Target vehicle control method and device, storage medium and computer program product

Abstract

The invention discloses a control method and device of a target vehicle, a storage medium and a computer program product, and relates to the field of vehicles, and the control method of the target vehicle comprises the steps that under the condition that it is determined that the target vehicle is in a sliding state, the maximum demand negative torque of the target vehicle is determined according to the driving intention of a target object; according to the required negative torques of the target vehicle at different moments, motor negative torques output by a motor of the target vehicle are adjusted; when it is determined that the difference value between the first motor negative torque output by the motor at the first moment and the maximum motor negative torque of the motor is smaller than a first threshold value, a brake hydraulic starting signal is sent to a brake hydraulic controller at the first moment; and in the first time period, second motor negative torques output by the motor at different moments are adjusted according to the actual hydraulic execution values of the hydraulic negative torques at different moments, so that the absolute value of the difference value between the execution negative torques and the required negative torques of the target vehicle at different moments in the first time period is controlled to be smaller than a second threshold value.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of vehicles, in particular to a target vehicle control method and device, a storage medium and a computer program product. BACKGROUND

[0002] Electric vehicles, including pure electric vehicles and hybrid vehicles, have gradually begun to occupy the mainstream market of automobile sales. Compared with traditional vehicles, when the driver releases the brake pedal, the electric motor can recover battery energy to reduce energy consumption and provide deceleration effect through drag. However, in the case of limited charging power such as near full battery or extremely low temperature, the electric motor cannot provide sufficient drag torque when the vehicle is coasting, which cannot guarantee the consistency of coasting energy recovery driving experience and cannot guarantee the normal function of single-pedal deceleration. The inconsistency of driving experience may confuse the user.

[0003] In order to ensure the consistency of the driver's driving experience in the coasting energy recovery mode, there is currently a method to compensate for the deceleration demand that the electric motor cannot meet through brake hydraulic pressure, ensuring that even if the charging power is limited, although the brake pedal is not pressed, the vehicle can still achieve the expected deceleration by executing brake hydraulic pressure. However, due to the response time and execution accuracy of brake hydraulic pressure being much lower than the execution effect of electric motor torque, this results in that although the vehicle can ultimately achieve the expected deceleration effect, there is a sense of interruption and delay in the deceleration establishment process, and the actual deceleration establishment shape is uncertain. In addition, the current interaction between most vehicle electric motor torque controllers and brake hydraulic pressure controllers requires network communication, and communication delay will further worsen the interaction effect of electric motor torque and brake hydraulic pressure, and in severe cases, it may even result in a driving experience that is not as good as not compensating for brake hydraulic pressure in the case of limited charging capacity in the coasting energy recovery mode.

[0004] In view of the problems in the prior art that the brake hydraulic compensation technology has slow response time, low execution accuracy and communication delay, which seriously affects the driving experience of the driver during the coasting energy recovery process of the vehicle, an effective solution has not yet been proposed. SUMMARY

[0005] The embodiments of the present application provide a target vehicle control method and device, a storage medium and a computer program product to at least solve the problem in the related art that the brake hydraulic compensation technology has slow response time, low execution accuracy and communication delay, which seriously affects the driving experience of the driver during the coasting energy recovery process of the vehicle.

[0006] According to one aspect of the embodiments of this application, a control method for a target vehicle is provided, comprising: determining, when it is determined that the target vehicle is in a coasting state, a maximum required negative torque of the target vehicle is determined according to the driving intention of the target vehicle, wherein the maximum required negative torque is used to provide braking force corresponding to a target deceleration to the target vehicle, the target deceleration being determined according to the driving intention; adjusting the motor negative torque output by the motor of the target vehicle according to the required negative torque of the target vehicle at different times; and, when it is determined that the difference between a first motor negative torque output by the motor at a first time and the maximum motor negative torque of the motor is less than a first threshold, sending a brake hydraulic start signal to a brake hydraulic controller at the first time, wherein the brake hydraulic start signal is used to indicate the start of brake hydraulic operation, the brake hydraulic operation being used to... The motor output negative torque is compensated, and the output hydraulic negative torque of the brake hydraulic fluid at different times is determined according to the hydraulic compensation torque requirement at different times. Within a first time period, the second motor negative torque output by the motor at different times is adjusted based on the actual hydraulic execution value of the hydraulic negative torque at different times, so as to control the absolute value of the difference between the executed negative torque and the required negative torque of the target vehicle at different times within the first time period to be less than a second threshold. The start time of the first time period is the first moment, and the executed negative torque of the target vehicle at the end time of the first time period is the maximum required negative torque. The actual hydraulic execution value is determined based on the actual hydraulic compensation torque of the target vehicle and the hydraulic compensation torque requirement. The executed negative torque is the sum of the actual hydraulic compensation torque and the second motor negative torque.

[0007] In an exemplary embodiment, before sending a brake hydraulic start signal to the brake hydraulic controller at the first moment, the method further includes: if it is determined that the maximum motor negative torque is less than the maximum required negative torque, sending a pre-build pressure signal to the brake hydraulic controller at a second moment to eliminate the hydraulic clearance of the target vehicle, wherein the pre-build pressure signal is used to instruct the brake hydraulic controller to pre-build brake hydraulic pressure, the pre-build pressure target of the pre-build brake hydraulic pressure is calibrated according to the idle travel size of the target vehicle, and the second moment is earlier than the first moment.

[0008] In an exemplary embodiment, adjusting the second motor negative torque output by the motor at different times based on the actual hydraulic execution value of the hydraulic negative torque at different times within a first time period includes: determining the first actual hydraulic execution value of the hydraulic negative torque at a third time, wherein the first time period includes the third time; determining the first required negative torque of the target vehicle at the third time; and adjusting the third motor negative torque output by the motor at a fourth time based on the difference between the first required negative torque and the first actual hydraulic execution value, wherein the fourth time is the time following the third time.

[0009] In an exemplary embodiment, determining the first hydraulic actual execution value of the hydraulic negative torque at a third moment includes: calculating the first hydraulic compensation torque requirement of the target vehicle at the third moment through the vehicle torque controller, and sending the first hydraulic compensation torque requirement to the brake hydraulic controller; determining the first hydraulic actual compensation torque output by the brake hydraulic controller at the third moment; and determining the average value of the first hydraulic compensation torque requirement and the first hydraulic actual compensation torque as the first hydraulic actual execution value.

[0010] In an exemplary embodiment, calculating the first hydraulic compensation torque requirement of the target vehicle at the third moment using a vehicle torque controller includes: determining the maximum hydraulic compensation torque requirement of the target vehicle based on the maximum required torque and the maximum motor negative torque; fitting a curve of the change in hydraulic compensation torque requirement of the target vehicle at different moments using the vehicle torque controller, based on the maximum hydraulic compensation torque requirement and the first moment; and determining the first hydraulic compensation torque requirement of the target vehicle at the third moment based on the change curve.

[0011] In an exemplary embodiment, the method further includes: measuring the empty travel size of the target vehicle; establishing a hydraulic compensation model based on the braking system parameters of the target vehicle, wherein the braking system parameters include: the response time of the hydraulic pump, the delay of the brake line, and the friction characteristics of the brake; and processing the empty travel size through the hydraulic compensation model to obtain the pre-built pressure target.

[0012] In an exemplary embodiment, after adjusting the second motor negative torque output by the motor at different times according to the actual hydraulic execution value of the hydraulic negative torque at different times during a first time period, so as to control the absolute value of the difference between the executed negative torque and the required negative torque of the target vehicle at different times during the first time period to be less than a second threshold, the method further includes: determining the second actual hydraulic compensation torque of the hydraulic negative torque at the end of the first time period, and determining the fifth motor negative torque output by the motor at the end of the first time period; controlling the hydraulic controller to output the second actual hydraulic compensation torque during a second time period, and controlling the motor to output the fifth motor negative torque during the second time period, so as to provide the target vehicle with braking force corresponding to the target deceleration, wherein the second time period is later than the first time period, and the end time of the second time period is the time when the target vehicle begins to accelerate.

[0013] According to another aspect of the embodiments of this application, a control device for a target vehicle is also provided, comprising: a determining module, configured to determine the maximum required negative torque of the target vehicle based on the driving intention of the target vehicle when it is determined that the target vehicle is in a coasting state, wherein the maximum required negative torque is used to provide braking force corresponding to a target deceleration to the target vehicle, and the target deceleration is determined according to the driving intention; a first adjusting module, configured to adjust the motor negative torque output by the motor of the target vehicle according to the required negative torque of the target vehicle at different times; and a sending module, configured to send a brake hydraulic start signal to a brake hydraulic controller at a first time when it is determined that the difference between the first motor negative torque output by the motor at a first time and the maximum motor negative torque of the motor is less than a first threshold, wherein the brake hydraulic start signal is used to indicate the start of brake hydraulic operation. The brake hydraulic pressure is used to compensate for the negative torque output by the motor. The negative torque output by the brake hydraulic pressure at different times is determined according to the hydraulic compensation torque requirement at different times. The second adjustment module is used to adjust the second motor negative torque output by the motor at different times according to the actual hydraulic execution value of the negative torque at different times within a first time period, so as to control the absolute value of the difference between the execution negative torque and the required negative torque of the target vehicle at different times within the first time period to be less than a second threshold. The start time of the first time period is the first time, the execution negative torque of the target vehicle at the end time of the first time period is the maximum required negative torque, the actual hydraulic execution value is determined according to the actual hydraulic compensation torque of the target vehicle and the hydraulic compensation torque requirement, and the execution negative torque is the sum of the actual hydraulic compensation torque and the second motor negative torque.

[0014] According to another aspect of the embodiments of this application, a computer-readable storage medium is also provided, wherein a computer program is stored in the computer program, and the computer program is configured to execute the above-mentioned data file analysis method or data file transmission method when running.

[0015] According to another aspect of the embodiments of this application, an electronic device is also provided, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the data file analysis method or the data file transmission method described above through the computer program.

[0016] According to another aspect of the embodiments of this application, a computer program product is also provided, including a computer program that, when executed by a processor, implements the steps of the methods described in various embodiments of this application.

[0017] In this embodiment, after determining that the target vehicle is in a coasting state, the maximum required negative torque of the target vehicle is determined according to the driving intention of the target vehicle. This maximum required negative torque is used to provide braking force corresponding to the target deceleration, thereby enabling the target vehicle to complete energy recovery in the coasting state. First, the motor negative torque output of the target vehicle's motor is adjusted according to the required negative torque of the target vehicle at different times. When it is determined that the difference between the first motor negative torque output by the motor and the maximum motor negative torque of the motor is less than a first threshold, i.e., the motor negative torque is about to reach its maximum value, a brake hydraulic start signal is sent to the brake hydraulic controller at the first moment to start meeting the required negative torque in advance through brake hydraulic pressure. During the first time period, the second motor negative torque output by the motor is adjusted according to the actual hydraulic pressure values ​​at different times, controlling... The target vehicle's output negative torque during the first time period conforms to the curve of the required negative torque. The target vehicle's output negative torque at the end of the first time period is the maximum required negative torque. The actual hydraulic torque is determined based on the actual hydraulic compensation torque and the required hydraulic compensation torque. The output negative torque is the sum of the actual hydraulic compensation torque and the negative torque of the second motor. Using the above scheme, in the coasting energy recovery project, the brake hydraulic pressure is requested in advance and compensated by the faster and more controllable motor torque to accurately achieve the deceleration establishment effect, thereby ensuring the consistency of the driving experience. This solves the problems of slow response time, low execution accuracy, and communication lag in related technologies, which seriously affect the driver's driving experience during the coasting energy recovery process. Attached Figure Description

[0018] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0019] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a torque diagram (a) of an optional coasting brake hydraulic compensation control according to an embodiment of this application;

[0021] Figure 2 This is a flowchart of an optional target vehicle control method according to an embodiment of this application;

[0022] Figure 3 This is a schematic diagram of an optional controller signal communication according to an embodiment of this application;

[0023] Figure 4 This is a schematic diagram of an optional hydraulic actual execution value prediction according to an embodiment of this application;

[0024] Figure 5 This is a schematic diagram (II) of the torque of an optional coasting brake hydraulic compensation control according to an embodiment of this application;

[0025] Figure 6 This is a structural block diagram of an optional control device for a target vehicle according to an embodiment of this application. Detailed Implementation

[0026] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the scope of protection of the present application.

[0027] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0028] In coasting energy recovery conditions where charging capacity is limited, brake hydraulic pressure is directly used to compensate for the deceleration demand that the electric motor cannot meet. In this method, the variation curves of various torques of the vehicle are as follows: Figure 1 As shown, Figure 1 The solid black line represents the total demand negative torque, the red line represents the total execution negative torque, the green line represents the motor negative torque, the dashed blue line represents the hydraulic request negative torque, and the solid blue line represents the hydraulic execution negative torque. Methods that rely solely on brake hydraulic compensation to meet deceleration demands that the motor cannot fulfill will be... Figure 1 The communication lag and hydraulic response lag in stage ①, and the low hydraulic execution accuracy in stage ②, result in the final execution of negative torque failing to follow the required negative torque well, thus making the driver's perception of the deceleration build-up process poor.

[0029] To address the technical problems existing in related technologies, this embodiment provides a method for controlling a target vehicle. Figure 2 This is a flowchart of an optional target vehicle control method according to an embodiment of this application, the process including the following steps S202-S208:

[0030] Step S202: When it is determined that the target vehicle is in a coasting state, the maximum required negative torque of the target vehicle is determined according to the driving intention of the target vehicle, wherein the maximum required negative torque is used to provide braking force corresponding to the target deceleration to the target vehicle, and the target deceleration is determined according to the driving intention.

[0031] Step S204: Adjust the motor negative torque output of the target vehicle's motor according to the negative torque required by the target vehicle at different times;

[0032] Step S206: If the difference between the first motor negative torque output by the motor at the first moment and the maximum motor negative torque of the motor is less than the first threshold, a brake hydraulic start signal is sent to the brake hydraulic controller at the first moment. The brake hydraulic start signal is used to indicate the start of brake hydraulic operation. The brake hydraulic is used to compensate for the motor negative torque output by the motor. The output hydraulic negative torque of the brake hydraulic at different moments is determined according to the hydraulic compensation torque requirement at different moments.

[0033] Step S208: During the first time period, adjust the second motor negative torque output by the motor at different times according to the actual hydraulic execution value of the hydraulic negative torque at different times, so as to control the absolute value of the difference between the execution negative torque and the required negative torque of the target vehicle at different times during the first time period to be less than a second threshold. Here, the start time of the first time period is the first time, the execution negative torque of the target vehicle at the end time of the first time period is the maximum required negative torque, the actual hydraulic execution value is determined according to the actual hydraulic compensation torque of the target vehicle and the hydraulic compensation torque requirement, and the execution negative torque is the sum of the actual hydraulic compensation torque and the second motor negative torque.

[0034] Through the above steps, after determining that the target vehicle is in a coasting state, the maximum required negative torque of the target vehicle is determined according to the driving intention of the target driver. This maximum required negative torque is used to provide braking force corresponding to the target deceleration, thereby enabling the target vehicle to complete energy recovery in the coasting state. First, the motor negative torque output of the target vehicle is adjusted according to the required negative torque of the target vehicle at different times. When it is determined that the difference between the first motor negative torque output and the maximum motor negative torque is less than a first threshold, that is, when the motor negative torque is about to reach its maximum value, a brake hydraulic start signal is sent to the brake hydraulic controller at the first moment to start meeting the required negative torque in advance through brake hydraulic pressure. During the first time period, the second motor negative torque output of the motor is adjusted according to the actual hydraulic pressure values ​​at different times to control... The execution negative torque output by the target vehicle during the first time period conforms to the change curve of the required negative torque. The execution negative torque of the target vehicle at the end of the first time period is the maximum required negative torque. The actual hydraulic execution value is determined based on the actual hydraulic compensation torque and the hydraulic compensation torque requirement. The execution negative torque is the sum of the actual hydraulic compensation torque and the negative torque of the second motor. By adopting the above scheme, in the coasting energy recovery project, the brake hydraulic pressure is applied for in advance and compensated by the faster and more controllable motor torque to accurately achieve the deceleration establishment effect, thereby ensuring the consistency of driving experience. This solves the problems of slow response time, low execution accuracy and communication lag in the brake hydraulic compensation technology, which seriously affect the driver's driving experience during the coasting energy recovery process.

[0035] In an exemplary embodiment, before sending a brake hydraulic start signal to the brake hydraulic controller at the first moment, the method further includes: if it is determined that the maximum motor negative torque is less than the maximum required negative torque, sending a pre-build pressure signal to the brake hydraulic controller at a second moment to eliminate the hydraulic clearance of the target vehicle, wherein the pre-build pressure signal is used to instruct the brake hydraulic controller to pre-build brake hydraulic pressure, the pre-build pressure target of the pre-build brake hydraulic pressure is calibrated according to the idle travel size of the target vehicle, and the second moment is earlier than the first moment.

[0036] After the vehicle begins to coast, the maximum braking capacity of the motor during coasting needs to be calculated based on the battery and motor capabilities, which is the maximum negative torque of the motor mentioned above. The maximum required negative torque is then determined based on the driver's deceleration intention. If the maximum negative torque of the motor cannot meet the maximum required negative torque, it means that the deceleration establishment process needs to be assisted by brake hydraulic pressure during this coasting process. In order to ensure that the deceleration establishment process can be completed smoothly, brake hydraulic pressure needs to be pre-established to eliminate the hydraulic clearance of the vehicle. The pre-established pressure target can be calibrated in advance based on the size of the vehicle's idle travel.

[0037] Optionally, adjusting the second motor negative torque output by the motor at different times based on the actual hydraulic execution value of the hydraulic negative torque at different times during the first time period includes: determining the first actual hydraulic execution value of the hydraulic negative torque at a third time, wherein the first time period includes the third time; determining the first required negative torque of the target vehicle at the third time; and adjusting the third motor negative torque output by the motor at a fourth time based on the difference between the first required negative torque and the first actual hydraulic execution value, wherein the fourth time is the time following the third time.

[0038] At each moment (i.e., the third moment), in order to accurately execute the total required negative torque, the motor torque needs to be compensated according to the actual hydraulic conditions to ensure that the deceleration shape can be accurately executed. Since there is lag in the execution of the brake hydraulic torque, it is necessary to estimate the first actual hydraulic execution value of the hydraulic negative torque at the current moment, and determine the first required negative torque at the third moment according to the pre-established required negative torque curve. Then, the difference between the first required negative torque and the first actual hydraulic execution value is determined, and then the compensation is completed by the motor negative torque with a faster response speed, so that the actual executed negative torque at different moments (i.e., the above-mentioned executed negative torque) can fit the required negative torque (that is, the absolute value of the difference between the executed negative torque and the required negative torque is less than the second threshold).

[0039] Further, determining the first hydraulic actual execution value of the hydraulic negative torque at the third moment includes: calculating the first hydraulic compensation torque requirement of the target vehicle at the third moment through the vehicle torque controller, and sending the first hydraulic compensation torque requirement to the brake hydraulic controller; determining the first hydraulic actual compensation torque output by the brake hydraulic controller at the third moment; and determining the average value of the first hydraulic compensation torque requirement and the first hydraulic actual compensation torque as the first hydraulic actual execution value.

[0040] The process of estimating the first hydraulic actual execution value of the hydraulic negative torque at the third moment includes: firstly, calculating the first hydraulic compensation torque requirement of the vehicle at the third moment through the vehicle torque controller, and sending the first hydraulic compensation torque requirement to the brake hydraulic controller; simultaneously, obtaining the first hydraulic actual compensation torque actually output by the brake hydraulic controller at the third moment. Since there is a delay in the process of the vehicle torque controller sending a signal to control the brake hydraulic controller, and in the process of the brake hydraulic controller issuing the hydraulic actual compensation torque and actually completing the hydraulic compensation, it is assumed that the communication time of the round trip is approximately equal. Therefore, the average value of the first hydraulic compensation torque requirement and the first hydraulic actual compensation torque at this time is closest to the hydraulic actual execution value. Therefore, the average value of the two is calculated and used as the first hydraulic actual execution value.

[0041] The following combination Figure 3 and Figure 4To further explain the above process, such as... Figure 3 As shown, the vehicle motor torque controller first calculates and issues a hydraulic compensation torque demand. Upon receiving this request, the brake hydraulic controller begins hydraulic operation and issues the actual hydraulic compensation torque. After the aforementioned third moment, to accurately execute the total required negative torque, the motor torque needs to be compensated based on the actual hydraulic conditions to ensure accurate deceleration and shape establishment. The entire communication link loop is: vehicle motor torque controller -> brake hydraulic controller -> vehicle motor torque controller.

[0042] Figure 4 The curves showing the change of torque during the above process are shown. Figure 4 The blue dashed line ① represents the hydraulic compensation torque requirement issued by the vehicle's motor torque controller. Figure 4 The blue dashed line ③ represents the actual hydraulic compensation torque returned by the brake hydraulic controller from the vehicle motor torque controller. Figure 4 The solid line ② represents the actual hydraulic execution value predicted by the above method. This reference signal significantly improves the accuracy. The motor torque only needs to refer to this predicted signal to compensate for the negative torque, and the expected deceleration curve can be accurately established.

[0043] Optionally, the first hydraulic compensation torque requirement of the target vehicle at the third moment is calculated by the vehicle torque controller, including: determining the maximum hydraulic compensation torque requirement of the target vehicle based on the maximum required torque and the maximum motor negative torque; fitting the change curve of the hydraulic compensation torque requirement of the target vehicle at different moments using the vehicle torque controller, based on the maximum hydraulic compensation torque requirement and the first moment; and determining the first hydraulic compensation torque requirement of the target vehicle at the third moment based on the change curve.

[0044] The process of calculating the hydraulic compensation torque requirement of a vehicle at different times includes: initially, after determining that the maximum motor negative torque cannot meet the maximum required torque, the maximum hydraulic compensation torque requirement can be estimated based on the difference between the two. The target vehicle will officially start hydraulic compensation at the first moment. Therefore, the vehicle torque controller fits a relatively smooth change curve based on the maximum hydraulic compensation torque requirement and the first moment. Then, the first hydraulic compensation torque requirement of the target vehicle at different times can be determined based on the change curve.

[0045] In an exemplary embodiment, the method further includes: measuring the empty travel size of the target vehicle; establishing a hydraulic compensation model based on the braking system parameters of the target vehicle, wherein the braking system parameters include: the response time of the hydraulic pump, the delay of the brake line, and the friction characteristics of the brake; and processing the empty travel size through the hydraulic compensation model to obtain the pre-built pressure target.

[0046] Optionally, embodiments of this application propose a calibration method for pre-built pressure targets, including the following steps:

[0047] Step 1: Measure the free travel: First, it is necessary to accurately measure the free travel of the vehicle's braking system. This typically involves calibrating the pedal travel sensor and determining the distance traveled from when the pedal is depressed until the braking system begins to apply pressure. This data can be obtained through repeated trials in a laboratory or specific testing facility using specialized testing equipment.

[0048] Step 2: Establish a hydraulic compensation model: Based on the characteristics of the braking system (i.e., the braking system parameters mentioned above), including the response time of the hydraulic pump, the delay of the brake lines, and the friction characteristics of the brake, establish a hydraulic compensation model. The model should be able to predict the time difference from the start of pre-pressure build-up to the actual generation of effective braking force under different free stroke lengths.

[0049] Step 3: Calibrate the pre-build pressure value: The goal of pre-build pressure is to eliminate free play in the braking system and ensure that the hydraulic system can respond immediately when additional braking force is needed. The pre-build pressure value needs to be determined through testing to ensure that hydraulic compensation is not triggered too early or too late, while also avoiding excessive hydraulic pressure that could lead to unnecessary energy consumption or wear on the braking system.

[0050] Step 4: Consider Environmental Factors: The calibration of the pre-pressure target should also consider the influence of environmental factors, such as temperature and humidity. These factors may affect the viscosity of the hydraulic oil and the friction characteristics of the brake, thus affecting the pre-pressure effect. During the calibration process, data under different environmental conditions should be collected to ensure that the pre-pressure works effectively under various conditions.

[0051] Step 5: Verification and Adjustment: Under actual driving conditions, test drive vehicles with different idle travel lengths to collect driving experience and braking performance data, verifying the rationality of the pre-build pressure target calibration. This may require multiple adjustments to the pre-build pressure value and timing until the optimal calibration scheme is found, ensuring the best possible consistency in driving experience under coasting energy recovery conditions with limited charging capacity.

[0052] Step 6: Software Algorithm Optimization: The calibration of the pre-set pressure target also involves the optimization of the software algorithm to ensure that the motor torque controller can accurately predict the response of the brake hydraulic controller and the settling time of the actual hydraulic compensation torque. This may require the development of a specialized prediction algorithm that takes into account factors such as communication latency and hydraulic response time to achieve more precise control.

[0053] By following the steps above, the pre-build pressure target can be calibrated based on the vehicle's free travel, ensuring that the brake hydraulic system can respond promptly during coasting braking and improving the consistency of the driving experience.

[0054] Based on the above steps, after adjusting the second motor negative torque output by the motor at different times according to the actual hydraulic execution value of the hydraulic negative torque at different times during the first time period, so as to control the absolute value of the difference between the executed negative torque and the required negative torque of the target vehicle at different times during the first time period to be less than a second threshold, the method further includes: determining the second actual hydraulic compensation torque of the hydraulic negative torque at the end of the first time period, and determining the fifth motor negative torque output by the motor at the end of the first time period; controlling the hydraulic controller to output the second actual hydraulic compensation torque during the second time period, and controlling the motor to output the fifth motor negative torque during the second time period, so as to provide the target vehicle with braking force corresponding to the target deceleration, wherein the second time period is later than the first time period, and the end time of the second time period is the time when the target vehicle begins to accelerate.

[0055] During the hydraulic setup phase (i.e., the first time period mentioned above), the adjustment of the execution negative torque to accurately follow the deceleration curve was completed. Then, the hydraulic setup completed phase (i.e., the second time period mentioned above) was entered. In this phase, it is necessary to control the hydraulic negative torque and the motor negative torque to remain stable and continuously output the second hydraulic actual compensation torque and the fifth motor negative torque to ensure stable deceleration of the vehicle until the vehicle starts to accelerate again, at which point the current coasting phase ends.

[0056] This application proposes a hydraulic compensation control method for coasting braking that accurately follows the deceleration curve. The following is a combination of... Figure 5 The control method is described in detail, and includes the following steps:

[0057] Step 5.1: Calculate the maximum coasting braking capacity of the motor based on the battery and motor capabilities, i.e. Figure 5 The charging capacity (equivalent to the maximum negative torque of the motor mentioned above);

[0058] Step 5.2: When the motor's coasting braking capability cannot meet the driver's original intention to decelerate, i.e. Figure 5 At moment ① (equivalent to the second moment mentioned above), the braking hydraulic pressure is pre-established to eliminate the hydraulic clearance. The pre-established pressure target is calibrated based on the vehicle's idle travel distance, while the actual hydraulic pressure is affected by communication and hydraulic response delays. Figure 5 At the midpoint ②, pressure actually began to build;

[0059] Step 5.3: The deceleration request is close to but has not yet exceeded the maximum coasting braking capacity of the motor. Figure 5At moment ③ (equivalent to the first moment mentioned above), the brake hydraulic pressure is requested to be executed in advance. The target of the brake hydraulic pressure is the portion of the driver's original intention that exceeds the maximum capacity of the motor's coasting braking.

[0060] Step 5.4, regardless of Figure 5 During the hydraulic build-up phase before time ④ (first time period) and the hydraulic build-up completion phase after time ④ (second time period), the total deceleration build-up shape is compensated by the motor's negative torque. This compensation is based on the communication delay needed to predict and obtain the actual braking hydraulic signal, ensuring the overall deceleration effect. Figure 5 The final red line represents the actual negative torque that can accurately follow the deceleration curve.

[0061] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods according to the above embodiments can be implemented by means of software plus necessary general-purpose hardware platforms. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) and includes several instructions to cause a terminal device (which may be a mobile phone, computer, server, or network device, etc.) to execute the methods of the various embodiments of this application.

[0062] This application also provides a control device for a target vehicle, such as... Figure 6 As shown, Figure 6 This is a structural block diagram of an optional target vehicle control device according to an embodiment of this application. The device includes:

[0063] The determining module 62 is used to determine the maximum required negative torque of the target vehicle based on the driving intention of the target vehicle when it is determined that the target vehicle is in a coasting state. The maximum required negative torque is used to provide braking force corresponding to the target deceleration to the target vehicle, and the target deceleration is determined according to the driving intention.

[0064] The first adjustment module 64 is used to adjust the motor negative torque output by the motor of the target vehicle according to the negative torque required by the target vehicle at different times.

[0065] The sending module 66 is used to send a brake hydraulic start signal to the brake hydraulic controller at the first moment when it is determined that the difference between the first motor negative torque output by the motor at the first moment and the maximum motor negative torque of the motor is less than a first threshold. The brake hydraulic start signal is used to indicate the start of brake hydraulic execution. The brake hydraulic is used to compensate for the motor negative torque output by the motor. The output hydraulic negative torque of the brake hydraulic at different moments is determined according to the hydraulic compensation torque requirement at different moments.

[0066] The second adjustment module 68 is used to adjust the second motor negative torque output by the motor at different times according to the actual hydraulic execution value of the hydraulic negative torque at different times during a first time period, so as to control the absolute value of the difference between the execution negative torque and the required negative torque of the target vehicle at different times during the first time period to be less than a second threshold. The start time of the first time period is the first time, the execution negative torque of the target vehicle at the end time of the first time period is the maximum required negative torque, the actual hydraulic execution value is determined according to the actual hydraulic compensation torque of the target vehicle and the hydraulic compensation torque requirement, and the execution negative torque is the sum of the actual hydraulic compensation torque and the second motor negative torque.

[0067] Using the aforementioned device, after determining that the target vehicle is in a coasting state, the maximum required negative torque of the target vehicle is determined according to the driving intention of the target driver. This maximum required negative torque is used to provide braking force corresponding to the target deceleration, thereby enabling the target vehicle to complete energy recovery while coasting. First, the motor negative torque output of the target vehicle is adjusted according to the required negative torque of the target vehicle at different times. When the difference between the first motor negative torque output and the maximum motor negative torque is determined to be less than a first threshold, i.e., the motor negative torque is about to reach its maximum value, a brake hydraulic start signal is sent to the brake hydraulic controller at the first moment to start meeting the required negative torque in advance using brake hydraulic pressure. During the first time period, the second motor negative torque output is adjusted according to the actual hydraulic pressure values ​​at different times, controlling... The execution negative torque output by the target vehicle during the first time period conforms to the change curve of the required negative torque. The execution negative torque of the target vehicle at the end of the first time period is the maximum required negative torque. The actual hydraulic execution value is determined based on the actual hydraulic compensation torque and the hydraulic compensation torque requirement. The execution negative torque is the sum of the actual hydraulic compensation torque and the negative torque of the second motor. By adopting the above scheme, in the coasting energy recovery project, the brake hydraulic pressure is applied for in advance and compensated by the faster and more controllable motor torque to accurately achieve the deceleration establishment effect, thereby ensuring the consistency of driving experience. This solves the problems of slow response time, low execution accuracy and communication lag in the brake hydraulic compensation technology, which seriously affect the driver's driving experience during the coasting energy recovery process.

[0068] In an exemplary embodiment, the sending module 66 is further configured to send a pre-build pressure signal to the brake hydraulic controller at a second time when it is determined that the maximum motor negative torque is less than the maximum required negative torque, in order to eliminate the hydraulic clearance of the target vehicle. The pre-build pressure signal is used to instruct the brake hydraulic controller to pre-build brake hydraulic pressure. The pre-build pressure target for pre-building brake hydraulic pressure is calibrated according to the idle travel size of the target vehicle. The second time is earlier than the first time.

[0069] In an exemplary embodiment, the second adjustment module 68 is further configured to determine the first hydraulic actual execution value of the hydraulic negative torque at a third time, wherein the first time period includes the third time; determine the first demand negative torque of the target vehicle at the third time; and adjust the third motor negative torque output by the motor at a fourth time according to the difference between the first demand negative torque and the first hydraulic actual execution value, wherein the fourth time is the time following the third time.

[0070] Furthermore, the aforementioned determining module 62 is also used to calculate the first hydraulic compensation torque requirement of the target vehicle at the third moment through the vehicle torque controller, and send the first hydraulic compensation torque requirement to the brake hydraulic controller; determine the first actual hydraulic compensation torque output by the brake hydraulic controller at the third moment; and determine the average value of the first hydraulic compensation torque requirement and the first actual hydraulic compensation torque as the first actual hydraulic execution value.

[0071] Optionally, the aforementioned determining module 62 is further configured to determine the maximum hydraulic compensation torque requirement of the target vehicle based on the maximum required torque and the maximum motor negative torque; to fit the change curve of the hydraulic compensation torque requirement of the target vehicle at different times using the vehicle torque controller based on the maximum hydraulic compensation torque requirement and the first time moment; and to determine the first hydraulic compensation torque requirement of the target vehicle at the third time moment based on the change curve.

[0072] In an exemplary embodiment, the determining module 62 is further configured to measure the empty travel size of the target vehicle; establish a hydraulic compensation model based on the braking system parameters of the target vehicle, wherein the braking system parameters include: the response time of the hydraulic pump, the delay of the brake line, and the friction characteristics of the brake; and process the empty travel size through the hydraulic compensation model to obtain the pre-built pressure target.

[0073] Optionally, the second adjustment module 68 is further configured to determine the second actual hydraulic compensation torque at the end of the first time period, and to determine the fifth motor negative torque output by the motor at the end of the first time period; control the hydraulic controller to output the second actual hydraulic compensation torque during the second time period, and control the motor to output the fifth motor negative torque during the second time period, so as to provide the target vehicle with braking force corresponding to the target deceleration, wherein the second time period is later than the first time period, and the end of the second time period is the moment when the target vehicle begins to accelerate.

[0074] Embodiments of this application also provide a storage medium including a stored program, wherein the program executes any of the methods described above when it is run.

[0075] Optionally, in this embodiment, the storage medium may be configured to store program code for performing the following steps:

[0076] S1, when it is determined that the target vehicle is in a coasting state, the maximum required negative torque of the target vehicle is determined according to the driving intention of the target vehicle, wherein the maximum required negative torque is used to provide the target vehicle with braking force corresponding to the target deceleration, and the target deceleration is determined according to the driving intention;

[0077] S2, adjust the motor negative torque output of the target vehicle's motor according to the negative torque required by the target vehicle at different times;

[0078] S3, when it is determined that the difference between the first motor negative torque output by the motor at the first moment and the maximum motor negative torque of the motor is less than the first threshold, a brake hydraulic start signal is sent to the brake hydraulic controller at the first moment, wherein the brake hydraulic start signal is used to indicate the start of brake hydraulic execution, the brake hydraulic is used to compensate for the motor negative torque output by the motor, and the output hydraulic negative torque of the brake hydraulic at different moments is determined according to the hydraulic compensation torque requirement at different moments.

[0079] S4, within a first time period, adjust the second motor negative torque output by the motor at different times according to the actual hydraulic execution value of the hydraulic negative torque at different times, so as to control the absolute value of the difference between the execution negative torque and the required negative torque of the target vehicle at different times within the first time period to be less than a second threshold. Here, the start time of the first time period is the first time, the execution negative torque of the target vehicle at the end time of the first time period is the maximum required negative torque, the actual hydraulic execution value is determined according to the actual hydraulic compensation torque of the target vehicle and the hydraulic compensation torque requirement, and the execution negative torque is the sum of the actual hydraulic compensation torque and the second motor negative torque.

[0080] Embodiments of this application also provide an electronic device including a memory and a processor, wherein the memory stores a computer program and the processor is configured to run the computer program to perform the steps in any of the above method embodiments.

[0081] Optionally, the electronic device may further include a transmission device and an input / output device, wherein the transmission device is connected to the processor and the input / output device is connected to the processor.

[0082] Optionally, in this embodiment, the processor can be configured to perform the following steps via a computer program:

[0083] S1, when it is determined that the target vehicle is in a coasting state, the maximum required negative torque of the target vehicle is determined according to the driving intention of the target vehicle, wherein the maximum required negative torque is used to provide the target vehicle with braking force corresponding to the target deceleration, and the target deceleration is determined according to the driving intention;

[0084] S2, adjust the motor negative torque output of the target vehicle's motor according to the negative torque required by the target vehicle at different times;

[0085] S3, when it is determined that the difference between the first motor negative torque output by the motor at the first moment and the maximum motor negative torque of the motor is less than the first threshold, a brake hydraulic start signal is sent to the brake hydraulic controller at the first moment, wherein the brake hydraulic start signal is used to indicate the start of brake hydraulic execution, the brake hydraulic is used to compensate for the motor negative torque output by the motor, and the output hydraulic negative torque of the brake hydraulic at different moments is determined according to the hydraulic compensation torque requirement at different moments.

[0086] S4, within a first time period, adjust the second motor negative torque output by the motor at different times according to the actual hydraulic execution value of the hydraulic negative torque at different times, so as to control the absolute value of the difference between the execution negative torque and the required negative torque of the target vehicle at different times within the first time period to be less than a second threshold. Here, the start time of the first time period is the first time, the execution negative torque of the target vehicle at the end time of the first time period is the maximum required negative torque, the actual hydraulic execution value is determined according to the actual hydraulic compensation torque of the target vehicle and the hydraulic compensation torque requirement, and the execution negative torque is the sum of the actual hydraulic compensation torque and the second motor negative torque.

[0087] Optionally, in this embodiment, the storage medium may include, but is not limited to, various media capable of storing program code, such as USB flash drives, read-only memory (ROM), random access memory (RAM), portable hard drives, magnetic disks, or optical disks.

[0088] Embodiments of this application also provide a computer program product, including a non-volatile computer-readable storage medium storing the computer program product, wherein the computer program, when executed by a processor, implements the steps of the methods described in various embodiments of this application.

[0089] Optionally, in this embodiment, the computer program described above can be configured to perform the following steps when executed by a processor:

[0090] S1, when it is determined that the target vehicle is in a coasting state, the maximum required negative torque of the target vehicle is determined according to the driving intention of the target vehicle, wherein the maximum required negative torque is used to provide the target vehicle with braking force corresponding to the target deceleration, and the target deceleration is determined according to the driving intention;

[0091] S2, adjust the motor negative torque output of the target vehicle's motor according to the negative torque required by the target vehicle at different times;

[0092] S3, when it is determined that the difference between the first motor negative torque output by the motor at the first moment and the maximum motor negative torque of the motor is less than the first threshold, a brake hydraulic start signal is sent to the brake hydraulic controller at the first moment, wherein the brake hydraulic start signal is used to indicate the start of brake hydraulic execution, the brake hydraulic is used to compensate for the motor negative torque output by the motor, and the output hydraulic negative torque of the brake hydraulic at different moments is determined according to the hydraulic compensation torque requirement at different moments.

[0093] S4, within a first time period, adjust the second motor negative torque output by the motor at different times according to the actual hydraulic execution value of the hydraulic negative torque at different times, so as to control the absolute value of the difference between the execution negative torque and the required negative torque of the target vehicle at different times within the first time period to be less than a second threshold. Here, the start time of the first time period is the first time, the execution negative torque of the target vehicle at the end time of the first time period is the maximum required negative torque, the actual hydraulic execution value is determined according to the actual hydraulic compensation torque of the target vehicle and the hydraulic compensation torque requirement, and the execution negative torque is the sum of the actual hydraulic compensation torque and the second motor negative torque.

[0094] Optionally, specific examples in this embodiment can refer to the examples described in the above embodiments and optional implementations, and will not be repeated here.

[0095] Obviously, those skilled in the art should understand that the modules or steps of this application described above can be implemented using general-purpose computing devices. They can be centralized on a single computing device or distributed across a network of multiple computing devices. Optionally, they can be implemented using computer-executable program code, thereby storing them in a storage device for execution by a computing device. In some cases, the steps shown or described can be performed in a different order than those presented here, or they can be fabricated as separate integrated circuit modules, or multiple modules or steps can be fabricated as a single integrated circuit module. Thus, this application is not limited to any particular combination of hardware and software.

[0096] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the principles of this application should be included within the protection scope of this application.

Claims

1. A method for controlling a target vehicle, characterized in that, include: When it is determined that the target vehicle is in a coasting state, the maximum required negative torque of the target vehicle is determined according to the driving intention of the target vehicle. The maximum required negative torque is used to provide braking force corresponding to the target deceleration to the target vehicle, and the target deceleration is determined according to the driving intention. Adjust the motor negative torque output of the target vehicle's motor according to the negative torque required by the target vehicle at different times; If the difference between the first negative torque output by the motor at the first moment and the maximum negative torque of the motor is less than a first threshold, a brake hydraulic start signal is sent to the brake hydraulic controller at the first moment. The brake hydraulic start signal is used to indicate the start of brake hydraulic operation. The brake hydraulic is used to compensate for the negative torque output by the motor. The output hydraulic negative torque of the brake hydraulic at different moments is determined according to the hydraulic compensation torque requirement at different moments. Within a first time period, the second motor negative torque output by the motor at different times is adjusted based on the actual hydraulic execution value of the hydraulic negative torque at different times, so as to control the absolute value of the difference between the execution negative torque and the required negative torque of the target vehicle at different times within the first time period to be less than a second threshold. Here, the start time of the first time period is the first time, the execution negative torque of the target vehicle at the end time of the first time period is the maximum required negative torque, the actual hydraulic execution value is determined based on the actual hydraulic compensation torque of the target vehicle and the hydraulic compensation torque requirement, and the execution negative torque is the sum of the actual hydraulic compensation torque and the second motor negative torque.

2. The control method for the target vehicle according to claim 1, characterized in that, Before sending the brake hydraulic start signal to the brake hydraulic controller at the first moment, the method further includes: If it is determined that the maximum motor negative torque is less than the maximum required negative torque, a pre-build pressure signal is sent to the brake hydraulic controller at a second time to eliminate the hydraulic clearance of the target vehicle. The pre-build pressure signal is used to instruct the brake hydraulic controller to pre-build brake hydraulic pressure. The pre-build pressure target for the pre-build brake hydraulic pressure is calibrated according to the idle travel size of the target vehicle. The second time is earlier than the first time.

3. The control method for the target vehicle according to claim 1, characterized in that, Adjusting the second motor negative torque output by the motor at different times based on the actual hydraulic actuation value of the hydraulic negative torque at different times during the first time period includes: Determine the first actual hydraulic actuation value of the hydraulic negative torque at a third time moment, wherein the first time period includes the third time moment; Determine the first required negative torque of the target vehicle at the third time point; The third motor negative torque output by the motor at the fourth moment is adjusted according to the difference between the first required negative torque and the first hydraulic actual execution value, wherein the fourth moment is the moment following the third moment.

4. The control method for the target vehicle according to claim 3, characterized in that, Determining the first actual hydraulic actuation value of the hydraulic negative torque at the third moment includes: The first hydraulic compensation torque requirement of the target vehicle at the third moment is calculated by the vehicle torque controller, and the first hydraulic compensation torque requirement is sent to the brake hydraulic controller. The first hydraulic actual compensation torque output by the brake hydraulic controller at the third moment is determined; the average value of the first hydraulic compensation torque requirement and the first hydraulic actual compensation torque is determined as the first hydraulic actual execution value.

5. The control method for the target vehicle according to claim 4, characterized in that, The first hydraulic compensation torque requirement of the target vehicle at the third moment is calculated using the vehicle torque controller, including: The maximum hydraulic compensation torque requirement of the target vehicle is determined based on the maximum required torque and the maximum motor negative torque. The vehicle torque controller fits the change curve of the hydraulic compensation torque demand of the target vehicle at different times based on the maximum hydraulic compensation torque demand and the first moment. The first hydraulic compensation torque requirement of the target vehicle at the third moment is determined based on the change curve.

6. The control method for the target vehicle according to claim 2, characterized in that, The method further includes: measuring the empty travel distance of the target vehicle; A hydraulic compensation model is established based on the braking system parameters of the target vehicle, wherein the braking system parameters include: the response time of the hydraulic pump, the delay of the brake line, and the friction characteristics of the brake. The pre-build pressure target is obtained by processing the idle stroke size using the hydraulic compensation model.

7. The control method for the target vehicle according to claim 1, characterized in that, Within a first time period, the method further includes adjusting the second motor negative torque output by the motor at different times based on the actual hydraulic execution value of the hydraulic negative torque at different times, so as to control the absolute value of the difference between the executed negative torque and the required negative torque of the target vehicle at different times within the first time period to be less than a second threshold. The second hydraulic actual compensation torque is determined at the end of the first time period, and the fifth motor negative torque is determined at the end of the first time period. During the second time period, the hydraulic controller is controlled to output the second hydraulic actual compensation torque, and the motor is controlled to output the fifth motor negative torque to provide the target vehicle with the braking force corresponding to the target deceleration. The second time period is later than the first time period, and the end time of the second time period is the time when the target vehicle begins to accelerate.

8. A control device for a target vehicle, characterized in that, include: The determination module is used to determine the maximum required negative torque of the target vehicle based on the driving intention of the target vehicle when it is determined that the target vehicle is in a coasting state. The maximum required negative torque is used to provide braking force corresponding to the target deceleration to the target vehicle, and the target deceleration is determined according to the driving intention. The first adjustment module is used to adjust the motor negative torque output by the motor of the target vehicle according to the negative torque required by the target vehicle at different times. The sending module is configured to send a brake hydraulic start signal to the brake hydraulic controller at the first moment when it is determined that the difference between the first motor negative torque output by the motor at the first moment and the maximum motor negative torque of the motor is less than a first threshold. The brake hydraulic start signal is used to indicate the start of brake hydraulic execution. The brake hydraulic is used to compensate for the motor negative torque output by the motor. The output hydraulic negative torque of the brake hydraulic at different moments is determined according to the hydraulic compensation torque requirement at different moments. The second adjustment module is used to adjust the second motor negative torque output by the motor at different times according to the actual hydraulic execution value of the hydraulic negative torque at different times during the first time period, so as to control the absolute value of the difference between the execution negative torque and the required negative torque of the target vehicle at different times during the first time period to be less than a second threshold. The start time of the first time period is the first time, the execution negative torque of the target vehicle at the end time of the first time period is the maximum required negative torque, the actual hydraulic execution value is determined according to the actual hydraulic compensation torque of the target vehicle and the hydraulic compensation torque requirement, and the execution negative torque is the sum of the actual hydraulic compensation torque and the second motor negative torque.

9. A computer-readable storage medium, characterized in that, The computer-readable storage medium includes a stored program, wherein the program, when executed, performs the method described in any one of claims 1 to 7.

10. A computer program product, comprising a computer program, characterized in that, When the computer program is executed by a processor, it implements the method of any one of claims 1 to 7.

Images