A vehicle speed regulation control method, device, storage medium and vehicle

Abstract

The application provides a vehicle speed regulation control method and device, a storage medium and a vehicle, and belongs to the technical field of vehicles. In the case where the vehicle is in a slipping working condition, the target output shaft speed of a transmission output shaft and the target motor speed of a motor are determined. In the case where the working state of a hydraulic torque converter locking mechanism is an open state, the target hydraulic value of a transmission clutch is determined based on the target output shaft speed and the current output shaft speed of the transmission output shaft. Then, the transmission clutch is controlled to perform a speed regulation operation on the transmission output shaft based on the target hydraulic value. Meanwhile, the motor is controlled to perform a speed regulation operation based on the target motor speed and the current motor speed. In the case where the vehicle is in a slipping working condition, the application can realize fast and accurate speed control of the transmission and the motor, thereby effectively improving the anti-slip effect of the vehicle.

Description

Technical Field

[0001] This application relates to the field of vehicle technology, and in particular to a vehicle speed control method, device, storage medium, and vehicle. Background Technology

[0002] For new energy vehicles equipped with hydraulic torque converters, the motor and transmission rely on the hydraulic torque converter to transmit torque and speed. When the hydraulic torque converter lock-up mechanism is in the closed state, the motor and transmission are in a hard connection state; when the hydraulic torque converter lock-up mechanism is in the open state, the motor and transmission are in a soft connection state, and the hydraulic torque converter transmits power through hydraulic force.

[0003] When accelerating from a standstill with heavy throttle or driving on surfaces with low traction, vehicle slippage often occurs, triggering the anti-slip function. This function reduces the torque output of the power source to prevent wheel slippage. However, if the torque converter's lock-up mechanism is open, the hydraulic transmission method will struggle to achieve rapid and precise speed control, resulting in poor anti-slip performance. Summary of the Invention

[0004] This application provides a vehicle speed control method, device, storage medium, and vehicle to solve the problem that new energy vehicles equipped with hydraulic torque converters are currently unable to achieve fast and accurate speed control under slippage conditions.

[0005] To solve the above problems, this application adopts the following technical solution:

[0006] In a first aspect, embodiments of this application provide a vehicle speed control method, the method comprising:

[0007] When the vehicle is slipping, determine the target output shaft speed of the transmission output shaft and the target motor speed of the motor, and obtain the working status of the hydraulic torque converter lock-up mechanism.

[0008] When the working state is in the open state, the target hydraulic pressure value of the transmission clutch is determined based on the target output shaft speed and the current output shaft speed of the transmission output shaft;

[0009] Based on the target hydraulic value, the transmission clutch is controlled to switch from the closed state to the slipping state in order to perform speed regulation operation on the transmission output shaft;

[0010] When the motor meets the motor speed regulation conditions, the motor speed is regulated based on the target motor speed and the current motor speed.

[0011] In one embodiment of this application, the step of determining the target output shaft speed of the transmission output shaft and the target motor speed of the motor includes:

[0012] Determine the target rotational speed of the target wheel;

[0013] The target output shaft speed is determined based on the target rotational speed and the first gear ratio between the target wheel and the transmission output shaft;

[0014] The target motor speed is determined based on the target output shaft speed and the second gear ratio between the transmission output shaft and the motor.

[0015] In one embodiment of this application, the step of determining the target rotational speed of the target wheel includes:

[0016] Determine the driver's current driving intention and the current road surface adhesion coefficient;

[0017] Based on the current driving intention and the current road surface adhesion coefficient, determine the optimal slip ratio of the target wheel;

[0018] Based on the optimal slip ratio, the target rotational speed of the target wheel is determined.

[0019] In one embodiment of this application, after the step of obtaining the working state of the hydraulic torque converter lock-up mechanism, the method further includes:

[0020] When the working state is locked, the hydraulic torque converter locking mechanism is controlled to switch from the locked state to the open state.

[0021] In one embodiment of this application, the method further includes:

[0022] When the vehicle is slipping, if an accelerator pedal signal is detected, the torque required by the driver corresponding to the accelerator pedal signal is determined to be a preset value.

[0023] In one embodiment of this application, after determining the target output shaft speed of the transmission output shaft and the target motor speed of the motor when the vehicle is in a slipping condition, the method further includes:

[0024] If the current output shaft speed of the transmission output shaft is greater than the target output shaft speed, it is determined that the motor meets the motor speed regulation conditions.

[0025] In one embodiment of this application, before the step of adjusting the speed of the motor based on the target motor speed and the current motor speed when the motor meets the motor speed adjustment conditions, the method further includes:

[0026] Obtain the current control mode of the motor;

[0027] If the current control mode is not the speed control mode, control the motor to switch from the current control mode to the speed control mode.

[0028] Secondly, based on the same inventive concept, embodiments of this application provide a vehicle speed control device, the device comprising:

[0029] The speed determination module is used to determine the target output shaft speed of the transmission output shaft and the target motor speed of the motor when the vehicle is in a slipping condition, and to obtain the working status of the hydraulic torque converter lock-up mechanism.

[0030] The hydraulic value determination module is used to determine the target hydraulic value of the transmission clutch based on the target output shaft speed and the current output shaft speed of the transmission output shaft when the working state is in the open state.

[0031] The clutch control module is used to control the transmission clutch to switch from a closed state to a slipping state based on the target hydraulic value, so as to perform speed regulation operation on the transmission output shaft;

[0032] The motor speed control module is used to perform speed control operation on the motor based on the target motor speed and the current motor speed, provided that the motor meets the motor speed control conditions.

[0033] In one embodiment of this application, the rotational speed determination module includes:

[0034] The wheel speed determination submodule is used to determine the target rotational speed of the target wheel;

[0035] The output shaft speed determination submodule is used to determine the target output shaft speed based on the target speed and the first gear ratio between the target wheel and the transmission output shaft;

[0036] The motor speed determination submodule is used to determine the target motor speed based on the target output shaft speed and the second gear ratio between the transmission output shaft and the motor.

[0037] In one embodiment of this application, the wheel speed determination submodule includes:

[0038] The information determination unit is used to determine the driver's current driving intention and the current road surface adhesion coefficient;

[0039] The optimal slip ratio determination unit is used to determine the optimal slip ratio of the target wheel based on the current driving intention and the current road surface adhesion coefficient;

[0040] The target rotational speed determination unit is used to determine the target rotational speed of the target wheel based on the optimal slip ratio.

[0041] In one embodiment of this application, the vehicle speed control device further includes:

[0042] The state control module is used to control the hydraulic torque converter locking mechanism to switch from the locked state to the open state when the working state is the locked state.

[0043] In one embodiment of this application, the vehicle speed control device further includes:

[0044] The torque determination module is used to determine the driver's required torque corresponding to the accelerator pedal signal as a preset value when the vehicle is in a slipping condition and an accelerator pedal signal is detected.

[0045] In one embodiment of this application, the vehicle speed control device further includes:

[0046] The speed regulation condition determination module is used to determine that the motor meets the motor speed regulation condition when the current output shaft speed of the transmission output shaft is greater than the target output shaft speed.

[0047] In one embodiment of this application, the vehicle speed control device further includes:

[0048] A control mode acquisition module is used to acquire the current control mode of the motor;

[0049] The control mode switching module is used to control the motor to switch from the current control mode to the speed control mode when the current control mode is not the speed control mode.

[0050] Thirdly, based on the same inventive concept, embodiments of this application provide a storage medium storing machine-executable instructions, which, when executed by a processor, implement the vehicle speed control method proposed in the first aspect of this application.

[0051] Fourthly, based on the same inventive concept, embodiments of this application provide a vehicle including a processor and a memory, wherein the memory stores machine-executable instructions that can be executed by the processor, and the processor is used to execute the machine-executable instructions to implement the vehicle speed control method proposed in the first aspect of this application.

[0052] Compared with the prior art, this application has the following advantages:

[0053] This application provides a vehicle speed control method that, when the vehicle is slipping, determines the target output shaft speed of the transmission output shaft and the target motor speed, and obtains the working state of the torque converter lock-up mechanism. When the locking mechanism is in the open state, based on the target output shaft speed and the current output shaft speed of the transmission, the method determines the target hydraulic pressure value of the transmission clutch. Then, based on the target hydraulic pressure value, it controls the transmission clutch to switch from the closed state to the slipping state to adjust the speed of the transmission output shaft. Simultaneously, when the motor meets the motor speed control conditions, it adjusts the motor speed based on the target motor speed and the current motor speed. This application embodiment, by controlling the transmission clutch to adjust the speed of the transmission output shaft based on the target hydraulic pressure value when the torque converter lock-up mechanism is in the open state, can quickly reduce the transmission output shaft speed. Simultaneously, based on the target motor speed, it controls the motor speed, enabling rapid and precise speed control through dual speed control of the transmission and motor when the vehicle is slipping, thereby effectively improving the vehicle's anti-slip performance. Attached Figure Description

[0054] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0055] Figure 1 This is a schematic diagram of the steps of a vehicle speed control method in one embodiment of this application.

[0056] Figure 2 This is a schematic diagram of a speed regulation system according to one embodiment of this application.

[0057] Figure 3 This is a schematic diagram of the functional modules of a vehicle speed control device according to an embodiment of this application.

[0058] Figure 4 This is a structural schematic diagram of a vehicle according to one embodiment of this application. Detailed Implementation

[0059] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0060] It should be noted that a hydraulic torque converter, also known as a "hydraulic torque converter," "turbo torque converter," or "hydrodynamic torque converter," is a hydraulic component mainly composed of a pump impeller, a turbine, a stator, and a locking mechanism (usually a lock-up clutch), using hydraulic oil as its working medium. The pump impeller is connected to the vehicle's engine, the turbine is connected to the transmission, and the locking mechanism has two operating states: open and locked.

[0061] In the open state, the turbine and pump impeller are separated. The engine drives the pump impeller to rotate, which in turn drives the turbine by agitating the hydraulic oil in the torque converter. The guide wheel, located between the pump impeller and turbine, adjusts the direction of the hydraulic oil. Because power is transmitted between the turbine and pump impeller via hydraulic oil, a soft connection between the engine and transmission is achieved, reducing the dynamic load on the transmission system, ensuring smooth vehicle starts, and increasing vehicle power through the speed difference between the pump impeller and turbine. However, when the speed difference between the pump impeller and turbine is approximately the same during vehicle operation, if hydraulic oil is still needed to drive the turbine, it would lead to higher energy consumption. To reduce energy consumption, when the vehicle reaches higher speeds, the locking mechanism can be locked. The torque converter locks the pump impeller and turbine through the locking mechanism, rigidly connecting them. This allows the pump impeller to directly transmit power to the turbine instead of through hydraulic oil, thus reducing energy consumption.

[0062] In other words, when the vehicle is traveling at a higher speed, the locking mechanism is usually in the locked state; when the vehicle is traveling at a lower speed or starting, the locking mechanism is usually in the unlocked state.

[0063] In related technologies, when a vehicle experiences wheel slippage, a drive anti-slip function is triggered. This function reduces the torque output of the power source to prevent wheel slippage. After the drive anti-slip function is activated, the chassis typically calculates the target torque, which is then arbitrated by the chassis's torque coordination module before being output to the vehicle controller. The vehicle controller then sends the target torque to the motor, which responds by reducing torque. This signal transmission and coordination process takes more than 50ms, resulting in a slow response speed for the drive anti-slip function. Furthermore, for new energy vehicles equipped with hydraulic torque converters, if the torque converter's locking mechanism is open when wheel slippage occurs, the traditional speed regulation method based on torque reduction control will struggle to achieve rapid and precise speed control, leading to poor anti-slip performance.

[0064] To address the problem of rapid and precise speed control in new energy vehicles equipped with hydraulic torque converters under slippage conditions, this application aims to provide a vehicle speed control method. By controlling the transmission clutch to a slipping state based on a target hydraulic value when the hydraulic torque converter lock-up mechanism is in the open state, the transmission output shaft speed can be rapidly reduced. Simultaneously, the motor speed is controlled based on a target motor speed. This dual speed control of the transmission and motor enables rapid and precise speed control when the vehicle slips, thereby effectively improving the vehicle's anti-slip performance.

[0065] Reference Figure 1 This application illustrates a vehicle speed control method, which may include the following steps:

[0066] S101: When the vehicle is in a slipping condition, determine the target output shaft speed of the transmission output shaft and the target motor speed of the motor, and obtain the working status of the hydraulic torque converter lock-up mechanism.

[0067] It should be noted that the executing entity in this embodiment can be a computing service device with data processing, network communication, and program execution functions, or an electronic device with the above functions, such as a vehicle computer, on-board computer, ECU (Electronic Control Unit), TCU (Transmission Control Unit), VCU (Vehicle Control Unit), etc. To improve the response time of speed control and achieve rapid control of the torque converter and transmission output shaft speeds, this embodiment will use the TCU as the executing entity. It should be noted that this embodiment does not impose specific limitations on the executing entity of the vehicle.

[0068] In this embodiment, refer to Figure 2 This diagram illustrates a speed control system according to this application. The speed control system includes a power system, a TCU (Transmission Control Unit), a chassis controller, a torque converter, a transmission, and wheels. The vehicle's power system is connected to the wheels sequentially via the torque converter and the transmission. The power system can be a hybrid system consisting of an engine and an electric motor, in which case the engine is connected to the torque converter via the electric motor; alternatively, the power system can be a pure electric system consisting of an electric motor, in which case the electric motor is connected to the torque converter. The TCU is connected to the electric motor, the torque converter, and the transmission. The chassis controller is connected to both the electric motor and the TCU.

[0069] In this embodiment, the chassis controller is used to detect the wheel speed in real time to determine whether the vehicle is in a slipping condition. When it is determined that the vehicle is in a slipping condition, the anti-slip function is activated, and an anti-slip function activation signal is sent to the TCU and the motor so that the TCU and the motor can control the speed.

[0070] In its implementation, the chassis controller monitors the vehicle's current speed and the current wheel speed of the target wheels (the drive wheels connected to the vehicle's powertrain). Based on these speeds, it determines the vehicle's current slip ratio. If the current slip ratio exceeds a slip ratio threshold and its duration exceeds a duration threshold, the vehicle is considered to be in a slipping condition. By monitoring the duration of slippage, brief slippage during driving can be ignored, preventing frequent triggering of the anti-slip function. It should be noted that the TCU can also be connected to wheel speed and vehicle speed sensors to directly detect slippage.

[0071] In this embodiment, after determining that the vehicle is in a slipping condition, the TCU will calculate the target output shaft speed of the transmission output shaft and the target motor speed of the motor. These target output shaft speeds and target motor speeds represent the expected speeds at which the vehicle will not slip. Simultaneously, the TCU will also acquire the operating status of the torque converter lock-up mechanism to determine whether the lock-up mechanism is in the open state.

[0072] In this embodiment, if the TCU detects that the operating state is locked, it will control the torque converter lock-up mechanism to switch from the locked state to the open state. By controlling the torque converter lock-up mechanism to switch to the open state, the power transmission between the motor and the transmission can be quickly cut off, so that the drive torque output by the motor cannot be effectively transmitted to the transmission, thereby facilitating the TCU to achieve rapid control of the transmission output shaft speed.

[0073] S102: When the working state is open, determine the target hydraulic pressure value of the transmission clutch based on the target output shaft speed and the current output shaft speed of the transmission output shaft.

[0074] In this embodiment, if the TCU detects that the hydraulic torque converter lock-up mechanism is in the open state, it will obtain the current output shaft speed of the transmission output shaft, and then determine the target hydraulic pressure value of the transmission clutch based on the current output shaft speed and the desired target output shaft speed through closed-loop control.

[0075] In practical implementation, PI (proportional-integral) control can be used to achieve closed-loop control of the target hydraulic value. Specifically, the TCU has a built-in proportional controller and an integral controller. The TCU first calculates the first speed difference between the current output shaft speed and the target output shaft speed, and then inputs the current output shaft speed and the first speed difference into the proportional controller to output the proportionally adjusted hydraulic value; the current output shaft speed and the first speed difference are input into the integral controller to output the integral adjusted hydraulic value; and then, based on the proportionally adjusted hydraulic value and the integral adjusted hydraulic value, the target hydraulic value of the transmission clutch is determined.

[0076] In this embodiment, by performing closed-loop control on the transmission clutch, the target hydraulic value required by the transmission clutch can be calculated in real time, thereby enabling rapid and precise control of the transmission output shaft speed through the transmission clutch.

[0077] S103: Based on the target hydraulic value, control the transmission clutch to switch from the closed state to the slipping state in order to perform speed regulation operation on the transmission output shaft.

[0078] In this embodiment, after calculating the target hydraulic pressure value, the TCU will control the hydraulic pressure of the transmission clutch based on the target hydraulic pressure value to keep the transmission clutch in a slipping state. The target hydraulic pressure value is less than a critical hydraulic pressure value, which represents the minimum hydraulic pressure value required to close the transmission clutch.

[0079] In this embodiment, by controlling the hydraulic pressure of the transmission clutch, the transmission input shaft and the transmission output shaft can be kept in a slip-grip state, thereby achieving the purpose of rapidly reducing the speed of the transmission output shaft.

[0080] S104: When the motor meets the motor speed regulation conditions, perform speed regulation operation on the motor based on the target motor speed and the current motor speed.

[0081] In this embodiment, during the process of the TCU controlling the speed of the transmission output shaft, it will also determine in real time whether the motor meets the motor speed regulation conditions; if the motor is detected to meet the motor speed regulation conditions, the motor will be controlled to control its speed so that the current motor speed is quickly reduced to the target motor speed.

[0082] In the specific implementation, considering that if the current output shaft speed decreases to the target output shaft speed, it means that the target wheel can exit the slippage condition, the motor speed regulation condition can be set as follows: the current output shaft speed of the transmission output shaft is greater than the target output shaft speed. In other words, the motor speed regulation condition is determined to be met when the current output shaft speed of the transmission output shaft is greater than the target output shaft speed.

[0083] In practice, after the TCU or chassis controller calculates the target motor speed, it sends a motor control command containing the target motor speed to the motor controller, so that the motor controller can perform PI regulation of the motor based on the target motor speed and the current motor speed through a preset PI regulation strategy.

[0084] In this embodiment, by performing closed-loop control on the motor, the motor can quickly complete the torque reduction operation, thereby rapidly adjusting the motor speed to the target motor speed.

[0085] It should be noted that if the motor is detected as not meeting the motor speed regulation conditions, or if the current motor speed decreases to the target motor speed, the motor is considered to have completed the torque reduction and speed regulation operation. The speed regulation for the motor is then discontinued, and a speed regulation completion signal is sent back to the chassis controller. Based on this signal, the chassis controller then disengages the traction control function. After the traction control function disengages, the torque converter and transmission clutch will switch to their respective target states based on the vehicle's current driving needs to maintain normal vehicle operation.

[0086] In this embodiment, by controlling the speed of the transmission output shaft to decrease to the target output shaft speed and controlling the current motor speed to decrease to the target motor speed, the current wheel speed of the target wheel connected to the transmission output shaft can be reduced rapidly, thereby enabling the vehicle to exit the slipping condition and achieving a rapid and effective response of the drive anti-slip function.

[0087] This embodiment of the application, by logically calculating the target hydraulic value when the vehicle is in a slipping condition and the hydraulic torque converter lock-up mechanism is in the open state, and controlling the transmission clutch to switch to a slipping state, can achieve closed-loop control of the transmission output shaft speed, thereby achieving the purpose of quickly reducing the transmission output shaft speed. At the same time, by logically calculating the target motor speed and performing closed-loop speed control on the motor speed, dual speed control of the transmission and motor can be achieved when the vehicle is slipping, realizing fast and precise speed control. Compared with the traditional speed regulation method of calculating the target torque through the chassis controller and then controlling the motor to reduce torque through the vehicle controller, it can not only shorten the control response time of the drive anti-slip function, but also effectively improve the anti-slip effect of the vehicle and improve the user experience.

[0088] In one feasible implementation, the step of determining the target output shaft speed of the transmission output shaft and the target motor speed in S101 may specifically include the following sub-steps:

[0089] S101-1: Determine the target rotational speed of the target wheel.

[0090] In this embodiment, the target rotational speed of the target wheel can be determined based on the current vehicle speed. For example, if the vehicle is detected to be in a slipping condition, the target vehicle speed is determined based on the difference between the current vehicle speed and the preset vehicle speed reduction gradient. Then, the target rotational speed of the target wheel is determined based on the preset conversion relationship between vehicle speed and wheel rotational speed.

[0091] It should be noted that the target rotational speed represents the wheel speed at which the target wheel can exit the slipping condition.

[0092] S101-2: Determine the target output shaft speed based on the target speed and the first gear ratio between the target wheel and the transmission output shaft.

[0093] In this embodiment, since the target wheel and the transmission output shaft are rigidly connected, the target output shaft speed of the transmission output shaft can be determined based on the target speed and the first gear ratio. That is, the target output shaft speed represents the speed at which the target wheel can reach the target speed.

[0094] S101-3: Determine the target motor speed based on the target output shaft speed and the second gear ratio between the transmission output shaft and the motor.

[0095] In this embodiment, since the transmission output shaft and the motor are softly connected when the locking mechanism of the hydraulic torque converter is in the open state, the second gear ratio between the transmission output shaft and the motor can be pre-calibrated when the hydraulic torque converter is in the open state. Then, based on the target output shaft speed and the second gear ratio, the target motor speed can be further calculated. That is, the target motor speed represents the speed at which the target wheel can reach the target speed through the transmission of components such as the hydraulic torque converter and the transmission.

[0096] In this embodiment, by fully considering the first gear ratio and the second gear ratio, the desired target output shaft speed of the transmission output shaft and the desired target motor speed of the motor can be accurately calculated.

[0097] In one feasible implementation, to achieve accurate calculation of the target rotational speed, S101-1 may specifically include the following sub-steps:

[0098] S101-1-1: Determine the driver's current driving intention and the current road surface adhesion coefficient.

[0099] It should be noted that the target speed is related to both driving intention and road surface adhesion coefficient. Specifically, under the same conditions, the higher the road surface adhesion coefficient, the higher the target speed will be. To meet different driving intentions, different target speeds can be matched to different driving intentions. For example, considering that vehicles are more prone to loss of control when turning, the target speed corresponding to slippage when the driver turns can be set to be lower than the target speed corresponding to slippage when driving straight.

[0100] In practical implementation, driving intentions include, but are not limited to, accelerating, decelerating, turning left, turning right, and going straight. Considering that the driver may have one or more of the aforementioned driving intentions during vehicle operation, vehicle status information collected by various devices such as vehicle acceleration sensors, steering wheel angle sensors, accelerator pedals, and wheel speed sensors can be acquired, and then the driver's current driving intention can be determined based on the vehicle status information.

[0101] In practical implementation, the road surface adhesion coefficient can be determined based on the vehicle's current longitudinal and lateral acceleration collected by the accelerometer, the steering wheel angle signal collected by the steering wheel angle sensor, and the vehicle's current slip ratio. Specifically, the current longitudinal acceleration, current lateral acceleration, steering wheel angle signal, and current slip ratio can be input into a pre-established support vector regression model to output the current road surface adhesion coefficient.

[0102] S101-1-2: Determine the optimal slip ratio of the target wheel based on the current driving intention and the current road surface adhesion coefficient.

[0103] In this embodiment, the optimal slip ratio of the target wheel can be determined by looking up a table. Specifically, a mapping table representing the correspondence between different road surface adhesion coefficients and the optimal slip ratio under different driving intentions can be pre-constructed. Then, after determining the current driving intention and the current road surface adhesion coefficient, the corresponding optimal slip ratio can be determined by looking up the mapping table.

[0104] It should be noted that all vehicles will experience a certain degree of slippage during normal driving. A moderate degree of slippage is beneficial for normal vehicle operation. The optimal slip ratio indicates the point at which the adhesion between the wheels and the road surface is greatest, resulting in the greatest braking force and the best braking effect.

[0105] S101-1-3: Determine the target rotational speed of the target wheel based on the optimal slip ratio.

[0106] In this embodiment, after determining the optimal slip ratio, the target rotational speed of the target wheel can be calculated by combining the vehicle's current speed.

[0107] In this embodiment, by comprehensively considering driving intention and road surface adhesion coefficient, the target rotational speed can be accurately calculated, so that the target output shaft speed and target motor speed calculated based on the target rotational speed can be closer to the ideal speed, thereby further improving the accuracy of transmission and motor speed control.

[0108] In one feasible implementation, the vehicle speed control method may further include the following steps:

[0109] S201: When the vehicle is in a slippery condition, if an accelerator pedal signal is detected, the torque required by the driver corresponding to the accelerator pedal signal will be determined as a preset value.

[0110] In this embodiment, after the TCU or chassis controller detects that the vehicle is in a slipping condition, it will send a drive anti-slip function activation signal to the VCU. After receiving the drive anti-slip function activation signal, the VCU will no longer respond to the torque request triggered by the driver. That is, if the VCU detects an accelerator pedal signal, regardless of the accelerator pedal travel indicated by the accelerator pedal signal, it will determine the torque required by the driver corresponding to the accelerator pedal signal as a preset value, which can be set to 0.

[0111] For example, after receiving the drive anti-slip function activation signal, if the VCU detects that the accelerator pedal signal corresponds to a driver's required torque of 500 N·m, the VCU will not send the 500 N·m torque request to the power system. Instead, it will correct the driver's required torque to 0 before sending it to the power system. This will prevent the motor from outputting torque according to the driver's required torque, thereby ensuring that the motor speed can be smoothly adjusted while effectively preventing the vehicle's slippage from further increasing due to driver misoperation, thus ensuring vehicle driving safety.

[0112] In one feasible implementation, prior to S104, the vehicle speed control method may further include the following steps:

[0113] S301: Obtain the current control mode of the motor.

[0114] It should be noted that, to ensure the motor meets diverse usage requirements, different control modes will be set based on its intended application. For example, when the motor needs to output torque to drive the vehicle, it needs to switch to torque control mode; when the motor is used for power generation, it needs to switch to voltage control mode; and when the motor needs to regulate speed, it needs to switch to speed control mode. It should also be noted that the motor may have other control modes as well.

[0115] In this embodiment, in order to enable the motor to perform stable speed regulation, the current control mode of the motor will be obtained before the TCU controls the motor to perform speed regulation operation, so as to determine whether the control mode needs to be switched.

[0116] S302: When the current control mode is not the speed control mode, control the motor to switch from the current control mode to the speed control mode.

[0117] In practice, after the TCU detects that the current control mode of the motor is not the speed control mode, it will send a mode switching request to the motor controller so that the motor controller can respond to the mode switching request and switch the motor from the current control mode to the speed control mode.

[0118] In this embodiment, by switching the motor to speed control mode in advance, the motor speed can be adjusted to the target motor speed more stably and quickly when the motor is adjusted.

[0119] Secondly, based on the same inventive concept, and referring to... Figure 3 This application provides a vehicle speed control device 300, which includes:

[0120] The speed determination module 301 is used to determine the target output shaft speed of the transmission output shaft and the target motor speed of the motor when the vehicle is in a slipping condition, and to obtain the working status of the hydraulic torque converter lock-up mechanism.

[0121] Hydraulic value determination module 302 is used to determine the target hydraulic value of the transmission clutch based on the target output shaft speed and the current output shaft speed of the transmission output shaft when the working state is open;

[0122] The clutch control module 303 is used to control the transmission clutch to switch from a closed state to a slipping state based on a target hydraulic value, so as to perform speed regulation operation on the transmission output shaft;

[0123] The motor speed control module 304 is used to adjust the speed of the motor based on the target motor speed and the current motor speed, provided that the motor meets the motor speed control conditions.

[0124] In one embodiment of this application, the rotational speed determination module 301 includes:

[0125] The wheel speed determination submodule is used to determine the target rotational speed of the target wheel;

[0126] The output shaft speed determination submodule is used to determine the target output shaft speed based on the target speed and the first gear ratio between the target wheel and the transmission output shaft;

[0127] The motor speed determination submodule is used to determine the target motor speed based on the target output shaft speed and the second gear ratio between the transmission output shaft and the motor.

[0128] In one embodiment of this application, the wheel speed determination submodule includes:

[0129] The information determination unit is used to determine the driver's current driving intention and the current road surface adhesion coefficient;

[0130] The optimal slip ratio determination unit is used to determine the optimal slip ratio of the target wheel based on the current driving intention and the current road surface adhesion coefficient.

[0131] The target speed determination unit is used to determine the target speed of the target wheel based on the optimal slip ratio.

[0132] In one embodiment of this application, the vehicle speed control device 300 further includes:

[0133] The state control module is used to control the hydraulic torque converter locking mechanism to switch from the locked state to the open state when the working state is locked.

[0134] In one embodiment of this application, the vehicle speed control device 300 further includes:

[0135] The torque determination module is used to determine the driver's required torque corresponding to the accelerator pedal signal as a preset value when the vehicle is in a slipping condition and an accelerator pedal signal is detected.

[0136] In one embodiment of this application, the vehicle speed control device 300 further includes:

[0137] The speed regulation condition determination module is used to determine whether the motor meets the motor speed regulation conditions when the current output shaft speed of the transmission output shaft is greater than the target output shaft speed.

[0138] In one embodiment of this application, the vehicle speed control device 300 further includes:

[0139] The control mode acquisition module is used to acquire the current control mode of the motor.

[0140] The control mode switching module is used to switch the motor from the current control mode to the speed control mode when the current control mode is not the speed control mode.

[0141] It should be noted that the specific implementation of the vehicle speed control device 300 in this application embodiment refers to the specific implementation of the vehicle speed control method proposed in the first aspect of the above-mentioned application embodiment, and will not be repeated here.

[0142] Thirdly, based on the same inventive concept, embodiments of this application provide a storage medium storing machine-executable instructions, which, when executed by a processor, implement the vehicle speed control method proposed in the first aspect of this application.

[0143] It should be noted that the specific implementation of the storage medium in the embodiments of this application refers to the specific implementation of the vehicle speed control method proposed in the first aspect of this application, and will not be repeated here.

[0144] Thirdly, based on the same inventive concept, and referring to... Figure 4 The illustration shows an embodiment of the present application that provides a vehicle 400, including a processor 401 and a memory 402; the memory 402 stores machine-executable instructions that can be executed by the processor 401, and the processor 401 is used to execute the machine-executable instructions to implement the vehicle speed control method proposed in the first aspect of the present application.

[0145] It should be noted that the specific implementation of the vehicle 400 in this application embodiment refers to the specific implementation of the vehicle speed control method proposed in the first aspect of this application, and will not be repeated here.

[0146] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, apparatus, or computer program products. Therefore, embodiments of the present invention can take the form of entirely hardware embodiments, entirely software embodiments, or embodiments combining software and hardware aspects. Furthermore, embodiments of the present invention can take the form of computer program products implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0147] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, terminal devices (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing terminal device to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing terminal device, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0148] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing terminal device to operate in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0149] These computer program instructions can also be loaded onto a computer or other programmable data processing terminal equipment, causing a series of operational steps to be performed on the computer or other programmable terminal equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable terminal equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0150] Although preferred embodiments of the present invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of the embodiments of the present invention.

[0151] Finally, it should be noted that in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or terminal device 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 terminal device. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or terminal device that includes the element.

[0152] The present invention provides a detailed description of a vehicle speed control method, device, storage medium, and vehicle. Specific examples have been used to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the present invention. At the same time, those skilled in the art will recognize that, based on the ideas of the present invention, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A vehicle speed control method, characterized in that, The method includes: When the vehicle is slipping, determine the target output shaft speed of the transmission output shaft and the target motor speed of the motor, and obtain the working status of the hydraulic torque converter lock-up mechanism. When the working state is in the open state, the target hydraulic pressure value of the transmission clutch is determined based on the target output shaft speed and the current output shaft speed of the transmission output shaft; Based on the target hydraulic value, the transmission clutch is controlled to switch from the closed state to the slipping state in order to perform speed regulation operation on the transmission output shaft; When the motor meets the motor speed regulation conditions, the motor speed is regulated based on the target motor speed and the current motor speed.

2. The vehicle speed control method according to claim 1, characterized in that, The steps for determining the target output shaft speed of the transmission output shaft and the target motor speed include: Determine the target rotational speed of the target wheel; The target output shaft speed is determined based on the target rotational speed and the first gear ratio between the target wheel and the transmission output shaft; The target motor speed is determined based on the target output shaft speed and the second gear ratio between the transmission output shaft and the motor.

3. The vehicle speed control method according to claim 2, characterized in that, The steps to determine the target rotational speed of the target wheel include: Determine the driver's current driving intention and the current road surface adhesion coefficient; Based on the current driving intention and the current road surface adhesion coefficient, determine the optimal slip ratio of the target wheel; Based on the optimal slip ratio, the target rotational speed of the target wheel is determined.

4. The vehicle speed control method according to claim 1, characterized in that, After obtaining the operating state of the hydraulic torque converter lock-up mechanism, the method further includes: When the working state is locked, the hydraulic torque converter locking mechanism is controlled to switch from the locked state to the open state.

5. The vehicle speed control method according to claim 1, characterized in that, The method further includes: When the vehicle is slipping, if an accelerator pedal signal is detected, the torque required by the driver corresponding to the accelerator pedal signal is determined to be a preset value.

6. The vehicle speed control method according to claim 1, characterized in that, After determining the target output shaft speed of the transmission output shaft and the target motor speed when the vehicle is in a slipping condition, the method further includes: If the current output shaft speed of the transmission output shaft is greater than the target output shaft speed, it is determined that the motor meets the motor speed regulation conditions.

7. The vehicle speed control method according to claim 1, characterized in that, Before the step of adjusting the speed of the motor based on the target motor speed and the current motor speed, when the motor meets the motor speed regulation conditions, the method further includes: Obtain the current control mode of the motor; If the current control mode is not the speed control mode, control the motor to switch from the current control mode to the speed control mode.

8. A vehicle speed control device, characterized in that, The device includes: The speed determination module is used to determine the target output shaft speed of the transmission output shaft and the target motor speed of the motor when the vehicle is in a slipping condition, and to obtain the working status of the hydraulic torque converter lock-up mechanism. The hydraulic value determination module is used to determine the target hydraulic value of the transmission clutch based on the target output shaft speed and the current output shaft speed of the transmission output shaft when the working state is in the open state. The clutch control module is used to control the transmission clutch to switch from a closed state to a slipping state based on the target hydraulic value, so as to perform speed regulation operation on the transmission output shaft; The motor speed control module is used to perform speed control operation on the motor based on the target motor speed and the current motor speed, provided that the motor meets the motor speed control conditions.

9. A storage medium, characterized in that, The storage medium stores machine-executable instructions, which, when executed by a processor, implement the vehicle speed control method as described in any one of claims 1-7.

10. A vehicle, characterized in that, It includes a processor and a memory, the memory storing machine-executable instructions that can be executed by the processor, the processor executing the machine-executable instructions to implement the vehicle speed control method as described in any one of claims 1-7.

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