Vehicle creep control methods, devices, equipment and storage media

Abstract

This invention relates to the field of vehicle control technology and discloses a vehicle creep control method, device, equipment, and storage medium. The method includes: determining the theoretical idle speed of the engine when the current driving state of the target vehicle is creeping; determining the theoretical torque of the rear axle based on the theoretical idle speed; calculating the theoretical torque of the target motor based on the theoretical torque of the rear axle and the rear axle reduction ratio; and controlling the creep speed of the target vehicle within a preset range by offsetting the drive torque based on the theoretical motor torque using the target motor controller. By using the above method, when the current driving state of the target vehicle is determined to be creeping, the target torque of the rear axle is determined based on the theoretical idle speed, and then the theoretical torque of the motor is calculated based on the target torque of the rear axle. An open-loop control method is used to control the creep speed of the target vehicle, thereby effectively improving the rationality of controlling the creep of hybrid vehicles and thus improving the driving experience.

Description

Technical Field

[0001] This invention relates to the field of vehicle control technology, and in particular to vehicle crawl control methods, devices, equipment, and storage media. Background Technology

[0002] With increasingly severe environmental and energy problems worldwide, countries continue to introduce stricter regulations to limit emissions of carbon dioxide and various harmful gases. Hybrid powertrain systems, combining the advantages of engines and electric motors, have received widespread attention in recent years. However, hardware weaknesses still exist in hybrid vehicles. The creep speed of vehicles with torque converters varies with the engine's idle speed. Furthermore, in hybrid vehicles, due to more frequent engine starts and stops, as well as energy recovery, the engine coolant temperature is not easily maintained above 90°C. This leads to more frequent instances of higher engine idle speeds, which in turn result in higher pump wheel torque, further increasing the vehicle's creep speed. In some cases, creeping can even result in shifting into second gear, ultimately leading to extremely unreasonable control of the creep speed in hybrid vehicles and a poor driving experience.

[0003] The above content is only used to help understand the technical solution of the present invention and does not represent an admission that the above content is prior art. Summary of the Invention

[0004] The main objective of this invention is to provide a vehicle creep control method, device, equipment, and storage medium, aiming to solve the technical problem that the existing technology for controlling the creep of hybrid vehicles is unreasonable, resulting in a poor driving experience.

[0005] To achieve the above objectives, the present invention provides a vehicle creep control method, which includes the following steps:

[0006] When the target vehicle is currently in a crawling state, determine the theoretical idle speed of the engine;

[0007] The theoretical torque of the rear axle is determined based on the theoretical idle speed.

[0008] The theoretical torque of the target motor is calculated based on the theoretical torque of the rear axle and the reduction ratio of the rear axle.

[0009] The target motor controller cancels out the drive torque according to the theoretical torque of the motor, so as to control the creep speed of the target vehicle to be within a preset range.

[0010] Optionally, determining the theoretical idle speed of the engine when the target vehicle is currently in a creeping state includes:

[0011] When the target vehicle is in a crawling state, obtain the engine's current coolant temperature, ambient temperature, and altitude parameters.

[0012] The engine controller calculates the current idle speed of the engine based on the current water temperature, the ambient temperature, and the altitude.

[0013] The theoretical idle speed is calculated based on the current idle speed of the engine and the current oil temperature of the transmission.

[0014] Optionally, before acquiring the engine's current coolant temperature, ambient temperature, and altitude parameters when the target vehicle is currently in a crawling state, the method further includes:

[0015] Obtain the current gear of the transmission, the current opening of the brake pedal, and the current opening of the accelerator pedal;

[0016] The current driving state of the target vehicle is determined based on the current gear of the transmission, the current opening of the brake pedal, and the current opening of the accelerator pedal.

[0017] Determine whether the target vehicle is currently in a crawling state.

[0018] Optionally, determining the theoretical rear axle torque based on the theoretical idle speed includes:

[0019] Obtain pump impeller torque parameters, torque ratio parameters, speed ratio parameters, creep parameters, and the current speed of the target vehicle;

[0020] The theoretical torque of the front axle is calculated based on the theoretical idle speed, the pump wheel torque parameters, the torque ratio parameters, and the speed ratio parameters.

[0021] The total torque of the front and rear axles is calculated based on the theoretical torque of the front axle, the creep parameters, and the current speed of the target vehicle.

[0022] The theoretical torque of the rear axle is calculated based on the theoretical torque of the front axle, the total torque of the front and rear axles, and a preset torque distribution mixing coefficient.

[0023] Optionally, calculating the theoretical front axle torque based on the theoretical idle speed, the pump wheel torque parameters, the torque ratio parameters, and the speed ratio parameters includes:

[0024] The theoretical idle speed is sent to the engine controller so that the engine controller can control the engine according to the theoretical idle speed. After the control is completed, the actual idle speed of the engine is fed back.

[0025] The theoretical torque of the front axle is calculated based on the actual idle speed, the pump wheel torque parameters, the torque ratio parameters, and the speed ratio parameters.

[0026] Optionally, the step of controlling the creep speed of the target vehicle to be within a preset range by canceling the drive torque according to the theoretical torque of the motor through the target motor controller includes:

[0027] The theoretical torque of the motor is sent to the target motor controller so that the target motor controller can control the target motor according to the theoretical torque. After the control is completed, the actual torque of the target motor is acquired in real time, and the drive torque is offset according to the actual torque of the motor so as to control the creep speed of the target vehicle to be within a preset range.

[0028] Optionally, the step of sending the theoretical torque of the motor to the target motor controller, so that the target motor controller controls the target motor according to the theoretical torque, and after the control is completed, acquiring the actual torque of the target motor in real time, and performing drive torque cancellation according to the actual torque of the motor to control the creep speed of the target vehicle within a preset range, includes:

[0029] The theoretical torque of the motor is sent to the target motor controller so that the target motor controller can control the target motor according to the theoretical torque. After the control is completed, the actual torque of the target motor is acquired in real time, and the actual torque of the front axle is offset according to the actual torque of the motor. After the offset is completed, the creep speed of the target vehicle is controlled to be within a preset range.

[0030] Furthermore, to achieve the above objectives, the present invention also proposes a vehicle creep control device, the vehicle creep control device comprising:

[0031] The status determination module is used to determine the theoretical idle speed of the engine when the target vehicle is in a creeping state.

[0032] The determination module is used to determine the theoretical torque of the rear axle based on the theoretical idle speed;

[0033] The calculation module is used to calculate the theoretical torque of the target motor based on the theoretical torque of the rear axle and the rear axle reduction ratio.

[0034] The control module is used to control the creep speed of the target vehicle to be within a preset range by offsetting the drive torque according to the theoretical torque of the motor through the target motor controller.

[0035] Furthermore, to achieve the above objectives, the present invention also proposes a vehicle crawl control device, which includes: a memory, a processor, and a vehicle crawl control program stored in the memory and executable on the processor, wherein the vehicle crawl control program is configured to implement the vehicle crawl control method as described above.

[0036] In addition, to achieve the above objectives, the present invention also proposes a storage medium storing a vehicle crawl control program, which, when executed by a processor, implements the vehicle crawl control method as described above.

[0037] The vehicle creep control method proposed in this invention determines the theoretical idle speed of the engine when the target vehicle is in a creeping state; determines the theoretical torque of the rear axle based on the theoretical idle speed; calculates the theoretical torque of the target motor based on the theoretical rear axle torque and the rear axle reduction ratio; and uses the target motor controller to cancel the drive torque based on the theoretical motor torque to control the creeping speed of the target vehicle within a preset range. By using the above method, when the target vehicle's current driving state is determined to be creeping, the target torque of the rear axle is determined based on the theoretical idle speed, and then the theoretical torque of the motor is calculated based on the target torque of the rear axle. An open-loop control method is used to control the creeping speed of the target vehicle, thereby effectively improving the rationality of controlling the creeping of hybrid vehicles and thus enhancing the driving experience. Attached Figure Description

[0038] Figure 1 This is a schematic diagram of the structure of a vehicle crawl control device in the hardware operating environment involved in the embodiments of the present invention;

[0039] Figure 2 This is a flowchart illustrating the first embodiment of the vehicle creep control method of the present invention;

[0040] Figure 3 This is a schematic diagram of the target vehicle architecture according to an embodiment of the vehicle creep control method of the present invention;

[0041] Figure 4 This is a flowchart illustrating the second embodiment of the vehicle creep control method of the present invention;

[0042] Figure 5 This is a flowchart illustrating the third embodiment of the vehicle creep control method of the present invention;

[0043] Figure 6 This is a schematic diagram of torque distribution in an embodiment of the vehicle creep control method of the present invention;

[0044] Figure 7 This is a schematic diagram of the functional modules of the first embodiment of the vehicle crawl control device of the present invention.

[0045] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0046] It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the scope of the invention.

[0047] Reference Figure 1 , Figure 1 This is a schematic diagram of the vehicle crawl control device structure in the hardware operating environment involved in the embodiments of the present invention.

[0048] like Figure 1 As shown, the vehicle crawl control device may include: a processor 1001, such as a central processing unit (CPU), a communication bus 1002, a user interface 1003, a network interface 1004, and a memory 1005. The communication bus 1002 is used to enable communication between these components. The user interface 1003 may include a display screen or an input unit such as a keyboard; optionally, the user interface 1003 may also include a standard wired interface or a wireless interface. The network interface 1004 may optionally include a standard wired interface or a wireless interface (such as a Wireless-Fidelity (Wi-Fi) interface). The memory 1005 may be a high-speed random access memory (RAM) or a stable non-volatile memory (NVM), such as a disk drive. The memory 1005 may also optionally be a storage device independent of the aforementioned processor 1001.

[0049] Those skilled in the art will understand that Figure 1 The structure shown does not constitute a limitation on the vehicle crawl control device and may include more or fewer components than shown, or combine certain components, or have different component arrangements.

[0050] like Figure 1 As shown, the memory 1005, which serves as a storage medium, may include an operating system, a network communication module, a user interface module, and a vehicle crawl control program.

[0051] exist Figure 1In the vehicle crawl control device shown, the network interface 1004 is mainly used for data communication with the network integrated platform workstation; the user interface 1003 is mainly used for data interaction with the user; the processor 1001 and memory 1005 in the vehicle crawl control device of the present invention can be set in the vehicle crawl control device, and the vehicle crawl control device calls the vehicle crawl control program stored in the memory 1005 through the processor 1001 and executes the vehicle crawl control method provided in the embodiment of the present invention.

[0052] Based on the above hardware structure, an embodiment of the vehicle creep control method of the present invention is proposed.

[0053] Reference Figure 2 , Figure 2 This is a flowchart illustrating the first embodiment of the vehicle creep control method of the present invention.

[0054] In the first embodiment, the vehicle creep control method includes the following steps:

[0055] Step S10: When the target vehicle is currently in a crawling state, determine the theoretical idle speed of the engine.

[0056] It should be noted that the execution subject in this embodiment is a vehicle crawl control device, but it can also be other devices that can achieve the same or similar functions, such as a vehicle controller. This embodiment does not limit this, and in this embodiment, a vehicle controller is used as an example for explanation.

[0057] It should be understood that the vehicle model for creep control in this embodiment can be a P1P4 hybrid architecture vehicle with a 6AT transmission and a torque converter, as shown in the reference. Figure 3 The diagram shows the architecture of the P1P4 hybrid vehicle, which includes a high-voltage battery management system (HV Battery), dual inverters, a transmission, a P1f motor, and a P4 motor. The target vehicle is traveling in the left direction, and the P4 motor is located on the rear axle.

[0058] It is understandable that the theoretical idle speed refers to the idle speed calculated by the vehicle controller and used to control the engine. The specific condition for determining the theoretical idle speed of the engine is that the target vehicle is in a hybrid parallel state and the current driving state is a creeping state.

[0059] Step S20: Determine the theoretical torque of the rear axle based on the theoretical idle speed.

[0060] It is understandable that the theoretical torque of the rear axle refers to the theoretical torque of the rear axle of the target vehicle. This theoretical torque of the rear axle is calculated by the vehicle controller based on the total torque of the front and rear axles of the target vehicle and the theoretical torque of the front axle.

[0061] Step S30: Calculate the theoretical torque of the target motor based on the theoretical torque of the rear axle and the reduction ratio of the rear axle.

[0062] It should be understood that the theoretical torque of the motor refers to the theoretical torque used to control the target motor to operate. The target motor can be a P4 motor. The theoretical torque of the motor is calculated based on the theoretical torque of the rear axle and the rear axle reduction ratio. The rear axle reduction ratio refers to the ratio by which the reducer reduces the speed on the drive shaft. This reducer is installed on the rear axle of the target vehicle.

[0063] In step S40, the target motor controller cancels the drive torque according to the theoretical torque of the motor to control the creep speed of the target vehicle to be within a preset range.

[0064] It is understandable that the preset range refers to the speed range within which the vehicle meets the crawling requirements. This preset range can be 7-8 km / h. Specifically, the target motor controller cancels the drive torque according to the theoretical torque of the motor. At this time, the canceled torque can just control the crawling speed of the target vehicle to be within the preset range.

[0065] Furthermore, in order to effectively improve the accuracy of controlling the creeping vehicle of the target vehicle, step S40 includes: sending the theoretical torque of the motor to the target motor controller so that the target motor controller controls the target motor according to the theoretical torque of the motor; after the control is completed, acquiring the actual torque of the target motor in real time, and offsetting the drive torque according to the actual torque of the motor to control the creeping speed of the target vehicle to be within a preset range.

[0066] It should be understood that the target motor controller refers to the controller that controls the P4 motor. After the vehicle controller calculates the theoretical torque of the target motor, it sends the theoretical torque to the target motor controller. After receiving the theoretical torque, the target motor controller controls the target motor according to the theoretical torque. After the control is completed, it obtains the actual torque of the target motor in real time, and then uses the actual torque to cancel the drive torque. At this time, the creep speed of the target vehicle can be controlled within the preset range.

[0067] Furthermore, to effectively improve the accuracy of controlling the creeping speed of the target vehicle, the step of sending the theoretical torque of the motor to the target motor controller, so that the target motor controller controls the target motor according to the theoretical torque, and after the control is completed, acquiring the actual torque of the target motor in real time, and performing drive torque cancellation according to the actual torque of the motor to control the creeping speed of the target vehicle within a preset range, includes: sending the theoretical torque of the motor to the target motor controller, so that the target motor controller controls the target motor according to the theoretical torque, acquiring the actual torque of the target motor in real time after the control is completed, performing drive torque cancellation according to the actual torque of the motor to control the creeping speed of the target vehicle within a preset range.

[0068] Understandably, extensive experimental data shows that at an engine speed of 1250 rpm, the creep speed can reach 14.9 kph, while simultaneously shifting from 1st to 2nd gear. This completely contradicts the definition of a vehicle's creep function. Furthermore, in hybrid vehicles, the number of engine start-stop cycles is significantly increased, causing the engine coolant temperature to be unable to maintain its optimal operating temperature for extended periods. Consequently, the engine idle speed under creep conditions often fluctuates between 1000 rpm and 1500 rpm, resulting in significant variations in the maximum creep speed. Therefore, it is necessary to generate negative torque from the rear axle via the P4 motor to offset some of the torque from the front axle. Specifically, an open-loop control method is used to offset the actual torque from the front axle based on the actual torque of the motor, thereby controlling the target vehicle's creep speed within a preset range to achieve balance.

[0069] This embodiment determines the theoretical idle speed of the engine when the target vehicle is in a creeping state; determines the theoretical torque of the rear axle based on the theoretical idle speed; calculates the theoretical torque of the target motor based on the theoretical torque of the rear axle and the rear axle reduction ratio; and uses the target motor controller to cancel the drive torque based on the theoretical motor torque to control the creeping speed of the target vehicle within a preset range. By using this method, when the target vehicle is determined to be in a creeping state, the target torque of the rear axle is determined based on the theoretical idle speed, and then the theoretical torque of the motor is calculated based on the target torque of the rear axle. An open-loop control method is used to control the creeping speed of the target vehicle, thereby effectively improving the rationality of controlling the creeping of hybrid vehicles and thus enhancing the driving experience.

[0070] In one embodiment, such as Figure 4 The second embodiment of the vehicle creep control method of the present invention, based on the first embodiment, includes step S10, which includes:

[0071] Step S101: When the target vehicle is in a crawling state, obtain the engine's current coolant temperature, ambient temperature, and altitude parameters.

[0072] It should be understood that the current water temperature refers to the engine's water temperature at the current moment, the ambient temperature refers to the ambient temperature at the engine's location, and the altitude parameter refers to the altitude parameter at the engine's location, which includes, but is not limited to, altitude. When the target vehicle's current driving state is determined to be crawling, the current water temperature, ambient temperature, and altitude parameter are obtained.

[0073] Furthermore, in order to effectively improve the accuracy of determining the current driving state of the target vehicle, before step S101, the method further includes: obtaining the current gear of the transmission, the current opening of the brake pedal, and the current opening of the accelerator pedal; determining the current driving state of the target vehicle based on the current gear of the transmission, the current opening of the brake pedal, and the current opening of the accelerator pedal; and determining whether the current driving state of the target vehicle is a crawling state.

[0074] Understandably, the current gear refers to the gear of the transmission at the current moment, such as P, R, N, and D. The current pedal opening refers to the opening of the brake pedal and accelerator pedal at the current moment. The larger the current pedal opening, the deeper the brake pedal and accelerator pedal are pressed. Then, based on the current gear of the transmission, the current opening of the brake pedal, and the current opening of the accelerator pedal, the current driving state of the target vehicle is determined, and then it is determined whether the current driving state is a crawling state.

[0075] Step S102: The engine controller calculates the current idle speed of the engine based on the current water temperature, the ambient temperature, and the altitude.

[0076] It is understandable that the current idle speed refers to the engine's idle speed under the current coolant temperature, ambient temperature, and altitude parameters. The current idle speed is calculated based on the current coolant temperature, ambient temperature, and altitude parameters of the engine.

[0077] Step S103: Calculate the theoretical idle speed based on the current idle speed of the engine and the current oil temperature of the transmission.

[0078] It should be understood that the current oil temperature refers to the temperature of the transmission fluid. The transmission can be a 6-speed automatic transmission with a torque converter. After obtaining the current idle speed of the engine, the theoretical idle speed is calculated based on the current idle speed and the current oil temperature.

[0079] This embodiment obtains the engine's current coolant temperature, ambient temperature, and altitude parameters when the target vehicle is in a crawling state. The engine controller calculates the current idle speed of the engine based on these parameters. The theoretical idle speed is then calculated based on the current idle speed and the current transmission oil temperature. By using this method, when the target vehicle is determined to be in a crawling state, the engine controller calculates the current idle speed based on the engine's current coolant temperature, ambient temperature, and altitude parameters, and then calculates the theoretical idle speed based on the current idle speed and the current transmission oil temperature, thereby effectively improving the accuracy of calculating the theoretical idle speed.

[0080] In one embodiment, such as Figure 5 The third embodiment of the vehicle creep control method of the present invention, based on the first embodiment, includes step S20, which includes:

[0081] Step S201: Obtain pump wheel torque parameters, torque ratio parameters, speed ratio parameters, creep parameters, and the current speed of the target vehicle.

[0082] It is understandable that torque ratio parameters refer to the torque ratio-related parameters of the hydraulic torque converter, pump wheel torque parameters refer to the relevant parameters of the pump wheel torque model, such as the mapping relationship between engine speed and pump wheel torque, speed ratio parameters include the gearbox gear ratio and the front axle final drive ratio, and current vehicle speed refers to the speed of the target vehicle at the current moment.

[0083] Step S202: Calculate the theoretical torque of the front axle based on the theoretical idle speed, the pump wheel torque parameters, the torque ratio parameters, and the speed ratio parameters.

[0084] It should be understood that the theoretical torque of the front axle refers to the theoretical torque of the front axle of the target vehicle. This theoretical torque is calculated based on the theoretical idle speed, pump wheel torque parameters, torque ratio parameters, and speed ratio parameters.

[0085] Furthermore, in order to effectively improve the accuracy of calculating the theoretical torque of the front axle, step S202 includes: sending the theoretical idle speed to the engine controller so that the engine controller controls the engine according to the theoretical idle speed; after the control is completed, feeding back the actual idle speed of the engine; and calculating the theoretical torque of the front axle according to the actual idle speed, the pump wheel torque parameter, the torque ratio parameter, and the speed ratio parameter.

[0086] Understandably, after obtaining the theoretical idle speed, the vehicle controller sends it to the engine controller. The engine controller then controls the engine based on the received theoretical idle speed. After control is complete, it acquires the actual idle speed and feeds it back to the vehicle controller. The vehicle controller then calculates the theoretical front axle torque based on the actual idle speed, pump impeller torque parameters, torque ratio parameters, and speed ratio parameters. Specifically:

[0087] T F =T imp ·i T ·i gn ·i FD ;

[0088] Among them, T F T is the theoretical torque of the front axle. imp For pump impeller torque parameters, i T i is the torque ratio parameter. gn For gearbox gear ratios, i FD This is the front axle final drive ratio.

[0089] Step S203: Calculate the total torque of the front and rear axles based on the theoretical torque of the front axle, the creep parameters, and the current speed of the target vehicle.

[0090] Understandably, the creep parameters include the creep target speed and the creep control coefficient. After obtaining the theoretical torque of the front axle, the total torque of the front and rear axles is calculated based on the theoretical torque of the front axle, the creep target speed, the creep control coefficient, and the current speed of the target vehicle.

[0091] Step S204: Calculate the theoretical torque of the rear axle based on the theoretical torque of the front axle, the total torque of the front and rear axles, and the preset torque distribution mixing coefficient.

[0092] It should be understood that the preset torque distribution mixing coefficient refers to the coefficient of the theoretical torque of the axle after distribution. The value range of this preset torque distribution mixing coefficient is (0,1). Figure 6 The torque distribution diagram is as follows: ToFrontTarget is the theoretical torque of the front axle, ToSum is the total torque of the front and rear axles, ToRear is the theoretical torque of the rear axle, and Blending Factor is the preset torque distribution mixing coefficient. After obtaining the theoretical torque of the front axle ToFrontTarget and the total torque of the front and rear axles ToSum, the preset torque distribution mixing coefficient Blending Factor is used to make the total torque of the front and rear axles ToSum less than the theoretical torque of the front axle ToFrontTarget. Then, the theoretical torque of the rear axle in the opposite direction is distributed through the total torque of the front and rear axles ToSum.

[0093] This embodiment obtains pump impeller torque parameters, torque ratio parameters, speed ratio parameters, creep parameters, and the current speed of the target vehicle; calculates the theoretical torque of the front axle based on the theoretical idle speed, pump impeller torque parameters, torque ratio parameters, and speed ratio parameters; calculates the total torque of the front and rear axles based on the theoretical torque of the front axle, the creep parameters, and the current speed of the target vehicle; and calculates the theoretical torque of the rear axle based on the theoretical torque of the front axle, the total torque of the front and rear axles, and a preset torque distribution mixing coefficient. By using the above method, the theoretical torque of the front axle is calculated based on the theoretical idle speed, pump impeller torque parameters, torque ratio parameters, and speed ratio parameters. Then, the total torque of the front and rear axles is calculated based on the theoretical torque of the front axle, the creep parameters, and the current speed of the target vehicle. Finally, the preset torque distribution mixing coefficient is used to calculate the total torque of the front and rear axles based on the theoretical torque of the front axle and the total torque of the front and rear axles, thereby effectively improving the accuracy of calculating the total torque of the front and rear axles.

[0094] Furthermore, this embodiment of the invention also proposes a storage medium storing a vehicle crawl control program, which, when executed by a processor, implements the steps of the vehicle crawl control method described above.

[0095] Since this storage medium adopts all the technical solutions of all the above embodiments, it has at least all the beneficial effects brought about by the technical solutions of the above embodiments, which will not be repeated here.

[0096] In addition, refer to Figure 7 The present invention also proposes a vehicle creep control device, the vehicle creep control device comprising:

[0097] The state determination module 10 is used to determine the theoretical idle speed of the engine when the current driving state of the target vehicle is creeping.

[0098] The determination module 20 is used to determine the theoretical torque of the rear axle based on the theoretical idle speed.

[0099] The calculation module 30 is used to calculate the theoretical torque of the target motor based on the theoretical torque of the rear axle and the reduction ratio of the rear axle.

[0100] The control module 40 is used to control the creep speed of the target vehicle to be within a preset range by offsetting the drive torque according to the theoretical torque of the motor through the target motor controller.

[0101] This embodiment determines the theoretical idle speed of the engine when the target vehicle is in a creeping state; determines the theoretical torque of the rear axle based on the theoretical idle speed; calculates the theoretical torque of the target motor based on the theoretical torque of the rear axle and the rear axle reduction ratio; and uses the target motor controller to cancel the drive torque based on the theoretical motor torque to control the creeping speed of the target vehicle within a preset range. By using this method, when the target vehicle is determined to be in a creeping state, the target torque of the rear axle is determined based on the theoretical idle speed, and then the theoretical torque of the motor is calculated based on the target torque of the rear axle. An open-loop control method is used to control the creeping speed of the target vehicle, thereby effectively improving the rationality of controlling the creeping of hybrid vehicles and thus enhancing the driving experience.

[0102] It should be noted that the workflow described above is merely illustrative and does not limit the scope of protection of this invention. In practical applications, those skilled in the art can select some or all of the workflow to achieve the purpose of this embodiment according to actual needs, and no restrictions are imposed here.

[0103] In addition, for technical details not described in detail in this embodiment, please refer to the vehicle crawl control method provided in any embodiment of the present invention, which will not be repeated here.

[0104] In one embodiment, the state determination module 10 is further configured to, when the current driving state of the target vehicle is creeping, acquire the current coolant temperature of the engine, the ambient temperature, and the altitude parameters; calculate the current idle speed of the engine by the engine controller based on the current coolant temperature, the ambient temperature, and the altitude parameters; and calculate the theoretical idle speed based on the current idle speed of the engine and the current oil temperature of the transmission.

[0105] In one embodiment, the state determination module 10 is further configured to acquire the current gear of the transmission, the current opening of the brake pedal, and the current opening of the accelerator pedal; determine the current driving state of the target vehicle based on the current gear of the transmission, the current opening of the brake pedal, and the current opening of the accelerator pedal; and determine whether the current driving state of the target vehicle is a crawling state.

[0106] In one embodiment, the determining module 20 is further configured to acquire pump wheel torque parameters, torque ratio parameters, speed ratio parameters, creep parameters, and the current speed of the target vehicle; calculate the theoretical torque of the front axle based on the theoretical idle speed, the pump wheel torque parameters, the torque ratio parameters, and the speed ratio parameters; calculate the total torque of the front and rear axles based on the theoretical torque of the front axle, the creep parameters, and the current speed of the target vehicle; and calculate the theoretical torque of the rear axle based on the theoretical torque of the front axle, the total torque of the front and rear axles, and a preset torque distribution mixing coefficient.

[0107] In one embodiment, the determining module 20 is further configured to send the theoretical idle speed to the engine controller, so that the engine controller controls the engine according to the theoretical idle speed, and after the control is completed, feed back the actual idle speed of the engine; and calculate the theoretical front axle torque according to the actual idle speed, the pump wheel torque parameter, the torque ratio parameter and the speed ratio parameter.

[0108] In one embodiment, the control module 40 is further configured to send the theoretical torque of the motor to the target motor controller, so that the target motor controller controls the target motor according to the theoretical torque of the motor. After the control is completed, the actual torque of the target motor is obtained in real time, and the drive torque is offset according to the actual torque of the motor, so as to control the creep speed of the target vehicle to be within a preset range.

[0109] In one embodiment, the control module 40 is further configured to send the theoretical torque of the motor to the target motor controller, so that the target motor controller controls the target motor according to the theoretical torque of the motor. After the control is completed, the actual torque of the target motor is obtained in real time, and the actual torque of the front axle is offset according to the actual torque of the motor. After the offset is completed, the creep speed of the target vehicle is controlled to be within a preset range.

[0110] Other embodiments or implementation methods of the vehicle crawl control device described in this invention can be found in the above-described method embodiments, and will not be repeated here.

[0111] Furthermore, it should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or system that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or system. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or system that includes that element.

[0112] The sequence numbers of the above embodiments of the present invention are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0113] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods of 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 the present invention, 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 read-only memory (ROM) / RAM, magnetic disk, optical disk) and includes several instructions to cause a terminal device (which may be a mobile phone, computer, all-in-one platform workstation, or network device, etc.) to execute the methods described in the various embodiments of the present invention.

[0114] The above are merely preferred embodiments of the present invention and do not limit the scope of the patent. Any equivalent structural or procedural transformations made based on the description and drawings of the present invention, or direct or indirect applications in other related technical fields, are similarly included within the scope of patent protection of the present invention.

Claims

1. A vehicle creep control method, characterized in that, The vehicle creep control method includes the following steps: When the target vehicle is currently in a crawling state, determine the theoretical idle speed of the engine; The theoretical torque of the rear axle is determined based on the theoretical idle speed. The theoretical torque of the target motor is calculated based on the theoretical torque of the rear axle and the reduction ratio of the rear axle. The target motor controller cancels out the drive torque according to the theoretical torque of the motor, so as to control the creep speed of the target vehicle to be within a preset range; The determination of the theoretical rear axle torque based on the theoretical idle speed includes: Obtain pump impeller torque parameters, torque ratio parameters, speed ratio parameters, creep parameters, and the current speed of the target vehicle; The theoretical torque of the front axle is calculated based on the theoretical idle speed, the pump wheel torque parameters, the torque ratio parameters, and the speed ratio parameters. The total torque of the front and rear axles is calculated based on the theoretical torque of the front axle, the creep parameters, and the current speed of the target vehicle. The theoretical torque of the rear axle is calculated based on the theoretical torque of the front axle, the total torque of the front and rear axles, and a preset torque distribution mixing coefficient. The step of controlling the creep speed of the target vehicle within a preset range by canceling the drive torque according to the theoretical torque of the motor through the target motor controller includes: The theoretical torque of the motor is sent to the target motor controller so that the target motor controller can control the target motor according to the theoretical torque. After the control is completed, the actual torque of the target motor is acquired in real time, and the actual torque of the front axle is offset according to the actual torque of the motor. After the offset is completed, the creep speed of the target vehicle is controlled to be within a preset range.

2. The vehicle creep control method as described in claim 1, characterized in that, Determining the theoretical idle speed of the engine when the target vehicle is currently in a creeping state includes: When the target vehicle is in a crawling state, obtain the engine's current coolant temperature, ambient temperature, and altitude parameters. The engine controller calculates the current idle speed of the engine based on the current water temperature, the ambient temperature, and the altitude. The theoretical idle speed is calculated based on the current idle speed of the engine and the current oil temperature of the transmission.

3. The vehicle creep control method as described in claim 2, characterized in that, Before acquiring the engine's current coolant temperature, ambient temperature, and altitude parameters when the target vehicle is currently in a crawling state, the process also includes: Obtain the current gear of the transmission, the current opening of the brake pedal, and the current opening of the accelerator pedal; The current driving state of the target vehicle is determined based on the current gear of the transmission, the current opening of the brake pedal, and the current opening of the accelerator pedal. Determine whether the target vehicle is currently in a crawling state.

4. The vehicle creep control method as described in claim 1, characterized in that, The calculation of the theoretical front axle torque based on the theoretical idle speed, the pump wheel torque parameters, the torque ratio parameters, and the speed ratio parameters includes: The theoretical idle speed is sent to the engine controller so that the engine controller can control the engine according to the theoretical idle speed. After the control is completed, the actual idle speed of the engine is fed back. The theoretical torque of the front axle is calculated based on the actual idle speed, the pump wheel torque parameters, the torque ratio parameters, and the speed ratio parameters.

5. A vehicle creep control device, characterized in that, The vehicle crawl control device includes: The status determination module is used to determine the theoretical idle speed of the engine when the target vehicle is in a creeping state. The determination module is used to determine the theoretical torque of the rear axle based on the theoretical idle speed; The calculation module is used to calculate the theoretical torque of the target motor based on the theoretical torque of the rear axle and the rear axle reduction ratio. The control module is used to control the creep speed of the target vehicle to be within a preset range by canceling the drive torque according to the theoretical torque of the motor through the target motor controller. The calculation module is also used to acquire pump wheel torque parameters, torque ratio parameters, speed ratio parameters, creep parameters, and the current speed of the target vehicle; calculate the theoretical torque of the front axle based on the theoretical idle speed, the pump wheel torque parameters, the torque ratio parameters, and the speed ratio parameters; calculate the total torque of the front and rear axles based on the theoretical torque of the front axle, the creep parameters, and the current speed of the target vehicle; and calculate the theoretical torque of the rear axle based on the theoretical torque of the front axle, the total torque of the front and rear axles, and a preset torque distribution mixing coefficient. The step of controlling the creep speed of the target vehicle within a preset range by canceling the drive torque according to the theoretical torque of the motor through the target motor controller includes: The theoretical torque of the motor is sent to the target motor controller so that the target motor controller can control the target motor according to the theoretical torque. After the control is completed, the actual torque of the target motor is acquired in real time, and the actual torque of the front axle is offset according to the actual torque of the motor. After the offset is completed, the creep speed of the target vehicle is controlled to be within a preset range.

6. A vehicle creep control device, characterized in that, The vehicle crawl control device includes: a memory, a processor, and a vehicle crawl control program stored in the memory and executable on the processor, wherein the vehicle crawl control program is configured to implement the vehicle crawl control method as described in any one of claims 1 to 4.

7. A storage medium, characterized in that, The storage medium stores a vehicle crawl control program, which, when executed by a processor, implements the vehicle crawl control method as described in any one of claims 1 to 4.

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