A new energy heavy truck inching control method and device

Abstract

This invention discloses a creep control method and device for a new energy heavy-duty truck, belonging to the field of new energy vehicle control technology. The method includes the following steps: in response to vehicle power-on, determining whether the vehicle is currently in a creep basic state, and if the doors are closed and the driver is in position, entering a creep waiting-to-recognize state; in the creep waiting-to-recognize state, if it is detected that the accelerator pedal is depressed beyond a preset opening degree and then released and returned to zero opening degree, then a creep power latch flag is set to an active state; when the creep power latch flag is active, the corresponding creep mode is activated according to the current vehicle gear information, the creep mode including a forward creep mode and a reverse creep mode; during creeping, creep torque is feedforward compensated according to the real-time slope value; when any one of the preset exit conditions is met, the creep mode is exited; wherein, if the met exit condition includes a creep basic state failure, the creep power latch flag is set to an inactive state. This invention improves the safety and driving smoothness of creep control under complex working conditions.

Description

Technical Field

[0001] This invention belongs to the field of new energy vehicle control technology, specifically relating to a creep control method and device for a new energy heavy-duty truck. Background Technology

[0002] Crawl control, also known as "low-speed cruise" or "creep" function, refers to a vehicle's ability to automatically maintain a low speed without the driver needing to press the accelerator pedal. This function is widely used in traditional gasoline-powered vehicles and new energy passenger vehicles, significantly improving handling convenience in scenarios such as traffic jams, slow maneuvering, and hill starts. With the advancement of the "dual-carbon" strategy, the penetration rate of new energy heavy-duty trucks in ports, mining areas, and long-haul logistics is rapidly increasing. However, directly applying the crawl control strategy derived from passenger vehicles to new energy heavy-duty trucks exposes many incompatibilities and safety hazards. First, there is insufficient safety redundancy, posing a risk of accidental movement. Existing solutions typically rely solely on basic conditions such as vehicle system readiness, gear position, braking, and throttle signals, failing to cover the complex actual operating scenarios of heavy-duty trucks. For example, if the driver engages the handbrake but leaves the vehicle without shifting to neutral, and the handbrake is accidentally released due to mechanical failure, misoperation, or thermal expansion and contraction, the vehicle will immediately enter a crawling state, leading to a "rollover" accident. Second, the control strategy is crude and fails to differentiate between driving modes. Most solutions use the same target speed and torque adjustment PID parameters for both forward (D) and reverse (R) creeping. However, heavy truck drivers have much higher requirements for the precision, smoothness, and safety of reverse creeping than forward creeping. A coarse, consistent control approach cannot meet the demands of refined operation. Finally, it suffers from poor adaptability to operating conditions and blind spots when starting on inclines. Traditional creeping torque is calibrated on flat roads and builds up slowly from zero. When the vehicle is on a slight incline, within the time window between releasing the brake pedal and the creeping torque being sufficient to overcome gravity, the vehicle will noticeably roll backward. This not only affects the driving experience but also poses a significant safety hazard in confined spaces or when there are obstacles behind the vehicle.

[0003] In summary, existing crawl control methods for new energy heavy-duty trucks have significant shortcomings in terms of safety, scenario adaptability, and control precision. There is an urgent need to design a dedicated crawl control method tailored to the characteristics of heavy-duty truck models, complex operating conditions, and higher safety requirements. Summary of the Invention

[0004] The technical problem to be solved by this invention is: how to improve the safety hazards, rough control and poor slope adaptability of new energy heavy trucks in creep control.

[0005] To solve the above-mentioned technical problems, the present invention provides a creep control method for new energy heavy-duty trucks, comprising the following steps: In response to the vehicle being powered on, determine whether the vehicle is currently in the basic creep state and whether the doors are closed and the driver is in the seat. If these conditions are met, enter the creep waiting recognition state. In the creep waiting recognition state, if it is detected that the accelerator pedal is pressed down to a preset opening degree and then released and returned to zero opening degree, the creep power latch flag is set to the valid state. When the creep driving capability latch flag is valid, the corresponding creep mode is activated according to the current vehicle gear information. The creep mode includes forward creep mode and reverse creep mode. During the creeping process, the creeping torque is fed forward to compensate based on the real-time slope value; When any one of the preset exit conditions is met, the creep mode is exited; wherein, if the exit condition includes a creep basic state failure, the creep power latch flag is set to an invalid state.

[0006] The aforementioned creep control method for new energy heavy-duty trucks includes the following criteria for determining whether the vehicle is in the basic creep state: the handbrake is released, the gear is in D or R, the vehicle is connected to high voltage and there is no charging signal.

[0007] The aforementioned creep control method for new energy heavy-duty trucks, wherein the forward creep mode is: the vehicle speed is set to the forward creep target speed, and a first set of PID control parameters is used; and the reverse creep mode is: the vehicle speed is set to the reverse creep target speed, and a second set of PID control parameters is used.

[0008] The aforementioned creep control method for new energy heavy-duty trucks includes a first set of PID control parameters comprising a first proportional coefficient and a first integral coefficient, and a second set of PID control parameters comprising a second proportional coefficient and a second integral coefficient; wherein the first proportional coefficient is greater than the second proportional coefficient, and the first integral coefficient is greater than the second integral coefficient, so that the forward creep target speed is greater than the reverse creep target speed.

[0009] The aforementioned creep control method for new energy heavy-duty trucks, wherein the feedforward compensation of the creep torque is performed by superimposing the feedforward compensation torque with the base creep torque to obtain the comprehensive creep torque, wherein the comprehensive creep torque is: , in, This indicates the combined creep torque command value. This represents the base creep torque calculated by the PID algorithm based on the deviation between the current vehicle speed and the target vehicle speed. This indicates the feedforward compensation torque.

[0010] The aforementioned creep control method for new energy heavy-duty trucks, wherein the feedforward compensation torque is calculated as follows: , in, θ Indicates the slope value; The sign indicates the direction of the slope; positive for uphill and negative for downhill. This refers to the compensation coefficient obtained or calculated based on the absolute value of the slope from a table. The absolute value of the slope table coefficient needs to be calibrated according to the specific vehicle model and working conditions. G This represents the gain estimated based on the total weight of the vehicle.

[0011] The aforementioned creep control method for new energy heavy-duty trucks includes the following exit conditions: the brake pedal is depressed, the driver's side door is opened, the driver leaves the seat, the handbrake is pulled up, the gear is switched to N or P, the charging signal is connected, and the vehicle is subjected to high voltage.

[0012] This invention also provides a creep control device for a new energy heavy-duty truck, applied to a vehicle controller, comprising: The status management module is used to respond to the vehicle power-on and determine whether the vehicle is in the basic creep state, and if the doors are closed and the driver is in the seat. If these conditions are met, the vehicle enters the creep waiting recognition state. The latch confirmation module is used to set the creep capability latch flag to an active state if it detects that the accelerator pedal has been pressed to a preset opening degree and then released and returned to zero opening degree when the creep waiting recognition state is in progress. The execution module is used to activate the corresponding crawl mode according to the current vehicle gear information when the crawling capability latch flag is valid. The crawl mode includes forward crawl mode and reverse crawl mode. The compensation module is used to feedforward compensation of the creeping torque based on the real-time slope value during the creeping process; The exit module is used to exit the creep mode when any one of the exit conditions in the preset exit condition set is met. If the exit condition includes the creep basic state, the creep power latch flag is set to an invalid state.

[0013] The present invention also provides a new energy heavy-duty truck, comprising: The sensor array is used to collect data on accelerator pedal opening, brake pedal status, gear position, door status, driver presence signal, and road slope value. The vehicle controller is used to execute the creep control method for any of the aforementioned new energy heavy-duty trucks.

[0014] The beneficial effects achieved by this invention are as follows: By using closed doors and driver presence as high-priority prohibition conditions and employing a latching mechanism, this invention prevents the vehicle from moving on its own due to misoperation, driver absence, or unclosed doors, thus improving the safety of the creep function. By differentiating the target speeds for forward and reverse creep and using PID control parameters, it improves the control precision and smoothness in reversing conditions, preventing jerking during reversing. Furthermore, by utilizing real-time slope information to feedforward compensate for the creep torque and superimposing it with the base creep torque for output, it achieves anti-rollover during hill starts and adaptive speed downhill. This enhances the safety and slope adaptability of the creep function for new energy heavy-duty trucks in complex scenarios such as depots, maintenance areas, and charging areas. Attached Figure Description

[0015] Figure 1 This is a flowchart of the creep control method of the present invention; Figure 2 This invention relates to the road feedforward compensation process. Detailed Implementation

[0016] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of 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, not all, of the embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0017] Example 1

[0018] This embodiment provides a creep control method for a new energy heavy-duty truck, applied to a vehicle controller, including the following steps: In response to the vehicle being powered on, the system determines whether the vehicle is currently in the basic crawling state. If the doors are closed and the driver is in the seat, the system enters the crawling waiting-for-recognition state. In the creep waiting recognition state, if it is detected that the accelerator pedal is pressed down to a preset opening degree and then released and returned to zero opening degree, the creep power latch flag is set to the valid state. When the creep driving capability latching flag is active, the corresponding creep mode is activated according to the current vehicle gear information. The creep mode includes forward creep mode and reverse creep mode. During the creeping process, the creeping torque is fed forward to compensate based on the real-time slope value; When any one of the preset exit conditions is met, the creep mode is exited. If the exit condition includes a creep basic state failure, the creep capability latch flag is set to an invalid state.

[0019] After the vehicle is powered on, the vehicle controller determines whether the vehicle is in the basic creep state. The basic creep state includes: the handbrake is released, the gear is in D or R, and the vehicle is connected to high voltage with no charging signal. Under the premise of meeting the basic creep state, two additional parallel high-priority prohibition conditions are added: whether the driver's side door is closed and whether the driver is in their seat.

[0020] The system enters the crawling pending recognition state only when all three conditions are met: the basic crawling condition is satisfied, the doors are closed, and the driver is in the vehicle. Specifically, the complete conditions for the crawling pending recognition state are: handbrake released, gear in D or R, vehicle connected to high voltage, no charging signal, doors closed, and driver in the vehicle. If any condition is not met, the vehicle controller immediately disables the crawling function; if the vehicle is already in crawling mode, it will forcibly exit crawling mode.

[0021] This embodiment incorporates the door status and driver presence status into the crawling pending recognition state judgment logic. When the door is opened or the driver leaves the seat, the vehicle exits the crawling state, thus preventing the vehicle from moving on its own due to misoperation, driver leaving the seat, or doors not being closed, etc.

[0022] In the creep waiting recognition state, the vehicle controller continuously monitors the accelerator pedal signal. When it detects that the accelerator pedal opening changes from greater than a preset threshold to less than or equal to zero opening, that is, the driver presses the accelerator and then releases it completely, the vehicle controller determines that the action is the driver's confirmation of the vehicle's intention to move and sets the internally stored creep capability latch flag to be valid.

[0023] This embodiment adds a recognition latch mechanism before creep, so that creep is no longer passively triggered by vehicle status, but requires the driver to perform a clear accelerator pedal action to express a genuine intention to move. The creep capability latch remains unchanged in scenarios such as braking, opening doors, and getting off the seat, which allows creep to be quickly resumed and avoids the burden of repeated confirmation by the driver.

[0024] When the crawl capability latch flag is enabled, the vehicle controller allows the activation of the crawl mode. At this time, the driver releases the brake pedal, and the vehicle controller activates the corresponding crawl mode according to the current vehicle gear information, including forward crawl mode or reverse crawl mode, wherein the forward crawl mode and reverse crawl mode are configured with different target vehicle speeds and parameters; If it is in D gear, the forward crawl mode is executed, the vehicle speed is set to the forward crawl target speed, for example, 5km / h, and the first set of PID control parameters is used. In this embodiment, the proportional coefficient P is 50 and the integral coefficient I is 5, and the torque response is faster at this time. If in R gear, reverse crawl mode is executed, the vehicle speed is set to the target reverse crawl speed, such as 3km / h, and the second set of PID control parameters is used. In this embodiment, the proportional coefficient P is selected as 40 and the integral coefficient I is 2. At this time, the torque response is smoother and reverse jerking is avoided.

[0025] The forward creep target speed is greater than the reverse creep target speed. The first set of PID control parameters includes a first proportional coefficient and a first integral coefficient, and the second set of PID control parameters includes a second proportional coefficient and a second integral coefficient. The first proportional coefficient is greater than the second proportional coefficient, and the first integral coefficient is greater than the second integral coefficient, so that the torque increment response speed during reverse creep is lower than the torque increment response speed during forward creep. In reverse creep mode, the vehicle controller is more sensitive to the brake pedal signal; that is, a light touch on the brake immediately disengages creep, adapting to the needs of frequent starts and stops and precise positioning during reverse.

[0026] This embodiment sets the target speed for reversing to be lower than that for forward creeping, and reduces the proportional coefficient and integral coefficient under reversing conditions, resulting in a slower torque increase and lower speed when reversing.

[0027] During the creeping process, the vehicle controller receives the current road gradient value in real time. Based on this gradient value, it calculates the feedforward compensation torque. The calculation method for the feedforward compensation torque is as follows: , in, Indicates feedforward compensation torque; θ Indicates the slope value; The sign indicates the direction of the slope; positive for uphill and negative for downhill. This refers to the compensation coefficient obtained or calculated based on the absolute value of the slope from a table. The absolute value of the slope table coefficient needs to be calibrated according to the specific vehicle model and working conditions. G This represents the gain estimated based on the total weight of the vehicle.

[0028] The final combined creep torque sent to the drive motor is: , in, This represents the final creep torque command value sent to the drive motor. This represents the base creep torque calculated by the PID algorithm based on the deviation between the current vehicle speed and the target vehicle speed. When the vehicle is preparing to start on a slope, the feedforward compensation torque... It provides additional positive torque to prevent the vehicle from rolling backward; when going downhill, the feedforward compensation torque is negative or regenerative braking is triggered to control the vehicle speed to keep it within limits.

[0029] In addition to PID parameter control, this embodiment introduces feedforward compensation for creep torque based on real-time slope information. When going uphill, the feedforward superimposed positive drive torque ensures that the vehicle receives sufficient anti-rollback torque the moment the brakes are released. When going downhill, the feedforward provides negative compensation to prevent excessive speed accumulation. This achieves anti-rollback during hill starts and adaptive downhill speed.

[0030] During crawl mode operation, the vehicle controller continuously monitors a preset set of exit conditions. These exit conditions include: the brake pedal being depressed, the driver's side door being opened, the driver exiting the seat, the handbrake being engaged, the gear being shifted to N or P, a charging signal being received, and the vehicle being powered off. When any of these conditions is detected, the vehicle controller immediately exits crawl mode.

[0031] If the exit conditions cause the creep waiting recognition state to fail (i.e., the handbrake is engaged, the gear is shifted to N or P, a charging signal is connected, or the vehicle is subjected to high voltage), the vehicle controller will simultaneously invalidate the creep capability latch flag. If the creep function is to be reactivated, the above waiting recognition process must be repeated.

[0032] When the brake pedal is pressed, the door is opened, or the driver leaves the seat, the crawl control is disengaged, but the crawl capability lock indicator remains unchanged. When the brake is released, the driver's side door is closed, the driver returns to the seat, and the brake pedal is not pressed, the crawl control can be reactivated without having to perform the crawl waiting recognition action again.

[0033] Example 2

[0034] This embodiment provides a crawl control device for a new energy heavy-duty truck, applied to a vehicle controller, including: The status management module is used to respond to vehicle power-on. When the vehicle is in the basic creep state, the doors are closed, and the driver is in the seat, it enters the creep waiting recognition state. The latch confirmation module is used to set the creep capability latch flag to an active state if it detects that the accelerator pedal has been pressed to a preset opening degree and then released and returned to zero opening degree when the creep waiting recognition state is in progress. The execution module is used to activate the corresponding creep mode according to the current vehicle gear information when the latching flag is valid. The creep mode includes forward creep mode and reverse creep mode. The compensation module is used to feedforward compensation of the creeping torque based on the real-time slope value during the creeping process; The exit module is used to exit the creep mode when any one of the exit conditions in the preset exit condition set is met. If the exit condition includes the creep basic state, the latch flag is set to an invalid state.

[0035] Example 3

[0036] This embodiment provides a new energy heavy-duty truck, including: The sensor array is used to collect data on accelerator pedal opening, brake pedal status, gear position, door status, driver presence signal, and road slope value. The vehicle controller is used to execute the creep control method for a new energy heavy-duty truck as described in any one of Embodiment 1.

[0037] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0038] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0039] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0040] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0041] The embodiments of the present invention have been described above with reference to the accompanying drawings. However, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of the present invention without departing from the spirit and scope of the claims. All of these forms are within the protection scope of the present invention.

[0042] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. A creep control method for a new energy heavy-duty truck, characterized in that, Includes the following steps: In response to the vehicle being powered on, determine whether the vehicle is currently in the basic creep state and whether the doors are closed and the driver is in the seat. If these conditions are met, enter the creep waiting recognition state. In the creep waiting recognition state, if it is detected that the accelerator pedal is pressed down to a preset opening degree and then released and returned to zero opening degree, the creep power latch flag is set to the valid state. When the creep driving capability latch flag is valid, the corresponding creep mode is activated according to the current vehicle gear information. The creep mode includes forward creep mode and reverse creep mode. During the creeping process, the creeping torque is fed forward to compensate based on the real-time slope value; When any one of the preset exit conditions is met, the creep mode is exited; wherein, if the exit condition includes the failure of the creep basic state, the creep power latch flag is set to an invalid state.

2. The creep control method for new energy heavy-duty trucks as described in claim 1, characterized in that, The criteria for determining whether a vehicle is in the aforementioned crawling basic state include: the handbrake is released, the gear is in D or R, the vehicle is connected to high voltage and there is no charging signal.

3. The creep control method for new energy heavy-duty trucks as described in claim 1, characterized in that, The forward crawling mode is characterized by setting the vehicle speed to the forward crawling target speed and using the first set of PID control parameters; the reverse crawling mode is characterized by setting the vehicle speed to the reverse crawling target speed and using the second set of PID control parameters.

4. The creep control method for new energy heavy-duty trucks as described in claim 3, characterized in that, The first set of PID control parameters includes a first proportional coefficient and a first integral coefficient, and the second set of PID control parameters includes a second proportional coefficient and a second integral coefficient; wherein the first proportional coefficient is greater than the second proportional coefficient, and the first integral coefficient is greater than the second integral coefficient, so that the forward creeping target speed is greater than the reverse creeping target speed.

5. The creep control method for new energy heavy-duty trucks as described in claim 1, characterized in that, The feedforward compensation of the creep torque is performed by superimposing the feedforward compensation torque with the base creep torque to obtain the comprehensive creep torque, wherein the comprehensive creep torque is: ， in, This indicates the combined creep torque command value. This represents the base creep torque calculated by the PID algorithm based on the deviation between the current vehicle speed and the target vehicle speed. This indicates the feedforward compensation torque.

6. The creep control method for new energy heavy-duty trucks as described in claim 5, characterized in that, The method for calculating the feedforward compensation torque is as follows: ， in, θ Indicates the slope value; The sign indicates the direction of the slope; positive for uphill and negative for downhill. This refers to the compensation coefficient obtained or calculated based on the absolute value of the slope from a table. The absolute value of the slope table coefficient needs to be calibrated according to the specific vehicle model and working conditions. G This represents the gain estimated based on the total weight of the vehicle.

7. The creep control method for new energy heavy-duty trucks as described in claim 1, characterized in that, The exit conditions include: the brake pedal is depressed, the driver's side door is opened, the driver leaves the seat, the handbrake is engaged, the gear is shifted to N or P, the charging signal is connected, and the vehicle is powered off.

8. A creep control device for a new energy heavy-duty truck, characterized in that, Applied to vehicle controllers, including: The status management module is used to respond to the vehicle power-on and determine whether the current vehicle is in the basic creep state and the doors are closed and the driver is in place. If these conditions are met, the vehicle enters the creep waiting recognition state. The latch confirmation module is used to set the creep capability latch flag to an active state if it detects that the accelerator pedal has been pressed to a preset opening degree and then released and returned to zero opening degree when the creep waiting recognition state is in progress. The execution module is used to activate the corresponding crawl mode according to the current vehicle gear information when the crawling capability latch flag is valid. The crawl mode includes forward crawl mode and reverse crawl mode. The compensation module is used to feedforward compensation of the creeping torque based on the real-time slope value during the creeping process; The exit module is used to exit the creep mode when any one of the exit conditions in the preset exit condition set is met. If the exit condition includes the creep basic state, the creep power latch flag is set to an invalid state.

9. A new energy heavy-duty truck, characterized in that, include: The sensor array is used to collect data on accelerator pedal opening, brake pedal status, gear position, door status, driver presence signal, and road slope value. A vehicle controller for executing the creep control method for a new energy heavy-duty truck as described in any one of claims 1-7.

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