The valve is used to, while keeping the rotational speed of the oil pump constant, perform the following functions: Increase the flow rate of oil flowing into one of the heat exchangers and decrease the flow rate of oil flowing into one of the filters; Reduce the flow rate of oil flowing into one of the heat exchangers and increase the flow rate of oil flowing into one of the filters.

9. The dual-motor powertrain according to claim 7, characterized in that, The valve is used for: When the motors in the two motor housings are working simultaneously, the flow rate of the oil flowing into one of the heat exchangers is adjusted to a first preset flow rate value, and the flow rate of the oil flowing into one of the filters is adjusted to a second preset flow rate value. When one motor in the two motor housings is working and the other motor is not working, the flow rate of the oil flowing into the heat exchanger is adjusted to a third preset flow rate value, and the flow rate of the oil flowing into the filter is adjusted to a fourth preset flow rate value. The third preset flow rate value is greater than half of the first preset flow rate value, and the fourth preset flow rate value is greater than the second preset flow rate value.

10. The dual-motor powertrain according to any one of claims 1-9, characterized in that, One of the motor housing accommodating cavities houses a drive motor, and the other motor housing accommodating cavities houses a generator. The housing of the dual-motor powertrain also includes two stator flow channels and two rotor flow channels among the plurality of flow channels. The oil output from one heat exchanger is respectively transported to the stator and rotor of the drive motor through one stator flow channel and one rotor flow channel, and the oil output from one heat exchanger is respectively transported to the stator and rotor of the generator through the other stator flow channel and the other rotor flow channel, wherein: The sum of the flow rates of the oil transported by the one stator flow channel and the one rotor flow channel is greater than the sum of the flow rates of the oil transported by the other stator flow channel and the other rotor flow channel.

11. The dual-motor powertrain according to claim 10, characterized in that, The housing of the dual-motor powertrain also includes two stator oil outlets. One stator oil outlet penetrates the wall of one motor housing cavity along the radial direction of the dual-motor powertrain, and the other stator oil outlet penetrates the wall of the other motor housing cavity, wherein: The diameter of one stator oil outlet is larger than the diameter of the other stator oil outlet.

12. The dual-motor powertrain according to claim 10, characterized in that, The housing of the dual-motor powertrain also includes two rotor oil outlets, one for supplying oil to the rotor of the drive motor, and the other for supplying oil to the rotor of the generator, wherein: The diameter of one rotor oil outlet hole is larger than the diameter of the other rotor oil outlet hole.

13. The dual-motor powertrain according to any one of claims 1-12, characterized in that, The multiple sets of gear bearings in the two reducers include two sets of gear bearings. One set of gear bearings is used for transmission connection to a drive motor housed in one of the motor housings, and the other set of gear bearings is used for transmission connection to a generator housed in another motor housing. The housing of the dual-motor powertrain also includes two lubrication channels among the multiple flow channels. Oil output from one filter is delivered to one set of gear bearings through one of the lubrication channels, and oil output from one filter is delivered to the other set of gear bearings through the other lubrication channel, wherein: The flow rate of oil delivered to the set of gear bearings through one lubrication channel is greater than the flow rate of oil delivered to the other set of gear bearings through the other lubrication channel.

14. The dual-motor powertrain according to claim 13, characterized in that, The housing of the dual-motor powertrain also includes two sets of gear shaft oil outlet holes. Each set of gear shaft oil outlet holes includes multiple gear shaft oil outlet holes. One gear shaft oil outlet hole in one set is used to deliver oil to one gear or one bearing in the set of gear bearings, and one gear shaft oil outlet hole in the other set is used to deliver oil to one gear or one bearing in the other set of gear bearings, wherein: The diameter of one of the gear shaft oil outlet holes in the group of gear shaft oil outlet holes is larger than the diameter of one of the gear shaft oil outlet holes in the other group of gear shaft oil outlet holes.

15. An electric vehicle, characterized in that, The electric vehicle includes a power battery, a cooling system, and a dual-motor powertrain as described in any one of claims 1-14, wherein the power battery is electrically connected to a motor in the dual-motor powertrain, and the cooling system is used to cool the oil in one of the heat exchangers.

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