Cruise Control Method, Electronic Device, Storage Medium and Program Product

Abstract

The present invention provides a cruise control method, electronic device, storage medium, and program product, relating to the field of cruise control algorithms. The method obtains the actual engine torque, actual vehicle speed, and target cruise speed of a vehicle, and calculates the required torque when the vehicle is traveling unloaded on a flat road at the target cruise speed based on reference vehicle characteristic parameters. The required torque is used as the static engine torque, and the dynamic engine torque is calculated based on the actual engine torque and actual vehicle speed. The actual vehicle speed and target cruise speed are input into a preset control algorithm to obtain a corrected engine torque. The total engine torque is determined based on the static engine torque, the dynamic engine torque, and the corrected engine torque, so that the vehicle's engine can be torque-controlled based on the total engine torque. This allows the vehicle to accurately provide engine output torque and stably control vehicle speed even when the vehicle mass changes significantly.

Description

Technical Field

[0001] The present application relates to the field of cruise control algorithms, and in particular to a cruise control method, electronic equipment, storage medium, and program product. Background Art

[0002] Cruise control or variable speed cruise control is a popular driver assistance system. This system adjusts engine torque based on changes in driving resistance to maintain a set speed. This reduces driving effort and improves safety during extended highway driving. It also minimizes unnecessary speed fluctuations and engine torque fluctuations, improving fuel economy.

[0003] In the existing technology, the Proportional Integral Differential (PID) algorithm calculates the vehicle speed error, the integral of the vehicle speed error, and the differential of the vehicle speed error, and then adjusts the engine torque based on the vehicle speed error, the integral of the vehicle speed error, and the differential of the vehicle speed error to achieve stable vehicle speed control.

[0004] However, the PID algorithm is based on a specific PID controller design and a mathematical model based on specific parameter adjustments. When the vehicle mass changes significantly, the PID algorithm cannot guarantee the robustness of its performance and cannot accurately provide the engine output torque, resulting in the inability to stably control the vehicle speed during cruise control. Summary of the Invention

[0005] Embodiments of the present application provide a cruise control method, electronic device, storage medium, and program product, which are used to accurately provide engine output torque and stably control vehicle speed even when the vehicle mass changes significantly.

[0006] In a first aspect, an embodiment of the present application provides a cruise control method, comprising:

[0007] Obtain the actual engine torque, actual vehicle speed, and target cruising speed of the vehicle at the current moment;

[0008] Based on the vehicle's reference vehicle characteristic parameters, the required torque when the vehicle is traveling at the target cruising speed and without load on a flat road is calculated as the static required torque of the engine;

[0009] Calculate the engine dynamic torque requirement based on the actual engine torque and the actual vehicle speed. The engine dynamic torque requirement includes: the torque caused by the current vehicle load, the torque caused by the current road gradient, and the torque error caused by the error between the actual vehicle characteristic parameters and the reference vehicle characteristic parameters;

[0010] The actual vehicle speed and the target cruising speed are input into a preset control algorithm to obtain the required torque for accelerating the vehicle from the actual vehicle speed to the target cruising speed as the corrected required torque of the engine;

[0011] The sum of the engine static demand torque, the engine dynamic demand torque and the engine correction demand torque is used as the engine total demand torque, so as to control the torque of the vehicle engine according to the engine total demand torque.

[0012] In one possible implementation, calculating the engine dynamic required torque based on the actual engine torque and the actual vehicle speed includes:

[0013] Initializing the engine's dynamic demand torque and inputting the actual engine torque into a torque-vehicle speed model to calculate an estimated vehicle speed. The torque-vehicle speed model is used to indicate the relationship between the estimated vehicle speed and the actual engine torque, the engine's dynamic demand torque, and reference vehicle characteristic parameters.

[0014] If the speed difference between the estimated vehicle speed and the actual vehicle speed does not meet the preset convergence condition, the engine dynamic demand torque in the torque-vehicle speed model is adjusted according to the speed difference until the speed difference between the estimated vehicle speed and the actual vehicle speed meets the preset convergence condition, and the engine dynamic demand torque is obtained.

[0015] In one possible implementation, adjusting the engine dynamic demand torque in the torque-vehicle speed model according to the vehicle speed difference includes:

[0016] Obtaining an adaptation rate, where the adaptation rate is used to indicate an adjustment amplitude and speed of a dynamic torque demand of an engine;

[0017] The engine's dynamic torque demand is adjusted based on the adaptation rate and vehicle speed difference.

[0018] In one possible embodiment, the reference vehicle characteristic parameters include: a reference vehicle unloaded mass, a reference rolling resistance coefficient, a reference air resistance coefficient, a reference frontal area, a reference rotational mass conversion coefficient, a reference gearbox transmission ratio, a reference final reducer transmission ratio, a reference transmission system mechanical efficiency, and a reference tire rolling radius.

[0019] In one possible implementation, the required torque of the vehicle when traveling unloaded at a target cruising speed on a flat road section is calculated based on reference vehicle characteristic parameters as the static required torque of the engine, including:

[0020] Calculate the static driving resistance based on the reference vehicle's unladen mass, reference rolling resistance coefficient, reference air resistance coefficient, reference frontal area, and target cruising speed. The static driving resistance is the sum of the static rolling resistance and the static air resistance. The static rolling resistance is the product of the reference vehicle's unladen mass, the reference rolling resistance coefficient, and the acceleration of gravity. The static air resistance is the product of a preset constant, the square of the target cruising speed, the reference air resistance coefficient, and the reference frontal area.

[0021] The engine static required torque is calculated based on the reference gearbox ratio, the reference final reducer ratio, the reference transmission system mechanical efficiency, the reference tire rolling radius and the static running resistance. The engine static required torque is the product of the static running resistance and the reference tire rolling radius, and the ratio of the reference gearbox ratio, the reference final reducer ratio and the reference transmission system mechanical efficiency.

[0022] In one possible implementation, the torque-vehicle speed model is:

[0023]

[0024] in, is the actual engine torque, is the reference gearbox ratio, is the reference final reducer transmission ratio, For the reference transmission system mechanical efficiency, is the reference tire rolling radius, is the reference vehicle unladen mass, is the reference rolling resistance coefficient, is the acceleration due to gravity, U is the estimated vehicle speed, is the reference air resistance coefficient, is the reference frontal area, is the reference rotating mass conversion factor, It is the change in driving resistance caused by changes in vehicle load, road slope, and the error between the reference vehicle characteristic parameters and the actual vehicle characteristic parameters.

[0025] In a second aspect, an embodiment of the present application provides a cruise control device, comprising:

[0026] An acquisition module is used to obtain the actual engine torque, actual vehicle speed, target cruising speed and reference vehicle characteristic parameters of the vehicle at the current moment;

[0027] a processing module for calculating, based on reference vehicle characteristic parameters, a required torque when the vehicle is traveling at a target cruising speed with no load on a flat road section, as a static required torque of the engine;

[0028] The processing module is further configured to calculate a dynamic engine torque requirement based on the actual engine torque and the actual vehicle speed, where the dynamic engine torque requirement includes: a torque caused by the current vehicle load, a torque caused by the current road gradient, and a torque error caused by an error between the actual vehicle characteristic parameters and the reference vehicle characteristic parameters;

[0029] The processing module is further configured to input the actual vehicle speed and the target cruising speed into a preset control algorithm to obtain a required torque for accelerating the vehicle from the actual vehicle speed to the target cruising speed as a corrected required torque for the engine;

[0030] The processing module is further configured to take the sum of the static engine demand torque, the dynamic engine demand torque and the corrected engine demand torque as the total engine demand torque, so as to perform torque control on the vehicle's engine according to the total engine demand torque.

[0031] In a cruise control device provided in an embodiment of the present application:

[0032] a processing module for initializing the engine's dynamic demand torque and inputting the engine's actual torque into a torque-vehicle speed model to calculate an estimated vehicle speed, wherein the torque-vehicle speed model is used to indicate a relationship between the estimated vehicle speed and the engine's actual torque, the engine's dynamic demand torque, and a reference vehicle characteristic parameter;

[0033] The processing module is also used to adjust the engine dynamic demand torque in the torque-vehicle speed model according to the vehicle speed difference when the vehicle speed difference between the estimated vehicle speed and the actual vehicle speed does not meet the preset convergence condition, until the engine dynamic demand torque is obtained when the vehicle speed difference between the estimated vehicle speed and the actual vehicle speed meets the preset convergence condition.

[0034] In a cruise control device provided in an embodiment of the present application:

[0035] An acquisition module, configured to acquire an adaptive rate, the adaptive rate being used to indicate an adjustment amplitude and speed of a dynamic torque demand of the engine;

[0036] The processing module is used to adjust the engine dynamic demand torque according to the adaptation rate and the vehicle speed difference.

[0037] In a cruise control device provided in an embodiment of the present application:

[0038] The acquisition module is used to obtain reference vehicle characteristic parameters, which include: reference vehicle unloaded mass, reference rolling resistance coefficient, reference air resistance coefficient, reference frontal area, reference rotational mass conversion coefficient, reference gearbox transmission ratio, reference final reducer transmission ratio, reference transmission system mechanical efficiency and reference tire rolling radius.

[0039] In a cruise control device provided in an embodiment of the present application:

[0040] a processing module for calculating a static running resistance based on a reference vehicle unladen mass, a reference rolling resistance coefficient, a reference air resistance coefficient, a reference frontal area, and a target cruising speed, where the static running resistance is the sum of the static rolling resistance and the static air resistance, the static rolling resistance is the product of the reference vehicle unladen mass, the reference rolling resistance coefficient, and the acceleration of gravity, and the static air resistance is the product of a preset constant, the square of the target cruising speed, the reference air resistance coefficient, and the reference frontal area;

[0041] The processing module is used to calculate the engine static demand torque based on the reference transmission ratio, the reference final reducer transmission ratio, the reference transmission system mechanical efficiency, the reference tire rolling radius and the static running resistance. The engine static demand torque is the product of the static running resistance and the reference tire rolling radius and the ratio of the reference transmission ratio, the reference final reducer transmission ratio and the reference transmission system mechanical efficiency.

[0042] In a cruise control device provided in an embodiment of the present application:

[0043] The acquisition module is used to obtain the torque-vehicle speed model. The torque-vehicle speed model is:

[0044]

[0045] in, is the actual engine torque, is the reference gearbox ratio, is the reference final reducer transmission ratio, For the reference transmission system mechanical efficiency, is the reference tire rolling radius, is the reference vehicle unladen mass, is the reference rolling resistance coefficient, is the acceleration due to gravity, U is the estimated vehicle speed, is the reference air resistance coefficient, is the reference frontal area, is the reference rotating mass conversion factor, It is the change in driving resistance caused by changes in vehicle load, road slope, and the error between the reference vehicle characteristic parameters and the actual vehicle characteristic parameters.

[0046] In a third aspect, an embodiment of the present application provides an electronic device, including: a memory, a processor;

[0047] Memory stores computer-executable instructions;

[0048] The processor executes the computer-executable instructions stored in the memory, so that the processor executes the above first aspect and / or various possible implementations of the first aspect.

[0049] In a fourth aspect, an embodiment of the present application provides a computer-readable storage medium, in which computer-executable instructions are stored. When the computer-executable instructions are executed by a processor, they are used to implement the first aspect above and / or various possible implementation methods of the first aspect.

[0050] In a fifth aspect, an embodiment of the present application provides a computer program product, including a computer program, which, when executed by a processor, implements the above first aspect and / or various possible implementation methods of the first aspect.

[0051] The embodiments of the present application provide a cruise control method, electronic device, storage medium, and program product. The method obtains the actual engine torque, actual vehicle speed, and target cruise speed of a vehicle at a current moment, and then calculates the required torque of the vehicle when it is traveling unloaded on a flat road section at the target cruise speed based on the reference vehicle characteristic parameters. The torque is used as the static required torque of the engine. The dynamic required torque of the engine is calculated based on the actual engine torque and the actual vehicle speed. The actual vehicle speed and the target cruise speed are input into a preset control algorithm to obtain the required torque for accelerating the vehicle from the actual vehicle speed to the target cruise speed. The torque is used as the corrected required torque of the engine. Finally, the total required torque of the engine is determined based on the static required torque of the engine, the dynamic required torque of the engine, and the corrected required torque of the engine, so as to perform torque control on the vehicle's engine based on the total required torque of the engine. Compared with the prior art in which the PID algorithm is used to adjust the engine torque, the performance of the PID algorithm will deteriorate due to the large change in vehicle mass, and thus it will be unable to provide accurate engine output torque, which ultimately leads to the inability to stably control the vehicle speed. The present application first calculates the static required torque of the vehicle when it is traveling unloaded on a flat road section based on the vehicle's reference vehicle characteristic parameters and the target cruising speed. Then, based on the actual engine torque, actual vehicle speed and reference vehicle characteristic parameters, combined with the torque-speed model, the dynamic required torque of the vehicle is calculated. The dynamic required torque fully considers the torque caused by the vehicle's current load, the torque caused by the current road slope, and the torque error caused by the error between the vehicle's actual vehicle characteristic parameters and the reference vehicle characteristic parameters. Then, the torque required for the vehicle to accelerate from the actual speed to the target cruising speed is calculated as the engine corrected required torque. Based on the static required torque and the dynamic required torque, the corrected required torque is combined for control, thereby obtaining more accurate torque control, and thus being able to stably control the vehicle speed during cruising. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0053] Figure 1 A schematic diagram of a cruise control method provided in this application;

[0054] Figure 2 A flowchart of a cruise control method according to embodiment 1 of the present application;

[0055] Figure 3 A schematic flow chart of a second embodiment of a cruise control method provided by this application;

[0056] Figure 4 A flowchart of a cruise control method embodiment 3 provided in this application;

[0057] Figure 5 A flowchart of a fourth embodiment of a cruise control method provided by this application;

[0058] Figure 6 A schematic diagram of the structure of the cruise control device provided in this application;

[0059] Figure 7 This is a schematic diagram of the structure of the electronic device provided in this application.

[0060] The above drawings illustrate specific embodiments of the present application, which will be described in more detail below. These drawings and the textual description are not intended to limit the scope of the present application in any way, but rather to illustrate the concepts of the present application to those skilled in the art by reference to specific embodiments. DETAILED DESCRIPTION

[0061] Exemplary embodiments will be described in detail herein, with examples illustrated in the accompanying drawings. In the following description, when referring to the drawings, identical numerals in different figures represent identical or similar elements, unless otherwise indicated. The embodiments described in the following exemplary embodiments are not intended to represent all embodiments consistent with the present application. Rather, they are merely examples of apparatus and methods consistent with certain aspects of the present application, as detailed in the appended claims.

[0062] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, stored data, displayed data, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, storage, use, processing, transmission, provision, disclosure and application of the relevant data comply with the relevant laws, regulations and standards of the relevant countries and regions, take necessary confidentiality measures, do not violate public order and good morals, and provide corresponding operation entrances for users to choose to authorize or refuse.

[0063] In existing technology, heavy-duty tractors have a wide range of mass variations. For example, the gross weight of a tractor is 9.5 tons (tons, t), but when equipped with a fully loaded trailer, the total mass can reach 55 tons. However, the PID algorithm is based on a specific PID controller design and a mathematical model based on specific parameter adjustments. When the vehicle mass varies significantly, the PID algorithm cannot fully reflect the dynamic characteristics of the actual physical system, and therefore cannot accurately output engine torque, resulting in the inability to stabilize the vehicle speed during cruise control.

[0064] Based on this, the inventive concept of this application is to provide a cruise control method that can still accurately provide engine torque when the vehicle mass range varies greatly. Therefore, this application calculates the static demand torque and dynamic demand torque, and combines the engine corrected demand torque to obtain the total demand torque of the engine. The engine static demand torque is the engine torque required to maintain the target cruising speed when the vehicle is unloaded on a flat road, and the engine dynamic demand torque is the torque caused by the current load of the vehicle, the torque caused by the current road slope, and the torque error caused by the error between the actual vehicle characteristic parameters and the reference vehicle characteristic parameters. Therefore, based on the engine dynamic demand torque and the engine static demand torque, the engine corrected demand torque is combined for correction, so that the engine can be provided with accurate output torque, thereby stably controlling the vehicle speed during cruise control.

[0065] Figure 1 A schematic diagram of a cruise control method provided in this application, such as Figure 1As shown, the engine management system outputs the actual torque of the vehicle engine, the dynamic demand torque calculation module calculates the engine dynamic demand torque according to the actual engine torque and the actual vehicle speed, the static demand torque calculation module calculates the engine static demand torque according to the target cruising speed, and the engine correction demand torque calculation module inputs the actual vehicle speed and the target cruising speed into the preset control algorithm to obtain the engine correction demand torque. Then the microprocessor determines the total engine demand torque according to the engine dynamic demand torque, the engine static demand torque and the engine correction demand torque, and sends it to the engine management system to perform torque control on the vehicle's engine.

[0066] The following specific embodiments describe in detail the technical solution of the present application and how the technical solution of the present application solves the above-mentioned technical problems. The following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be repeated in some embodiments. The embodiments of the present application will be described below in conjunction with the accompanying drawings.

[0067] Figure 2 This is a flow chart of a cruise control method embodiment 1 provided in this application, such as Figure 1 As shown, the method includes the following steps:

[0068] S201: Obtain the actual engine torque, actual vehicle speed, and target cruising speed of the vehicle at the current moment.

[0069] In this embodiment of the present application, the actual engine torque, actual vehicle speed, and target cruising speed of the vehicle at the current moment are obtained. The target cruising speed is the desired speed set by the driver. The actual vehicle speed must be controlled to be close to the target cruising speed.

[0070] S202: Calculate the required torque of the vehicle when it is traveling at a target cruising speed and without load on a flat road section based on reference vehicle characteristic parameters, as the static required torque of the engine.

[0071] In an embodiment of the present application, based on the reference vehicle characteristic parameters, the required torque when the vehicle is traveling idly at a target cruising speed on a flat road section is calculated as the static required torque of the engine.

[0072] The reference vehicle characteristic parameters are reference values of the vehicle characteristic parameters. Usually, the reference vehicle characteristic parameters can be the design values when the vehicle leaves the factory. During the actual use of the vehicle, the reference vehicle characteristic parameters will have an actual value, called the actual vehicle characteristic parameters. The actual vehicle characteristic parameters usually have a certain deviation from the reference vehicle characteristic parameters. For example, the reference tire rolling radius will deviate from the tire rolling radius when the vehicle leaves the factory due to the unevenness and wear of the vehicle tires and the influence of tire pressure; the reference rolling resistance coefficient is related to the type of road surface, the vehicle's driving speed, and the structure, material, and air pressure of the vehicle tires, and therefore deviates from the rolling resistance coefficient set at the factory.

[0073] In some embodiments, the reference vehicle characteristic parameters include: a reference vehicle unladen mass, a reference rolling resistance coefficient, a reference air resistance coefficient, a reference frontal area, a reference rotational mass conversion factor, a reference transmission ratio, a reference final drive ratio, a reference drivetrain mechanical efficiency, and a reference tire rolling radius. Accordingly, the actual vehicle characteristic parameters include: an actual vehicle unladen mass, an actual rolling resistance coefficient, an actual air resistance coefficient, an actual frontal area, an actual rotational mass conversion factor, an actual transmission ratio, an actual final drive ratio, an actual drivetrain mechanical efficiency, and an actual tire rolling radius.

[0074] It should be noted that since the reference gearbox transmission ratio and the reference final reducer transmission ratio are the same as the actual gearbox transmission ratio and the actual final reducer transmission ratio during vehicle use, the reference gearbox transmission ratio and the reference final reducer transmission ratio mentioned in this application are the actual gearbox transmission ratio and the actual final reducer transmission ratio.

[0075] S203: Calculate the engine dynamic required torque according to the actual engine torque and the actual vehicle speed.

[0076] In an embodiment of the present application, the engine dynamic required torque is calculated based on the actual engine torque and the actual vehicle speed, wherein the engine dynamic required torque includes: the torque caused by the current load of the vehicle, the torque caused by the current road slope, and the torque error caused by the error between the actual vehicle characteristic parameters of the vehicle and the reference vehicle characteristic parameters.

[0077] S204: Input the actual vehicle speed and the target cruising speed into a preset control algorithm to obtain the required torque for accelerating the vehicle from the actual vehicle speed to the target cruising speed as the corrected required torque of the engine.

[0078] In the embodiment of the present application, the actual vehicle speed and the target cruising speed are input into a preset control algorithm to obtain the required torque for accelerating the vehicle from the actual vehicle speed to the target cruising speed, which is used as the corrected required torque of the engine. Optionally, the preset control algorithm is a PID algorithm.

[0079] S205: Taking the sum of the engine static demand torque, the engine dynamic demand torque and the engine correction demand torque as the engine total demand torque, so as to perform torque control on the vehicle engine according to the engine total demand torque.

[0080] In an embodiment of the present application, the sum of the engine's static demand torque, the engine's dynamic demand torque and the engine's corrected demand torque is taken as the engine's total demand torque. The engine's total demand torque comprehensively considers static conditions, dynamic changes and control strategies, and can accurately reflect the actual demands of the engine under the current driving state. The vehicle's engine is torque controlled according to the engine's total demand torque.

[0081] In an embodiment of the present application, the actual engine torque, actual vehicle speed and target cruising speed of the vehicle at the current moment are obtained, and then the required torque of the vehicle when it is traveling idly on a flat road section at the target cruising speed is calculated based on the reference vehicle characteristic parameters of the vehicle, as the static required torque of the engine. The dynamic required torque of the engine is calculated based on the actual engine torque and the actual vehicle speed. The actual vehicle speed and the target cruising speed are input into a preset control algorithm to obtain the required torque for accelerating the vehicle from the actual speed to the target cruising speed as the corrected required torque of the engine. Finally, the sum of the static required torque of the engine, the dynamic required torque of the engine and the corrected required torque of the engine is used as the total required torque of the engine to perform torque control on the vehicle's engine based on the total required torque of the engine. Compared to the prior art method of using a PID algorithm to adjust engine torque, where significant changes in vehicle mass can cause the PID algorithm's performance to degrade, leading to an inability to provide accurate engine output torque and ultimately an inability to stably control vehicle speed, the present application calculates the engine torque required to maintain a target cruising speed on a level road when unloaded based on reference vehicle characteristic parameters. This calculation serves as the static engine torque requirement. The dynamic engine torque requirement is then calculated based on the actual engine torque and the actual vehicle speed. The dynamic engine torque requirement fully accounts for the torque caused by the vehicle's current load, the torque caused by the current road slope, and the torque error caused by the error between the actual vehicle characteristic parameters and the reference vehicle characteristic parameters. The actual vehicle speed and the target cruising speed are then input into a preset control algorithm to obtain a corrected engine torque requirement. The corrected engine torque requirement is then added to the calculated static and dynamic engine torque requirements to ensure accurate engine output torque is provided under all road and vehicle conditions, thereby enabling stable vehicle speed control during cruise control.

[0082] Figure 3 This is a flow chart of a cruise control method embodiment 2 provided in this application. Figure 2 Based on the embodiment shown, a specific implementation of step S203 is as follows:

[0083] S301: Initialize the engine dynamic required torque, and input the engine actual torque into a torque-vehicle speed model to calculate and obtain an estimated vehicle speed.

[0084] In the embodiment of the present application, the torque-vehicle speed model is modified based on the driving force-travel resistance balance model, wherein the driving force-travel resistance balance model is:

[0085]

[0086] in, is the actual engine torque, is the gearbox ratio, is the main reducer transmission ratio, is the mechanical efficiency of the transmission system, is the tire rolling radius, is the vehicle mass, is the acceleration due to gravity, is the road slope, is the rolling resistance coefficient, is the air resistance coefficient, is the windward area, is the vehicle speed, is the rotational mass conversion factor.

[0087] While the vehicle is cruising, Can be used as a known quantity, so the main factor that determines the change in driving resistance is the vehicle mass and road slope , then the vehicle mass is set as the reference vehicle unladen mass, and the road slope Set it to 0, and then add the driving resistance change value caused by vehicle load change, road slope change, and driving resistance calculation parameter error into the driving force-driving resistance balance model. The modified driving force-driving resistance balance model is:

[0088]

[0089] in, is the actual engine torque, is the reference gearbox ratio, is the reference final reducer transmission ratio, For the reference transmission system mechanical efficiency, is the reference tire rolling radius, is the reference vehicle unladen mass, is the reference rolling resistance coefficient, is the acceleration due to gravity, U is the estimated vehicle speed, is the air resistance coefficient, is the reference frontal area, is the reference rotating mass conversion factor, The driving resistance change value caused by changes in vehicle load, road slope, and driving resistance calculation parameter errors.

[0090] Then replace the above formula (2) with 、 、 、 Transforming the right side of formula (2) yields the torque-vehicle speed model:

[0091]

[0092] in, is the engine dynamic torque requirement, is the actual engine torque, is the reference gearbox ratio, is the reference final reducer transmission ratio, For the reference transmission system mechanical efficiency, is the reference tire rolling radius, is the reference vehicle unladen mass, is the reference rolling resistance coefficient, is the acceleration due to gravity, U is the estimated vehicle speed, is the reference air resistance coefficient, is the reference frontal area, is the reference rotating mass conversion factor, The driving resistance change value caused by changes in vehicle load, road slope, and driving resistance calculation parameter errors.

[0093] It should be noted that the actual engine torque is used as the value to initialize the dynamic engine demand torque and input into the torque-vehicle speed model. and is an unknown number, so The estimated vehicle speed can be calculated .

[0094] S302: If the speed difference between the estimated vehicle speed and the actual vehicle speed does not meet the preset convergence condition, the engine dynamic demand torque in the torque-vehicle speed model is adjusted according to the speed difference until the speed difference between the estimated vehicle speed and the actual vehicle speed meets the preset convergence condition, and the engine dynamic demand torque is obtained.

[0095] In an embodiment of the present application, if the speed difference between the estimated vehicle speed and the actual vehicle speed does not meet the preset convergence condition, that is, the estimated vehicle speed and the actual vehicle speed differ greatly, if the speed difference does not meet the preset convergence condition, it means that the current engine dynamic demand torque needs to be adjusted to better match the actual demand. At this time, the engine dynamic demand torque in the torque-vehicle speed model is adjusted according to the speed difference until the speed difference between the estimated vehicle speed and the actual vehicle speed meets the preset convergence condition, and the engine dynamic demand torque is obtained.

[0096] The convergence condition may be that the vehicle speed difference becomes smaller and smaller, and / or the vehicle speed difference is less than or equal to a preset vehicle speed difference.

[0097] In an embodiment of the present application, the engine dynamic demand torque is initialized, and the actual engine torque is input into the torque-vehicle speed model for calculation to obtain the estimated vehicle speed. If the speed difference between the estimated vehicle speed and the actual vehicle speed does not meet the preset convergence condition, the engine dynamic demand torque in the torque-vehicle speed model is adjusted according to the speed difference until the speed difference between the estimated vehicle speed and the actual vehicle speed meets the preset convergence condition, and the engine dynamic demand torque is obtained. The engine dynamic demand torque fully considers the torque caused by the current load to ensure the vehicle's power performance, fully considers the torque caused by the road slope, and can provide greater torque to overcome gravity when going uphill, and provide smaller torque to prevent the vehicle from speeding when going downhill, and fully considers the torque error caused by the error between the actual vehicle characteristic parameters of the vehicle and the reference vehicle characteristic parameters, so as to make corresponding corrections to the engine demand torque to improve the accuracy of torque control.

[0098] Figure 4 This is a flow chart of a cruise control method embodiment 3 provided in this application. Figure 3 Based on the embodiment shown, a specific implementation of adjusting the engine dynamic demand torque in the torque-vehicle speed model according to the vehicle speed difference in step S302 is as follows:

[0099] S401: Acquire an adaptive rate, where the adaptive rate is used to indicate an adjustment range and speed of the engine's dynamic torque requirement.

[0100] In the embodiment of the present application, the reasonable design of the adaptive rate can make the estimated parameters converge accurately to the true value. The adaptive rate is designed by Lyapunov stability theory to ensure the stability of the estimation system. Through reasonable theoretical deduction, the adaptive rate is selected as the Proportion Integral (PI) adaptation rate.

[0101] S402: Adjust the engine dynamic torque requirement according to the adaptation rate and the vehicle speed difference.

[0102] In an embodiment of the present application, the engine dynamic demand torque is adjusted according to the adaptation rate and the vehicle speed difference. Specifically, the difference between the actual vehicle speed and the estimated vehicle speed is calculated. If the vehicle speed difference does not meet the convergence condition, the engine dynamic demand torque is adjusted. Optionally, the adjustment amount is the vehicle speed difference multiplied by the proportional coefficient plus the integral of the vehicle speed difference multiplied by the integral coefficient. The calculated adjustment amount is added to the current engine dynamic demand torque to obtain a new engine dynamic demand torque. The new engine dynamic demand torque is input into the torque-vehicle speed model again to obtain a new estimated vehicle speed. The difference between the new estimated vehicle speed and the actual vehicle speed is compared. If the vehicle speed difference still does not meet the convergence condition, the engine dynamic demand torque continues to be adjusted. This process is repeated until the vehicle speed difference meets the preset convergence condition. The final result is the accurate dynamic demand torque.

[0103] In an embodiment of the present application, an adaptive rate is obtained, and the adaptive rate is used to indicate the adjustment amplitude and speed of the engine dynamic demand torque, so as to adjust the engine dynamic demand torque according to the adaptive rate and the vehicle speed difference. Through the adaptive rate, the adjustment amplitude and speed of the engine dynamic demand torque can be accurately controlled to obtain accurate engine dynamic demand torque.

[0104] Figure 5 This is a flow chart of a cruise control method embodiment 4 provided in this application. Figures 2 to 4 Based on the embodiment shown, a specific implementation of step S202 is as follows:

[0105] S501: Calculate static driving resistance based on a reference vehicle unladen mass, a reference rolling resistance coefficient, a reference air resistance coefficient, a reference frontal area, and a target cruising speed.

[0106] In the embodiment of the present application, the static driving resistance is the sum of the static rolling resistance and the static air resistance.

[0107] The static rolling resistance is the product of the reference vehicle's unloaded mass, the reference rolling resistance coefficient, and the acceleration of gravity. The calculation formula is:

[0108]

[0109] in, is the static rolling resistance, is the reference vehicle unladen mass, is the reference rolling resistance coefficient, is the acceleration due to gravity.

[0110] Static air resistance is the product of a preset constant, the square of the target cruising speed, the reference air resistance coefficient, and the reference frontal area. The calculation formula is:

[0111]

[0112] in, is the static air resistance, is the target cruising speed, is the reference air resistance coefficient, is the reference frontal area.

[0113] S502: Calculate the engine static required torque according to a reference transmission ratio, a reference final drive ratio, a reference transmission system mechanical efficiency, a reference tire rolling radius, and a static running resistance.

[0114] In the embodiment of the present application, the static required torque of the engine is the product of the static running resistance, the reference tire rolling radius, the reference gearbox transmission ratio, the reference final drive transmission ratio, and the reference transmission system mechanical efficiency. The calculation formula is:

[0115]

[0116] in, is the static torque demanded by the engine, is the reference gearbox ratio, is the reference final reducer transmission ratio, For the reference transmission system mechanical efficiency, is the reference tire rolling radius.

[0117] In an embodiment of the present application, the static driving resistance is calculated based on the reference vehicle unloaded mass, the reference rolling resistance coefficient, the reference air resistance coefficient, the reference frontal area and the target cruising speed. The static required torque of the engine is calculated based on the reference gearbox transmission ratio, the reference final reducer transmission ratio, the reference transmission system mechanical efficiency, the reference tire rolling radius and the static driving resistance. By accurately calculating the static rolling resistance and the static air resistance, the static required torque of the engine is obtained based on the static rolling resistance and the static air resistance, which provides an accurate calculation basis for the subsequent calculation of the total required torque of the engine.

[0118] Figure 6 A schematic diagram of the structure of the cruise control device provided in this application is shown in FIG. Figure 6 As shown, the cruise control device provided in this embodiment includes:

[0119] An acquisition module 601 is used to obtain the actual engine torque, actual vehicle speed, target cruising speed, and reference vehicle characteristic parameters of the vehicle at the current moment; a processing module 602 is used to calculate, based on the reference vehicle characteristic parameters, the required torque of the vehicle when traveling unloaded on a flat road section at the target cruising speed, as the static required torque of the engine; the processing module 602 is also used to calculate the dynamic required torque of the engine based on the actual engine torque and the actual vehicle speed, where the dynamic required torque of the engine includes: the torque caused by the current load of the vehicle, the torque caused by the current road slope, and the torque error caused by the error between the actual vehicle characteristic parameters of the vehicle and the reference vehicle characteristic parameters; the processing module 602 is also used to input the actual vehicle speed and the target cruising speed into a preset control algorithm to obtain the required torque for accelerating the vehicle from the actual vehicle speed to the target cruising speed, as the corrected required torque of the engine; the processing module 602 is also used to determine the total required torque of the engine based on the static required torque of the engine, the dynamic required torque of the engine, and the corrected required torque of the engine, so as to perform torque control on the vehicle's engine according to the total required torque of the engine.

[0120] The cruise control device provided in this embodiment can execute the method provided in the above method embodiment. Its implementation principle and technical effects are similar and will not be described in detail in this embodiment.

[0121] Figure 7 This is a schematic diagram of the structure of the electronic device provided in this application. Figure 7 As shown, the electronic device provided in this embodiment includes: at least one processor 701 and a memory 702. Optionally, the device further includes a communication component 703. The processor 701, the memory 702 and the communication component 703 are connected via a bus 704.

[0122] During the specific implementation process, at least one processor 701 executes the computer-executable instructions stored in the memory 702, so that the at least one processor 701 performs the above method.

[0123] The specific implementation process of the processor 701 can be found in the above method embodiment. Its implementation principle and technical effects are similar and will not be repeated here in this embodiment.

[0124] In the above embodiments, it should be understood that the processor may be a central processing unit (CPU), other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASICs), etc. A general-purpose processor may be a microprocessor or any conventional processor. The steps of the method disclosed in the present invention may be directly executed by a hardware processor or by a combination of hardware and software modules within the processor.

[0125] The memory may include random access memory (RAM) and may also include non-volatile memory (NVM), such as at least one disk storage.

[0126] A bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus. Buses can be categorized as address buses, data buses, and control buses. For ease of illustration, the buses in the drawings of this application are not limited to just one bus or just one type of bus.

[0127] The present application also provides a computer program product, including a computer program, which implements the above method when executed by a processor.

[0128] The present application also provides a computer-readable storage medium, in which computer-executable instructions are stored. When a processor executes the computer-executable instructions, the above method is implemented.

[0129] The readable storage medium may be implemented by any type of volatile or non-volatile memory device, or a combination thereof, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic storage, flash memory, magnetic disk, or optical disk. The readable storage medium may be any available medium that can be accessed by a general-purpose or special-purpose computer.

[0130] An exemplary readable storage medium is coupled to a processor so that the processor can read information from the readable storage medium and write information to the readable storage medium. Of course, the readable storage medium can also be an integral part of the processor. The processor and the readable storage medium can be located in an application specific integrated circuit (ASIC). Of course, the processor and the readable storage medium can also exist in the device as discrete components.

[0131] The division of units is merely a logical functional division; actual implementations may employ alternative divisions, such as combining or integrating multiple units or components into another system, or omitting or disabling certain features. Furthermore, any direct coupling or communication connection shown or discussed may be an indirect coupling or communication connection between devices or units, either through an interface, electrical, mechanical, or other means.

[0132] Units described as separate components may or may not be physically separate, and components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of these units may be selected to achieve the purpose of this embodiment according to actual needs.

[0133] In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0134] If a function is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the portion that contributes to the prior art, or a portion 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 for causing a computer device (which can be a personal computer, server, or network device, etc.) to execute all or part of the steps of the various embodiments of the method of the present invention. The aforementioned storage medium includes various media that can store program code, such as USB flash drives, mobile hard drives, read-only memories (ROMs), random access memories (RAMs), magnetic disks, or optical disks.

[0135] Those skilled in the art will appreciate that all or part of the steps in the above-described method embodiments can be implemented using hardware associated with program instructions. The aforementioned program can be stored in a computer-readable storage medium. When executed, the program performs the steps of the above-described method embodiments. The aforementioned storage medium includes various media capable of storing program code, such as ROM, RAM, magnetic disks, or optical disks.

[0136] Finally, it should be noted that those skilled in the art will readily identify other embodiments of the present invention after considering the specification and practicing the invention disclosed herein. The present invention is intended to cover any variations, uses, or adaptations of the present invention that follow the general principles of the present invention and include common knowledge or customary techniques in the art not disclosed herein. The present invention is not limited to the precise structure described above and illustrated in the accompanying drawings, and various modifications and variations may be made without departing from the scope thereof. The scope of the present invention is limited solely by the appended claims.

Claims

1. A cruise control method, characterized in that: include: Obtain the actual engine torque, actual vehicle speed, and target cruising speed of the vehicle at the current moment; Calculating, based on reference vehicle characteristic parameters of the vehicle, a required torque when the vehicle is traveling unloaded on a flat road section at the target cruising speed as the engine static required torque; wherein the reference vehicle characteristic parameters are reference values of the vehicle characteristic parameters; Calculating a dynamic engine torque requirement based on the actual engine torque and the actual vehicle speed, the dynamic engine torque requirement including: a torque caused by a current load of the vehicle, a torque caused by a current road gradient, and a torque error caused by an error between an actual vehicle characteristic parameter of the vehicle and a reference vehicle characteristic parameter; Inputting the actual vehicle speed and the target cruising speed into a preset control algorithm to obtain a required torque for accelerating the vehicle from the actual vehicle speed to the target cruising speed as a corrected required torque of the engine; taking the sum of the static engine demand torque, the dynamic engine demand torque and the corrected engine demand torque as a total engine demand torque, so as to perform torque control on the engine of the vehicle according to the total engine demand torque; The calculating the engine dynamic required torque according to the actual engine torque and the actual vehicle speed includes: Initializing the engine dynamic demand torque and inputting the actual engine torque into a torque-vehicle speed model to calculate an estimated vehicle speed, wherein the torque-vehicle speed model is used to indicate the relationship between the estimated vehicle speed and the actual engine torque, the engine dynamic demand torque, and the reference vehicle characteristic parameter; if the speed difference between the estimated vehicle speed and the actual vehicle speed does not meet a preset convergence condition, adjusting the engine dynamic demand torque in the torque-vehicle speed model according to the speed difference until the speed difference between the estimated vehicle speed and the actual vehicle speed meets the preset convergence condition, thereby obtaining the engine dynamic demand torque; wherein the preset convergence condition is that the speed difference is less than or equal to a preset speed difference; The adjusting of the engine dynamic demand torque in the torque-vehicle speed model according to the vehicle speed difference includes: obtaining an adaptation rate, wherein the adaptation rate is used to indicate the adjustment amplitude and speed of the engine dynamic demand torque; and adjusting the engine dynamic demand torque according to the adaptation rate and the vehicle speed difference.

2. The method according to claim 1, characterized in that The reference vehicle characteristic parameters include: reference vehicle unloaded mass, reference rolling resistance coefficient, reference air resistance coefficient, reference frontal area, reference rotational mass conversion coefficient, reference gearbox transmission ratio, reference final reducer transmission ratio, reference transmission system mechanical efficiency and reference tire rolling radius.

3. The method according to claim 2, characterized in that The step of calculating, based on the reference vehicle characteristic parameters, the required torque when the vehicle is traveling unloaded on a flat road section at the target cruising speed as the static required torque of the engine includes: Calculating a static driving resistance based on the reference vehicle unloaded mass, a reference rolling resistance coefficient, a reference air resistance coefficient, a reference frontal area, and the target cruising speed, wherein the static driving resistance is the sum of the static rolling resistance and the static air resistance, the static rolling resistance is the product of the reference vehicle unloaded mass, the reference rolling resistance coefficient, and the acceleration of gravity, and the static air resistance is the product of a preset constant, the square of the target cruising speed, the reference air resistance coefficient, and the reference frontal area; The engine static required torque is calculated based on the reference transmission ratio, reference final reducer ratio, reference transmission system mechanical efficiency, reference tire rolling radius and the static driving resistance corresponding to the current gear. The engine static required torque is the product of the static driving resistance and the reference tire rolling radius and the ratio of the reference transmission ratio, reference final reducer ratio and reference transmission system mechanical efficiency.

4. The method according to claim 1, wherein The torque-vehicle speed model is: in, is the engine dynamic torque requirement, is the actual engine torque, is the reference gearbox ratio, is the reference final reducer transmission ratio, For the reference transmission system mechanical efficiency, is the reference tire rolling radius, is the reference vehicle unladen mass, is the reference rolling resistance coefficient, is the acceleration due to gravity, U is the estimated vehicle speed, is the reference air resistance coefficient, is the reference frontal area, is the reference rotating mass conversion factor, It is the change in driving resistance caused by changes in vehicle load, road slope, and the error between the reference vehicle characteristic parameters and the actual vehicle characteristic parameters.

5. A cruise control device, characterized in that: include: An acquisition module is used to obtain the actual engine torque, actual vehicle speed, target cruising speed and reference vehicle characteristic parameters of the vehicle at the current moment; a processing module, configured to calculate, based on reference vehicle characteristic parameters of the vehicle, a required torque when the vehicle is traveling unloaded on a flat road section at the target cruising speed, as a static required torque of the engine; wherein the reference vehicle characteristic parameters are reference values of the vehicle characteristic parameters; The processing module is further configured to calculate a dynamic engine torque requirement based on the actual engine torque and the actual vehicle speed, wherein the dynamic engine torque requirement includes: a torque caused by a current load of the vehicle, a torque caused by a current road gradient, and a torque error caused by an error between an actual vehicle characteristic parameter of the vehicle and a reference vehicle characteristic parameter; The processing module is further configured to input the actual vehicle speed and the target cruising speed into a preset control algorithm to obtain a required torque for accelerating the vehicle from the actual vehicle speed to the target cruising speed as a corrected required torque of the engine; The processing module is further configured to determine a total engine demand torque based on the engine static demand torque, the engine dynamic demand torque, and the engine corrected demand torque, so as to perform torque control on the vehicle engine based on the total engine demand torque; The processing module, when calculating the engine dynamic demand torque based on the engine actual torque and the actual vehicle speed, is specifically configured to: initialize the engine dynamic demand torque, and input the engine actual torque into a torque-vehicle speed model to calculate an estimated vehicle speed, wherein the torque-vehicle speed model is configured to indicate a relationship between the estimated vehicle speed and the engine actual torque, the engine dynamic demand torque, and the reference vehicle characteristic parameter; If the speed difference between the estimated vehicle speed and the actual vehicle speed does not meet the preset convergence condition, the engine dynamic demand torque in the torque-vehicle speed model is adjusted according to the speed difference until the speed difference between the estimated vehicle speed and the actual vehicle speed meets the preset convergence condition, and the engine dynamic demand torque is obtained; wherein, the preset convergence condition is that the speed difference is less than or equal to the preset speed difference; wherein, adjusting the engine dynamic demand torque in the torque-vehicle speed model according to the speed difference includes: obtaining an adaptive rate, the adaptive rate is used to indicate the adjustment amplitude and speed of the engine dynamic demand torque; adjusting the engine dynamic demand torque according to the adaptive rate and the speed difference.

6. An electronic device, characterized in that: include: Memory, processor; The memory stores computer-executable instructions; The processor executes the computer-executable instructions stored in the memory, so that the processor performs the method according to any one of claims 1 to 4.

7. A computer-readable storage medium, characterized in that The computer-readable storage medium stores computer-executable instructions, which are used to implement the method according to any one of claims 1 to 4 when executed by a processor.

8. A computer program product, characterized in that The invention comprises a computer program, which implements the method according to any one of claims 1 to 4 when executed by a processor.

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