WO2004016459A1

WO2004016459A1 - Electric-vehicle power and driving device

Info

Publication number: WO2004016459A1
Application number: PCT/CN2003/000686
Authority: WO
Inventors: Yaoqing Yu; Bin Yu; Naiming Chen
Original assignee: Yaoqing Yu; Bin Yu; Naiming Chen
Priority date: 2002-08-16
Filing date: 2003-08-18
Publication date: 2004-02-26
Also published as: AU2003257796A1

Abstract

The present invention relates to an electric-vehicle power and driving device, which comprises at least two drive wheels (4), wherein the power device of the electric-vehicle uses at least two drive motors (1) to drive the two wheels (4) respectively. The present invention omits the clutch, the transmission, the differential gear and so on, which reduces the weight of the whole electric-vehicle and improves the transmission efficiency, as well as keeps the stability of the straight running and the reliability of the steering performance of the electric-vehicle.

Description

TECHNICAL FIELD

The present invention relates to the arrangement or installation of an electric power device and a vehicle transmission device of more than one motor, in particular to a power and transmission device of an electric vehicle. Background technique

The importance of electric vehicles as the green and environmentally-friendly transportation of the future goes without saying. At present, the main obstacle that restricts the entry of electric vehicles into commercial operation is the energy structure. For pure electric vehicles, the specific energy of existing batteries is very low. Taking lithium-ion batteries with high energy storage efficiency as an example, the specific energy is

120-140W. H / kg, while the energy per kilogram of gasoline is 12400-1 3500W. 21H / kg, a difference of 100 times. For users, they will never use a vehicle with very poor power performance specifically to protect the environment. This is also an important reason why pure electric vehicles are difficult to enter into commercial operation, and it has become a world of long-term defeat. Puzzle.

At present, the development of electric vehicles basically follows the structural model of traditional internal combustion engine vehicles.

Drive motor-clutch-gearbox-rear axle-differential-wheel

The biggest shortcomings of this traditional transmission mode are: (1) the traditional chain is very long and the transmission efficiency is low; (2) the transmission device occupies valuable space, especially increases the weight of the entire vehicle and increases the requirements Driving power. With the development of mechatronics and control technology, there have also been some new advances in electric vehicle transmission technology. For example, the scheme of driving a differential device directly by a motor through a reducer to drive the walking wheels; The differential device can output at both ends, drive the traveling wheels, and so on. These ^: methods are indeed effective in improving transmission efficiency and improving vehicle weight reduction, but they are not enough to solve the main problems in electric vehicle transmission.

A company in China has also conducted an experiment on installing two hub motors on two rear wheels in an electric vehicle. Due to the weight of the low-speed motor, it was directly installed in the wheel, which caused the weight under the suspension to increase too much, affecting It improves the comfort and smoothness of the vehicle. Summary of the invention

An object of the present invention is to provide a power and transmission device for an electric vehicle. The power device and the transmission device are improved to further improve the transmission efficiency of the electric vehicle and achieve a major breakthrough in the weight reduction of the entire vehicle. Provides important conditions for commercialization of electric vehicles.

The technical solution adopted by the present invention to solve its technical problems is: a power and transmission device of an electric vehicle, which includes at least two driving wheels, wherein the power device driving the electric vehicle is at least two speed-regulating driving motors, which respectively drive the said Two driving wheels.

The two driving wheels in the present invention may be a front wheel drive for two front wheels, or a rear wheel drive for two rear wheels.

The two driving motors for front-wheel drive according to the present invention can be installed in a front power compartment, and are mounted on a special longitudinal beam on the vehicle body through a motor mounting bracket and a damping device.

As another way, the ¾ drive motors for rear-wheel drive according to the present invention can be installed in the rear power, and are mounted on a dedicated side member on the vehicle body through a motor mounting bracket and a damping device.

As an alternative embodiment of the present invention, there may be four driving wheels, of which two front driving wheels are driven by two driving motors respectively; two rear driving wheels may be driven by one or two driving motors.

The above two front drive motors can be placed in the front power compartment, and one or two rear drive motors can be placed in the rear power compartment. The mounting brackets with shock absorption devices are fixed to the longitudinal beams on both sides of the front and rear power compartments. on.

The driving motor in the present invention can be connected to the driving wheels through a speed reducer and a transmission shaft, respectively, so as to transmit power.

When there is one rear drive motor in the present invention, the rear drive motor is connected to a reducer. The reducer is provided with a bidirectional output shaft, and an upper ball cage is provided on the output shaft on each side. The lower ball cage provided on the rear drive wheel is connected, and an overrunning clutch in the opposite direction is installed between the reducer and the upper ball cage.

When there are two rear drive motors of the present invention, each one is connected to a reducer, each The reducer is provided with an output shaft, and each output shaft is provided with an upper ball cage, and is connected to the lower ball cage provided on the rear driving wheel through a transmission shaft, and the output shaft is connected between the reducer and the upper ball cage. Each is equipped with an overrunning clutch in the opposite direction.

The control mode of the driving motor of the present invention can adopt constant torque control to ensure the differential speed during synchronous operation and steering. Further, when the driving motor is in a starting state, a constant speed control may be adopted to increase the starting torque.

In this way, the drive motor fixed in the front or rear power compartment can directly transmit power to the drive wheels through the transmission shaft. If the motor used is a high-speed motor, a reducer needs to be added so that the speed of the driving motor can match the speed of the traveling wheel. This structural mode change has also changed in function. The stepless speed regulation of the motor is used instead of the gearbox: the two motors are driven separately to replace the differential mechanism; the direct drive is used to replace the multi-stage drive.

When the present invention adopts front-wheel drive, its working principle is as follows: two motors with constant torque control drive two front wheels respectively, and when the accelerator controlling the speed of the motor is at a certain position,

The torques of the two motors M _ER = M _B1 = 1 / 2M _E. When the torque M _E is equal to the drag torque, the electric vehicle keeps running at a constant speed. When accelerating, when the accelerator pedal is depressed, the input current of the motor increases, the torque M _E increases accordingly, and the electric vehicle accelerates. Otherwise it slows down. When steering, the drag torque of the inner wheels increases, the speed of the inner wheels decreases, the drag torque of the outer wheels decreases, and the speed increases. The electric vehicle will smoothly change the direction of travel as the wheels deflect.

When the present invention adopts rear-wheel drive, two motors with constant torque control drive the two rear wheels respectively. When the accelerator that controls the speed of the motor is at a certain position, I _R = ^ the torque of the two motors

When the torque and the reluctance torque is equal to M _E, an electric vehicle to maintain constant speed operation. When accelerating, when the accelerator pedal is depressed, the input current of the motor increases, the torque M _E increases accordingly, and the electric vehicle accelerates. Otherwise it slows down. The front wheels can be similar to existing rear-wheel-drive cars, and are provided with a directional control mechanism for controlling the running direction of the electric vehicle.

When the present invention uses four driving wheels, that is, both the front and rear wheels can be driving wheels, the working principle is as follows: (1) Only the front driving motor works when running at normal speed. Both drive motors are speed-regulating motors with constant torque control. When the throttle (accelerator) is in a certain position, the The current is equal to I _FR = I _F L, and the torque and torque of the left and right motors are also equal. M _EFR = M _EFI = 1 / 2M _EF , the electric vehicle runs in 4 x 2 mode. The car runs at a constant speed. When the road is downhill, the drag torque is reduced, the torque is greater than the drag torque, and the vehicle speed is automatically increased. Conversely, when the electric vehicle is on an uphill state, the vehicle speed is automatically reduced. When you need to accelerate, increase the throttle and step on the accelerator, the input current of the motor increases, the torque M _EF increases accordingly, and the electric vehicle accelerates. Otherwise it slows down. When steering, as the steering wheel rotates, the two front wheels deflect accordingly, the drag torque of the inner wheels increases, and its speed decreases accordingly, while the increase of the drag torque of the outer wheels is small, and the decrease of the speed is also small. Small, the electric vehicle will smoothly change its running direction as the steering wheel rotates and the front wheels deflect.

When the electric vehicle is in the 4x2 running mode, the speed of the rear drive motor is 0, and the speed of the rear wheel is close to that of the front wheel with the movement of the vehicle. Because the overrunning clutch is installed on the output shaft of the drive motor, when the speed of the rear wheel is greater than When the motor is driven, the drive chain is cut off, and the motor does not rotate with subsequent wheels.

(2) When the driving force of the front wheels is not sufficient to meet the needs of the electric vehicle, such as starting on a hill, high-speed operation, and when it is necessary to improve acceleration, it is necessary to start the rear-wheel drive motor. The starting of the rear drive motor is performed by the following methods. A controller is set on the power supply line of the front wheel, and the current of the current drive motor is greater than the set value I. When I _F > I. When the circuit of the rear wheel drive motor is closed, the rear drive motor starts to work, and the electric vehicle works in 4 X 4 mode. The torque changes from M _EF to M _E , the torque increases, and the power of the electric vehicle is improved. Slope starting performance and top speed will also increase. When the electric vehicle is steering in the 4 X 4 drive mode, the front wheels deflect to the side with the steering wheel, the speed of the inner motor decreases due to the increase of the inner wheel resistance torque, and the increase of the outer wheel motor due to the outer wheel resistance torque is small. , The speed of the outer motor decreases less, and the whole vehicle will smoothly turn to the deflection side. When there is one rear drive motor, the rear drive motor reducer has two left and right output shafts, each of which is connected to a constant speed directional joint after passing an overrunning clutch. When the electric vehicle is in a steering state, the speed of the inner wheel decreases, The rear drive motor will drive the inner wheels for synchronous operation. The speed of the outer wheels should be higher than the speed of the reducer. The overrunning clutch is in the cut-off state. The outer wheels become free wheels, which will not affect the steering of the vehicle. When there are two rear drive motors, because the constant torque control mode is used, the left and right motors will automatically adjust the speed according to the resistance torque of the walking wheels on both sides (the situation is similar to the front wheel) . Regarding the coordination between the front and rear wheels, the constant torque control mode is adopted. There is no interference between the rear wheels.

The beneficial effects of the present invention are: (1) The transmission efficiency is high. Compared with the traditional power transmission, this mode of two motors driving two front wheels or two rear wheels, respectively, simplifies power transmission, which can improve transmission efficiency and reduce energy consumption by 4%; (2) Promote vehicles Lightweight. The power transmission mechanism is simplified, and the direct effect is to greatly reduce the weight of the entire vehicle. For electric vehicles, the weight of the vehicle body can reduce d, the energy consumption of the vehicle drive, and the weight of the vehicle body can be increased. The large battery capacity increases the running mileage after a single charge; (3) The manufacturing difficulty is reduced, and P reduces the production cost. The manufacturing accuracy and complexity of internal combustion engines is much higher than that of motors and their control systems. Therefore, under the condition of mass production, the production cost of the power transmission device will be greatly reduced. (4) The maintenance workload is reduced, and maintenance costs are reduced. Compared with the internal combustion engine, the electric motor can be considered as a non-faulty or less faulty product, and the workload of its use and maintenance is very small, and the corresponding maintenance costs will also decrease.

In addition, since the present invention can also adopt four driving wheels, it not only maintains the beneficial effects of the dual-machine front-wheel drive 4X2 operation mode described above, but also increases the power of the entire vehicle, improves the power of the electric vehicle, and accelerates Performance and starting performance have been significantly improved; the economy of normal operating speed has been further improved, and energy consumption has been reduced. BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 Schematic diagram of dual-motor front-drive 4X2 drive mode;

Figure 2 Schematic diagram of three drive motors as a power pack;.

Figure 3 Schematic diagram of four drive motors as a power pack.

Figure number description:

1 drive motor; 2—reducer; 3—drive shaft; 4—drive wheel; 5—vibration pads; 6—mounting frame; 7—longitudinal beam; 8—upper ball cage; 9—lower ball cage; 10—beyond clutch. detailed description

As shown in FIG. 1-3, the power and transmission device of an electric vehicle according to the present invention includes at least two driving wheels 4, wherein the power device driving the electric vehicle is at least two speed-regulating driving motors 1, respectively. Moving the two driving wheels 4. The two driving wheels may be a front wheel driving method with two front wheels as shown in FIG. 1, or a rear wheel driving method with two rear wheels (not shown in the figure).

Because the present invention eliminates many components of conventional automobiles such as clutches, transmissions, and differentials, it reduces the weight of the entire vehicle, improves transmission efficiency, maintains the smoothness of linear operation of electric vehicles, and reliable steering performance.

The driving motor 1 in the present invention may be specifically installed in a power compartment, and is mounted on a special longitudinal beam 7 on a vehicle body through a motor mounting frame 6 and a shock absorbing device 5.

As shown in FIG. 2 and FIG. 3, the number of the driving wheels 4 may be four, in which two front driving wheels 4 are driven by two driving motors 4 respectively; two rear driving wheels 4 may be driven by one or two driving wheels 4. Motor 1 is driven. In this way, the power of the entire vehicle can be increased, the power of the electric vehicle can be improved, and the acceleration and starting performance are significantly improved; the economy of the normal operating speed is further improved, and the energy consumption is reduced.

The following further describes the present invention through specific examples: Embodiment 1

As shown in FIG. 1, in this embodiment, a four-wheel electric car is taken as an example to describe in detail the case of front-wheel drive of the present invention. The body of the car is made of composite materials, with a curb weight of 1027kg. In the front power compartment, two longitudinal beams 7 are connected to the left and right inner leaf plates, and the rear is connected to the dash panel. It is the main load-bearing structure of the vehicle body. 6 is the motor mounting frame. Pad) is connected to the longitudinal beam 7 of the vehicle body, and two driving motors 1 are installed below the mounting frame 6, the driving motor 1 can be a high-speed motor n = 8000r / m, and the output end of the motor can be installed with a 8: 1 planetary reducer 2. An output ball 21 of the speed reducer 2 is provided with an upper ball cage 8 of a constant velocity direction joint, and is connected to another lower ball cage 9 inside the driving wheel 4 through a transmission shaft 3. Since the drive motor 1 is fixed to the vehicle body, the weight under the suspension does not increase, and the comfort during operation is not affected. The straight-line running and steering performance is also good. When the unilateral walking wheel is on the soft ground, the passability is higher than the traditional mechanical differential device. When the accelerator of the motor speed is at a certain position, I _R =: ^ the torque of the two motors M _ER = M _EI = 1 / 2M _E , When the torque and the reluctance torque is equal to M _E, an electric vehicle running speed holding hook. When accelerating, when the accelerator pedal is depressed, the input current of the driving motor 1 increases, the torque M _E increases accordingly, and the electric vehicle accelerates. Otherwise it slows down. When steering, the drag torque of the inner wheels increases, the speed of the inner wheels decreases, the drag torque of the outer wheels decreases, and the speed increases. The electric vehicle will smoothly change the direction of travel as the wheels deflect.

In this way, the drive motor 1 fixed in the front power compartment can directly transmit power to the drive wheels 4 through the transmission shaft 3. If the driving motor 1 used in this embodiment is a high-speed motor, a speed reducer 2 needs to be added so that the rotation speed of the driving motor 1 can match the rotation speed required for the driving wheels 4. This structural mode change also changes its function. The stepless speed regulation of the drive motor is used instead of the gearbox: the two motors are driven separately to replace the differential mechanism; the direct drive is used to replace the multi-stage drive. As a result, the weight of the entire vehicle is greatly reduced, the transmission efficiency is improved, and the straight-line running stability and reliable steering performance of the electric vehicle are maintained. Example 2

As shown in FIG. 2, in this embodiment, three driving motors 1 and four driving wheels 4 are provided, and two front driving wheels 4 thereof are driven by two front driving motors 1 respectively. The two driving motors 1 are fixed to the left and right side members 7 of the front compartment through a mounting bracket 6 with a damping device. The output ends of the driving motors 1 are connected to the reducer 2. The output shaft 21 of the reducer 2 is mounted on the output shaft 21 and the like. The upper ball cage 8 of the speed direction joint is connected with the lower ball cage 9 fixed on the front drive wheel 4 through the transmission shaft 3. As shown in FIG. 2, there is only one rear drive motor 1. Like the front drive motor 1, the rear drive motor 1 is also fixed to the rear left and right side members 7 (not shown in the figure) through a mounting bracket 6 with a damping device 5. The drive motor 1 is connected to the reducer 2. The output shaft 21 of the reducer 2 is bidirectional. Each side is equipped with an overrunning clutch 10 in the opposite direction, and is connected to the upper ball cage 8 of the constant velocity universal joint. It is connected to the lower ball cage 9 fixed inside the rear wheel.

The working principle is as follows: (1) In normal speed operation, only the front drive motor works. The working process is the same as that in the first embodiment in which only the front-wheel drive is adopted, and details are not described herein again. At this time, the electric vehicle is in the 4x2 running mode, the rotation speed of the rear drive motor 1 is 0, and the speed of the rear wheels is close to that of the front drive wheels 4 due to the movement of the entire vehicle. Since the overrunning clutch 10 is installed on the output shaft of the drive motor 1 When the rotation speed of the rear driving wheel 4 is greater than the driving motor 1, the transmission chain is cut off and the driving motor 1 The driving wheel 4 is not rotated afterwards.

(2) When the driving force of the current driving wheels 4 is insufficient to meet the requirements of the electric vehicle, such as starting on a hill, running at high speed, and when acceleration is required, the rear wheel driving motor 1 needs to be started. The starting of the rear drive motor 1 is performed in the following manner. A controller is provided on the power supply line of the front drive wheels 4, and the current I _{F of the} current drive motor 1 is greater than the set value I. When I _F > I _Q , the circuit of the rear wheel drive motor 1 is closed, the rear drive motor 1 starts to work, and the electric vehicle works in a 4 x 4 mode. The torque changes from M _EF to M _E , and the torque increases. , The power of the electric vehicle will be improved, and the starting performance on the slope and the maximum speed will also be improved. When the electric vehicle is steering in the 4 x 4 drive mode, the front drive wheels 4 deflect to the side with the steering wheel, the speed of the inner drive motor 1 decreases due to the increase of the inner wheel resistance torque, and the outer wheel drive motor 1 decreases due to the outer wheels. The added value of the drag torque is small, the rotation speed of the outer drive motor 1 is reduced less, and the entire vehicle will smoothly steer to the deflection side. When the electric vehicle is in a steering state, the speed of the inner wheels decreases. The rear drive motor 1 will drive the inner wheels for synchronous operation. The speed of the outer wheels is higher than the speed of the reducer 2. The overrunning clutch 10 is in the off state, and the outer wheels become Free wheels will not affect the steering of the vehicle.

In this way, by adding rear-wheel drive on the basis of front-wheel drive, the power of the entire vehicle is increased, the power of the electric vehicle is improved, and the acceleration and starting performance are significantly improved; the normal operation is further improved. The economy of speed reduces energy consumption. Example 3

As shown in FIG. 3, the basic structure, working principle, and process of this embodiment are the same as those of Embodiment 2, and details are not described herein again.

The difference between this embodiment and Embodiment 2 is that, as shown in FIG. 3, in this embodiment. There are two rear drive motors 1 each connected to a reducer 2. Each reducer 2 is provided with an output shaft 21, and each output shaft 21 is provided with an upper ball cage 8 and passes through a transmission shaft. 3 is connected to the lower ball cage 9 fixedly mounted on the rear drive wheel 4, and an overrunning clutch 10 with an opposite direction is installed between the speed reducer 2 and the upper ball cage 8. The two drive motors 1 use a constant torque control mode. The left and right drive motors 1 will automatically adjust the speed according to the resistance torque of the drive wheels on both sides. Case of the front wheel in Example 1). Regarding the coordination between the front and rear wheels, since the constant torque control mode is adopted, no interference is formed between the front and rear traveling wheels.

Since the basic structure, working principle, and process of this embodiment are the same as those of Embodiment 2, it also has the beneficial effects described in Embodiment 2, which will not be described in detail here.

The above specific embodiment examples are only used to illustrate the present invention, but not intended to limit the present invention. The situation of the rear-wheel drive of the present invention is basically similar to that of the first embodiment. And it can be used not only in four-wheel electric vehicles, but also in three-wheel electric vehicles driven by rear wheels. The speed regulating driving motor in the present invention may be a DC speed regulating motor or an AC speed regulating motor, which is not limited here.

Claims

Claim

1. A power and transmission device for an electric vehicle, comprising at least two driving wheels, characterized in that the power device for driving the electric vehicle is at least two speed-regulating driving motors, which respectively drive the two driving wheels.

2. The power and transmission device for an electric vehicle according to claim 1, wherein the two driving wheels are two front wheels constituting front wheel drive, or two rear wheels constituting rear wheel drive.

3. The power and transmission device for an electric vehicle according to claim 2, characterized in that both drive motors for front-wheel drive are provided in the front power compartment, and are mounted on the motor mounting bracket and shock absorbing device in On the side rails dedicated to the body.

4. The power and transmission device of an electric vehicle according to claim 2, characterized in that both driving motors for rear wheel driving are arranged in the rear power compartment, and are mounted on the motor mounting bracket and the shock absorption device On the side rails dedicated to the body.

5. The power and transmission device of an electric vehicle according to claim 1, wherein the number of said driving wheels is four, wherein two front driving wheels are driven by two driving motors respectively; two rear driving wheels Can be driven by one or two drive motors.

6. The power and transmission device of an electric vehicle according to claim 4, wherein two front drive motors are placed in the front power compartment, and one or two rear drive motors are placed in the rear power compartment. The mounting bracket of the shock absorbing device is fixed on the longitudinal beams on both sides of the front and rear power compartments.

7. The power and transmission device for an electric vehicle according to any one of the preceding claims, wherein the driving motor is connected to the driving wheels through a speed reducer and a transmission shaft, respectively, and thereby transmits power.

8. The power and transmission device for an electric vehicle according to claim 4, wherein the rear drive motor is one connected to a reducer, and the reducer is provided with a bidirectional output shaft, and An upper ball cage is provided on one side of the output shaft, and is connected to a lower ball cage provided on the rear driving wheel through a transmission shaft, and an overrunning clutch in the opposite direction is installed between the reducer and the upper ball cage.

9. The power and transmission device of an electric vehicle according to claim 4, characterized in that there are two rear drive motors, each of which is respectively connected to a reducer, and each of the reducers is provided with a The output shaft is provided with an upper ball cage on each output shaft, and is connected to a lower ball cage fixed on the rear driving wheel through a transmission shaft, and is installed on the output shaft between the reducer and the upper ball cage. Equipped with overrunning clutch in opposite direction.

10. The power and transmission device for an electric vehicle according to claim 1, wherein the control mode of the driving motor adopts constant torque control to ensure the differential speed during synchronous operation and steering.

11. The power and transmission device of an electric vehicle according to claim 1 or 10, characterized in that, when the driving motor is in a starting state, constant speed control can be adopted to increase the starting torque.