CN108394271A - A kind of distributed three motors driving power system - Google Patents

Abstract

The invention belongs to the technical field of drive systems for pure electric vehicles, and in particular relates to a distributed three-motor drive pure electric power system, which mainly includes a first motor, a second motor, a third motor, a differential, a final reducer, and an inverter. device, battery pack, fixed speed ratio reducer, high-voltage cabinet, charger, vehicle controller including battery management system, electronic control controller, etc.; the advantages of the present invention are: 1. Through distributed drive, the single motor The driving form is changed to a small power motor on the front axle and motors with the same power on the two wheels of the rear axle. Under the premise of ensuring the overall dynamic performance of the vehicle remains unchanged, the vehicle can not only work in the two-wheel drive mode, but also realize Timely four-wheel drive can adapt to various working conditions; 2. According to the driving needs of the vehicle, different modes can be switched. When the demand is small, it is driven by a single-axis motor, and when the demand is large, it is driven by three motors on the front and rear axles. Under the same vehicle load conditions, The load rate of a single motor is improved, the working efficiency of the motor is obviously improved, the power consumption is reduced, and the economy of the vehicle is greatly improved.

Description

A distributed three-motor drive power system

technical field

The invention relates to the technical field of a pure electric vehicle drive system, in particular to a pure electric vehicle power system.

Background technique

With the increasingly serious environmental problems and the oil crisis, countries have introduced policies and regulations. On the one hand, traditional vehicles fueled by oil and gasoline have been restricted and impacted. It is required to become a research hotspot in universities, scientific research institutions and large car companies in various countries. As the most promising and important branch of new energy vehicles, electric vehicles have renewable energy and are completely non-polluting, so they have been set as the ultimate strategic goal of the current transformation of the automobile industry in my country.

The pure electric vehicle is driven by a motor, and the integral drive system is driven by a motor. On the one hand, the larger load greatly increases the size and volume of the motor, which increases the difficulty of installation; The power required by the motor is different. Simple front-drive, rear-drive or four-wheel drive cannot maximize the use of the characteristics of the motor and reduce the efficiency of the motor.

Contents of the invention

In order to solve the shortcomings of the above-mentioned technologies, the present invention provides a distributed three-motor drive power system, which is easy to install, can better meet the power requirements of different driving conditions, and has strong adaptability; under the same vehicle load conditions, the working efficiency of a single motor Greatly improved, reduced power consumption, increased driving range, and improved motor efficiency.

For solving above-mentioned technical scheme, the present invention adopts following technical scheme:

A distributed three-motor drive pure electric power system, including a first motor, a second motor, a third motor, a differential, a final reducer, two fixed-ratio reducers, three inverters, a high-voltage cabinet, Charger, battery pack, vehicle controller, and external charging connector; the output power of the first motor output drives the front axle of the vehicle through the final reducer and differential, and the power transmission route is mechanically connected; the second Both the motor and the third motor are wheel-side motors. The output shaft of the motor is decelerated and increased by a fixed speed ratio reducer to drive the rear axle of the vehicle. The power transmission route is mechanically connected; the external charging connector can be connected to an external power socket. The battery pack is charged through the charger and the high-voltage cabinet, and the charging line is electrically connected; the output end of the battery pack provides electric energy for the first motor, the second motor, and the third motor respectively through the high-voltage cabinet and the inverter. The connection is an electrical connection; the vehicle controller is connected to the battery pack including the battery management system, inverter, and high-voltage cabinet for signal connection to control the entire electric drive system.

Further, the first motor, the second motor, and the third motor respectively drive the front and rear axles, wherein the front axle has one wheel motor, and the rear axle has two wheel motors. The power of the wheel motors of the same shaft is the same, and the motors of the front and rear axles can be According to the requirements of the same design success rate or different power, the positions of the front and rear axle motors can be exchanged for the front axle dual motors and the rear axle single motor arrangement.

Further, the reducer on the output shaft of the wheel motor is selected according to the requirement and the number of gears is set, or the final reducer is not provided according to the requirement, and the vehicle is directly driven by the motor.

Further, the reducer is a fixed speed ratio reducer.

Further, the above system includes a single-motor drive mode, a dual-motor joint drive mode, a dual-axis three-motor joint drive mode, a braking energy recovery mode, and a parking charging mode: Among them, in the single-motor drive mode and the dual-motor joint drive mode, where One shaft motor drives the vehicle alone when the vehicle load is low, making full use of the characteristics of the motor, and ensuring that the motor has a high load rate and works in a high-efficiency range; When the vehicle load is high, the vehicle is jointly driven. At this time, the three motors have a high load rate and work in their respective high-efficiency ranges; in the braking energy recovery mode, when the vehicle controller detects a braking signal, the motors Part of the braking energy is recovered and converted into electric energy to charge the battery pack; in the parking charging mode, the vehicle is connected to an external charging plug and an external charging socket to charge the battery pack when the vehicle is parked.

Further, the braking energy recovery mode and the parking charging mode of the above system are not performed at the same time.

The working principle of the present invention is: when the vehicle load is low, one of the shaft motors of the system, the front axle or the rear axle, decelerates and increases the torque through the reducer to drive the vehicle independently, and the motor of the other shaft is turned off, which can not only meet the driving needs of the vehicle , it can also make the motor work in a relatively high-efficiency area, and realize the front or rear drive of the vehicle; when the vehicle load is high, such as climbing or accelerating, the single-axis motor drive work is difficult to meet the demand. At this time, three motors are driven by The respective transmission systems drive the vehicle together, and distribute the load to the three motors, so that the three motors have a higher load rate, so that they can work in their respective high-efficiency ranges, and the four-wheel drive mode of the vehicle can be realized; when the vehicle brakes , All three motors perform braking energy recovery, which improves the braking energy recovery rate and shortens the braking distance.

The advantage of the present invention is that: the present invention provides a distributed three-motor drive power system. The front and rear axles are respectively driven by the respective transmission systems of one motor on the front axle and two wheel side motors on the rear axle. According to the driving requirements of the vehicle, the vehicle can realize front Driven by a single motor on the axle, driven by dual motors on the rear axle, and driven by three motors on the front and rear axles. Compared with a single large motor driven separately, the working efficiency of a single motor is greatly improved under the same vehicle load conditions, reducing power consumption and increasing driving speed. mileage, improving the efficiency of the motor.

Different from the single-motor centralized driving vehicle of traditional pure electric vehicles, the system uses three relatively small-power motors to drive the front and rear axles of the vehicle respectively. The load rate of the motor is greatly improved, thereby improving the working efficiency of the motor and reducing power consumption; at the same time, the system can realize single-motor drive mode, dual-motor common drive mode, front and rear axle three-electric joint drive, which can better meet different driving conditions. Power requirements under working conditions; double-axis and three-motor braking energy recovery can recover more energy than single-axis, which is beneficial to shorten the braking distance.

Description of drawings

Fig. 1 is a schematic diagram of the overall structure of the distributed three-motor driven pure electric power system of the present invention.

Explanation of symbols in the figure:

1—differential; 2—half shaft; 3—front wheels; 4—final drive;

5—the first motor; 6, 11, 12—the first, second, and third inverters; 7—charger; 8—high voltage cabinet;

9—vehicle controller; 10—battery pack; 13, 16—first and second reducer;

14—second motor; 15—third motor; 17—rear wheel; 18—external charging plug;

Three different connection marks represent mechanical connections, signal connections, and electrical connections.

Specific implementation method

The present invention will be described in detail below in conjunction with the accompanying drawings and embodiments.

As shown in Figure 1, a distributed three-motor drive pure electric power system includes a first motor 5, a second motor 14, a third motor 15, a differential 1, a final drive 4, and two fixed speed ratio reducers reducer (first reducer 13 and second reducer 16), three inverters (first, second and third inverters 6, 11, 12), high voltage cabinet 8, charger 7, battery pack 10 and the whole Vehicle controller 9 and external charging connector 18; the first motor 5 is close to the output end of the front axle to output power to drive the front axle of the vehicle through the final drive 4 and differential 1, and the power transmission route is mechanically connected; The second motor 14 and the third motor 15 are all wheel motors, and the output shaft of the motor is decelerated and increased through the fixed speed ratio reducer 13, 16 to drive the rear axle of the vehicle. The power transmission route is mechanically connected; the external charging connector 18 can be connected with an external power socket, charge the battery 10 through the charger 7 and the high-voltage cabinet 8, and the charging circuit is electrically connected; the output terminal of the battery 10 is the first motor 5, The second motor 14 and the third motor 15 respectively provide electric energy, and the connection is an electrical connection; the vehicle controller 9 is connected to the battery pack including a battery management system BMS10, inverters 6, 11, 12, and a high-voltage cabinet 8 for signal connection , to control the entire electric drive system.

During the driving process of the vehicle, according to the load status of the vehicle, the vehicle controller controls the vehicle to drive in different driving modes. The driving modes include: front axle single motor drive mode, rear axle double motor common drive mode, front and rear axle three electric common drive , braking energy recovery mode and parking charging mode.

In the drive mode of the front axle single motor or the rear axle dual motors, one of the axle motors in the system drives the vehicle independently through the deceleration and torque increase when the vehicle load is low, and the other axle motor is turned off, making full use of the characteristics of the motor, not only It can meet the driving demand, and can also ensure that the motor has a high load rate and works in a high-efficiency range; the two-axis motor is jointly driven, and the three motors on the two axes of the system are single-axis when the vehicle load is relatively high. When the drive is difficult to meet the driving demand, the vehicle is jointly driven, and the load is distributed to the three motors on the front and rear axles. At this time, the three motors on the front and rear axles all have a high load rate and work in their respective high-efficiency zones; In the dynamic energy recovery mode, when the vehicle controller detects the braking signal, the three motors recover part of the braking energy and convert it into electric energy to charge the battery, with a higher braking energy recovery rate; in the parking charging mode, the vehicle is When parking, connect the external charging plug to the external charging socket to charge the battery to keep the battery fully charged.

In order to further understand the embodiment and content of the present invention, the present invention is described in detail through the accompanying drawings, specifically as follows:

1. Front axle single motor drive mode or rear axle dual motor drive mode

When the vehicle is running in a low-load condition (because the motors used in different models such as passenger cars and small cars are different, the low load and the subsequent high load can be determined after selecting the parameters of the motor for different vehicles. ), the vehicle controller controls one of the axis motors 5 or 14, 15 to turn on, and the other axis motor 14, 15 or 5 to turn off, and the turned on motor passes through its mechanical power transmission line motor (5 or 14, 15), reducer (4, 13, 16), axle shaft 2, and wheels to drive the vehicle. Compared with the traditional pure electric vehicle driven by a high-power motor alone, the load rate is low and the working efficiency of the motor is low. Instead, it is driven by a single motor with low power. It meets the driving requirements of the vehicle and ensures that the motor works in a relatively more efficient range. When the two wheel side motors of the rear axle are involved in the work and the vehicle is turning, the differential control of the rear axle double wheel side motors realizes the steering.

2. Common driving mode of three motors on the front and rear axles

When the vehicle is driving under high load conditions, the single-axis motor drive mode is difficult to meet the driving needs of the vehicle. At this time, the vehicle controller controls the three motors on the front and rear axles to turn on, and distributes the load to the three motors. The three motors pass through their respective The transmission system jointly drives the vehicle, so that the three motors have a higher load rate and work in their respective high-efficiency ranges. When the two wheel side motors of the rear axle are involved in the work and the vehicle is turning, the differential control of the rear axle double wheel side motors realizes the steering.

3. Brake energy recovery mode

When the vehicle controller detects the braking signal, the three motors of the front and rear axles jointly recover the energy generated during braking, and convert the mechanical energy into electrical energy and store it in the battery. Compared with the energy recovered by a single motor, the energy recovery rate is higher High, which is beneficial to shorten the braking distance.

4. Parking charging mode

When the vehicle is idle or the battery power is low and needs to be charged, the external charging plug 18 can be connected to the charging socket of the charging pile, and the battery is charged by the charger 7, the high-voltage cabinet 8, and the battery pack 10 to ensure that the battery power is full for use. When the battery is charged to the set charging limit, the vehicle controller will automatically cut off the charging circuit to prolong the service life of the battery.

Claims (6)

1. a kind of distributed three motor drives pure electric vehicle dynamical system, it is characterised in that：Including first motor, the second motor, It is three motors, differential mechanism, main reducing gear, two fixed speed ratio retarders, three inverters, high-voltage board, charger, battery pack, whole Vehicle controller, external charge connector；Before the first motor output end output power is through main reducing gear, differential mechanism driving vehicle Bridge, the power transmission line are mechanical connection；Second motor is wheel motor, motor output shaft warp with third motor Fixed speed ratio retarder deceleration torque, it is mechanical connection to drive vehicle rear axle, the power transmission line；The external charge connects Head can be connected with external electric supply socket, and charged machine, high-voltage board charge for battery pack, and the charging circuit is electrical connection；Institute It is that first motor, the second motor, third motor provide electric energy, the company respectively that battery pack output end, which is stated, through high-voltage board, inverter It is connected in electrical connection；The entire car controller and battery pack include that battery management system, inverter, high-voltage board signal are connect, right Entire power drive system is controlled.

2. three motor of distribution according to claim 1 drives pure electric vehicle dynamical system, it is characterised in that：First electricity Machine, the second motor, third motor respectively drive antero posterior axis, wherein one wheel motor of front axle, and two wheel motors of rear axle are same The power of the wheel motor of axis is identical, antero posterior axis motor can design success rate be identical according to demand or power is different, it is front and back The position of spindle motor can be exchanged for front axle bi-motor, rear axle single motor arrangement.

3. three motor of distribution according to claim 1 or 2 drives pure electric vehicle dynamical system, it is characterised in that：It is described Wheel motor output shaft on retarder type selecting and setting gear number according to demand, or be not provided with main deceleration according to demand Device, directly by motor-driven vehicle.

4. three motor of distribution according to claim 3 drives pure electric vehicle dynamical system, it is characterised in that：Described subtracts Fast device is fixed speed ratio retarder.

5. three motor of distribution according to claim 1 or 2 or 4 drives pure electric vehicle dynamical system, it is characterised in that：On The system of stating includes single motor drive mode, the common drive mode of bi-motor, the common drive mode of three motor of twin shaft, braking energy time Receipts pattern and stopping for charging pattern：Wherein, in the common drive mode of single motor drive mode, bi-motor, one of spindle motor Vehicle is operated alone when vehicle load is relatively low, makes full use of motor characteristic, and ensures that the motor has higher rate of load condensate, work Make in high efficiency range；Under the common drive mode of three motor of twin shaft, two axis, three motors drive jointly when vehicle load is higher Vehicle, at this time three motors all have higher rate of load condensate, be operated in respective high efficiency range；Under Brake energy recovery pattern, When entire car controller detects brake signal, by motor recovery section braking energy and electric energy is converted into as battery pack charging； Under stopping for charging pattern, vehicle external charge plug in parking connects external charge socket and charges to battery pack.

6. three motor of distribution according to claim 5 drives pure electric vehicle dynamical system, it is characterised in that：Above system Brake energy recovery pattern and stopping for charging pattern be not carried out at the same time.