CN112977090A

CN112977090A - Driving control method and device of electric automobile and electric automobile

Info

Publication number: CN112977090A
Application number: CN202110291772.5A
Authority: CN
Inventors: 舒晖; 陈士刚; 李庆国; 陶文勇; 钱兆刚; 杭孟荀; 刘琳; 沙文瀚
Original assignee: Chery New Energy Automobile Co Ltd
Current assignee: Chery New Energy Automobile Co Ltd
Priority date: 2021-03-18
Filing date: 2021-03-18
Publication date: 2021-06-18

Abstract

The application discloses a driving control method and device of an electric automobile and the electric automobile, wherein the method comprises the following steps: detecting whether the electric automobile enters a single-pedal control driving mode or not; when the single-pedal control driving mode is detected, acquiring the current acceleration opening and the current braking opening of an accelerator pedal and a brake pedal; if the current braking opening degree is smaller than or equal to a first preset threshold value and the current acceleration opening degree is larger than a second preset threshold value, after the driving motor is controlled to output the corresponding acceleration torque according to the current acceleration opening degree and the current acceleration opening degree returns to zero, the driving motor is controlled to output the braking torque, and the energy recovery is carried out while the electric automobile is braked. Therefore, the problem of parking of the electric automobile in a single-pedal driving mode in the related technology is solved, the driving mode is controlled through a single pedal, the use frequency of a brake pedal is reduced through the motor-controlled parking function, and the driving convenience and the energy utilization efficiency of the electric automobile are improved.

Description

Driving control method and device of electric automobile and electric automobile

Technical Field

The application relates to the technical field of vehicles, in particular to a driving control method and device of an electric automobile and the electric automobile.

Background

At present, electric vehicles have gradually become a tool for people to ride instead of walk, and with the increasing preservation of electric vehicles in the market, the driving convenience of electric vehicles is the focus of attention of most vehicle owners. Because electric automobile mostly is the single reduction gear drive, generally adopts two footboard structures, wherein, accelerator pedal is used for driving the vehicle acceleration, and brake pedal controls the vehicle braking and parks.

In the related technology, the control travel of the accelerator pedal is divided into a braking section 0-A, a sliding section A-B and an accelerating section B-100%, so that the operation of the single pedal meets the requirements of normal running conditions such as advancing, sliding and braking of a vehicle, and the single-pedal driving mode is realized.

However, in the single-pedal driving mode, the parking process of the electric vehicle still needs to rely on the brake pedal to achieve parking through mechanically locking the wheels, and therefore, the parking problem in the single-pedal driving mode of the electric vehicle is to be solved.

Content of application

The application provides a driving control method and device of an electric automobile and the electric automobile, so that the problem of parking of the electric automobile in a single-pedal driving mode is solved, the driving mode is controlled through a single pedal, the parking function controlled by a motor is relied on, the use frequency of a brake pedal is reduced, and the driving convenience and the energy utilization efficiency of the electric automobile are improved.

An embodiment of a first aspect of the present application provides a driving control method for an electric vehicle, including the following steps:

detecting whether the electric automobile enters a single-pedal control driving mode or not;

when the single-pedal control driving mode is detected, acquiring the current acceleration opening and the current braking opening of an accelerator pedal and a brake pedal;

if the current braking opening degree is smaller than or equal to a first preset threshold value and the current acceleration opening degree is larger than a second preset threshold value, after the driving motor is controlled to output corresponding acceleration torque according to the current acceleration opening degree and the current acceleration opening degree returns to zero, the driving motor is controlled to output braking torque, and energy recovery is carried out while the electric automobile is braked.

Optionally, the first preset threshold and the second preset threshold are both zero.

Optionally, the method further comprises:

acquiring the actual rotating speed of the electric automobile;

and when the actual rotating speed is lower than the preset rotating speed, controlling the driving motor to enter a parking mode so as to control the driving motor to be in a zero rotating speed state based on the current gradient of the electric automobile.

Optionally, the detecting whether the electric vehicle is in the single-pedal control driving mode includes:

detecting whether the electric automobile meets a single-pedal control condition;

and if the electric automobile meets the single-pedal control condition, controlling the electric automobile to enter the single-pedal control driving mode according to the single-pedal control request.

Optionally, the detecting whether the electric vehicle meets the single-pedal control condition includes:

detecting whether the electric automobile is in a Ready state or not;

detecting whether the current gear of the electric automobile is a D gear or not;

detecting whether the working state of a water pump of the electric automobile is a normal working state or not;

detecting whether an electric drive system of the electric automobile is in failure;

detecting whether the electric automobile is in an energy recovery prohibition state.

An embodiment of a second aspect of the present application provides a driving control device for an electric vehicle, including:

the detection module is used for detecting whether the electric automobile enters a single-pedal control driving mode or not;

the first obtaining module is used for obtaining the current acceleration opening and the current braking opening of an accelerator pedal and a brake pedal when the single-pedal control driving mode is detected;

the first control module is used for controlling the driving motor to output the braking torque when the current braking opening degree is smaller than or equal to a first preset threshold value and the current acceleration opening degree is larger than a second preset threshold value and controlling the driving motor to output the corresponding acceleration torque according to the current acceleration opening degree and controlling the driving motor to output the braking torque when the current acceleration opening degree returns to zero, and the electric automobile is braked and energy recovery is carried out.

Optionally, the method further comprises:

the second acquisition module is used for acquiring the actual rotating speed of the electric automobile;

and the second control module is used for controlling the driving motor to enter a parking mode when the actual rotating speed is lower than a preset rotating speed so as to control the driving motor to be in a zero rotating speed state based on the current gradient of the electric automobile.

Optionally, the detection module includes:

the detection unit is used for detecting whether the electric automobile meets a single-pedal control condition;

and the control unit is used for controlling the electric automobile to enter the single-pedal control driving mode according to the single-pedal control request when the electric automobile meets the single-pedal control condition.

Optionally, the detection unit includes:

detecting whether the electric automobile is in a Ready state or not;

In an embodiment of the third aspect of the present application, an electric vehicle is provided, which includes the driving control device of the electric vehicle.

Therefore, when the electric automobile is detected to be in the single-pedal control driving mode, the current acceleration opening and the current braking opening of the accelerator pedal and the brake pedal can be obtained, when the current braking opening is smaller than a certain value and is larger than a certain value, after the driving motor is controlled to output the corresponding acceleration torque according to the current acceleration opening, the current acceleration opening returns to zero, the driving motor is controlled to output the braking torque, energy recovery is carried out while the electric automobile is braked, the problem of parking in the single-pedal driving mode of the electric automobile in the related art is solved, in the single-pedal control driving mode, the parking function controlled by the motor is relied on, the use frequency of the brake pedal is reduced, and the driving convenience and the energy utilization efficiency of the electric automobile are improved.

Additional aspects and advantages of the present application will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the present application.

Drawings

The foregoing and/or additional aspects and advantages of the present application will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

fig. 1 is a flowchart of a driving control method of an electric vehicle according to an embodiment of the present application;

FIG. 2 is a flow chart of a control method for a single pedal controlled driving mode according to one embodiment of the present application;

FIG. 3 is a flow chart of a motor park function according to one embodiment of the present application;

fig. 4 is an exemplary diagram of a driving control apparatus of an electric vehicle according to an embodiment of the present application.

Detailed Description

Reference will now be made in detail to embodiments of the present application, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are exemplary and intended to be used for explaining the present application and should not be construed as limiting the present application.

The following describes a driving control method and device for an electric vehicle and the electric vehicle according to an embodiment of the present application with reference to the drawings. In order to solve the parking problem of the electric vehicle in the single-pedal driving mode mentioned in the above background art center, the present application provides a driving control method of an electric vehicle, in which when it is detected that the electric vehicle is in the single-pedal driving mode, the current accelerator opening and the current brake opening of the accelerator pedal and the brake pedal are obtained, and when the current brake opening is smaller than a certain value and the current accelerator opening is greater than a certain value, after the driving motor is controlled to output the corresponding accelerator torque according to the current accelerator opening and the current accelerator opening returns to zero, the driving motor is controlled to output the brake torque, and energy recovery is performed while the electric vehicle is braked, thereby solving the parking problem of the electric vehicle in the single-pedal driving mode, and depending on the parking function controlled by the motor, the usage frequency of the brake pedal is reduced, the driving convenience and the energy utilization efficiency of the electric automobile are improved.

Specifically, fig. 1 is a schematic flow chart of a driving control method of an electric vehicle according to an embodiment of the present application.

As shown in fig. 1, the driving control method of the electric vehicle includes the steps of:

in step S101, it is detected whether the electric vehicle enters the single-pedal control driving mode.

Optionally, in some embodiments, detecting whether the electric vehicle is in the single-pedal control driving mode comprises: detecting whether the electric automobile meets a single-pedal control condition; and if the electric automobile meets the single-pedal control condition, controlling the electric automobile to enter a single-pedal control driving mode according to the single-pedal control request.

It should be understood that the embodiment of the present application may detect, by the controller, whether the electric vehicle satisfies the single-pedal control condition, for example, detect whether the electric vehicle is in the Ready state; detecting whether the current gear of the electric automobile is a D gear; detecting whether the working state of a water pump of the electric automobile is a normal working state or not; detecting whether an electric drive system of the electric automobile breaks down; whether the electric vehicle is in an energy recovery prohibition state is detected.

For example, if the electric vehicle is not in the Ready state, it indicates that the electric vehicle does not enter the single-pedal control driving mode; if the electric automobile is in a Ready state, the current gear of the electric automobile is a D gear, the working state of a water pump of the electric automobile is a normal working state, an electric drive system of the electric automobile is not in fault, the electric automobile is in a state of prohibiting energy recovery and the like, the electric automobile meets the single-pedal control condition, and the electric automobile enters a single-pedal control driving mode.

In step S102, upon detection of being in the single-pedal control driving mode, current accelerator opening degrees and current brake opening degrees of an accelerator pedal and a brake pedal are acquired.

After the electric automobile enters a single-pedal control driving mode, the vehicle control unit can receive signals of an accelerator pedal and a brake pedal in real time.

In step S103, if the current braking opening degree is less than or equal to the first preset threshold value and the current acceleration opening degree is greater than the second preset threshold value, after the driving motor is controlled to output the corresponding acceleration torque according to the current acceleration opening degree and the current acceleration opening degree returns to zero, the driving motor is controlled to output the braking torque, and energy recovery is performed while the electric vehicle is braked.

The first preset threshold and the second preset threshold may be thresholds preset by a user, may be thresholds obtained through limited experiments, or may be thresholds obtained through limited computer simulation.

Preferably, in some embodiments, the first preset threshold and the second preset threshold are both zero.

Specifically, when the electric automobile is detected to be in a single-pedal control driving mode, the vehicle control unit acquires signals of an accelerator pedal and a brake pedal (namely, the current accelerator opening and the current brake opening) in real time, and if the current brake opening is smaller than or equal to 0 and the current accelerator opening is larger than 0, the vehicle control unit adjusts a torque command according to the current accelerator opening and controls a driving system to output a torque to drive the vehicle; when the current acceleration opening degree is 0, the vehicle control unit requests the braking torque to control the driving system to recover energy, and vehicle braking is realized.

Optionally, in some embodiments, the method further comprises: acquiring the actual rotating speed of the electric automobile; and when the actual rotating speed is lower than the preset rotating speed, controlling the driving motor to enter a parking mode so as to control the driving motor to be in a zero rotating speed state based on the current gradient of the electric automobile.

That is to say, when the vehicle speed is braked below the preset rotation speed, the vehicle Controller requests the motor Controller to enter the parking function, the motor Controller receives CAN (Controller Area Network) signals of the vehicle Controller and the ramp sensor in real time, and the motor is controlled to be stabilized at the zero rotation speed, so that the vehicle is parked.

In order to enable those skilled in the art to further understand the driving control method of the electric vehicle according to the embodiment of the present application, the following description is made in detail with reference to fig. 2 and 3.

The driving control method of the electric automobile according to the embodiment of the application mainly comprises the following hardware: the system comprises a vehicle control unit, a motor controller, a motor, an accelerator pedal, a brake pedal, a ramp sensor and a single-pedal driving mode switch. Under the single-pedal control driving mode, the vehicle control unit receives CAN signals of the motor controller, the accelerator pedal, the brake pedal and the ramp sensor through a CAN network and controls the electric vehicle to work under the working conditions of acceleration, braking and parking.

Specifically, as shown in fig. 2, fig. 2 is a flowchart of a control method of a single-pedal control driving mode according to an embodiment of the present application. The method comprises the following steps:

and S201, completing the vehicle Ready.

S202, the vehicle control unit judges whether a single-pedal control driving mode switch is turned on, if so, step S203 is executed, otherwise, step S204 is executed.

S203, the vehicle controller judges whether the current state of the vehicle meets the single-pedal control driving mode, if so, step S205 is executed, otherwise, step S204 is executed.

The whole vehicle current state judgment comprises whether a current gear is in a D gear, whether a brake pedal is stepped, whether a water pump works normally, whether an electric drive system has a fault, whether the whole vehicle is forbidden to recover energy and the like.

And S204, operating the electric automobile in a normal driving mode.

S205, the vehicle controller detects whether the opening degree of an accelerator pedal is larger than 0, if so, step S206 is executed, otherwise, step S207 is executed.

And S206, operating the electric automobile in an acceleration process.

And S207, operating the electric automobile in a braking process.

And S208, judging whether the rotating speed of the motor is less than the preset rotating speed N, if so, executing a step S209, otherwise, executing a step S207.

And S209, operating the electric automobile in a parking process.

As shown in fig. 3, fig. 3 is a flowchart of a motor stop function according to an embodiment of the present application, including the following steps:

s301, the vehicle control unit requests the motor controller to enter a parking function

Specifically, the electric automobile starts a single-pedal control driving mode, and after an accelerator pedal is released, when the rotating speed of a motor is lower than a preset rotating speed N when the whole automobile is braked, a whole automobile controller requests the motor controller to enter a parking function; the motor rotating speed N is related to the gradient value, and the larger the gradient value acquired by the gradient sensor is, the larger the value of the motor rotating speed N is.

S302, after receiving a command of the whole vehicle controller through the CAN bus, the motor controller judges whether the current state of the electric drive system meets the function of entering the parking, if so, the step S304 is executed, otherwise, the step S303 is executed.

The current state judgment of the electric drive system mainly comprises a motor controller, whether the motor has a fault currently and whether the current rotating speed of the motor is within a safe rotating speed.

And S303, the motor controller quits the parking function and controls the vehicle to work normally.

S304, the motor controller judges whether the current rotating speed of the motor is less than 0rpm, if so, step S309 is executed, otherwise, step S305 is executed.

S305, the motor controller performs a preload torque operation according to the gradient value.

That is, the motor controller of the embodiment of the present application may control the motor to perform the preload torque operation, i.e., to be incremented from the current torque to the preload target torque at a fixed gradient; the magnitude of the preloading target torque is related to the gradient value, and is the torque required by the electric automobile to be stabilized at the current gradient.

S306, the motor controller judges whether the preloading torque operation is finished, if so, the step S307 is executed, otherwise, the step S305 is executed.

And judging that the preloading torque operation is finished when the error between the current output torque of the motor and the preloading target torque is within +/-1 Nm.

S307, the motor controller judges whether the current rotating speed of the motor is less than 0rpm, if so, step S309 is executed, otherwise, step S308 is executed.

S308, the motor controller controls the output torque of the motor to decrease progressively with a fixed gradient until the current rotating speed of the motor is less than 0 rpm.

And S309, enabling the motor controller to enter a rotating speed loop for regulation, and controlling the vehicle to stop.

In the rotating speed loop adjusting process, the target rotating speed of the motor is set to be 0rpm, the difference value between the target rotating speed and the current rotating speed is used as input, the control torque adjusted by the PI is used as output, and the rotating speed of the motor is controlled to be stabilized at 0 rpm.

S310, the motor controller judges whether the parking function exit condition is met, if yes, step S311 is executed, otherwise, step S312 is executed.

Wherein, whether the quit condition of the parking function is satisfied is judged by whether the vehicle controller requests to quit the function, whether the electric drive system is in failure and whether the current rotating speed exceeds the safe rotating speed,

and S311, the motor controller quits the parking function, and the vehicle works normally.

And S312, maintaining the parking function by the motor controller and keeping the vehicle static.

It should be noted that the acceleration process and the braking process of the electric vehicle may refer to the control manner in the related art, and detailed description is omitted here to avoid redundancy.

According to the driving control method of the electric automobile, when the electric automobile is detected to be in the single-pedal control driving mode, the current acceleration opening and the current braking opening of the accelerator pedal and the brake pedal can be obtained, when the current braking opening is smaller than a certain value and the current acceleration opening is larger than a certain value, after the driving motor is controlled to output the corresponding acceleration torque according to the current acceleration opening, the driving motor is controlled to output the braking torque when the current acceleration opening returns to zero, energy recovery is carried out while the electric automobile is braked, the problem of parking of the electric automobile in the single-pedal driving mode in the related technology is solved, the driving mode is controlled through the single pedal, the parking function controlled through the motor is adopted, the use frequency of the brake pedal is reduced, and the driving convenience and the energy utilization efficiency of the electric automobile are improved.

Next, a driving control apparatus of an electric vehicle according to an embodiment of the present application will be described with reference to the drawings.

Fig. 4 is a block diagram schematically illustrating a driving control apparatus for an electric vehicle according to an embodiment of the present application.

As shown in fig. 4, the drive control device 10 for an electric vehicle includes: a detection module 100, a first acquisition module 200, and a first control module 300.

The detection module 100 is configured to detect whether the electric vehicle enters a single-pedal control driving mode;

the first obtaining module 200 is configured to obtain current accelerator opening degrees and current brake opening degrees of an accelerator pedal and a brake pedal when detecting that the single-pedal control driving mode is adopted;

the first control module 300 is configured to, when the current braking opening degree is less than or equal to a first preset threshold and the current acceleration opening degree is greater than a second preset threshold, control the driving motor to output the braking torque after controlling the driving motor to output the corresponding acceleration torque according to the current acceleration opening degree and when the current acceleration opening degree returns to zero, perform energy recovery while braking the electric vehicle

Optionally, the method further comprises:

and the second control module is used for controlling the driving motor to enter a parking mode when the actual rotating speed is lower than the preset rotating speed so as to control the driving motor to be in a zero rotating speed state based on the current gradient of the electric automobile.

Optionally, the detection module 100 comprises:

the detection unit is used for detecting whether the electric automobile meets the single-pedal control condition;

and the control unit is used for controlling the electric automobile to enter a single-pedal control driving mode according to the single-pedal control request when the electric automobile meets the single-pedal control condition.

Optionally, the detection unit comprises:

detecting whether the electric automobile is in a Ready state or not;

detecting whether the current gear of the electric automobile is a D gear;

detecting whether an electric drive system of the electric automobile breaks down;

whether the electric vehicle is in an energy recovery prohibition state is detected.

It should be noted that the foregoing explanation of the embodiment of the driving control method for an electric vehicle is also applicable to the driving control device for an electric vehicle in this embodiment, and will not be repeated here.

According to the driving control device of the electric automobile provided by the embodiment of the application, when the electric automobile is detected to be in the single-pedal control driving mode, the current acceleration opening and the current braking opening of the accelerator pedal and the brake pedal can be obtained, when the current braking opening is smaller than a certain value and the current acceleration opening is larger than a certain value, after the driving motor is controlled to output the corresponding acceleration torque according to the current acceleration opening, the current acceleration opening returns to zero, the driving motor is controlled to output the braking torque, energy recovery is carried out while the electric automobile is braked, the problem of parking of the electric automobile in the single-pedal driving mode in the related technology is solved, the driving mode is controlled by the single pedal, the parking function controlled by the motor is relied on, the use frequency of the brake pedal is reduced, and the driving convenience and the energy utilization efficiency of the electric automobile are improved.

In addition, the embodiment of the application also provides an electric automobile which comprises the driving control device of the electric automobile.

According to the electric automobile provided by the embodiment of the application, the problem of parking under a single-pedal driving mode of the electric automobile in the related technology is solved through the driving control device of the electric automobile, the driving mode is controlled through a single pedal, the parking function controlled by a motor is utilized, the use frequency of a brake pedal is reduced, and the driving convenience and the energy utilization efficiency of the electric automobile are improved.

In the description herein, reference to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the application. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or N embodiments or examples. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present application, "N" means at least two, e.g., two, three, etc., unless specifically limited otherwise.

Any process or method descriptions in flow charts or otherwise described herein may be understood as representing modules, segments, or portions of code which include one or more N executable instructions for implementing steps of a custom logic function or process, and alternate implementations are included within the scope of the preferred embodiment of the present application in which functions may be executed out of order from that shown or discussed, including substantially concurrently or in reverse order, depending on the functionality involved, as would be understood by those reasonably skilled in the art of implementing the embodiments of the present application.

It should be understood that portions of the present application may be implemented in hardware, software, firmware, or a combination thereof. In the above embodiments, the N steps or methods may be implemented in software or firmware stored in a memory and executed by a suitable instruction execution system. If implemented in hardware, as in another embodiment, any one or combination of the following techniques, which are known in the art, may be used: a discrete logic circuit having a logic gate circuit for implementing a logic function on a data signal, an application specific integrated circuit having an appropriate combinational logic gate circuit, a Programmable Gate Array (PGA), a Field Programmable Gate Array (FPGA), or the like.

It will be understood by those skilled in the art that all or part of the steps carried by the method for implementing the above embodiments may be implemented by hardware related to instructions of a program, which may be stored in a computer readable storage medium, and when the program is executed, the program includes one or a combination of the steps of the method embodiments.

Claims

1. A driving control method of an electric vehicle is characterized by comprising the following steps:

2. The method of claim 1, wherein the first preset threshold and the second preset threshold are both zero.

3. The method of claim 1, further comprising:

acquiring the actual rotating speed of the electric automobile;

4. The method of claim 1, wherein the detecting whether the electric vehicle is in the single pedal control driving mode comprises:

5. The method of claim 4, wherein the detecting whether the electric vehicle satisfies a single pedal control condition comprises:

detecting whether the electric automobile is in a Ready state or not;

6. A drive control device for an electric vehicle, characterized by comprising:

7. The apparatus of claim 6, wherein the first preset threshold and the second preset threshold are both zero.

8. The apparatus of claim 6, further comprising:

9. The apparatus of claim 6, wherein the detection module comprises:

10. An electric vehicle, comprising: the drive control device of the electric vehicle according to any one of claims 6 to 9.