Torque control method and device of vehicle and vehicle

Abstract

The invention provides a torque control method and device of a vehicle and the vehicle. A first difference value torque is obtained according to the original rear axle demand torque of a driver and the request torque of the distributed traction control system, the front axle demand torque is adjusted according to the first difference value torque, the lost torque of the rear axle is compensated to the front axle, it is guaranteed that the torque of the whole vehicle is not reduced, front wheels have enough torque, and the large escape capacity can be achieved; the smoothness of vehicle driving is ensured, and the driving experience is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of vehicles, and in particular to a vehicle torque control method, a vehicle torque control device, and a vehicle. Background Art

[0002] The Distributed Traction Control (DTCS) system, located within the chassis' Integrated Brake Controller (IBC), is primarily used in electric vehicles and hybrid electric vehicles powered by electric motors. Compared to traditional internal combustion engines, electric motors deliver greater energy and dynamic performance during acceleration due to their rapid electromagnetic induction and high torque at low speeds. This makes electric vehicles more susceptible to wheel slip on low-grip surfaces.

[0003] For vehicles with a four-wheel drive architecture, when the rear wheels slip, the rear wheel torque cannot be output, resulting in the loss of the vehicle's torque request capability.

[0004] Therefore, when the rear wheels of a vehicle slip, how to ensure smooth driving of the vehicle is an urgent problem that needs to be solved. Summary of the Invention

[0005] In view of this, the embodiments of the present invention are dedicated to providing a vehicle torque control method, device and vehicle. By compensating the torque lost on the rear axle to the front axle, the torque of the entire vehicle will not be reduced, which can ensure the smoothness of vehicle driving and improve the driving experience.

[0006] In a first aspect, an embodiment of the present application provides a vehicle torque control method, which is applied to a vehicle controller. The method includes: when a distributed traction control system is activated, obtaining a requested torque of the distributed traction control system; obtaining a first difference torque based on the driver's original rear axle requested torque and the requested torque of the distributed traction control system; and adjusting the front axle requested torque based on the first difference torque.

[0007] In an embodiment of the present application, a first difference torque is obtained based on the original rear axle demand torque and the requested torque of the DTCS when the distributed traction control system is activated, and the torque lost due to rear wheel slip is obtained. The front axle demand torque is adjusted according to the first difference torque to compensate the torque lost due to rear wheel slip to the front axle, thereby increasing the front axle torque and keeping the torque request capacity of the whole vehicle unchanged, so that the front wheels have sufficient torque, that is, they have sufficient escape capability, thereby ensuring the smoothness of vehicle driving and improving the driving experience.

[0008] Optionally, a first differential torque is obtained based on the driver's original rear axle demand torque and the distributed traction control system's requested torque, including: obtaining the vehicle's gear position; if the vehicle is in R gear, obtaining the negative value of the distributed traction control system's requested torque, and calculating the difference between the driver's original rear axle demand torque and the negative value to obtain a second differential torque; if the vehicle is in D gear, calculating the difference between the driver's original rear axle demand torque and the distributed traction control system's requested torque to obtain a second differential torque; and determining the first differential torque based on the second differential torque.

[0009] In this embodiment of the present application, the first differential torque is calculated in conjunction with the vehicle's gear position. When the vehicle is in R gear, the distributed traction control system's requested torque is first negative, and the difference between the original rear axle demand torque and the negative value is calculated to obtain the second differential torque. When the vehicle is in D gear, the difference between the original rear axle demand torque and the distributed traction control system's requested torque is directly calculated to obtain the second differential torque. The first differential torque is then determined based on the second differential torque. This calculation of the first differential torque in conjunction with the vehicle's gear position accurately determines the torque lost by the rear motor due to slip, thereby facilitating the subsequent accurate compensation of the rear motor's lost torque to the front axle.

[0010] Optionally, determining the first differential torque based on the second differential torque includes: if the second differential torque is greater than a first threshold, determining that the first differential torque is equal to the second differential torque; if the second differential torque is less than or equal to the first threshold, determining that the first differential torque is zero.

[0011] In an embodiment of the present application, a first threshold is set for the torque lost on the rear axle, and the second differential torque is assigned to the first differential torque only when the second differential torque is greater than the first threshold. Subsequently, the torque lost on the rear axle can be compensated to the front axle based on the first differential torque. When the second differential torque is less than or equal to the first threshold, the first differential torque is assigned to 0. In this way, the rear axle torque can be controlled to be compensated to the front axle only when necessary, which can improve the efficiency of torque control.

[0012] Optionally, adjusting the front axle demand torque according to the first differential torque includes: determining and obtaining the driver's original vehicle demand torque; calculating the difference between the original vehicle demand torque and the original rear axle demand torque to obtain the original front axle demand torque; and obtaining the adjusted front axle demand torque according to the first differential torque and the original front axle demand torque.

[0013] In the embodiment of the present application, the first differential torque is obtained based on the torque lost on the rear axle, which is the torque that needs to be compensated to the front axle to keep the torque of the entire vehicle unchanged. The adjusted front axle demand torque is obtained based on the first differential torque and the original front axle demand torque. The adjusted front axle demand torque takes into account the original front axle demand torque and the torque lost by the rear motor due to rear wheel slippage, which can ensure that the torque of the entire vehicle will not decrease, the front wheels have sufficient torque, and can have a greater ability to escape from difficulties, thereby ensuring the smoothness of vehicle driving and improving the driving experience.

[0014] Optionally, obtaining the adjusted front axle required torque according to the first difference torque and the original front axle required torque includes: calculating the sum of the first difference torque and the original front axle required torque to obtain the adjusted front axle required torque.

[0015] In the embodiment of the present application, the sum of the first differential torque and the original front axle required torque is used as the adjusted front axle required torque, so that the first differential torque lost by the rear motor is superimposed on the front axle, which can ensure that the torque of the entire vehicle will not decrease. In this way, the front wheels have sufficient torque and can have a greater ability to escape from difficulties, thereby ensuring the smoothness of vehicle driving and improving the driving experience.

[0016] Optionally, the adjusted front axle demand torque is obtained based on the first difference torque and the original front axle demand torque, including: determining the current driving mode of the vehicle; if the driving mode is a preset driving mode, calculating the sum of the first difference torque and the original front axle demand torque to obtain the adjusted front axle demand torque.

[0017] In the embodiment of the present application, the torque lost by the rear motor is transferred to the front axle in combination with the driving mode control. The torque compensation operation can be performed only when the vehicle is in a preset driving mode where compensation is required. This can improve the efficiency of torque control and at the same time achieve torque transfer more accurately, ensuring that the torque of the entire vehicle will not decrease, ensuring that the front wheels have sufficient torque to get out of trouble, ensuring the smoothness of vehicle driving, and improving the driving experience.

[0018] Optionally, the method further includes: if the distributed traction control system is not activated, or the driving mode is not a preset driving mode, determining the adjusted front axle required torque to be the original front axle required torque.

[0019] In the embodiment of the present application, the efficiency of torque control can be improved by directly maintaining the original front axle required torque unchanged in the case where torque compensation is not required.

[0020] In a second aspect, an embodiment of the present application further provides a vehicle torque control device, which is applied to a vehicle controller. The device includes: a torque acquisition module, which is used to obtain the requested torque of the distributed traction control system when the distributed traction control system is activated; a difference calculation module, which is used to obtain a first difference torque based on the driver's original rear axle required torque and the requested torque of the distributed traction control system; and a torque control module, which is used to adjust the front axle required torque based on the first difference torque.

[0021] In a third aspect, an embodiment of the present application further provides a vehicle, comprising a vehicle body and a controller, the controller being configured to execute the steps of the aforementioned method.

[0022] In a fourth aspect, an embodiment of the present invention provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed, the method as described above is implemented.

[0023] By means of the above technical solution, an embodiment of the present invention provides a vehicle torque control method, device and vehicle, which are applied to a vehicle controller. When the distributed traction control system is activated, a first differential torque is obtained based on the driver's original rear axle demand torque and the distributed traction control system's requested torque, and the front axle demand torque is adjusted based on the first differential torque. The first differential torque lost on the rear axle is compensated to the front axle, ensuring that the torque of the entire vehicle does not decrease, the front wheels have sufficient torque, can have a greater escape ability, ensure the smoothness of vehicle driving, and enhance the driving experience.

[0024] The above description is only an overview of the technical solution of the present disclosure. In order to more clearly understand the technical means of the present disclosure, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present disclosure more obvious and easy to understand, the specific implementation methods of the present disclosure are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The above and other purposes, features, and advantages of the present application will become more apparent through a more detailed description of the embodiments of the present application in conjunction with the accompanying drawings. The accompanying drawings are intended to provide a further understanding of the embodiments of the present application and constitute a part of the specification. Together with the embodiments of the present application, they are used to explain the present application and do not constitute a limitation of the present application. In the drawings, the same reference numerals generally represent the same components or steps.

[0026] Figure 1 Shown is a schematic diagram of a power architecture of a vehicle provided by one embodiment of the present application;

[0027] Figure 2 Shown is a control schematic diagram of a distributed traction control system provided by one embodiment of the present application;

[0028] Figure 3FIG2 is a flow chart of a vehicle torque control method provided by one embodiment of the present application;

[0029] Figure 4 Shown is an example diagram of torque control of a vehicle provided by one embodiment of the present application;

[0030] Figure 5 FIG2 is a schematic structural diagram of a vehicle torque control device provided by one embodiment of the present application;

[0031] Figure 6 Shown is a schematic structural diagram of a vehicle provided in one embodiment of the present application. DETAILED DESCRIPTION

[0032] Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0033] The vehicle's powertrain architecture is shown in Figure 1 The vehicle 100 includes a front motor 101, a coupling 102, a clutch 103, an engine 104, a front axle transmission 105, a front differential 106, a left front wheel 107, a right front wheel 108, a rear motor 109, a rear axle transmission 110, a rear differential 111, a left rear wheel 112 and a right rear wheel 113.

[0034] A front motor 101 is mounted on the front axle, providing power to left and right front wheels 107, 108 via a front drive shaft, thereby driving vehicle 110. The front motor 101 is connected to a clutch 103 via a coupling 102. The first end of the clutch 103 is connected to the engine 104, and the second end of the clutch 104 is connected to the first end of a front axle transmission 105. The second end of the front axle transmission 105 is connected to a front differential 106, which is positioned between the left and right front wheels 107, 108. The front axle torque is the sum of the front motor torque and the engine torque.

[0035] A rear motor 109 is provided on the rear axle, and is used to provide power to a left rear wheel 112 and a right rear wheel 113 via a rear drive propeller shaft to drive the vehicle 110. The rear motor 109 is connected to a first end of a rear axle transmission 110, and a second end of the rear axle transmission 110 is connected to a rear differential 111, which is provided between the left rear wheel 112 and the right rear wheel 113. The rear axle torque is equal to the rear motor torque.

[0036] The distributed traction control system (DTCS), located within the chassis' integrated brake controller (IBC), is primarily used in electric vehicles and hybrid vehicles powered by electric motors. It is an improved version of the traditional traction control system (TCS), sharing the same operating principles and system components: sensors, decision-makers, and actuators. Compared to traditional internal combustion engines, electric motors, due to their rapid electromagnetic induction and high torque at low speeds, provide the drive wheels with greater energy and dynamics during acceleration. This makes the drive wheels of electric vehicles more susceptible to slip on low-grip surfaces. Using wheel speed sensors, steering wheel angle sensors, and body yaw sensors, the TCS monitors the driver's driving intent, road conditions, and wheel dynamics. If a risk to vehicle stability due to drive wheel slip is detected, precise torque control is implemented to prevent the wheel slip, ensuring safe and stable driving. The longer target torque control cycle of traditional TCS exacerbates this dynamic behavior. The DTCS (Dynamic Motor Control, DMC) system encapsulates the "torque control unit" algorithm within the motor control unit (MCU) to shorten the control cycle, for example, from 100ms to 10ms. This effectively prevents the risk of vehicle instability during acceleration caused by large dynamic movements of the drive wheels. In short, both the TCS function and the more responsive DTCS system essentially reduce the motor's torque during rapid acceleration to prevent slip and maintain stability.

[0037] For vehicles with four-wheel drive architecture, the control of the distributed traction control system is as follows: Figure 2When the rear wheels slip, the Electronic Stability Program (ESP) sends a Distributed Traction Control System (DTCS) activation request (DTCS_RA) to the Rear Drive Motor Control Unit (RMCU), activating the DTCS. ESP then transmits the rear axle torque (i.e., intervention torque) associated with the DTCS_RA activation request directly to the Rear Drive Motor Control Unit (RMCU). The RMCU responds quickly, driving the corresponding rear motor M to stop the rear wheels from slipping. At this point, the vehicle is primarily driven by the front wheels, but the front wheel torque is less than the overall vehicle torque, which can lead to insufficient front wheel escape capability. In a traditional TCS, the intervention torque from the ESP system is sent to the Vehicle Control Unit (VCU), which then transmits it to the rear-drive motor controller (RMCU), front-drive motor controller (FMCU), and engine control module (ECM). This results in CAN bus transmission delays on the VCU. In a distributed traction control system (DTCS), when DTCS_RA is activated, the rear-drive motor controller (RMCU) listens to the ESP system and ignores the torque request from the VCU. This reduces the rear motor's torque, resulting in a loss of vehicle torque capability. In this situation, the front wheels are primarily driven, while the front-drive motor controller (FMCU) and engine control module (ECM) listen to the VCU's torque request and drive the corresponding motor M based on the VCU's torque request. The torque loss on the rear axle is not transferred to the front axle, resulting in front-wheel torque less than the overall vehicle torque, which can lead to insufficient front-wheel escape capability.

[0038] Based on this, the embodiment of the present application provides a flow chart of a vehicle torque control method. The vehicle torque control method is applied to the vehicle controller. Figure 3 As shown, the torque control method of the vehicle includes:

[0039] Step S11: When the distributed traction control system is activated, the requested torque of the distributed traction control system is obtained.

[0040] It is understood that rear wheel slip can occur on the left rear wheel, the right rear wheel, or both. Rear wheel slip can hinder rear axle torque output, resulting in a decrease in vehicle torque output while maintaining front axle torque, potentially hindering vehicle extrication. For example, when a vehicle is traveling on difficult roads, both the front and rear axles must function as power sources to ensure smooth and normal driving. This is typically the case when the vehicle is in any of the following driving modes: Eco, Normal, Sport, Snow, Mud, Sand, or AWD. If at least one rear wheel slips, the actual rear axle torque output may decrease, and may even result in a loss of torque output. Although front axle torque remains unchanged, vehicle power is comprised of both front and rear axle torque. The lack of rear axle torque reduces vehicle torque output, leading to insufficient vehicle power, uneven driving, and a difficulty in achieving smooth and normal driving, with insufficient power to support the vehicle's extrication.

[0041] In an embodiment of the present application, when the rear wheels slip, the distributed traction control system (DTCS) is activated, the requested torque of the distributed traction control system (DTCS) is obtained, and the vehicle stability control system (ESP) outputs the requested torque of the distributed traction control system (DTCS) to the rear drive motor controller (RMCU). The rear drive motor controller (RMCU) responds quickly and controls the rear motor torque to be reduced to the requested torque. It should be noted that the requested torque is the DTCS_RA requested torque at the shaft end, and the requested torque can be switched to the wheel end. Specifically, the DTCS_RA requested torque at the shaft end is multiplied by the rear axle speed ratio to obtain the DTCS_RA requested torque at the wheel end. The wheel-end rear motor torque is then controlled to be reduced to the requested torque switched to the wheel end. The requested torque is the actual output torque that the rear drive motor controller (RMCU) controls the rear motor to output when the rear wheels slip.

[0042] Step S12: Obtain a first differential torque according to the driver's original rear axle demand torque and the distributed traction control system's requested torque.

[0043] Before rear wheel slip, the torque output by the rear wheels is the driver's original rear axle torque request. After rear wheel slip, the activated Distributed Traction Control System (DTCS) controls the actual output torque of the rear electric motor to become the DTCS's requested torque, which is less than the original rear axle torque request. A first differential torque is then derived based on the original rear axle torque request and the DTCS's requested torque. Specifically, if the vehicle is in D gear, the difference between the requested torque and the original rear axle torque request is calculated; this difference is the first differential torque.

[0044] In some embodiments of the present application, the driver's original rear axle torque demand is the original rear axle torque demand at the wheel end. A first differential torque can be obtained based on the driver's original rear axle torque demand and the requested torque switched to the wheel end, combined with the vehicle gear information. This first differential torque is the torque lost by the vehicle due to rear wheel slip, that is, the torque that needs to be transferred to the front axle to maintain vehicle power. For example, if the vehicle is in D gear and the original rear axle torque demand is 1000 NM, when the rear wheels slip, the distributed traction control system (DTCS) is activated, and the rear drive motor controller (RMCU) responds to the request of the distributed traction control system (DTCS) and controls the rear motor to output the distributed traction control system (DTCS) requested torque of 400 NM. The calculated first differential torque is the difference between 1000 NM and 400 NM, that is, 600 NM.

[0045] Step S13: Adjusting the front axle required torque according to the first difference torque.

[0046] The front axle torque requirement is adjusted based on the first differential torque lost at the rear axle due to rear wheel slip, compensating for the lost torque on the front axle. Specifically, the first differential torque is added to the original front axle torque requirement to create the adjusted front axle torque requirement. This adds the lost torque to the front axle, maintaining the overall vehicle torque. This means the vehicle's power remains unchanged, while the front axle has sufficient power to escape the skid.

[0047] The torque control method of the vehicle in the embodiment of the present application obtains a first difference torque based on the original rear axle demand torque and the requested torque of the distributed traction control system (DTCS), obtains the torque lost due to rear wheel slip, and adjusts the front axle demand torque based on the first difference torque, so that the torque lost due to rear wheel slip is compensated to the front axle, thereby increasing the front axle torque, and the torque request capacity of the whole vehicle remains unchanged, so that the front wheels have sufficient torque, that is, they have sufficient escape capability, thereby ensuring the smoothness of vehicle driving and improving the driving experience.

[0048] Considering that the driver's original rear axle torque request is always positive, regardless of the vehicle's gear position, while the positive or negative sign of the DTCS torque request is related to the vehicle's gear position, when the vehicle is in D, the DTCS torque request is positive. When the vehicle is in R, the DTCS torque request is negative. For example, the absolute value of the DTCS torque request is 400. Thus, if the vehicle is in R, the DTCS torque request is -400, and if the vehicle is in D, the DTCS torque request is 400. To accurately determine the torque lost to the rear axle due to rear wheel slip, embodiments of the present application utilize the vehicle's gear position to determine a first differential torque. Alternatively, the vehicle's gear position is determined; if the vehicle is in R, the negative value of the DTCS torque request is determined, and the difference between the driver's original rear axle torque request and the negative value is calculated to determine a second differential torque. If the vehicle is in D gear, the difference between the driver's original rear axle torque demand and the torque requested by the Distributed Traction Control System (DTCS) is calculated to obtain a second differential torque. The first differential torque is then determined based on the second differential torque. This second differential torque represents the torque lost by the rear electric motor. If the vehicle is in R gear, the DTCS torque request is multiplied by -1, and the resulting value is subtracted from the original rear axle torque demand to obtain the second differential torque. If the vehicle is in D gear, the difference between the original rear axle torque demand and the DTCS torque request is directly calculated to obtain the second differential torque. For example, if the original rear axle demand torque is 1000 NM and the vehicle is in R gear and the DTCS torque request is -400 NM, the negative value of the DTCS torque request is first obtained, resulting in 400. The difference between the original rear axle demand torque and the negative value of the DTCS torque request is then calculated: 1000 - 400 = 600, resulting in a second differential torque of 600 NM. If the vehicle is in D gear, the difference between the original rear axle demand torque and the DTCS torque request is directly calculated: 1000 - 400 = 600, resulting in a second differential torque of 600 NM. This difference is calculated by subtracting the absolute values of the original rear axle demand torque and the DTCS torque request to obtain the second differential torque. The first differential torque is then determined directly based on the obtained second differential torque. By calculating the first differential torque in combination with the vehicle gear position, the torque lost by the rear motor due to slip can be accurately obtained, thereby facilitating the subsequent accurate compensation of the torque lost by the rear motor to the front axle.

[0049] Considering that if the torque loss of the rear axle due to rear wheel slip is very small, the reduction in the vehicle's torque is not enough to affect the vehicle's normal driving. At this time, the front axle still has sufficient ability to escape from trouble, and the vehicle can still run normally without compensating the torque lost by the rear axle to the front axle. The small torque loss of the rear axle can be due to the slight slip of the rear wheel, so the torque loss of the rear motor is small and not enough to affect the vehicle's normal driving. It can also be due to the original rear axle demand torque allocated to the rear motor when the vehicle is running normally, and the front axle torque is relatively large. In this way, even if the rear axle torque is completely lost, it is not enough to affect the front wheel's ability to escape from trouble, nor does it affect the vehicle's normal driving. At this time, the torque loss of the rear axle does not need to be compensated to the front axle to ensure the vehicle's normal driving. Therefore, the numerical value of the first differential torque lost by the rear axle can be judged, and then the first differential torque that needs to be transferred to the front axle can be determined.

[0050] Based on this, in some embodiments of the present application, if the second differential torque is greater than a first threshold, the first differential torque is determined to be equal to the second differential torque. If the second differential torque is less than or equal to the first threshold, the first differential torque is determined to be zero. If the second differential torque is greater than the first threshold, it indicates that the rear motor has suffered a significant loss of torque, resulting in a significant loss of the vehicle's torque request capability. This can lead to insufficient front wheel escape capability, affecting vehicle smoothness and requiring compensation for the rear axle's lost torque to ensure normal driving. In this case, the second differential torque is determined to be equal to the first differential torque, assigning the actual torque loss of the rear axle to the first differential torque, facilitating subsequent transfer of all the rear motor's lost torque to the front axle. It should be noted that the first threshold is intended to measure whether torque loss caused by rear motor slip will result in insufficient front wheel escape capability, affecting normal vehicle driving. If the second differential torque is less than or equal to the first threshold, it indicates that the rear motor has suffered a minimal loss of torque, and transfer of the rear motor's lost torque to the front axle is not necessary, allowing the vehicle to travel normally. The first threshold can be pre-calibrated based on experience, for example, to 0.1 Nm. By setting a first threshold for the torque lost on the rear axle, the second differential torque is assigned to the first differential torque only when the second differential torque is greater than the first threshold. Subsequently, the torque lost on the rear axle can be compensated to the front axle based on the first differential torque. When the second differential torque is less than or equal to the first threshold, the first differential torque is assigned to 0. In this way, the rear axle torque can be controlled to be compensated to the front axle only when necessary, which can improve the efficiency of torque control.

[0051] After obtaining the first differential torque required to compensate the front axle, a torque compensation operation is subsequently performed. Specifically, in some embodiments of the present application, the driver's original vehicle torque requirement is determined; the difference between the original vehicle torque requirement and the original rear axle torque requirement is calculated to obtain the original front axle torque requirement; and an adjusted front axle torque requirement is obtained based on the first differential torque and the original front axle torque requirement. For example, if the original vehicle torque requirement is 2000 NM and the original vehicle torque requirement is 1000 NM, the original front axle torque requirement is the difference between 2000 NM and 1000 NM, which is equal to 1000 NM. If the first differential torque is 600 NM, the adjusted front axle torque requirement is the sum of 1000 NM and 600 NM, which is 1600 NM. The first differential torque is obtained based on the torque lost on the rear axle, and is the torque that needs to be compensated to the front axle to keep the torque of the entire vehicle unchanged. The adjusted front axle demand torque is obtained based on the first differential torque and the original front axle demand torque. The adjusted front axle demand torque takes into account the original front axle demand torque and the torque lost by the rear motor due to rear wheel slippage, which can ensure that the torque of the entire vehicle will not decrease, the front wheels have sufficient torque, and can have a greater ability to escape from difficulties, thereby ensuring the smoothness of vehicle driving and improving the driving experience.

[0052] In some embodiments of the present application, the adjusted front axle required torque can be directly calculated based on the first differential torque and the original front axle required torque without considering other conditions of the vehicle. Optionally, the sum of the first differential torque and the original front axle required torque is calculated to obtain the adjusted front axle required torque. When the distributed traction control system (DTCS) is activated and the rear wheels slip, the distributed traction control system (DTCS) controls the rear motor to reduce torque. At this time, in order not to affect the normal driving of the vehicle and ensure the smoothness of vehicle driving, it is necessary to transfer the torque lost by the rear motor to the front axle so that the torque of the entire vehicle will not be reduced. Adjusting the front axle required torque to the sum of the first differential torque and the original front axle required torque, that is, superimposing the first differential torque lost by the rear motor on the front axle, can ensure that the torque of the entire vehicle will not be reduced. In this way, the front wheels have sufficient torque and can have a greater ability to escape from difficulties, ensuring the smoothness of vehicle driving and improving the driver's driving experience.

[0053] Taking into account different driving modes, there are differences in vehicle dynamics. In some driving modes, the rear wheels do not slip, which has no effect on the normal driving of the vehicle, and there is no need to consider compensating the rear axle loss torque to the front axle. In some driving modes, the torque lost on the rear axle cannot be compensated to the front axle. For example, in a two-wheel drive mode, if it is a rear-wheel drive mode, the front wheels are not drive wheels, and the torque lost on the rear axle cannot be compensated to the front axle. If it is a front-wheel drive mode, the rear axle is not a drive wheel, the power of the whole vehicle has nothing to do with the rear axle torque, and the torque lost on the rear wheels will not affect the driving of the whole vehicle. Based on this, in some embodiments of the present application, the impact of the driving mode on it is considered when performing torque compensation. Optionally, the current driving mode of the vehicle is determined; if the distributed traction control system (DTCS) is activated and the driving mode is a preset driving mode, the sum of the first difference torque and the original front axle required torque is calculated to obtain the adjusted front axle required torque.

[0054] A selectable list (MAP) can be provided, including all selectable driving modes. When determining the driving mode, it is simply determined whether the vehicle's current driving mode is one of the listed modes. If so, torque compensation is performed; if not, torque compensation is not performed. The selection of a preset driving mode is primarily based on whether rear motor torque loss would affect normal vehicle operation and whether the rear motor torque can be compensated to the front axle. For example, if the current driving mode is front-wheel drive (FWD) in a two-wheel drive system, the rear wheels do not have a driving function. Even if the rear wheels slip, there is no torque loss, and no torque compensation is required. Of course, in other embodiments of the present application, the preset driving mode can be left blank, indicating that the impact of the driving mode is not considered. By combining driving mode control to transfer torque lost by the rear motor to the front axle, torque compensation is performed only when the vehicle is in the preset driving mode requiring compensation. This improves torque control efficiency and enables more accurate torque transfer, ensuring that the overall vehicle torque does not decrease, ensuring sufficient torque for the front wheels to escape, and ensuring a smooth and enhanced driving experience.

[0055] Considering that when the distributed traction control system (DTCS) is inactive, the rear motor responds to the VCU's rear axle torque request, for example, at 1000 Nm. Even if the rear wheels slip, the rear motor's output torque remains unchanged at 1000 Nm, and the vehicle's overall output torque remains unchanged. The torque lost due to rear wheel slip is therefore immeasurable, and compensation for the rear motor's lost torque to the front axle is impossible. However, if the driving mode is not the preset driving mode, this indicates that the rear motor torque lost due to rear wheel slip in this driving mode will not affect normal vehicle operation, and torque compensation is not required. Based on this, in some embodiments of the present application, if the distributed traction control system (DTCS) is inactive or the driving mode is not the preset driving mode, the adjusted front axle demand torque is determined to be the original front axle demand torque, the original front axle demand torque remains unchanged, and no torque compensation is performed. This allows the original front axle demand torque to remain unchanged in situations where torque compensation is not required, thereby improving torque control efficiency.

[0056] Figure 4 The complete torque control method of the present application is shown. Figure 4 As shown, 1 minus the front axle ratio yields the rear axle ratio, and the product of the original vehicle torque demand and the rear axle ratio yields the driver's original rear axle torque demand. The driver's original rear axle torque demand is subtracted from the original vehicle torque demand to yield the driver's original front axle torque demand. If DTCS_RA is not activated or the driving mode is not a preset driving mode, the first data selector U1 selects the No path, and the adjusted front axle torque demand equals the driver's original rear axle torque demand. This means that the front axle does not compensate for rear axle torque losses, and the front axle torque demand remains unchanged.

[0057] When DTCS_RA is activated, regardless of the driving mode or the preset driving mode, the first data selector U1 is controlled to select the Yes path, requiring the rear axle torque loss to be transferred to the front axle. At this time, if the vehicle is in D gear, the second data selector U2 is controlled to select the Yes path, calculating the difference between the driver's original rear axle torque demand and the DTCS_RA requested torque to obtain a second differential torque for the rear axle loss. This second differential torque is compared with a first threshold. If this second differential torque is greater than the first threshold, the third data selector U3 is controlled to select the Yes path, requiring the first differential torque to be compensated to the front axle to be equal to the second differential torque, i.e., the first differential torque represents the actual torque loss at the rear axle. The adjusted front axle torque demand is equal to the sum of the first differential torque and the original front axle torque demand—that is, the sum of the difference between the driver's original rear axle torque demand and the DTCS_RA requested torque and the driver's original front axle torque demand. If the second differential torque is less than or equal to the first threshold, it means that the rear motor has not lost torque or the lost torque is small, and no torque transfer is required. The third data selector U3 is controlled to select the No path, and the first differential torque that needs to be compensated to the front axle is assigned to zero. The adjusted front axle demand torque is equal to the original front axle demand torque plus 0, that is, the original front axle demand torque remains unchanged.

[0058] If the vehicle is not in the D gear, the second data selector U2 is controlled to select the No path, and then further determines whether the vehicle is in the R gear. If the vehicle is in the R gear, the fourth data selector U4 is controlled to select the Yes path, and the difference between the driver's original rear axle demand torque and the negative value of the DTCS_RA request torque is calculated to obtain the second differential torque lost by the rear axle. The second differential torque is compared with the first threshold. If the second differential torque is greater than the first threshold, the fifth data selector U5 is controlled to select the Yes path, and the first differential torque to be compensated to the front axle is equal to the second differential torque, that is, the first differential torque is the torque actually lost by the rear axle. The adjusted front axle demand torque is equal to the sum of the first differential torque and the original front axle demand torque, that is, the sum of the difference between the driver's original rear axle demand torque and the negative value of the DTCS_RA request torque and the driver's original front axle demand torque. Similarly, if the second differential torque is less than or equal to the first threshold, it means that the rear motor has not lost torque or the lost torque is small, and no torque transfer is required. The fifth data selector U5 is controlled to select the No path, and the first differential torque that needs to be compensated to the front axle is assigned to zero. The adjusted front axle demand torque is equal to the original front axle demand torque plus 0, that is, the original front axle demand torque remains unchanged.

[0059] Table 1 below provides an example comparing different torque control methods. When DTCS_RA is inactive, meaning no torque reduction control is applied to the rear motor, the VCU-requested front axle torque and the VCU-requested rear motor torque remain at 1000 Nm, and the vehicle torque remains at 2000 Nm. When dTCS_RA is active but no torque transfer control is applied, the dTCS_RA-requested torque is 400 Nm, which controls the actual torque of the rear motor to 400 Nm. At this point, the VCU-requested front axle torque remains at 1000 Nm, and the vehicle torque is reduced to 1600 Nm. This reduction in vehicle torque can easily lead to insufficient front axle escape capability.

[0060] Table 1 Comparison of different torque control methods

[0061]

[0062] dTCS_RA is activated, and torque transfer control is performed simultaneously, that is, applying the torque control method of this application. The torque requested by dTCS_RA is 400Nm, that is, the actual torque of the rear motor is controlled to be reduced to 400Nm, and the rear motor loses 1000Nm-400Nm=600Nm. At this time, the front axle torque requested by the VCU is controlled to be 1000Nm+600Nm=1600Nm, that is, the actual front axle torque is 1600Nm, increasing the front axle's ability to escape from difficulties. In this way, the total vehicle torque is 1600Nm+400Nm=2000Nm, that is, the total vehicle torque remains unchanged, ensuring vehicle driving smoothness and improving the driving experience.

[0063] In summary, an embodiment of the present invention provides a vehicle torque control method, which is applied to a vehicle controller. When the distributed traction control system (DTCS) is activated, a first differential torque is obtained based on the driver's original rear axle demand torque and the distributed traction control system (DTCS) request torque, and the front axle demand torque is adjusted based on the first differential torque. The first differential torque lost on the rear axle is compensated to the front axle to ensure that the torque of the entire vehicle does not decrease, the front wheels have sufficient torque, and can have a greater escape ability, thereby ensuring the smoothness of vehicle driving and improving the driving experience.

[0064] Figure 5 FIG. 1 is a schematic diagram of a vehicle torque control device according to an embodiment of the present application. The vehicle torque control device is applied to a vehicle controller, such as Figure 5 As shown, the torque control device 50 of the vehicle includes:

[0065] The torque acquisition module 501 is used to acquire the requested torque of the distributed traction control system when the distributed traction control system is activated;

[0066] a difference calculation module 502 for obtaining a first difference torque according to the original rear axle demand torque of the driver and the requested torque of the distributed traction control system;

[0067] The torque control module 503 is configured to adjust the front axle required torque according to the first difference torque.

[0068] In some embodiments, the difference calculation module 502 is used to: obtain the gear position of the vehicle; if the vehicle is in gear R, obtain the negative value of the requested torque of the distributed traction control system, and calculate the difference between the driver's original rear axle required torque and the negative value to obtain a second difference torque; if the vehicle is in gear D, calculate the difference between the driver's original rear axle required torque and the requested torque of the distributed traction control system to obtain a second difference torque; and determine the first difference torque based on the second difference torque.

[0069] In some embodiments, the difference calculation module 502 is further configured to: determine that the first difference torque is equal to the second difference torque if the second difference torque is greater than a first threshold; and determine that the first difference torque is zero if the second difference torque is less than or equal to the first threshold.

[0070] In some embodiments, the torque control module 503 is also used to: determine and obtain the driver's original vehicle demand torque; calculate the difference between the original vehicle demand torque and the original rear axle demand torque to obtain the original front axle demand torque; and obtain the adjusted front axle demand torque based on the first difference torque and the original front axle demand torque.

[0071] In some embodiments, the torque control module 503 is further configured to calculate the sum of the first difference torque and the original front axle required torque to obtain an adjusted front axle required torque.

[0072] In some embodiments, the torque control module 503 is further used to: determine the current driving mode of the vehicle; if the driving mode is a preset driving mode, calculate the sum of the first difference torque and the original front axle required torque to obtain the adjusted front axle required torque.

[0073] In some embodiments, the torque control module 503 is further configured to: if the distributed traction control system is not activated or the driving mode is not a preset driving mode, determine the adjusted front axle required torque to be the original front axle required torque.

[0074] The specific definitions of the vehicle torque control device can be found in the definitions of the vehicle torque control method described above and will not be further elaborated here. Each module in the aforementioned vehicle torque control device may be implemented in whole or in part via software, hardware, or a combination thereof. Each of these modules may be embedded in or independent of a processor within a computer device in hardware form, or may be stored in a computer device memory in software form, allowing the processor to call and execute the corresponding operations of each module.

[0075] Regarding the device in the above embodiment, the specific manner in which each unit performs the operation has been described in detail in the embodiment of the vehicle torque control method, and will not be elaborated here.

[0076] Figure 6 It is a structural schematic diagram of a vehicle provided in an embodiment of the present application.

[0077] For example, Figure 6 As shown, the vehicle includes: a memory 601 and a processor 602, wherein the memory 601 stores an executable program code 6011, and the processor 602 is used to call and execute the executable program code 6011 to implement the vehicle torque control method.

[0078] This embodiment can divide the vehicle into functional modules based on the above-mentioned method embodiment. For example, each functional module can be mapped to a specific function, or two or more functions can be integrated into a single processing module. The integrated module can be implemented in hardware. It should be noted that the module division in this embodiment is illustrative and represents only a logical functional division. In actual implementation, other division methods may be used.

[0079] In the case of dividing the functional modules according to the respective functions, the vehicle may include: a torque acquisition module, a difference calculation module, a torque control module, and the like.

[0080] It should be noted that all relevant contents of each step involved in the above method embodiment can be referred to the functional description of the corresponding functional module and will not be repeated here.

[0081] The vehicle provided in this embodiment is used to execute the torque control method of the vehicle described above, and thus can achieve the same effect as the above-mentioned implementation method.

[0082] In the case of an integrated unit, the vehicle may include a processing module and a storage module. The processing module may be used to control and manage the vehicle's movements, while the storage module may be used to support the vehicle's execution of program codes and data.

[0083] The processing module may be a processor or controller that implements or executes various exemplary logic blocks, modules, and circuits disclosed herein. The processor may also be a combination that implements computing functions, such as a combination of one or more microprocessors, a combination of a digital signal processing system (DSP) and a microprocessor, and the storage module may be a memory.

[0084] An embodiment of the present invention also provides a computer-readable storage medium, which stores computer program code. When the computer program code runs on a computer, the computer executes the above-mentioned related method steps to implement a vehicle torque control method provided by the above embodiment. Among them, computer-readable storage media may include, but are not limited to, any type of disk, including floppy disks, optical disks, DVDs (Digital Video Discs), CD-ROMs (Compact Disc Read-Only Memory), microdrives and magneto-optical disks, ROMs (Read-Only Memory), RAMs (Random Access Memory), EPROMs (Erasable Programmable Read-Only Memory), EEPROMs (Electrically Erasable Programmable Read Only Memory), DRAMs (Dynamic Random Access Memory), VRAMs (Video Random Access Memory), flash memory devices, magnetic or optical cards, nanosystems (including molecular memory ICs), or any type of medium or device suitable for storing instructions and / or data.

[0085] The present application also provides a computer program product. When the computer program product is run on a computer, it enables the computer to execute the above-mentioned related steps to implement a vehicle torque control method in the above-mentioned embodiment.

[0086] Among them, the beneficial effects of the above embodiments can refer to the beneficial effects of the corresponding methods provided above, and will not be repeated here.

[0087] Through the description of the above implementation methods, technical personnel in the relevant field can understand that for the convenience and simplicity of description, only the division of the above-mentioned functional modules is used as an example. In actual applications, the above-mentioned functions can be distributed and completed by different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above.

[0088] In the embodiments provided in this application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are merely schematic. For example, the division of modules or units is only a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another device, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0089] In the description of the present disclosure, it should be understood that if the terms "up", "down", "front", "back", "left" and "right" are used to indicate directions or positional relationships, they are based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the positions or elements referred to must have a specific direction, be constructed and operate in a specific direction. Therefore, they should not be understood as limitations of the present disclosure.

[0090] It should be noted that, in the embodiments of the present application, relational terms such as first and second, etc. are merely used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply the existence of any such actual relationship or order between these entities or operations. It should also be noted that the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, commodity or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, commodity or device. In the absence of further restrictions, the elements defined by the statement "comprise a ..." do not exclude the presence of other identical elements in the process, method, commodity or device comprising the elements.

[0091] The above are merely examples of the present disclosure and are not intended to limit the present disclosure. Various modifications and variations are possible for those skilled in the art. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present disclosure are intended to be included within the scope of the claims of the present disclosure.

Claims

1. A method for controlling torque of a vehicle, characterized in that: Applied to a vehicle controller, the method includes: When a distributed traction control system is activated, obtaining a requested torque of the distributed traction control system; obtaining a first differential torque according to the original rear axle demand torque of the driver and the requested torque of the distributed traction control system; The front axle required torque is adjusted according to the first differential torque.

2. The torque control method according to claim 1, characterized in that: The obtaining of a first differential torque according to the original rear axle demand torque of the driver and the requested torque of the distributed traction control system includes: Get the gear position of the vehicle; If the vehicle is in gear R, obtaining a negative value of the requested torque of the distributed traction control system, and calculating a difference between the driver's original rear axle required torque and the negative value to obtain a second difference torque; If the vehicle is in gear D, the difference between the driver's original rear axle demand torque and the requested torque of the distributed traction control system is calculated to obtain a second difference torque; A first differential torque is determined based on the second differential torque.

3. The torque control method according to claim 2, characterized in that: Determining the first differential torque according to the second differential torque includes: If the second differential torque is greater than a first threshold, determining that the first differential torque is equal to the second differential torque; If the second differential torque is less than or equal to the first threshold, it is determined that the first differential torque is zero.

4. The torque control method according to claim 1, characterized in that: The adjusting the front axle required torque according to the first differential torque includes: Obtain the driver's original vehicle torque requirement; Calculating the difference between the original vehicle required torque and the original rear axle required torque to obtain the original front axle required torque; An adjusted front axle required torque is obtained according to the first difference torque and the original front axle required torque.

5. The torque control method according to claim 4, characterized in that: The step of obtaining the adjusted front axle required torque according to the first difference torque and the original front axle required torque includes: The sum of the first difference torque and the original front axle required torque is calculated to obtain an adjusted front axle required torque.

6. The torque control method according to claim 4, characterized in that: The step of obtaining the adjusted front axle required torque according to the first difference torque and the original front axle required torque includes: Determine the vehicle's current driving mode; If the driving mode is a preset driving mode, the sum of the first difference torque and the original front axle required torque is calculated to obtain an adjusted front axle required torque.

7. The torque control method according to claim 6, characterized in that: The method further comprises: If the distributed traction control system is not activated, or the driving mode is not the preset driving mode, the adjusted front axle demand torque is determined to be the original front axle demand torque.

8. A torque control device for a vehicle, characterized in that: Applied to a vehicle controller, the vehicle torque control device includes: a torque acquisition module, configured to acquire a requested torque of the distributed traction control system when the distributed traction control system is activated; a difference calculation module, configured to obtain a first difference torque according to an original rear axle demand torque of the driver and a request torque of the distributed traction control system; The torque control module is configured to adjust the required torque of the front axle according to the first difference torque.

9. A vehicle, characterized in that: The vehicle comprises: a memory for storing executable program code; A processor is configured to call and run the executable program code from the memory, so that the vehicle executes the method according to any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that The computer-readable storage medium stores a computer program, and when the computer program is executed, the method according to any one of claims 1 to 7 is implemented.

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