Power transmission system and vehicle with same

Abstract

The invention provides a power transmission system and a vehicle with the same. The powertrain includes: an engine; the output end of the first motor is connected with the output shaft; a second motor; the compound planet gear assembly is connected with the output shaft through the clutch assembly and comprises a planet carrier, a first sun gear, a second sun gear, a gear ring, a short planet gear, a long planet gear and a second planet gear, the output end of the engine is connected with the planet carrier, the second motor is connected with the first sun gear, and the second motor is connected with the second sun gear. The short planetary gear is connected with the planet carrier, the short planetary gear is meshed with part of the long planetary gears, the second planetary gear is connected with the long planetary gears and arranged on the planet carrier, and the long planetary gears and the second planetary gear are coaxially arranged; wherein the clutch assembly is connected with the gear ring, and the gear ring is meshed with the long planetary gear. The problem that a transmission system in the prior art cannot consider performance, cost and occupied space at the same time is solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of power transmission technology, in particular to a power transmission system and a vehicle with the same. BACKGROUND

[0002] At present, people pay more and more attention to the protection of the environment and the efficient use of energy. Therefore, hybrid electric vehicles are becoming the development trend of the automobile industry due to their low emissions and other advantages. In China, research institutions and automobile enterprises attach great importance to the development and research of hybrid electric vehicles. The hybrid power transmission system of the automobile is generally divided into three forms of series, parallel and series-parallel according to the connection mode. The hybrid power mainly makes the engine run in the high efficiency area through the coordinated work of the motor, so as to improve the efficiency of the whole system, and is low in cost, light in weight and compact in structure.

[0003] The existing hybrid power transmission system of the automobile can realize the three modes of series, parallel and series-parallel, but the emphasis of each transmission enterprise is different, and the structural forms also have great differences. The mainstream technical scheme mainly meets the daily needs, and the application range of each transmission mechanism is narrow and cannot take into account the performance, cost and size.

[0004] At present, no effective solution has been proposed for the above technical problems. SUMMARY

[0005] The main purpose of the present application is to provide a power transmission system and a vehicle with the same, so as to solve the problem that the transmission system in the prior art cannot take into account the performance, cost and size of the occupied space.

[0006] In order to achieve the above purpose, according to one aspect of the present application, a power transmission system is provided, comprising: an engine; a first motor, the output end of the first motor being connected with an output shaft; a second motor; a composite planetary gear assembly, the composite planetary gear assembly being connected with the output shaft through a clutch assembly, the composite planetary gear assembly comprising a carrier, a first sun gear, a second sun gear, a ring gear, a short planetary gear, a long planetary gear and a second planetary gear, the output end of the engine being connected with the carrier, the second motor being connected with the first sun gear, the short planetary gear being connected with the carrier, the short planetary gear being engaged with part of the long planetary gear, the second planetary gear being connected with the long planetary gear and being arranged on the carrier, the long planetary gear and the second planetary gear being coaxially arranged; wherein the clutch assembly is connected with the ring gear, the ring gear is engaged with the long planetary gear, one end of the clutch assembly being selectively connected with or disconnected from the output shaft, the other end of the clutch assembly being selectively connected with or disconnected from the carrier.

[0007] Further, the number of teeth of the long planetary gear is not equal to the number of teeth of the second planetary gear.

[0008] Further, the clutch assembly comprises: a first clutch, the first clutch being connected with the ring gear, the first clutch having a first connection state in which the other end of the first clutch is connected with the output shaft, and the first clutch having a first separation state in which the other end of the first clutch is separated from the output shaft; and a second clutch, the second clutch being connected with the ring gear, the second clutch having a second connection state in which the other end of the second clutch is connected with the carrier, and the second clutch having a second separation state in which the other end of the second clutch is separated from the carrier.

[0009] Further, the power transmission system further comprises a brake assembly, the brake assembly comprising: a first brake, one end of the first brake being connected with the first sun gear, the other end of the first brake having a first locking state in which the first brake is connected with the transmission housing, and the other end of the first brake having a first unlocking state in which the first brake is separated from the transmission housing; and a second brake, one end of the second brake being connected with the second sun gear, the other end of the second brake having a second locking state in which the second brake is connected with the transmission housing, and the other end of the second brake having a second unlocking state in which the second brake is separated from the transmission housing.

[0010] Further, the power transmission system further comprises a transmission gear assembly, the transmission gear assembly comprising: a driving gear, the driving gear being connected with the output end of the first motor; a driven gear, the driven gear being connected with the output shaft, one end of the driven gear being engaged with the driving gear, and the other end of the driven gear being selectively connected or disconnected with the first clutch; and an output gear, the output gear being connected with the output shaft, the output gear being engaged with the differential gear of the differential.

[0011] Further, the power transmission system has an electric-only mode, the electric-only mode comprising a first motor first gear mode, a second motor first gear mode, and a second motor second gear mode, wherein, when the power transmission system is in the first motor first gear mode, the first motor is in a working state; when the power transmission system is in the second motor first gear mode, the first clutch is in the first connection state, the second brake is in the second locking state, and the second motor is in the working state; and when the power transmission system is in the second motor second gear mode, the first clutch is in the first connection state, the second clutch is in the second connection state, and the second motor is in the working state.

[0012] Further, the power transmission system has a series working mode, the series working mode comprising a first series working mode and a second series working mode, wherein, when the power transmission system is in the first series working mode, the second clutch is in the second connection state, the second motor is electrically connected with the first motor, the engine is in a working state to drive the second motor to supply power to the first motor, and the first motor is in the working state; and when the power transmission system is in the second series working mode, the second brake is in the second locking state, the second motor is electrically connected with the first motor, the engine is in the working state to drive the second motor to supply power to the first motor, and the first motor is in the working state.

[0013] Further, the power transmission system has a series operation mode, and in the series operation mode, the second motor and the first motor are connected with the battery system, and the battery system is used to supply power to the first motor, or the second motor is used to charge the battery system.

[0014] Further, the power transmission system has a parallel operation mode, and the parallel operation mode includes a first-gear parallel mode, a second-gear parallel mode and a third-gear parallel mode, wherein, in the first-gear parallel mode, the first clutch is in the first connection state, the first brake is in the first locking state, the engine is in the working state, the first motor is connected with the battery system, the first motor has a non-working engine direct driving state, the first motor has a first charging state for charging the battery system, and the first motor has a working state powered by the battery system; in the second-gear parallel mode, the first clutch is in the first connection state, the second clutch is in the second connection state, the engine is in the working state, the first motor and the second motor are connected with the battery system, the first motor has the first charging state for charging the battery system, and the first motor has the working state powered by the battery system, or the second motor has a second charging state for charging the battery system, and the second motor has the working state powered by the battery system; in the third-gear parallel mode, the first clutch is in the first connection state, the second brake is in the second locking state, the engine is in the working state, the first motor and the second motor are connected with the battery system, the first motor has the first charging state for charging the battery system, and the first motor has the working state powered by the battery system, or the second motor has the second charging state for charging the battery system, and the second motor has the working state powered by the battery system.

[0015] Further, the power transmission system has an electronic continuously variable transmission mode, and in the electronic continuously variable transmission mode, the engine is in the working state, the first motor and the second motor are electrically connected, the first motor has a working state for providing power, and the first motor has a first power supply state for supplying power to the second motor, or the second motor has the working state for providing power, and the second motor has a second power supply state for supplying power to the first motor.

[0016] According to another aspect of the present application, a vehicle is provided, and the vehicle has a power transmission system, and the power transmission system is the above-mentioned power transmission system.

[0017] By applying the technical solution of this invention, a composite planetary gear assembly is installed within the transmission. The first and second sun gears of the composite planetary gear assembly share a planet carrier and a ring gear. The engine output is connected to the planet carrier, and the second motor output is connected to the first sun gear. The first sun gear is connected to the ring gear via short and long planetary gears. The composite planetary gear assembly is connected to or disconnected from the output shaft via a clutch assembly, thereby achieving multiple power transmission modes. By using the composite planetary gear assembly, the power transmission system layout is compact, reducing the complexity of the power transmission system, decreasing the size of the transmission, and improving engine operating conditions, effectively reducing fuel consumption. Simultaneously, the dual motors and engine can still achieve multiple operating conditions. Through optimized control strategies, the transmission can switch between different operating modes to meet vehicle driving needs, while ensuring optimal fuel consumption and high-efficiency motor operation. Attached Figure Description

[0018] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0019] Figure 1 A schematic diagram of an embodiment of the power transmission system according to the present invention is shown;

[0020] Figure 2 A schematic diagram of the torque transmission path of a first embodiment of the power transmission system according to the present invention in pure electric mode is shown.

[0021] Figure 3 A schematic diagram of the torque transmission path of a second embodiment of the power transmission system according to the present invention in pure electric mode is shown;

[0022] Figure 4 A schematic diagram of the torque transmission path in a third embodiment of the power transmission system according to the present invention in pure electric mode is shown;

[0023] Figure 5 A schematic diagram of the torque transmission path of a power transmission system according to the present invention in a series operating mode is shown.

[0024] Figure 6 A schematic diagram of the torque transmission path according to a second embodiment of the power transmission system of the present invention in series operation mode is shown;

[0025] Figure 7 A schematic diagram of the torque transmission path of a first embodiment of the power transmission system according to the present invention in parallel operation mode is shown.

[0026] Figure 8Fig. 2 shows a schematic diagram of torque transmission paths of a second embodiment of a power transmission system according to the present application in a parallel operation mode;

[0027] Figure 9 Fig. 3 shows a schematic diagram of torque transmission paths of a third embodiment of a power transmission system according to the present application in a parallel operation mode;

[0028] Figure 10 Fig. 4 shows a schematic diagram of torque transmission paths of a fourth embodiment of a power transmission system according to the present application in a parallel operation mode;

[0029] Figure 11 Fig. 5 shows a schematic diagram of torque transmission paths of a fifth embodiment of a power transmission system according to the present application in a parallel operation mode.

[0030] In the drawings, the following reference numerals are used:

[0031] 1 engine; 2 first electric machine; 3 second electric machine; 4 first clutch; 5 second clutch; 6 first brake; 7 second brake; 8 second sun gear; 9 second planetary gear; 10 first sun gear; 11 short planetary gear; 12 long planetary gear; 13 ring gear; 14 carrier; 15 driven gear; 16 output shaft; 17 differential; 19 driving gear. DETAILED DESCRIPTION

[0032] It should be noted that the embodiments herein and in the dependent claims as well as any features in conjunction therewith can be combined with each other, unless explicitly stated otherwise. Hereinafter, the application will be described in more detail with reference to the enclosed drawings.

[0033] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments consistent with the present application. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and / or "comprising," when used in this specification, specify the presence of stated features, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and / or groups thereof.

[0034] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such terms can be used interchangeably where appropriate so that the embodiments of this application described herein can be implemented, for example, in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0035] Exemplary embodiments according to this application will now be described in more detail with reference to the accompanying drawings. However, these exemplary embodiments may be implemented in many different forms and should not be construed as being limited to the embodiments set forth herein. It should be understood that these embodiments are provided so that the disclosure of this application is thorough and complete, and that the concept of these exemplary embodiments is fully conveyed to those skilled in the art. In the drawings, for clarity, the thickness of layers and regions may be exaggerated, and the same reference numerals are used to denote the same devices, and therefore their description will be omitted.

[0036] Combination Figures 1 to 11 As shown, according to a specific embodiment of this application, a power transmission system is provided.

[0037] Specifically, such as Figure 1 As shown, the power transmission system includes an engine 1, a first motor 2, a second motor 3, and a compound planetary gear assembly. The output end of the first motor 2 is connected to the output shaft 16. The compound planetary gear assembly is connected to the output shaft 16 via a clutch assembly. The compound planetary gear assembly includes a planet carrier 14, a first sun gear 10, a second sun gear 8, a ring gear 13, a short planetary gear 11, a long planetary gear 12, and a second planetary gear 9. The output end of the engine 1 is connected to the planet carrier 14, the second motor 3 is connected to the first sun gear 10, the short planetary gear 11 is connected to the planet carrier 14, the short planetary gear 11 meshes with a portion of the long planetary gear 12, the second planetary gear 9 is connected to the long planetary gear 12 and is mounted on the planet carrier 14, and the long planetary gear 12 and the second planetary gear 9 are coaxially arranged. The clutch assembly is connected to the ring gear 13, the ring gear 13 meshes with the long planetary gear 12, one end of the clutch assembly can be selectively connected to or disconnected from the output shaft 16, and the other end of the clutch assembly can be selectively connected to or disconnected from the planet carrier 14.

[0038] The application discloses a power transmission system of a vehicle, which comprises an engine 1, a first motor 2, a second motor 3, a gearbox and an output shaft 16.

[0039] Specifically, the number of teeth of the long planetary gear 12 is not equal to the number of teeth of the second planetary gear 9. Such a setting can utilize the difference in the number of teeth for speed regulation, so that the power can be optimally distributed in terms of torque and speed during transmission according to actual needs. The unequal number of teeth can enable more accurate and flexible torque and speed adjustment of the system in different working modes, thereby optimizing the performance of the entire drive system. By adjusting the number of teeth, energy loss can be reduced and transmission efficiency can be improved while ensuring power transmission.

[0040] Further, the clutch assembly comprises a first clutch 4 and a second clutch 5. The first clutch 4 is connected with the ring gear 13, and the other end of the first clutch 4 has a first connection state of being connected with the output shaft 16, and the other end of the first clutch 4 has a first separation state of being separated from the output shaft 16. The second clutch 5 is connected with the ring gear 13, and the other end of the second clutch 5 has a second connection state of being connected with the planet carrier 14, and the other end of the second clutch 5 has a second separation state of being separated from the planet carrier 14. The first clutch 4 can be connected or disconnected with the output shaft 16, and the second clutch 5 can be connected or disconnected with the planet carrier 14, so that different working modes can be switched. The system can optimize power distribution by controlling the connection and separation state switching of the first clutch 4 and the second clutch 5 in different working modes, so as to ensure that the engine 1, the first motor 2 and the second motor 3 are all at the optimal working point, thereby improving the overall efficiency and fuel economy of the power transmission system.

[0041] In the embodiment, when the first clutch 4 is in the first connection state, power on the composite planetary gear assembly can be transmitted to the output shaft 16 or the first motor; the second clutch 5 can be switched by being in the second connection state or the second separation state to select direct transmission of power on the planet carrier 14 or power transmission after deceleration through the planetary gear.

[0042] Further, the power transmission system further comprises a brake assembly, the brake assembly comprising a first brake 6 and a second brake 7, one end of the first brake 6 being connected with the first sun gear 10, the other end of the first brake 6 having a first locking state connected with the transmission housing, and the other end of the first brake 6 having a first unlocking state separated from the transmission housing; one end of the second brake 7 being connected with the second sun gear 8, the other end of the second brake 7 having a second locking state connected with the transmission housing, and the other end of the second brake 7 having a second unlocking state separated from the transmission housing. The first brake 6 can connect the first sun gear 10 with the differential housing to realize switching of the first sun gear 10 between the first locking state and the first unlocking state; the second brake 7 can lock and unlock the second sun gear 8. By controlling the locking states of the first sun gear 10 and the second sun gear 8 of the vehicle in different working modes, flexible switching and optimization of the working mode of the power transmission system can be realized.

[0043] It should be noted that the locking states of the brake assembly can prevent unnecessary power flow in specific working conditions of the vehicle, for example, in high-speed driving of the vehicle, the first brake 6 is in the first unlocking state, and the second brake 7 is also in the second unlocking state, which can ensure smoothness of the power transmission system and driving safety.

[0044] Further, as shown in Figure 1 the power transmission system further comprises a transmission gear assembly, the transmission gear assembly comprising a driving gear 19, a driven gear 15 and an output gear, the driving gear 19 being connected with the output end of the first motor 2; the driven gear 15 being connected with the output shaft 16, one end of the driven gear 15 being engaged with the driving gear 19, and the other end of the driven gear 15 being selectively connected or disconnected with the first clutch 4; the output gear being connected with the output shaft 16, and the output gear being engaged with the differential gear of the differential 17. By arranging the transmission gear assembly, the output end of the first motor 2, the output end of the engine 1 and the output end of the second motor 3 can be flexibly arranged in the transmission case, ensuring that power can be accurately and accurately transmitted to the wheels, meeting the driving demand of the vehicle, while realizing higher transmission efficiency, better noise control, more compact space layout and improving the space utilization rate in the transmission case.

[0045] Further, as shown in Figures 2 to 4As shown, the power transmission system has a pure electric mode, the pure electric mode includes a first motor first gear mode, a second motor first gear mode and a second motor second gear mode, wherein, when the power transmission system is in the first motor first gear mode, the first motor 2 is in a working state; when the power transmission system is in the second motor first gear mode, the first clutch 4 is in a first connection state, the second brake 7 is in a second locking state, and the second motor 3 is in a working state; when the power transmission system is in the second motor second gear mode, the first clutch 4 is in the first connection state, the second clutch 5 is in a second connection state, and the second motor 3 is in the working state.

[0046] In the embodiment, as shown in Figure 2 , Figure 2 is a schematic diagram of a torque transmission path when the power transmission system is in the first motor first gear mode, in this mode, the first motor 2 is in a working state, since the output end of the first motor 2 directly passes through the driving gear 19, the driven gear 15, the output gear on the output shaft 16 and the differential gear input to the differential, and the speed of the first motor 2 can be effectively reduced and the transmission of the torque can be provided through the two-stage speed ratio adjustment of the output shaft 16 and the differential 17, which is suitable for pure electric low gear operation of the vehicle. At the same time, in this mode, only the first motor 2 drives, and the first motor 2 can be reversed through the change of the motor control mode, so that the reverse gear function can be realized.

[0047] In the embodiment, as shown in Figure 3 , Figure 3 is a schematic diagram of a torque transmission path when the power transmission system is in the second motor first gear mode, in this mode, the first clutch 4 is in a first connection state, the power on the ring gear 13 can be output through the transmission gear assembly, the second brake 7 is in a second locking state to lock the second sun gear 8, and the second motor 3 is in a working state. The first sun gear 10 to the ring gear 13 is a power transmission relationship of increasing speed and reducing torque, at this time the driving force is provided by the second motor 3, at this time the engine 1 and the first motor 2 are not working, and the power of the second motor 3 is transmitted to the differential 17 through the first clutch 4, the output shaft 16 by the composite planetary gear assembly.

[0048] In the embodiment, as shown in Figure 4 , Figure 4 is a schematic diagram of a torque transmission path when the power transmission system is in the second motor second gear mode, in this mode, the first clutch 4 is in a first connection state, the second clutch 5 is in a second connection state, and the second motor 3 is in a working state. At this time, the first sun gear 10, the planet carrier 14, the ring gear 13 and the second sun gear 8 have the same speed, and the power is transmitted from the second motor 3 to the differential 17 through the second clutch 5, the first clutch 4, the output shaft 16 by the composite planetary gear assembly.

[0049] It should be noted that in the pure electric mode, the second motor 3 has two gears, the first motor 2 has one gear, and the first motor 2 and the second motor 3 work independently, that is, the first motor 2 and the second motor 3 can work at the same time to provide driving force to meet the special working condition of the vehicle in the pure electric mode.

[0050] Further, as shown in Figure 5 , Figure 6 , the power transmission system has a series working mode, and the series working mode includes a first series working mode and a second series working mode. When the power transmission system is in the first series working mode, the second clutch 5 is in the second connection state, the second motor 3 is electrically connected with the first motor 2, the engine 1 is in the working state to drive the second motor 3 to supply power to the first motor 2, and the first motor 2 is in the working state.

[0051] In this embodiment, as shown in Figure 5 , Figure 5 is a schematic diagram of the torque transmission path when the power transmission system is in the first series working mode. In this mode, the second clutch 5 is in the second connection state, the planet carrier 14 is connected with the ring gear 13, the engine 1 is in the working state, the first sun gear 10, the planet carrier 14, the ring gear 13 and the second sun gear 8 have the same speed, and the power is transmitted from the engine 1 to the second motor 3 through the compound planetary gear assembly, that is, the engine 1 drives the second motor 3 to generate electricity, the second motor 3 functions as a generator to provide electric energy for the first motor 2, drives the first motor 2 to rotate, and the first motor 2 transmits power to the output shaft 16 and the differential 17 through the transmission gear assembly.

[0052] In this embodiment, as shown in Figure 6 , Figure 6 is a schematic diagram of the torque transmission path when the power transmission system is in the second series working mode. In this mode, the second brake 7 is in the second locking state to lock the second sun gear 8, the engine 1 is in the working state, the power output by the engine 1 is transmitted to the first sun gear 10 through the planet carrier 14 in the speed-increasing and torque-reducing transmission relationship, the speed is increased and the torque is reduced, the second motor 3 provides electric energy for the first motor 2 to drive the first motor 2 to rotate, and the first motor 2 transmits power to the output shaft 16 and the differential 17 through the transmission gear assembly.

[0053] Specifically, when the power transmission system is in the series working mode, the second motor 3 and the first motor 2 are both connected with the battery system, the battery system is used to supply power to the first motor 2, or the second motor 3 is used to charge the battery system. In this mode, the second motor 3 serves as a generator to provide power for the first motor 2 or charge the battery system, and the first motor 2 serves as a motor to output power, which can be provided by the battery system or the second motor 3.

[0054] It should be noted that when the power generation of the second motor 3 is higher than the demand power of the first motor 2 (i.e. the demand power of the whole vehicle), the excess power is used to charge the battery system; when the power generation of the second motor 3 is lower than the demand power of the first motor 2, the demand power can be supplemented by discharging the battery system, or the working point of the engine 1 is adjusted to increase the power of the engine 1, and then the power generation of the second motor 3 is increased to meet the demand of the first motor 2. The two adjustment methods can be determined according to the working condition of the whole vehicle and the power of the battery system at that time.

[0055] Further, as shown in Figures 7 to 11 , the power transmission system has a parallel working mode, and the parallel working mode includes a first parallel mode, a second parallel mode and a third parallel mode. When the power transmission system is in the first parallel mode, the first clutch 4 is in the first connection state, the first brake 6 is in the first locking state, the engine 1 is in the working state, the first motor 2 is connected with the battery system, the first motor 2 has a non-working engine direct drive state, the first motor 2 has a first charging state for charging the battery system, and the first motor 2 has a working state supplied by the battery system. When the power transmission system is in the second parallel mode, the first clutch 4 is in the first connection state, the second clutch 5 is in the second connection state, the engine 1 is in the working state, the first motor 2 and the second motor 3 are both connected with the battery system, the first motor 2 has the first charging state for charging the battery system, and the first motor 2 has the working state supplied by the battery system, or the second motor 3 has the second charging state for charging the battery system, and the second motor 3 has the working state supplied by the battery system. When the power transmission system is in the third parallel mode, the first clutch 4 is in the first connection state, the second brake 7 is in the second locking state, the engine 1 is in the working state, the first motor 2 and the second motor 3 are both connected with the battery system, the first motor 2 has the first charging state for charging the battery system, and the first motor 2 has the working state supplied by the battery system, or the second motor 3 has the second charging state for charging the battery system, and the second motor 3 has the working state supplied by the battery system.

[0056] In this embodiment, as shown in Figure 7 , Figure 8 , Figure 7 , Figure 8Fig. 2 is a schematic diagram of a torque transmission path when the power transmission system is in a first parallel mode. In this mode, the first clutch 4 is in a first connection state, and the first brake 6 is in a first locking state to lock the output end of the second motor 3 and the first sun gear 10. At this time, the planetary carrier 14 connected to the engine 1 and the ring gear 13 are in a speed reduction and torque increase transmission relationship, and the engine 1 is in a working state. When the first motor 2 is not working, as shown in Fig. 3, the engine 1 directly drives the vehicle, which is the same as the traditional power and is suitable for low-speed working conditions of the vehicle. When the first motor 2 is working, as shown in Fig. 4, the first motor 2 has two working conditions of charging the battery system and supplying power to the battery system from the first motor 2, which can improve the working condition point of the engine 1 or provide power for the vehicle. The working condition of the first motor 2 can be adjusted according to the working condition of the vehicle and the condition of the battery system. Figure 7 Figure 8

[0057] In this embodiment, as shown in Fig. 5, Figure 9 Figure 10 Figure 9 Figure 10 Fig. 6 is a schematic diagram of a torque transmission path when the power transmission system is in a second parallel mode. In this mode, the first clutch 4 is in a first connection state, and the second clutch 5 is in a second connection state. At this time, the first sun gear 10, the planetary carrier 14, the ring gear 13, and the second sun gear 8 have the same speed, and the power is transmitted from the engine 1 to the second motor 3 through the compound planetary gear assembly. At this time, the engine 1 works alone. When the first motor 2 and the second motor 3 are not working, as shown in Fig. 7, the engine 1 directly drives the vehicle, which is the same as the traditional power and is generally suitable for medium-speed working conditions of the vehicle. When the first motor 2 or the second motor 3 is working, the excess power can be charged to the battery system or the battery system can provide power for the working motor of the first motor 2 and the second motor 3. The working condition of the first motor 2 or the second motor 3 is selected according to the working condition of the vehicle, the efficiency condition of the motor, and the condition of the battery system to select a suitable control strategy. Figure 9

[0058] In this embodiment, as shown in Fig. 8, Figure 11 Figure 11 ​​​​​​​Fig. 2 is a schematic diagram of a torque transmission path when the power transmission system is in the third parallel mode, in which the first clutch 4 is in the first connected state, and the second brake 7 is in the second locked state to lock the second sun gear 8. At this time, the planetary carrier 14 to the first sun gear 10 is in a speed-increasing and torque-reducing transmission relationship, and the engine 1 works alone. When the first motor 2 and the second motor 3 do not work, the engine 1 directly drives the vehicle, which is the same as the conventional power. The first motor 2 or the second motor 3 can work to charge the battery system with the excess power, or the battery system can provide power for the working motor.

[0059] Further, the power transmission system has an electronic continuously variable transmission mode. When the power transmission system is in the electronic continuously variable transmission mode, the engine 1 works, the first motor 2 and the second motor 3 are electrically connected, the first motor 2 has a working state of providing power, and the first motor 2 has a first power supply state of supplying power to the second motor 3, or the second motor 3 has a working state of providing power, and the second motor 3 has a second power supply state of supplying power to the first motor 2. In this mode, the first clutch 4 is in the first connected state, and the engine 1, the first motor 2, and the second motor 3 work together to provide the running power and torque of the vehicle through the power split of the complex planetary gear assembly.

[0060] In the embodiment, when the vehicle is in a low-speed working condition, the engine 1 works to provide power, the second motor 3 can generate electricity to provide power to the first motor 2, and the first motor 2 provides power for the system; when the vehicle is in a medium-speed working condition, the engine 1 works to provide power, and the first motor 2 and the second motor 3 select whether to provide power for the system according to the battery system; when the vehicle is in a high-speed working condition, the engine 1 works to provide power, the first motor 2 can generate electricity to provide power to the second motor 3, and the second motor 3 provides power for the system.

[0061] In another embodiment of the present application, the power transmission system also has a parking power generation mode, which can work in series to generate electricity in a parking working condition.

[0062] According to another specific embodiment of the present application, a vehicle is also provided, which has a power transmission system. The power transmission system is the power transmission system in the above-mentioned embodiments. By applying the power transmission system in the above-mentioned embodiments to the vehicle, the vehicle can be flexibly switched between various working modes, and the driving performance and fuel economy of the vehicle are significantly improved.

[0063] The application also provides a preferred embodiment of a power transmission system, which can realize multiple working modes, including pure electric mode, series mode, parallel mode, ECVT mode (Electrical Continuously Variable Transmission), and has the functions of driving power generation, parking power generation, and energy recovery. The pure electric mode meets the working conditions of vehicle starting, low speed, and medium speed; the series mode is more suitable for low speed working conditions of the vehicle; the parallel mode can meet the working conditions of low speed, medium speed, and high speed of the vehicle; and the ECVT meets the working conditions of low speed and medium speed of the vehicle. Through optimization of the control strategy, the transmission is switched between different working modes to meet the vehicle driving requirements, and the fuel consumption rate is in the optimal region and the motor works in the high efficiency region.

[0064] As can be seen from the above description, the power transmission system in the above embodiment has the following beneficial effects: solving the problems of complex power synthesis mechanism, large size, single working mode, low efficiency, or not having pure electric mode of the existing hybrid electric vehicle system, the structure is simple and compact, and the double motor and double planetary gear structure is used to improve the engine working condition, which can effectively reduce fuel consumption. The relative cost of the motor is increased, but the fuel consumption of the vehicle is reduced, the new energy vehicle target is achieved, the energy saving and emission reduction are achieved, and the gradually tightened emission regulations are met. This structure has the advantages of simple and reasonable structure, simple assembly, low cost, good fuel economy, and low emission.

[0065] For ease of description, spatial relative terms such as "above", "upper", "top", "up", and the like can be used herein to describe the spatial relationship between one device or feature and another device or feature as shown in the drawings. It should be understood that the spatial relative terms are intended to include different orientations of the device in use or operation in addition to the orientation of the device described in the drawings. For example, if the device in the drawing is inverted, the device described as "above" or "above" the other device or structure will be positioned "below" or "below" the other device or structure. Thus, the exemplary term "above" can include both "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein are interpreted accordingly.

[0066] It is also important to note that the use of the term "one embodiment", "another embodiment", "an embodiment", etc., does not necessarily refer to the same embodiment. Further, the described features, structures, or characteristics can be combined in any suitable manner in one or more embodiments. It should be noted that, in the description of the embodiments, identical elements have been given the same reference numerals and that, where possible, the same or similar elements are denoted using the same reference numerals in different drawings.

[0067] In the above embodiments, the description of each embodiment focuses on different aspects. The parts not described in detail in a certain embodiment can be referred to the relevant description of other embodiments.

[0068] The above only describes the preferred embodiments of the present application and is not intended to limit the present application. The present application can be variously changed and modified by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A power transmission system, characterized in that, include: Engine (1); The first motor (2) is connected to the output shaft (16) at its output end. Second motor (3); A composite planetary gear assembly is connected to the output shaft (16) via a clutch assembly. The composite planetary gear assembly includes a planet carrier (14), a first sun gear (10), a second sun gear (8), a ring gear (13), a short planetary gear (11), a long planetary gear (12), and a second planetary gear (9). The output end of the engine (1) is connected to the planet carrier (14). The second motor (3) is connected to the first sun gear (10). The short planetary gear (11) is connected to the planet carrier (14). The short planetary gear (11) meshes with a portion of the long planetary gear (12). The second planetary gear (9) is connected to the long planetary gear (12) and is disposed on the planet carrier (14). The long planetary gear (12) and the second planetary gear (9) are coaxially disposed. The clutch assembly is connected to the gear ring (13), the gear ring (13) meshes with the long planetary gear (12), one end of the clutch assembly can be selectively connected to or disconnected from the output shaft (16), and the other end of the clutch assembly can be selectively connected to or disconnected from the planet carrier (14).

2. The power transmission system according to claim 1, characterized in that, The number of teeth of the long planetary gear (12) is not equal to the number of teeth of the second planetary gear (9).

3. The power transmission system according to claim 1 or 2, characterized in that, The clutch assembly includes: A first clutch (4) is connected to the gear ring (13), the other end of the first clutch (4) has a first connected state connected to the output shaft (16), and the other end of the first clutch (4) has a first disengaged state separated from the output shaft (16). The second clutch (5) is connected to the gear ring (13), the other end of the second clutch (5) has a second connected state connected to the planetary carrier (14), and the other end of the second clutch (5) has a second disengaged state separated from the planetary carrier (14).

4. The power transmission system according to claim 3, characterized in that, The power transmission system further includes a braking assembly, which includes: A first brake (6) has one end connected to the first sun gear (10), the other end of the first brake (6) having a first locked state connected to the transmission housing, and the other end of the first brake (6) having a first unlocked state separated from the transmission housing. The second brake (7) has one end connected to the second sun gear (8), the other end of the second brake (7) having a second locked state connected to the transmission housing, and the other end of the second brake (7) having a second unlocked state separated from the transmission housing.

5. The power transmission system according to claim 4, characterized in that, The power transmission system further includes a transmission gear assembly, which includes: A drive gear (19) is connected to the output end of the first motor (2); Driven gear (15), the driven gear (15) is connected to the output shaft (16), one end of the driven gear (15) meshes with the driving gear (19), and the other end of the driven gear (15) can be selectively connected to or disconnected from the first clutch (4); The output gear is connected to the output shaft (16) and meshes with the differential gear of the differential (17).

6. The power transmission system according to claim 4 or 5, characterized in that, The powertrain system has a pure electric mode, which includes a first motor first gear mode, a second motor first gear mode, and a second motor second gear mode. When the power transmission system is in the first motor first gear mode, the first motor (2) is in working state; When the power transmission system is in the first gear mode of the second motor, the first clutch (4) is in the first connected state, the second brake (7) is in the second locked state, and the second motor (3) is in the working state. When the power transmission system is in the second motor second gear mode, the first clutch (4) is in the first connection state, the second clutch (5) is in the second connection state, and the second motor (3) is in the working state.

7. The power transmission system according to claim 4 or 5, characterized in that, The power transmission system has a series operating mode, which includes a first series operating mode and a second series operating mode, wherein... When the power transmission system is in the first series working mode, the second clutch (5) is in the second connection state, the second motor (3) is electrically connected to the first motor (2), the engine (1) is in working state to drive the second motor (3) to supply power to the first motor (2), and the first motor (2) is in working state. When the power transmission system is in the second series working mode, the second brake (7) is in the second locked state, the second motor (3) is electrically connected to the first motor (2), the engine (1) is in working state to drive the second motor (3) to supply power to the first motor (2), and the first motor (2) is in working state.

8. The power transmission system according to claim 7, characterized in that, When the power transmission system is in the series working mode, the second motor (3) and the first motor (2) are both connected to the battery system. The battery system is used to supply power to the first motor (2), or the second motor (3) is used to charge the battery system.

9. The power transmission system according to claim 4 or 5, characterized in that, The powertrain system has parallel operating modes, including first-gear parallel mode, second-gear parallel mode, and third-gear parallel mode. When the power transmission system is in the first gear parallel mode, the first clutch (4) is in the first connected state, the first brake (6) is in the first locked state, the engine (1) is in the working state, the first motor (2) is connected to the battery system, the first motor (2) has a non-working engine direct drive state, and the first motor (2) has a first charging state for charging the battery system, and the first motor (2) has a working state powered by the battery system. When the power transmission system is in the second-gear parallel mode, the first clutch (4) is in the first connection state, the second clutch (5) is in the second connection state, the engine (1) is in the working state, the first motor (2) and the second motor (3) are both connected to the battery system, the first motor (2) has a first charging state for charging the battery system, and the first motor (2) has a working state powered by the battery system, or the second motor (3) has a second charging state for charging the battery system, and the second motor (3) has a working state powered by the battery system; When the power transmission system is in the three-speed parallel mode, the first clutch (4) is in the first connected state, the second brake (7) is in the second locked state, the engine (1) is in the working state, the first motor (2) and the second motor (3) are both connected to the battery system, the first motor (2) has a first charging state for charging the battery system, and the first motor (2) has a working state powered by the battery system, or the second motor (3) has a second charging state for charging the battery system, and the second motor (3) has a working state powered by the battery system.

10. The power transmission system according to claim 4 or 5, characterized in that, The power transmission system has an electronic continuously variable transmission (CVT) mode. When the power transmission system is in the electronic CVT mode, the engine (1) is in a working state, the first motor (2) and the second motor (3) are electrically connected, the first motor (2) has a working state of providing power, and the first motor (2) has a first power supply state of supplying power to the second motor (3), or the second motor (3) has a working state of providing the power, and the second motor (3) has a second power supply state of supplying power to the first motor (2).

11. A vehicle, characterized in that, The vehicle has a power transmission system, which is the power transmission system according to any one of claims 1-10.

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