CN117601870A

CN117601870A - Method and system for calculating driver demand torque, vehicle and storage medium

Info

Publication number: CN117601870A
Application number: CN202410004389.0A
Authority: CN
Inventors: 周斌; 叶明辉; 张才干; 张猛
Original assignee: Chongqing Changan Automobile Co Ltd
Current assignee: Chongqing Changan Automobile Co Ltd
Priority date: 2024-01-02
Filing date: 2024-01-02
Publication date: 2024-02-27

Abstract

The invention relates to the technical field of automobile power system control, and discloses a method and a system for calculating the torque required by a driver, a vehicle and a storage medium, wherein the method comprises the following steps: acquiring the opening degree of an accelerator pedal, the actual vehicle speed, the actual acceleration and the gradient of a current running road of a target vehicle; determining a target acceleration based on an accelerator pedal opening and an actual vehicle speed; subtracting the actual acceleration from the target acceleration to obtain an acceleration difference; performing closed-loop correction on the required torque based on the acceleration difference to obtain corrected torque; determining a coasting resistance torque and a gradient resistance torque of the target vehicle based on the actual vehicle speed and the gradient of the current traveling road; and summing the correction torque, the sliding resistance torque and the gradient resistance torque to obtain the driver demand torque. The invention can automatically adapt to the gradient change of the road, accurately and effectively calculate the torque required by the driver and improve the driving experience of the driver.

Description

Method and system for calculating driver demand torque, vehicle and storage medium

Technical Field

The invention relates to the technical field of automobile power system control, in particular to a method and a system for calculating driver demand torque, a vehicle and a storage medium.

Background

For calculation of the driver demand torque, whether the vehicle is a traditional fuel vehicle or a traditional hybrid electric vehicle or a pure electric vehicle, the driver demand torque is calculated through an accelerator pedal opening signal and a vehicle speed signal table. However, the existing table look-up-based method for determining the torque required by the driver belongs to open loop control, cannot adapt to the gradient change of the road, and in actual driving, the driver needs to repeatedly adjust the accelerator in order to adapt to the vehicle speed change caused by the gradient change, so that the driving experience of the driver is affected.

Disclosure of Invention

In view of the above, the invention provides a method, a system, a vehicle and a storage medium for calculating a driver demand torque, which are used for solving the problem that the current table look-up mode-based determination of the driver demand torque cannot adapt to the gradient change of a road and influence the driving experience of a user.

In a first aspect, the present invention provides a method for calculating a driver demand torque, the method comprising:

acquiring the opening degree of an accelerator pedal, the actual vehicle speed, the actual acceleration and the gradient of a current running road of a target vehicle;

determining a target acceleration based on an accelerator pedal opening and an actual vehicle speed;

subtracting the actual acceleration from the target acceleration to obtain an acceleration difference;

Performing closed-loop correction on the required torque based on the acceleration difference to obtain corrected torque;

determining a coasting resistance torque and a gradient resistance torque of the target vehicle based on the actual vehicle speed and the gradient of the current traveling road;

and summing the correction torque, the sliding resistance torque and the gradient resistance torque to obtain the driver demand torque.

The method comprises the steps of obtaining the accelerator pedal opening, the actual speed and the acceleration of a target vehicle to calculate a closed-loop control quantity acceleration difference, performing closed-loop control on the required torque to obtain a correction torque, and obtaining the required torque of a driver by combining the friction resistance torque of the vehicle and the ramp resistance torque of the road running vehicles with different gradients. The invention can automatically adapt to the gradient change of the road, accurately and effectively calculate the torque required by the driver, and improve the driving experience of the driver.

In an alternative embodiment, the closed loop correction of the required torque based on the acceleration difference to obtain the corrected torque includes:

inquiring a preset first table based on the acceleration difference to obtain each parameter of PID closed-loop control, wherein the preset first table is the mapping relation between the target vehicle acceleration difference and each parameter of PID closed-loop control;

And performing PID closed-loop calculation on the required torque based on various parameters of PID closed-loop control to obtain the corrected torque.

The PID closed-loop calculation is performed on the required torque based on the acceleration difference, so that the accuracy of the required torque can be ensured, the driving stability of the vehicle is improved, the automatic adaptation driving requirements on roads with different gradients are met, the operation of a driver is simplified, and the driving experience of a user is improved.

In an alternative embodiment, determining the target acceleration based on the accelerator pedal opening and the actual vehicle speed includes:

inquiring a preset second table based on the accelerator pedal opening, and determining a vehicle speed corresponding to the accelerator pedal opening, wherein the preset second table is a mapping relation between the accelerator pedal opening of the target vehicle and the vehicle speed;

taking the minimum vehicle speed of the vehicle speed corresponding to the opening degree of the accelerator pedal and the preset maximum vehicle speed as a target vehicle speed;

subtracting the actual speed from the target speed to obtain a speed difference;

and inquiring a preset third table based on the vehicle speed difference, determining target acceleration corresponding to the vehicle speed difference, wherein the preset third table is the mapping relation between the target vehicle speed difference and the acceleration.

According to the invention, the target acceleration can be set more flexibly through the mapping relation between the opening of the accelerator pedal of the target vehicle and the vehicle speed and the mapping relation between the vehicle speed difference and the acceleration, the application requirements of different driving scenes are met, the road with different gradient changes under each driving scene can be automatically adapted, and the corresponding driver demand torque can be accurately acquired.

In an alternative embodiment, the driver demand torque calculation method further includes:

judging whether the torque required by the driver meets the preset torque requirement or not;

if the driver demand torque does not meet the preset torque demand, returning to the step of acquiring the accelerator pedal opening, the actual vehicle speed, the actual acceleration and the gradient of the current driving road of the target vehicle, and/or carrying out abnormal alarm.

The invention can more accurately obtain the driver demand torque in the process of judging the driver demand torque and the preset torque demand.

In an alternative embodiment, determining whether the driver demand torque meets the preset torque demand includes:

determining a first torque according to a maximum motor torque of a target vehicle and a maximum discharge power of a battery;

determining a second torque according to the minimum motor torque of the target vehicle and the maximum charging power of the battery, wherein the second torque is smaller than the first torque;

judging whether the driver demand torque is greater than the second torque and less than the first torque;

and if the driver demand torque is greater than the second torque and less than the first torque, determining that the driver demand torque meets the preset torque demand.

According to the method and the device, whether the required torque of the driver meets the requirement is judged through the maximum torque and the minimum torque of the target vehicle, the calculated required torque of the driver can be ensured to be within the range of the torque provided by the vehicle, and the accuracy of the required torque is greatly ensured.

In an alternative embodiment, the driver demand torque calculation method further includes, before subtracting the target acceleration from the actual acceleration:

acquiring the relative distance between the target vehicle and an obstacle in front of the target vehicle;

the target acceleration is corrected based on the relative distance.

According to the invention, the target acceleration is corrected through the vehicle distance, the actual vehicle driving scene can be closed, the torque calculation consideration is more comprehensive, and the accuracy of the calculation of the required torque of the target vehicle is improved.

In an alternative embodiment, correcting the target acceleration based on the relative distance includes:

judging whether the relative distance is smaller than a preset safety distance threshold value or not;

and if the relative distance is smaller than the preset safe distance threshold value, reducing the target acceleration based on the difference value between the preset safe distance threshold value and the relative distance.

According to the invention, the target acceleration is corrected through the judgment process of the distance between the front vehicle and the preset safety threshold, so that the functional requirement of large sliding recovery force when the distance between the front vehicle and the front vehicle is relatively close can be realized, the possible collision risk is avoided by reducing the target acceleration of the vehicle, and the running safety of the vehicle is ensured.

In a second aspect, the present invention provides a driver demand torque calculation system, the system comprising:

The acquisition module is used for acquiring the accelerator pedal opening, the actual vehicle speed, the actual acceleration and the gradient of the current running road of the target vehicle;

the first determining module is used for determining target acceleration based on the opening degree of an accelerator pedal and the actual vehicle speed;

the first calculation module is used for subtracting the actual acceleration from the target acceleration to obtain an acceleration difference;

the correction module is used for carrying out closed-loop correction on the required torque based on the acceleration difference to obtain corrected torque;

a second determination module for determining a coasting resistance torque and a gradient resistance torque of the target vehicle based on the actual vehicle speed and the gradient of the current traveling road;

and the second calculation module is used for summing the correction torque, the sliding resistance torque and the gradient resistance torque to obtain the driver demand torque.

The system for calculating the driver required torque can automatically adapt to the gradient change of the road, accurately and effectively calculate the driver required torque and improve the driving experience of the driver.

In a third aspect, the present invention provides a vehicle comprising a controller comprising: the processor is in communication connection with the memory, and the memory stores computer instructions, and the processor executes the computer instructions to perform a method for calculating the torque required by the driver according to the first aspect or any implementation manner corresponding to the first aspect.

In a fourth aspect, the present invention provides a computer-readable storage medium having stored thereon computer instructions for causing a computer to execute a method of calculating a driver demand torque of the first aspect or any of its corresponding embodiments.

The method comprises the steps of obtaining corresponding acceleration difference through the opening degree of an accelerator pedal of a target vehicle, the actual speed and the acceleration, and carrying out closed-loop correction on the required torque based on the acceleration difference to obtain corrected torque; the method has the advantages that the sliding resistance torque and the gradient resistance torque of the target vehicle are determined by combining the actual vehicle speed and the gradient of the current driving road, the driver demand torque of the target vehicle is obtained, the gradient change of the road can be automatically adapted, the calculation and consideration range of the driver demand torque obtained based on the actual driving scene is comprehensive, the accuracy is high, and the driving experience of the driver is greatly improved.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings that are needed in the description of the embodiments or the prior art will be briefly described, and it is obvious that the drawings in the description below are some embodiments of the present invention, and other drawings can be obtained according to the drawings without inventive effort for a person skilled in the art.

FIG. 1 is a flow chart diagram of a method of driver demand torque calculation according to an embodiment of the present invention;

FIG. 2 is a flow chart of another driver demand torque calculation method according to an embodiment of the present invention;

FIG. 3 is a flow chart of yet another driver demand torque calculation method according to an embodiment of the present invention;

FIG. 4 is a flow chart of a further driver demand torque calculation method according to an embodiment of the present invention;

FIG. 5 is an overall schematic of a driver demand torque calculation method according to an embodiment of the present invention;

FIG. 6 is a block diagram of a driver demand torque calculation system according to an embodiment of the present invention;

fig. 7 is a schematic structural view of a controller of a vehicle according to an embodiment of the present invention.

Detailed Description

For the purpose of making the objects, technical solutions and advantages of the embodiments of the present invention more apparent, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is apparent that the described embodiments are some embodiments of the present invention, but not all embodiments of the present invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

Currently, calculation of the torque required by the driver is often determined by a table look-up mode, and the mode belongs to open loop control and cannot adapt to complex driving scenes, such as driving scenes with gradient change of roads. Under such a scene, in order to adapt to the vehicle speed change caused by the gradient change, the driver needs to repeatedly adjust the accelerator, so that the driving experience of the driver is greatly influenced. The invention provides a method, a system, a vehicle and a storage medium for calculating the required torque of a driver, which can automatically adapt to the gradient change of a road for various driving scenes, accurately and effectively calculate the required torque of the driver, greatly improve the driving experience of the driver and meet the driving requirements of different scenes.

In an embodiment of the present invention, a driver demand torque calculation method embodiment is provided, and it should be noted that the steps illustrated in the flowchart of the drawings may be performed in a computer system such as a set of computer executable instructions, and that although a logical order is illustrated in the flowchart, in some cases, the steps illustrated or described may be performed in an order other than that illustrated herein.

In this embodiment, a method for calculating a driver required torque is provided, fig. 1 is a schematic flow chart of a method for calculating a driver required torque according to an embodiment of the present invention, and as shown in fig. 1, the flow chart includes the following steps:

Step S101, an accelerator pedal opening, an actual vehicle speed, an actual acceleration, and a gradient of a current traveling road of a target vehicle are acquired.

In the present embodiment, the accelerator pedal opening, the actual vehicle speed, the actual acceleration, and the gradient of the current running road of the target vehicle are acquired by the sensors mounted on the vehicle, and the specific acquisition manner is not particularly limited herein. For example, the opening degree of an accelerator pedal of the currently running vehicle is measured by an angle sensor; detecting the tire rotation speed of the current running vehicle through a vehicle speed sensor to obtain a corresponding vehicle speed; acquiring the acceleration of the current running vehicle through an acceleration sensor; the gradient of the current vehicle driving road is obtained through a gradient sensor or a gravity acceleration sensor, and the gradient is adaptively adjusted according to actual application scenes by way of illustration only.

Step S102, determining a target acceleration based on the accelerator pedal opening and the actual vehicle speed.

It should be noted that, for different driving modes of the vehicle, different mapping relations between the target acceleration and the vehicle speed can be set, that is, specific values of the target acceleration can be adaptively adjusted according to actual application requirements so as to meet different driving style requirements. For example, the driving mode includes: sports mode, economy mode, and standard mode. Specifically, the motion mode can increase oil consumption to improve the power of the vehicle, and has the advantages of quick acceleration and strong power; the economic mode is to reduce power to save oil consumption; the standard mode, i.e., the daily driving mode, is a state where the vehicle is in a comfortable, stable, fuel-efficient state, and is merely illustrative and not limiting.

Step S103, subtracting the actual acceleration from the target acceleration to obtain an acceleration difference.

It should be noted that, in this embodiment, the acceleration difference is used as a control amount of closed-loop control, so that the controllability of the acceleration process of the target vehicle can be ensured, so that the vehicle can be accelerated or decelerated according to the set target acceleration, and different driving experiences of the user are satisfied.

And step S104, performing closed-loop correction on the required torque based on the acceleration difference to obtain a corrected torque.

The slope change exists on the vehicle driving road under the actual vehicle driving scene, and the embodiment carries out closed-loop correction on the required torque based on the acceleration difference, so that the calculation accuracy of the required torque of the driver is greatly improved, and the driving requirements of different scenes of the driver are met.

The wheel end torque of the vehicle refers to a torque value or torque of the wheel end of the vehicle obtained by amplifying the torque of the engine or the motor of the vehicle through the vehicle transmission system, and the corrected torque in this embodiment is the torque of the wheel end of the vehicle obtained by closed loop correction.

Step S105, determining the slip resistance torque and the gradient resistance torque of the target vehicle based on the actual vehicle speed and the gradient of the current traveling road.

In this embodiment, the corresponding coasting resistance torque, also referred to as the wheel end coasting resistance torque, is determined based on the actual vehicle speed of the target vehicle, which represents the friction resistance torque to which the vehicle is subjected during running; the corresponding gradient resistance torque, also called wheel end gradient resistance torque, is determined based on the gradient of the current road on which the target vehicle is traveling, which represents the gradient resistance torque experienced by the vehicle when traveling on different gradient roads.

And S106, summing the correction torque, the sliding resistance torque and the gradient resistance torque to obtain the driver demand torque.

According to the method for calculating the driver demand torque, which is disclosed by the embodiment of the invention, for various driving scenes, the gradient change of a road can be automatically adapted, the driver demand torque can be accurately and effectively calculated, the driving experience of a driver is greatly improved, and the driving demands of different scenes are met.

In this embodiment, a method for calculating a driver required torque is provided, and fig. 2 is a schematic flow chart of another method for calculating a driver required torque according to an embodiment of the present invention, as shown in fig. 2, the flow chart includes the following steps:

step S201, an accelerator pedal opening, an actual vehicle speed, an actual acceleration, and a gradient of a current traveling road of the target vehicle are acquired. Please refer to step S101 in the embodiment shown in fig. 1 in detail, which is not described herein.

Step S202, a target acceleration is determined based on the accelerator pedal opening and the actual vehicle speed.

Specifically, the step S202 includes:

step S2021, based on the accelerator pedal opening, queries a preset second table, which is a mapping relationship between the target vehicle accelerator pedal opening and the vehicle speed, to determine the vehicle speed corresponding to the accelerator pedal opening.

The preset second table in this embodiment is a target vehicle speed MAP, which refers to a data table used in the interpolation method, that is, a data MAP table of the accelerator opening and the corresponding target vehicle speed, as shown in table 1. In addition, the accelerator pedal of a hybrid vehicle or a fuel vehicle is also referred to as an accelerator pedal.

TABLE 1

X: throttle opening	0	20	40	60	80	100
							Y: target vehicle speed	0	40	80	120	160	180

As is clear from table 1, the corresponding Y target vehicle speed of 40km/h can be obtained by inquiring the X accelerator opening 20. It should be noted that, the specific value of MAP is set manually based on the empirical value during the vehicle development stage, and the data meeting the requirements can be modified adaptively by the calibration engineer during the vehicle debugging stage based on the vehicle performance requirements.

In step S2022, the minimum vehicle speed of the vehicle speed corresponding to the accelerator opening degree and the preset maximum vehicle speed is set as the target vehicle speed.

The preset maximum vehicle speed is a fixed value of a maximum vehicle speed limit value set by the vehicle, and specific values thereof are not limited herein, and are determined based on a gear of the vehicle in actual demand, a driving mode, a fault state, and a maximum vehicle speed allowed to run by the vehicle determined by user setting. For example, for a manual-gear automobile, the first gear is a gear for normal starting or climbing a steep slope, and the suitable speed is about 10km/h, and the highest speed can be set to 15km/h, which is only used as an illustration and not as a limitation. The target vehicle speed is determined through the operation of taking down the preset maximum vehicle speed, so that the vehicle speed limiting function can be realized, and the damage to parts caused by the fact that the vehicle exceeds the allowable maximum vehicle speed is avoided.

In step S2023, the target vehicle speed is subtracted from the actual vehicle speed to obtain a vehicle speed difference.

In a specific embodiment, a preset target vehicle speed MAP is queried according to the opening of the accelerator pedal, a target vehicle speed original value corresponding to the opening of the accelerator pedal is determined, and then the target vehicle speed is obtained by taking the target vehicle speed original value down with a set maximum vehicle speed limit value.

In step S2024, a preset third table is queried based on the vehicle speed difference, the target acceleration corresponding to the vehicle speed difference is determined, and the preset third table is a mapping relationship between the target vehicle speed difference and the acceleration.

The preset third table in this embodiment is a data mapping table of target acceleration MAP, that is, a vehicle speed difference and a corresponding target acceleration, and the target acceleration can be set more flexibly by using a mapping relationship between the opening of the accelerator pedal of the target vehicle and the vehicle speed and a mapping relationship between the vehicle speed difference and the acceleration, so that the application requirements of different driving scenes are satisfied, roads with different gradient changes in each driving scene can be automatically adapted, and corresponding driver demand torque can be accurately obtained.

In step S203, the target acceleration is subtracted from the actual acceleration to obtain an acceleration difference. Please refer to step S103 in the embodiment shown in fig. 1 in detail, which is not described herein.

And step S204, performing closed-loop correction on the required torque based on the acceleration difference to obtain a corrected torque.

Specifically, the step S204 includes:

step S2041, inquiring a preset first table based on the acceleration difference to obtain each parameter of the PID closed-loop control, wherein the preset first table is the mapping relation between the target vehicle acceleration difference and each parameter of the PID closed-loop control.

Note that PID (Proportional Integral Derivative) is a closed-loop control of the ratio, integral, and derivative of an error generated by comparing information acquired from real-time data of a controlled object with a given value, and is also called a ratio-integral-derivative control, which has control parameters of the ratio P, the integral I, and the derivative D. The preset first table in this embodiment is a data mapping table of PID parameters MAP, that is, the acceleration difference and the P-term parameter, I-term parameter, and D-term parameter corresponding thereto.

It should be noted that, specific values of the three parameters P, I and D may be set as fixed values, however, when the specific values are set as fixed values, the control effect is poor in the whole vehicle speed range; in the embodiment, values of the P, I parameter and the D parameter are set to be variable parameters by adopting an interpolation method, the variable parameters change along with the change of the acceleration difference, and the MAP table of each parameter of the PID is checked through the acceleration difference to determine.

And step S2042, performing PID closed-loop calculation on the required torque based on various parameters of PID closed-loop control to obtain corrected torque.

In this embodiment, PID closed-loop control is performed according to the acceleration difference, so as to obtain a corresponding wheel end correction torque, which is also referred to as wheel end PID correction torque. Specifically, PID closed loop calculation is carried out on the required torque based on the acceleration difference, so that the accuracy of the required torque can be ensured, the driving stability of the vehicle is improved, the automatic adaptation driving requirements on roads with different gradients are met, the operation of a driver is simplified, and the driving experience of a user is improved.

In step S205, the slip resistance torque and the gradient resistance torque of the target vehicle are determined based on the actual vehicle speed and the gradient of the current traveling road. Please refer to step S105 in the embodiment shown in fig. 1 in detail, which is not described herein.

Step S206, summing the correction torque, the sliding resistance torque and the gradient resistance torque to obtain the driver demand torque. Please refer to step S106 in the embodiment shown in fig. 1 in detail, which is not described herein.

In this embodiment, a method for calculating a driver required torque is provided, and fig. 3 is a schematic flow chart of another method for calculating a driver required torque according to an embodiment of the present invention, as shown in fig. 3, the flow chart includes the following steps:

Step S301 acquires an accelerator pedal opening, an actual vehicle speed, an actual acceleration, and a gradient of a current traveling road of a target vehicle. Please refer to step S101 in the embodiment shown in fig. 1 in detail, which is not described herein.

Step S302, a target acceleration is determined based on the accelerator pedal opening and the actual vehicle speed. Please refer to step S202 in the embodiment shown in fig. 2, which is not described herein.

In the case of a vehicle equipped with the adaptive cruise control (Adaptive Cruise Control, ACC) function, the target acceleration is corrected by the feedback signal of the vehicle distance sensor, and the functions of small coasting recovery force (increasing the target acceleration) when the vehicle is farther from the front vehicle and large coasting recovery force (decreasing the target acceleration) when the vehicle is closer to the front vehicle are realized. Therefore, in the present embodiment, correction of the target acceleration is added, and torque calculation is performed using the corrected target acceleration. Specifically, the target acceleration is corrected, the actual vehicle driving scene can be closed, the torque calculation consideration is more comprehensive, and the accuracy of the calculation of the required torque of the target vehicle is improved.

Step S303, a relative distance between the target vehicle and an obstacle in front of the target vehicle is acquired.

In this embodiment, the relative distance between the host vehicle and the obstacle in front of the host vehicle is acquired by the radar mounted on the host vehicle.

Step S304, correcting the target acceleration based on the relative distance.

Specifically, the step S304 includes:

step S3041, determining whether the relative distance is smaller than a preset safety distance threshold.

In this embodiment, the preset safe distance threshold is not specifically limited herein, and is set according to the actual driving requirement. For example, the preset safe distance threshold is 10m, which is only illustrative.

Step S3042, if the relative distance is smaller than the preset safe distance threshold, reducing the target acceleration based on the difference between the preset safe distance threshold and the relative distance.

In this embodiment, if the relative distance is smaller than the preset safety distance threshold, that is, the following distance between the host vehicle and the vehicle in front of the host vehicle is too short, the required slip recovery force is large (that is, the required deceleration is large), and the target acceleration of the host vehicle is reduced to perform the vehicle distance correction. If the relative distance is not smaller than the preset safe distance threshold, that is, the following distance between the host vehicle and the vehicle in front of the host vehicle is long (that is, the vehicle distance is large), the required slip recovery force is small (that is, the required deceleration is small) when the vehicle slips and recovers, and the target acceleration of the host vehicle is increased to correct the vehicle distance. Specifically, the target acceleration is corrected through the judgment process of the distance between the front vehicle and the preset safety threshold, so that the functional requirement of large sliding recovery force when the distance between the front vehicle and the front vehicle is relatively close can be met, the possible collision risk is avoided by reducing the target acceleration of the vehicle, and the running safety of the vehicle is ensured.

In step S305, the target acceleration is subtracted from the actual acceleration to obtain an acceleration difference. Please refer to step S103 in the embodiment shown in fig. 1 in detail, which is not described herein.

And step S306, performing closed-loop correction on the required torque based on the acceleration difference to obtain a corrected torque. Please refer to step S204 in the embodiment shown in fig. 2 in detail, which is not described herein.

Step S307 determines the coasting resistance torque and the gradient resistance torque of the target vehicle based on the actual vehicle speed and the gradient of the current traveling road. Please refer to step S105 in the embodiment shown in fig. 1 in detail, which is not described herein.

Step S308, the correction torque, the sliding resistance torque and the gradient resistance torque are summed to obtain the driver demand torque. Please refer to step S106 in the embodiment shown in fig. 1 in detail, which is not described herein.

In practical applications, the value of the torque at the wheel end of the vehicle meets a certain range requirement, namely, the maximum torque at the wheel end and the minimum torque at the wheel end exist, so that the determination of the torque required by the driver is increased to ensure that the obtained value of the torque required by the driver is within the range of the torque provided by the vehicle.

In an electric vehicle or a hybrid vehicle, a motor is used as a power source, and generated torque is transmitted to wheels through a transmission device such as a gearbox to form wheel end torque so as to drive the vehicle. Therefore, the torque of the motor directly influences the torque of the wheel end of the vehicle; in addition, the torque of the wheel end of the wheel also affects the working state of the motor, namely, when the wheel encounters large resistance, the wheel end can generate certain resistance, thereby affecting the output power and the efficiency of the motor. From the motor torque calculation formula, i.e., motor torque (T) =9550×power (P)/rotation speed (n), it is known that power is related to the battery of the vehicle. Specifically, the battery is used as a power reserve of an electric vehicle or a hybrid electric vehicle, can drive a motor to run, and provides power for the electric vehicle. The range of torque that the vehicle can provide in this embodiment is related to the vehicle's battery and motor.

Step S309, determining whether the driver demand torque meets the preset torque demand.

Specifically, the step S309 includes:

step S3091, determining a first torque according to a motor maximum torque of the target vehicle and a maximum discharge power of the battery.

The maximum torque at the wheel end of the target vehicle is related to the maximum torque that can be supported by the motor and the maximum electric energy that can be provided by the battery, that is, the maximum discharge power that can be provided by the battery in the driving state. In the present embodiment, therefore, the maximum torque of the wheel end currently corresponding to the vehicle, that is, the first torque is determined according to the maximum torque of the motor of the target vehicle and the maximum discharge power of the battery.

Step S3092, determining a second torque according to the motor minimum torque and the battery maximum charging power of the target vehicle, the second torque being smaller than the first torque.

The minimum torque at the wheel end of the target vehicle is related to the minimum torque that can be supported by the motor and the minimum electric energy that can be provided by the battery, that is, the maximum charging power recovered by the battery in the energy state. In this embodiment, therefore, the wheel end minimum torque, i.e., the second torque, currently corresponding to the vehicle is determined according to the motor minimum torque and the battery maximum charging power of the target vehicle.

In step S3093, it is determined whether the driver demand torque is greater than the second torque and less than the first torque.

In this embodiment, the wheel end driver demand torque is limited between the wheel end minimum torque and the wheel end maximum torque to ensure rationality and high accuracy thereof.

In step S3094, if the driver demand torque is greater than the second torque and less than the first torque, it is determined that the driver demand torque meets the preset torque demand.

In this embodiment, the wheel end driver demand torque is obtained by taking the wheel end maximum torque to be smaller and then taking the wheel end minimum torque to be larger.

Step S3010, if the driver demand torque does not meet the preset torque demand, the step of obtaining the accelerator opening, the actual vehicle speed, the actual acceleration and the gradient of the current driving road of the target vehicle is returned again, and/or an abnormality alarm is performed.

In this embodiment, when the torque required by the driver at the wheel end reaches the limit of the maximum torque or the minimum torque at the wheel end, the PID closed loop correction is not performed, so that the problem of driving impact caused by excessive correction is avoided, the phenomenon of overcharging or overdischarging of the battery is avoided to a certain extent, and the damage to the battery of the vehicle is reduced.

According to the embodiment of the invention, whether the driver demand torque meets the requirement is judged through the maximum torque and the minimum torque of the target vehicle, so that the calculated driver demand torque can be ensured to be within the torque range provided by the vehicle, the precision of the demand torque is greatly ensured, and the damage to the vehicle battery is reduced.

In one embodiment, referring to fig. 4 and 5, the flow of the driver demand torque calculation method includes:

step S1, inquiring a preset target vehicle speed MAP according to the opening degree of an accelerator pedal, determining a target vehicle speed original value corresponding to the opening degree of the accelerator pedal, and comparing the target vehicle speed original value with a maximum vehicle speed limit value V _max Taking out the vehicle to obtain a target vehicle speed V _{Target object} The method comprises the steps of carrying out a first treatment on the surface of the Based on formula V _diff ＝V _{Target object} -V _{Actual practice is that of} Target vehicle speed V _{Target object} And the actual vehicle speed V _{Actual practice is that of} Subtracting to obtain a vehicle speed difference V _diff 。

Step S2, according to the vehicle speed difference V _diff Inquiring a preset target acceleration MAP, and determining a target acceleration A _{Target object} The method comprises the steps of carrying out a first treatment on the surface of the Based on formula A _diff ＝A _{Target object} -A _{Actual practice is that of} Will target acceleration A _{Target object} And actual acceleration A _{Actual practice is that of} Subtracting to obtain an acceleration difference A _diff . The step also comprises the step of aiming at the target acceleration A according to the distance between the vehicles in front _{Target object} And (5) performing correction.

In the step S3 of the method,according to the actual vehicle speed V _{Actual practice is that of} Inquiring a preset sliding resistance curve MAP, and determining wheel end sliding resistance torque T corresponding to the vehicle speed _{Resistance force} The method comprises the steps of carrying out a first treatment on the surface of the Inquiring a preset gradient resistance curve MAP according to a gradient signal, and determining a wheel end gradient resistance torque T corresponding to the gradient _{Gradient of slope} 。

Step S4, through the acceleration difference A _diff Inquiring a preset P item parameter MAP, an I item parameter MAP and a D item parameter MAP to obtain the P item parameter, the I item parameter and the D item parameter; according to the acceleration difference A _diff PID closed loop calculation is carried out to obtain wheel end PID correction torque T _PID 。

Step S5: torque T of wheel end sliding resistance _{Resistance force} Wheel end gradient resistance torque T _{Gradient of slope} And wheel end PID corrected torque T _PID Adding the three to obtain a wheel end driver required torque original value, and then based on the currently available wheel end maximum torque T of the vehicle _max And wheel end minimum torque T _min Performing up-down limitation to obtain the required torque T of the wheel end driver _{Demand for} 。

In summary, the closed-loop control-based driver demand torque calculation method of the present invention can automatically adjust the torque output to adapt to the change of the road gradient, thereby maintaining the target vehicle speed demanded by the driver; the invention not only can simplify the operation of the driver and enhance the driving experience; the functions of creeping, normal driving, sliding recovery, vehicle speed limiting and the like of the vehicle can be realized, the traditional two-dimensional MAP is simplified into one-dimensional MAP, the workload and the calibration difficulty in the vehicle development process are reduced, and the development period is effectively shortened.

In this embodiment, a system for calculating the torque required by the driver is further provided, and the system is used to implement the foregoing embodiments and preferred embodiments, and will not be described again. The term "module" as used below may be a combination of software and/or hardware that implements a predetermined function. While the system described in the following embodiments is preferably implemented in software, implementation in hardware, or a combination of software and hardware, is also possible and contemplated.

The present invention provides a driver demand torque calculation system, as shown in fig. 6, comprising:

an acquisition module 601 is configured to acquire an accelerator pedal opening, an actual vehicle speed, an actual acceleration, and a gradient of a current traveling road of a target vehicle.

The first determining module 602 is configured to determine a target acceleration based on an accelerator opening and an actual vehicle speed.

The first calculating module 603 is configured to subtract the target acceleration from the actual acceleration to obtain an acceleration difference.

The correction module 604 is configured to perform closed-loop correction on the required torque based on the acceleration difference, so as to obtain a corrected torque.

The second determination module 605 is configured to determine a slip resistance torque and a gradient resistance torque of the target vehicle based on the actual vehicle speed and the gradient of the current traveling road.

The second calculation module 606 is configured to sum the correction torque, the coast drag torque, and the grade drag torque to obtain a driver demand torque.

In some alternative embodiments, the first determining module 602 includes: the first, second, third and fourth determination sub-modules; the first determining submodule is used for inquiring a preset second table based on the accelerator pedal opening, determining the vehicle speed corresponding to the accelerator pedal opening, and the preset second table is the mapping relation between the accelerator pedal opening of the target vehicle and the vehicle speed; the second determining submodule is used for taking the minimum vehicle speed of the vehicle speed corresponding to the opening degree of the accelerator pedal and the preset maximum vehicle speed as a target vehicle speed; the third determining submodule is used for subtracting the actual speed from the target speed to obtain a speed difference; and the fourth determining submodule is used for inquiring a preset third table based on the vehicle speed difference, determining target acceleration corresponding to the vehicle speed difference and setting the preset third table as a mapping relation between the target vehicle speed difference and the acceleration.

In some alternative embodiments, the correction module 604 includes: a first correction sub-module and a second correction sub-module; the first correction submodule is used for inquiring a preset first table based on the acceleration difference to obtain various parameters of PID closed-loop control, wherein the preset first table is a mapping relation between the acceleration difference of the target vehicle and the various parameters of the PID closed-loop control; and the second correction sub-module is used for performing PID closed-loop calculation on the required torque based on various parameters of PID closed-loop control to obtain the correction torque.

In some alternative embodiments, the system further comprises: judging a sub-module and a termination sub-module; the judging submodule is used for judging whether the torque required by the driver meets the preset torque requirement or not; and the termination sub-module is used for returning to the step of acquiring the accelerator pedal opening, the actual vehicle speed, the actual acceleration and the gradient of the current driving road of the target vehicle and/or carrying out abnormal alarm if the torque required by the driver does not meet the preset torque requirement.

In some alternative embodiments, the judging submodule includes: the first judging unit, the second judging unit, the third judging unit and the fourth judging unit; the first judging unit is used for determining a first torque according to the maximum motor torque of the target vehicle and the maximum discharge power of the battery; a second judgment unit for determining a second torque according to a motor minimum torque of the target vehicle and a maximum charging power of the battery, the second torque being smaller than the first torque; a third judging unit for judging whether the driver demand torque is greater than the second torque and less than the first torque; and the fourth judging unit is used for determining that the driver demand torque meets the preset torque demand if the driver demand torque is larger than the second torque and smaller than the first torque.

In some alternative embodiments, the system further comprises: a collection sub-module and an adjustment sub-module; the collecting sub-module is used for acquiring the relative distance between the target vehicle and the obstacle in front of the target vehicle; and the adjustment sub-module is used for correcting the target acceleration based on the relative distance.

In some alternative embodiments, the adjusting sub-module includes: a first adjusting unit and a second adjusting unit; the first adjusting unit is used for judging whether the relative distance is smaller than a preset safety distance threshold value or not; and the second adjusting unit is used for reducing the target acceleration based on the difference value between the preset safe distance threshold value and the relative distance if the relative distance is smaller than the preset safe distance threshold value.

Further functional descriptions of the above respective modules are the same as those of the above corresponding embodiments, and are not repeated here.

The driver demand torque computing system in this embodiment is presented in the form of functional units, referred to herein as ASIC (Application Specific Integrated Circuit ) circuits, processors and memory executing one or more software or firmware programs, and/or other devices that can provide the functionality described above.

According to the driver demand torque calculation system provided by the embodiment of the invention, the closed-loop control quantity acceleration difference is calculated by acquiring the accelerator pedal opening, the actual vehicle speed and the acceleration of the target vehicle, the demand torque is subjected to closed-loop control, the correction torque is combined with the friction resistance moment of the vehicle and the ramp resistance moment of the road running vehicle with different gradients, and the driver demand torque is obtained. The invention can automatically adapt to the gradient change of the road, accurately and effectively calculate the torque required by the driver, and improve the driving experience of the driver.

The embodiment of the invention also provides a vehicle, which comprises a controller. The controller in this embodiment is a vehicle domain controller, and is configured to perform operations such as power supply/power outage, sleep wakeup, etc. on the sub-controller and the network node that are suspended under the controller, and meanwhile, each power supply interface can collect and output real-time current. Other controllers having the above functions are applicable.

Fig. 7 is a schematic structural diagram of the controller according to an alternative embodiment of the present invention, as shown in fig. 7, where the controller includes: one or more processors 10, memory 20, and interfaces for connecting the various components, including high-speed interfaces and low-speed interfaces. The various components are communicatively coupled to each other using different buses and may be mounted on a common motherboard or in other manners as desired. The processor may process instructions executing within the controller, including instructions stored in or on memory to display graphical information of the GUI on an external input/output device, such as a display apparatus coupled to the interface. In some alternative embodiments, multiple processors and/or multiple buses may be used, if desired, along with multiple memories and multiple memories. Also, multiple controllers may be connected, each providing part of the necessary operations (e.g., as a server array, a set of blade servers, or a multiprocessor system). One processor 10 is illustrated in fig. 7.

The processor 10 may be a central processor, a network processor, or a combination thereof. The processor 10 may further include a hardware chip, among others. The hardware chip may be an application specific integrated circuit, a programmable logic device, or a combination thereof. The programmable logic device may be a complex programmable logic device, a field programmable gate array, a general-purpose array logic, or any combination thereof.

Wherein the memory 20 stores instructions executable by the at least one processor 10 to cause the at least one processor 10 to perform a method for implementing the embodiments described above.

The memory 20 may include a storage program area that may store an operating system, at least one application program required for functions, and a storage data area; the storage data area may store data created according to the use of the controller, etc. In addition, the memory 20 may include high-speed random access memory, and may also include non-transitory memory, such as at least one magnetic disk storage device, flash memory device, or other non-transitory solid-state storage device. In some alternative embodiments, memory 20 may optionally include memory located remotely from processor 10, which may be connected to the controller via a network. Examples of such networks include, but are not limited to, the internet, intranets, local area networks, mobile communication networks, and combinations thereof.

Memory 20 may include volatile memory, such as random access memory; the memory may also include non-volatile memory, such as flash memory, hard disk, or solid state disk; the memory 20 may also comprise a combination of the above types of memories.

The controller also includes a communication interface 30 for the master control chip to communicate with other devices or communication networks.

The embodiments of the present invention also provide a computer readable storage medium, and the method according to the embodiments of the present invention described above may be implemented in hardware, firmware, or as a computer code which may be recorded on a storage medium, or as original stored in a remote storage medium or a non-transitory machine readable storage medium downloaded through a network and to be stored in a local storage medium, so that the method described herein may be stored on such software process on a storage medium using a general purpose computer, a special purpose processor, or programmable or special purpose hardware. The storage medium can be a magnetic disk, an optical disk, a read-only memory, a random access memory, a flash memory, a hard disk, a solid state disk or the like; further, the storage medium may also comprise a combination of memories of the kind described above. It will be appreciated that a computer, processor, microprocessor master chip or programmable hardware includes a storage component that can store or receive software or computer code that, when accessed and executed by the computer, processor or hardware, implements the methods illustrated by the embodiments described above.

Although embodiments of the present invention have been described in connection with the accompanying drawings, various modifications and variations may be made by those skilled in the art without departing from the spirit and scope of the invention, and such modifications and variations fall within the scope of the invention as defined by the appended claims.

Claims

1. A method of calculating a driver demand torque, the method comprising:

determining a target acceleration based on the accelerator pedal opening and the actual vehicle speed;

determining a coasting resistance torque and a gradient resistance torque of a target vehicle based on the actual vehicle speed and a gradient of the current traveling road;

2. The driver demand torque calculation method according to claim 1, characterized in that the closed-loop correction of the demand torque based on the acceleration difference, to obtain a corrected torque, includes:

Inquiring a preset first table based on the acceleration difference to obtain each parameter of PID closed-loop control, wherein the preset first table is a mapping relation between the acceleration difference of the target vehicle and each parameter of PID closed-loop control;

and performing PID closed-loop calculation on the required torque based on each parameter of the PID closed-loop control to obtain the corrected torque.

3. The driver demand torque calculation method according to claim 1, characterized in that the determining a target acceleration based on the accelerator pedal opening and the actual vehicle speed includes:

subtracting the actual vehicle speed from the target vehicle speed to obtain a vehicle speed difference;

and inquiring a preset third table based on the vehicle speed difference, and determining target acceleration corresponding to the vehicle speed difference, wherein the preset third table is a mapping relation between the target vehicle speed difference and the acceleration.

4. A driver demand torque calculation method according to any one of claims 1 to 3, characterized in that the method further comprises:

judging whether the driver demand torque meets a preset torque demand;

and if the driver demand torque does not meet the preset torque demand, returning to the step of acquiring the accelerator pedal opening, the actual vehicle speed, the actual acceleration and the gradient of the current driving road of the target vehicle, and/or carrying out abnormal alarm.

5. The driver demand torque calculation method according to claim 4, characterized in that the determining whether the driver demand torque satisfies a preset torque demand includes:

and if the driver demand torque is greater than the second torque and less than the first torque, determining that the driver demand torque meets a preset torque demand.

6. The driver demand torque calculation method according to claim 1, characterized in that before subtracting the actual acceleration from the target acceleration, the method further comprises:

and correcting the target acceleration based on the relative distance.

7. The driver demand torque calculation method according to claim 6, characterized in that the correcting the target acceleration based on the relative distance includes:

and if the relative distance is smaller than a preset safe distance threshold value, reducing the target acceleration based on a difference value between the preset safe distance threshold value and the relative distance.

8. A driver demand torque computing system, the system comprising:

a first determining module configured to determine a target acceleration based on the accelerator opening and the actual vehicle speed;

a second determination module for determining a coasting resistance torque and a gradient resistance torque of a target vehicle based on the actual vehicle speed and a gradient of the current traveling road;

9. A vehicle, the vehicle comprising a controller, the controller comprising: a memory and a processor in communication with each other, the memory having stored therein computer instructions, the processor executing the computer instructions to perform the driver demand torque calculation method of any one of claims 1 to 7.

10. A computer-readable storage medium having stored thereon computer instructions for causing a computer to execute the driver demand torque calculation method according to any one of claims 1 to 7.