Torque Control Method, Device, Terminal Device and Storage Medium

Abstract

The present application discloses a torque control method, device, terminal device, and storage medium. The torque control method includes: starting a control program for the retarder braking torque; identifying the retarder gear to determine the retarder braking torque curve corresponding to the retarder gear, where the retarder braking torque curve includes a plurality of braking torque values and the target vehicle speeds corresponding to the braking torque values; obtaining the current actual vehicle speed and calculating the deviation between the target vehicle speed and the actual vehicle speed; and controlling the retarder braking torque according to the braking torque value based on the deviation. The present application solves the problem of low efficiency of electric braking for recovering electric energy.

Description

Technical Field

[0001] This application relates to the technical field of vehicles, and particularly to a torque control method, apparatus, terminal device, and storage medium. Background Art

[0002] New energy vehicles can recover the electric energy lost during braking and coasting, thereby effectively reducing the power consumption rate and increasing the driving range of the vehicle. The basic principle of regenerative braking of new energy vehicles is: when the vehicle is coasting or braking, its drive motor acts as a generator, converting the kinetic energy of the vehicle into electric energy for charging the power battery, which has a very obvious effect on improving energy consumption.

[0003] However, when a new energy vehicle brakes downhill, if the retarder is not turned on, the brake pedal needs to be pressed to activate the electric brake. But when pressing the brake, the traditional brake is also activated at the same time, resulting in a decrease in the proportion of electric brake recovery. Summary of the Invention

[0004] The main purpose of this application is to provide a torque control method, apparatus, terminal device, and storage medium, aiming to solve the problem of low efficiency of electric brake energy recovery.

[0005] To achieve the above object, this application provides a torque control method, which includes:

[0006] Start the control program of the retarder braking torque;

[0007] Identify the retarder gear to determine the retarder braking torque curve corresponding to the retarder gear. The retarder braking torque curve includes a number of braking torque values and the target vehicle speeds corresponding to the braking torque values;

[0008] Obtain the current actual vehicle speed and calculate the deviation between the target vehicle speed and the actual vehicle speed;

[0009] Based on the deviation, control the retarder braking torque according to the braking torque value.

[0010] Optionally, the braking torque value includes a slip balance torque. The step of controlling the retarder braking torque according to the braking torque value based on the deviation includes:

[0011] Judge whether the deviation exceeds a preset value;

[0012] If the deviation exceeds the value, control the retarder braking torque based on the slip balance torque;

[0013] If the deviation does not exceed the value, control the retarder braking torque through a preset torque stabilization algorithm.

[0014] Optionally, the step of controlling the retardation braking torque based on the rolling-slope balance torque includes:

[0015] Comparing the retardation braking torque with the rolling-slope balance torque to obtain a torque difference;

[0016] Adjusting the retardation braking torque according to the torque difference and the rolling-slope balance torque.

[0017] Optionally, the step of controlling the retardation braking torque by a preset torque stabilization algorithm includes:

[0018] Obtaining a torque range based on the vehicle speed error between the target vehicle speed and the actual vehicle speed;

[0019] Controlling the retardation braking torque according to the torque range.

[0020] Optionally, after the step of starting the control program of the retardation braking torque, it further includes:

[0021] Judging whether a preset electric braking circuit channel is safe;

[0022] If the electric braking circuit channel is safe, execute the step of identifying the retardation gear to determine the retardation braking torque curve corresponding to the retardation gear and subsequent steps;

[0023] If the electric braking circuit channel is not safe, turn off the retardation braking torque and give a warning prompt.

[0024] Optionally, after the step of controlling the retardation braking torque according to the braking torque value based on the deviation, it further includes:

[0025] Return to execute the step of judging whether a preset electric braking circuit channel is safe.

[0026] Optionally, before the step of starting the preset retardation braking torque, it further includes:

[0027] Receiving a preset status signal to obtain corresponding status information;

[0028] Judging whether to execute the step of starting the preset control program and subsequent steps according to the status information.

[0029] An embodiment of the present application further provides a torque control device, and the torque control device includes:

[0030] A starting module, configured to start a control program of a retardation braking torque;

[0031] An identification module, configured to identify the retarder gear position to determine a retarder braking torque curve corresponding to the retarder gear position, where the retarder braking torque curve includes a plurality of braking torque values and target vehicle speeds corresponding to the braking torque values;

[0032] A calculation module, configured to obtain the current actual vehicle speed and calculate a deviation between the target vehicle speed and the actual vehicle speed;

[0033] A control module, configured to control the retarder braking torque based on the deviation according to the braking torque value.

[0034] An embodiment of the present application further provides a terminal device, where the terminal device includes a memory, a processor, and a torque control program stored on the memory and executable on the processor. When the torque control program is executed by the processor, the steps of the torque control method described above are implemented.

[0035] An embodiment of the present application further provides a computer-readable storage medium, where a torque control program is stored on the computer-readable storage medium. When the torque control program is executed by a processor, the steps of the torque control method described above are implemented.

[0036] The torque control method, device, terminal device, and storage medium provided by the embodiments of the present application start a control program for the retarder braking torque; identify the retarder gear position to determine a retarder braking torque curve corresponding to the retarder gear position, where the retarder braking torque curve includes a plurality of braking torque values and target vehicle speeds corresponding to the braking torque values; obtain the current actual vehicle speed and calculate a deviation between the target vehicle speed and the actual vehicle speed; control the retarder braking torque based on the deviation according to the braking torque value. By identifying the retarder gear position to determine the corresponding retarder braking torque curve, the retarder braking torque is controlled, so that the actual vehicle speed is maintained within a certain range, and the kinetic energy and potential energy can be recovered to the maximum extent, solving the problem of low efficiency of electric braking for recovering electric energy. Based on the solution of the present application, starting from the problem of energy recovery in the real world, a method for controlling the electric braking torque based on the target vehicle speed is proposed, and the effectiveness of the torque control method proposed by the present application is verified on this method. Finally, through the control of the torque by the method of the present application, the efficiency of recovering electric energy is significantly improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 It is a schematic diagram of functional modules of a terminal device to which the torque control device of the present application belongs;

[0038] Figure 2 It is a schematic flowchart of a first exemplary embodiment of the torque control method of the present application;

[0039] Figure 3 It is a schematic diagram of the power architecture of the torque control method of the present application;

[0040] Figure 4 This is the flowchart of the downhill cruise torque control method for the torque control method of this application;

[0041] Figure 5 This is the schematic flowchart of the second exemplary embodiment of the torque control method of this application;

[0042] Figure 6 This is the schematic diagram of the correlation method between the traditional braking torque and the brake pedal involved in the torque control method of this application;

[0043] Figure 7 This is the schematic diagram of the abc segmented setting method of the retarder torque and the target vehicle speed setting for the torque control method of this application;

[0044] Figure 8 This is the schematic flowchart of the third exemplary embodiment of the torque control method of this application;

[0045] Figure 9 This is the schematic flowchart of the fourth exemplary embodiment of the torque control method of this application;

[0046] Figure 10 This is the schematic diagram of the vehicle speed closed-loop control algorithm involved in the torque control method of this application;

[0047] Figure 11 This is the schematic flowchart of the fifth exemplary embodiment of the torque control method of this application;

[0048] Figure 12 This is the schematic flowchart of the sixth exemplary embodiment of the torque control method of this application;

[0049] Figure 13 This is the schematic flowchart of the seventh exemplary embodiment of the torque control method of this application;

[0050] Figure 14 This is the decision flowchart of the powertrain output torque control mode for the torque control method of this application.

[0051] The realization, functional features and advantages of the purpose of this application will be further described with reference to the embodiments and the accompanying drawings. Detailed Embodiments

[0052] It should be understood that the specific embodiments described herein are only used to explain this application and are not used to limit this application.

[0053] The main solution of the embodiment of the present application is as follows: start the control program of the retarder braking torque; identify the retarder gear to determine the retarder braking torque curve corresponding to the retarder gear, where the retarder braking torque curve includes a number of braking torque values and the target vehicle speeds corresponding to the braking torque values; obtain the current actual vehicle speed, and calculate the deviation between the target vehicle speed and the actual vehicle speed; based on the deviation, control the retarder braking torque according to the braking torque value. By identifying the retarder gear to determine the corresponding retarder braking torque curve, the retarder braking torque is controlled, so that the actual vehicle speed is maintained within a certain range, and the kinetic energy and potential energy can be recovered to the maximum extent, solving the problem of low efficiency of electric braking for recovering electric energy. Based on the solution of the present application, starting from the problem of energy recovery in the real world, a method for controlling the electric braking torque based on the target vehicle speed is proposed, and the effectiveness of the torque control method proposed in the present application is verified on this method. Finally, through the control of the torque by the method of the present application, the efficiency of recovering electric energy is significantly improved.

[0054] The embodiment of the present application considers that for new energy vehicles during downhill braking, if the retarder is not turned on, the brake pedal needs to be stepped on to activate the electric braking. However, when stepping on the brake, the traditional brake is also activated at the same time, resulting in a decrease in the proportion of electric braking recovery.

[0055] Therefore, the solution of the embodiment of the present application starts from the problem of energy recovery in the real world, proposes a method for controlling the electric braking torque based on the target vehicle speed, verifies the effectiveness of the torque control method proposed in the present application on this method, and finally, through the control of the torque by the method of the present application, the efficiency of recovering electric energy is significantly improved.

[0056] Specifically, refer to Figure 1 , Figure 1 which is a schematic diagram of the functional modules of the terminal device to which the torque control device of the present application belongs. The torque control device can be a device independent of the terminal device and capable of performing torque control and deviation calculation, and it can be carried on the terminal device in the form of hardware or software. The terminal device can be an intelligent mobile terminal with data processing functions such as a mobile phone or a tablet computer, or a fixed terminal device or a server with data processing functions, etc.

[0057] In this embodiment, the terminal device to which the torque control device belongs at least includes an output module 110, a processor 120, a memory 130, and a communication module 140.

[0058] The operating system and the torque control program are stored in the memory 130. The torque control device can store information such as the control program for the starting retardation braking torque; the identified retardation gear, the retardation braking torque curve corresponding to the determined retardation gear, the retardation braking torque curve including a number of braking torque values and the target vehicle speeds corresponding to the braking torque values; the currently obtained actual vehicle speed, the deviation calculated between the target vehicle speed and the actual vehicle speed; the control of the retardation braking torque based on the deviation according to the braking torque value, etc. in the memory 130; the output module 110 can be a display screen, etc. The communication module 140 can include a WIFI module, a mobile communication module, a Bluetooth module, etc., and communicates with external devices or servers through the communication module 140.

[0059] Among them, when the torque control program in the memory 130 is executed by the processor, the following steps are implemented:

[0060] Start the control program for the retardation braking torque;

[0061] Identify the retardation gear to determine the retardation braking torque curve corresponding to the retardation gear, the retardation braking torque curve including a number of braking torque values and the target vehicle speeds corresponding to the braking torque values;

[0062] Obtain the current actual vehicle speed and calculate the deviation between the target vehicle speed and the actual vehicle speed;

[0063] Based on the deviation, control the retardation braking torque according to the braking torque value.

[0064] Furthermore, when the torque control program in the memory 130 is executed by the processor, the following steps are also implemented:

[0065] Judge whether the deviation exceeds a preset value;

[0066] If the deviation exceeds the value, control the retardation braking torque based on the slope balance torque;

[0067] If the deviation does not exceed the value, control the retardation braking torque through a preset torque stabilization algorithm.

[0068] Furthermore, when the torque control program in the memory 130 is executed by the processor, the following steps are also implemented:

[0069] Compare the retardation braking torque with the slope balance torque to obtain a torque difference;

[0070] Adjust the retardation braking torque according to the torque difference and the slope balance torque.

[0071] Further, when the torque control program in the memory 130 is executed by the processor, the following steps are also implemented:

[0072] Based on the vehicle speed error between the target vehicle speed and the actual vehicle speed, obtain a torque range;

[0073] According to the torque range, control the retard braking torque.

[0074] Further, when the torque control program in the memory 130 is executed by the processor, the following steps are also implemented:

[0075] Judge whether the preset electric braking circuit channel is safe;

[0076] If the electric braking circuit channel is safe, execute the step of identifying the retard gear to determine the retard braking torque curve corresponding to the retard gear and the subsequent steps;

[0077] If the electric braking circuit channel is not safe, turn off the retard braking torque and give a warning prompt.

[0078] Further, when the torque control program in the memory 130 is executed by the processor, the following steps are also implemented:

[0079] Return to execute the step of judging whether the preset electric braking circuit channel is safe.

[0080] Further, when the torque control program in the memory 130 is executed by the processor, the following steps are also implemented:

[0081] By receiving a preset status signal, obtain the corresponding status information;

[0082] According to the status information, judge whether to execute the step of starting the preset control program and the subsequent steps.

[0083] In this embodiment, through the above solution, specifically, the control program for the retarder braking torque is started; the retarder gear is identified to determine the retarder braking torque curve corresponding to the retarder gear. The retarder braking torque curve includes a number of braking torque values and the target vehicle speeds corresponding to the braking torque values; the current actual vehicle speed is obtained, and the deviation between the target vehicle speed and the actual vehicle speed is calculated; based on the deviation, the retarder braking torque is controlled according to the braking torque value. By identifying the retarder gear to determine the corresponding retarder braking torque curve, the retarder braking torque is controlled, so that the actual vehicle speed is maintained within a certain range, and the kinetic energy and potential energy can be recovered to the maximum extent, solving the problem of low efficiency of electric braking for recovering electric energy. Based on the solution of this application, starting from the problem of energy recovery in the real world, a method for controlling the electric braking torque based on the target vehicle speed is proposed, and the effectiveness of the torque control method proposed in this application is verified on this method. Finally, through the control of the torque by the method of this application, the efficiency of recovering electric energy is significantly improved.

[0084] Based on the above terminal device architecture but not limited to the above architecture, the method embodiment of this application is proposed.

[0085] Refer to Figure 2 , Figure 2 is a schematic flowchart of the first exemplary embodiment of the torque control method of this application. The torque control method includes:

[0086] Step S210, start the control program for the retarder braking torque;

[0087] Specifically, in a new energy vehicle, the powertrain control system receives the status signal and starts the control program for the retarder braking torque according to the signal. In this way, the new energy vehicle can recover the electric energy lost during braking and coasting, thereby reducing the electric energy consumption rate and increasing the driving range of the vehicle. For example, the driver starts the control program for the retarder torque by operating the retarder handle, accelerator pedal, brake pedal, and gear handle of a pure electric mining truck.

[0088] Step S220, identify the retarder gear to determine the retarder braking torque curve corresponding to the retarder gear. The retarder braking torque curve includes a number of braking torque values and the target vehicle speeds corresponding to the braking torque values;

[0089] Specifically, different retarder gears correspond to different retarder strengths and retarder target vehicle speeds. The retarder strength is determined by the braking torque output by the power system, and different retarder gears correspond to different retarder braking torque curves. In addition, different retarder gears can be set according to the actual situation. For example, if multiple retarder gears are required for a project, multiple retarder torque curves corresponding to the retarder gears can be designed.

[0090] Step S230: Obtain the current actual vehicle speed and calculate the deviation between the target vehicle speed and the actual vehicle speed.

[0091] Specifically, judge the deviation between the actual vehicle speed and the retarder target vehicle speed, and control the retarder braking torque according to the deviation. Through the deviation between the actual vehicle speed and the retarder target vehicle speed, it can be calculated whether the actual vehicle speed and the retarder target vehicle speed differ too much. Then, according to the deviation and the braking torque value, adjust the retarder braking torque to keep the actual vehicle speed of the vehicle within the specified range, so as to maximize the recovery of kinetic energy and potential energy.

[0092] Step S240: Based on the deviation, control the retarder braking torque according to the braking torque value.

[0093] Specifically, the purpose of setting the downhill retarder torque control is to minimize the driver's intervention of stepping on the brake during the downhill braking process of the vehicle, and completely rely on the electric braking force of the power system to stabilize the vehicle speed within the speed range expected by the driver. In this way, when the vehicle is going downhill, the driver can not step on the brake, and the vehicle can rely on the electric braking torque to drag the vehicle to generate electricity, so that the vehicle maintains the speed set by the driver, and the potential energy during downhill is maximally converted into electric energy recovery, extending the vehicle's cruising range.

[0094] In addition, since the braking energy during downhill is converted into heat energy through the auxiliary braking of the retarder and not converted into electric energy, therefore, in the embodiment of the present application, as Figure 3 shown Figure 3Schematic diagram of the power architecture for the torque control method of this application. As shown in the figure, there are power battery (0), brake pedal (1), accelerator pedal (2), retarder handle (3), powertrain control system (4), electric drive system 1 (5), electric drive system 2 (6), drive chain 1 (7), drive chain 2 (8), power coupler (9), drive shaft (10), rear axle assembly (11), right wheel (12), left wheel (13), vehicle information display system (14), and gear shift lever (15). Among them, the powertrain control system is connected to the retarder handle. The powertrain control system (4) is responsible for identifying the driver's control commands. These operating instruction devices include accelerator pedal (1), brake pedal (2), retarder handle (3), gear shift lever (15), etc. Among them, the accelerator pedal (1) is used to control the magnitude of the total output drive torque of the power system. The brake pedal (2) controls both the braking force of the traditional brake system and the magnitude of the electric braking torque. The retarder handle (3) is mainly used to control the stable vehicle speed under the electric braking state when going downhill. According to the project design requirements, the retarder handle (3) can be designed into 3 levels, 4 levels, 5 levels, etc. The gear shift lever (15) is used to control the forward and backward movement of the vehicle, shifting to N gear for standby, etc. Through the powertrain control system (11), the retarder signal of the retarder handle can be received, the retarder gear can be identified, and the retarder gear and the corresponding retarder braking torque curve can be directly determined. There is no need to use the retarder for auxiliary braking, and the braking energy during downhill can be converted into electric energy. Among them, after entering the downhill retarder torque control, the target vehicle speed during retarder driving is adjusted by the retarder handle. The retarder handle has multiple gears. The higher the gear, the lower the retarder vehicle speed. At the same vehicle speed, the corresponding electric braking torque is also greater, and the tendency to slide downhill on the same slope is also weaker, and the finally stable vehicle speed is also lower.

[0095] Through the above solution in this embodiment, specifically, by starting the control program of the retarder braking torque; identifying the retarder gear to determine the retarder braking torque curve corresponding to the retarder gear. The retarder braking torque curve includes several braking torque values and the target vehicle speeds corresponding to the braking torque values; obtaining the current actual vehicle speed, and calculating the deviation between the target vehicle speed and the actual vehicle speed; based on the deviation, controlling the retarder braking torque according to the braking torque value. By identifying the retarder gear to determine the corresponding retarder braking torque curve, thereby controlling the retarder braking torque, so that the actual vehicle speed is maintained within a certain range, the kinetic energy and potential energy can be recovered to the maximum extent, and the problem of low efficiency of electric braking for recovering electric energy can be solved. Based on the solution of this application, starting from the problem of energy recovery in the real world, a method for controlling electric braking torque based on the target vehicle speed is proposed, and the effectiveness of the torque control method proposed in this application is verified on this method. Finally, through the control of torque by the method of this application, the efficiency of recovering electric energy is significantly improved.

[0096] Refer to Figure 4 ,Figure 4 This is the flowchart of the downhill cruise torque control method for this application. As shown in the figure, execute S31: Start the downhill cruise torque control and begin to start the downhill cruise torque control program.

[0097] First, execute S32: Electric braking circuit diagnosis. After entering this control process, first, the safety diagnosis of the electric braking circuit channel needs to be carried out. If the power system is not suitable for electric braking charging at this time, charging is not allowed, and proceed to S33; if charging is allowed at this time, proceed to the next step S34.

[0098] Then, execute S33: Turn off the retarder braking torque and give a warning. If electric braking is not allowed, a warning message is sent on the vehicle information display system to remind the driver that the electric braking cannot be turned on and to step on the brake in time to decelerate.

[0099] Then, execute S34: Retarder gear identification. If electric braking is allowed, at this time, first, the position of the retarder handle needs to be identified, and the retarder level is set to gear 0, or gear 1, or gear 2, etc.

[0100] Then, execute S35: Set the retarder force and target speed. Different retarder gears correspond to different retarder forces and retarder target speeds. Among them, the retarder force is determined by the braking torque output by the power system.

[0101] Then, execute S36: Vehicle speed compliance judgment. This step of the program mainly judges the deviation between the actual vehicle speed and the retarder target speed. After the deviation is less than a certain value, proceed to S38. If the deviation is greater than a certain value, proceed to S37.

[0102] Then, execute S37: Retarder torque control. Based on the retarder torque control curve selected in S35, control the electric braking torque according to the current vehicle speed.

[0103] Then, execute S38: Target vehicle speed control. When the vehicle speed reaches near the retarder target speed, it is necessary to keep the vehicle speed as stable as possible and also keep the torque stable. If the torque fluctuates or the vehicle speed fluctuates, it will affect the driver's experience.

[0104] Finally, after executing S37 or S38, the software will return to S32 to loop again.

[0105] In this way, when the vehicle is going downhill, the driver can not step on the brake, and the vehicle relies on the electric braking torque to drag the vehicle to generate electricity, so that the vehicle maintains the speed set by the driver, maximizing the conversion of the potential energy of going downhill into electric energy recovery and extending the vehicle's cruising range.

[0106] Refer to Figure 5 , Figure 5 This is the schematic flowchart of the second exemplary embodiment of the torque control method for this application. Based on the above Figure 2In the illustrated embodiment, the braking torque value includes a slope-slide balance torque. Step S240 controls the retarder braking torque based on the deviation according to the braking torque value, and includes:

[0107] Step S510, determine whether the deviation exceeds a preset value;

[0108] Specifically, determine the deviation between the actual vehicle speed and the retarder target vehicle speed. If the deviation is less than or equal to the preset value, that is, the actual vehicle speed is not much different from the target vehicle speed, then execute step S530. If the deviation does not exceed the value, control the retarder braking torque through a preset torque stabilization algorithm. If the deviation is greater than this value, that is, the actual vehicle speed is quite different from the target vehicle speed, then execute step S520. If the deviation exceeds the value, control the retarder braking torque based on the slope-slide balance torque.

[0109] Step S520, if the deviation exceeds the value, control the retarder braking torque based on the slope-slide balance torque;

[0110] Specifically, if the deviation exceeds the value, control the retarder braking torque based on the slope-slide balance torque, and the braking torque value includes the slope-slide balance torque. As Figure 6 shown, Figure 6 is a schematic diagram of the correlation method between the traditional braking torque and the brake pedal involved in the torque control method of the present application. Among them, the traditional dynamic electric braking recovery is divided into coasting braking and braking. To ensure the handling comfort of the vehicle, the braking torque of coasting braking is usually not set very large, such as Figure 6 the 0% curve of the brake pedal shown in. When the driver steps on the brake pedal, the braking torque of the system will select different braking torque curves according to the depth of the pedal.

[0111] As Figure 7 shown, Figure 7 is a schematic diagram of the abc segmented setting method of the retarder torque and the target vehicle speed setting of the torque control method of the present application. Figure 7Specifically shown are three electric braking torque setting curves for the 0th gear, the 1st gear, and the 2nd gear, and a slope-holding balance torque is also shown. Among them, the retardation intensity is determined by the braking torque output by the power system. Different retardation gears correspond to different retardation intensities and retardation target vehicle speeds, and different retardation gears correspond to different retardation braking torque curves. The retardation target vehicle speed 0 set for the 0th gear is the highest, and the electric braking torque is the smallest at the same vehicle speed. The retardation target vehicle speed II set for the 2nd gear is the lowest, and the electric braking torque is the largest at the same vehicle speed. The slope-holding balance torque is used as a reference standard. By comparing with the slope-holding balance torque and adjusting the retardation braking torque, the actual vehicle speed of the vehicle can be controlled. In addition, different retardation gears can be set according to the actual situation. For example, if multiple retardation gears are required for a project, multiple retardation torque curves corresponding to the retardation gears can be designed.

[0112] Step S530, if the deviation does not exceed the value, control the retardation braking torque through a preset torque stabilization algorithm.

[0113] Specifically, since both torque fluctuations and vehicle speed fluctuations will affect the driver's experience. Therefore, when the actual vehicle speed reaches near the retardation target vehicle speed, it is necessary to keep the actual vehicle speed as stable as possible and also keep the torque stable. Therefore, the torque stabilization algorithm is used to maintain the stability of the retardation braking torque. By restricting the retardation braking torque within a certain output range, the stability of the target vehicle speed is improved, including, but not limited to, algorithms for closed-loop vehicle speed control.

[0114] In this embodiment, through the above solution, specifically, it is determined whether the deviation exceeds a preset value; if the deviation exceeds the value, the retardation braking torque is controlled based on the slope-holding balance torque; if the deviation does not exceed the value, the retardation braking torque is controlled through a preset torque stabilization algorithm. By calculating the deviation between the actual vehicle speed and the target vehicle speed, it is judged whether the gap between the actual vehicle speed and the target vehicle speed is too large, and different solutions are set according to the size of the deviation, which can improve the accuracy of the retardation braking torque control and the torque control precision.

[0115] Refer to Figure 8 , Figure 8 is a schematic flowchart of the third exemplary embodiment of the torque control method of the present application. Based on the above Figure 5 shown embodiment, step S520, controlling the retardation braking torque based on the slope-holding balance torque includes:

[0116] Step S810, compare the retardation braking torque with the slope-holding balance torque to obtain a torque difference;

[0117] Specifically, the retard braking torque is compared with the rollback balance torque to obtain a comparison result. The rollback balance torque is used as a reference standard. By comparing with the rollback balance torque and adjusting the retard braking torque, the actual vehicle speed can be controlled.

[0118] As Figure 7 shown, Figure 7 is a schematic diagram of the segmented setting method of the retard torque abc and the target vehicle speed setting for the torque control method of the present application. Among them, different retard gears correspond to different retard forces and retard target vehicle speeds. The retard force is determined by the braking torque output by the power system. The selection of the retard braking torque curve is as Figure 7 shown. Different retard gears correspond to different retard braking torque curves. Among them, Figure 7 shows three electric braking torque setting curves for gear 0, gear I, and gear II. The retard target vehicle speed set for gear 0 is the highest, and the electric braking torque is also the smallest at the same vehicle speed. The retard target vehicle speed set for gear II is the lowest, and the electric braking torque is also the largest at the same vehicle speed. If the project uses more retard gears, more retard torque curves also need to be designed.

[0119] Step S820: Adjust the retard braking torque according to the torque difference and the rollback balance torque.

[0120] Specifically, if the current retard braking torque output by the power system is greater than the rollback balance torque, the vehicle will decelerate; if the current retard braking torque output by the power system is less than the rollback balance torque, the vehicle will accelerate. For example, when the actual vehicle speed reaches the set vehicle speed II, the electric braking torque is equal to the rollback balance torque, and the vehicle acceleration is 0, and it starts to travel at a constant speed. If the vehicle ramp changes or the driving resistance changes, it will cause a change in the vehicle speed. Suppose the vehicle speed continues to increase, the electric braking torque will continue to increase according to the c trend, and finally it will reach equilibrium with the rollback balance torque, and the vehicle speed will finally stabilize near the vehicle speed II.

[0121] In this embodiment, through the above solution, specifically by comparing the retard braking torque with the rollback balance torque, a torque difference is obtained; according to the torque difference and the rollback balance torque, the retard braking torque is adjusted. By comparing the output retard braking torque with the set rollback balance torque and adjusting the retard braking torque, the kinetic energy and potential energy of the vehicle can be recovered to the maximum extent, and the efficiency of recovering electric energy during the vehicle's driving process can be improved.

[0122] Referring to Figure 9 , Figure 9 is a schematic flowchart of the fourth exemplary embodiment of the torque control method of the present application. Based on the above Figure 5 shown embodiment, step S530: Control the retard braking torque through a preset torque stabilization algorithm.

[0123] Step S910: Obtain a torque range based on the vehicle speed error between the target vehicle speed and the actual vehicle speed.

[0124] Specifically, since both torque fluctuations and vehicle speed fluctuations can affect the driver's experience. Therefore, when the actual vehicle speed approaches the retard target vehicle speed, it is necessary to keep the actual vehicle speed as stable as possible and also keep the torque stable. Thus, a torque stability algorithm is used to maintain the stability of the retard braking torque. By constraining the retard braking torque within a certain output range, the stability of the target vehicle speed is improved. Among them, it includes, but is not limited to, algorithms for vehicle speed closed-loop control. In this embodiment, vehicle speed closed-loop control is preferred, as Figure 10 shown Figure 10 is a schematic diagram of the vehicle speed closed-loop control algorithm involved in the torque control method of this application. By calculating the target vehicle speed and the actual vehicle speed, the vehicle speed error is obtained. The vehicle speed error is calculated with the P-term coefficient to obtain the P-term result, the vehicle speed error is input into the I-term coefficient value selector and the integrator to obtain the I-term result, the vehicle speed error is input into the difference solver and the D-term to obtain the D-term result, and then the P-term result, the I-term result, and the D-term result are calculated simultaneously to obtain the output torque range of the retard braking torque.

[0125] Step S920: Control the retard braking torque according to the torque range.

[0126] Specifically, by outputting a retard braking torque command according to the torque range and controlling the retard braking torque within the torque range, the retard braking torque and the actual vehicle speed can be kept within a certain range, improving the stability of the retard braking torque.

[0127] In this embodiment, through the above solution, specifically, by obtaining a torque range based on the vehicle speed error between the target vehicle speed and the actual vehicle speed; controlling the retard braking torque according to the torque range. By calculating the torque range of the retard braking torque, the stability of the output retard braking torque can be improved.

[0128] Refer to Figure 11 , Figure 11 is a schematic flowchart of the fifth exemplary embodiment of the torque control method of this application. Based on the above Figure 2 shown embodiment, after step S210 of starting the control program of the retard braking torque, it further includes:

[0129] Step S1110: Determine whether the preset electric braking circuit channel is safe;

[0130] Specifically, after entering this control process, the safety diagnosis of the electro-braking circuit channel is first carried out. If the power system is not suitable for electro-braking charging at this time, charging is not allowed, and it enters S33; if charging is allowed at this time, it enters the next step S34. There are many factors for not allowing charging. For example: as shown in Figure 3 For the power battery (0) shown in, if the power of the power battery exceeds the safety value, or the battery voltage exceeds the safety value, or the battery temperature exceeds the safety value, etc., the battery is not allowed to continue charging.

[0131] Step S1120, if the electro-braking circuit channel is safe, execute the control program for starting the retarder braking torque; identify the retarder gear to determine the retarder braking torque curve corresponding to the retarder gear. The retarder braking torque curve includes several braking torque values and the target vehicle speeds corresponding to the braking torque values; obtain the current actual vehicle speed, and calculate the deviation between the target vehicle speed and the actual vehicle speed; based on the deviation, control the retarder braking torque according to the braking torque value.

[0132] Specifically, if the electro-braking circuit channel is safe, execute the steps of identifying the retarder gear to determine the retarder braking torque curve corresponding to the retarder gear. The retarder braking torque curve includes the braking torque value and the target vehicle speed corresponding to the braking torque value; obtain the current actual vehicle speed, calculate the deviation between the target vehicle speed and the actual vehicle speed; based on the deviation, control the retarder braking torque according to the braking torque value. Adding the safety detection of the electro-braking circuit channel improves the safety of torque control.

[0133] Step S1130, if the electro-braking circuit channel is not safe, turn off the retarder braking torque and give a warning.

[0134] Specifically, if electro-braking is not allowed, a warning message is sent on the on-vehicle information display system (14) as shown in Figure 3 to remind the driver that the electro-braking cannot be turned on, so that the driver can step on the brake to decelerate in time. In this way, the phenomena of false alarms and missed alarms are minimized.

[0135] Through the above solutions in this embodiment, specifically, it is determined whether the preset electro-braking circuit channel is safe; if the electro-braking circuit channel is safe, execute the steps of determining the corresponding retarder braking torque curve according to the identified retarder gear and the subsequent steps; if the electro-braking circuit channel is not safe, turn off the retarder braking torque and give a warning. Adding the safety detection of the electro-braking circuit channel improves the safety of torque control and minimizes the phenomena of false alarms and missed alarms.

[0136] Refer to Figure 12 , Figure 12 is the flow chart of the sixth exemplary embodiment of the torque control method of this application. Based on the above Figure 11In the illustrated embodiment, after step S240 of controlling the retarder braking torque according to the braking torque value based on the deviation, the method further includes:

[0137] Step S1210 of returning to execute the step of determining whether the preset electric braking circuit channel is safe.

[0138] Specifically, in this embodiment, through the above solution, specifically, it is determined whether the preset electric braking circuit channel is safe; if the electric braking circuit channel is not safe, the retarder braking torque is turned off and a warning is prompted; if the electric braking circuit channel is safe, the retarder gear is identified to determine the retarder braking torque curve corresponding to the retarder gear, where the retarder braking torque curve includes a plurality of braking torque values and the target vehicle speeds corresponding to the braking torque values; the current actual vehicle speed is obtained, and the deviation between the target vehicle speed and the actual vehicle speed is calculated; based on the deviation, the retarder braking torque is controlled according to the braking torque value; and the step of returning to execute the step of determining whether the preset electric braking circuit channel is safe is performed. By cyclically detecting the safety of the electric braking circuit channel and cyclically obtaining the actual vehicle speed for calculation, the buffer braking torque can be controlled in real time to ensure the accuracy and safety of torque control.

[0139] Refer to Figure 13 , Figure 13 is a schematic flowchart of the seventh exemplary embodiment of the torque control method of the present application. Based on the above Figure 2 illustrated embodiment, before step S210 of starting the control program for the retarder braking torque, the method further includes:

[0140] Step S1310 of obtaining corresponding status information by receiving a preset status signal;

[0141] Specifically, before starting the control program for the downhill retarder electric braking torque, the power-train control system receives a status signal to obtain corresponding status information. It should be noted that the status signal is set according to the actual situation, and the embodiments of the present application do not limit this. More specifically, taking Figure 3 as an example, the power-train control system (4) receives the status information sent by the drive signal transmitted by the accelerator pedal (1), the braking signal transmitted by the brake pedal (2), the retarder signal transmitted by the retarder handle (3), and the gear signal of the gear handle (15) to decide whether to enter the downhill retarder electric braking mode.

[0142] Step S1320 of determining whether to execute the preset control program and subsequent steps according to the status information.

[0143] Specifically, the specific conditions are set according to the project requirements. For example: if the handle is not in the N gear position, and the driver does not step on the accelerator pedal or the brake pedal, and the retarder handle is turned on or the vehicle recognizes a coasting situation, then the control program for the downhill retarder electric braking torque is started.

[0144] In this embodiment, through the above solution, specifically, by receiving a preset status signal to obtain corresponding status information; according to the status information, it is determined whether to execute the preset control program and subsequent steps. Receive a preset status signal to obtain corresponding status information; according to the status information, it is determined whether to execute the preset control program and subsequent steps. By starting the control program for the retarder braking torque; identifying the retarder gear to determine the retarder braking torque curve corresponding to the retarder gear, the retarder braking torque curve includes a plurality of braking torque values and the target vehicle speeds corresponding to the braking torque values; obtaining the current actual vehicle speed, and calculating the deviation between the target vehicle speed and the actual vehicle speed; based on the deviation, controlling the retarder braking torque according to the braking torque value. By receiving the status signal to obtain the status information and deciding whether to start the control program for the buffer braking torque, an optimal solution can be obtained, improving the efficiency of torque control.

[0145] Reference Figure 14 , Figure 14 is the decision flow chart for the power-train output torque control mode of the torque control method of this application. Based on the above Figure 3 shown, the specific steps of the mode management process are as follows:

[0146] S0: Start the output torque control. When the vehicle successfully powers on, the control software will enter S0.

[0147] S1: Idle mode judgment. The software decides whether to enter S10 based on the status information of the accelerator pedal (1), brake pedal (2), retarder handle (3), gear handle (15), etc. The specific conditions are set according to the project requirements. For example: if the handle is in the N gear position, then enter S10. If the handle is not in N, then enter S2.

[0148] S10: Idle torque control. When the handle is in N, to ensure the safety of the vehicle, both drive chain 1 (7) and drive chain 2 (8) are disconnected, and at this time the vehicle cannot transmit power. In principle, the electric drive system 1 (5) and the electric drive system 2 (6) no longer respond to the driver's throttle control.

[0149] S2: Driving mode judgment. The software decides whether to enter S20 based on the status information of the accelerator pedal (1), brake pedal (2), retarder handle (3), gear lever (15), etc. The specific conditions are set according to project requirements. For example, if the lever is in the D gear position and the driver steps on the accelerator pedal without stepping on the brake pedal, then enter S20. If the lever is not in D or the driver does not step on the brake pedal, then enter S3.

[0150] S20: Driving torque control. In this mode, the software decides the total torque of the powertrain based on the current driving speed of the vehicle and the travel of the accelerator pedal, and then decides the optimal gear and the optimal distribution ratio of the two drive chains based on the vehicle speed and the total output torque.

[0151] S3: Downhill retarder electric braking judgment. The software decides whether to enter S30 based on the status information of the accelerator pedal (1), brake pedal (2), retarder handle (3), gear lever (15), etc. The specific conditions are set according to project requirements. For example, if the lever is not in the N gear position, and the driver does not step on the accelerator pedal (1) nor the brake pedal (2), and the retarder handle (3) is turned on or the vehicle recognizes a coasting downhill situation, then enter S30. Otherwise, enter S4.

[0152] S30: Downhill retarder torque control. The purpose of setting the downhill retarder torque control is to minimize the driver's intervention by stepping on the brake during the vehicle's downhill braking process, and to rely entirely on the electric braking force of the power system to stabilize the vehicle speed within the range expected by the driver. Here, kinetic energy and potential energy can be recovered to the maximum extent, and the cruising range can be extended. After entering the downhill retarder torque control, the target speed of the slow driving is adjusted by the retarder handle (3). The retarder handle has multiple gears. The higher the gear, the lower the slow driving speed. At the same vehicle speed, the corresponding electric braking torque is also greater, and the tendency of coasting downhill on the same slope is also weaker, and the finally stabilized vehicle speed is also lower. The detailed control process in this mode is shown in Figure 5 。

[0153] S4: Coasting electric braking judgment. The software decides whether to enter S30 based on the status information of the accelerator pedal (1), brake pedal (2), retarder handle (3), gear lever (15), etc. The specific conditions are set according to project requirements. For example, if the lever is not in the N gear position, and the driver does not step on the accelerator pedal nor the brake pedal, and the retarder handle is turned off or the vehicle recognizes a flat road coasting situation, then enter S40. Otherwise, enter S5.

[0154] S40: Coasting electric braking torque control. In this mode, the coasting electric braking torque usually sets a relatively small electric braking torque according to the current vehicle speed. When coasting on a flat road and making the vehicle have a certain deceleration to slow down, kinetic energy can also be recovered. Among them, the specific value of the electric braking torque is calibrated and determined according to customer requirements and vehicle working conditions.

[0155] S5: Brake electric braking judgment. Based on the status information of the accelerator pedal (1), brake pedal (2), retarder handle (3), gear lever (15), etc., the software decides whether to enter S50. The specific conditions are set according to project requirements. For example: If the lever is not in the N gear position, and the driver steps on the brake pedal, and the retarder handle is closed or the vehicle recognizes that the vehicle does not process the retarder braking state, then enter S50. Otherwise, enter S0.

[0156] S50: Brake electric braking torque control. In this mode, the electric braking torque is usually determined according to the current vehicle speed and the travel of the brake pedal (2). A calibrated two-dimensional array can be designed to calibrate the magnitude of the braking torque according to different vehicle speeds and the depth of the brake pedal (2) based on the actual working conditions and the driver's feeling requirements.

[0157] In this way, through Figure 3 The powertrain control system (4) in it is responsible for identifying the driver's control instructions. These operating instruction devices include the accelerator pedal (1), brake pedal (2), retarder handle (3), gear lever (15), etc. Among them, the accelerator pedal (1) is used to control the magnitude of the total output drive torque of the power system. The brake pedal (2) controls both the braking force of the traditional braking system and the electric braking torque. The retarder handle (3) is mainly used to control the stable vehicle speed in the electric braking state when going downhill. According to the project design requirements, the retarder handle (3) can be designed into 3 levels, 4 levels, 5 levels, etc. The gear lever (15) is used to control the forward, reverse, and N gear standby of the vehicle. After the powertrain control system (4) identifies the driver's operation instructions, it makes a power distribution decision instruction based on various data of the power system, and sends and displays the relevant data information or warning information to the in-vehicle information display system (14), so that the driver can conveniently view the control results.

[0158] In addition, the embodiment of the present application also proposes a torque control device, and the torque control device includes:

[0159] A start module, used to start the control program of the retarder braking torque;

[0160] An identification module, used to identify the retarder gear to determine the retarder braking torque curve corresponding to the retarder gear. The retarder braking torque curve includes a number of braking torque values and the target vehicle speeds corresponding to the braking torque values;

[0161] A calculation module, used to obtain the current actual vehicle speed and calculate the deviation between the target vehicle speed and the actual vehicle speed;

[0162] A control module, used to control the retarder braking torque based on the deviation according to the braking torque value.

[0163] For the principle and implementation process of torque control in this embodiment, please refer to the above-mentioned embodiments, and details will not be repeated here.

[0164] In addition, an embodiment of the present application further provides a terminal device, which includes a memory, a processor, and a torque control program stored on the memory and executable on the processor. When the torque control program is executed by the processor, it implements the steps of the torque control method as described above.

[0165] Since all the technical solutions of the foregoing embodiments are adopted when the torque control program is executed by the processor, it at least has all the beneficial effects brought by all the technical solutions of the foregoing embodiments, and details will not be repeated here.

[0166] In addition, an embodiment of the present application further provides a computer-readable storage medium, on which a torque control program is stored. When the torque control program is executed by the processor, it implements the steps of the torque control method as described above.

[0167] Since all the technical solutions of the foregoing embodiments are adopted when the torque control program is executed by the processor, it at least has all the beneficial effects brought by all the technical solutions of the foregoing embodiments, and details will not be repeated here.

[0168] Compared with the prior art, the torque control method, device, terminal device, and storage medium proposed in the embodiments of the present application start a control program for the retarder braking torque; identify the retarder gear to determine the retarder braking torque curve corresponding to the retarder gear, and the retarder braking torque curve includes a plurality of braking torque values and the target vehicle speeds corresponding to the braking torque values; obtain the current actual vehicle speed, and calculate the deviation between the target vehicle speed and the actual vehicle speed; based on the deviation, control the retarder braking torque according to the braking torque value. By identifying the retarder gear to determine the corresponding retarder braking torque curve, the retarder braking torque is controlled, so that the actual vehicle speed is maintained within a certain range, and the kinetic energy and potential energy can be recovered to the maximum extent, solving the problem of low efficiency of electric braking for recovering electric energy. Based on the solution of the present application, starting from the problem of energy recovery in the real world, a method for controlling the electric braking torque based on the target vehicle speed is proposed, and the effectiveness of the torque control method proposed in the present application is verified on this method. Finally, through the control of the torque by the method of the present application, the efficiency of recovering electric energy is significantly improved.

[0169] It should be noted that in this document, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, such that a process, method, article or system comprising a series of elements not only includes those elements but also includes other elements not expressly listed, or elements inherent to such process, method, article or system. Without further limitation, an element defined by the statement "comprising a..." does not exclude the presence of additional identical elements in the process, method, article or system comprising such element.

[0170] The serial numbers of the embodiments of the present application above are for description only and do not represent the superiority or inferiority of the embodiments.

[0171] Through the description of the above embodiments, those skilled in the art can clearly understand that the above embodiment methods can be implemented by means of software plus a necessary general hardware platform. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation. Based on such understanding, the technical solution of the present application, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. The computer software product is stored in a storage medium as described above (such as ROM / RAM, magnetic disk, optical disc) and includes several instructions to enable a terminal device (which may be a mobile phone, computer, server, controlled terminal, or network device, etc.) to execute the methods of each embodiment of the present application.

[0172] The above are only the preferred embodiments of the present application, and do not limit the patent scope of the present application accordingly. Any equivalent structure or equivalent process transformation made by using the specification and drawings of the present application, or directly or indirectly applied in other related technical fields, shall equally be included in the patent protection scope of the present application.

Claims

1. A torque control method, characterized in that, The torque control method includes the following steps: Start the control program for the retarder braking torque; Identify the retarder gear to determine the retarder braking torque curve corresponding to the retarder gear. The retarder braking torque curve includes a number of braking torque values and the target vehicle speeds corresponding to the braking torque values; Obtain the current actual vehicle speed and calculate the deviation between the target vehicle speed and the actual vehicle speed; Based on the deviation, control the retarder braking torque according to the braking torque value. The braking torque value includes the slope compensation torque; Among them, the step of controlling the retarder braking torque based on the deviation and according to the braking torque value includes: Judge whether the deviation exceeds a preset value; If the deviation exceeds the value, control the retarder braking torque based on the slope compensation torque, including: comparing the retarder braking torque with the slope compensation torque to obtain a torque difference; adjusting the retarder braking torque according to the torque difference and the slope compensation torque; If the deviation does not exceed the value, control the retarder braking torque through a preset torque stabilization algorithm, including: obtaining a torque range based on the vehicle speed error between the target vehicle speed and the actual vehicle speed; controlling the retarder braking torque according to the torque range.

2. The torque control method according to claim 1, wherein After the step of starting the control program for the retarder braking torque, it further includes: Judge whether the preset electric braking circuit channel is safe; If the electric braking circuit channel is safe, execute the step of identifying the retarder gear to determine the retarder braking torque curve corresponding to the retarder gear and subsequent steps; If the electric braking circuit channel is not safe, turn off the retarder braking torque and give a warning prompt.

3. The torque control method according to claim 2, characterized in that, After the step of controlling the retarder braking torque based on the deviation and according to the braking torque value, it further includes: Return to execute the step of judging whether the preset electric braking circuit channel is safe.

4. The torque control method according to claim 1, wherein Before the step of starting the preset retarder braking torque, it further includes: Obtain the corresponding status information by receiving a preset status signal; Judge whether to execute the step of starting the preset control program and subsequent steps according to the status information.

5. A torque control device for implementing the torque control method according to any one of claims 1-4, characterized in that, The torque control device includes: A start module for starting the control program for the retarder braking torque; An identification module for identifying the retarder gear to determine the retarder braking torque curve corresponding to the retarder gear. The retarder braking torque curve includes a number of braking torque values and the target vehicle speeds corresponding to the braking torque values; A calculation module for obtaining the current actual vehicle speed and calculating the deviation between the target vehicle speed and the actual vehicle speed; A control module for controlling the retarder braking torque based on the deviation and according to the braking torque value.

6. A terminal device, characterized in that, The terminal device includes a memory, a processor, and a torque control program stored on the memory and executable on the processor. When the torque control program is executed by the processor, it implements the steps of the torque control method according to any one of claims 1-4.

7. A computer-readable storage medium, characterized in that, A torque control program is stored on the computer-readable storage medium. When the torque control program is executed by a processor, the steps of the torque control method according to any one of claims 1-4 are implemented.

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