Dual-motor multi-mode power system

Abstract

This invention discloses a dual-motor multi-mode power system, belonging to the technical field of vehicle power systems. It includes a first input shaft and a second input shaft that are rotatably connected, with a main motor and an auxiliary motor respectively connected to the first and second input shafts. A first-gear drive gear is mounted on the first input shaft via a one-way clutch, and a second-gear drive gear is loosely fitted on the first input shaft. The system includes a first clutch for controlling the engagement and disengagement of the second-gear drive gear with the first input shaft, and a second clutch for controlling the engagement and disengagement of the first-gear drive gear with the second input shaft. It also includes a control system that controls the power system to drive the vehicle in one of six operating modes: main motor first-gear drive mode, auxiliary motor first-gear drive mode, dual-motor first-gear drive mode, main motor second-gear drive mode, dual-motor second-gear drive mode, and dual-motor reverse drive mode. This invention enables multi-mode drive and multi-gear output, adapting to various complex working conditions, and boasts high efficiency, balancing power and economy.

Description

Technical Field

[0001] This invention relates to a dual-motor multi-mode power system, and more particularly to a dual-motor multi-mode power system for pure electric vehicles, belonging to the field of vehicle power system technology. Background Technology

[0002] Currently, most pure electric vehicles (EVs) use a single motor paired with a single-stage reducer in their powertrain systems. However, EVs need to meet the demands of low-speed, high-torque operation during start-up and hill climbing, and high-speed, low-torque operation on flat roads. This results in motors with very high rated power, leading to low motor load rates in most operating conditions. Furthermore, the wide operating range means the motor cannot consistently operate at its highest efficiency, wasting battery energy and reducing driving range. This results in poor start-up and hill-climbing capabilities, as well as poor high-speed performance. Additionally, a single high-power motor is bulky and expensive. Therefore, a dual-motor powertrain system is a good solution to improve the power and economy of pure electric vehicles.

[0003] Chinese patent number 201510704991.6 discloses a dual-motor power drive assembly. The main motor is connected to the center position of an electromagnetic commutator, while the auxiliary motor is directly connected to the ring gear of a planetary mechanism and simultaneously connected to the left working position of the electromagnetic commutator. The right working position of the electromagnetic commutator is directly connected to the sun gear of the planetary mechanism. The ring gear of the planetary mechanism is connected to the gearbox via a first one-way bearing, and the sun gear is connected to the gearbox via a second one-way bearing. The planetary carrier, as the output, is connected to the second-stage double gear, which in turn connects to the differential input gear to output power. For low-to-medium speed, low torque, a single motor drive is used to increase the motor load rate; for medium-to-high torque, dual-motor torque coupling drive is used; and for high-to-high torque, dual-motor speed coupling drive is used, ensuring both power and economy during electric vehicle operation. This dual-motor power drive assembly overcomes the problems of high motor power, low efficiency, poor power performance, and high cost inherent in single-motor power systems. However, it still suffers from drawbacks such as limited drive modes and the inability to achieve multi-gear output. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to overcome the above-mentioned problems and provide a dual-motor multi-mode power system with multiple drive modes, multiple output levels, high working efficiency and low energy loss.

[0005] The technical solution of this invention is:

[0006] A dual-motor multi-mode power system includes a drive motor, an input shaft assembly, an intermediate shaft assembly, a first clutch, and a second clutch. The input shaft assembly includes an input shaft and a first-speed drive gear and a second-speed drive gear mounted on the input shaft. The intermediate shaft assembly includes an intermediate shaft parallel to the input shaft and a first-speed driven gear and a second-speed driven gear fixedly connected to the intermediate shaft. The first-speed driven gear meshes with the first-speed drive gear, and the second-speed driven gear meshes with the second-speed drive gear. The intermediate shaft assembly drives the wheels of an electric vehicle via a differential. The system is characterized by:

[0007] The drive motor includes a main motor and an auxiliary motor symmetrically arranged at both ends of the input shaft. The input shaft includes a first input shaft and a second input shaft rotatably connected by bearings. The other end of the first input shaft is connected to the main motor, and the other end of the second input shaft is connected to the auxiliary motor. The first gear drive gear is mounted on the first input shaft via a one-way clutch. The one-way clutch is configured to allow the first gear drive gear to rotate in the forward direction relative to the first input shaft, and to lock it in the reverse direction. The second gear drive gear is loosely fitted on the first input shaft. Engaging or disengaging the first clutch causes the second gear drive gear to engage or disengage from the first input shaft, and engaging or disengaging the second clutch causes the first gear drive gear to engage or disengage from the second input shaft.

[0008] The dual-motor multi-mode power system has six operating modes, including:

[0009] In the first gear drive mode of the main motor, the main motor starts and rotates forward, the auxiliary motor stops, the first clutch and the second clutch are both disengaged, and the power of the main motor is transmitted to the first gear drive gear through the first input shaft and the one-way clutch. The first gear drive gear drives the wheels forward at low speed through the intermediate shaft assembly and the differential.

[0010] In the first gear drive mode of the auxiliary motor, the main motor stops and the auxiliary motor starts to rotate forward. The first clutch disengages and the second clutch engages. The power of the auxiliary motor is transmitted to the first gear drive gear through the second input shaft and the second clutch. The one-way clutch overruns and unlocks, and the first input shaft slips with the first gear drive gear. The first gear drive gear drives the wheels forward at low speed through the intermediate shaft assembly and the differential.

[0011] In the dual-motor first-gear drive mode, both the main motor and the auxiliary motor start rotating forward. The first clutch disengages and the second clutch engages. The power of the main motor is transmitted to the first-gear drive gear via the first input shaft and the one-way clutch. The power of the auxiliary motor is transmitted to the first-gear drive gear via the second input shaft and the second clutch. The power of the main and auxiliary motors is superimposed to form the first combined power. The first combined power drives the wheels forward at low speed via the intermediate shaft assembly and the differential.

[0012] In the second-speed drive mode of the main motor, the main motor starts and rotates forward, the auxiliary motor stops, the first clutch engages, the second clutch disengages, the power of the main motor is transmitted to the second-speed drive gear through the first input shaft and the first clutch, the one-way clutch overruns and unlocks, the first-speed drive gear spins freely on the first input shaft, and the second-speed drive gear drives the wheels forward at high speed through the intermediate shaft assembly and differential.

[0013] In the dual-motor two-speed drive mode, the main motor starts rotating forward, and the auxiliary motor starts rotating at high speed. Both the first and second clutches are engaged. The power of the main motor is transmitted to the second-speed drive gear through the first input shaft and the first clutch, and the power of the auxiliary motor is transmitted to the first-speed drive gear through the second input shaft and the second clutch, driving the first-speed drive gear to rotate at high speed. The one-way clutch is overrun and unlocked, and the first-speed drive gear slips off the first input shaft. The power of the main and auxiliary motors is superimposed into a second combined power through the transmission coupling of the first-speed drive gear, the intermediate shaft assembly, and the second-speed drive gear. The second combined power drives the wheels forward at high speed through the intermediate shaft assembly and the differential.

[0014] In the dual-motor reverse drive mode, both the main motor and the auxiliary motor start and reverse. The first clutch disengages and the second clutch engages. The power of the auxiliary motor is transmitted to the first gear drive gear through the second input shaft and the second clutch, causing the first gear drive gear to reverse. The main motor drives the first input shaft to rotate in the opposite direction, preventing the auxiliary motor from driving the main motor to rotate through the first gear drive gear and the one-way clutch. The first gear drive gear drives the wheels to reverse at low speed through the intermediate shaft assembly and the differential.

[0015] It also includes a control system for responding to a request from the vehicle controller to control the dual-motor multi-mode powertrain to drive the vehicle in one of the six operating modes described above.

[0016] Furthermore, in the aforementioned dual-motor multi-mode power system, the first clutch includes a housing disposed between the second-gear drive gear and the main motor, and within the housing sequentially arranged a first friction pair, a relative rotation actuator, a second friction pair, and a first electromagnet. The housing is connected to the second-gear drive gear. The driving friction plate of the first friction pair is connected to the first input shaft, and the driven friction plate is connected to the housing. The driving friction plate of the second friction pair is connected to the housing, and the driven friction pair is connected to the relative rotation actuator. When the first electromagnet is energized, the driving and driven friction plates of the second friction pair press against each other, thereby causing the relative rotation actuator to rotate relative to each other and generate axial movement to press against the driving and driven friction plates of the first friction pair, thus engaging the second-gear drive gear with the first input shaft. When the first electromagnet is de-energized, the second-gear drive gear disengages from the first input shaft. Using a wet friction plate clutch not only results in less impact and no jerking, but also less wear, lower temperature rise, longer service life, and the ability to transmit larger torques.

[0017] Furthermore, in the aforementioned dual-motor multi-mode power system, the second clutch includes an electromagnetic thruster, a clutch disc, and a return spring sequentially disposed between the auxiliary motor and the first-gear drive gear. The clutch disc is circumferentially fixed to the second input shaft and rotates synchronously with the second input shaft. A toothed locking connection structure is provided between the clutch disc and the first-gear drive gear. The on / off state of the electromagnetic thruster can cause the clutch disc to move axially along the second input shaft and lock or disengage from the first-gear drive gear, thereby causing the first-gear drive gear to engage or disengage from the second input shaft. The return spring applies a force to the clutch disc, causing it to tend to move away from the first-gear drive gear.

[0018] The beneficial effects of this invention are:

[0019] 1. The dual-motor layout can improve the power performance of electric vehicles. By driving the two motors separately or in combination, the load rate of the motors can be increased. By adjusting the working state of the two motors, the motors can always work in their high-efficiency range, which can improve energy utilization and increase the driving range of electric vehicles. At the same time, it avoids the problem of high cost of high-power and high-torque motors, and balances power and economy.

[0020] 2. By controlling the different working states of the two motors, multiple driving modes can be realized to meet the needs of electric vehicles in various working conditions such as low speed and low torque, medium-low speed and medium torque, low speed and high torque, high speed and low torque, and reversing, thereby improving the adaptability of pure electric vehicles to complex driving conditions.

[0021] 3. The two-speed reducer provides two reduction ratios, enabling multi-speed output, further expanding the high-efficiency range of the motor, balancing the power and economy of the electric vehicle, reducing motor energy consumption, extending service life, and reducing noise, vibration and component wear during high-speed driving; and the one-way clutch enables overtaking shifting, with no power interruption during shifting, and the shifting process is smooth and shock-free. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the structure of an embodiment of the present invention.

[0023] Figure 2 A schematic diagram of power transmission in the first gear drive mode of the main motor.

[0024] Figure 3 This is a schematic diagram of power transmission in the first-gear drive mode of the auxiliary motor.

[0025] Figure 4 This is a schematic diagram of power transmission in a dual-motor, single-speed drive mode.

[0026] Figure 5 This is a schematic diagram of power transmission in the second-speed drive mode of the main motor.

[0027] Figure 6 This is a schematic diagram of power transmission in a dual-motor, two-speed drive mode.

[0028] Figure 7 This is a schematic diagram of power transmission in a dual-motor reverse drive mode.

[0029] Figure 8 for Figure 1 Enlarged structural diagram of the first clutch.

[0030] Figure 9 for Figure 1 Enlarged structural diagram of the second clutch.

[0031] In the diagram: M1, main motor; M2, auxiliary motor; 1, input shaft; 1a, first input shaft; 1b, second input shaft; 11, first gear drive gear; 12, second gear drive gear; 21, first gear driven gear; 22, second gear driven gear; 3, one-way clutch; 4, first clutch; 41, housing; 42, first friction pair; 43, second friction pair; 44, first electromagnet; 45, first cam plate; 46, second cam plate; 47, ball bearing; 5, second clutch; 51, clutch disc; 52, return spring; 53, annular housing; 54, second electromagnet; 55, annular support sleeve; 56, sliding sleeve; 6, differential. Detailed Implementation

[0032] The present invention will now be further described in conjunction with the accompanying drawings and embodiments:

[0033] In the description of this invention, it should be understood that the orientation or positional relationship indicated by terms such as "inner", "outer", "forward", and "reverse" is based on the orientation or positional relationship shown in the accompanying drawings and is only for the convenience of describing this invention, and is not intended to indicate or imply that the device or component referred to must have a specific orientation, and therefore should not be construed as a limitation of this invention.

[0034] like Figure 1 As shown, this embodiment provides a dual-motor multi-mode power system, including a drive motor, an input shaft assembly, an intermediate shaft assembly, a first clutch 4, and a second clutch 5.

[0035] The input shaft assembly includes an input shaft 1 and a first-speed drive gear 11 and a second-speed drive gear 12 mounted on the input shaft 1. The intermediate shaft assembly includes an intermediate shaft 2 parallel to the input shaft 1 and a first-speed driven gear 21 and a second-speed driven gear 22 fixedly connected to the intermediate shaft 2. The first-speed driven gear 21 meshes with the first-speed drive gear 11 for transmission, and the second-speed driven gear 22 meshes with the second-speed drive gear 12 for transmission. The intermediate shaft assembly drives the wheels of the electric vehicle via a differential 6.

[0036] The drive motor includes a main motor M1 and an auxiliary motor M2 symmetrically arranged at both ends of the input shaft 1. The input shaft 1 includes a first input shaft 1a and a second input shaft 1b rotatably connected. The other end of the first input shaft 1a is connected to the main motor M1, and the other end of the second input shaft 1b is connected to the auxiliary motor M2. A first-gear drive gear 11 is mounted on the first input shaft 1a via a one-way clutch 3. The one-way clutch 3 is configured to allow the first-gear drive gear 11 to rotate in the forward direction relative to the first input shaft 1a, and to lock it in the reverse direction. When locked, the first-gear drive gear 11 rotates synchronously with the first input shaft 1a, and the second-gear drive gear 12 is loosely fitted on the first input shaft 1a. A first clutch 4 is located on the first input shaft 1a, between the second-gear drive gear 12 and the main motor M1. When the first clutch 4 is engaged, the second-gear drive gear 12 is engaged with the first input shaft 1a and rotates synchronously. When the first clutch 4 is disengaged, the second-gear drive gear 12 is disengaged from the first input shaft 1a. The second clutch 5 is mounted on the second input shaft 1b and is located between the first gear drive gear 11 and the auxiliary motor M2. When the second clutch 5 is engaged, the first gear drive gear 11 and the second input shaft 1b are engaged and rotate synchronously. When the second clutch 5 is disengaged, the first gear drive gear 11 is disengaged from the second input shaft 1b.

[0037] The dual-motor multi-mode power system has six operating modes, including: main motor first gear drive mode, main motor first gear drive mode, dual motor first gear drive mode, main motor second gear drive mode, dual motor second gear drive mode, and dual motor reverse gear drive mode. A detailed analysis of each operating mode is provided below:

[0038] Main motor first-speed drive mode: such as Figure 2 As shown, the main motor M1 starts rotating forward, the auxiliary motor M2 stops, and both the first clutch 4 and the second clutch 5 disengage. At this time, the one-way clutch 3 locks. The power of the main motor M1 is transmitted to the first gear drive gear 11 through the first input shaft 1a and the one-way clutch 3. The first gear drive gear 11 drives the wheels forward at low speed through the intermediate shaft assembly and the differential 6. In this mode, the main motor M1 works alone, driven in first gear. The main motor M1 has relatively large power and torque, as well as relatively large rated speed and rated torque. Therefore, this mode is suitable for medium-low speed and medium torque conditions, allowing the main motor M1 to operate in its high-efficiency range as much as possible.

[0039] Main motor first-speed drive mode: such as Figure 3As shown, the main motor M1 stops, and the auxiliary motor M2 starts rotating forward. The first clutch 4 disengages, and the second clutch 5 engages. The power of the auxiliary motor M2 is transmitted to the first gear drive gear 11 via the second input shaft 1b and the second clutch 5. At this time, the one-way clutch 3 is overrun and unlocked, and the first input shaft 1a slips with the first gear drive gear 11. The first gear drive gear 11 drives the wheels forward at low speed via the intermediate shaft assembly and the differential 6. In this mode, the auxiliary motor M2 works alone, driving in first gear. The auxiliary motor M2 has relatively low power and torque, as well as relatively low rated speed and rated torque. Therefore, this mode is suitable for low-speed, low-torque conditions, avoiding the economic disadvantage of traditional electric vehicles where a single motor drive is too powerful for the vehicle's needs. It allows the auxiliary motor M2 to operate within its high-efficiency range as much as possible.

[0040] Dual-motor single-speed drive mode: such as Figure 4 As shown, both the main motor M1 and the auxiliary motor M2 start rotating forward. The first clutch 4 disengages, and the second clutch 5 engages. At this time, the one-way clutch 3 is locked. The power of the main motor M1 is transmitted to the first gear drive gear 11 via the first input shaft 1a and the one-way clutch 3. The power of the auxiliary motor M2 is transmitted to the first gear drive gear 11 via the second input shaft 1b and the second clutch 5. The power of the main and auxiliary motors M2 is superimposed to form the first combined power. The first combined power drives the wheels forward at low speed through the intermediate shaft assembly and the differential 6. In this mode, the two motors work together in first gear, which is suitable for low-speed, high-torque conditions such as starting, low-speed climbing, or low-speed rapid acceleration. By superimposing the power of the two motors, the torque capacity of each individual motor can be greatly reduced. Moreover, through reasonable torque distribution between the two motors, the high efficiency of each motor can be fully utilized.

[0041] Main motor two-speed drive mode: such as Figure 5 As shown, the main motor M1 starts and rotates forward, while the auxiliary motor M2 stops. The first clutch 4 engages, and the second clutch 5 disengages. The power from the main motor M1 is transmitted to the second-gear drive gear 12 via the first input shaft 1a and the first clutch 4. The second-gear drive gear 12 drives the first-gear drive gear 11 to rotate forward through the second-gear driven gear 22, the intermediate shaft, and the first-gear driven gear 21. After two-stage acceleration, the speed of the first-gear drive gear 11 is much higher than that of the first input shaft 1a. The one-way clutch 3 is overrun and unlocked, and the first-gear drive gear 11 spins freely on the first input shaft 1a. The second-gear drive gear 12 drives the wheels forward at high speed via the intermediate shaft assembly and the differential 6. In this mode, the main motor M1 works independently, driven in second gear, which is suitable for high-speed, low-torque conditions. By shifting gears to reduce the speed of the main motor M1 at high speeds, the working efficiency of the main motor M1 is improved, the energy consumption of the motor is reduced, and noise, vibration, and component wear are also reduced at high speeds.

[0042] Dual-motor two-speed drive mode: such as Figure 5As shown, the main motor M1 starts rotating forward, and the auxiliary motor M2 starts rotating at high speed. Both the first clutch 4 and the second clutch 5 are engaged. The power from the main motor M1 is transmitted to the second-gear drive gear 12 via the first input shaft 1a and the first clutch 4. The power from the auxiliary motor M2 is transmitted to the first-gear drive gear 11 via the second input shaft 1b and the second clutch 5, causing the first-gear drive gear 11 to rotate at high speed. At this time, the one-way clutch 3 is overrun and unlocked, and the first-gear drive gear 11 slips off the first input shaft 1a. The power from the main and auxiliary motors M2, after being coupled through the first-gear drive gear 11, the intermediate shaft assembly, and the second-gear drive gear 12, drives the wheels forward at high speed via the intermediate shaft assembly and the differential 6. In this mode, the two motors work together in second gear, providing short-term high power under high-speed conditions.

[0043] Dual-motor reverse drive mode: such as Figure 7 As shown, both the main motor M1 and the auxiliary motor M2 start and reverse. The first clutch 4 disengages, and the second clutch 5 engages. The power of the auxiliary motor M2 is transmitted to the first gear drive gear 11 via the second input shaft 1b and the second clutch 5, causing the first gear drive gear 11 to reverse. The main motor M1 drives the first input shaft 1a to rotate in the opposite direction, preventing the auxiliary motor M2 from driving the main motor M1 to rotate via the first gear drive gear 11 and the one-way clutch 3. The first gear drive gear 11 drives the wheels to reverse at low speed via the intermediate shaft assembly and the differential 6. In this mode, the two motors work in reverse, with first gear drive, which is suitable for low-speed, high-torque reversing conditions.

[0044] The dual-motor multi-mode powertrain also includes a control system (not shown in the figure) for responding to a request from the vehicle controller to control the powertrain to drive the vehicle in one of the six operating modes mentioned above.

[0045] In this embodiment, the first clutch 4 is a wet friction clutch, such as... Figure 8 As shown, the device includes a housing 41 disposed between the second-gear drive gear 12 and the main motor M1, and a first friction pair 42, a relative rotation actuator, a second friction pair 43, and a first electromagnet 44 sequentially disposed within the housing 41. The housing 41 is connected to the second-gear drive gear 12. The driving friction plate of the first friction pair 42 is connected to the first input shaft 1a, and the driven friction plate is connected to the housing 41. The driving friction plate of the second friction pair 43 is connected to the housing 41, and the driven friction pair is connected to the relative rotation actuator. When the first electromagnet 44 is energized, the driving and driven friction plates of the second friction pair 43 press against each other, thereby causing the relative rotation actuator to rotate relative to each other and generate axial movement to press against the driving and driven friction plates of the first friction pair 42, causing the second-gear drive gear 12 to engage with the first input shaft 1a. When the first electromagnet 44 is de-energized, the second-gear drive gear 12 disengages from the first input shaft 1a.

[0046] In this embodiment, the aforementioned relative rotation actuator is a ball-bearing ramp actuator, comprising a first cam disk 45, a second cam disk 46, and a plurality of balls 47 arranged circumferentially between them. Multiple circumferentially distributed arc-shaped raceway grooves are formed on the opposite end faces of the first cam disk 45 and the second cam disk 46. The depth of the raceway grooves varies circumferentially. Each ball 47 is sandwiched between one raceway groove of the first cam disk 45 and one raceway groove of the second cam disk 46. Without external force, the ball 47 is sandwiched at the deepest point of the two raceway grooves. The two cam disks rotate synchronously through the balls 47, and the relative rotation of the two cam disks causes the balls 47 to roll in the raceway grooves, resulting in axial relative displacement between the two cam disks. The first cam disk 45 is circumferentially fixed to the first input shaft 1a and adjacent to the first friction pair 42. The second cam disk 46 is axially fixedly fitted onto the first input shaft 1a and connected to the driven friction plate of the second friction pair 43. Therefore, the mutual pressing of the driving and driven friction plates of the second friction pair 43 causes the second cam disk 46 to connect with the housing 41 and rotate relative to the first cam disk 45, thereby causing the first cam disk 45 to move axially and press against the driving and driven friction plates of the first friction pair 42. Replacing the ball-bearing ramp actuator with other types of relative rotation actuators is also within the scope of this invention.

[0047] like Figure 9 As shown, in this embodiment, the second clutch 5 includes an electromagnetic thruster, a clutch disc 51, and a return spring 52, sequentially disposed between the auxiliary motor M2 and the first gear drive gear 11. The clutch disc 51 is circumferentially fixed to the second input shaft 1b and rotates synchronously with the second input shaft 1b. A toothed locking connection structure is provided between the clutch disc 51 and the first gear drive gear 11, which can be end face teeth or inner and outer ring teeth. The switching on and off of the electromagnetic thruster can cause the clutch disc 51 to move axially along the second input shaft 1b and lock or disengage from the first gear drive gear 11, thereby causing the first gear drive gear 11 to engage or disengage from the second input shaft 1b. The return spring 52 abuts against the clutch disc 51 and the first gear drive gear 11, and always applies a force to the clutch disc 51 to make it tend to move away from the first gear drive gear 11. Specifically, the aforementioned electromagnetic thruster includes a coaxially arranged annular housing 53, a second electromagnet 54, an annular support sleeve 55, and a sliding sleeve 56. The second electromagnet 54 is placed inside the annular housing 53, and the annular support sleeve 55 is located on the radially inner side of the annular housing 53. A bearing is provided between the annular support sleeve 55 and the second input shaft 1b. The sliding sleeve 56 is axially movable between the annular housing 53 and the annular support sleeve 55 and abuts against the clutch disc 51. The energization of the second electromagnet 54 can cause the sliding sleeve 56 to move axially, thereby pushing the clutch disc 51 to move and lock into connection with the first gear drive gear 11.

[0048] Finally, it is understood that those skilled in the art can make various other corresponding changes and modifications based on the technical concept of this invention, and all such changes and modifications should fall within the protection scope of the claims of this invention.

Claims

1. A dual-motor multi-mode power system, comprising a drive motor, an input shaft assembly, an intermediate shaft assembly, a first clutch, and a second clutch, wherein the input shaft assembly includes an input shaft and a first-speed drive gear and a second-speed drive gear mounted on the input shaft, the intermediate shaft assembly includes an intermediate shaft parallel to the input shaft and a first-speed driven gear and a second-speed driven gear fixedly connected to the intermediate shaft, the first-speed driven gear meshing with the first-speed drive gear, the second-speed driven gear meshing with the second-speed drive gear, and the intermediate shaft assembly driving the wheels of an electric vehicle via a differential, characterized in that: The drive motor includes a main motor and an auxiliary motor symmetrically arranged at both ends of the input shaft. The input shaft includes a first input shaft and a second input shaft rotatably connected. The other end of the first input shaft is connected to the main motor, and the other end of the second input shaft is connected to the auxiliary motor. The first gear drive gear is mounted on the first input shaft via a one-way clutch. The one-way clutch is configured to allow the first gear drive gear to rotate in the forward direction relative to the first input shaft, and to lock it in the reverse direction. The second gear drive gear is loosely fitted on the first input shaft. Engaging or disengaging the first clutch causes the second gear drive gear to engage or disengage from the first input shaft, and engaging or disengaging the second clutch causes the first gear drive gear to engage or disengage from the second input shaft. The dual-motor multi-mode power system has six operating modes, including: In the first gear drive mode of the main motor, the main motor starts and rotates forward, the auxiliary motor stops, the first clutch and the second clutch are both disengaged, and the power of the main motor is transmitted to the first gear drive gear through the first input shaft and the one-way clutch. The first gear drive gear drives the wheels forward at low speed through the intermediate shaft assembly and the differential. In the first gear drive mode of the auxiliary motor, the main motor stops and the auxiliary motor starts to rotate forward. The first clutch disengages and the second clutch engages. The power of the auxiliary motor is transmitted to the first gear drive gear through the second input shaft and the second clutch. The one-way clutch overruns and unlocks, and the first input shaft slips with the first gear drive gear. The first gear drive gear drives the wheels forward at low speed through the intermediate shaft assembly and the differential. In the dual-motor first-gear drive mode, both the main motor and the auxiliary motor start rotating forward. The first clutch disengages and the second clutch engages. The power of the main motor is transmitted to the first-gear drive gear via the first input shaft and the one-way clutch. The power of the auxiliary motor is transmitted to the first-gear drive gear via the second input shaft and the second clutch. The power of the main and auxiliary motors is superimposed to form the first combined power. The first combined power drives the wheels forward at low speed via the intermediate shaft assembly and the differential. In the second-speed drive mode of the main motor, the main motor starts and rotates forward, the auxiliary motor stops, the first clutch engages, the second clutch disengages, the power of the main motor is transmitted to the second-speed drive gear through the first input shaft and the first clutch, the one-way clutch overruns and unlocks, the first-speed drive gear spins freely on the first input shaft, and the second-speed drive gear drives the wheels forward at high speed through the intermediate shaft assembly and differential. In the dual-motor two-speed drive mode, the main motor starts rotating forward, and the auxiliary motor starts rotating at high speed. Both the first and second clutches are engaged. The power of the main motor is transmitted to the second-speed drive gear through the first input shaft and the first clutch, and the power of the auxiliary motor is transmitted to the first-speed drive gear through the second input shaft and the second clutch, driving the first-speed drive gear to rotate at high speed. The one-way clutch is overrun and unlocked, and the first-speed drive gear slips off the first input shaft. The power of the main and auxiliary motors is superimposed into a second combined power through the transmission coupling of the first-speed drive gear, the intermediate shaft assembly, and the second-speed drive gear. The second combined power drives the wheels forward at high speed through the intermediate shaft assembly and the differential. In the dual-motor reverse drive mode, both the main motor and the auxiliary motor start and reverse. The first clutch disengages and the second clutch engages. The power of the auxiliary motor is transmitted to the first gear drive gear through the second input shaft and the second clutch, causing the first gear drive gear to reverse. The main motor drives the first input shaft to rotate in the opposite direction, preventing the auxiliary motor from driving the main motor to rotate through the first gear drive gear and the one-way clutch. The first gear drive gear drives the wheels to reverse at low speed through the intermediate shaft assembly and the differential. It also includes a control system for responding to a request from the vehicle controller to control the dual-motor multi-mode powertrain to drive the vehicle in one of the six operating modes described above.

2. The dual-motor multi-mode power system according to claim 1, characterized in that: The first clutch includes a housing disposed between the second-gear drive gear and the main motor, and a first friction pair, a relative rotation actuator, a second friction pair, and a first electromagnet sequentially disposed within the housing. The housing is connected to the second-gear drive gear. The driving friction plate of the first friction pair is connected to the first input shaft, and the driven friction plate is connected to the housing. The driving friction plate of the second friction pair is connected to the housing, and the driven friction pair is connected to the relative rotation actuator. When the first electromagnet is energized, the driving and driven friction plates of the second friction pair press against each other, thereby causing the relative rotation actuator to rotate relative to each other and generate axial movement to press against the driving and driven friction plates of the first friction pair, thus engaging the second-gear drive gear with the first input shaft. When the first electromagnet is de-energized, the second-gear drive gear disengages from the first input shaft.

3. The dual-motor multi-mode power system according to claim 1, characterized in that: The second clutch includes an electromagnetic thruster, a clutch disc, and a return spring, which are sequentially arranged between the auxiliary motor and the first gear drive gear. The clutch disc is circumferentially fixed to the second input shaft and rotates synchronously with the second input shaft. A toothed locking connection structure is provided between the clutch disc and the first gear drive gear. The on and off state of the electromagnetic thruster can cause the clutch disc to move axially along the second input shaft and lock or disengage from the first gear drive gear, thereby causing the first gear drive gear to engage or disengage from the second input shaft. The return spring applies a force to the clutch disc, causing it to move away from the first gear drive gear.

Images