CN111251898A - Control method and device of composite braking system and electric automobile - Google Patents

Control method and device of composite braking system and electric automobile Download PDF

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Publication number
CN111251898A
CN111251898A CN201811459297.2A CN201811459297A CN111251898A CN 111251898 A CN111251898 A CN 111251898A CN 201811459297 A CN201811459297 A CN 201811459297A CN 111251898 A CN111251898 A CN 111251898A
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China
Prior art keywords
braking torque
brake
braking
regenerative
torque
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CN201811459297.2A
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Chinese (zh)
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吕海军
廖银生
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BYD Co Ltd
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BYD Co Ltd
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Priority to CN201811459297.2A priority Critical patent/CN111251898A/en
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
    • B60L15/00—Methods, circuits, or devices for controlling the traction-motor speed of electrically-propelled vehicles
    • B60L15/20—Methods, circuits, or devices for controlling the traction-motor speed of electrically-propelled vehicles for control of the vehicle or its driving motor to achieve a desired performance, e.g. speed, torque, programmed variation of speed
    • B60L15/2009—Methods, circuits, or devices for controlling the traction-motor speed of electrically-propelled vehicles for control of the vehicle or its driving motor to achieve a desired performance, e.g. speed, torque, programmed variation of speed for braking
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
    • B60L7/00—Electrodynamic brake systems for vehicles in general
    • B60L7/10—Dynamic electric regenerative braking
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
    • B60L2240/00—Control parameters of input or output; Target parameters
    • B60L2240/40—Drive Train control parameters
    • B60L2240/42—Drive Train control parameters related to electric machines
    • B60L2240/423—Torque
    • 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

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Transportation (AREA)
  • Mechanical Engineering (AREA)
  • Electric Propulsion And Braking For Vehicles (AREA)
  • Regulating Braking Force (AREA)

Abstract

The application provides a control method and a control device of a composite braking system and an electric automobile, wherein the composite braking system comprises an electromechanical braking system and a regenerative braking system, the electromechanical braking system is used for forming a basic braking torque, the regenerative braking system is used for forming a regenerative braking torque, and the control method comprises the following steps: acquiring a braking signal, and calculating a required braking torque according to the braking signal; distributing basic braking torque and regenerative braking torque according to the required braking torque and the current working condition; and controlling the electromechanical braking system to form a basic braking torque, and controlling the regenerative braking system to form a regenerative braking torque. The system can fully utilize the regenerative braking system to recover energy in the full working condition range of the electric automobile, and the endurance mileage of the electric automobile is improved.

Description

Control method and device of composite braking system and electric automobile
Technical Field
The application relates to the technical field of vehicle control, in particular to a control method and device of a composite braking system and an electric automobile.
Background
In the prior art, an electric vehicle is mainly braked by an Electromechanical Brake System (EMB), and the regenerative braking characteristic of a power motor is not fully utilized, so that energy cannot be effectively recovered during braking, and energy consumption is wasted.
Disclosure of Invention
The application provides a control method and device of a composite braking system and an electric automobile, so that a cooperative braking function of a regenerative braking system and an electromechanical braking system is provided for the electric automobile, the regenerative braking system is fully utilized to recover energy in the full working condition range of the electric automobile, the endurance mileage of the electric automobile is improved, and the stability and reliability of the composite braking system are improved. In addition, because a hydraulic brake system is not used, mechanical connection can be reduced, hydraulic brake pipelines can be removed, the quality of the whole automobile can be effectively reduced, the size of the electric automobile is reduced, and the difficulty of arrangement and assembly is reduced. In addition, a hydraulic brake system is not needed, so that the brake fluid does not need to be replaced, and the condition that the brake fluid leaks to cause environmental pollution can be avoided.
An embodiment of an aspect of the present application provides a control method for a composite brake system, where the composite brake system includes an electromechanical brake system and a regenerative brake system, the electromechanical brake system is configured to form a basic braking torque, the regenerative brake system is configured to form a regenerative braking torque, and the control of the composite brake system includes:
obtaining a braking signal, and calculating a required braking torque according to the braking signal;
distributing the basic braking torque and the regenerative braking torque according to the required braking torque and the current working condition;
and controlling the electromechanical braking system to form the basic braking torque, and controlling the regenerative braking system to form the regenerative braking torque.
According to the control method of the composite braking system, the composite braking system comprises the electromechanical braking system and the regenerative braking system, so that the stability and the reliability of the system can be improved under a failure mode. The method comprises the steps of obtaining a braking signal, calculating a required braking torque according to the braking signal, distributing a basic braking torque and a regenerative braking torque according to the required braking torque and the current working condition, and finally controlling an electromechanical braking system to form the basic braking torque and controlling the regenerative braking system to form the regenerative braking torque. Therefore, the cooperative braking function of the regenerative braking system and the electromechanical braking system can be provided for the electric automobile, the energy recovered by the regenerative braking system is fully utilized within the full working condition range of the electric automobile, and the endurance mileage of the electric automobile is improved.
In accordance with another aspect of the present invention, there is provided a control apparatus for a compound brake system, the compound brake system including an electromechanical brake system and a regenerative brake system, the electromechanical brake system being configured to generate a base brake torque, the regenerative brake system being configured to generate a regenerative brake torque, the control apparatus including:
the calculation module is used for acquiring a braking signal and calculating a required braking torque according to the braking signal;
the distribution module is used for distributing the basic braking torque and the regenerative braking torque according to the required braking torque and the current working condition;
and the control module is used for controlling the electromechanical braking system to form the basic braking torque and controlling the regenerative braking system to form the regenerative braking torque.
According to the control device of the composite braking system, the composite braking system comprises the electromechanical braking system and the regenerative braking system, so that the stability and the reliability of the system can be improved in a failure mode. The method comprises the steps of obtaining a braking signal, calculating a required braking torque according to the braking signal, distributing a basic braking torque and a regenerative braking torque according to the required braking torque and the current working condition, and finally controlling an electromechanical braking system to form the basic braking torque and controlling the regenerative braking system to form the regenerative braking torque. Therefore, the cooperative braking function of the regenerative braking system and the electromechanical braking system can be provided for the electric automobile, the energy recovered by the regenerative braking system is fully utilized within the full working condition range of the electric automobile, and the endurance mileage of the electric automobile is improved. In addition, because a hydraulic brake system is not used, mechanical connection can be reduced, hydraulic brake pipelines can be removed, the quality of the whole automobile can be effectively reduced, the size of the electric automobile is reduced, and the difficulty of arrangement and assembly is reduced. In addition, a hydraulic brake system is not needed, so that the brake fluid does not need to be replaced, and the condition that the brake fluid leaks to cause environmental pollution can be avoided.
In another aspect of the present application, an electric vehicle is provided, which includes a memory, a processor; wherein the processor executes a program corresponding to the executable program code by reading the executable program code stored in the memory, so as to implement the control method of the composite brake system as set forth in the above embodiments.
In yet another aspect, the present application provides a computer-readable storage medium storing computer-readable instructions for causing a computer to execute a method for controlling a composite brake system as set forth in the above embodiments.
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 schematic flow chart illustrating a method for controlling a hybrid brake system according to an embodiment of the present disclosure;
fig. 2 is a schematic flowchart of a control method of a compound brake system according to a second embodiment of the present application;
fig. 3 is a flowchart illustrating a control method of a compound brake system according to a third embodiment of the present application;
fig. 4 is a schematic structural diagram of a compound brake system according to a fourth embodiment of the present application;
fig. 5 is a schematic structural diagram of a high-voltage electromechanical brake according to a fifth embodiment of the present application;
FIG. 6 is a schematic diagram of the braking torque distribution of the electric vehicle in the embodiment of the present application;
fig. 7 is a schematic structural diagram of a control device of a compound brake system according to a sixth embodiment of the present application;
fig. 8 is a schematic structural diagram of a control device of a compound brake system according to a seventh 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 only for the purpose of explaining the present application and are not to be construed as limiting the present application. On the contrary, the embodiments of the application include all changes, modifications and equivalents coming within the spirit and terms of the claims appended hereto.
A control method and apparatus of a compound brake system according to an embodiment of the present application will be described below with reference to the accompanying drawings. Before describing the embodiments of the present application in detail, for the sake of understanding, common technical terms are first introduced:
CAN, Controller Area Network (Controller Area Network).
Fig. 1 is a schematic structural diagram of a control method of a compound brake system according to an embodiment of the present application.
The embodiment of the present application is exemplified in that the control method of the composite brake system is configured in the control device of the composite brake system, and the control device of the composite brake system may be configured in any electric vehicle, so that the electric vehicle can execute the control function of the composite brake system.
In an embodiment of the application, the hybrid braking system includes an electromechanical braking system and a regenerative braking system, wherein the electromechanical braking system is configured to form a basic braking torque, and the regenerative braking system is configured to form a regenerative braking torque.
In an embodiment of the present application, an electromechanical braking system includes at least: at least one high voltage electromechanical brake, wherein the operating voltage of the high voltage electromechanical brake is higher than 48V. Braking is performed by controlling at least one high-voltage electromechanical brake in the electromechanical braking system to form a base braking torque.
In the prior art, the low-voltage electronic mechanical brake system has the problems of weak capacity of a low-voltage storage battery and motor performance, complex transmission machinery and high control difficulty.
In the embodiment of the application, the working voltage of the high-voltage electromechanical brake in the electromechanical braking system is higher than 48V, so that the power and the torque of a motor in the electromechanical braking system can be improved, the requirement on a transmission part is reduced, the hardware structure is reduced, and the control precision is improved. In addition, because a hydraulic electronic mechanical brake system in the prior art is not used, mechanical connection can be reduced, a hydraulic brake pipeline is removed, the quality of the whole vehicle can be effectively reduced, the size of the electric vehicle is reduced, and the difficulty of arrangement and assembly is reduced. In addition, a hydraulic electronic mechanical brake system is not needed, and brake fluid can not be replaced, so that the situation of environmental pollution caused by brake fluid leakage can be avoided.
The number of the high-voltage electromechanical brakes may be at least one, for example, four, and the high-voltage electromechanical brakes are respectively arranged on each wheel of the electric vehicle, that is, the high-voltage electromechanical brakes may be respectively arranged on a front axle wheel and a rear axle wheel of the electric vehicle.
In an embodiment of the present application, a regenerative braking system includes at least: the regenerative braking system can perform regenerative braking by driving the power motor so as to form regenerative braking torque.
As shown in fig. 1, the control method of the compound brake system may include the steps of:
and 101, acquiring a braking signal, and calculating a required braking torque according to the braking signal.
In the embodiment of the application, the composite braking system can comprise a brake pedal sensor, and the brake pedal sensor can acquire a brake signal. Specifically, after the driver steps on the brake pedal, the brake pedal sensor may generate a brake signal and send the brake signal to the control device of the composite brake system, and accordingly, the control device of the composite brake system may calculate the required brake torque according to the brake signal after receiving the brake signal, for example, marking the required brake torque as Tdesire_brake。
As one kind canIn one implementation, the braking signals may include a brake pedal depth signal α and a brake pedal rate signal β, and the control device of the hybrid braking system may calculate a braking deceleration a of the electric vehicle according to α and β, i.e., a ═ f (α), and determine a required braking torque T of the electric vehicle according to the braking deceleration adesire_brake。
And 102, distributing basic braking torque and regenerative braking torque according to the required braking torque and the current working condition.
According to the control method of the composite braking system, the composite braking system comprises the electromechanical braking system and the regenerative braking system, so that the stability and the reliability of the system can be improved under a failure mode. The method comprises the steps of obtaining a braking signal, calculating a required braking torque according to the braking signal, distributing a basic braking torque and a regenerative braking torque according to the required braking torque and the current working condition, and finally controlling an electromechanical braking system to form the basic braking torque and controlling the regenerative braking system to form the regenerative braking torque. Therefore, the cooperative braking function of the regenerative braking system and the electromechanical braking system can be provided for the electric automobile, the energy recovered by the regenerative braking system is fully utilized within the full working condition range of the electric automobile, and the endurance mileage of the electric automobile is improved. In addition, because a hydraulic brake system is not used, mechanical connection can be reduced, hydraulic brake pipelines can be removed, the quality of the whole automobile can be effectively reduced, the size of the electric automobile is reduced, and the difficulty of arrangement and assembly is reduced. In addition, a hydraulic brake system is not needed, so that the brake fluid does not need to be replaced, and the condition that the brake fluid leaks to cause environmental pollution can be avoided.
In the embodiment of the application, the current working conditions are different, and the distributed basic braking torque and the distributed regenerative braking torque can be the same or different.
As a possible implementation, the regenerative braking torque may be generated according to the current operating condition, for example, the regenerative braking torque is marked as Tregen_brakeAnd braking torque T according to demanddesire_brakeAnd regenerative braking torque Tregen_brakeGenerating foundation braking torque, e.g. marking foundationMoment of force Tbasic_brakeWherein, Tbasic_brake+Tregen_brake＝Tdesire_brake. That is, the regenerative braking torque is only related to the current operating conditions, and may be the same or different when the current operating conditions are different.
For example, when the current operating condition is a pure electromechanical braking operating condition, in the state of the pure electromechanical braking operating condition, when the electric quantity of the power battery is greater than a preset threshold value, or the communication between the electromechanical braking system and the regenerative braking system fails, or the regenerative braking system fails, at this time, the power motor cannot provide the regenerative braking torque, that is, the regenerative braking system cannot form the regenerative braking torque, so that the regenerative braking torque T can be setregen_brakeSet to zero, demand braking torque Tdesire_brakeAll by basic braking torque Tbasic_brakeProviding, i.e. Tdesire_brake＝Tbasic_brake。
The preset threshold may be a threshold for allowing the power battery to perform regeneration feedback.
Alternatively, when the ABS control threshold is triggered during braking, if the regenerative braking system and the electromechanical braking system operate simultaneously, a situation in which the regenerative braking system oscillates may occur, taking into account the characteristic difference between the electromechanical braking system and the regenerative braking system, resulting in a situation in which the ABS control is continuously deteriorated. Therefore, in the application, when the ABS control threshold is triggered in the braking process, the regenerative braking torque can be set to be zero, and the required braking torque T can be set to be zerodesire_brakeAs basic braking torque Tbasic_brakeThereby improving the stability of the composite braking system.
As another possible implementation, the basic braking torque T may be generated according to the current operating conditionbasic_brakeAnd braking torque T according to demanddesire_brakeAnd basic braking torque Tbasic_brakeGenerating regenerative braking torque Tregen_brake。
For example, when the current operating condition is the throttle release operating condition, in the state of the throttle release operating condition, when the accelerator pedal is not triggered and the brake pedal is not triggered, at this momentSince the brake pedal is not triggered, the brake pedal sensor will not generate a braking signal, and the required braking torque T cannot be determineddesire_brakeThe size of (2). Therefore, in the present application, in order to fully utilize the regenerative feedback characteristic of the power motor, energy recovery can be performed with a fixed regenerative braking torque. In particular, the base braking torque T can be adjustedbasic_brakeSet to zero, i.e. the electromechanical braking system does not participate in the braking process, and will regenerate the braking torque Tregen_brakeIs set to a fixed value so as to control the regenerative braking system to perform energy recovery according to the fixed value.
And 103, controlling the electromechanical braking system to form a basic braking torque, and controlling the regenerative braking system to form a regenerative braking torque.
In the embodiment of the application, after the basic braking torque and the regenerative braking torque are determined, the electromechanical braking system can be controlled to form the basic braking torque, and the regenerative braking system is controlled to form the regenerative braking torque. In particular, the braking torque distribution may be performed on the at least one high-voltage electromechanical brake according to a base braking torque to form a base braking torque, and the braking torque distribution may be performed on the power motor according to a regenerative braking torque to form a regenerative braking torque.
As a possible implementation manner, when the numbers of the high-voltage electromechanical brakes and the power motors are multiple and are respectively arranged on the front axle wheels and the rear axle wheels of the electric vehicle, after determining the basic braking torque and the regenerative braking torque, the basic braking torque distribution may be performed on the multiple high-voltage electromechanical brakes on the front axle wheels and the multiple high-voltage electromechanical brakes on the rear axle wheels respectively according to a preset front-rear axle braking force distribution curve, the basic braking torque and the regenerative braking torque, the regenerative braking torque distribution may be performed on the multiple power motors on the front axle wheels and the multiple power motors on the rear axle wheels respectively, then the multiple high-voltage electromechanical brakes on the front axle wheels and the multiple high-voltage electromechanical brakes on the rear axle wheels are respectively controlled to brake to form the basic braking torque, and the braking is performed on the multiple power motors on the front axle wheels and the multiple power motors on the rear axle wheels to form the regenerative braking torque A braking torque is generated.
That is, after the base braking torque is determined, the braking force distribution curve for the front and rear axles and the base braking torque T may be preset according tobasic_brakeDistributing braking torque to a plurality of high-voltage electromechanical brakes on the front axle wheels and a plurality of high-voltage electromechanical brakes on the rear axle wheels, and respectively controlling the plurality of high-voltage electromechanical brakes on the front axle wheels and the plurality of high-voltage electromechanical brakes on the rear axle wheels to brake to form basic braking torque Tbasic_brake. In determining regenerative braking torque Tregen_brakeThen, the braking force distribution curve and the regenerative braking torque T of the front axle and the rear axle can be presetregen_brakeDistributing braking torque to a plurality of power motors on the front axle wheels and a plurality of power motors on the rear axle wheels, and respectively controlling the plurality of power motors on the front axle wheels and the plurality of power motors on the rear axle wheels to brake to form regenerative braking torque Tregen_brake. Therefore, the cooperative braking function of the regenerative braking system and the electromechanical braking system can be provided for the electric automobile, the energy recovered by the regenerative braking system is fully utilized within the full working condition range of the electric automobile, and the endurance mileage of the electric automobile is improved.
According to the control method of the composite braking system, the composite braking system comprises the electromechanical braking system and the regenerative braking system, so that the stability and the reliability of the system can be improved under a failure mode. The method comprises the steps of obtaining a braking signal, calculating a required braking torque according to the braking signal, distributing a basic braking torque and a regenerative braking torque according to the required braking torque and the current working condition, and finally controlling an electromechanical braking system to form the basic braking torque and controlling the regenerative braking system to form the regenerative braking torque. Therefore, the cooperative braking function of the regenerative braking system and the electromechanical braking system can be provided for the electric automobile, the energy recovered by the regenerative braking system is fully utilized within the full working condition range of the electric automobile, and the endurance mileage of the electric automobile is improved.
As a possible implementation manner, the current working condition includes a composite braking working condition, and in a state of the composite braking working condition, both the regenerative braking system and the electromechanical braking system work, that is, neither the regenerative braking system nor the electromechanical braking system has a fault, and at this time, the regenerative braking system and the electromechanical braking system can cooperatively brake. The above process is described in detail below with reference to fig. 2.
Fig. 2 is a flowchart illustrating a control method of a compound brake system according to a second embodiment of the present application.
As shown in fig. 2, the control method of the compound brake system may specifically include the steps of:
step 201, obtaining a braking signal, and calculating a required braking torque according to the braking signal.
The execution process of step 201 may refer to the execution process of step 101 in the above embodiments, and is not described herein again.
Step 202, obtaining a current available regenerative braking torque.
In the embodiment of the application, the control device of the composite braking system can acquire the currently available regenerative braking torque of the electric automobile from the power motor controller assembly. Specifically, the power motor controller assembly may be connected to all power motors and power batteries in the electric vehicle, and obtain first parameter information of the power batteries in the electric vehicle and second parameter information of all power motors, where the first parameter information includes parameter information such as electric quantity, and the second parameter information includes parameter information such as current, and the power motor controller assembly may calculate a current available regenerative braking torque according to the first parameter information of the power batteries and the second parameter information of all power motors.
Step 203, determining whether the required braking torque is less than or equal to the current available regenerative braking torque, if so, executing step 204, and if not, executing step 205.
And step 204, setting the basic braking torque to be zero, and taking the required braking torque as the regenerative braking torque.
In the embodiment of the application, when the demand braking torque is smaller than or equal to the current available regenerative braking torque, at the moment, the regenerative braking system can independently form the demand braking torque, and in order to recover electric energy to the maximum extent and improve the endurance mileage of the electric automobile, the basic braking torque can be set to zero, and the demand braking torque is taken as the regenerative braking torque, so that only the regenerative braking system is utilized for braking, and the energy is recovered to the maximum extent.
And step 205, taking the current available regenerative braking torque as the regenerative braking torque, making a difference between the required braking torque and the regenerative braking torque, and taking the difference as the basic braking torque.
In the embodiment of the application, when the required braking torque is larger than the current available regenerative braking torque, at the moment, the regenerative braking system cannot form the required braking torque alone, in order to recover electric energy to the maximum extent and improve the endurance mileage of the electric automobile, the current available regenerative braking torque can be used as the regenerative braking torque, the required braking torque and the regenerative braking torque are differenced, and the difference value is used as the basic braking torque, so that the regenerative braking system and the electronic mechanical braking system cooperatively brake.
And step 206, controlling the electromechanical braking system to form a basic braking torque, and controlling the regenerative braking system to form a regenerative braking torque.
The control method of the composite braking system of the embodiment of the application has the advantages that when the current working condition is the composite braking working condition, firstly, judging whether the current available regenerative braking torque is larger than or equal to the required braking torque or not, if so, it is indicated that the regenerative braking system alone can form the required braking torque, at this time, the base braking torque can be set to zero, and the required braking torque is taken as the regenerative braking torque, therefore, the electric energy is recovered to the maximum extent, the endurance mileage of the electric automobile is improved, if the electric automobile is not powered on, the regenerative braking system cannot form the required braking torque alone, at the moment, the current available regenerative braking torque can be used as the regenerative braking torque, the difference is made between the required braking torque and the regenerative braking torque, the difference is used as the basic braking torque, and the regenerative braking system and the electromechanical braking system cooperatively brake to fully utilize the regenerative braking function of the regenerative braking system.
As a possible implementation manner, the current operating condition includes a basic brake failure operating condition, and in a state of the basic brake failure operating condition, the electromechanical brake system has a fault, if at least one high-voltage electromechanical brake on the front axle wheels has a fault or at least one high-voltage electromechanical brake on the rear axle wheels has a fault, for example, when the numbers of the high-voltage electromechanical brakes and the power motors are four and are respectively arranged on the front axle wheels and the rear axle wheels of the electric vehicle, if the high-voltage electromechanical brake on the left wheel of the front axle has a fault, at this time, if the high-voltage electromechanical brake on the right wheel of the front axle normally brakes, the left wheel and the right wheel of the front axle have a braking moment difference, and at this time, a yaw situation of the electric vehicle may occur. Therefore, in the application, when at least one high-voltage electromechanical brake on a front axle wheel fails or at least one high-voltage electromechanical brake on a rear axle wheel fails, an axle where the failed high-voltage electromechanical brake is located cannot form basic braking torque distributed by the axle, and at this time, a plurality of power motors on the axle can perform independent braking to weaken the braking effect. The above process is described in detail below with reference to fig. 3.
Fig. 3 is a flowchart illustrating a control method of a compound brake system according to a third embodiment of the present application.
As shown in fig. 3, on the basis of the embodiment shown in fig. 1, according to a preset front-rear axle braking force distribution curve, a basic braking torque, and a regenerative braking torque, basic braking torque distribution is respectively performed on a plurality of high-voltage electromechanical brakes on a front axle wheel and a plurality of high-voltage electromechanical brakes on a rear axle wheel, and regenerative braking torque distribution is respectively performed on a plurality of power motors on the front axle wheel and a plurality of power motors on the rear axle wheel, which may specifically include the following steps:
step 301, setting the basic braking torque distributed by the high-voltage electromechanical brakes on the axle where the failed high-voltage electromechanical brake is located to be zero.
In the embodiment of the application, when at least one high-voltage electromechanical brake on a front axle wheel fails or at least one high-voltage electromechanical brake on a rear axle wheel fails, an axle where the failed high-voltage electromechanical brake is located cannot form basic braking torque distributed by the axle, and at the moment, basic braking torque distributed by a plurality of high-voltage electromechanical brakes on the axle where the failed high-voltage electromechanical brake is located can be set to be zero.
And 302, performing basic braking torque distribution on a plurality of high-voltage electromechanical brakes on the other axle according to a preset front and rear axle braking force distribution curve, basic braking torque and regenerative braking torque, and performing regenerative braking torque distribution on a plurality of power motors on front axle wheels and a plurality of power motors on rear axle wheels respectively.
As a possible implementation, the base braking torque distributed to the front axle and the base braking torque distributed to the rear axle may be determined based on a preset front-rear axle braking force distribution curve and the base braking torque, so as to determine the base braking torque distributed to the other axle. For example, when the axle where the failed high-voltage electromechanical brake is located is the front axle, the basic brake torque distributed by the front axle and the basic brake torque distributed by the rear axle can be obtained after the brake torque distribution is performed on the plurality of high-voltage electromechanical brakes on the front axle wheels and the plurality of high-voltage electromechanical brakes on the rear axle wheels according to the preset front-rear axle brake force distribution curve and the basic brake torque, so that the basic brake torque distributed by the rear axle can be used as the basic brake torque distributed by another axle. After determining the allocated base braking torque for the other axle, a base braking torque allocation may be made to a plurality of high-voltage electromechanical brakes on the other axle. And meanwhile, according to a preset front and rear axle braking force distribution curve and regenerative braking torque, distributing regenerative braking torque to the plurality of power motors on the front axle wheels and the plurality of power motors on the rear axle wheels.
As another possible implementation manner, the basic braking torque distribution may be performed on a plurality of high-voltage electromechanical brakes on another axle according to the basic braking torque, and the regenerative braking torque distribution may be performed on a plurality of power motors on wheels of the front axle and a plurality of power motors on wheels of the rear axle according to a preset front-rear axle braking force distribution curve and regenerative braking torque.
As still another possible implementation manner, the basic braking torque distributed to the axle where the failed high-voltage electromechanical brake is located and the basic braking torque distributed to the other axle may be determined according to a preset front-rear axle braking force distribution curve and the basic braking torque, and the regenerative braking torque distributed to the axle where the failed high-voltage electromechanical brake is located and the regenerative braking torque distributed to the other axle may be determined according to the preset front-rear axle braking force distribution curve and the regenerative braking torque.
And for the other axle, respectively distributing the basic braking torque to the plurality of high-voltage electromechanical brakes on the other axle and distributing the regenerative braking torque to the plurality of power motors on the other axle according to the distributed basic braking torque and the regenerative braking torque.
The distributed basic braking torque and the regenerative braking torque can be added aiming at the axle where the high-voltage electronic mechanical brake with the fault is located, and the required braking torque distributed by the axle where the high-voltage electronic mechanical brake with the fault is located is obtained. And then, the current available regenerative braking torque of the located axle can be obtained from the power motor controller assembly, whether the current available regenerative braking torque of the located axle is larger than or equal to the required braking torque distributed by the located axle or not is judged, if yes, the required braking torque distributed by the located axle is used as the regenerative braking torque of the located axle, the braking torque of the plurality of power motors of the located axle is distributed according to the regenerative braking torque of the located axle, if not, the current available regenerative braking torque of the located axle is used as the regenerative braking torque of the located axle, and the braking torque of the plurality of power motors of the located axle is distributed according to the regenerative braking torque of the located axle. Thus, when a high-voltage electromechanical brake on one axle of the electric vehicle fails, the braking effect can be reduced by braking with the plurality of power motors on the axle.
For example, when the axle where the failed high-voltage electromechanical brake is located is the front axle, the power motor controller assembly may obtain first parameter information of the power battery, obtain second parameter information of the plurality of power motors on the front axle wheels, and calculate the currently available regenerative braking torque of the front axle according to the second parameter information of the plurality of power motors on the front axle wheels and the first parameter information of the power battery. And then, whether the current available regenerative braking torque of the front axle is larger than or equal to the required braking force distributed by the front axle or not can be judged, when the required braking torque distributed by the front axle is smaller than or equal to the current available regenerative braking torque of the front axle, at the moment, the regenerative braking system of the front axle can independently form the required braking torque distributed by the front axle, in order to realize maximum electric energy recovery, the endurance mileage of the electric automobile is improved, and the braking requirement can be met, the required braking torque distributed by the front axle can be used as the regenerative braking torque of the front axle, and the braking torque is distributed to a plurality of power motors of the front axle according to the regenerative braking torque of the front axle. And when the required braking torque distributed by the front axle is larger than the currently available regenerative braking torque of the front axle, the regenerative braking system of the front axle cannot independently form the required braking torque distributed by the located axle. In order to realize maximum electric energy recovery and increase the endurance mileage of the electric automobile, the currently available regenerative braking torque of the front axle can be used as the regenerative braking torque of the front axle, and the braking torque distribution can be performed on the plurality of power motors of the front axle according to the regenerative braking torque of the front axle, so that the plurality of power motors on the front axle can be controlled to brake to form the regenerative braking torque of the axle on which the power motors are located. Therefore, when the high-voltage electronic mechanical brake on the front axle of the electric automobile breaks down, the braking effect can be weakened by braking through the plurality of power motors on the front axle.
According to the control method of the composite braking system, when at least one high-voltage electronic mechanical brake on a front axle wheel fails or at least one high-voltage electronic mechanical brake on a rear axle wheel fails, a plurality of power motors on an axle where the failed high-voltage electronic mechanical brake is located are used for braking, so that the braking effect is weakened.
As a possible implementation, the compound brake system may include: the brake system comprises a brake pedal sensor, a plurality of high-voltage electromechanical brakes, a plurality of power motors, a high-voltage electromechanical brake controller, a brake foot feeling simulator, a plurality of transmissions, a power motor controller assembly, a power battery, a voltage reduction module and a brake pedal assembly. The control device of the composite brake system for executing the control method of the composite brake system according to the embodiment of the present application may specifically refer to a high-voltage electromechanical brake controller in the composite brake system.
As an example, when the number of the high-voltage electromechanical brakes is four, and the high-voltage electromechanical brakes are respectively arranged on the front wheels and the rear wheels of the electric vehicle, referring to fig. 4, fig. 4 is a schematic structural diagram of a compound braking system according to a fourth embodiment of the present application. As shown in fig. 4, the compound brake system may include: the brake system comprises a brake pedal sensor 101, four high-voltage electromechanical brakes 102, four power motors 104, a high-voltage electromechanical brake controller 105, a brake foot feeling simulator 106, four transmissions 107, a power motor controller assembly 108, a high-voltage power battery 109, a voltage reduction module 110 and a brake pedal assembly 111.
Each transmission 107 is fixedly connected with the corresponding power motor 104, and the transmissions 107 are used for providing speed reduction and torque increase functions for the electric automobile. Brake pedal sensor 101 and brake feel simulator 106 are fixedly attached to brake pedal assembly 111, and brake pedal sensor 101 may be comprised of multiple springs and damping rubber.
In the embodiment of the application, the regenerative braking system and the electromechanical braking system share the power battery as a voltage source, and the voltage reduction module is used for reducing the voltage of the power supply voltage of the power battery and supplying power to the electromechanical braking system.
In the embodiment of the application, the voltage reduction module may be, for example, a Direct Current converter (DC-DC), and since the power battery is a high voltage battery, and the voltage is as high as 600V to 1000V, the voltage reduction module may reduce the voltage of the power supply voltage of the power battery to obtain the high voltage electricity required by the electromechanical braking system, and the high voltage electricity is connected to the high voltage electromechanical braking controller through the high voltage wire to supply power to the electromechanical braking system.
The power motor controller assembly can be directly connected with the power battery through the high-voltage conducting wire, consumes the electric energy of the power battery when controlling the plurality of power motors to drive, and controls the power motors to recycle the electric energy when controlling the power motors to perform regenerative braking so as to supplement the electric energy of the power battery, therefore, the regenerative braking system can be fully utilized to recycle the energy, and the endurance mileage of the electric automobile is improved. Wherein, the power motor is connected with the wheel and is used for transmitting the motor torque to the wheel, the tire and the ground.
The composite braking system of the embodiment of the application adopts mechanical and electrical connection, can improve the speed of signal transmission, the speed of braking response, the transmission efficiency and reduce the consumption of energy. And the composite braking system has a decoupling characteristic, and can couple the regenerative braking torque and the basic braking torque according to the braking requirement of the whole vehicle, so that the cooperative braking function of the regenerative braking system and the electromechanical braking system is provided. Specifically, through setting up the brake pedal simulator that directly links with brake pedal, provide adjustable brake pedal for the user and feel, satisfy the electric automobile's of different grade type brake pedal and feel the demand, and then accomplish basic braking moment and power motor regenerative braking's composite braking function.
In the embodiment of the application, when a plurality of power motors carry out regenerative braking, high-voltage electronic mechanical brake controller can distribute suitable braking force ratio according to different working conditions, and braking torque distribution is carried out to a plurality of high-voltage electronic mechanical brakes and a plurality of power motors to realize retrieving electric energy to the maximize, promote electric automobile's continuation of the journey mileage. That is to say, through the decoupling characteristic of the composite braking system, the regenerative braking torque and the basic braking torque can be distributed according to any proportion, so that the energy recovered by the regenerative braking system is fully utilized, and the endurance mileage of the electric automobile is improved.
As a possible implementation manner, referring to fig. 5, on the basis of the embodiment shown in fig. 4, the high-voltage electromechanical brake 102 specifically includes: the brake caliper comprises a brake disc 1011, brake pads 1012 distributed on two sides of the brake disc 1011, a caliper housing 1013, a speed reducing mechanism 1014 arranged in the caliper housing 1013, a pressure plate 1015 connected with the speed reducing mechanism 1014, and a high-voltage brake motor 1016 fixedly connected with the caliper housing 1013.
The high-pressure brake motor 1016 is used for driving the pressure plate 1015 to press the brake friction plate 1012 through the speed reduction mechanism 1014 to brake.
In the embodiment of the present application, the number of the brake pads 1012 is at least one, and fig. 5 only exemplifies that the number of the brake pads 1012 is 2.
In the embodiment of the present application, the high-pressure brake motor 1016 can drive the pressure plate 1015 to press against the brake friction plate 1012 through the speed reduction mechanism 1014 to perform braking. Specifically, the high-voltage brake motor 1016 may include a stator and a rotor, wherein the stator and the housing are assembled on the caliper housing 1013, the rotor is fixedly connected to the speed reduction mechanism 1014 and the pressure plate 1015, the rotation of the rotor is converted into the translation of the pressure plate 1015 through the action of the speed reduction mechanism 1014, the pressure plate 1015 is pushed to compress the brake pads 1012 distributed on both sides of the brake disc 1011, and braking is performed through friction between the brake pads 1012 and the brake disc 1011. Therefore, the foundation braking function can be provided for the electric automobile.
It should be noted that when the total braking torque required by the electric vehicle is reduced, the high-voltage braking motor 1016 rotates reversely, and the pull-down pressure plate 1015 returns to the original position. Therefore, when the total braking torque required by the electric automobile changes, braking can be performed through forward rotation or reverse rotation of the high-voltage braking motor 1016, and the flexibility of control is improved.
Step 102 will be described in detail below with reference to fig. 4.
1. The current working condition is the sliding working condition of the oil release door
Since the brake pedal sensor 101 does not generate a brake signal when the accelerator pedal is not activated and the brake pedal is not activated, energy recovery may be performed with a fixed regenerative braking torque in order to fully utilize regenerative feedback characteristics of the power motor 104. Specifically, the high voltage electromechanical brake controller 105 may brake the foundationMoment of force Tbasic_brakeSetting to zero, the electromechanical system does not participate in the braking process, and the regenerative braking torque T is obtainedregen_brakeThe energy recovery device is set to be a fixed value, so that the regenerative braking system is controlled to recover energy according to the fixed value, and the endurance mileage of the electric automobile is improved.
2. The current working condition is a pure electric mechanical braking working condition
When the electric quantity of the power battery of the electric vehicle is greater than the preset threshold value and exceeds the threshold value for allowing the regenerative feedback, or the regenerative braking system has a fault, for example, the power motor controller assembly has a fault, or the CAN communication fails, or the electromechanical braking system and the regenerative braking system have a communication failure, the power motor 104 cannot provide the regenerative braking torque, and at this time, the high-voltage electromechanical braking controller 105 may apply the regenerative braking torque Tregen_brakeSet to zero, demand braking torque Tdesire_brakeAll by basic braking torque Tbasic_brakeProviding, i.e. Tdesire_brake＝Tbasic_brake. At this time, the high-voltage electromechanical brake 102 provides the entire required braking torque, and the high-voltage electromechanical brake controller 105 may control the high-voltage electromechanical brake according to the preset front-rear axle braking force distribution curve and the base braking torque Tbasic_brakeThe braking torque distribution is performed for two high-voltage electromechanical brakes 102 on the front axle wheels and two high-voltage electromechanical brakes 102 on the rear axle wheels.
3. The current working condition is a composite braking working condition
When the regenerative braking system and the electromechanical braking system work normally, the regenerative braking system and the electromechanical braking system can cooperatively brake. First, the currently available regenerative braking torques of the four power batteries 104 on the electric vehicle, for example, labeled as T, can be obtainedregen_brake_availableWhen a braking demand is input, that is, after the driver steps on the brake pedal, the demanded braking torque T can be judged at this timedesire_brakeWhether or not the current available regenerative braking torque T is less than or equal toregen_brake_availableIf yes, let Tdesire_brake＝Tregen_brakeI.e. basic braking force Tbasic_brakeThe moment is zero, at the moment, all the required braking moments are provided by the four power motors 104, braking energy is recovered, and the endurance mileage of the electric automobile is increased; if not, the high-voltage electromechanical brake controller 105 firstly distributes the curve and the regenerative braking torque T according to the preset front and rear axle braking forceregen_brakeThe two power motors 104 on the front axle wheels and the two power motors 104 on the rear axle wheels are distributed with braking torque, and the rest braking torque is executed by the high-voltage electromechanical brake 102, namely the high-voltage electromechanical brake controller 105 is further executed according to the preset front and rear axle braking force distribution curve and the basic braking torque Tbasic_brakeThe braking torque distribution is performed for two high-voltage electromechanical brakes 102 on the front axle wheels and two high-voltage electromechanical brakes 102 on the rear axle wheels. Wherein, Tbasic_brake＝Tdesire_brake-Tregen_brake。
It should be noted that when the running speed of the electric vehicle changes, the inherent characteristics of the motor will cause the power motor 104 to regenerate the braking torque Tregen_brakeChange, therefore, in the present application, in order to ensure a consistent brake pedal feel, when the braking torque T is regeneratedregen_brakeWhen changed, the basic braking torque Tbasic_brakeCan be compensated correspondingly to realize the aim of realizing the aim of braking according to the regenerative braking torque Tregen_brakeTo the basic braking torque Tbasic_brakeAnd (5) performing dynamic adjustment. That is, during braking, T is always maintainedregen_brake+Tbasic_brake＝Tdesire_brakeThereby ensuring the stability of the braking process.
4. The current working condition is the basic brake failure working condition
When the electromechanical brake system has a fault, for example, a certain high-voltage electromechanical brake 102 on a front axle wheel or a rear axle wheel has a fault, at this time, in order to avoid the situation that the coaxial brake moment difference causes the whole vehicle to yaw, the other coaxial high-voltage electromechanical brake 102 cannot provide the brake moment. Thus, in the present application, the axle's allocated demand braking torque may be provided by both of the axle's power motors 104. Specifically, it can judgeCurrent available regenerative braking torque T of broken shaftregen_brake_availableWhether or not greater than the required braking torque T allocated to the axledesire_brakeIf yes, the required braking torque distributed by the shaft is used as the regenerative braking torque of the shaft, namely the T of the shaft is enabledregen_brake＝Tdesire_brakeIf not, the current available regenerative braking torque of the shaft is used as the regenerative braking torque of the shaft, namely, the T of the shaft is setregen_brake＝Tregen_brake_availableThereby, the braking effect can be weakened.
And for the other axle, because the high-voltage electromechanical brake does not break down, the regenerative braking system and the electromechanical braking system can perform cooperative braking.
5. Triggering ABS control threshold in braking process
When the ABS control threshold is triggered during braking, considering the characteristic difference between the electromechanical braking system and the regenerative braking system, if the regenerative braking system and the electromechanical braking system operate simultaneously, a situation of oscillation of the regenerative braking system may occur, resulting in a situation of continuous deterioration of the ABS control. Therefore, in the present application, when the ABS control threshold is triggered during braking, the regenerative braking function may be stopped, i.e. the regenerative braking torque is set to zero, and the high-voltage electromechanical brake controller 105 only sets the basic braking torque Tbasic_brakeThe four high-voltage electromechanical brakes 102 are distributed with braking torque, thereby improving the stability of the composite braking system, wherein T isbasic_brake＝Tdesire_brake。
As an example, referring to fig. 6, fig. 6 is a schematic diagram of braking torque distribution of an electric vehicle in the embodiment of the present application. Wherein, the high-voltage electronic mechanical brake controller 105 calculates the required braking torque as T after receiving the braking signal sent by the brake pedal sensor 101desire_brakeAnd calculating the regenerative braking torque T according to the current working condition of the electric automobileregen_brake. The high-voltage electromechanical brake controller 105 may also receive the currently available regenerative braking torque T sent by the power motor controller assembly 108regen_brake_availableJudgment ofBraking torque T for breaking demanddesire_brakeWhether or not the current available regenerative braking torque T is less than or equal toregen_brake_availableIf yes, let Tdesire_brake＝Tregen_brakeAt this time, the high-voltage electromechanical brake controller 105 controls the regenerative braking torque T and the braking force distribution curve of the front and rear axles according to the preset braking force distribution curve through the power motor controller assembly 108regen_brakeThe braking torque distribution is performed for two power motors on the front axle wheels and two power motors 104 on the rear axle wheels. If not, the high-voltage electronic mechanical brake controller 105 firstly passes through the power motor controller assembly 108 according to the preset front and rear axle brake force distribution curve and the regenerative brake torque Tregen_brakeThe two power motors on the front axle wheels and the two power motors 104 on the rear axle wheels are distributed with braking torque, and the rest of the braking torque is executed by the high-voltage electromechanical brake 102, i.e. the high-voltage electromechanical brake controller 105 can distribute the braking torque according to the preset front and rear axle braking force distribution curve and the basic braking torque Tbasic_brakeThe braking torque distribution is performed for the two high-voltage electromechanical brakes on the front axle wheels and the two high-voltage electromechanical brakes 102 on the rear axle of the rear axle wheels. Wherein, Tbasic_brake＝Tdesire_brake-Tregen_brake。
In order to implement the above embodiments, the present application also provides a control device of a composite brake system.
The composite braking system comprises an electromechanical braking system and a regenerative braking system, wherein the electromechanical braking system is used for forming a basic braking torque, and the regenerative braking system is used for forming a regenerative braking torque.
Fig. 7 is a schematic structural diagram of a control device of a compound brake system according to a sixth embodiment of the present application.
As shown in fig. 7, the control device of the compound brake system includes: a calculation module 610, an assignment module 620, and a control module 630.
And the calculating module 610 is used for acquiring the braking signal and calculating the required braking torque according to the braking signal.
As a possible implementation manner, the braking signal includes a brake pedal depth signal and a brake pedal change rate signal, and the calculating module 610 is specifically configured to: calculating the braking deceleration of the electric automobile according to the brake pedal depth signal and the brake pedal change rate signal; and determining the required braking torque according to the braking deceleration.
As another possible implementation manner, the calculating module 610 is specifically configured to: judging whether the required braking torque is less than or equal to the regenerative braking torque; if yes, setting the basic braking torque to be zero; if not, the difference is made between the required braking torque and the regenerative braking torque, and the difference is used as the basic braking torque.
And the distribution module 620 is used for distributing the basic braking torque and the regenerative braking torque according to the required braking torque and the current working condition.
As a possible implementation, the current operating condition includes a throttle release sliding operating condition, and in a state of the throttle release operating condition, the accelerator pedal is not triggered and the brake pedal is not triggered, and the allocating module 620 is specifically configured to: setting the basic braking torque to zero; the regenerative braking torque is set to a fixed value.
As another possible implementation manner, the current operating condition includes a pure electromechanical braking operating condition, and in the state of the pure electromechanical braking operating condition, the current operating condition is greater than a preset threshold, or the electromechanical braking system fails to communicate with the regenerative braking system, or the regenerative braking system fails, or an ABS control threshold is triggered in the braking process, and the allocating module 620 is specifically configured to: setting the regenerative braking torque to zero; the required braking torque is taken as the basic braking torque.
And a control module 630, configured to control the electromechanical braking system to form a basic braking torque, and control the regenerative braking system to form a regenerative braking torque.
Further, in a possible implementation manner of the embodiment of the present application, referring to fig. 8, on the basis of the embodiment shown in fig. 7, the control device of the compound brake system further includes:
as a possible implementation manner, the current working condition comprises a composite braking working condition, and in the state of the composite braking working condition, the regenerative braking system and the electromechanical braking system work.
The obtaining module 640 is configured to obtain a currently available regenerative braking torque before distributing the basic braking torque and the regenerative braking torque according to the required braking torque and the current working condition.
The allocating module 620 is specifically configured to: judging whether the required braking torque is smaller than or equal to the current available regenerative braking torque; if the required braking torque is smaller than or equal to the current available regenerative braking torque, setting the basic braking torque to be zero, and taking the required braking torque as the regenerative braking torque; and if the required braking torque is larger than the current available regenerative braking torque, taking the current available regenerative braking torque as the regenerative braking torque, making a difference between the required braking torque and the regenerative braking torque, and taking the difference as the basic braking torque.
As a possible implementation manner, the obtaining module 640 is specifically configured to: acquiring a current available regenerative braking torque from a power motor controller assembly; the power motor controller assembly calculates the current available regenerative braking torque according to the first parameter information of the power battery and the second parameter information of the power motor.
As a possible implementation manner, the electromechanical braking system includes a plurality of high-voltage electromechanical brakes, the regenerative braking system includes a plurality of power motors, and the plurality of high-voltage electromechanical brakes and the plurality of power motors are respectively and correspondingly arranged on front axle wheels and rear axle wheels of the electric vehicle, wherein an operating voltage of the high-voltage electromechanical brakes is higher than 48V. The control module 630 is specifically configured to: according to a preset front and rear axle braking force distribution curve, basic braking torque and regenerative braking torque, basic braking torque distribution is respectively carried out on a plurality of high-voltage electronic mechanical brakes on a front axle wheel and a plurality of high-voltage electronic mechanical brakes on a rear axle wheel, and regenerative braking torque distribution is respectively carried out on a plurality of power motors on the front axle wheel and a plurality of power motors on the rear axle wheel; the method comprises the steps of controlling a plurality of high-voltage electromechanical brakes on front axle wheels and a plurality of high-voltage electromechanical brakes on rear axle wheels to brake respectively to form basic brake torque, and controlling a plurality of power motors on the front axle wheels and a plurality of power motors on the rear axle wheels to brake respectively to form regenerative brake torque.
As a possible implementation manner, the current operating condition includes a basic brake failure operating condition, and in a state of the basic brake failure operating condition, if at least one high-voltage electromechanical brake on the front axle wheel fails or at least one high-voltage electromechanical brake on the rear axle wheel fails, the control module 630 is specifically configured to: setting basic braking torque distributed by a plurality of high-voltage electronic mechanical brakes on an axle where a failed high-voltage electronic mechanical brake is located to be zero; and according to a preset front and rear axle braking force distribution curve, basic braking torque and regenerative braking torque, performing basic braking torque distribution on a plurality of high-voltage electromechanical brakes on the other axle, and performing regenerative braking torque distribution on a plurality of power motors on front axle wheels and a plurality of power motors on rear axle wheels respectively.
It should be noted that the explanation of the embodiment of the control method of the composite brake system in the foregoing embodiment of the present application is also applicable to the control device of the composite brake system in this embodiment, and details are not repeated here.
According to the control device of the composite braking system, the composite braking system comprises the electromechanical braking system and the regenerative braking system, so that the stability and the reliability of the system can be improved under a failure mode. The method comprises the steps of obtaining a braking signal, calculating a required braking torque according to the braking signal, distributing a basic braking torque and a regenerative braking torque according to the required braking torque and the current working condition, and finally controlling an electromechanical braking system to form the basic braking torque and controlling the regenerative braking system to form the regenerative braking torque. Therefore, the cooperative braking function of the regenerative braking system and the electromechanical braking system can be provided for the electric automobile, the energy recovered by the regenerative braking system is fully utilized within the full working condition range of the electric automobile, and the endurance mileage of the electric automobile is improved.
In order to implement the above embodiments, the present application also proposes a computer-readable storage medium.
The computer-readable storage medium of the embodiment of the present application stores computer-readable instructions for causing a computer to execute the control method of the composite brake system proposed in the foregoing embodiment of the present application.
It should be noted that, in the description of the present application, the terms "first", "second", etc. are used for descriptive purposes only and are not to be construed as indicating or implying relative importance. In addition, in the description of the present application, "a plurality" means two or more unless otherwise specified.
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 executable instructions for implementing specific logical functions or steps of the process, and the scope of the preferred embodiments of the present application includes other implementations 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 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 various steps or methods may be implemented in software or firmware stored in memory and executed by a suitable instruction execution system. For example, 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.
In addition, functional units in the embodiments of the present application may be integrated into one processing module, or each unit may exist alone physically, or two or more units are integrated into one module. The integrated module can be realized in a hardware mode, and can also be realized in a software functional module mode. The integrated module, if implemented in the form of a software functional module and sold or used as a stand-alone product, may also be stored in a computer readable storage medium.
The storage medium mentioned above may be a read-only memory, a magnetic or optical disk, etc.
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 do not necessarily 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 more embodiments or examples.
Although embodiments of the present application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present application, and that variations, modifications, substitutions and alterations may be made to the above embodiments by those of ordinary skill in the art within the scope of the present application.

Claims (11)

1. A control method of a compound brake system, characterized in that the compound brake system includes an electromechanical brake system for generating a base brake torque and a regenerative brake system for generating a regenerative brake torque, the control method of the compound brake system including the steps of:
obtaining a braking signal, and calculating a required braking torque according to the braking signal;
distributing the basic braking torque and the regenerative braking torque according to the required braking torque and the current working condition;
and controlling the electromechanical braking system to form the basic braking torque, and controlling the regenerative braking system to form the regenerative braking torque.
2. The control method of claim 1, wherein the braking signal includes a brake pedal depth signal and a brake pedal rate of change signal, and the calculating a demanded braking torque from the braking signal comprises:
calculating the braking deceleration according to the brake pedal depth signal and the brake pedal change rate signal;
and determining the required braking torque according to the braking deceleration.
3. The control method of claim 1, wherein the current operating condition comprises a throttle release coast condition, a throttle pedal not being activated and a brake pedal not being activated at the state of the throttle release condition, and wherein distributing the base braking torque and the regenerative braking torque based on the demanded braking torque and the current operating condition comprises:
setting the basic braking torque to zero;
setting the regenerative braking torque to a fixed value.
4. The control method according to claim 1, wherein the current operating condition includes a pure electromechanical braking operating condition, and in a state of the pure electromechanical braking operating condition, an electric quantity of a power battery is greater than a preset threshold, or a communication failure between the electromechanical braking system and the regenerative braking system occurs, or a fault occurs in the regenerative braking system, or an ABS control threshold is triggered during braking, and the allocating the basic braking torque and the regenerative braking torque according to the demanded braking torque and the current operating condition includes:
setting the regenerative braking torque to zero;
and taking the required braking torque as the basic braking torque.
5. The control method of claim 1, wherein the current operating condition comprises a compound braking operating condition, wherein the regenerative braking system and the electro-mechanical braking system are both active during a state of the compound braking operating condition, and wherein the control method further comprises, before allocating the base braking torque and the regenerative braking torque based on the demanded braking torque and the current operating condition:
acquiring a current available regenerative braking torque;
distributing the basic braking torque and the regenerative braking torque according to the required braking torque and the current working condition, and the method comprises the following steps:
judging whether the required braking torque is smaller than or equal to the current available regenerative braking torque;
if the required braking torque is smaller than or equal to the current available regenerative braking torque, setting the basic braking torque to be zero, and taking the required braking torque as the regenerative braking torque;
and if the required braking torque is larger than the current available regenerative braking torque, taking the current available regenerative braking torque as the regenerative braking torque, and taking the difference between the required braking torque and the regenerative braking torque as the basic braking torque.
6. The control method according to claim 5, wherein the obtaining of the currently available regenerative braking torque includes:
obtaining the current available regenerative braking torque from a power motor controller assembly; and the power motor controller assembly calculates the current available regenerative braking torque according to the first parameter information of the power battery and the second parameter information of the power motor.
7. The control method according to claim 1, wherein the electromechanical brake system includes a plurality of high-voltage electromechanical brakes, the regenerative brake system includes a plurality of power motors, the plurality of high-voltage electromechanical brakes and the plurality of power motors are respectively provided on front axle wheels and rear axle wheels of the electric vehicle, wherein an operating voltage of the high-voltage electromechanical brakes is higher than 48V, and the controlling the electromechanical brake system to form the base braking torque and the controlling the regenerative brake system to form the regenerative braking torque includes:
according to a preset front and rear axle braking force distribution curve, the basic braking torque and the regenerative braking torque, respectively performing basic braking torque distribution on the plurality of high-voltage electronic mechanical brakes on the front axle wheels and the plurality of high-voltage electronic mechanical brakes on the rear axle wheels, and respectively performing regenerative braking torque distribution on the plurality of power motors on the front axle wheels and the plurality of power motors on the rear axle wheels;
and the plurality of high-voltage electronic mechanical brakes on the front axle wheels and the plurality of high-voltage electronic mechanical brakes on the rear axle wheels are respectively controlled to brake so as to form the basic braking torque, and the plurality of power motors on the front axle wheels and the plurality of power motors on the rear axle wheels are respectively controlled to brake so as to form the regenerative braking torque.
8. The control method according to claim 7, wherein the current operating condition includes a basic brake failure operating condition, and in a state of the basic brake failure operating condition, if at least one high-voltage electromechanical brake on a front axle wheel fails or at least one high-voltage electromechanical brake on a rear axle wheel fails, the basic brake torque distribution is performed on the plurality of high-voltage electromechanical brakes on the front axle wheel and the plurality of high-voltage electromechanical brakes on the rear axle wheel respectively, and the regenerative brake torque distribution is performed on the plurality of power motors on the front axle wheel and the plurality of power motors on the rear axle wheel respectively, according to a preset front-rear axle brake force distribution curve and the basic brake torque and the regenerative brake torque, including:
setting basic braking torque distributed by the high-voltage electronic mechanical brakes on the axle where the high-voltage electronic mechanical brakes with faults are located to be zero;
and according to a preset front and rear axle braking force distribution curve, the basic braking torque and the regenerative braking torque, performing basic braking torque distribution on the plurality of high-voltage electromechanical brakes on the other axle, and performing regenerative braking torque distribution on the plurality of power motors on the front axle wheels and the plurality of power motors on the rear axle wheels respectively.
9. A control device of a compound brake system, characterized in that the compound brake system includes an electromechanical brake system for generating a base brake torque and a regenerative brake system for generating a regenerative brake torque, the control device of the compound brake system comprising:
the calculation module is used for acquiring a braking signal and calculating a required braking torque according to the braking signal;
the distribution module is used for distributing the basic braking torque and the regenerative braking torque according to the required braking torque and the current working condition;
and the control module is used for controlling the electromechanical braking system to form the basic braking torque and controlling the regenerative braking system to form the regenerative braking torque.
10. An electric vehicle is characterized by comprising a memory and a processor;
wherein the processor executes a program corresponding to the executable program code by reading the executable program code stored in the memory for implementing the control method of the compound brake system according to any one of claims 1 to 8.
11. A computer-readable storage medium storing computer-readable instructions for causing a computer to execute the control method of a compound brake system according to any one of claims 1 to 8.
CN201811459297.2A 2018-11-30 2018-11-30 Control method and device of composite braking system and electric automobile Pending CN111251898A (en)

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113085820A (en) * 2021-04-23 2021-07-09 精诚工科汽车系统有限公司 Redundant brake control method and system, brake system and storage medium
CN113895240A (en) * 2021-10-11 2022-01-07 同济大学 Hybrid electric vehicle coordinated regenerative braking control method based on brake pedal decoupling
CN114030361A (en) * 2020-07-29 2022-02-11 四川鼎鸿智电装备科技有限公司 Method and device for brake control of electric vehicle, electronic device, and storage medium

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1081005B1 (en) * 1999-09-01 2008-07-30 Denso Corporation Vehicle braking apparatus and vehicle braking method
CN102139694A (en) * 2010-12-30 2011-08-03 中国第一汽车集团公司 Regenerative braking control method for hybrid power car
CN103448559A (en) * 2013-08-20 2013-12-18 联合汽车电子有限公司 Motor braking control system for pure electric vehicle
CN104108316A (en) * 2014-04-12 2014-10-22 北京工业大学 Electrohydraulic-combined brake control method of battery electric vehicle
CN108068630A (en) * 2017-11-11 2018-05-25 合肥正美电源科技有限公司 A kind of braking energy of electric automobiles recovery control system
CN108656956A (en) * 2017-03-27 2018-10-16 杭州长江汽车有限公司 Electric vehicle brake method, system and electric vehicle

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1081005B1 (en) * 1999-09-01 2008-07-30 Denso Corporation Vehicle braking apparatus and vehicle braking method
CN102139694A (en) * 2010-12-30 2011-08-03 中国第一汽车集团公司 Regenerative braking control method for hybrid power car
CN103448559A (en) * 2013-08-20 2013-12-18 联合汽车电子有限公司 Motor braking control system for pure electric vehicle
CN104108316A (en) * 2014-04-12 2014-10-22 北京工业大学 Electrohydraulic-combined brake control method of battery electric vehicle
CN108656956A (en) * 2017-03-27 2018-10-16 杭州长江汽车有限公司 Electric vehicle brake method, system and electric vehicle
CN108068630A (en) * 2017-11-11 2018-05-25 合肥正美电源科技有限公司 A kind of braking energy of electric automobiles recovery control system

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
陈祝明: "《电子系统专题设计与制作》", 30 April 2012, 电子科技大学出版社 *

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114030361A (en) * 2020-07-29 2022-02-11 四川鼎鸿智电装备科技有限公司 Method and device for brake control of electric vehicle, electronic device, and storage medium
CN113085820A (en) * 2021-04-23 2021-07-09 精诚工科汽车系统有限公司 Redundant brake control method and system, brake system and storage medium
CN113085820B (en) * 2021-04-23 2022-05-27 精诚工科汽车系统有限公司 Redundant brake control method and system, brake system and storage medium
CN113895240A (en) * 2021-10-11 2022-01-07 同济大学 Hybrid electric vehicle coordinated regenerative braking control method based on brake pedal decoupling

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