CN110341498A - Distributed time-sharing four-wheel drive electric vehicle chassis configuration of in-wheel motor, four-wheel drive electric vehicle and control method - Google Patents

Abstract

The invention discloses a chassis configuration of a wheel hub motor distributed time-sharing four-wheel drive electric vehicle, a four-wheel drive electric vehicle and a control method. The invention comprises a frame assembly on which a first tire rim assembly, a third Second tire rim assembly, centralized motor, power battery pack, vehicle controller, high-voltage power distribution box, hub motor and radiator assembly, the first tire and rim assembly is connected with the centralized motor through the drive shaft and transmission, the second The wheel hub motor is installed on the tire rim assembly, the charger is electrically connected to the high-voltage power distribution box, the high-voltage power distribution box is electrically connected to the input end of the vehicle controller and the power battery pack, the vehicle controller is electrically connected to the hub motor, and the power The output end of the battery pack is respectively connected to the centralized motor and the hub motor through the inverter, and the inverter is electrically connected to the high-voltage power distribution box. The invention can meet the power requirements of different driving conditions and has high transmission efficiency.

Description

An in-wheel motor distributed time-sharing four-wheel drive electric vehicle chassis configuration, four-wheel drive electric vehicle Automobile and control method

technical field

The invention relates to a chassis configuration of a four-wheel drive electric vehicle, belonging to the technical field of automobile chassis, in particular to a chassis configuration of a wheel hub motor distributed time-sharing four-wheel drive electric vehicle.

Background technique

In order to cope with the energy shortage, people are paying more and more attention to new energy vehicles. Among new energy vehicles, electric vehicles have less impact on the environment than transmission vehicles, and their prospects are widely optimistic.

Pure electric vehicles are 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 and increases the difficulty of installation; on the other hand, electric vehicles are under different road conditions and working conditions. The power required by the motor is different. Simple front-wheel drive, rear-wheel drive or four-wheel drive cannot maximize the use of motor characteristics, which reduces the efficiency of the motor. Two-wheel drive electric vehicles have poor performance such as climbing ability, limited ability to adapt to complex road conditions, and the existing battery energy density is limited, the vehicle driving range is short, and a large internal space is required when arranging batteries, resulting in reduced ride comfort.

At present, the power system of electric vehicles usually has two configurations, one is a single motor driving the whole vehicle (front axle or rear axle is equipped with a centralized motor), the other is a dual motor driving the whole vehicle (the front and rear axles are equipped with a centralized motor each) ).

However, both powertrains have certain drawbacks. The power system driven by a centralized motor cannot keep the motor on the optimal efficiency curve under various working conditions, and cannot maximize the motor efficiency; and a single motor needs to consider various working conditions, resulting in power range and deceleration. The ratio is relatively large, so that the motor is large and heavy; the power system of the dual-motor drive vehicle can make the motor work in the high-efficiency area as much as possible, but when the electric vehicle is at low speed and the power demand is not large, if two sets of motors are used. Driving at the same time will result in poor vehicle economy.

SUMMARY OF THE INVENTION

In order to solve the deficiencies of the above technologies, the present invention provides a chassis configuration of an in-wheel motor distributed time-sharing four-wheel drive electric vehicle, which can simplify the chassis structure, facilitate installation, etc., and can meet the power requirements of different driving conditions and has high transmission efficiency. , the driving mode can be switched according to the actual working conditions of the vehicle to improve the economy of the whole vehicle.

The invention discloses a vehicle frame assembly including a vehicle frame assembly, on which a first tire rim assembly, a second tire rim assembly, a centralized motor, a power battery pack, a complete vehicle are arranged A controller, a high-voltage power distribution box, a hub motor and a radiator assembly, the first tire rim assembly is drive-connected with the centralized motor through a drive shaft and a transmission, and the second tire rim assembly is mounted on the In-wheel motor, the charger is electrically connected with the high-voltage power distribution box, the high-voltage power distribution box is electrically connected with the vehicle controller and the input end of the power battery pack, and the vehicle controller is electrically connected with the The in-wheel motor is electrically connected, and the output end of the power battery pack is respectively connected to the centralized motor and the in-wheel motor through an inverter, and the inverter is electrically connected to the high-voltage power distribution box.

In a preferred embodiment of the present invention, the output end of the centralized motor is drive-connected to the input end of the reducer, the output end of the reducer is drive-connected to the drive shaft, and the drive shaft is connected to the drive shaft. The first tire rim assembly is connected.

In a preferred embodiment of the present invention, the high-voltage power distribution box is electrically connected with a charger with an external charging connector.

In a preferred embodiment of the present invention, there are three inverters.

In a preferred embodiment of the present invention, a front suspension assembly is arranged beside the first tire rim assembly.

In a preferred embodiment of the present invention, a rear suspension assembly is arranged beside the second tire rim assembly.

The invention also discloses a four-wheel drive electric vehicle, which includes the in-wheel motor distributed time-sharing four-wheel drive electric vehicle chassis configuration as described in claims 1-8.

The invention also discloses a control method for a four-wheel-drive electric vehicle, which is the aforementioned four-wheel-drive electric vehicle. The four-wheel-drive electric vehicle improves the handling performance of the whole vehicle through coordinated control of the torque of the whole vehicle; the four-wheel drive electric vehicle is used as the controlled object , receive the four-wheel drive torque determined by the control algorithm of the vehicle controller and respond; the vehicle feedback the vehicle speed, acceleration, yaw angular velocity and vehicle body state parameters to give a control algorithm, and the control steps include: using the vehicle kinematics control algorithm, The yaw angular velocity is controlled by the control algorithm to approach or reach the ideal yaw angular velocity, and the additional yaw moment required at this time is determined, and then the torque of the hub motor and the centralized motor is distributed through the torque distribution strategy. , to achieve four-wheel torque compensation of pure electric vehicles and achieve precise torque control.

The working principle of the present invention is as follows: when the vehicle is running in a low-load condition, the two in-wheel motors of the system drive the vehicle independently, and the centralized motor of the other axle is turned off and only acts as a driven wheel to meet the driving requirements of the vehicle; In other situations, such as driving on different roads or climbing slopes, the two-wheel motor drive work cannot meet the demand. At this time, the centralized motor starts to participate in the work, and the dual-axle three-motor four-wheel drive mode is turned on, and the vehicle controller will load according to a certain amount. The control strategy is assigned to three motors, so that the three motors have a higher load rate; when the vehicle brakes, the motors recover braking energy, which improves the braking energy recovery rate and shortens the braking distance.

The beneficial effects of the present invention are:

1. A new type of electric drive chassis configuration is proposed, including one centralized motor for the front axle and two in-wheel motors for the rear axle. Under the premise of ensuring the overall dynamic performance of the vehicle remains unchanged, the two-wheel drive/four-wheel drive mode can be realized. Free switching, adapt to different working conditions, under the same vehicle load conditions, significantly improve the working efficiency of the motor;

2. Under the braking condition, based on the fast response characteristics of the in-wheel motor, it is convenient to realize the decoupling braking energy recovery and improve the safety and economy of the whole vehicle;

3. The use of distributed layout can reduce the number of vehicle transmission system components, simplify the chassis layout, improve the lightweight space, improve the transmission efficiency of the vehicle, reduce energy consumption, and improve the vehicle cruising range;

4. Distributed drive arrangement can improve vehicle handling performance through coordinated control of vehicle torque. As the controlled object, the four-wheel drive electric vehicle receives the four-wheel drive torque determined by the control algorithm of the vehicle controller and responds; the vehicle feeds back the vehicle body state parameters such as vehicle speed, acceleration, and yaw rate to give the control algorithm. First, through the calculation of the state parameters and variables of the vehicle body, the equivalent cornering stiffness and vertical load distribution of the front and rear axles are calculated; then, through the design of the steering characteristics, the ideal value of the yaw angular velocity is set as the following control target of the vehicle controller . Specifically, it is to use the vehicle kinematics control algorithm to control the actual yaw angular velocity, and adjust through the control algorithm to approach or achieve the ideal yaw angular velocity, determine the additional yaw moment required at this time, and then pass The torque distribution strategy distributes the torque of the in-wheel motor and the centralized motor to realize the four-wheel torque compensation of pure electric vehicles and achieve precise torque control.

Description of drawings

Fig. 1 is the electric vehicle chassis configuration schematic diagram of the distributed time-sharing four-wheel drive of the in-wheel motor of the present invention;

In the picture: 1-front suspension assembly; 2-radiator assembly; 3-first tire rim assembly; 4-drive shaft; 5-centralized motor; 6-inverter; 7-power battery pack; 8 -2nd tire rim assembly; 9-wheel hub motor; 10-rear suspension assembly; 11-vehicle controller; 12-high voltage distribution box; 13-charger; 14-external charging interface; 15-reducer ; 16 - Frame assembly.

Detailed ways

In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention, but not to limit the present invention.

As shown in the figure, an in-wheel motor distributed time-sharing four-wheel drive electric vehicle chassis configuration includes a centralized motor 6, a reducer 15, a drive shaft 4, two in-wheel motors 9, three inverters 6, a high-voltage distribution Electric box 12, charger 13, external charging interface 14, power battery pack 7, vehicle controller 11, radiator assembly 2, front suspension assembly 1, rear suspension assembly 10, first tire rim assembly 3 and the second tire rim assembly 8, the frame assembly 16; the output power of the concentrated motor 6 is connected to the first tire rim assembly 3 through the reducer 15 and the two drive shafts 4 to drive the vehicle forward; the two hub motors 9 It is installed on the second tire rim assembly 8, and directly drives the second tire rim assembly 8; the external charging connector 14 can be connected to an external power socket, and charges the power battery pack 7 through the charger 13 and the high-voltage power distribution box 12; The output end of the battery pack 7 provides electrical energy to the centralized motor 6 and the hub motor 9 through the high-voltage power distribution box 12; The system is controlled; the radiator assembly 2 cools the centralized motor 6 and the hub motor 9 through water cooling; the front suspension assembly 1 is connected to the frame assembly 16 and the first tire rim assembly 3 to provide steering, load-bearing, reducing power for the vehicle. shock; the rear suspension assembly 10 connects the frame assembly 16 and the second tire rim assembly 8 to provide load bearing and shock absorption for the vehicle; the frame assembly 16 provides a support connection for the entire chassis structure.

During the driving process of the vehicle, according to the working conditions of the vehicle, the vehicle controller controls the vehicle to drive in different driving modes. The driving modes include: single-axle two-wheel motor drive mode, double-axle three-motor four-wheel drive mode, braking energy recovery mode and parking charge mode.

In the single-axle two-wheel-wheel motor drive mode, when the vehicle is running in a low-load condition, the system's two in-wheel motors drive the vehicle independently, and the centralized motor of the other axle is turned off and only acts as a driven wheel to meet the vehicle's driving needs; In high-load conditions, such as driving on a different road or climbing a slope, the two-wheel motor drive cannot meet the demand. At this time, the centralized motor starts to participate in the work, and the dual-axle three-motor four-wheel drive mode is turned on, and the vehicle controller will load according to the load. A certain control strategy is assigned to the three motors, so that the three motors have a higher load rate; in the braking energy recovery mode, when the vehicle is braking, the motor recovers the braking energy, and the braking energy of the in-wheel motor is recovered. It is converted into electric energy to charge the power battery, which improves the braking energy recovery rate and shortens the braking distance; in the parking charging mode, when the vehicle is parked, the external charging interface is connected to the external charging interface to charge the battery.

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

1. Single-axle two-wheel motor drive mode

When the vehicle is running under low load conditions, the vehicle controller only turns on the single-axle two-wheel-wheel motor drive mode, the centralized motor system is turned off, and the wheel-wheel motor directly drives the tire and rim assembly. Compared with traditional pure electric vehicles, it can not only meet the needs of the vehicle Driving demand, and the power transmission chain is short, the transmission mechanical efficiency is high, and the working efficiency of the motor is also high.

2. Dual-bridge three-motor four-wheel drive mode

When the vehicle is driven in a high-load condition, such as a road with different attachments or a climbing road, the dual-wheel-hub motor may be difficult to meet the driving demand of the vehicle. At this time, the vehicle controller monitors the power output of the vehicle and turns on the centralized motor in time. , the centralized motor outputs the power through the two drive shafts to the tire and rim assemblies on the left and right sides through the reducer. In the double-axle three-motor four-wheel drive mode, the three motors have a high load rate and work in their respective high-efficiency ranges. Inside.

3. Braking energy recovery mode

When the vehicle controller detects the braking capacity recovery signal, the braking energy recovery system of the motor is turned on at this time, which converts a part of the mechanical energy into electrical energy during braking, and charges the power battery pack through the inverter, which improves the braking energy. The recovery rate is beneficial to shorten the braking distance.

4. Parking and charging mode

When the vehicle is idle or the battery power is too low, the vehicle needs to be charged at this time. You can connect the external charging interface to the charging pile charging interface, and charge the battery pack through the charger, high-voltage power distribution box, and battery pack. When charging to the set charging upper limit, the vehicle controller will automatically cut off the charging circuit to prolong the practical life of the battery.

5. Distributed vehicle torque coordination control

As the controlled object, the four-wheel drive electric vehicle receives the four-wheel drive torque determined by the control algorithm of the vehicle controller and responds; the vehicle feeds back the vehicle body state parameters such as vehicle speed, acceleration, and yaw rate to give the control algorithm. First, through the calculation of the state parameters and variables of the vehicle body, the equivalent cornering stiffness and vertical load distribution of the front and rear axles are calculated; then, through the design of the steering characteristics, the ideal value of the yaw angular velocity is set as the following control target of the vehicle controller . Specifically, it is to use the vehicle kinematics control algorithm to control the actual yaw angular velocity, and adjust through the control algorithm to approach or achieve the ideal yaw angular velocity, determine the additional yaw moment required at this time, and then pass The torque distribution strategy distributes the torque of the in-wheel motor and the centralized motor to realize the four-wheel torque compensation of pure electric vehicles and achieve precise torque control.

The above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention should be covered. within the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope defined by the claims.

Claims (10)

1. A chassis configuration of an in-wheel motor distributed time-sharing four-wheel drive electric vehicle, comprising a frame assembly, which is provided with a first tire rim assembly, a second tire rim assembly, a centralized motor, A power battery pack, a vehicle controller, a high-voltage power distribution box, a hub motor and a radiator assembly, the first tire rim assembly is connected to the centralized motor through a drive shaft and a transmission, and the second tire rim assembly is connected to the centralized motor. The in-wheel motor is installed on it, and it is characterized in that: the charger is electrically connected to the high-voltage power distribution box, and the high-voltage power distribution box is electrically connected to the vehicle controller and the input end of the power battery pack. The vehicle controller is electrically connected to the in-wheel motor and the centralized motor controller, the output end of the power battery pack is connected to the centralized motor and the in-wheel motor respectively through an inverter, and the inverse The transformer is electrically connected to the high-voltage distribution box. 2 . The in-wheel motor distributed time-sharing four-wheel drive electric vehicle chassis configuration according to claim 1 , wherein the in-wheel motor is connected to the second tire rim assembly. 3 . 3. The in-wheel motor distributed time-sharing four-wheel drive electric vehicle chassis configuration according to claim 1, characterized in that: the output end of the centralized motor is drive-connected to the input end of the reducer, and the deceleration The output end of the device is in driving connection with the drive shaft, and the drive shaft is connected with the first tire rim assembly. 4 . The in-wheel motor distributed time-sharing four-wheel drive electric vehicle chassis configuration according to claim 1 , wherein the radiator assembly is connected to the centralized motor and the in-wheel motor through a cooling pipeline. 5 . . 5 . The in-wheel motor distributed time-sharing four-wheel drive electric vehicle chassis configuration according to claim 1 , wherein the high-voltage power distribution box is electrically connected with a charger with an external charging connector. 6 . 6 . The in-wheel motor distributed time-sharing four-wheel drive electric vehicle chassis configuration according to claim 1 , wherein there are three inverters. 7 . 7 . The in-wheel motor distributed time-sharing four-wheel drive electric vehicle chassis configuration according to claim 1 , wherein the first tire rim assembly is connected to the frame assembly through a front suspension assembly. 8 . 8 . The in-wheel motor distributed time-sharing four-wheel drive electric vehicle chassis configuration according to claim 1 , wherein the second tire rim assembly is connected to the frame assembly through a rear suspension assembly. 9 . 9. A four-wheel drive electric vehicle, characterized in that it comprises the in-wheel motor distributed time-sharing four-wheel drive electric vehicle chassis configuration according to any one of claims 1-8. 10. A control method for a four-wheel-drive electric vehicle, characterized in that: it is the four-wheel-drive electric vehicle as claimed in claim 9, and the four-wheel drive electric vehicle improves the handling performance of the whole vehicle through coordinated control of the torque of the whole vehicle; As the controlled object, the electric vehicle receives the four-wheel drive torque determined by the control algorithm of the vehicle controller and responds; the vehicle feeds back the vehicle speed, acceleration, and yaw rate and the vehicle body state parameters to give the control algorithm. The control steps include: adopting the motion of the vehicle Learn the control algorithm, control the actual yaw angular velocity, and adjust through the control algorithm to approach or achieve the ideal yaw angular velocity, and determine the additional yaw moment required at this time, and then use the torque distribution strategy to adjust the hub motor and the hub motor. The torque of the centralized motor is distributed to realize the four-wheel torque compensation of pure electric vehicles and achieve precise torque control.