Cruise control method, electronic device, storage medium and program product

Abstract

The embodiment of the invention provides a cruise control method, electronic equipment, a storage medium and a program product, and relates to the field of cruise control algorithms. The actual engine torque, the actual vehicle speed and the target cruise vehicle speed of the vehicle are obtained, the required torque when the vehicle runs on the level road section at the target cruise vehicle speed in a no-load mode is calculated according to the reference whole vehicle characteristic parameters of the vehicle and serves as the static engine required torque, and the dynamic engine required torque is calculated according to the actual engine torque and the actual vehicle speed; and inputting the actual vehicle speed and the target cruise vehicle speed into a preset control algorithm to obtain an engine correction demand torque, determining an engine total demand torque according to the engine static demand torque, the engine dynamic demand torque and the engine correction demand torque, and performing torque control on an engine of the vehicle according to the engine total demand torque. The engine output torque can still be accurately provided and the vehicle speed can be stably controlled under the condition that the vehicle mass is greatly changed.

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] The cruise control system or variable speed cruise control system is a driving assistance system with a high penetration rate. The system adjusts the engine output torque according to the change of driving resistance to maintain the vehicle speed at the set value. When driving on the highway for a long time, it can reduce the driving labor intensity and improve driving safety. At the same time, it can reduce unnecessary vehicle speed changes and engine torque fluctuations, and improve fuel economy.

[0003] In the prior art, a proportional integral differential (PID) algorithm calculates a vehicle speed error, an integral of the vehicle speed error, and a differential of the vehicle speed error, and then adjusts the engine torque according to the vehicle speed error, the integral of the vehicle speed error, and the differential of the vehicle speed error to achieve stable control of the vehicle speed.

[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 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] The 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 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] According to the reference vehicle characteristic parameters, the required torque when the vehicle is traveling unloaded at the target cruising speed on a flat road section is calculated as the static required torque of the engine;

[0009] Calculate the engine dynamic torque requirement according to the actual engine torque and the actual vehicle speed, where the engine dynamic torque requirement 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 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 engine correction required torque;

[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 a possible implementation, calculating the engine dynamic required torque according to the engine actual torque and the actual vehicle speed includes:

[0013] Initialize the engine dynamic demand torque, and input the engine actual torque into the torque-vehicle speed model to calculate the estimated vehicle speed, the torque-vehicle speed model is used to indicate the relationship between the estimated vehicle speed and the engine actual torque, the engine dynamic demand torque, and the 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 a possible implementation, adjusting the engine dynamic demand torque in the torque-vehicle speed model according to the vehicle speed difference includes:

[0016] Acquire an adaptive rate, the adaptive rate being used to indicate an adjustment amplitude and speed of a dynamic torque demand of an engine;

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

[0018] In one possible implementation, 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 a possible implementation, the required torque when the vehicle is traveling unloaded on a flat road section at a target cruising speed is calculated based on the reference vehicle characteristic parameters of the vehicle as the static required torque of the engine, including:

[0020] According to the reference vehicle unloaded mass, reference rolling resistance coefficient, reference air resistance coefficient, reference windward area and target cruising speed, the static driving resistance is calculated, the static driving resistance is the sum of static rolling resistance and static air resistance, the static rolling resistance is the product of the reference vehicle unloaded mass, the reference rolling resistance coefficient and gravity acceleration, 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 windward area;

[0021] The engine static demand 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 driving resistance. The engine static demand torque is the product of the static driving 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 a 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 windward 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 acquire 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 unloaded at a target cruising speed on a flat road section as a static required torque of the engine;

[0028] The processing module is further used to calculate the dynamic required torque of the engine according to the actual torque of the engine 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;

[0029] The processing module is further used 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 used to take 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's engine according to the engine total demand torque.

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

[0032] A processing module, used for initializing the engine dynamic demand torque, and inputting the engine actual torque into a torque-vehicle speed model to calculate an estimated vehicle speed, wherein the torque-vehicle speed model is used for indicating the relationship between the estimated vehicle speed and the engine actual torque, the engine 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, used for acquiring an adaptive rate, where the adaptive rate is used for indicating an adjustment amplitude and speed of a dynamic torque demand of an engine;

[0036] The processing module is used to adjust the dynamic required torque of the engine 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 driving resistance according to a reference vehicle unloaded mass, a reference rolling resistance coefficient, a reference air resistance coefficient, a reference windward area and a 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 windward area;

[0041] The processing module is used to calculate the engine static demand torque according to 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. The engine static demand torque is the product of the static driving resistance and the reference tire rolling radius and the ratio of the reference gearbox 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 windward 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 implementations 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] A cruise control method, electronic device, storage medium and program product provided in an embodiment of the present application obtain the actual engine torque, actual vehicle speed and target cruising speed of a vehicle at a current moment, and then calculate the required torque of the vehicle when it is traveling unloaded on a flat road section at the target cruising speed based on the reference vehicle characteristic parameters of the vehicle as the static required torque of the engine, calculate the dynamic required torque of the engine based on the actual engine torque and the actual vehicle speed, input the actual vehicle speed and the target cruising speed into a preset control algorithm, obtain the required torque for the vehicle to accelerate from the actual vehicle speed to the target cruising speed as the corrected required torque of the engine, and finally 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 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 decrease due to the significant change in the vehicle mass, and thus the accurate engine output torque cannot be provided, 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 reference vehicle characteristic parameters and the target cruising speed of the vehicle, and then calculates the dynamic required torque of the vehicle based on the actual engine torque, the actual vehicle speed and the reference vehicle characteristic parameters in combination with the torque-speed model. The dynamic required torque fully considers 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. Then, the torque required for the vehicle to accelerate from the actual speed to the target cruising speed is calculated as the corrected required torque of the engine. On the basis of 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 the vehicle speed can be stably controlled 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 schematic diagram of a flow chart of a cruise control method embodiment 1 provided in the present application;

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

[0056] Figure 4 A schematic diagram of a flow chart of a cruise control method embodiment 3 provided in the present application;

[0057] Figure 5 A schematic diagram of a flow chart of a fourth embodiment of a cruise control method provided by the present application;

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

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

[0060] The above drawings have shown clear embodiments of the present application, which will be described in more detail later. These drawings and text descriptions are not intended to limit the scope of the present application in any way, but to illustrate the concept of the present application to those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION

[0061] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The implementations described in the following exemplary embodiments do not represent all implementations consistent with the present application. Instead, they are merely examples of devices and methods consistent with some 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 the prior art, for heavy-duty tractors, the vehicle mass varies in a wide range. Taking a tractor as an example, the total weight of the tractor head is 9.5 tons (ton, t), and the total mass of the vehicle can reach 55t when the trailer is fully loaded. However, for the PID algorithm, the PID algorithm is based on a specific PID controller design and a specific mathematical model based on which the parameter adjustment is based. When the vehicle mass changes significantly, the PID algorithm cannot fully reflect the dynamic characteristics of the actual physical system, and therefore cannot accurately output the engine torque, which in turn leads to the inability to stably control the vehicle speed during cruise control.

[0064] Based on this, the inventive concept of the present application is to provide a cruise control method that can still accurately provide engine torque when the vehicle mass range varies greatly. Therefore, the present application calculates the static demand torque and the dynamic demand torque, and combines the engine correction 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, on the basis of the engine dynamic demand torque and the engine static demand torque, the engine correction demand torque is combined for correction, so that the engine can be provided with accurate output torque, thereby stably controlling the vehicle speed during the cruise control process.

[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, 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, and 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 technical solution of the present application and how the technical solution of the present application solves the above-mentioned technical problems are described in detail below with specific embodiments. 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 A schematic diagram of a flow chart of a cruise control method embodiment 1 provided in this application, such as Figure 1 As shown, the method comprises the following steps:

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

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

[0070] S202: Calculate the required torque of the vehicle when the vehicle is traveling unloaded at a target cruising speed 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 of the vehicle when it is traveling unloaded at a target cruising speed on a flat road section is calculated as the static required torque of the engine.

[0072] Among them, 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, so it deviates from the rolling resistance coefficient set at the factory.

[0073] In some embodiments, 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. Correspondingly, the actual vehicle characteristic parameters include: actual vehicle unloaded mass, actual rolling resistance coefficient, actual air resistance coefficient, actual frontal area, actual rotational mass conversion coefficient, actual gearbox transmission ratio, actual final reducer transmission ratio, actual transmission system mechanical efficiency and 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 the use of the vehicle, 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 engine actual torque and the actual vehicle speed.

[0076] In an embodiment of the present application, the engine dynamic demand torque is calculated based on the engine actual torque and the actual vehicle speed, wherein the engine dynamic demand torque includes: 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.

[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 engine correction required torque.

[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 as the engine correction required torque. 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 unloaded 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 engine of the vehicle 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 decrease due to the significant change in the vehicle mass, and thus the accurate engine output torque cannot be provided, which ultimately leads to the inability to stably control the vehicle speed. The present application calculates the engine torque required for the vehicle to maintain the target cruising speed when the vehicle is unloaded on a flat road according to the reference vehicle characteristic parameters of the vehicle, as the static required torque of the engine, and then calculates the dynamic required torque of the engine according to the actual engine torque and the actual vehicle speed. The dynamic torque fully considers 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 actual vehicle speed and the target cruising speed are then input into the preset control algorithm to obtain the corrected required torque of the engine. On the basis of the calculated static required torque of the engine and the dynamic required torque of the engine, the corrected required torque of the engine is added to ensure that the engine can be provided with accurate output torque under any road condition and vehicle condition, so that the vehicle speed can be stably controlled in cruise control.

[0082] Figure 3 A schematic diagram of a cruise control method embodiment 2 provided in this application, in the above Figure 2 Based on the illustrated embodiment, a specific implementation of step S203 is as follows:

[0083] S301: Initializing the engine dynamic required torque, and inputting 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-traveling resistance balance model, wherein the driving force-traveling 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] When 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 to the unloaded mass of the reference vehicle, 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 windward area, is the reference rotating mass conversion factor, It is the change value of driving resistance caused by the change of vehicle load, road slope and error of driving resistance calculation parameters.

[0090] Then replace the above formula (2) with , , , Transforming the right side of equation (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 windward area, is the reference rotating mass conversion factor, It is the change value of driving resistance caused by the change of vehicle load, road slope and error of driving resistance calculation parameters.

[0093] It should be noted that the actual engine torque is used as the value of initializing 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 engine actual 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 dynamic 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 A schematic diagram of a cruise control method embodiment 3 provided in this application, in the above Figure 3 Based on the illustrated embodiment, a specific implementation method of adjusting the engine dynamic demand torque in the torque-vehicle speed model according to the vehicle speed difference in step S302 is:

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

[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 through 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 demand torque 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, and 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, and 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 adaptation rate is obtained, and the adaptation 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 adaptation rate and the vehicle speed difference. Through the adaptation 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 A schematic diagram of a cruise control method embodiment 4 provided in this application, in the above Figures 2 to 4 Based on the illustrated embodiment, a specific implementation of step S202 is as follows:

[0105] S501: Calculate static driving resistance according to a reference vehicle unloaded 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 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] The static air resistance is the product of the 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 windward area.

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

[0114] In the embodiment of the present application, the static required torque of the engine is the product of the static driving resistance, the reference tire rolling radius, the reference gearbox transmission ratio, the reference final reducer 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 main reducer transmission ratio, the reference transmission system mechanical efficiency, the reference tire rolling radius and the static driving resistance; the static rolling resistance and the static air resistance are accurately calculated, and then the static required torque of the engine is calculated based on the static rolling resistance and the static air resistance, thereby providing 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, such as Figure 6 As shown, the cruise control device provided in this embodiment includes:

[0119] The 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; the processing module 602 is used to calculate the required torque of the vehicle when it is traveling unloaded on a flat road section at the target cruising speed according to the reference vehicle characteristic parameters of the vehicle, as the static required torque of the engine; the processing module 602 is also used to calculate the dynamic required torque of the engine according to the actual engine torque and the actual vehicle speed, and 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 the preset control algorithm to obtain the required torque of the vehicle when accelerating 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 according to 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 engine of the vehicle 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, and its implementation principle and technical effect are similar, so this embodiment will not be described in detail here.

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

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

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

[0125] The memory may include a high-speed memory (Random Access Memory, RAM), and may also include a non-volatile memory (NVM), such as at least one disk storage.

[0126] The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus, etc. The bus can be divided into an address bus, a data bus, a control bus, etc. For ease of representation, the bus in the drawings of this application is not limited to only one bus or 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 above-mentioned readable storage medium can be implemented by any type of volatile or non-volatile storage 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 memory, flash memory, magnetic disk or optical disk. The readable storage medium can be any available medium that can be accessed by a general 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 a component of the processor. The processor and the readable storage medium can be located in an application specific integrated circuit (Application Specific Integrated Circuits, referred to as: 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 only a logical function division, and there may be other divisions in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interface, device or unit, which can be electrical, mechanical or other forms.

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

[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 the function is implemented in the form of 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 part that contributes to the prior art, or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, server, or network device, etc.) to perform all or part of the steps of the methods of each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk, etc. Various media that can store program codes.

[0135] Those skilled in the art can understand that all or part of the steps of implementing the above-mentioned method embodiments can be completed by hardware related to program instructions. The aforementioned program can be stored in a computer-readable storage medium. When the program is executed, the steps of the above-mentioned method embodiments are executed; and the aforementioned storage medium includes: ROM, RAM, disk or optical disk and other media that can store program codes.

[0136] Finally, it should be noted that those skilled in the art will readily conceive of 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, which follow the general principles of the present invention and include common knowledge or customary technical means in the art not disclosed by the present invention, are not limited to the precise structure described above and shown in the drawings, and may be modified and changed in various ways without departing from the scope thereof. The scope of the present invention is limited only 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, according to the reference vehicle characteristic parameters, the required torque of the vehicle when it is traveling unloaded on a flat road section at the target cruising speed as the static required torque of the engine; Calculating the engine dynamic demand torque according to the actual engine torque and the actual vehicle speed, the engine dynamic demand torque including: 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 parameter of the vehicle and the reference vehicle characteristic parameter; Inputting the actual vehicle speed and the target cruising speed into a preset control algorithm, obtaining 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 sum of the engine static demand torque, the engine dynamic demand torque and the engine correction demand torque is taken as the engine total demand torque, so as to perform torque control on the engine of the vehicle according to the engine total demand torque.

2. The method according to claim 1, characterized in that The calculating the engine dynamic required torque according to the engine actual torque and the actual vehicle speed includes: Initializing the engine dynamic demand torque, and inputting the engine actual 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 engine actual torque, the engine dynamic demand torque, and the reference vehicle characteristic parameter; If the vehicle 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 vehicle speed difference until the vehicle 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.

3. The method according to claim 2, characterized in that The adjusting the engine dynamic demand torque in the torque-vehicle speed model according to the vehicle speed difference includes: Acquiring an adaptive rate, wherein the adaptive rate is used to indicate an adjustment amplitude and speed of the dynamic required torque of the engine; The engine dynamic demand torque is adjusted according to the adaptation rate and the vehicle speed difference.

4. 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.

5. The method according to claim 4, characterized in that The step of calculating the required torque of the vehicle when the vehicle is traveling unloaded on a flat road section at the target cruising speed according to the reference vehicle characteristic parameters of the vehicle as the static required torque of the engine includes: Calculate the static driving resistance according to the reference vehicle unloaded mass, the reference rolling resistance coefficient, the reference air resistance coefficient, the reference windward 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 windward area; The engine static required torque is calculated based on the reference gearbox transmission ratio, reference final reducer transmission 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 gearbox transmission ratio, reference final reducer transmission ratio and reference transmission system mechanical efficiency.

6. The method according to claim 2, characterized in that 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 windward 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.

7. A cruise control device, characterized in that: include: An acquisition module is used to acquire 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 the reference vehicle characteristic parameters, 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; The processing module is further used to calculate the engine dynamic demand torque according to the engine actual torque and the actual vehicle speed, wherein the engine dynamic demand 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 parameter of the vehicle and the reference vehicle characteristic parameter; The processing module is further used 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 used to determine the total engine demand torque according to the engine static demand torque, the engine dynamic demand torque and the engine corrected demand torque, so as to perform torque control on the engine of the vehicle according to the total engine demand torque.

8. 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 6.

9. 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 6 when executed by a processor.

10. 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 6 when being executed by a processor.

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