A power system for an electric vehicle

Abstract

The application provides a power system of an electric vehicle. The power system of the electric vehicle comprises a first driving motor, a second driving motor, a controller, a two-gear gearbox, a drive axle, a single-stage speed reducer and a jaw clutch. When the controller receives a driving mode starting instruction of the electric vehicle, the controller controls the two-gear gearbox, the jaw clutch and the first driving motor and / or the second driving motor, and the driving motor outputs power to the wheels through the drive axle. When the controller receives a braking mode starting instruction of the electric vehicle, the controller controls the working mode of the first driving motor and / or the second driving motor, and the first driving motor and / or the second driving motor applies braking torque to the wheels through the drive axle, so that the vehicle gradually slows down. The scheme of the application can make the vehicle more flexible to adapt to different road conditions, and better driving comfort and economy can be obtained.

Description

Technical Field

[0001] This invention relates to the field of new energy vehicles, and in particular to a power system for an electric vehicle. Background Technology

[0002] A powertrain system with a single drive motor and a single-stage reducer is widely used in the powertrain systems of pure electric vehicles. Although this powertrain system is simple and easy to lay out, it requires high power from the drive motor to meet the power requirements of acceleration, climbing, and high-speed operation. Moreover, the operating mode of this powertrain system is singular, which leads to low efficiency of the drive motor under low load conditions. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide a power system for an electric vehicle. The dual-motor power system enables the vehicle to adapt more flexibly to different road conditions and achieve better driving comfort and economy.

[0004] To solve the above-mentioned technical problems, the technical solution of the present invention is as follows:

[0005] Embodiments of the present invention provide a power system for an electric vehicle, comprising:

[0006] First drive motor;

[0007] A second drive motor connected to the first drive motor;

[0008] A controller that is electrically connected to the first drive motor and the second drive motor respectively;

[0009] A two-speed gearbox connected to the first drive motor;

[0010] The drive axle of the two-speed gearbox is connected via a drive shaft;

[0011] A single-stage reducer connected to the second drive motor;

[0012] The single-stage reducer is connected to the two-speed gearbox via a claw clutch, and the claw clutch engages on the output shaft of the two-speed gearbox.

[0013] Wherein, the controller receives a drive mode activation command from the electric vehicle, at least one of the first drive motor and the second drive motor, as well as the two-speed gearbox and the claw clutch, output power to the wheels through the drive axle; or

[0014] When the controller receives a braking mode activation command from the electric vehicle, it controls the operating mode of the first drive motor and / or the second drive motor. The first drive motor and / or the second drive motor apply braking torque to the wheels through the drive axle, causing the vehicle to gradually decelerate.

[0015] Optionally, the two-speed gearbox further includes a synchronizer located within the two-speed gearbox and meshing with the gears within the two-speed gearbox.

[0016] Optionally, the drive axle includes a main reducer, which is connected to the output shaft of the two-speed gearbox via a drive shaft.

[0017] Optionally, the drive axle further includes a differential connected to the driven large gear ring of the main reducer, the differential being connected to the wheels via half-shafts.

[0018] Optionally, when the controller receives the first drive mode start command of the electric vehicle, it controls the two-speed gearbox to be in the first or second gear working state, the claw clutch to be in the disengaged state, the second drive motor to be in the stationary state, and the first drive motor to output power to the wheels through the drive axle.

[0019] Optionally, when the controller receives the second drive mode start command of the electric vehicle, it controls the two-speed gearbox to be in neutral, the claw clutch to be engaged, the first drive motor to be stationary and not working, and the second drive motor to output power to the wheels through the drive axle.

[0020] Optionally, when the controller receives the third drive mode start command of the electric vehicle, it controls the two-speed gearbox to be in first or second gear, the claw clutch to be engaged, and both the first drive motor and the second drive motor to be in operation, outputting power to the wheels through the drive axle.

[0021] Optionally, when the controller receives the first braking mode activation command of the electric vehicle, the two-speed transmission is in first or second gear, the claw clutch is disengaged, the second drive motor is stationary, the controller controls the first drive motor to operate in generator mode, and the first drive motor applies braking torque to the wheels through the drive axle.

[0022] Optionally, when the controller receives the second braking mode activation command of the electric vehicle, the two-speed transmission is in neutral, the claw clutch is engaged, the first drive motor is stationary, the controller controls the second drive motor to operate in generator mode, and the second drive motor applies braking torque to the wheels through the drive axle.

[0023] Optionally, when the controller receives the third braking mode activation command of the electric vehicle, the two-speed transmission is in first or second gear, the claw clutch is engaged, the controller controls the first drive motor and the second drive motor to be in generator state, and the first drive motor and the second drive motor apply braking torque to the wheels through the drive axle.

[0024] The above-described solution of the present invention has at least the following beneficial effects:

[0025] The electric vehicle power system described in the above-mentioned solution of the present invention adopts an integrated dual-motor power system. This dual-motor configuration can provide the vehicle with multiple operating modes, making the vehicle more flexible to adapt to different road conditions and obtain better driving comfort and economy. The space occupied by this integrated dual-motor power system in the vehicle is not much different from that of a single-motor power system, and it is superior to the front and rear distributed dual-motor system in terms of cost. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the power system of an electric vehicle provided in an embodiment of the present invention;

[0027] Figure 2 This is a power transmission route diagram of the first drive mode of the electric vehicle's power system provided in an embodiment of the present invention;

[0028] Figure 3 This is a power transmission route diagram of the first drive mode of the electric vehicle's power system provided in an embodiment of the present invention;

[0029] Figure 4 This is a power transmission route diagram of the second drive mode of the electric vehicle's power system provided in an embodiment of the present invention;

[0030] Figure 5 This is a power transmission route diagram for the third drive mode of the electric vehicle's power system provided in an embodiment of the present invention;

[0031] Figure 6 This is a power transmission route diagram for the third drive mode of the electric vehicle's power system provided in an embodiment of the present invention;

[0032] Figure 7This is a power transmission route diagram of the first braking mode of the power system of an electric vehicle provided in an embodiment of the present invention;

[0033] Figure 8 This is a power transmission route diagram of the first braking mode of the power system of an electric vehicle provided in an embodiment of the present invention;

[0034] Figure 9 This is a power transmission route diagram for the second braking mode of the electric vehicle's power system provided in an embodiment of the present invention;

[0035] Figure 10 This is a power transmission route diagram for the third braking mode of the electric vehicle's power system provided in an embodiment of the present invention;

[0036] Figure 11 This is a power transmission route diagram for the third braking mode of the electric vehicle's power system provided in an embodiment of the present invention.

[0037] Explanation of reference numerals in the attached figures:

[0038] 11. First drive motor; 12. Two-speed gearbox; 121. Synchronizer; 21. Second drive motor; 22. Single-stage reducer; 23. Claw clutch; 3. Main reducer; 4. Differential; 5. Wheel. Detailed Implementation

[0039] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

[0040] like Figure 1 As shown, an embodiment of the present invention provides a power system for an electric vehicle, comprising:

[0041] First drive motor 11;

[0042] The second drive motor 21 is connected to the first drive motor 11;

[0043] A controller that is electrically connected to the first drive motor 11 and the second drive motor 21 respectively;

[0044] A two-speed gearbox 12 connected to the first drive motor 11; a drive axle connected to the two-speed gearbox 12 via a drive shaft;

[0045] A single-stage reducer 22 is connected to the second drive motor 21; the single-stage reducer 22 is connected to the two-speed gearbox 12 via a claw clutch 23, and the claw clutch 23 engages on the output shaft of the two-speed gearbox 12.

[0046] The controller receives a drive mode activation command from the electric vehicle and controls at least one of the first drive motor 11 and the second drive motor 21, as well as the two-speed gearbox 12 and the claw clutch 23, to output power to the wheels 5 through the drive axle; or

[0047] When the controller receives the braking mode activation command of the electric vehicle, it controls the working mode of the first drive motor 11 and / or the second drive motor 21. The first drive motor 11 and / or the second drive motor 21 apply braking torque to the wheels through the drive axle, so that the vehicle gradually decelerates.

[0048] The electric vehicle power system proposed in this embodiment of the invention is a dual-motor power system. A second drive motor 21 with a smaller power than the first drive motor 11 is arranged on the output shaft of the two-speed gearbox 12, which effectively solves the problems of single working mode and low working efficiency of drive motor under low speed and low load conditions. In addition, this dual-motor configuration can eliminate the power interruption problem when the two-speed gearbox 12 shifts. Since the second drive motor 21 is a permanent magnet synchronous motor, the claw clutch 23 can prevent the second drive motor 21 from generating drag loss, and at the same time, the claw clutch 23 can increase the flexibility of the configuration.

[0049] In an optional embodiment of the present invention, the two-speed gearbox 12 further includes a synchronizer 121, which is located within the two-speed gearbox 12 and meshes with the gears within the two-speed gearbox 12. The two-speed gearbox 12 is an AMT automatic gearbox. The synchronizer 121 is located on the output shaft within the two-speed gearbox 12. During gear shifting, the shift fork pushes the engagement sleeve to press the synchronizer 121 into engagement with the gear, thereby achieving power output at different gears. Since the rotational speed of the engagement sleeve is different from the rotational speed of the gear to be engaged, the synchronizer 121 can synchronize the rotational speeds of the engagement sleeve and the gear before engagement, achieving smooth gear shifting.

[0050] In an optional embodiment of the present invention, the drive axle includes a main reducer 3, which is connected to the output shaft of the two-speed gearbox 12 via a transmission shaft. The main reducer 3 is composed of one or more pairs of bevel gears, in which the small gear drives the large gear to rotate, thereby achieving speed reduction and torque increase. At the same time, the torque transmitted from the transmission shaft around the longitudinal axis is changed to the torque required by the drive axle around the transverse axis.

[0051] In an optional embodiment of the present invention, the drive axle further includes a differential 4 connected to the driven large gear ring of the main reducer 3, the differential 4 being connected to the wheel 5 via a half-shaft; the differential 4 receives power from the main reducer 3 and transmits the power to the wheel via the half-shaft, the differential 4 can realize different rotational speeds of the inner and outer wheels, ensuring that the inner and outer wheels turn at different speeds.

[0052] Based on the structure of this dual-motor power system, the working modes of the AMT and the claw clutch can be divided into the following three types:

[0053]

[0054]

[0055] In an optional embodiment of the present invention, when the controller receives the first drive mode start command of the electric vehicle, it controls the two-speed gearbox 12 to be in the first or second gear working state, the claw clutch 23 to be in the disengaged state, the second drive motor 21 to be in the stationary state, and the first drive motor 11 to output power to the wheels through the drive axle.

[0056] like Figure 2 As shown, the two-speed gearbox 12 is in first gear. The coupling sleeve on the output shaft of the two-speed gearbox 12 is engaged with the first gear through the synchronizer 121. The first drive motor 11 operates in motor mode, converting electrical energy into mechanical energy and outputting it to the input shaft of the two-speed gearbox 12. After a series of gear transmissions, the power is output from the output shaft through the first gear. The power output by the two-speed gearbox 12 is transmitted to the main reducer 3 via the transmission shaft. The main reducer 3 transmits the power to the differential 4, which drives the half-shaft to rotate, thereby causing the wheel connected to the half-shaft to rotate. At this time, the power transmission route is as shown in S11.

[0057] like Figure 3 As shown, the two-speed gearbox 12 is in second gear. The coupling sleeve on the output shaft of the two-speed gearbox 12 engages with the gear of the second gear position through the synchronizer 121. The first drive motor 11 operates in motor mode, converting electrical energy into mechanical energy and outputting it to the input shaft of the two-speed gearbox 12. After a series of gear transmissions, the power is output from the output shaft through the second gear position. The power output by the two-speed gearbox 12 is transmitted to the main reducer 3 via the transmission shaft. The main reducer 3 transmits the power to the differential 4, which drives the half-shaft to rotate, thereby causing the wheel connected to the half-shaft to rotate. At this time, the power transmission route is as shown in S12.

[0058] In an optional embodiment of the present invention, when the controller receives the second drive mode start command of the electric vehicle, it controls the two-speed gearbox 12 to be in neutral, the claw clutch 23 to be engaged, the first drive motor 11 to be stationary and not working, and the second drive motor 21 to output power to the wheels through the drive axle.

[0059] like Figure 4 As shown, the first drive motor 11 does not output power, and the second drive motor operates in motor mode, converting electrical energy into mechanical energy and outputting it to the single-stage reducer 22. After a series of rotations, the gear set inside the single-stage reducer 22 outputs power through the output shaft. The first end of the claw clutch 23 is connected to the output shaft of the single-stage reducer 23, and the second end is connected to the output shaft of the two-speed gearbox 12. Since the claw clutch is in a meshed state, the power output from the single-stage reducer 22 is transmitted to the drive shaft through the output shaft of the two-speed gearbox 12. The drive shaft drives the main reducer 3 to rotate, and the main reducer 3 transmits power to the differential 4. The differential 4 drives the half-shaft and then drives the wheel connected to the half-shaft to rotate. At this time, the power transmission route is as shown in S2.

[0060] In an optional embodiment of the present invention, when the controller receives the third drive mode start command of the electric vehicle, it controls the two-speed gearbox 12 to be in the first or second gear working state, the claw clutch 23 to be in the engaged state, and the first drive motor 11 and the second drive motor 21 are both in the working state, outputting power to the wheels through the drive axle.

[0061] like Figure 5 As shown, both the first drive motor 11 and the second drive motor 21 are in electric motor mode, and the two-speed gearbox 12 is in first gear. The coupling sleeve on the output shaft of the two-speed gearbox 12 engages with the gear of the first gear through the synchronizer 121. The claw clutch 23 connects the output shaft of the two-speed gearbox 12 to the output shaft of the single-stage reducer 22. The power output from the first drive motor 11 and the second drive motor 21 is combined onto the output shaft of the two-speed gearbox 12 and transmitted to the drive axle via the transmission shaft, thereby driving the wheels to rotate. At this time, the power transmission route is as shown in S31.

[0062] like Figure 6As shown, both the first drive motor 11 and the second drive motor 21 are in electric motor mode, and the two-speed gearbox 12 is in second gear. The coupling sleeve on the output shaft of the two-speed gearbox 12 engages with the gear of the second gear through the synchronizer 121. The claw clutch 23 connects the output shaft of the two-speed gearbox 12 to the output shaft of the single-stage reducer 22. The power output from the first drive motor 11 and the second drive motor 21 is combined onto the output shaft of the two-speed gearbox 12 and transmitted to the drive axle via the transmission shaft, thereby driving the wheels to rotate. At this time, the power transmission route is as shown in S32.

[0063] In an optional embodiment of the present invention, when the controller receives the first braking mode start command of the electric vehicle, the two-speed gearbox 12 is in the first or second gear working state, the claw clutch 23 is in the disengaged state, the second drive motor 21 is in the stationary state, the controller controls the first drive motor 11 to work in the generator state, and the first drive motor 11 applies braking torque to the wheels through the drive axle.

[0064] like Figure 7 , Figure 8 As shown, when the vehicle is in normal driving mode and the braking mode is activated, the first drive motor 11 stops outputting driving force to the wheels. However, the wheels do not stop immediately due to inertia, but continue to move forward. At this time, the wheels output power to the drive axle, transmission shaft, two-speed gearbox 12 and the first drive motor 11 connected to them, driving the gears inside to rotate. The power transmission route at this time is shown in S41 and S42. Correspondingly, the first drive motor 11, two-speed gearbox 12, transmission shaft and drive axle apply a reaction force, i.e., braking torque, to the wheels. The wheels gradually decelerate under the combined action of braking torque and road friction.

[0065] In an optional embodiment of the present invention, when the controller receives the second braking mode start command of the electric vehicle, the two-speed gearbox 12 is in neutral and not working, the claw clutch 23 is engaged, the first drive motor 11 is stationary, the controller controls the second drive motor 21 to work in the generator state, and the second drive motor 21 applies braking torque to the wheels through the drive axle.

[0066] like Figure 9As shown, when the vehicle is in normal driving mode and the braking mode is activated, the second drive motor 21 stops outputting driving force to the wheels. However, the wheels do not stop immediately due to inertia, but continue to move forward. At this time, the wheels output power to the drive axle, drive shaft, claw clutch 23, single-stage reducer 22 and second drive motor 21 connected to them, driving the gears inside to rotate. The power transmission route at this time is shown in S5. Correspondingly, the second drive motor 21, single-stage reducer 22, drive shaft and drive axle apply a reaction force, i.e. braking torque, to the wheels. The wheels gradually decelerate under the combined action of braking torque and road friction.

[0067] In an optional embodiment of the present invention, when the controller receives the third braking mode start command of the electric vehicle, the two-speed gearbox 12 is in the first or second gear working state, the claw clutch 23 is in the engaged state, and the controller controls the first drive motor 11 and the second drive motor 21 to be in the power generation state. The first drive motor 11 and the second drive motor 21 apply braking torque to the wheels through the drive axle.

[0068] like Figure 10 , Figure 11 As shown, when the vehicle is in normal driving mode and the braking mode is activated, the first drive motor 11 and the second drive motor 21 stop outputting driving force to the wheels. However, the wheels do not stop immediately due to inertia, but continue to move forward. At this time, the wheels output power to the drive axle, drive shaft, two-speed gearbox 12, first drive motor 11, claw clutch 23, single-stage reducer 22 and second drive motor 21 connected to them, driving the gears inside to rotate. The power transmission route at this time is shown in S61 and S62. Correspondingly, the first drive motor 11, two-speed gearbox 12, second drive motor 21, single-stage reducer 22, drive shaft and drive axle apply a reaction force, i.e., braking torque, to the wheels. The wheels gradually decelerate under the combined action of braking torque and road friction.

[0069] The above embodiments of the present invention provide electric vehicles equipped with dual drive motors that offer greater flexibility to adapt to different driving conditions compared to electric vehicles equipped with a single drive motor, thereby achieving better driving comfort and economy. This integrated dual-motor powertrain structure occupies roughly the same amount of space within the vehicle as a single-motor powertrain system, and is more cost-effective than a front-rear distributed dual-motor system.

[0070] The above description represents the preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A power system for an electric vehicle, characterized in that, include: First drive motor (11); A second drive motor (21) connected to the first drive motor (11); A controller that is electrically connected to the first drive motor (11) and the second drive motor (21) respectively; A two-speed gearbox (12) connected to the first drive motor (11); The drive axle of the two-speed gearbox (12) is connected by a drive shaft; A single-stage reducer (22) connected to the second drive motor (21); The single-stage reducer (22) is connected to the two-speed gearbox (12) via a claw clutch (23), and the claw clutch (23) engages on the output shaft of the two-speed gearbox (12). The controller receives a drive mode start command from the electric vehicle and controls at least one of the first drive motor (11) and the second drive motor (21), as well as the two-speed gearbox (12) and the claw clutch (23), to output power to the wheels (5) through the drive axle; or When the controller receives the braking mode start command of the electric vehicle, it controls the working mode of the first drive motor (11) and / or the second drive motor (21). The first drive motor (11) and / or the second drive motor (21) apply braking torque to the wheels through the drive axle, so that the vehicle gradually decelerates. When the controller receives the second drive mode start command of the electric vehicle, it controls the two-speed gearbox (12) to be in neutral, the claw clutch (23) to be engaged, the first drive motor (11) to be stationary, and the second drive motor (21) to output power to the wheel (5) through the drive axle.

2. The power system for an electric vehicle according to claim 1, characterized in that, The two-speed gearbox (12) also includes a synchronizer (121), which is located inside the two-speed gearbox (12) and meshes with the gears inside the two-speed gearbox (12).

3. The power system for an electric vehicle according to claim 1, characterized in that, The drive axle includes a main reducer (3), which is connected to the output shaft of the two-speed gearbox (12) via a drive shaft.

4. The power system of the electric vehicle according to claim 3, characterized in that, The drive axle also includes a differential (4) connected to the driven large gear ring of the main reducer (3), and the differential (4) is connected to the wheel (5) via a half shaft.

5. The power system for an electric vehicle according to claim 4, characterized in that, When the controller receives the first drive mode start command of the electric vehicle, it controls the two-speed gearbox (12) to be in the first or second gear working state, the claw clutch (23) to be in the disengaged state, the second drive motor (21) to be in the stationary state, and the first drive motor (11) to output power to the wheel (5) through the drive axle.

6. The power system of the electric vehicle according to claim 4, characterized in that, When the controller receives the third drive mode start command of the electric vehicle, it controls the two-speed gearbox (12) to be in the first or second gear working state, the claw clutch (23) to be in the engaged state, the first drive motor (11) and the second drive motor (21) are both in the working state, and output power to the wheel (5) through the drive axle.

7. The power system for an electric vehicle according to claim 4, characterized in that, When the controller receives the first braking mode start command of the electric vehicle, the two-speed gearbox (12) is in the first or second gear working state, the claw clutch (23) is in the disengaged state, the second drive motor (21) is in the stationary state, the controller controls the first drive motor (11) to work in the power generation state, and the first drive motor (11) applies braking torque to the wheel (5) through the drive axle.

8. The power system of the electric vehicle according to claim 4, characterized in that, When the controller receives the second braking mode start command of the electric vehicle, the two-speed gearbox (12) is in neutral, the claw clutch (23) is in engagement, the first drive motor (11) is in a stationary state, the controller controls the second drive motor (21) to work in the power generation state, and the second drive motor (21) applies braking torque to the wheel (5) through the drive axle.

9. The power system of the electric vehicle according to claim 4, characterized in that, When the controller receives the third braking mode start command of the electric vehicle, the two-speed gearbox (12) is in the first or second gear working state, the claw clutch (23) is in the engagement state, the controller controls the first drive motor (11) and the second drive motor (21) to be in the power generation state, and the first drive motor (11) and the second drive motor (21) apply braking torque to the wheel (5) through the drive axle.

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