Electric motorcycle dual-motor drive device and dual-motor drive strategy

Abstract

A dual-motor drive device for an electric motorcycle includes a reduction gear, a main drive sprocket coaxially arranged with the reduction gear, a transmission chain matched with the main drive sprocket, a first drive gear meshing with the reduction gear, an intermediate gear coaxially arranged with the first drive gear, a second drive gear meshing with the intermediate gear, an overrunning clutch for realizing power transmission or separation between the intermediate gear and the first drive gear, a first drive motor for driving the first drive gear to rotate, and a second drive motor for driving the second drive gear to rotate. In this way, the reduction combinations of the motors are different under different riding conditions, so that the use efficiency of the motors is high at each stage, automatic operation, no sense of frustration, wide speed coverage, taking into account both acceleration and climbing, increasing the cruising range and having a redundant protection function. The present invention also provides a dual-motor drive strategy for an electric motorcycle.

Description

Technical Field

[0001] The invention relates to the technical field of electric motorcycle power and control, in particular to an electric motorcycle dual-motor driving device and a dual-motor driving strategy thereof. Background Art

[0002] The "Safety Technical Specifications for Electric Bicycles" came into effect on April 15, 2019. It stipulates that electric bicycles must have a pedal riding function, a maximum speed of ≤25km / h, a motor power of ≤400w, a battery voltage of ≤48v, ​​and a vehicle mass of ≤55kg; electric mopeds have a maximum speed of ≤50km / h, battery specifications are not restricted, and the vehicle mass can be ≥55kg. They are motor vehicles and are not allowed to carry passengers; electric motorcycles have a maximum speed of >50km / h, battery specifications are not restricted, and the vehicle mass can be ≥55kg. They are motor vehicles and are allowed to carry passengers, and can carry one adult.

[0003] The existing electric motorcycles are driven by a single motor, and a controller controls the operation of the motor. Usually, a mechanical gearbox or CVT continuously variable transmission is configured. When using a mechanical gearbox, there will be a sense of frustration when shifting gears, and the shifting operation requires hands or feet; when using a CVT continuously variable transmission, the working efficiency is low, and the working efficiency is less than 80% in an ideal state, and less than 70% in actual tests, and the cost is also high. Summary of the invention

[0004] In view of this, the present invention provides an electric motorcycle dual-motor drive device and a dual-motor drive strategy having different motor deceleration combinations under different riding conditions, so as to solve the above problems, with high motor utilization efficiency in each stage, automatic operation, no sense of frustration, wide speed coverage, taking into account both acceleration and climbing, increased cruising range and redundant protection function.

[0005] A dual-motor drive device for an electric motorcycle comprises a reduction gear, a main transmission sprocket coaxially arranged with the reduction gear, a transmission chain matched with the main transmission sprocket, a first driving gear meshed with the reduction gear, an intermediate gear coaxially arranged with the first driving gear, a second driving gear meshed with the intermediate gear, an overrunning clutch for realizing power transmission or separation between the intermediate gear and the first driving gear, a first driving motor for driving the first driving gear to rotate, and a second driving motor for driving the second driving gear to rotate; a first end of the transmission chain meshes with the main transmission sprocket, and a second end meshes with a driven sprocket fixed to the rear wheel of the electric motorcycle; the first driving gear, the intermediate gear, the second driving gear, the first driving motor and the second driving motor are all located on a side of the reduction gear away from the driven sprocket.

[0006] Furthermore, a first encoder is disposed on the first drive motor, and both the first drive motor and the first encoder are connected to a first controller.

[0007] Furthermore, a second encoder is disposed on the second drive motor, and both the second drive motor and the second encoder are connected to a second controller.

[0008] Furthermore, a whole machine controller is provided, and the whole machine controller communicates with both the first controller and the second controller.

[0009] Furthermore, the first controller, the second controller or the whole machine controller reads the operating current of the first drive motor or the second drive motor and calculates the output torque according to the operating current.

[0010] Further, the second controller serves as a master controller and the first controller serves as a slave controller; or the first controller serves as a master controller and the second controller serves as a slave controller; the master controller is connected or communicates with the slave controller.

[0011] Furthermore, a brake is provided on the side of the reduction gear facing away from the main transmission sprocket.

[0012] Furthermore, the first drive motor, the second drive motor, the reduction gear, the first drive gear, the intermediate gear and the second drive gear are all arranged between the front wheel and the rear wheel of the electric motorcycle and fixed on the straddle frame of the electric motorcycle, and the main drive sprocket is connected to the driven sprocket through a transmission chain.

[0013] Furthermore, the reduction ratio between the reduction gear and the first driving gear is 1:3 to 1:5, and the rotation speed of the first driving gear and the intermediate gear is the same; the reduction ratio between the intermediate gear and the second driving gear is less than 1:1 and greater than 1:2.

[0014] A dual-motor driving strategy for an electric motorcycle, using the dual-motor driving device for an electric motorcycle as described above to drive the electric motorcycle, comprises the following steps: Step S1: when the running speed of the electric motorcycle is greater than 0 km / h and less than 50 km / h, the second controller controls the second drive motor to work, and the first controller controls the first drive motor to idle; Step S2: when the running speed of the electric motorcycle is greater than or equal to 50 km / h and less than 120 km / h, and the output torque is less than a predetermined torque value, and the working current of the second drive motor is less than a predetermined current value, the second controller controls the second drive motor to maintain working, and the first controller controls the first drive motor to idle; Step S3: when the running speed of the electric motorcycle is greater than or equal to 50 km / h and less than 120 km / h, and the output torque is greater than or equal to the predetermined torque value or the working current of the second drive motor is greater than or equal to the predetermined current value, the second controller controls the second drive motor to maintain operation, and the first controller controls the first drive motor to participate in the operation; step S4: when the running speed of the electric motorcycle is greater than or equal to 120km / h, the first controller controls the first drive motor to work, the second controller controls the second drive motor not to work, and at the same time controls the overrunning clutch to disconnect the power transmission between the intermediate gear and the first drive gear; step S5: when one of the first controller or the second controller fails, the corresponding first drive motor or the second drive motor is controlled to idle, and no resistance is generated to the power transmission; at the same time, the other controller enters the working state and works within the predetermined current range.

[0015] Compared with the prior art, the dual-motor drive device of the electric motorcycle of the present invention includes a reduction gear, a main drive sprocket coaxially arranged with the reduction gear, a transmission chain matched with the main drive sprocket, a first drive gear meshed with the reduction gear, an intermediate gear coaxially arranged with the first drive gear, a second drive gear meshed with the intermediate gear, an overrunning clutch for realizing power transmission or separation between the intermediate gear and the first drive gear, a first drive motor for driving the first drive gear to rotate, and a second drive motor for driving the second drive gear to rotate; the first end of the transmission chain is meshed with the main drive sprocket, and the second end is meshed with a driven sprocket. In this way, the motor has different reduction combinations under different riding conditions, so that the motor has a higher efficiency in each stage, automatic operation, no sense of frustration, a wide speed coverage, taking into account acceleration and climbing, increasing the cruising range and having a redundant protection function. The present invention also provides a dual-motor drive strategy for an electric motorcycle. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The embodiments of the present invention are described below in conjunction with the accompanying drawings, wherein:

[0017] Figure 1 This is a first side schematic diagram of the dual-motor drive device for an electric motorcycle provided by the present invention.

[0018] Figure 2 This is a second side schematic diagram of the dual-motor drive device for an electric motorcycle provided by the present invention. DETAILED DESCRIPTION

[0019] The specific embodiments of the present invention are further described in detail below based on the accompanying drawings. It should be understood that the description of the embodiments of the present invention herein is not intended to limit the protection scope of the present invention.

[0020] Please refer to Figure 1 The dual-motor driving device of an electric motorcycle provided by the present invention comprises a reduction gear 10, a main transmission sprocket 20 coaxially arranged with the reduction gear 10, a transmission chain 30 matched with the main transmission sprocket 20, a first driving gear 40 meshing with the reduction gear 10, an intermediate gear 50 coaxially arranged with the first driving gear 40, a second driving gear 60 meshing with the intermediate gear 50, an overrunning clutch 51 for realizing power transmission or separation between the intermediate gear 50 and the first driving gear 40, a first driving motor 41 for driving the first driving gear 40 to rotate, and a second driving motor 61 for driving the second driving gear 60 to rotate.

[0021] The first end of the transmission chain 30 is meshed with the main transmission sprocket 20, and the second end is meshed with a driven sprocket, which is arranged on the hub of the rear wheel of an electric motorcycle.

[0022] The first driving gear 40 , the intermediate gear 50 , the second driving gear 60 , the first driving motor 41 and the second driving motor 61 are all located at a side of the reduction gear 10 away from the driven sprocket.

[0023] The overrunning clutch 51 is an important component used for power transmission and separation between the prime mover and the working machine or between the driving shaft and the driven shaft inside the machine. It uses the speed change or rotation direction change of the driving and driven parts to perform self-clutching.

[0024] The first drive motor 41 is provided with a first encoder 42 , which can detect operating parameters of the first drive motor 41 , such as rotation speed, current, voltage, temperature or acceleration. The first drive motor 41 and the first encoder 42 are both connected to a first controller.

[0025] The second drive motor 61 is provided with a second encoder 62 , which can detect operating parameters of the second drive motor 61 , such as rotation speed, current, voltage, temperature or acceleration. The second drive motor 61 and the second encoder 62 are both connected to a second controller.

[0026] In one embodiment, a whole machine controller is further provided, and the whole machine controller communicates with both the first controller and the second controller to implement the instructions and coordinated work of the first drive motor 41 and the second drive motor 61 .

[0027] In another embodiment, the second controller is used as the master controller and the first controller is used as the slave controller. The master controller communicates with the slave controller to achieve coordinated operation of the first drive motor 41 and the second drive motor 61. Alternatively, the first controller is used as the master controller and the second controller is used as the slave controller.

[0028] In this embodiment, a brake 70 is further provided on the side of the reduction gear 10 facing away from the main drive sprocket 20 , and the brake 70 is used to decelerate and perform parking brake on the reduction gear 10 .

[0029] The second driving motor 61 and the second encoder 62 can be arranged flexibly, for example, they can be located on the side of the second driving gear 60 facing the first driving motor 41 , or on the side away from the first driving motor 41 .

[0030] In this embodiment, it also includes a shell 80, which is in the shape of a water droplet, with a large end and a small end, and the large end faces the driven sprocket, which can effectively reduce wind resistance. The output gear 10, the driving sprocket 20 and the brake 70 are all located in the large end, and an opening is provided on the side of the large end facing the driven sprocket, and the transmission chain 30 passes through the opening. The second drive gear 60, the second drive motor 61 and the second encoder 62 are all located in the small end, and the first drive gear 40, the first drive motor 41, the first encoder 42, the intermediate gear 50 and the overrunning clutch 51 are all located between the large end and the small end. The material of the shell 80 is aluminum alloy, and the external natural wind can be used to dissipate heat for the electric motorcycle dual-motor drive device provided by the present invention.

[0031] The first controller, the second controller or the whole machine controller also reads the operating current of the first drive motor 41 or the second drive motor 61 , and calculates the output torque according to the operating current of the first drive motor 41 or the second drive motor 61 .

[0032] The reduction ratio of the reduction gear 10 to the first drive gear 40 is 1:3 to 1:5, and the first drive gear 40 and the intermediate gear 50 have the same rotation speed; the reduction ratio of the intermediate gear 50 to the second drive gear 60 is less than 1:1 and greater than 1:2. Preferably, the reduction ratio of the reduction gear 10 to the first drive gear 40 is 1:4.4, and the reduction ratio of the intermediate gear 50 to the second drive gear 60 is 1:1.33. The reduction ratio of the reduction gear 10 to the first drive gear 40 can be set according to the result of the maximum vehicle speed calculation, and the reduction ratio of the intermediate gear 50 to the second drive gear 60 is set according to the result of the maximum output torque calculation.

[0033] The maximum rotation speed of the first driving motor 41 and the second driving motor 61 are both 6000 r / min.

[0034] When the rotation speed of the first drive motor 41 reaches 6000 r / min, the overrunning clutch 51 automatically separates the intermediate gear 50 from the first drive gear 40 to prevent the second drive motor 61 from overspeeding, thereby protecting the second drive motor 61 .

[0035] The present invention also provides a dual-motor driving strategy for an electric motorcycle, which operates with different deceleration combinations according to different speeds and riding conditions, and specifically includes the following steps:

[0036] Step S1: When the speed of the electric motorcycle is greater than 0 km / h and less than 50 km / h, the second controller controls the second drive motor 61 to work, and the first controller controls the first drive motor 41 to idle. The speed of the electric motorcycle can be calculated by the rotation speed detected by the first encoder 42.

[0037] Step S2: When the running speed of the electric motorcycle is greater than or equal to 50 km / h and less than 120 km / h, and the output torque is less than the predetermined torque value and the operating current of the second drive motor 61 is less than the predetermined current value, the second controller controls the second drive motor 61 to maintain operation, and the first controller controls the first drive motor 41 to idle.

[0038] Step S3: When the running speed of the electric motorcycle is greater than or equal to 50 km / h and less than 120 km / h, and the output torque is greater than or equal to the predetermined torque value or the working current of the second drive motor 61 is greater than or equal to the predetermined current value, such as climbing a 30% slope or accelerating for overtaking, the second controller controls the second drive motor 61 to work, and the first controller controls the first drive motor 41 to work, so that the first drive motor 41 and the second drive motor 61 are driven at the same time to increase the output torque. In this way, it is ensured that the total output torque of the motor meets the vehicle demand and the second drive motor 61 is not overloaded.

[0039] Step S4: When the running speed of the electric motorcycle is greater than or equal to 120 km / h, the first controller controls the first drive motor 41 to work, the second controller controls the second drive motor 61 to stop working, and controls the overrunning clutch 51 to disconnect the power transmission between the intermediate gear 50 and the first drive gear 40. In this way, the second drive motor 61 is protected from overspeed.

[0040] Step S5: When one of the first controller or the second controller fails, the corresponding first drive motor or the second drive motor will idle and will not produce resistance to the power transmission; at the same time, the other controller enters the working state and works under control within the predetermined current value range to send the rider to the destination.

[0041] This allows the bike to operate at a higher efficiency in each riding phase, preventing the motor from running in an inefficient range and wasting precious battery power.

[0042] The second controller can read the working current of the second drive motor 61. When the working current of the second drive motor 61 is greater than the predetermined current value, the first controller controls the first drive motor 41 to work for a predetermined time. When the electric motorcycle dual-motor drive device provided by the present invention climbs a slope or accelerates, the current increases rapidly, generating a total peak current. At this time, the first drive motor 41 and the second drive motor 61 work at the same time near the peak current to overcome the short peak working condition. In this way, a high-power motor can be replaced by a low-power motor to reduce costs.

[0043] Furthermore, the first drive motor 41 has the function of generating electricity. When the intermediate gear 50 drives the first drive motor 41 to rotate passively, it can reversely charge the battery pack of the entire vehicle through the first controller. Since the first drive motor 41 has a copper wire stator and a permanent magnet rotor, the copper wire can drive the permanent magnet rotor to rotate relative to the stator after the first drive motor 41 is powered on; when the permanent magnet rotor of the first drive motor 41 passively rotates relative to the stator, the permanent magnet magnetic field will cut the magnetic lines of force of the copper wire, so that current is generated in the copper coil of the stator, and the battery pack of the entire vehicle is reversely charged. The first drive motor 41 is used for power generation in the following situations: 1. During braking, the speed of the first drive motor 41 and the second drive motor 61 is opposite to the torque, and the first drive gear 40 continues to rotate due to inertia, thereby driving the first drive motor 41 to generate electricity; 2. During downhill driving, the speed of the first drive motor 41 and the second drive motor 61 is opposite to the torque, and the first drive gear 40 continues to rotate due to inertia, thereby driving the first drive motor 41 to generate electricity; 3. When the running speed of the electric motorcycle is greater than 0 km / h and less than 50 km / h, and when the running speed of the electric motorcycle is greater than or equal to 50 km / h and less than 120 km / h and the output torque is less than the predetermined torque value, the second drive motor 61 works, the first drive motor 41 is dragged by the intermediate gear 50, and the first drive motor 41 generates electricity. In this way, energy can be recovered with maximum efficiency.

[0044] Since the first drive motor 41 and the second drive motor 61 are controlled by the first controller and the second controller respectively, if one of the controllers fails, the electric motorcycle dual-motor drive device provided by the present invention can still be controlled by the other controller, so that the electric motorcycle can still run without breaking down.

[0045] The electric motorcycle dual-motor driving device provided by the present invention does not require a gear shifting mechanism, effectively reduces costs, and has no sense of frustration.

[0046] The electric motorcycle dual-motor drive device provided by the present invention can reduce the power of each drive motor by arranging two drive motors, and can avoid using a water-cooling heat dissipation mechanism as much as possible, such as using wind speed heat dissipation in a natural environment, thereby reducing costs.

[0047] Compared with the prior art, the electric motorcycle dual-motor drive device of the present invention comprises a reduction gear 10, a main transmission sprocket 20 coaxially arranged with the reduction gear 10, a transmission chain 30 matched with the main transmission sprocket 20, a first drive gear 40 meshing with the reduction gear 10, an intermediate gear 50 coaxially arranged with the first drive gear 40, a second drive gear 60 meshing with the intermediate gear 50, an overrunning clutch 51 for realizing power transmission or separation between the intermediate gear 50 and the first drive gear 40, a first drive motor 41 for driving the first drive gear 40 to rotate, and a second drive motor 61 for driving the second drive gear 60 to rotate; the first end of the transmission chain 30 is meshed with the main transmission sprocket 20, and the second end is meshed with a driven sprocket. In this way, the motor has different reduction combinations under different riding conditions, so that the motor has high efficiency in each stage, automatic operation, no sense of frustration, wide speed coverage, taking into account acceleration and climbing, increasing the cruising range and having redundant protection functions. The present invention also provides a dual-motor drive strategy for electric motorcycles. The present invention also provides a dual-motor drive strategy for electric motorcycles.

[0048] The above are only preferred embodiments of the present invention and are not intended to limit the protection scope of the present invention. Any modification, equivalent substitution or improvement within the spirit of the present invention is included in the scope of the claims of the present invention.

Claims

1. A dual-motor drive device for an electric motorcycle, characterized in that: The electric motorcycle comprises a reduction gear, a main transmission sprocket coaxially arranged with the reduction gear, a transmission chain matched with the main transmission sprocket, a first driving gear meshed with the reduction gear, an intermediate gear coaxially arranged with the first driving gear, a second driving gear meshed with the intermediate gear, an overrunning clutch for realizing power transmission or separation between the intermediate gear and the first driving gear, a first driving motor for driving the first driving gear to rotate, and a second driving motor for driving the second driving gear to rotate; a first end of the transmission chain meshes with the main transmission sprocket, and a second end meshes with a driven sprocket fixed to the rear wheel of the electric motorcycle; the first driving gear, the intermediate gear, the second driving gear meshed with the first driving gear, The driven gear, the first drive motor and the second drive motor are all located on the side of the reduction gear away from the driven sprocket. The first drive motor is provided with a first encoder, and the first drive motor and the first encoder are both connected to a first controller. The second drive motor is provided with a second encoder, and the second drive motor and the second encoder are both connected to a second controller. The maximum speed of the first drive motor and the second drive motor is 6000r / min. When the speed of the first drive motor reaches 6000r / min, the overrunning clutch automatically separates the intermediate gear from the first drive gear. When working, when the walking speed of the electric motorcycle is greater than 0km / h and less than 50km / h, the second controller controls the second drive motor to work, and the first controller controls the first drive motor to idle; when the running speed of the electric motorcycle is greater than or equal to 50km / h and less than 120km / h, and the output torque is less than the predetermined torque value, and the working current of the second drive motor is less than the predetermined current value, the second controller controls the second drive motor to keep working, and the first controller controls the first drive motor to idle; when the running speed of the electric motorcycle is greater than or equal to 50km / h and less than 120km / h, and the output torque is greater than or equal to the predetermined torque value or the working current of the second drive motor is greater than or equal to the predetermined current value When the current value is constant, the second controller controls the second drive motor to maintain operation, and the first controller controls the first drive motor to participate in the operation; when the running speed of the electric motorcycle is greater than or equal to 120km / h, the first controller controls the first drive motor to work, and the second controller controls the second drive motor not to work, and at the same time controls the overrunning clutch to disconnect the power transmission between the intermediate gear and the first drive gear; when one of the first controller or the second controller fails, the corresponding first drive motor or the second drive motor is controlled to idle, and no resistance is generated to the power transmission; at the same time, the other controller enters the working state and works within the predetermined current range.

2. The electric motorcycle dual-motor driving device according to claim 1, characterized in that: The device also has a whole machine controller, which communicates with both the first controller and the second controller.

3. The dual-motor driving device for an electric motorcycle as claimed in claim 2, characterized in that: The first controller, the second controller or the whole machine controller reads the operating current of the first drive motor or the second drive motor and calculates the output torque according to the operating current.

4. The electric motorcycle dual-motor driving device according to claim 1, characterized in that: The second controller serves as a master controller and the first controller serves as a slave controller; or the first controller serves as a master controller and the second controller serves as a slave controller; the master controller is connected or communicates with the slave controller.

5. The electric motorcycle dual-motor driving device according to claim 1, characterized in that: A brake is arranged on the side of the reduction gear facing away from the main transmission sprocket.

6. The electric motorcycle dual-motor driving device according to claim 1, characterized in that: The first drive motor, the second drive motor, the reduction gear, the first drive gear, the intermediate gear and the second drive gear are all arranged between the front wheel and the rear wheel of the electric motorcycle and fixed on the straddle frame of the electric motorcycle. The main drive sprocket is connected to the driven sprocket through a transmission chain.

7. The dual-motor driving device for an electric motorcycle as claimed in claim 1, characterized in that: The reduction ratio between the reduction gear and the first driving gear is 1:3 to 1:5, and the rotation speed of the first driving gear is the same as that of the intermediate gear; the reduction ratio between the intermediate gear and the second driving gear is less than 1:1 and greater than 1:2.

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