Vehicle motor hill-holding control method and device

Abstract

The invention provides a vehicle motor hill-holding control method and device, and the method comprises the steps: determining a target torque of a target vehicle through closed-loop control with feedforward when an operation state signal of the target vehicle meets a preset hill-holding condition; the target torque is corrected according to the maximum positive increase amplitude of the target torque in unit time and the maximum negative decrease amplitude of the target torque in unit time, and the corrected torque is obtained; and controlling a motor of the target vehicle according to the corrected torque. By limiting the slope of the target torque, vehicle shaking caused by too large torque fluctuation can be effectively prevented, vehicle sliding can be prevented, and meanwhile the comfort of vehicle parking on the slope can be improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of vehicle control, in particular to a vehicle motor hill hold control method and device. BACKGROUND

[0002] In order to improve the safety and convenience of hill driving, most existing vehicles are equipped with a hill hold assist system. When the vehicle is parked or started on a slope, the hill hold assist system can replace the hand brake or foot brake to achieve the purpose of automatically maintaining the braking state and preventing the vehicle from rolling. For new energy vehicles such as pure electric or hybrid vehicles, the motor is usually used for hill hold control, because the motor hill hold control has the advantages of fast response and low energy consumption compared with the brake system hill hold.

[0003] The motor hill hold is to prevent the vehicle from rolling by rapid torque compensation, but too fast response can also resonate with the inherent vibration frequency of the vehicle transmission system, easily excite the inherent mechanical vibration mode of the system, and cause the vehicle to shake or surge. For example, when the hill hold is detected at the initial stage, the motor suddenly outputs a large torque, which will impact the transmission components like "pulling the reins", causing shaking; when switching from hill hold mode to drive mode, if the torque is not smoothly transitioned, surging will occur. Especially for commercial vehicles, due to the longer and more complex transmission chain, there are more transmission components from the motor to the wheels, and the cumulative inertia is large, which is more likely to cause forward and backward surging during hill hold control.

[0004] In summary, the existing motor hill hold control method can easily cause the vehicle to shake or surge, greatly reducing the comfort, and therefore there is an urgent need for a control method that can prevent the vehicle from rolling while considering the comfort of the vehicle hill hold. SUMMARY

[0005] The present application aims to solve at least one of the technical problems existing in the prior art, and provides a vehicle motor hill hold control method and device.

[0006] In a first aspect, the embodiments of the present application provide a vehicle motor hill hold control method, comprising:

[0007] When the running state signal of the target vehicle meets the preset hill hold condition, the target torque of the target vehicle is determined by closed-loop control with feedforward;

[0008] The target torque is corrected according to the positive maximum increment of the unit time target torque and the negative maximum decrement of the unit time target torque, to obtain a corrected torque;

[0009] The motor of the target vehicle is controlled according to the corrected torque.

[0010] Optionally, the target torque of the target vehicle is determined by closed-loop control with feedforward, comprising:

[0011] The target torque of the target vehicle is determined according to the following expression:

[0012] ;

[0013] wherein, Ttarget represents the target torque, Tff represents the feedforward torque, Tpid represents the PID closed-loop control torque;

[0014] The feedforward torque is obtained according to the following expression:

[0015] ;

[0016] wherein, m represents the total vehicle mass, g represents the gravity acceleration, represents the slope angle, represents the rolling resistance coefficient, represents the tire rolling radius.

[0017] Optionally, the target torque is corrected according to a positive maximum increment of the target torque per unit time and a negative maximum decrement of the target torque per unit time, comprising:

[0018] The target torque is corrected according to the following expression:

[0019]

[0020] wherein, Tcorrected represents the corrected torque, Ttarget represents the target torque at the current moment, Ttarget represents the target torque at the previous moment, represents the positive maximum increment of the target torque per unit time, represents the negative maximum decrement of the target torque per unit time.

[0021] Optionally, the method further comprises:

[0022] In response to the brake signal, when the brake pressure exceeds a brake pressure threshold or the brake pedal stroke exceeds a brake stroke threshold, the hill hold control is exited;

[0023] The target torque is corrected according to a positive maximum increment of the brake pedal torque and a negative maximum decrement of the brake pedal torque, so that the hill hold torque does not cause vehicle shaking when it is reduced to zero, the positive maximum increment of the brake pedal torque is calibrated when the brake pedal is exited in the downhill hill hold, and the negative maximum decrement of the brake pedal torque is calibrated when the brake pedal is exited in the uphill hill hold.

[0024] Optionally, the method further comprises:

[0025] In response to the accelerator signal, the hill hold control is exited when the accelerator opening exceeds an accelerator opening threshold or the accelerator pedal stroke exceeds an accelerator stroke threshold;

[0026] The target torque is corrected according to a positive maximum increase of the accelerator pedal torque and a negative maximum decrease of the accelerator pedal torque to prevent the vehicle from shaking when the hill hold torque decreases to the accelerator demand torque, the positive maximum increase of the accelerator pedal torque is calibrated when the accelerator pedal is exited on an uphill hill hold, and the negative maximum decrease of the accelerator pedal torque is calibrated when the accelerator pedal is exited on a downhill hill hold.

[0027] Optionally, the method further comprises:

[0028] The hill hold control is exited when the motor hill hold time is greater than a single longest hill hold time.

[0029] A driving torque less than the hill hold control demand torque is set, and the driving torque is corrected according to a positive maximum increase of the timeout exit torque and a negative maximum decrease of the timeout exit torque to prevent the vehicle from shaking when the hill hold control is exited due to timeout, the positive maximum increase of the timeout exit torque is calibrated when the hill hold control is exited due to timeout on a downhill hill hold, and the negative maximum decrease of the timeout exit torque is calibrated when the hill hold control is exited due to timeout on an uphill hill hold.

[0030] The hill hold control is re-entered when a current operating state signal of the target vehicle meets a preset hill hold condition, and the target torque is corrected according to a positive maximum increase of the re-enter hill hold torque after timeout and a negative maximum decrease of the re-enter hill hold torque after timeout to prevent the vehicle from shaking when the hill hold control is re-entered after timeout, the positive maximum increase of the re-enter hill hold torque after timeout is calibrated when the hill hold control is re-entered after timeout on an uphill hill hold, and the negative maximum decrease of the re-enter hill hold torque after timeout is calibrated when the hill hold control is re-entered after timeout on a downhill hill hold.

[0031] The timeout count is increased, and the above control process is repeated until the timeout count is greater than a maximum timeout hill hold number.

[0032] Optionally, the method further comprises:

[0033] The hill hold control is exited to enter a free state when the timeout count is greater than the maximum timeout hill hold number.

[0034] The target torque is corrected according to a positive maximum increase of the free state torque and a negative maximum decrease of the free state torque to prevent the vehicle from shaking when the hill hold control is exited to enter the free state, the positive maximum increase of the free state torque is calibrated when the hill hold control is exited to enter the free state on a downhill hill hold, and the negative maximum decrease of the free state torque is calibrated when the hill hold control is exited to enter the free state on an uphill hill hold.

[0035] In a second aspect, an embodiment of the present application provides a vehicle motor hill hold control device, comprising:

[0036] The processing module is used to determine the target torque of the target vehicle through closed-loop control with feedforward when the target vehicle's operating status signal meets the preset parking conditions.

[0037] The correction module is used to correct the target torque based on the maximum positive increase and the maximum negative decrease of the target torque per unit time, so as to obtain the corrected torque.

[0038] The control module is used to control the motor of the target vehicle based on the corrected torque.

[0039] Thirdly, the present invention provides an electronic device including a processor and a memory, the memory storing computer-readable instructions that, when executed by the processor, perform the steps of the method provided in the first aspect above.

[0040] Fourthly, the present invention provides a storage medium having a computer program stored thereon, which, when executed by a processor, performs the steps of the method provided in the first aspect above.

[0041] Fifthly, the present invention provides a computer program product comprising a computer program that, when executed by a processor, performs the steps of the method provided in the first aspect above.

[0042] As can be seen from the above technical solutions, the present invention has the following advantages:

[0043] This invention provides a vehicle motor hill-dwelling control method and apparatus. When the target vehicle's operating status signal meets preset hill-dwelling conditions, the target torque of the target vehicle is determined through closed-loop control with feedforward. The target torque is corrected based on the maximum positive increase and maximum negative decrease of the target torque per unit time to obtain the corrected torque. The target vehicle's motor is then controlled based on the corrected torque. By limiting the slope of the target torque, vehicle vibration caused by excessive torque fluctuations can be effectively prevented, thus improving the comfort of hill-dwelling while preventing vehicle slippage. Attached Figure Description

[0044] Figure 1 This is a flowchart illustrating a first embodiment of a vehicle motor hill-start control method according to the present invention;

[0045] Figure 2 This is a flowchart illustrating a second embodiment of the vehicle motor hill-start control method of the present invention;

[0046] Figure 3 This is a schematic diagram illustrating the motor speed and torque control after a pause in the uphill slope according to the present invention;

[0047] Figure 4This is a structural block diagram of an embodiment of a vehicle motor hill-start control device according to the present invention;

[0048] Figure 5 This is a structural block diagram of an electronic device provided in an embodiment of the present invention. Detailed Implementation

[0049] To enable those skilled in the art to better understand the technical solutions of the present invention, exemplary embodiments of the present invention are described below in conjunction with the accompanying drawings, including various details of the embodiments of the present invention to aid understanding. These should be considered merely exemplary. Therefore, those skilled in the art should recognize that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of the present invention. Similarly, for clarity and brevity, descriptions of well-known functions and structures are omitted in the following description.

[0050] Where there is no conflict, the various embodiments of the present invention and the features thereof may be combined with each other.

[0051] As used herein, the term “and / or” includes any and all combinations of one or more related enumerated entries.

[0052] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the invention. As used herein, the singular forms “a” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will also be understood that when the terms “comprising” and / or “made of” are used in this specification, the presence of the stated feature, integral, step, operation, element, and / or component is specified, but the presence or addition of one or more other features, integrals, steps, operations, elements, components, and / or groups thereof is not excluded. Terms such as “connected” or “linked” are not limited to physical or mechanical connections but can include electrical connections, whether direct or indirect.

[0053] Unless otherwise specified, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art. It will also be understood that terms such as those defined in commonly used dictionaries should be interpreted as having the meaning consistent with their meaning in the context of the relevant art and the invention, and will not be interpreted as having an idealized or overly formal meaning unless expressly so defined herein.

[0054] In the technical solution of this invention, the collection, storage, use, processing, transmission, provision, and disclosure of user personal information all comply with relevant laws and regulations and do not violate public order and good morals. The use of user data in this technical solution follows relevant national laws and regulations (e.g., the "Information Security Technology - Personal Information Security Specification"). For example: appropriate measures are taken for personal information access control; restrictions are imposed on the display of personal information; the purpose of using personal information does not exceed the scope of direct or reasonable association; and explicit identity targeting is eliminated when using personal information to avoid precisely locating a specific individual.

[0055] Figure 1 This is a schematic flowchart of an embodiment of a vehicle motor hill-start control method according to the present invention. Figure 1 As shown, the vehicle motor hill-start control method provided in this embodiment may include:

[0056] Step S101: When the operating status signal of the target vehicle meets the preset parking conditions, the target torque of the target vehicle is determined by closed-loop control with feedforward.

[0057] Vehicle operating status signals are a set of signals that reflect the real-time operating status of the vehicle. Preset hill-holding conditions are used to determine whether the vehicle needs hill-holding control. In this embodiment, the following conditions must be met simultaneously to trigger the hill-holding function: the vehicle is in start mode; the accelerator and brake pedals are released; the motor speed direction is opposite to the driving wheel direction, and this direction exceeds a speed threshold for a sustained period; the slope is greater than a slope threshold. It should be noted that in this embodiment, "the motor speed direction is opposite to the driving wheel direction" includes the following situations: the vehicle is in drive gear, but the motor speed direction is opposite to the driving direction; or the vehicle is in reverse gear, but the motor speed direction is opposite to the reversing direction. The duration is a calibrated value; it cannot be too large, otherwise it will not be able to detect vehicle rollback in time, nor too small, otherwise it will mistakenly enter hill-holding control. It is generally set to 0.3~0.8 seconds. The speed threshold is also a calibrated value, which can be set by observing the wheel rollback distance or subjectively feeling the vehicle rollback. It is generally set to 50~200 rpm. The slope threshold is generally set to 3%-5%. If the vehicle has no slope signal, this condition can be ignored.

[0058] In one optional implementation, the target torque of the target vehicle is determined through closed-loop control with feedforward, specifically including:

[0059] The target torque of the target vehicle is determined using the following expression:

[0060] ;

[0061] in, Indicates the target torque. Indicates feedforward torque. This indicates the torque of a Proportional-Integral-Derivative (PID) closed-loop control.

[0062] The feedforward torque is obtained using the following expression:

[0063] ;

[0064] in, Indicates the overall vehicle weight. Represents gravitational acceleration. Indicates the slope angle. Indicates the rolling resistance coefficient. This indicates the tire rolling radius. It should be noted that if accurate vehicle weight and gradient signals are unavailable, the feedforward torque can be calibrated, for example, by setting a baseline value. 20N can be selected. m-100N m.

[0065] Step S102: Correct the target torque based on the maximum positive increase and the maximum negative decrease of the target torque per unit time to obtain the corrected torque.

[0066] To avoid vehicle vibration caused by excessive torque fluctuations, this embodiment needs to limit the target torque slope after entering the parking slope to reduce torque fluctuations.

[0067] In one optional implementation, the target torque is corrected based on the maximum positive increase and the maximum negative decrease of the target torque per unit time, which may specifically include:

[0068] The target torque is corrected according to the following expression:

[0069]

[0070] in, This indicates the corrected torque. This represents the target torque at the current moment. This indicates the target torque at the previous moment. This indicates the maximum positive increase in the target torque per unit time. This indicates the maximum negative reduction in the target torque per unit time.

[0071] Step S103: Control the motor of the target vehicle according to the corrected torque.

[0072] In this embodiment, after obtaining the corrected torque, the motor of the target vehicle can be controlled according to the corrected torque to enable the target vehicle to park on the slope.

[0073] The vehicle motor hill-dwelling control method provided in this embodiment determines the target torque of the target vehicle through closed-loop control with feedforward when the target vehicle's operating status signal meets the preset hill-dwelling conditions. The target torque is then corrected based on the maximum positive increase and maximum negative decrease of the target torque per unit time, resulting in a corrected torque. The target vehicle's motor is controlled according to this corrected torque. By limiting the slope of the target torque, vehicle vibration caused by excessive torque fluctuations can be effectively prevented, thus improving hill-dwelling comfort while preventing vehicle slippage.

[0074] Based on the above embodiments, in order to further improve the comfort of vehicle parking on slopes, this embodiment provides a more targeted torque slope control method for different scenarios.

[0075] For scenarios where the preset slope-entry conditions are met, then... This indicates the maximum positive torque increase when entering a parking slope. The setting can be based on the torque slope when starting at full throttle on a flat road, taking a 1ms calculation cycle as an example. 0.5N can be used. m ~ 1.5N m; with This indicates the maximum negative torque reduction when entering a parking slope. The setting can be based on the torque slope of a full-throttle reverse start on a flat road, taking a 1ms calculation cycle as an example. -1.5N can be used. m ~-0.5N m. According to and Correcting the target torque can reduce torque fluctuations when entering a parking slope scenario, preventing the vehicle from rolling back and improving the comfort of parking on a slope.

[0076] When the target vehicle receives a braking signal, such as brake pressure or brake pedal travel, and this signal exceeds a brake pressure threshold or brake travel threshold, the vehicle is determined to have disengaged from hill-start assist due to braking. It is particularly important to emphasize that these brake pressure or brake travel thresholds need to be sufficiently high to ensure that the vehicle can maintain its position without rolling back due to the braking system.

[0077] For scenarios where parking control is disengaged by applying the brake, the vehicle motor parking control method provided in this embodiment may further include: responding to a brake signal, disengaging parking control when the brake pressure exceeds a brake pressure threshold or the brake pedal travel exceeds a brake travel threshold; correcting the target torque based on the maximum positive increase and the maximum negative decrease of the brake torque to ensure that the parking torque does not cause vehicle vibration when it drops to zero; the maximum positive increase of the brake torque is calibrated when disengaging parking control on a downhill slope, and the maximum negative increase of the brake torque is calibrated when disengaging parking control on an uphill slope.

[0078] The condition for disengaging hill-hold control by applying the brakes is that the actual torque of the motor is zero. To prevent vehicle vibration caused by a rapid drop in hill-hold torque after disengaging, it is necessary to adjust the braking torque based on the maximum positive increase. Maximum negative reduction in braking torque The target torque is corrected. Calibration is performed when disengaging the brakes while parking on an uphill slope. Calibration when parking on a downhill slope and applying the brakes to exit. The calibration target is to prevent vehicle vibration when the parking torque drops to zero. Taking a 1ms calculation cycle as an example... Generally, 1N is taken. m ~ 2N m, Generally, -2N is taken. m ~ -1Nm.

[0079] When the target vehicle receives a throttle signal, such as throttle opening or travel, and the throttle opening or travel threshold is exceeded, it is determined that the vehicle has disengaged from hill-start assist due to throttle input. It is particularly important to emphasize that the throttle opening or travel threshold must be sufficiently large to ensure that the driving force exceeds the hill-start assist torque. In an alternative implementation, "driving force exceeding hill-start assist torque" can also be directly used as the criterion for determining whether the vehicle has disengaged from hill-start assist due to throttle input.

[0080] For scenarios where hill-start assist is disengaged by pressing the accelerator pedal, the vehicle motor hill-start assist method provided in this embodiment may further include: responding to the accelerator signal, disengaging hill-start assist when the accelerator opening exceeds a accelerator opening threshold or the accelerator pedal travel exceeds a accelerator travel threshold; correcting the target torque based on the maximum positive increase and the maximum negative decrease of the accelerator torque to ensure that the hill-start assist torque is reduced to the accelerator torque requirement without causing vehicle vibration, wherein the maximum positive increase of the accelerator torque is calibrated when disengaging hill-start assist on an uphill slope, and the maximum negative increase of the accelerator torque is calibrated when disengaging hill-start assist on a downhill slope.

[0081] The condition for disengaging hill hold control by pressing the accelerator is that the actual torque of the motor equals the torque required by pressing the accelerator. To prevent vehicle vibration caused by the motor torque increasing too quickly after disengaging hill hold, it is necessary to consider the maximum positive increase in torque when pressing the accelerator. Maximum negative torque reduction when pressing the accelerator pedal The target torque is corrected. Calibration is performed when disengaging the accelerator while holding the vehicle uphill. When exiting a downhill slope by pressing the accelerator, the calibration is performed. The calibration target is to prevent vehicle vibration when the parking torque drops to the torque required by the throttle. Taking a 1ms calculation cycle as an example... Generally, 1.2N is taken. m~2.2N m, Generally, -2.2N is taken. m ~ -1.2N m.

[0082] In summary, this application provides different torque control flexible processing methods for scenarios of entering the parking slope under preset parking conditions, exiting the parking slope control by pressing the brake, and exiting the parking slope control by pressing the accelerator. These methods achieve smooth parking slope control, reduce the backward roll distance, and further improve the comfort of the vehicle when parking on a slope.

[0083] Once the target vehicle achieves hill-holding control via motor control, if the driver does not apply the brakes or accelerator for an extended period, the vehicle will remain in the motor-controlled hill-holding state. This not only increases energy consumption but also risks overheating and damage to the motor due to prolonged operation. To avoid energy loss and overheating of the motor, this application further provides a corresponding torque control strategy for prolonged hill-holding scenarios.

[0084] For scenarios involving prolonged hill-climbing, the vehicle motor hill-climbing control method provided in this embodiment may further include:

[0085] When the motor's parking time exceeds the longest single parking time, parking control is discontinued.

[0086] Set a drive torque that is less than the required torque for hill hold control, and correct the drive torque according to the maximum positive increase and the maximum negative decrease of the timeout exit torque, so that the vehicle will not vibrate when exiting the hill hold after the timeout. The maximum positive increase of the timeout exit torque is calibrated when exiting the hill hold after the timeout on a downhill slope, and the maximum negative increase of the timeout exit torque is calibrated when exiting the hill hold after the timeout on an uphill slope.

[0087] When the target vehicle's current operating status signal meets the preset parking conditions, it re-enters parking control. The target torque is then corrected based on the maximum positive increase and maximum negative decrease of the parking torque after the timeout, so that the vehicle does not vibrate when re-entering parking after the timeout. The maximum positive increase of the parking torque after the timeout is calibrated when re-entering parking after the timeout on an uphill slope, and the maximum negative increase of the parking torque after the timeout is calibrated when re-entering parking after the timeout on a downhill slope.

[0088] Increase the timeout count and repeat the above control process until the timeout count is greater than the maximum number of timeouts for sloping.

[0089] In one optional implementation, when the timeout count exceeds the maximum number of timeouts for hill-holding, the hill-holding control is exited and the vehicle enters a free state. The target torque is corrected based on the maximum positive increase and the maximum negative decrease of the free state torque to prevent vehicle vibration when exiting the hill-holding control and entering the free state. The maximum positive increase of the free state torque is calibrated when exiting the hill-holding control and entering the free state on a downhill slope, and the maximum negative increase of the free state torque is calibrated when exiting the hill-holding control and entering the free state on an uphill slope.

[0090] For handling cases where the stationing time exceeds the limit, please refer to the following: Figure 2 As shown, Figure 2 This is a flowchart illustrating a second embodiment of the vehicle motor hill-holding control method of the present invention. After the motor hill-holding control is initiated, the hill-holding time is timed. The longest single hill-holding time is used to determine whether the hill-holding has exceeded the time limit. If the time limit is exceeded, the hill-holding control is terminated. If the hill-holding control is re-entered for reasons other than timeout, the timeout count needs to be reset to zero.

[0091] If the hill-holding control is disengaged due to timeout, the vehicle will roll back downhill and quickly enter the next hill-holding control phase if the driver does not apply the brakes or accelerator. To reduce the drastic changes in control torque, it is necessary to set a drive torque that is less than the hill-holding torque, and also to set a limit value for the slope of the timeout hill-holding torque.

[0092] Drive torque You can set it using the following expression. ,in The torque required for the previous hill-start assist was [not specified]. To reduce the coefficient, which allows the vehicle to roll back after exiting the hill while maintaining a relatively small change in driving torque, a value of 0.5 to 0.8 can be used. This can be determined based on the maximum positive increase in the timeout exit torque. and the maximum negative reduction of torque after timeout The drive torque is adjusted to avoid vibration. Among other things, It needs to be calibrated when exiting the hillside after exceeding the time limit. Calibration is required when exiting the parking position after exceeding the timeout period on a downhill slope. The calibration goal is to prevent vehicle vibration during this process. Taking a 1ms calculation cycle as an example... 1.4N can be selected. m~2.4N m, -2.4N can be taken. m ~ -1.4N m.

[0093] Based on preset parking conditions, it is determined whether to re-enter parking control. If so, the parking timer is reset, feedforward torque is set, torque slope limit is set, and the timeout count is increased by one. During the timeout period between exiting and re-entering parking, the vehicle conditions (vehicle weight, slope) remain essentially unchanged, and the required parking torque is basically the same. To ensure efficient closed-loop parking control of the motor upon re-entry, the previous parking torque is used as the feedforward torque for this parking control. Furthermore, the maximum positive increase in parking torque upon re-entry after the timeout is calculated. And the maximum negative reduction in torque after the timeout and subsequent re-entry on the slope The target torque is adjusted to avoid vehicle vibration. The calibration needs to be performed when re-entering the hill after exceeding the uphill time limit. Calibration is required when re-entering the parking slope after a timeout on the downhill section. The calibration goal is to prevent vehicle vibration when re-entering the parking slope after a timeout. Taking a 1ms calculation cycle as an example... 1.4N can be selected. m ~ 2.4N m, -2.4N can be taken. m ~ -1.4N m.

[0094] The above strategy is followed in a loop until the number of timeouts exceeds the maximum number of timeouts for hill-climbing. When the number of timeouts exceeds the maximum number of timeouts for hill-climbing, hill-climbing control is exited, a torque slope limit is set, the number of timeouts is initialized to zero, and the feedforward torque is also initialized. Further, the maximum positive increase in torque is determined based on the exit from hill-climbing and entry into a free state. The maximum negative reduction after exiting the stationed position and entering a free state. The target torque is corrected. The calibration is performed when exiting the hill and entering a free state. The calibration is performed when exiting the parking position and entering a free-running state on a downhill slope. The calibration goal is to prevent vehicle vibration during this process. Taking a 1ms calculation cycle as an example... 0.8N can be used. m ~ 1.8N m, -1.8N can be used. m ~ -0.8N m.

[0095] It should be noted that the maximum single-time hill-holding time and the maximum number of overtime hill-holding attempts need to be determined based on factors such as the target vehicle's motor power generation characteristics, maximum roll-off distance, and the driver's hill-holding time requirements. For example, the maximum single-time hill-holding time can be taken as 5 to 10 seconds, and the maximum number of overtime hill-holding attempts can be taken as 2 to 4 times.

[0096] Taking a maximum of 3 times the maximum timeout for hill-climbing as an example, the motor speed and torque control after the timeout during uphill sloping can be referenced. Figure 3 . Figure 3 This is a schematic diagram illustrating the motor speed and torque control after a parking timeout during uphill driving, according to the present invention. Figure 3 As shown, after more than 3 hill-hold attempts, the hill-hold control is disengaged, and the vehicle will no longer automatically enter the hill-hold function, but will be in a free state.

[0097] Based on any of the above embodiments, the vehicle motor hill-start control method provided in this embodiment further provides a corresponding torque slope control method for overtime hill-start scenarios, which not only improves the comfort of the vehicle when hill-start, but also avoids motor energy loss and motor overheating, improves motor efficiency, and extends motor life.

[0098] Figure 4 This is a structural block diagram of an embodiment of a vehicle motor hill-start control device according to the present invention. Figure 4 The vehicle motor hill-start control device provided in this embodiment may include: a processing module 401, a correction module 402, and a control module 403.

[0099] The processing module 401 is used to determine the target torque of the target vehicle through closed-loop control with feedforward when the operating status signal of the target vehicle meets the preset parking conditions.

[0100] Correction module 402 is used to correct the target torque based on the maximum positive increase and the maximum negative decrease of the target torque per unit time, so as to obtain the corrected torque.

[0101] Control module 403 is used to control the motor of the target vehicle according to the corrected torque.

[0102] The apparatus of this embodiment can be used to perform Figure 1 The technical solutions of the method embodiments shown are similar in principle and in effect, and will not be described again here.

[0103] In one optional implementation, the processing module 401 is used to determine the target torque of the target vehicle through closed-loop control with feedforward, specifically including:

[0104] The target torque of the target vehicle is determined using the following expression:

[0105] ;

[0106] in, Indicates the target torque. Indicates feedforward torque. This indicates the torque under PID closed-loop control.

[0107] The feedforward torque is obtained using the following expression:

[0108] ;

[0109] in, Indicates the overall vehicle weight. Represents gravitational acceleration. Indicates the slope angle. Indicates the rolling resistance coefficient. This indicates the tire's rolling radius.

[0110] In one optional implementation, the correction module 402 is used to correct the target torque based on the maximum positive increase and the maximum negative decrease of the target torque per unit time, specifically including:

[0111] The target torque is corrected according to the following expression:

[0112]

[0113] in, This indicates the corrected torque. This represents the target torque at the current moment. This indicates the target torque at the previous moment. This indicates the maximum positive increase in the target torque per unit time. This indicates the maximum negative reduction in the target torque per unit time.

[0114] In one optional implementation, the vehicle motor hill-start control device may further include a brake disengagement control module for:

[0115] In response to a braking signal, hill-start assist is disengaged when the braking pressure exceeds the braking pressure threshold or the brake pedal travel exceeds the braking travel threshold.

[0116] The target torque is corrected based on the maximum positive increase and the maximum negative decrease of the braking torque to ensure that the vehicle does not vibrate when the parking torque drops to zero. The maximum positive increase of the braking torque is calibrated when parking downhill and disengaging the brakes, while the maximum negative increase of the braking torque is calibrated when parking uphill and disengaging the brakes.

[0117] In one optional implementation, the vehicle motor hill-start control device may further include an accelerator pedal disengagement control module, used for:

[0118] In response to the throttle signal, when the throttle opening exceeds the throttle opening threshold or the throttle pedal travel exceeds the throttle travel threshold, the hill-start assist control is disengaged.

[0119] The target torque is corrected based on the maximum positive increase and the maximum negative decrease of the accelerator torque to ensure that the vehicle does not vibrate when the parking torque drops to the torque required by the accelerator. The maximum positive increase of the accelerator torque is calibrated when parking uphill and disengaging the accelerator, and the maximum negative increase of the accelerator torque is calibrated when parking downhill and disengaging the accelerator.

[0120] In one optional implementation, the vehicle motor hill-start control device may further include a timeout control module for:

[0121] When the motor's parking time exceeds the longest single parking time, parking control is discontinued.

[0122] Set a drive torque that is less than the required torque for hill hold control, and correct the drive torque according to the maximum positive increase and the maximum negative decrease of the timeout exit torque, so that the vehicle will not vibrate when exiting the hill hold after the timeout. The maximum positive increase of the timeout exit torque is calibrated when exiting the hill hold after the timeout on a downhill slope, and the maximum negative increase of the timeout exit torque is calibrated when exiting the hill hold after the timeout on an uphill slope.

[0123] When the target vehicle's current operating status signal meets the preset parking conditions, it re-enters parking control. The target torque is then corrected based on the maximum positive increase and maximum negative decrease of the parking torque after the timeout, so that the vehicle does not vibrate when re-entering parking after the timeout. The maximum positive increase of the parking torque after the timeout is calibrated when re-entering parking after the timeout on an uphill slope, and the maximum negative increase of the parking torque after the timeout is calibrated when re-entering parking after the timeout on a downhill slope.

[0124] Increase the timeout count and repeat the above control process until the timeout count is greater than the maximum number of timeouts for sloping.

[0125] In one optional implementation, the timeout control module is further configured to:

[0126] When the timeout count exceeds the maximum number of timeouts for slope holding, the slope holding control is exited and the system enters a free state.

[0127] The target torque is corrected based on the maximum positive increase and the maximum negative decrease of the free state torque to prevent vehicle vibration when exiting hill hold control and entering free state. The maximum positive increase of the free state torque is calibrated when exiting hill hold control and entering free state on a downhill slope, and the maximum negative increase of the free state torque is calibrated when exiting hill hold control and entering free state on an uphill slope.

[0128] Based on the same inventive concept, embodiments of the present invention also provide an electronic device. Figure 5 This is a structural block diagram of an electronic device provided in an embodiment of the present invention. Figure 5 As shown, an embodiment of the present invention provides an electronic device including: one or more processors 101, a memory 102, and one or more I / O interfaces 103. The memory 102 stores one or more programs, which, when executed by the one or more processors, cause the one or more processors to implement any of the vehicle motor hill-start control methods described in the above embodiments; the one or more I / O interfaces 103 are connected between the processors and the memory, configured to enable information interaction between the processors and the memory.

[0129] The processor 101 is a device with data processing capabilities, including but not limited to a central processing unit (CPU); the memory 102 is a device with data storage capabilities, including but not limited to random access memory (RAM, more specifically SDRAM, DDR, etc.), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), and flash memory (FLASH); the I / O interface (read / write interface) 103 is connected between the processor 101 and the memory 102, and can realize information interaction between the processor 101 and the memory 102, including but not limited to a data bus (Bus).

[0130] In some embodiments, the processor 101, memory 102, and I / O interface 103 are interconnected via bus 104, and thus connected to other components of the computing device.

[0131] In some embodiments, the one or more processors 101 include a field-programmable gate array.

[0132] It should be noted that the electronic device provided in this embodiment can be applied to new energy vehicles such as pure electric or hybrid vehicles.

[0133] This invention also provides a computer-readable medium. The computer-readable medium stores a computer program, which, when executed by a processor, implements the steps of any of the vehicle motor hill-start control methods described in the above embodiments. The computer-readable storage medium may be volatile or non-volatile.

[0134] This invention also provides a computer program product, including computer-readable code, or a non-volatile computer-readable storage medium carrying computer-readable code. When the computer-readable code is run in the processor of an electronic device, the processor in the electronic device executes the above-described vehicle motor hill-start control method.

[0135] Those skilled in the art will understand that all or some of the steps, systems, and apparatuses disclosed above, and their functional modules / units, can be implemented as software, firmware, hardware, or suitable combinations thereof. In hardware implementations, the division between functional modules / units mentioned above does not necessarily correspond to the division of physical components; for example, a physical component may have multiple functions, or a function or step may be performed collaboratively by several physical components. Some or all physical components may be implemented as software executed by a processor, such as a central processing unit, digital signal processor, or microprocessor, or as hardware, or as an integrated circuit, such as an application-specific integrated circuit (ASIC). Such software can be distributed on a computer-readable storage medium, which may include computer storage media (or non-transitory media) and communication media (or transient media).

[0136] As is known to those skilled in the art, the term computer storage medium includes volatile and non-volatile, removable and non-removable media implemented in any method or technology for storing information, such as computer-readable program instructions, data structures, program modules, or other data. Computer storage media includes, but is not limited to, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM), static random access memory (SRAM), flash memory or other memory technologies, portable compact disc read-only memory (CD-ROM), digital versatile disc (DVD) or other optical disc storage, magnetic cartridges, magnetic tape, disk storage or other magnetic storage devices, or any other medium that can be used to store desired information and is accessible to a computer. Furthermore, it is known to those skilled in the art that communication media typically contain computer-readable program instructions, data structures, program modules, or other data in modulated data signals such as carrier waves or other transmission mechanisms, and may include any information delivery medium.

[0137] The computer-readable program instructions described herein can be downloaded from computer-readable storage media to various computing / processing devices, or downloaded via a network, such as the Internet, local area network, wide area network, and / or wireless network, to an external computer or external storage device. The network may include copper transmission cables, fiber optic transmission, wireless transmission, routers, firewalls, switches, gateway computers, and / or edge servers. A network adapter card or network interface in each computing / processing device receives the computer-readable program instructions from the network and forwards them to the computer-readable storage media in the respective computing / processing device.

[0138] The computer program instructions used to perform the operations of this invention may be assembly instructions, instruction set architecture (ISA) instructions, machine instructions, machine-dependent instructions, microcode, firmware instructions, state setting data, or source code or object code written in any combination of one or more programming languages, including object-oriented programming languages ​​such as Smalltalk, C++, etc., and conventional procedural programming languages ​​such as the "C" language or similar programming languages. The computer-readable program instructions may be executed entirely on the user's computer, partially on the user's computer, as a standalone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving a remote computer, the remote computer may be connected to the user's computer via any type of network—including a local area network (LAN) or a wide area network (WAN)—or may be connected to an external computer (e.g., via the Internet using an Internet service provider). In some embodiments, electronic circuitry, such as programmable logic circuitry, field-programmable gate arrays (FPGAs), or programmable logic arrays (PLAs), is personalized by utilizing state information from the computer-readable program instructions. This electronic circuitry can execute the computer-readable program instructions to implement various aspects of the invention.

[0139] The computer program product described herein can be implemented specifically through hardware, software, or a combination thereof. In one alternative embodiment, the computer program product is specifically embodied in a computer storage medium; in another alternative embodiment, the computer program product is specifically embodied in a software product, such as a software development kit (SDK), etc.

[0140] Various aspects of the present invention are described herein with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It should be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer-readable program instructions.

[0141] These computer-readable program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing apparatus to produce a machine such that, when executed by the processor of the computer or other programmable data processing apparatus, they create means for implementing the functions / actions specified in one or more blocks of the flowchart and / or block diagram. These computer-readable program instructions can also be stored in a computer-readable storage medium that causes a computer, programmable data processing apparatus, and / or other device to operate in a particular manner; thus, the computer-readable medium storing the instructions comprises an article of manufacture that includes instructions for implementing aspects of the functions / actions specified in one or more blocks of the flowchart and / or block diagram.

[0142] Computer-readable program instructions may also be loaded onto a computer, other programmable data processing apparatus, or other device to cause a series of operational steps to be performed on the computer, other programmable data processing apparatus, or other device to produce a computer-implemented process, thereby causing the instructions executed on the computer, other programmable data processing apparatus, or other device to perform the functions / actions specified in one or more boxes of a flowchart and / or block diagram.

[0143] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of the present invention. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of an instruction, which contains one or more executable instructions for implementing a specified logical function. In some alternative implementations, the functions marked in the blocks may occur in a different order than those shown in the drawings. For example, two consecutive blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, may be implemented using a dedicated hardware-based system that performs the specified function or action, or using a combination of dedicated hardware and computer instructions.

[0144] Example embodiments have been disclosed herein, and while specific terminology has been used, it is for illustrative purposes only and should be construed as such, and is not intended to be limiting. In some instances, it will be apparent to those skilled in the art that features, characteristics, and / or elements described in conjunction with particular embodiments may be used alone, or in combination with features, characteristics, and / or elements described in conjunction with other embodiments, unless otherwise expressly indicated. Therefore, those skilled in the art will understand that various changes in form and detail may be made without departing from the scope of the invention as set forth in the appended claims.

Claims

1. A method for controlling vehicle motor parking slope, characterized in that, include: When the operating status signal of the target vehicle meets the preset parking conditions, the target torque of the target vehicle is determined by closed-loop control with feedforward. The target torque is corrected based on the maximum positive increase and the maximum negative decrease of the target torque per unit time to obtain the corrected torque; The target vehicle's motor is controlled according to the modified torque.

2. The method according to claim 1, characterized in that, Determining the target torque of the target vehicle through closed-loop control with feedforward includes: The target torque of the target vehicle is determined according to the following expression: ； in, Indicates the target torque. Indicates feedforward torque. This indicates the torque under PID closed-loop control. The feedforward torque is obtained through the following expression: ； in, Indicates the overall vehicle weight. Represents gravitational acceleration. Indicates the slope angle. Indicates the rolling resistance coefficient. This indicates the tire's rolling radius.

3. The method according to claim 1, characterized in that, The step of correcting the target torque based on the maximum positive increase and the maximum negative decrease of the target torque per unit time includes: The target torque is corrected according to the following expression: in, This indicates the corrected torque. This represents the target torque at the current moment. This indicates the target torque at the previous moment. This indicates the maximum positive increase in the target torque per unit time. This indicates the maximum negative reduction in the target torque per unit time.

4. The method according to claim 1, characterized in that, The method further includes: In response to a braking signal, hill-start assist is disengaged when the braking pressure exceeds the braking pressure threshold or the brake pedal travel exceeds the braking travel threshold. The target torque is corrected based on the maximum positive increase and the maximum negative decrease of the braking torque to ensure that the vehicle does not vibrate when the parking torque drops to zero. The maximum positive increase of the braking torque is calibrated when parking downhill and disengaging the brakes, and the maximum negative increase of the braking torque is calibrated when parking uphill and disengaging the brakes.

5. The method according to claim 1, characterized in that, The method further includes: In response to the throttle signal, when the throttle opening exceeds the throttle opening threshold or the throttle pedal travel exceeds the throttle travel threshold, the hill-start assist control is disengaged. The target torque is corrected based on the maximum positive increase and the maximum negative decrease of the accelerator torque to ensure that the vehicle does not vibrate when the parking torque drops to the torque required by the accelerator. The maximum positive increase of the accelerator torque is calibrated when exiting the accelerator while parking uphill, and the maximum negative increase of the accelerator torque is calibrated when exiting the accelerator while parking downhill.

6. The method according to any one of claims 1-5, characterized in that, The method further includes: When the motor's parking time exceeds the longest single parking time, parking control is discontinued. Set a drive torque less than the required torque for hill-holding control, and correct the drive torque according to the maximum positive increase and the maximum negative decrease of the timeout exit torque, so as not to cause vehicle vibration when exiting hill-holding over time. The maximum positive increase of the timeout exit torque is calibrated when exiting hill-holding over time on a downhill slope, and the maximum negative increase of the timeout exit torque is calibrated when exiting hill-holding over time on an uphill slope. When the current operating status signal of the target vehicle meets the preset parking conditions, the parking control is re-entered, and the target torque is corrected according to the maximum positive increase of the parking torque after timeout and the maximum negative decrease of the parking torque after timeout, so as not to cause vehicle vibration when re-entering the parking position after timeout. The maximum positive increase of the parking torque after timeout is calibrated when re-entering the parking position after timeout on an uphill slope, and the maximum negative increase of the parking torque after timeout is calibrated when re-entering the parking position after timeout on a downhill slope. Increase the timeout count and repeat the above control process until the timeout count is greater than the maximum number of timeouts for sloping.

7. The method according to claim 6, characterized in that, The method further includes: When the timeout count exceeds the maximum number of timeouts for slope holding, the slope holding control is exited and the system enters a free state. The target torque is corrected based on the maximum positive increase and the maximum negative decrease of the free state torque to prevent vehicle vibration when exiting hill hold control and entering free state. The maximum positive increase of the free state torque is calibrated when exiting hill hold control and entering free state on a downhill slope, and the maximum negative increase of the free state torque is calibrated when exiting hill hold control and entering free state on an uphill slope.

8. A vehicle motor hill-start control device, characterized in that, include: The processing module is used to determine the target torque of the target vehicle through closed-loop control with feedforward when the operating status signal of the target vehicle meets the preset parking conditions. The correction module is used to correct the target torque based on the maximum positive increase and the maximum negative decrease of the target torque per unit time, so as to obtain the corrected torque. A control module is used to control the motor of the target vehicle according to the corrected torque.

9. An electronic device, characterized in that, include: One or more processors; Memory, used to store one or more programs; When the one or more programs are executed by the one or more processors, the one or more processors implement the method as described in any one of claims 1 to 7.

10. A computer-readable medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the steps of the method as described in any one of claims 1 to 7.

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