Commercial vehicle braking deceleration control method and device, vehicle and storage medium

Abstract

The invention relates to the technical field of vehicle control, and discloses a commercial vehicle braking deceleration control method and device, a vehicle and a storage medium. The method comprises the steps that current braking operation information, running state information and the whole vehicle mass of the vehicle are obtained; according to the braking operation information and the running state information, determining a corresponding motor braking demand torque; the actual braking torque actually output by the motor is obtained in real time, and the difference value between the motor braking demand torque and the actual braking torque is calculated; when the difference value is larger than the deviation threshold value, an air pressure braking supplement instruction is generated according to the difference value, and an air pressure braking system is controlled to output corresponding compensation braking force so as to control the braking deceleration of the whole vehicle; wherein the deviation threshold value is determined according to the theoretical deceleration and the whole vehicle mass. According to the method, when the motor braking is weakened unexpectedly due to external conditions, air braking can be recognized in time and actively called for dynamic compensation, and therefore the braking stability is guaranteed.

Description

Technical Field

[0001] This application relates to the field of vehicle control technology, and in particular to a method, device, vehicle, and storage medium for controlling the braking deceleration of a commercial vehicle. Background Technology

[0002] With the widespread application of electric commercial vehicles, regenerative braking technology is widely used to improve driving range. Existing models mostly employ a composite braking system combining electric motor braking and pneumatic braking. In vehicles without EBS (Electronic Braking System), the electric motor braking is independently controlled by the vehicle controller based on pedal signals, while the pneumatic braking relies on the mechanical pedal travel for triggering; the two lack coordination. Initially, only the energy-recovering electric motor braking is typically engaged. When the road surface is slippery or ABS is activated, the electric motor braking must be quickly disengaged to prevent wheel lock-up. However, if the pneumatic braking has not yet intervened, this will cause a sudden drop in vehicle braking force and abrupt deceleration, affecting braking smoothness and safety. Summary of the Invention

[0003] In view of this, embodiments of this application provide a method, device, vehicle, and storage medium for controlling the braking deceleration of a commercial vehicle. In electric commercial vehicles without EBS configuration, when the motor braking is unexpectedly weakened or fails due to external conditions, the method can promptly identify and actively call upon the air pressure braking for dynamic compensation, thereby effectively solving the technical problems of sudden changes in vehicle braking deceleration, insufficient braking force, and decreased braking predictability.

[0004] In a first aspect, embodiments of this application provide a method for controlling the braking deceleration of a commercial vehicle, including: Obtain the vehicle's current braking operation information, operating status information, and overall vehicle weight; Based on the braking operation information and operating status information, the corresponding motor braking torque requirement is determined; The actual braking torque output by the motor is obtained in real time, and the difference between the motor braking demand torque and the actual braking torque is calculated. When the difference is greater than the deviation threshold, a pneumatic braking supplementary command is generated based on the difference, and the pneumatic braking system is controlled to output a corresponding compensating braking force to control the vehicle's braking deceleration; wherein, the deviation threshold is determined based on the theoretical deceleration and the vehicle's mass.

[0005] In an optional implementation, the braking operation information includes the brake pedal opening; the operating status information includes the vehicle speed; The step of determining the corresponding motor braking torque requirement based on the braking operation information and operating status information includes: The required braking torque of the basic motor is determined based on the vehicle speed and the brake pedal opening. The required braking torque of the motor is obtained by correcting the basic motor braking torque based on the total vehicle weight.

[0006] In an optional implementation, the vehicle mass is determined based on the driving force, rolling resistance, air resistance, gradient resistance, and measured acceleration during the vehicle's operation. The step of correcting the basic motor braking torque requirement based on the vehicle mass to obtain the motor braking torque requirement includes: The mass amplification factor is calculated based on the total vehicle mass and the vehicle's unloaded mass. The braking torque requirement of the basic motor is linearly amplified using the mass amplification factor to obtain the braking torque requirement of the motor.

[0007] In an optional implementation, the step of generating a pneumatic braking supplementary command based on the difference and controlling the pneumatic braking system to output a corresponding compensating braking force includes: The equivalent target air pressure driving force is determined based on the difference. Based on the preset mapping relationship between the pneumatic braking output gear and the pneumatic braking power, the output gear that matches the target pneumatic braking power is determined as the supplementary gear; Based on the supplementary gear, the air pressure braking supplementary command is generated and sent to the brake controller to control the air valve actuator to output air pressure braking of corresponding intensity.

[0008] In an optional implementation, the multiple pneumatic braking output gears are divided according to the controllable opening time of the air valve. The lowest gear corresponds to the pressure released by one minimum cycle opening, the highest gear corresponds to the pressure output under the maximum braking demand, and the intermediate gears are evenly or non-linearly distributed between the lowest and highest. Each pneumatic braking output gear is pre-calibrated with the corresponding pneumatic compression power.

[0009] In an optional implementation, the theoretical deceleration is determined based on the motor braking torque requirement and the vehicle mass.

[0010] In an optional implementation, the deviation threshold is a preset multiple of the torque calculated based on the theoretical deceleration and the vehicle mass.

[0011] Secondly, embodiments of this application provide a commercial vehicle braking deceleration control device, comprising: The acquisition module is used to acquire the vehicle's current braking operation information, operating status information, and overall vehicle weight. The calculation module is used to determine the corresponding motor braking torque requirement based on the braking operation information and operating status information. The calculation module is also used to obtain the actual braking torque output by the motor in real time, and to calculate the difference between the motor braking demand torque and the actual braking torque. The control module is used to generate a pneumatic braking supplementary command based on the difference when the difference is greater than the deviation threshold, and control the pneumatic braking system to output a corresponding compensating braking force to control the vehicle braking deceleration; wherein the deviation threshold is determined based on the theoretical deceleration and the vehicle mass.

[0012] Thirdly, embodiments of this application provide a vehicle, the vehicle including a processor and a memory, the memory storing a computer program, and the processor executing the computer program to implement the above-described commercial vehicle braking deceleration control method.

[0013] Fourthly, embodiments of this application provide a computer-readable storage medium storing a computer program, which, when executed on a processor, implements the aforementioned commercial vehicle braking deceleration control method.

[0014] The embodiments of this application have the following beneficial effects: This application effectively solves the problem of sudden changes in vehicle braking deceleration caused by unexpected weakening or failure of motor braking by introducing a dynamic coordination mechanism between electric motor braking and pneumatic braking in electric commercial vehicles without EBS configuration. This method determines the required torque for motor braking in real time based on braking operation information and operating status information, and then identifies the lack of braking force by monitoring the actual torque output deviation. When a significant deviation is detected, the system can actively generate a pneumatic braking supplementary command, controlling the pneumatic braking system to output corresponding compensating braking force, thereby achieving timely compensation for insufficient electric braking to ensure braking stability and braking performance as expected. Attached Figure Description

[0015] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 This paper shows a first flowchart of a commercial vehicle braking deceleration control method according to an embodiment of the present application; Figure 2 This paper illustrates a second flowchart of a commercial vehicle braking deceleration control method according to an embodiment of this application. Figure 3 A schematic diagram of the third process of the commercial vehicle braking deceleration control method according to an embodiment of this application is shown; Figure 4The fourth flowchart of the commercial vehicle braking deceleration control method according to an embodiment of this application is shown; Figure 5 A schematic diagram of a commercial vehicle braking deceleration control device according to an embodiment of this application is shown. Detailed Implementation

[0017] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments.

[0018] The components of the embodiments of this application described and illustrated in the accompanying drawings can be arranged and designed in a variety of different configurations. Therefore, the following detailed description of the embodiments of this application provided in the drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0019] In the following text, the terms "comprising," "having," and their cognates, which may be used in various embodiments of this application, are intended only to indicate a particular feature, number, step, operation, element, component, or combination thereof, and should not be construed as primarily excluding the presence of one or more other features, numbers, steps, operations, elements, components, or combinations thereof, or adding the possibility of one or more combinations thereof. Furthermore, the terms "first," "second," "third," etc., are used only for distinguishing descriptions and should not be construed as indicating or implying relative importance.

[0020] Unless otherwise specified, all terms used herein (including technical and scientific terms) shall have the same meaning as commonly understood by one of ordinary skill in the art to which the various embodiments of this application pertain. Terms (such as those defined in commonly used dictionaries) shall be interpreted as having the same meaning as in their contextual meaning in the relevant technical field and shall not be construed as having an idealized or overly formal meaning, unless clearly defined in the various embodiments of this application.

[0021] The following detailed description of some embodiments of this application is provided in conjunction with the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0022] With the rapid development of electric vehicle technology, electrified powertrain systems have been gradually applied to the commercial vehicle sector. In electric commercial vehicles, regenerative braking has become a crucial means of improving the vehicle's range. By reversing the motor to achieve regenerative braking, some kinetic energy can be converted into electrical energy and stored in the battery during vehicle deceleration or coasting, thereby improving energy efficiency. Therefore, electric commercial vehicles now commonly employ a composite braking system combining motor braking and pneumatic braking, working together under different operating conditions to balance braking safety, energy recovery efficiency, and driver experience.

[0023] In the passenger vehicle sector, due to the relatively light weight of the vehicles and the high requirements for braking smoothness and comfort, hydraulic braking systems are often used, combined with electro-hydraulic braking systems (EHB) to achieve precise coordinated control between electric motor braking and hydraulic braking. The EHB system can dynamically distribute the ratio of the two braking forces according to the driver's braking intention and vehicle status, ensuring smooth and continuous deceleration output of the vehicle and avoiding sudden deceleration problems caused by the disengagement of electric motor braking.

[0024] However, in the commercial vehicle sector, the vehicle's weight and load capacity are significantly greater than those of passenger cars, resulting in a greater demand for braking force. Therefore, air-pressure braking systems, which offer rapid response and strong braking force, are commonly used as the primary braking method. Although some models have begun to be equipped with Electronic Braking System (EBS), which allows for precise coordination and control of electric motor braking and air-pressure braking, the high cost of EBS means that most commercial electric trucks and buses currently only have basic Anti-lock Braking System (ABS) or Electronic Stability Control (ESC) systems with integrated traction control. These systems lack the ability to actively coordinate electric motor braking and air-pressure braking; the two types of braking forces operate essentially independently.

[0025] Specifically, in existing electric commercial vehicles without EBS configurations, the motor braking is managed by the vehicle control unit (VCU) based on signals such as the brake pedal opening, while the air pressure braking mainly relies on a mechanical brake valve, with the air circuit being directly opened and closed by the driver's pedal stroke. Under normal circumstances, there is a period of free travel during the initial braking phase, during which only the motor braking is activated and the air pressure braking is not triggered to maximize energy recovery. Once the pedal travel exceeds a certain threshold, the air pressure braking gradually intervenes and is superimposed on the motor braking.

[0026] While this decoupled control architecture is simple and low-cost, it reveals significant safety and performance deficiencies under certain operating conditions. For example, when lightly applying the brakes on a wet or slippery road surface, if the ABS is activated, the vehicle controller will quickly reduce or completely disengage the electric motor braking to prevent the drive wheels from locking up. Since the brake pedal has not yet entered the air pressure intervention range at this time, the air pressure braking cannot be automatically supplemented, resulting in a sudden drop in the vehicle's braking force. This causes a significant reduction or even interruption in braking deceleration, and the driver perceives a weakened braking response, affecting the predictability of the braking system and driving safety.

[0027] Furthermore, when the power battery is fully charged (SOC close to 100%), or under abnormal operating conditions such as excessively high or low battery temperature, the Battery Management System (BMS) will limit the energy recovery capability of the motor, causing the motor braking to fail to output the expected braking torque. Similarly, in this scenario, without a corresponding compensation mechanism, the vehicle's braking deceleration will deviate from the expected level, compromising the predictability and consistency of the braking system.

[0028] Based on this, this application proposes an intelligent braking deceleration control method applicable to electric commercial vehicles without EBS configuration. When the motor braking is unexpectedly weakened or fails due to external conditions, the method can promptly identify the abnormal state and dynamically compensate by actively calling air pressure braking, thereby maintaining the stability and predictability of the vehicle's braking deceleration.

[0029] The following describes the braking deceleration control method for commercial vehicles using specific embodiments. This method is applicable to electric commercial vehicles equipped with a combined electric motor braking and pneumatic braking system, and is especially suitable for models without an electronic braking system (EBS). When the electric motor braking is unexpectedly weakened or fails due to external conditions, it can actively call in pneumatic braking for compensation, thereby maintaining the stability and predictability of the vehicle's braking deceleration.

[0030] Figure 1 A schematic flowchart of a commercial vehicle braking deceleration control method according to an embodiment of this application is shown. Exemplarily, the commercial vehicle braking deceleration control method includes steps S100-S400: Step S100: Obtain the vehicle's current braking operation information, operating status information, and overall vehicle weight.

[0031] In this embodiment, real-time vehicle operating data, including braking operation information and operating status information, is first collected via onboard sensors and the Controller Area Network (CAN) bus. The braking operation information includes at least the brake pedal opening signal, which can be detected by a displacement sensor installed at the brake pedal pivot point and transmitted to the vehicle controller (VCU) in analog voltage or digital communication form. The operating status information includes at least the vehicle's current speed, which can be obtained by collecting the rotational speeds of each wheel from wheel speed sensors, filtering the data to obtain the average speed value, and then sending it to the VCU via the CAN bus.

[0032] In addition, it is necessary to obtain the current vehicle mass, which is not a fixed parameter but a variable that changes dynamically with the cargo load. To achieve precise control, this embodiment uses a dynamic modeling method to estimate the vehicle mass online, that is, the vehicle mass is determined based on the driving force, rolling resistance, air resistance, gradient resistance, and measured acceleration during vehicle operation.

[0033] Specifically, based on Newton's second law, the following relationship is satisfied during the motion of the entire vehicle: ;in, The total vehicle mass is the problem to be solved. To measure the longitudinal acceleration of the entire vehicle (a is less than 0 when the vehicle decelerates), the data is directly collected by an inertial measurement unit (IMU) installed on the vehicle body. The driving force (the electric braking force generated by the motor, which is a positive value) is the braking force acting on the drive wheels under energy recovery conditions. It can be calculated by transmitting the braking torque output by the motor to the wheels through the transmission system. ,in, The braking torque on the motor shaft (defined as a positive value, indicating regenerative braking state), i is the main reduction ratio. Where r is the efficiency of the transmission system, and r is the tire rolling radius; As rolling resistance, it can be achieved through The estimate was obtained, among which, This is the road rolling resistance coefficient (which can be obtained through bench calibration). The unloaded curb weight of the vehicle. It is the acceleration due to gravity. The slope angle; Air resistance can be expressed by the formula Calculated, where, air density, Where A is the drag coefficient, A is the vehicle's frontal area, and v is the vehicle's current speed. As slope resistance, it can be achieved through It is calculated, but because it depends on the quality of the solution. Direct substitution will lead to circular coupling in the equations. To solve this circular dependency problem, an iterative initial value method can be used for approximation in this embodiment: First, assume the initial mass m(0) = Substitute into the above formula to estimate the initial slope resistance. Then, the updated mass estimate m(1) is calculated; the above process is repeated until the difference between two adjacent results is less than the preset convergence threshold (e.g., ±50kg), which is considered to have converged to the true mass. Alternatively, in a gentler slope (e.g., When the slope is large, the impact of slope resistance on mass estimation can be ignored; when the slope is large, real-time slope information can be obtained with the help of vehicle-mounted GPS elevation change rate to further improve the accuracy of mass estimation.

[0034] It is understandable that all the above parameters are obtained through existing vehicle sensors or pre-stored calibration parameters, requiring no additional hardware investment. In addition, the vehicle controller can periodically execute this mass estimation algorithm (e.g., once every 100ms) to achieve real-time tracking and updating of the vehicle's mass.

[0035] Step S200: Determine the corresponding motor braking torque requirement based on braking operation information and operating status information.

[0036] Among them, braking operation information includes brake pedal opening; operating status information includes vehicle speed; In some implementations, such as Figure 2 As shown, step S200 includes steps S210-S220: Step S210: Determine the required braking torque of the basic motor based on the vehicle speed and brake pedal opening. The basic electric motor braking torque requirement is an initial reference value before considering the influence of load. Its magnitude mainly depends on the driver's operation and the current vehicle speed. In this embodiment, a lookup table method is used to achieve rapid response. A two-dimensional mapping table is constructed in advance based on the ergonomic matching results of different combinations of vehicle speed and brake pedal opening during bench tests or real-vehicle tests. This mapping table is stored as an array in the non-volatile memory of the vehicle controller. For example, when the vehicle speed is 50 km / h and the brake pedal opening is 20%, the controller reads the corresponding basic electric motor braking torque requirement of 180 N·m from the mapping table. All mapping table data points are calibrated based on the principle of ensuring braking comfort and smoothness, ensuring that sufficient but not excessive braking force can be provided within the electric braking's independent operating range (i.e., within the brake pedal's free travel range).

[0037] Step S220: Correct the basic motor braking torque requirement based on the overall vehicle weight to obtain the motor braking torque requirement.

[0038] Since the actual vehicle weight is not fixed, using the baseline torque calibrated under no-load conditions will result in excessive braking force under light load and insufficient braking force under heavy load. Therefore, a mass compensation mechanism needs to be introduced to dynamically correct the baseline value.

[0039] Exemplary, such as Figure 3 As shown, step S220 includes steps S221-S222: Step S221: Calculate the mass amplification factor based on the total vehicle mass and the vehicle's unloaded mass. Step S222: The braking torque required by the basic motor is linearly amplified using a mass amplification factor to obtain the braking torque required by the motor.

[0040] Specifically, mass magnification factor / ;in, For the overall vehicle quality, This refers to the vehicle's unloaded mass. This mass magnification factor reflects the ratio of the current load to the baseline state. For example, if the unloaded mass is 8 tons and the current estimated mass is 14 tons, then... =1.75.

[0041] After obtaining the mass amplification factor, the basic motor braking torque requirement is combined with... This will give you the final motor braking torque requirement. Its calculation formula can be expressed as: Through this modification method in this embodiment, regardless of whether the vehicle is fully loaded or unloaded, it can output motor braking torque that matches its inertial mass, thereby effectively improving the adaptability and consistency of the braking system.

[0042] Step S300: Obtain the actual braking torque output by the motor in real time, and calculate the difference between the motor braking demand torque and the actual braking torque.

[0043] As an example, after calculating the required braking torque for the electric motor, the vehicle controller enters the monitoring phase to determine whether the electric motor braking can output normally as expected. Specifically, the controller periodically reads the actual braking torque value currently output by the motor from the motor controller via the CAN bus, i.e., the actual braking torque. This data is estimated in real time by the MCU based on current sensors and rotor position signals. Subsequently, the controller compares the required braking torque of the electric motor with the actual braking torque point by point, calculating the difference between the two. This difference reflects the degree of response deviation of the electric motor braking system. When the difference is close to zero, it indicates that the motor has accurately executed the control command; when the difference is significantly greater than zero, it indicates that there is a lack of braking force, which may be caused by one or more of the following reasons: the power battery SOC is too high, resulting in the inability to recover energy; the battery temperature exceeds the allowable operating range (e.g., below 0°C or above 55°C), limiting the motor's power generation capacity; the anti-lock braking system (ABS) is activated, and the VCU actively disengages the electric motor braking to prevent the drive wheels from locking; or the motor controller malfunctions or communication is interrupted, causing torque response lag or loss. It is understood that the above situations are all unexpected motor braking weakening, that is, not caused by changes in the driver's operating intention, but by abnormal exit caused by external system conditions. This embodiment will identify such unexpected situations and take corresponding compensation measures.

[0044] In step S400, when the difference is greater than the deviation threshold, a pneumatic braking supplementary command is generated based on the difference, and the pneumatic braking system is controlled to output the corresponding compensating braking force to control the vehicle braking deceleration.

[0045] Exemplary example: To avoid accidental triggering of pneumatic braking intervention due to normal fluctuations in motor torque or instantaneous deviations during control adjustment, this embodiment sets a dynamically adjustable deviation threshold as the criterion for determining whether to activate compensation control. Only when the difference between the motor's braking demand torque and the actual output torque exceeds this deviation threshold is it determined that there is a significant lack of braking force requiring intervention, and thus, pneumatic braking supplementary action is executed. It should be noted that the deviation threshold is not a fixed constant, but is dynamically adjusted according to the vehicle's current operating state to adapt to the braking response characteristics under different operating conditions. In some implementations, the deviation threshold is determined based on both the vehicle's theoretical deceleration and total vehicle mass.

[0046] Specifically, firstly, based on the motor braking torque requirement... and overall vehicle quality Determine the theoretical deceleration Its calculation formula can be Subsequently, the theoretical deceleration is combined with the vehicle mass, and a preset proportionality coefficient k is introduced to construct a deviation threshold. Its expression can be: The proportionality coefficient k is a dimensionless parameter with a value ranging from 0.1 to 0.3, and in some embodiments it can be set to 0.2. This parameter is determined through real vehicle calibration tests, taking into account the driver's sensitivity to deceleration changes and the system's response stability, ensuring that while avoiding frequent false triggers, it can promptly identify significant deceleration abrupt events that may affect braking predictability.

[0047] This embodiment employs the dynamic threshold method, which enables the system to have higher compensation sensitivity under high load or high deceleration demand conditions, while maintaining high fault tolerance under light load or low braking intensity scenarios, thereby achieving more reliable braking coordination control.

[0048] In some implementations, such as Figure 4 As shown, a pneumatic braking supplementary command is generated based on the difference, and the pneumatic braking system is controlled to output a corresponding compensating braking force, including steps S410-S430: Step S410: Determine the equivalent target gas suppression power based on the difference.

[0049] As an example, to achieve precise compensation for the lack of motor braking, the torque difference on the motor side needs to be converted into a physical quantity that the pneumatic braking system can respond to—that is, the longitudinal braking force acting on the drive wheels. Since both motor braking and pneumatic braking ultimately generate ground braking force at the tire contact point through the brake, an equivalent mechanical relationship between the two can be established at the wheel end.

[0050] Specifically, the difference between the motor braking torque requirement and the actual output torque is first calculated. (i.e., the braking torque difference on the motor shaft) (unit: N·m) is converted into the corresponding wheel-end braking force. (Unit: N), its calculation formula can be: Where i is the main reduction ratio; denoted as , where is the transmission system efficiency; 'r' is the tire rolling radius. The calculated values ​​are... This refers to the wheel-end braking force that the electric motor braking cannot provide under the current operating conditions. This force value serves as the target pneumatic braking force, representing the additional equivalent longitudinal braking force that the pneumatic braking system needs to apply to compensate for the deceleration loss caused by insufficient electric motor braking. Step S420: Based on the preset mapping relationship between air pressure braking output gear and air pressure power, determine the output gear that matches the target air pressure power as the supplementary gear.

[0051] Step S430: Generate a supplementary air pressure braking command based on the supplementary gear and send it to the brake controller to control the air valve actuator to output air pressure braking of the corresponding intensity.

[0052] Exemplary, multiple pneumatic braking output positions are divided according to the controllable opening time of the air valve. The lowest position corresponds to the pressure released by one minimum cycle opening, the highest position corresponds to the pressure output under the maximum braking demand, and the intermediate positions are evenly or non-linearly distributed between the lowest and the highest. Each pneumatic braking output position is pre-calibrated with the corresponding pneumatic compression power.

[0053] In this embodiment, considering that most commercial vehicles are not equipped with EBS systems and lack the ability to continuously adjust air chamber pressure, this embodiment uses a graded control strategy to approximate the target braking force. Specifically, the entire available air pressure braking range is divided into multiple discrete output levels, forming a limited but controllable adjustment method.

[0054] These pneumatic braking output levels are divided based on the controllable opening time of the air valve actuator. Each level corresponds to a different solenoid valve energization duration, thereby releasing different volumes of compressed air into the brake chamber, generating a stepped increase in braking pressure. The lowest level (level 1) corresponds to the air valve opening within a minimum control cycle (e.g., 10ms), releasing only a small amount of gas to generate slight braking force; the highest level (level 10) corresponds to the fully open state under maximum braking demand, providing braking force output close to the mechanical limit; the intermediate levels can be evenly distributed between the lowest and highest, or can be nonlinearly optimized according to actual braking sensitivity (e.g., denser low-level intervals and sparser high-level intervals) to improve control accuracy.

[0055] Each output gear is pre-calibrated through bench testing or real vehicle testing to determine its stable air compression force, and this mapping relationship is stored in the brake controller or vehicle controller in the form of a lookup table. During operation, the controller compares the target air compression force with the braking force corresponding to all gears, and selects the gear that is closest to and not less than the target air compression force as the final supplementary gear.

[0056] After determining the required supplemental gear, the vehicle controller generates a corresponding air pressure braking supplemental command. This command may include a specific gear number (e.g., activating gear 4) and an execution command (e.g., applying immediately). The command is sent to the brake controller via the standard CAN communication protocol. Upon receiving the command, the brake controller parses the gear information and controls the corresponding high-speed switching solenoid valve to open and close according to a preset time pattern, thereby precisely releasing the corresponding level of air pressure. For example, if gear 4 is selected, the controller will drive the solenoid valve to open for a specific duration, allowing the brake chamber to reach the target pressure level, pushing the brake pads against the brake drum to generate the required auxiliary braking force.

[0057] This process requires no modification to the existing pneumatic braking hardware; it only requires adding a communication interface and control logic at the software level. It's important to note that throughout the entire control process, the vehicle controller continuously monitors the difference changes in subsequent cycles. Once motor braking resumes (e.g., ABS disengages, battery regeneration is permitted), the pneumatic braking supplementary command is automatically revoked, the compensation mode is exited, and the vehicle re-enters an energy-saving operating state primarily based on motor braking.

[0058] This embodiment introduces a dynamic coordination mechanism between electric motor braking and pneumatic braking in electric commercial vehicles without EBS configurations, effectively addressing the problem of sudden changes in vehicle braking deceleration caused by unexpected weakening or failure of electric motor braking. The method estimates the vehicle's mass in real time based on its actual operating state and calculates the required torque for electric motor braking by combining information such as brake pedal opening and vehicle speed. It then identifies instances of insufficient braking force by monitoring deviations in actual torque output. When a significant deviation is detected, the system proactively generates a supplementary pneumatic braking command, using a tiered control strategy to match the optimal pneumatic braking output level. This enables timely compensation for insufficient electric braking, ensuring braking stability and predictable braking performance.

[0059] Figure 5 A schematic diagram of a commercial vehicle braking deceleration control device according to an embodiment of this application is shown. Exemplarily, the commercial vehicle braking deceleration control device includes: The acquisition module 100 is used to acquire the vehicle's current braking operation information, operating status information, and overall vehicle weight. The calculation module 200 is used to determine the corresponding motor braking torque requirement based on braking operation information and operating status information.

[0060] The calculation module 200 is also used to obtain the actual braking torque output by the motor in real time and calculate the difference between the motor braking demand torque and the actual braking torque.

[0061] The control module 300 is used to generate a pneumatic braking supplementary command based on the difference when the difference is greater than the deviation threshold, and control the pneumatic braking system to output the corresponding compensating braking force to control the vehicle braking deceleration; wherein, the deviation threshold is determined based on the theoretical deceleration and the vehicle mass.

[0062] It is understood that the device in this embodiment corresponds to the commercial vehicle braking deceleration control method in the above embodiment, and the options in the above embodiment are also applicable to this embodiment, so they will not be described again here.

[0063] This application also provides a vehicle, exemplary in that the vehicle includes a processor and a memory, wherein the memory stores a computer program, and the processor, by running the computer program, causes the vehicle to perform the functions of the various modules in the above-described commercial vehicle braking deceleration control method or the above-described commercial vehicle braking deceleration control device.

[0064] The processor can be an integrated circuit chip with signal processing capabilities. The processor can be a general-purpose processor, including at least one of a Central Processing Unit (CPU), Graphics Processing Unit (GPU), Network Processor (NP), Digital Signal Processor (DSP), Application-Specific Integrated Circuit (ASIC), Field-Programmable Gate Array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components. The general-purpose processor can be a microprocessor or any conventional processor, capable of implementing or executing the methods, steps, and logic block diagrams disclosed in the embodiments of this application.

[0065] The memory can be, but is not limited to, Random Access Memory (RAM), Read Only Memory (ROM), Programmable Read-Only Memory (PROM), Erasable Programmable Read-Only Memory (EPROM), Electrically Erasable Programmable Read-Only Memory (EEPROM), etc. The memory is used to store computer programs, and the processor can execute the computer programs accordingly after receiving execution instructions.

[0066] This application also provides a computer-readable storage medium for storing the computer program used in the aforementioned vehicle. For example, the computer-readable storage medium may include, but is not limited to, various media capable of storing program code, such as a USB flash drive, a portable hard drive, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.

[0067] In the several embodiments provided in this application, it should be understood that the disclosed apparatus and methods can also be implemented in other ways. The apparatus embodiments described above are merely illustrative. For example, the flowcharts and block diagrams in the accompanying drawings show the architecture, functionality, and operation of possible implementations of apparatus, methods, and computer program products according to various embodiments of this application. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing a specified logical function. It should also be noted that, in alternative implementations, the functions marked in the blocks may occur in a different order than those marked in the drawings. For example, two consecutive blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in the block diagram and / or flowchart, and combinations of blocks in the block diagram and / or flowchart, can be implemented using a dedicated hardware-based system that performs the specified function or action, or using a combination of dedicated hardware and computer instructions.

[0068] In addition, the functional modules or units in the various embodiments of this application can be integrated together to form an independent part, or each module can exist independently, or two or more modules can be integrated to form an independent part.

[0069] If the aforementioned functions are implemented as software functional modules and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a smartphone, personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application.

[0070] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application.

Claims

1. A commercial vehicle brake deceleration control method characterized by, The method comprises the following steps: obtaining the current brake operation information, running state information and vehicle mass of the vehicle; determining the corresponding motor braking demand torque according to the brake operation information and running state information; real-time obtaining the actual braking torque actually output by the motor, and calculating the difference between the motor braking demand torque and the actual braking torque; when the difference is greater than a deviation threshold, generating a pneumatic brake supplement instruction according to the difference, controlling the pneumatic brake system to output a corresponding compensation braking force, so as to control the vehicle braking deceleration; wherein the deviation threshold is determined according to the theoretical deceleration and the vehicle mass.

2. The commercial vehicle brake deceleration control method of claim 1, characterized by, The brake operation information includes brake pedal opening; the running state information includes vehicle speed; The method comprises the following steps: determining the basic motor braking demand torque according to the vehicle speed and the brake pedal opening; correcting the basic motor braking demand torque according to the vehicle mass to obtain the motor braking demand torque.

3. The commercial vehicle brake deceleration control method of claim 2, characterized by The vehicle mass is determined based on the driving force, rolling resistance, air resistance, slope resistance and measured acceleration during the driving process of the vehicle; The method comprises the following steps: calculating the mass amplification coefficient according to the vehicle mass and the vehicle unloaded mass; linearly amplifying the basic motor braking demand torque by using the mass amplification coefficient to obtain the motor braking demand torque.

4. The commercial vehicle brake deceleration control method of claim 1 wherein, The method comprises the following steps: determining the equivalent target pneumatic braking force according to the difference; determining the output gear matched with the target pneumatic braking force as the supplement gear according to the mapping relationship between the preset pneumatic brake output gear and pneumatic braking force; generating the pneumatic brake supplement instruction based on the supplement gear and sending it to the brake controller, so as to control the air valve actuator to output the corresponding strength of pneumatic braking.

5. The commercial vehicle braking deceleration control method according to claim 4, wherein a plurality of the pneumatic brake output gears are divided according to the controllable opening time of the air valve, the lowest gear corresponds to the pressure released by one minimum periodic opening, the highest gear corresponds to the pressure output under the maximum braking demand, and the intermediate gears are evenly or nonlinearly distributed between the lowest and highest gears; wherein each of the pneumatic brake output gears is pre-calibrated with a corresponding pneumatic braking force.

6. The commercial vehicle brake deceleration control method of claim 1 wherein, The theoretical deceleration is determined based on the motor braking demand torque and the vehicle mass.

7. The commercial vehicle brake deceleration control method of claim 1 wherein, The deviation threshold is a preset multiple of the torque calculated based on the theoretical deceleration and the vehicle mass.

8. A commercial vehicle brake reduction control device characterized by, The method comprises the following steps: an obtaining module, configured to obtain the current brake operation information, running state information and vehicle mass of the vehicle; a calculating module, configured to determine the corresponding motor braking demand torque according to the brake operation information and running state information; the calculating module is further configured to real-time obtain the actual braking torque actually output by the motor, and calculate the difference between the motor braking demand torque and the actual braking torque; The control module is configured to generate a pneumatic brake supplement instruction according to the difference when the difference is greater than a deviation threshold, and control the pneumatic brake system to output a corresponding compensation braking force to control the vehicle braking deceleration, wherein the deviation threshold is determined according to the theoretical deceleration and the vehicle mass.

9. A vehicle characterized by comprising: The vehicle comprises a processor and a memory, the memory stores a computer program, and the processor is configured to execute the computer program to implement the commercial vehicle braking deceleration control method according to any one of claims 1-7.

10. A computer-readable storage medium, characterized in that, The computer program is stored in the memory and is executed on the processor to implement the commercial vehicle braking deceleration control method according to any one of claims 1-7.

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