CN115158260B - Automobile braking system and automobile braking method - Google Patents

Automobile braking system and automobile braking method Download PDF

Info

Publication number
CN115158260B
CN115158260B CN202210737172.1A CN202210737172A CN115158260B CN 115158260 B CN115158260 B CN 115158260B CN 202210737172 A CN202210737172 A CN 202210737172A CN 115158260 B CN115158260 B CN 115158260B
Authority
CN
China
Prior art keywords
braking force
braking
wheel
automobile
rear wheel
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN202210737172.1A
Other languages
Chinese (zh)
Other versions
CN115158260A (en
Inventor
石大排
郭俊杰
刘康杰
李士鹏
王正宏
瞿迪
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Hubei University of Arts and Science
Original Assignee
Hubei University of Arts and Science
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Hubei University of Arts and Science filed Critical Hubei University of Arts and Science
Priority to CN202210737172.1A priority Critical patent/CN115158260B/en
Publication of CN115158260A publication Critical patent/CN115158260A/en
Application granted granted Critical
Publication of CN115158260B publication Critical patent/CN115158260B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
    • B60T8/00—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force
    • B60T8/26—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force characterised by producing differential braking between front and rear wheels
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
    • B60T8/00—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force
    • B60T8/17—Using electrical or electronic regulation means to control braking
    • B60T8/1755—Brake regulation specially adapted to control the stability of the vehicle, e.g. taking into account yaw rate or transverse acceleration in a curve
    • B60T8/17557—Brake regulation specially adapted to control the stability of the vehicle, e.g. taking into account yaw rate or transverse acceleration in a curve specially adapted for lane departure prevention
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
    • B60T8/00—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force
    • B60T8/32—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force responsive to a speed condition, e.g. acceleration or deceleration
    • B60T8/321—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force responsive to a speed condition, e.g. acceleration or deceleration deceleration
    • B60T8/322—Systems specially adapted for vehicles driven by more than one axle, e.g. Four Wheel-Drive vehicles
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
    • B60T2270/00—Further aspects of brake control systems not otherwise provided for
    • B60T2270/84—Driver circuits for actuating motor, valve and the like
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T10/00—Road transport of goods or passengers
    • Y02T10/60—Other road transportation technologies with climate change mitigation effect
    • Y02T10/72—Electric energy management in electromobility

Landscapes

  • Engineering & Computer Science (AREA)
  • Transportation (AREA)
  • Mechanical Engineering (AREA)
  • Hydraulic Control Valves For Brake Systems (AREA)
  • Regulating Braking Force (AREA)

Abstract

The invention discloses an automobile braking system and an automobile braking method, wherein the method comprises the following steps: when the braking force of the electric wheels meets preset conditions, the vehicle controller obtains front and rear wheel braking force signals of the vehicle based on the braking parameter signals, the motor controller controls the wheel hub motor to start based on the front and rear wheel braking force signals, the wheel hub motor carries out braking compensation on the front and rear wheel braking force, and the brake controls the vehicle to brake based on the compensated front and rear wheel braking force. Because the braking compensation is carried out on the braking force of the front wheel and the rear wheel through the hub motor, and the automobile is controlled to brake based on the compensated braking force, the problem of insufficient braking force distribution of the front wheel and the rear wheel when the preset condition is met is avoided, compared with the mode that four wheels are adopted for braking simultaneously in the prior art, the braking force distribution of the front wheel is large, the braking force of the rear wheel is small, and traffic accidents caused by the fact that the automobile deviates from an expected track are effectively avoided.

Description

Automobile braking system and automobile braking method
Technical Field
The invention relates to the technical field of automobiles, in particular to an automobile braking system and an automobile braking method.
Background
Nowadays, the investment of automobile research and development in various countries in the world is increased year by year, the development of automobile technology is changed day by day, and the highest running speed of an automobile is also improved rapidly, so that the automobile braking performance is related to the running safety of the automobile to a certain extent.
The existing automobile brake adopts four wheels to brake simultaneously, but the brake force distribution is different, the brake force distributed by the front wheels is larger, the brake force distributed by the rear wheels is smaller, and the automobile is easy to deviate from an expected track due to the fact that the brake force distribution is insufficient, so that traffic accidents are caused.
The foregoing is provided merely for the purpose of facilitating understanding of the technical solutions of the present invention and is not intended to represent an admission that the foregoing is prior art.
Disclosure of Invention
The invention mainly aims to provide an automobile braking system and an automobile braking method, and aims to solve the technical problem that an automobile deviates from an expected track and causes traffic accidents due to insufficient braking force distribution in the prior art.
To achieve the above object, the present invention provides an automotive brake system comprising:
wheel speed sensor, brake, hub motor, inverter, motor controller, brake pedal sensor, whole vehicle controller and battery current sensor;
the brake is respectively connected with the wheel speed sensor and the wheel hub motor, the inverter is respectively connected with the wheel hub motor and the motor controller, the brake controller is respectively connected with the motor controller, the brake pedal sensor and the whole vehicle controller, the battery current sensor is connected with the whole vehicle controller, the brake pedal sensor is arranged on the brake pedal, and the battery current sensor is arranged on the battery;
the whole vehicle controller is used for obtaining front and rear wheel braking force signals of the automobile based on the braking parameter signals when the braking force of the electric wheels meets preset conditions;
the motor controller is used for controlling the wheel hub motor to start based on the front and rear wheel braking force signals;
the wheel hub motor is used for braking and compensating the front and rear wheel braking forces, and judging that the automobile is braked when the compensated front and rear wheel braking forces meet the preset conditions;
the brake is used for controlling the automobile to brake based on the compensated front and rear wheel braking force.
Further, in order to achieve the above object, the present invention also provides an automobile braking method based on the above automobile braking system, the automobile braking method comprising the following steps:
when the braking force of the electric wheels meets preset conditions, the whole vehicle controller obtains braking force signals of front wheels and rear wheels of the automobile based on the braking parameter signals;
the motor controller controls the wheel hub motor to start based on the front and rear wheel braking force signals;
the wheel hub motor carries out braking compensation on the braking force of the front wheel and the rear wheel;
the brake controls the automobile to brake based on the compensated front and rear wheel braking force.
Optionally, before the step of obtaining the front and rear wheel braking force signals of the automobile based on the braking parameter signals when the braking force of the electric wheels meets the preset condition, the whole vehicle controller further includes:
when the brake pedal sensor detects that the brake pedal signal is a preset brake signal, judging that the automobile enters a braking state;
when the automobile enters a braking state, the whole automobile controller acquires a braking parameter signal of the automobile and generates an electric wheel braking force signal of an electric wheel based on the braking parameter signal;
and the brake controls the automobile to brake according to the electric wheel braking force signal.
Optionally, the brake pedal signal includes a brake pedal opening signal and a brake pedal position signal;
correspondingly, when the brake pedal sensor detects that the brake pedal signal is a preset brake signal, the step of judging that the automobile enters a braking state comprises the following steps:
and when the brake pedal sensor detects that the brake pedal opening signal and the brake pedal position signal are preset brake signals, judging that the automobile enters a braking state.
Optionally, the braking parameter signals include an electric wheel speed signal and a battery current signal;
correspondingly, when the automobile enters a braking state, the whole automobile controller acquires a braking parameter signal of the automobile and acquires an electric wheel braking force signal of an electric wheel based on the braking parameter signal, and the method comprises the following steps:
when the automobile enters a braking state, the whole automobile controller acquires the electric wheel speed signal detected by the wheel speed sensor and the battery current signal detected by the battery current sensor;
and the whole vehicle controller obtains an electric wheel braking force signal of the electric wheel based on the electric wheel speed signal and the battery current signal.
Optionally, when the braking force of the electric wheel meets a preset condition, the whole vehicle controller obtains the braking force signals of the front and rear wheels of the vehicle based on the braking parameter signals, including:
when the error of the braking force of the electric wheel and the preset standard braking force exceeds a preset error range, the whole vehicle controller determines the braking force of the front and rear wheels of the automobile based on the wheel speed signal of the electric wheel and the current signal of the battery;
the whole vehicle controller converts the front and rear wheel braking force into front and rear wheel braking force signals.
Optionally, the step of braking compensation of the front and rear wheel braking force by the in-wheel motor includes:
the hub motor determines the actual braking error between the front and rear wheel braking forces and the preset standard braking force;
the in-wheel motor performs braking compensation for the front and rear wheel braking forces based on the actual braking error.
Optionally, the step of braking compensation of the front and rear wheel braking forces by the in-wheel motor based on the actual braking error includes:
the hub motor determines front and rear wheel compensation braking forces based on the actual braking errors;
the in-wheel motor performs brake compensation for the front and rear wheel braking forces based on the front and rear wheel compensation braking forces.
Optionally, after the step of controlling the automobile to brake based on the compensated front and rear wheel braking force, the method further includes:
and when the actual braking errors of the compensated front and rear wheel braking force and the preset standard braking force of the automobile are in the preset error range, the vehicle controller judges that the automobile is braked.
Optionally, after the step of controlling the automobile to brake based on the compensated front and rear wheel braking force, the method further includes:
and returning to the step of braking compensation of the front and rear wheel braking force by the hub motor when the actual braking error between the compensated front and rear wheel braking force of the automobile and the preset standard braking force exceeds the preset error range.
According to the automobile braking system and the automobile braking method, when the braking force of the electric wheels meets the preset conditions, the front and rear wheel braking force signals of the automobile are obtained based on the braking parameter signals, the motor controller controls the wheel hub motor to start based on the front and rear wheel braking force signals, the wheel hub motor carries out braking compensation on the front and rear wheel braking force, the brake controls the automobile to brake based on the compensated front and rear wheel braking force, the problem of insufficient front and rear wheel braking force distribution when the preset conditions are met is avoided, and compared with the mode that four wheels are adopted for braking simultaneously, the front wheel distribution braking force is large, and the rear wheel braking force is small, so that traffic accidents caused by the fact that the automobile deviates from an expected track are effectively avoided.
Drawings
FIG. 1 is a schematic diagram of a brake system for a vehicle according to the present invention;
FIG. 2 is a schematic flow chart of a first embodiment of an automotive braking method based on an automotive braking system according to the present invention;
FIG. 3 is a schematic flow chart of a second embodiment of an automotive braking method based on an automotive braking system according to the present invention;
fig. 4 is a schematic flow chart of a third embodiment of an automobile braking method based on an automobile braking system according to the present invention.
The achievement of the objects, functional features and advantages of the present invention will be further described with reference to the accompanying drawings, in conjunction with the embodiments.
Detailed Description
It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the invention.
The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is apparent that the described embodiments are only some embodiments of the present invention, but not all embodiments, all embodiments obtained by persons skilled in the art based on the embodiments in the present invention without making creative efforts, belong to the protection scope of the present invention.
It should be noted that the descriptions of "first," "second," etc. in the embodiments of the present invention are for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include at least one such feature. In addition, the technical solutions of the embodiments may be combined with each other, but it is necessary to base that the technical solutions can be realized by those skilled in the art, and when the technical solutions are contradictory or cannot be realized, the combination of the technical solutions should be considered to be absent and not within the scope of protection claimed in the present invention.
Referring to fig. 1, fig. 1 is a schematic structural diagram of an automotive braking system according to the present invention.
As shown in fig. 1, the automobile brake system proposed by the present invention includes: wheel speed sensor, stopper, in-wheel motor, dc-to-ac converter, motor controller, brake pedal sensor, whole car controller and battery current sensor.
It should be noted that, the stopper respectively with wheel speed sensor with in-wheel motor is connected, the dc-to-ac converter respectively with in-wheel motor with motor controller is connected, brake controller respectively with motor controller brake pedal sensor and whole car controller are connected, battery current sensor with whole car controller is connected, brake pedal sensor sets up on the brake pedal, battery current sensor sets up on the battery.
And the whole vehicle controller is used for obtaining front and rear wheel braking force signals of the automobile based on the braking parameter signals when the braking force of the electric wheels meets preset conditions.
It is noted that the electric wheel braking force may be a force required when the wheel speed of the electric wheel is reduced to zero and the electric wheel does not slip. The electric wheel braking force can be controlled by a brake and a motor controller, so that the electric wheel braking force can be composed of the motor braking force and the brake braking force.
It is understood that the preset condition may be a condition preset in the whole vehicle controller for judging when the vehicle enters abnormal braking. The preset condition may be determined by a technician according to the braking force of the electric wheel in an ideal braking state. In the actual braking process, the electric wheel braking force has errors with the electric wheel braking force in an ideal state, if the errors do not exceed the standard error threshold value, the electric wheel braking force can safely finish braking, otherwise, if the errors exceed the standard error threshold value, the problem that the electric wheel braking force is insufficient in braking force distribution on front and rear wheels at the moment can be judged, and potential safety hazards exist in the braking process at the moment.
It should be noted that, the abnormal braking may include a sideslip phenomenon, and a braking corresponding to a slipping phenomenon occurring when parking on a slope due to an insufficient braking force distribution.
It is understood that the brake parameter signal may be a parameter signal related to braking force detected by a sensor, such as wheel speed, power, wheel radius, etc.
The braking force of the front and the rear wheels is determined by the braking parameters and then is converted into an electric signal form to be transmitted in the automobile braking system, wherein the electric signal is the braking force signal of the front and the rear wheels.
In the specific implementation, the front wheels are braked firstly, the rear wheels are not braked, the electric wheel braking force is equal to the front wheel braking force at the moment, when the error of the front wheel braking force and the electric wheel braking force in an ideal braking state exceeds a preset error range, the whole vehicle controller determines the front and rear wheel braking forces based on the braking parameters, and converts the front and rear wheel braking forces into front and rear wheel braking force signals to be transmitted to the hub motor so that the hub motor compensates the front and rear wheel braking forces.
The motor controller is used for controlling the wheel hub motor to start based on the front and rear wheel braking force signals.
The motor controller in the system may be a controller that controls the motor of the electric wheel when receiving the control signal, and the front and rear wheel braking force signal may be a control signal of the motor controller.
In the specific implementation, when the whole vehicle controller transmits the obtained front and rear wheel braking force signals to the motor controller, the motor controller can control the wheel hub motor to start based on the front and rear wheel braking force signals.
The hub motor is used for braking compensation of the braking force of the front wheel and the rear wheel.
It should be noted that, in the system, the hub motor can be a motor for braking compensation of braking force of the automobile and is controlled by a motor controller.
In the specific implementation, when the whole vehicle controller detects that the braking force of the electric wheel meets the preset condition, the front and rear wheel braking force signals are transmitted to the motor controller, so that the motor controller controls the wheel hub motor to start based on the front and rear wheel braking force signals, and the wheel hub motor is enabled to perform braking compensation.
The brake is used for controlling the automobile to brake based on the compensated front and rear wheel braking force.
In the compensating braking process, the brake can brake based on the compensated front and rear wheel braking force, and when the front and rear wheel braking force compensation is completed and the preset condition is met, the brake can be judged to be capable of safely completing the braking of the automobile.
According to the automobile braking system, when the braking force of the electric wheels meets the preset conditions, the front and rear wheel braking force signals of the automobile are obtained based on the braking parameter signals, the motor controller controls the wheel hub motor to start based on the front and rear wheel braking force signals, the wheel hub motor carries out braking compensation on the front and rear wheel braking force, and the brake controls the automobile to brake based on the compensated front and rear wheel braking force, so that the problem of insufficient front and rear wheel braking force distribution when the preset conditions are met is avoided.
Based on the above-mentioned automobile brake system, a first embodiment of the automobile brake method of the present invention is presented.
Referring to fig. 2, fig. 2 is a schematic flow chart of a first embodiment of the braking method of the present invention.
In this embodiment, the automobile braking method includes the following steps:
step S10: and when the braking force of the electric wheels meets the preset conditions, the vehicle controller obtains braking force signals of front wheels and rear wheels of the vehicle based on the braking parameter signals.
The braking force of the electric wheel may be a force required when the wheel speed of the electric wheel is reduced to zero and the electric wheel does not slip. The electric wheel braking force can be controlled by a brake and a motor controller, so that the electric wheel braking force can be composed of the motor braking force and the brake braking force.
It is understood that the preset condition may be a condition preset in the whole vehicle controller for judging when the vehicle enters abnormal braking. The preset condition may be determined by a technician according to the braking force of the electric wheel in an ideal braking state. In the actual braking process, the electric wheel braking force has errors with the electric wheel braking force in an ideal state, if the errors do not exceed the standard error threshold value, the electric wheel braking force can safely finish braking, otherwise, if the errors exceed the standard error threshold value, the problem that the electric wheel braking force is insufficient in braking force distribution on front and rear wheels at the moment can be judged, and potential safety hazards exist in the braking process at the moment.
It should be noted that, the abnormal braking may include a sideslip phenomenon, and a braking corresponding to a slipping phenomenon occurring when parking on a slope due to an insufficient braking force distribution.
It is understood that the brake parameter signal may be a parameter signal related to braking force detected by a sensor, such as wheel speed, power, wheel radius, etc.
The braking force of the front and the rear wheels is determined by the braking parameters and then is converted into an electric signal form to be transmitted in the automobile braking system, wherein the electric signal is the braking force signal of the front and the rear wheels.
In the specific implementation, the front wheels are braked firstly, the rear wheels are not braked, the electric wheel braking force is equal to the front wheel braking force at the moment, when the error of the front wheel braking force and the electric wheel braking force in an ideal braking state exceeds a preset error range, the whole vehicle controller determines the front and rear wheel braking forces based on the braking parameters, and converts the front and rear wheel braking forces into front and rear wheel braking force signals to be transmitted to the hub motor so that the hub motor compensates the front and rear wheel braking forces.
Further, in order to make the vehicle controller more timely determine whether the driving force of the electric wheel meets the preset condition, the response time of the vehicle controller to abnormal braking is improved, in this embodiment, step S10 may include:
step S11: and when the error of the braking force of the electric wheel and the preset standard braking force exceeds a preset error range, the vehicle controller determines the braking force of the front and rear wheels of the vehicle based on the wheel speed signal of the electric wheel and the current signal of the battery.
It should be noted that the preset standard braking force may be determined by a technician according to an ideal braking force curve drawn by the front wheel braking force and the rear wheel braking force in an ideal state, that is, a point on the curve is the preset standard braking force.
It is understood that the preset error range is the maximum error range between the actual braking force and the ideal braking force, and exceeding the range indicates that there is a safety hazard in the braking process. The front and rear wheel braking forces in the actual braking process cannot completely conform to an ideal braking force curve generally, and when the errors of the front and rear wheel braking forces and the ideal braking force curve do not exceed a preset error range, the automobile braking can be safely completed, otherwise, the problem that the electric wheel braking force is insufficient in front and rear wheel distribution is indicated, a certain potential safety hazard exists, accordingly, when the errors of the front wheel braking forces and the ideal braking force curve exceed the preset error range, the front wheel braking force distribution is insufficient, and when the errors of the rear wheel braking forces and the ideal braking force curve exceed the preset error range, the rear wheel braking force distribution is insufficient.
The ideal braking force curve can ensure that the front and rear wheels are locked simultaneously in the braking process, namely, the braking forces of the front and rear wheels are respectively equal to the respective adhesive force, so that the ideal braking force curve can be determined according to the following formula:
wherein m is the mass of the whole vehicle, g is the gravitational acceleration, h g Is the height of the mass center, b is the distance from the rear axle to the mass center, L is the wheelbase between the front axle and the rear axle, F u1 For front wheel braking force, F u2 Is the braking force of the rear wheels.
The electric wheel speed signal may be obtained by a wheel speed sensor, the electric wheel speed signal may include a wheel speed of the electric wheel, and the battery current signal may be obtained by a battery current sensor, the battery current signal including a current of the battery.
In the specific implementation, when the error of the electric wheel braking force and the preset standard braking force does not exceed the preset error range, the front wheels are completely braked, the rear wheels are not braked, the electric wheel braking force at the moment is equal to the front wheel braking force, when the error of the front wheel braking force and the preset standard braking force exceeds the preset error range, the electric wheel braking force is indicated to be insufficient in distribution, the braking force is required to be distributed for the rear wheels to carry out auxiliary braking, and the whole vehicle controller acquires related parameters (such as parameters of wheel speed, battery current, braking intensity and the like) through the wheel speed sensor and the battery current sensor to be used for redistributing the braking force of the front wheels and the rear wheels.
It will be appreciated that the braking force of the front and rear wheels of a vehicle can be determined as follows:
wherein m is the mass of the whole vehicleG is gravity acceleration, h g Is the height of the mass center, z is the braking strength, L is the wheelbase between the front axle and the rear axle, F u1 For front wheel braking force, F u2 For the braking force of the rear wheels,is the adhesion coefficient between the wheel and the ground.
It will be appreciated that the brake strength can be determined as follows:
where z is the brake strength and a is the maximum braking deceleration at which the wheel is not locked.
It will be appreciated that the adhesion coefficient between the wheel and the ground can be determined as follows:
wherein,l is the wheel base between the front axle and the rear axle, b is the distance from the rear axle to the mass center, h is the attachment coefficient between the wheel and the ground g And the beta braking force distribution coefficient is the height of the mass center.
It will be appreciated that the brake force distribution coefficient may be determined as follows:
wherein, beta braking force distribution coefficient, F u1 For front wheel braking force, F u2 Is the braking force of the rear wheels.
In order to ensure the braking stability and braking efficiency of the electric-wheel vehicle, the adhesion coefficient is calculated when the braking forces of the front and rear wheels are calculatedShould satisfy->At the same time the braking strength z should be satisfied
Step S12: the whole vehicle controller converts the front and rear wheel braking force into front and rear wheel braking force signals.
The front and rear wheel braking force signals may be electric signals obtained by converting electric signals of the front and rear wheel braking forces after determining the front and rear wheel braking forces for the vehicle controller.
In specific implementation, the vehicle controller obtains relevant braking parameters based on the sensors, determines the braking force of the front wheels and the rear wheels, and then transmits the braking force of the front wheels and the rear wheels to the motor controller in the form of electric signals.
It should be understood that, the whole vehicle controller of the embodiment can make the whole vehicle controller make a quick response when the electric wheel braking force is not distributed enough through the preset standard braking force under the ideal braking force curve so as to distribute the electric wheel braking force again, thereby effectively improving the safety of the automobile during braking.
Step S20: the motor controller controls the in-wheel motor to start based on the front and rear wheel braking force signals.
In this embodiment, the motor controller may be a controller that controls the motor of the electric wheel when receiving the control signal, and the front-rear wheel braking force signal may be a control signal of the motor controller.
In the specific implementation, when the whole vehicle controller transmits the obtained front and rear wheel braking force signals to the motor controller, the motor controller can control the wheel hub motor to start based on the front and rear wheel braking force signals.
Step S30: and the hub motor carries out braking compensation on the braking force of the front wheel and the rear wheel.
It should be noted that, in this embodiment, the in-wheel motor may be a motor for performing braking compensation on braking force of the automobile, and is controlled by a motor controller.
In the specific implementation, when the whole vehicle controller detects that the braking force of the electric wheel meets the preset condition, the front and rear wheel braking force signals are transmitted to the motor controller, so that the motor controller controls the wheel hub motor to start based on the front and rear wheel braking force signals, and the wheel hub motor is enabled to perform braking compensation.
Further, in order to improve the accuracy of the brake compensation, in this embodiment, the step S30 may include:
step S31: the hub motor determines an actual braking error between the front and rear wheel braking forces and the preset standard braking force.
In the specific implementation, when the hub motor is started, the magnitude of the braking force of the front wheels and the rear wheels can be obtained through the whole vehicle controller, and the actual braking errors between the braking force of the front wheels and the braking force of the rear wheels and the preset standard braking force under an ideal braking force curve are determined.
Step S32: the in-wheel motor performs braking compensation for the front and rear wheel braking forces based on the actual braking error.
In a specific implementation, after the actual braking error is determined, the hub motor can perform braking compensation on the front and rear wheel braking forces according to the actual braking error, so that the front and rear wheel braking forces conform to an ideal braking force curve.
It should be understood that in this embodiment, the actual braking error between the braking force of the front wheel and the braking force of the rear wheel and the preset standard braking force is determined by the hub motor, the braking compensation force of the front wheel and the braking compensation force of the rear wheel is determined by the actual braking error, and the braking compensation is performed by the braking compensation force of the front wheel and the braking compensation force of the rear wheel, so that the accuracy of the braking compensation is effectively improved.
Further, in order to improve the effect of braking compensation, in this embodiment, step S32 may include:
step S321, the in-wheel motor determines front and rear wheel compensation braking forces based on the actual braking errors.
It should be noted that the front and rear wheel compensation braking force may be determined by a preset standard braking force under the curve of the actual braking error and the ideal braking force.
In step S322, the in-wheel motor performs brake compensation for the front and rear wheel braking forces based on the front and rear wheel compensation braking forces.
In particular implementation, the hub motor can determine the braking force to be compensated, namely the braking compensation force of the front and rear wheels according to the ideal braking force curve based on the actual braking error, and perform braking compensation on the braking force of the front and rear wheels according to the braking force of the front and rear wheels, so that the braking compensation effect is effectively improved.
Step S40: the brake controls the automobile to brake based on the compensated front and rear wheel braking force.
In the compensating braking process, the brake can brake based on the compensated front and rear wheel braking force, and when the front and rear wheel braking force compensation is completed and the preset condition is met, the brake can be judged to be capable of safely completing the braking of the automobile.
According to the embodiment, when the braking force of the electric wheels meets the preset conditions, the front and rear wheel braking force signals of the automobile are obtained based on the braking parameter signals, the motor controller controls the wheel hub motor to start based on the front and rear wheel braking force signals, the wheel hub motor carries out braking compensation on the front and rear wheel braking force, and the brake controls the automobile to brake based on the compensated front and rear wheel braking force, so that the problem of insufficient front and rear wheel braking force distribution when the preset conditions are met is avoided.
Referring to fig. 3, fig. 3 is a flowchart illustrating a second embodiment of the braking method of the present invention.
Based on the above-mentioned first embodiment, in order to improve the braking capability of the vehicle brake, in this embodiment, before step S10, the method further includes:
step S01: and when the brake pedal sensor detects that the brake pedal signal is a preset brake signal, judging that the automobile enters a braking state.
The brake pedal sensor is disposed on the brake pedal and can be used for detecting the current state information (such as the state information of the brake pedal position, the opening degree, the stress and the like) of the brake pedal, and converting the current state information into a brake pedal signal. Accordingly, the brake pedal signal may include an electrical signal such as a position signal, an opening signal, and a force signal of the brake pedal.
It is understood that the preset brake signal may be a signal corresponding to a brake pedal when the vehicle enters a braking state.
In a specific implementation, when the brake pedal is stepped on, the brake pedal sensor can detect a brake pedal opening signal and a brake pedal position signal and transmit the signals to the whole vehicle controller, the whole vehicle controller can judge the brake pedal signal based on a preset brake signal, and if the brake pedal signal is consistent with the preset brake signal, the automobile can be judged to enter a braking state at the moment.
It should be appreciated that if the brake pedal signal is inconsistent with the predetermined brake signal, it may be determined that the vehicle is not in a braked condition.
Step S02: and when the automobile enters a braking state, the whole automobile controller acquires a braking parameter signal of the automobile and generates an electric wheel braking force signal of the electric wheel based on the braking parameter signal.
It should be noted that the braking parameter signal may include an electric wheel speed signal and a battery current signal, where the electric wheel speed signal may be detected by a wheel speed sensor, and the battery current signal may be detected by a battery current sensor.
It is understood that when the vehicle has not entered brake compensation, the vehicle brakes are controlled by the motor controller to brake and the front wheels are braked individually, and the electric wheel braking force is equal to the sum of the front wheel braking force and the motor braking force.
It should be noted that, the driving force of the electric wheel may be determined according to the following formula based on the parameters in the braking parameter signal:
wherein F is t Is an electric wheel drivePower, T e For rated torque of motor, P e The motor rated output power is given, n is the rotating speed, and r is the wheel radius.
In the specific implementation, when the vehicle controller judges that the vehicle enters a braking state, the wheel speed sensor and the battery current sensor can acquire corresponding signals such as the wheel speed of the electric wheel and the battery current to determine the braking force of the electric wheel, and the braking force of the electric wheel is converted into a braking force signal of the electric wheel and is transmitted to the brake.
Step S03: and the brake controls the automobile to brake according to the electric wheel braking force signal.
In a specific implementation, when the automobile does not enter brake compensation, the brake can control the front wheel to brake according to the electric wheel braking force signal so as to realize the braking of the automobile.
When the automobile enters a braking state, the electric wheel speed sensor and the battery current sensor acquire braking parameter signals to determine electric wheel braking force signals, and the brake brakes the automobile by the electric wheel braking force, so that the braking capability of the automobile is effectively improved.
Referring to fig. 4, fig. 4 is a schematic flow chart of a third embodiment of the braking method of the present invention.
Based on the first embodiment, in order to improve the working efficiency of the in-wheel motor, in this embodiment, after the step S40, the method further includes:
step S50: and when the actual braking errors of the compensated front and rear wheel braking force and the preset standard braking force of the automobile are in the preset error range, the vehicle controller judges that the automobile is braked.
The preset standard braking force is the braking force when the front and rear wheels are locked simultaneously, so when the compensated front and rear wheel braking force reaches the preset standard braking force, the front and rear wheels are locked, the situation is ideal in the actual braking process, and the situation is generally difficult to achieve, so long as the error between the front and rear wheel braking force and the preset standard braking force is smaller than a certain range, namely, the front and rear wheels can be considered to be locked when the error is in the preset error range, and potential safety hazards in the braking process can be ignored at the moment.
In the specific implementation, the whole vehicle controller can judge the compensated front and rear wheel braking force in real time, and when the actual braking error between the compensated front and rear wheel braking force and the preset standard braking force is in the preset error range, the front and rear wheels of the vehicle can be judged to be approximately locked, the vehicle is braked, and the hub motor is controlled to stop working.
Step S50': and returning to the step of braking compensation of the front and rear wheel braking force by the hub motor when the actual braking error between the compensated front and rear wheel braking force of the automobile and the preset standard braking force exceeds the preset error range.
In specific implementation, when the actual braking error between the front and rear wheels of the compensated automobile and the preset standard braking force exceeds the preset error range, the whole automobile controller indicates that the braking force compensation is insufficient, and the braking compensation is needed to be continued, the step of the wheel hub motor for braking compensation of the front and rear wheel braking force is returned to, so that the wheel hub motor can continue to brake compensation of the front and rear wheel braking force.
According to the embodiment, the actual error between the front and rear wheel braking force and the preset standard braking force of the automobile is judged through the whole automobile controller, when the actual error is in the preset error range, the completion of compensation is judged, the wheel hub motor is controlled to stop working, the problem that the wheel hub motor still works after the completion of compensation, unnecessary machine loss is caused, and the working efficiency of the motor is effectively improved.
It should be noted that, in this document, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or system that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or system. Without further limitation, an element defined by the phrase "comprising one … …" does not exclude the presence of other like elements in a process, method, article, or system that comprises the element.
The foregoing embodiment numbers of the present invention are merely for the purpose of description, and do not represent the advantages or disadvantages of the embodiments.
From the above description of the embodiments, it will be clear to those skilled in the art that the above-described embodiment method may be implemented by means of software plus a necessary general hardware platform, but of course may also be implemented by means of hardware, but in many cases the former is a preferred embodiment. Based on such understanding, the technical solution of the present invention may be embodied essentially or in a part contributing to the prior art in the form of a software product stored in a storage medium (e.g. read-only memory/random-access memory, magnetic disk, optical disk), comprising instructions for causing a terminal device (which may be a mobile phone, a computer, a server, an air conditioner, or a network device, etc.) to perform the method according to the embodiments of the present invention.
The foregoing description is only of the preferred embodiments of the present invention, and is not intended to limit the scope of the invention, but rather is intended to cover any equivalents of the structures or equivalent processes disclosed herein or in the alternative, which may be employed directly or indirectly in other related arts.

Claims (2)

1. An automotive braking system, the automotive braking system comprising:
wheel speed sensor, brake, hub motor, inverter, motor controller, brake pedal sensor, whole vehicle controller and battery current sensor;
the brake is respectively connected with the wheel speed sensor and the wheel hub motor, the inverter is respectively connected with the wheel hub motor and the motor controller, the brake controller is respectively connected with the motor controller, the brake pedal sensor and the whole vehicle controller, the battery current sensor is connected with the whole vehicle controller, the brake pedal sensor is arranged on the brake pedal, and the battery current sensor is arranged on the battery;
the whole vehicle controller is used for obtaining front and rear wheel braking force signals of the automobile based on the braking parameter signals when the braking force of the electric wheels meets preset conditions;
the motor controller is used for controlling the wheel hub motor to start based on the front and rear wheel braking force signals;
the hub motor is used for braking and compensating the braking force of the front wheel and the rear wheel;
the brake is used for controlling the automobile to brake based on the compensated braking force of the front and rear wheels;
the electric wheel braking force comprises a front wheel braking force and a rear wheel braking force, the braking parameter signals comprise an electric wheel speed signal and a battery current signal, and the front and rear wheel braking force signals comprise a front wheel braking force signal and a rear wheel braking force signal;
the vehicle controller is further configured to determine that the front wheel braking force is not sufficiently distributed when an error between the front wheel braking force and a preset standard braking force exceeds a preset error range;
the vehicle controller is further configured to determine, when the front wheel braking force distribution is insufficient, the front wheel braking force signal and the rear wheel braking force signal of the vehicle based on the electric wheel speed signal and the battery current signal, so as to enable rear wheel auxiliary front wheel braking of the vehicle;
the vehicle controller is further configured to brake by the front wheel when an error between the front wheel braking force and the preset standard braking force does not exceed the preset error range;
the vehicle controller is further configured to determine that the vehicle completes compensation when an actual braking error between the compensated front and rear wheel braking forces of the vehicle and the preset standard braking force is within the preset error range;
the vehicle controller is further configured to keep the hub motor started until the actual braking error is within the preset error range when the actual braking error between the compensated front and rear wheel braking forces of the vehicle and the preset standard braking force is not within the preset error range;
the brake pedal signals comprise brake pedal opening signals and brake pedal position signals, and the brake parameter signals comprise electric wheel speed signals and battery current signals;
the brake pedal sensor is further used for judging that the automobile enters a braking state when detecting that the brake pedal opening signal and the brake pedal position signal are preset braking signals;
the whole vehicle controller is further used for acquiring the electric wheel speed signal detected by the wheel speed sensor and the battery current signal detected by the battery current sensor when the automobile enters a braking state;
the whole vehicle controller is further used for obtaining an electric wheel braking force signal of the electric wheel based on the electric wheel speed signal and the battery current signal;
the brake is also used for controlling the automobile to brake according to the electric wheel braking force signal;
the hub motor is also used for determining the actual braking error between the braking force of the front wheel and the braking force of the rear wheel and the preset standard braking force;
the hub motor is further used for determining front and rear wheel compensation braking forces based on the actual braking errors and performing braking compensation on the front and rear wheel braking forces based on the front and rear wheel compensation braking forces.
2. An automobile braking method based on the automobile braking system according to claim 1, characterized in that it comprises the following steps:
when the braking force of the electric wheels meets preset conditions, the whole vehicle controller obtains braking force signals of front wheels and rear wheels of the automobile based on the braking parameter signals;
the motor controller controls the wheel hub motor to start based on the front and rear wheel braking force signals;
the wheel hub motor carries out braking compensation on the braking force of the front wheel and the rear wheel;
the brake controls the automobile to brake based on the compensated braking force of the front wheel and the rear wheel;
the electric wheel braking force comprises a front wheel braking force and a rear wheel braking force, the braking parameter signals comprise an electric wheel speed signal and a battery current signal, and the front and rear wheel braking force signals comprise a front wheel braking force signal and a rear wheel braking force signal;
when the braking force of the electric wheels meets the preset condition, the whole vehicle controller obtains the braking force signals of the front wheels and the rear wheels of the automobile based on the braking parameter signals, and the method comprises the following steps:
when the error between the front wheel braking force and the preset standard braking force exceeds a preset error range, the whole vehicle controller judges that the front wheel braking force is not distributed enough;
when the front wheel braking force distribution is insufficient, the whole vehicle controller determines the front wheel braking force signal and the rear wheel braking force signal of the automobile based on the electric wheel speed signal and the battery current signal so as to enable the rear wheel auxiliary front wheel braking of the automobile;
when the error between the front wheel braking force and the preset standard braking force exceeds the preset error range, the whole vehicle controller further comprises the following components before the step of judging that the front wheel braking force is not distributed enough:
the whole vehicle controller brakes through the front wheels when the error between the front wheel braking force and the preset standard braking force does not exceed the preset error range;
after the step of controlling the automobile to brake based on the compensated front and rear wheel braking force, the brake further comprises the following steps:
when the actual braking errors of the front and rear wheel braking force and the preset standard braking force of the automobile after compensation are within the preset error range, the whole automobile controller judges that the automobile is compensated;
when the actual braking error between the compensated front and rear wheel braking force of the automobile and the preset standard braking force exceeds the preset error range, the whole automobile controller returns to the step of braking compensation of the front and rear wheel braking force by the hub motor until the actual braking error is in the preset error range;
the brake pedal signals comprise brake pedal opening signals and brake pedal position signals, and the brake parameter signals comprise electric wheel speed signals and battery current signals;
when the braking force of the electric wheels meets the preset condition, the whole vehicle controller further comprises the following components before the step of obtaining the braking force signals of the front wheels and the rear wheels of the automobile based on the braking parameter signals:
when the brake pedal sensor detects that the brake pedal opening signal and the brake pedal position signal are preset brake signals, judging that the automobile enters a brake state;
when the automobile enters a braking state, the whole automobile controller acquires the electric wheel speed signal detected by the wheel speed sensor and the battery current signal detected by the battery current sensor;
the whole vehicle controller obtains an electric wheel braking force signal of the electric wheel based on the electric wheel speed signal and the battery current signal;
the brake controls the automobile to brake according to the electric wheel braking force signal;
the step of braking compensation of the front and rear wheel braking force by the hub motor comprises the following steps:
the hub motor determines the actual braking error between the front and rear wheel braking forces and the preset standard braking force;
the in-wheel motor determines front and rear wheel compensation braking forces based on the actual braking errors, and performs braking compensation on the front and rear wheel braking forces based on the front and rear wheel compensation braking forces.
CN202210737172.1A 2022-06-27 2022-06-27 Automobile braking system and automobile braking method Active CN115158260B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202210737172.1A CN115158260B (en) 2022-06-27 2022-06-27 Automobile braking system and automobile braking method

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202210737172.1A CN115158260B (en) 2022-06-27 2022-06-27 Automobile braking system and automobile braking method

Publications (2)

Publication Number Publication Date
CN115158260A CN115158260A (en) 2022-10-11
CN115158260B true CN115158260B (en) 2024-01-23

Family

ID=83487338

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202210737172.1A Active CN115158260B (en) 2022-06-27 2022-06-27 Automobile braking system and automobile braking method

Country Status (1)

Country Link
CN (1) CN115158260B (en)

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2006021745A (en) * 2004-06-11 2006-01-26 Advics:Kk Brake device for vehicle and brake control program for vehicle
CN102269658A (en) * 2011-04-29 2011-12-07 北京工业大学 Electro-hydraulic combined brake experiment vehicle
CN103332184A (en) * 2013-06-08 2013-10-02 北京航空航天大学 Electric-hydro complex brake control method for electric vehicle use and controlling device thereof
CN106427601A (en) * 2015-08-11 2017-02-22 比亚迪股份有限公司 Braking system and baking method based on four-wheel-drive for electric vehicle, as well as electric vehicle
CN109278566A (en) * 2018-10-15 2019-01-29 陕西汽车集团有限责任公司 Rear wheel drive pure electric vehicle Brake energy recovery control method and device
CN110001609A (en) * 2019-04-23 2019-07-12 岭南师范学院 A kind of four-wheel wheel hub driving electric car line traffic control electric braking control device
CN113602098A (en) * 2021-09-16 2021-11-05 九江职业技术学院 Electric automobile electro-hydraulic composite braking system based on hub motor driving and front and rear axle braking force distribution method
CN113954796A (en) * 2021-11-16 2022-01-21 南京航空航天大学 Electric-hydraulic composite braking torque fluctuation coordination control system and method for electric automobile
CN114590131A (en) * 2022-01-21 2022-06-07 北方工业大学 Braking energy recovery control method and device and vehicle

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2006021745A (en) * 2004-06-11 2006-01-26 Advics:Kk Brake device for vehicle and brake control program for vehicle
CN102269658A (en) * 2011-04-29 2011-12-07 北京工业大学 Electro-hydraulic combined brake experiment vehicle
CN103332184A (en) * 2013-06-08 2013-10-02 北京航空航天大学 Electric-hydro complex brake control method for electric vehicle use and controlling device thereof
CN106427601A (en) * 2015-08-11 2017-02-22 比亚迪股份有限公司 Braking system and baking method based on four-wheel-drive for electric vehicle, as well as electric vehicle
CN109278566A (en) * 2018-10-15 2019-01-29 陕西汽车集团有限责任公司 Rear wheel drive pure electric vehicle Brake energy recovery control method and device
CN110001609A (en) * 2019-04-23 2019-07-12 岭南师范学院 A kind of four-wheel wheel hub driving electric car line traffic control electric braking control device
CN113602098A (en) * 2021-09-16 2021-11-05 九江职业技术学院 Electric automobile electro-hydraulic composite braking system based on hub motor driving and front and rear axle braking force distribution method
CN113954796A (en) * 2021-11-16 2022-01-21 南京航空航天大学 Electric-hydraulic composite braking torque fluctuation coordination control system and method for electric automobile
CN114590131A (en) * 2022-01-21 2022-06-07 北方工业大学 Braking energy recovery control method and device and vehicle

Also Published As

Publication number Publication date
CN115158260A (en) 2022-10-11

Similar Documents

Publication Publication Date Title
US20170096070A1 (en) Method for controlling braking of regenerative braking co-operative control system for vehicle
CN107009914B (en) Auxiliary braking system and control method of electric automobile and electric automobile
CN106945665B (en) A kind of car ramp starting anti-slip control method and control system
JPH07111707A (en) Brake power controller for electric automobile
CN111469674A (en) Braking energy recovery control method for new energy cargo vehicle
CN101905659A (en) Regenerative brake control system and method
US11325573B2 (en) Rear wheel regenerative braking control system for vehicle and method therefor
CN102442310B (en) Method and driveline stability control system for a vehicle
CN112776809B (en) Driver hill start assisting method, device, equipment and storage medium
CN111959285A (en) Electric vehicle energy recovery method, equipment, storage medium and device
CN107161271A (en) Moped Scooter based on acceleration detection brakes anti-skidding method
CN114475260B (en) Energy recovery method and device, electric automobile and storage medium
CN112622641A (en) Vehicle control method, device and system
CN109367534B (en) Electronic parking control method and device
CN115158260B (en) Automobile braking system and automobile braking method
CN114274790A (en) Power distribution method and system of pure electric vehicle, readable storage medium and vehicle
US20230398876A1 (en) System for controlling regenerative braking torque of eco-friendly vehicle and method of controlling same
CN111332127A (en) Automobile braking energy recovery method
CN116552252A (en) Kinetic energy recovery control system
CN112810612B (en) Automobile accelerator acceleration control method, device, equipment and storage medium
CN111645527B (en) Electric vehicle braking energy recovery control method
CN113815621A (en) Gradient calculation method and device, vehicle and computer-readable storage medium
US6893380B2 (en) Traction control system including converter protection function
CN114179621A (en) Steep-slope slow-descending control method and device for vehicle
CN112810613A (en) Starting energy consumption optimization method, device, equipment and storage medium

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant