Torque distribution method, device and equipment of distributed driving system, automobile and storage medium

Abstract

The embodiment of the invention relates to the related technical field of vehicles, and discloses a torque distribution method, device and equipment of a distributed driving system, an automobile and a storage medium, a first shaft of the distributed driving system is driven by a single motor in a centralized mode, a second shaft is driven by double motors in a distributed mode, and the first shaft is a front shaft or a rear shaft; the method comprises the steps that torque distribution processing is carried out according to the expected yawing torque and the longitudinal target torque of the vehicle, and the first distribution torque and the second distribution torque of each driving motor are determined; and performing fusion processing on the first distribution torque and the second distribution torque of the driving motor, and determining a target torque of the driving motor. By means of the technical scheme, the problem that torque distribution in a distributed driving system is not reasonable enough in the prior art can be solved.

Description

Technical Field

[0001] The embodiments of the present invention relate to the field of vehicle-related technology, specifically to a torque distribution method, device, equipment, automobile, and storage medium for a distributed drive system. Background Technology

[0002] With the rapid development of electric vehicle technology, distributed drive systems are gradually becoming the mainstream configuration for high-end electric vehicles due to their significant improvement in lateral control capabilities. However, in existing technologies, the torque distribution for 1+2 distributed drive systems (front axle centralized drive + rear axle dual motor drive, or front axle dual motor drive + rear axle centralized drive) typically still adopts a four-wheel drive mode distribution strategy, which suffers from an unreasonable torque distribution and cannot optimally achieve the vehicle's lateral handling and longitudinal drive objectives simultaneously under various operating conditions and constraints. Summary of the Invention

[0003] In view of the above problems, embodiments of the present invention provide a torque distribution method, apparatus, device, vehicle and storage medium for a distributed drive system, which are used to solve the problem of unreasonable torque distribution in the prior art.

[0004] According to one aspect of the present invention, a torque distribution method for a distributed drive system is provided, wherein the first shaft of the distributed drive system uses a single-motor centralized drive and the second shaft uses a dual-motor distributed drive, and the first shaft is a front axle or a rear axle, the method comprising:

[0005] Based on the vehicle's expected yaw moment and longitudinal target torque, torque distribution processing is performed to determine the first and second distribution torques for each drive motor.

[0006] Wherein, the desired yaw moment represents the yaw moment expected by the user, determined based on the road surface adhesion coefficient of the current road surface, and the longitudinal target torque represents the driving torque expected by the user; the drive motor includes the main motor of the first axle, the left wheel motor and the right wheel motor of the second axle; the first allocated torque represents the torque allocated to achieve the desired yaw moment, and the second allocated torque represents the torque allocated to achieve the longitudinal target torque;

[0007] The first and second allocated torques of the drive motor are fused together to determine the target torque of the drive motor.

[0008] According to another aspect of the present invention, a torque distribution device for a distributed drive system is provided, wherein the first shaft of the distributed drive system uses a single-motor centralized drive and the second shaft uses a dual-motor distributed drive, and the first shaft is a front axle or a rear axle, the device comprising:

[0009] The first processing unit is used to perform torque distribution processing based on the vehicle's desired yaw moment and longitudinal target torque, and to determine the first and second distribution torques of each drive motor.

[0010] Wherein, the desired yaw moment represents the yaw moment expected by the user, determined based on the road surface adhesion coefficient of the current road surface, and the longitudinal target torque represents the driving torque expected by the user; the drive motor includes the main motor of the first axle, the left wheel motor and the right wheel motor of the second axle; the first allocated torque represents the torque allocated to achieve the desired yaw moment, and the second allocated torque represents the torque allocated to achieve the longitudinal target torque;

[0011] The second processing unit is used to fuse the first allocated torque and the second allocated torque of the drive motor to determine the target torque of the drive motor.

[0012] According to another aspect of the present invention, an electronic device is provided, including: a processor, a memory, a communication interface, and a communication bus, wherein the processor, the memory, and the communication interface communicate with each other through the communication bus;

[0013] The memory is used to store at least one executable instruction that causes the processor to perform the operation of the torque distribution method of the distributed drive system as described in any of the above.

[0014] According to another aspect of the present invention, a vehicle is provided, the vehicle including the electronic devices described above.

[0015] According to another aspect of the present invention, a computer-readable storage medium is provided, the storage medium storing at least one executable instruction that causes an electronic device / apparatus to perform the operation of the torque distribution method of the distributed drive system as described in any of the above embodiments.

[0016] This invention ensures the system's adaptability to actual road surfaces by making yaw moment decisions based on the road adhesion coefficient, significantly improving the anti-skid capability on low-adhesion roads. Furthermore, when distributing torque, the vehicle's yaw stability requirements are first decoupled from its longitudinal driving requirements, and then dynamically weighted and fused to achieve an adaptive balance between yaw control and longitudinal drive. This fully leverages the advantages of the hybrid drive architecture, enabling rapid response to emergency control commands while ensuring cruise efficiency and smoothness. While comprehensively improving vehicle safety, handling, and comfort, it also optimizes system load distribution and energy efficiency, enhances adaptability and reliability under all operating conditions, and effectively improves the rationality of torque distribution.

[0017] The above description is merely an overview of the technical solutions of the embodiments of the present invention. In order to better understand the technical means of the embodiments of the present invention and to implement them in accordance with the contents of the specification, and to make the above and other objects, features and advantages of the embodiments of the present invention more apparent and understandable, specific embodiments of the present invention are described below. Attached Figure Description

[0018] The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0019] Figure 1 A flowchart of a first embodiment of the torque distribution method for a distributed drive system provided by the present invention is shown;

[0020] Figure 2 A flowchart of another embodiment of the torque distribution method for a distributed drive system provided by the present invention is shown;

[0021] Figure 3 A flowchart of yet another embodiment of the torque distribution method for a distributed drive system provided by the present invention is shown;

[0022] Figure 4 This invention provides a schematic diagram of the structure of an embodiment of the torque distribution device for a distributed drive system.

[0023] Figure 5 A schematic diagram of an embodiment of the electronic device provided in this invention is shown. Detailed Implementation

[0024] Exemplary embodiments of the invention will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the invention are shown in the drawings, it should be understood that the invention can be implemented in various forms and should not be limited to the embodiments set forth herein.

[0025] To improve vehicle handling performance, an increasing number of electric vehicles are adopting a 1+2 distributed drive system for torque control. Currently, controlling the lateral performance of a 1+2 distributed drive system mainly involves two steps: calculating the desired yaw moment and distributing torque. However, the calculation of the desired yaw rate in existing technologies largely relies on vehicle state parameters (such as wheel angle and vehicle speed), lacking adaptability to the current driving scenario and potentially failing to suit different driving styles. Furthermore, existing torque distribution algorithms, when meeting the dual requirements of desired yaw moment and longitudinal target torque, typically still employ a four-wheel drive mode distribution strategy, making it difficult to achieve the optimal solution within the motor torque limit. This can easily lead to yaw control failure or insufficient longitudinal driving force, meaning that current torque distribution schemes are not yet sufficiently reasonable.

[0026] To address the aforementioned technical issues, this invention provides a torque distribution method for a distributed drive system. The method determines the desired yaw moment based on the driver's intention and the road surface adhesion coefficient. Simultaneously, a hierarchical torque distribution strategy is designed. First, the first and second allocated torques for each drive motor that satisfy the desired yaw moment and longitudinal target torque are calculated. Then, the first and second allocated torques are fused using a dynamic weighting factor. Ultimately, within the motor torque limit, synergistic optimization of yaw control and longitudinal driving force is achieved, improving the rationality of torque distribution and enhancing the personalization and safety of torque control.

[0027] The technical solution of the present invention and how the technical solution of the present invention solves the above-mentioned technical problems are described in detail below with specific embodiments. These specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments. The embodiments of the present invention will now be described with reference to the accompanying drawings.

[0028] It should be noted that the execution subject of the torque distribution method of the distributed drive system provided in the embodiments of the present invention can be the torque distribution device of the distributed drive system. The torque distribution device can be deployed on electronic devices such as vehicle controller, cockpit domain controller, and vehicle motion domain controller, and can coordinate with other controllers on the vehicle to achieve the torque distribution method of the distributed drive system of the present invention. The embodiments of the present invention do not limit the implementation of the method of the present invention, and it can be implemented by software, hardware or a combination of software and hardware.

[0029] Figure 1 A flowchart of a first embodiment of a torque distribution method for a distributed drive system provided by this invention is shown. This method can be executed by a torque distribution device. The distributed drive system in this embodiment includes a first axle and a second axle. The first axle uses a single-motor centralized drive (i.e., one main motor drives the entire axle), and the second axle uses a dual-motor distributed drive (i.e., a left wheel motor and a right wheel motor drive the left and right wheels respectively). The first axle can be a front axle or a rear axle, and correspondingly, the second axle can be a rear axle or a front axle. Figure 1 As shown, the method includes the following steps:

[0030] Step 110: Based on the vehicle's desired yaw moment and longitudinal target torque, perform torque distribution processing to determine the first and second distribution torques for each drive motor.

[0031] Among them, the expected yaw moment represents the yaw moment determined by the road surface adhesion coefficient of the current road surface and is expected by the user; the longitudinal target torque represents the driving torque expected by the user; the drive motor includes the main motor of the first shaft, the left wheel motor and the right wheel motor of the second shaft; the first allocated torque represents the torque allocated to achieve the expected yaw moment, and the second allocated torque represents the torque allocated to achieve the longitudinal target torque.

[0032] For example, before torque distribution, the torque distribution device pre-acquires the vehicle's desired yaw moment and longitudinal target torque. The desired yaw moment is calculated based on the current road surface adhesion coefficient and the driver's steering intentions and vehicle state. It reflects the driver's requirements for vehicle steering and driving stability and is typically estimated in real-time using sensors (such as steering wheel angle sensors and yaw rate sensors) and a vehicle state model (such as a two-degree-of-freedom vehicle model). The road surface adhesion coefficient can be obtained through tire force sensors or estimation algorithms to ensure that the yaw moment adjustment meets actual road surface requirements. The longitudinal target torque refers to the vehicle's driving or braking torque obtained from the driver's operating intentions, representing the driver's acceleration or deceleration needs. It is typically derived from signals from the accelerator pedal or brake pedal.

[0033] In this embodiment of the invention, the drive motor includes a main motor on the first shaft, a left wheel motor on the second shaft, and a right wheel motor. During torque distribution processing, the torque distribution device calculates a first distribution torque and a second distribution torque for each drive motor based on the desired yaw moment and the target longitudinal torque. The first distribution torque is the torque allocated to achieve the desired yaw moment; it is mainly generated by adjusting the torque difference between the left and right wheel motors on the second shaft, thereby affecting the vehicle's yaw motion. The second distribution torque is the torque allocated to achieve the target longitudinal torque, used to ensure that the overall acceleration or deceleration requirements of the vehicle are met; it is typically achieved by distributing the torques of the main motor on the first shaft and the dual motors on the second shaft.

[0034] In the specific allocation process, the torque distribution device can use a preset optimization algorithm (such as the least squares method) to distribute torque. For example, for the desired yaw moment, it is preferentially distributed through the dual motors on the second axis to quickly and independently adjust the torque of the left and right wheels, thereby efficiently generating the yaw moment; for the target longitudinal torque, the efficiency diagram or load capacity of the main motor on the first axis and the dual motors on the second axis can be comprehensively considered for dynamic allocation, and this embodiment of the invention does not impose any limitations on this. This allocation process ensures the decoupling of yaw control and longitudinal control, improving the system's response speed and accuracy.

[0035] Step 120: Combine the first and second distribution torques of the drive motor to determine the target torque of the drive motor.

[0036] For example, after determining the first and second allocated torques for each drive motor (including the main motor on the first shaft, the left wheel motor on the second shaft, and the right wheel motor), the torque distribution device merges the first and second allocated torques for each drive motor to determine the final target torque for each drive motor. Finally, the target torque is sent as a control command to each motor controller, and the drive motor executes the corresponding torque output.

[0037] In one example, the fusion process can be a weighted summation process, which refers to performing a weighted summation calculation based on the weight coefficients corresponding to the first and second allocated torques, respectively. For example, the formula can be expressed as: Target torque = α × First allocated torque + β × Second allocated torque, where α and β are the weight coefficients corresponding to the first and second allocated torques, respectively, and α + β = 1 (or other normalized form).

[0038] Optionally, the weighting coefficient can be a pre-set fixed value, which the torque distribution device directly calls during calculation. Alternatively, the weighting coefficient can be dynamically adjusted based on the vehicle's real-time status (such as vehicle speed, yaw rate, road surface adhesion coefficient, etc.). For example, at high speeds, yaw stability is prioritized, resulting in a larger α value; during straight-line acceleration, longitudinal performance is prioritized, resulting in a larger β value. Furthermore, α can be adjusted by monitoring the vehicle's yaw error (the difference between the actual yaw rate and the desired yaw rate). If the yaw error is large, α is increased to enhance yaw control; similarly, β can be adjusted by monitoring the longitudinal acceleration error. This embodiment of the invention does not impose limitations.

[0039] In this embodiment, the yaw stability requirements and longitudinal driving requirements of the vehicle are first decoupled. Then, through a dynamically weighted fusion mechanism, the yaw control and longitudinal requirements can be adaptively balanced. This allows the torque control system to respond quickly to emergency control commands while also considering cruising efficiency and smoothness. This collaborative control scheme fully leverages the architectural advantages of single-motor centralized drive and dual-motor distributed drive, comprehensively improving vehicle safety, handling, and comfort while effectively optimizing system load distribution and energy efficiency. It enhances the adaptability and reliability of the drive system under all operating conditions, achieving overall optimization of vehicle dynamic performance and effectively improving the rationality of torque distribution. Furthermore, this invention uses the desired yaw moment determined based on the road surface adhesion coefficient, thereby ensuring the adaptability of the control strategy to actual road conditions, enhancing the control reliability of the vehicle on low-adhesion roads, and reducing the risk of sideslip.

[0040] Figure 2A flowchart of another embodiment of the torque distribution method for a distributed drive system provided by this invention is shown. This method can be executed by a torque distribution device. In this embodiment, the distributed drive system includes a first axle and a second axle. The first axle uses a single-motor centralized drive (i.e., one main motor drives the entire axle), and the second axle uses a dual-motor distributed drive (i.e., a left wheel motor and a right wheel motor drive the left and right wheels respectively). The first axle can be a front axle or a rear axle, and correspondingly, the second axle can be a rear axle or a front axle. Figure 1 Based on the illustrated embodiments, as Figure 2 As shown, the torque distribution method for a distributed drive system provided in this embodiment may include the following steps:

[0041] Step 210: Obtain the desired yaw moment and target longitudinal torque of the vehicle.

[0042] Among them, the expected yaw moment represents the yaw moment that the user expects, determined based on the current road surface adhesion coefficient, and the longitudinal target torque represents the driving torque that the user expects.

[0043] For example, when performing torque distribution, if the vehicle's desired yaw moment and longitudinal target torque are not obtained in advance, the torque distribution device needs to obtain the vehicle's desired yaw moment M_Des and longitudinal target torque Tq_Dmd before performing torque distribution. Specifically, when obtaining the longitudinal target torque, the vehicle speed and accelerator pedal opening can be obtained first, and then a pre-calibrated mapping relationship can be looked up based on the vehicle speed and accelerator pedal opening to obtain the user's desired driving torque, i.e., the longitudinal target torque.

[0044] Optionally, in one possible embodiment, obtaining the desired yaw moment of the vehicle may include:

[0045] S01. Obtain the vehicle's steering wheel angle, vehicle speed, current road surface adhesion coefficient, and actual yaw rate;

[0046] S02. Determine the initial yaw rate by referring to the table based on the steering wheel angle and vehicle speed, and adjust the initial yaw rate according to the road surface adhesion coefficient to obtain the desired yaw rate.

[0047] S03. Determine the desired yaw acceleration based on the desired yaw rate and the actual yaw rate.

[0048] S04. Calculate the product of the desired yaw acceleration and the vehicle's moment of inertia about the vertical axis to obtain the feedforward yaw torque.

[0049] S05. Calculate the feedback yaw torque based on the deviation between the desired yaw rate and the actual yaw rate.

[0050] S06. Calculate the sum of the feedforward yaw moment and the feedback yaw moment to obtain the desired yaw moment.

[0051] For example, the torque distribution device can acquire the required real-time parameters through the vehicle's sensor system. For instance, the steering wheel angle is obtained by an angle sensor on the steering column, reflecting the driver's steering intention; the vehicle speed is obtained by wheel speed sensors or a vehicle inertial measurement unit, representing the vehicle's longitudinal driving state; the road adhesion coefficient can be obtained by tire force sensors or an estimation algorithm based on a vehicle dynamics model, characterizing the maximum friction potential between the tires and the road surface; and the actual yaw rate is directly measured by a gyroscope or inertial measurement unit, reflecting the vehicle's actual rotational rate around its vertical axis.

[0052] Then, the torque distribution device uses the steering wheel angle and vehicle speed as the driver's input and determines the initial yaw rate by looking up a table, which is a two-dimensional mapping table established in advance through bench testing or simulation analysis. Subsequently, the initial yaw rate is limited and adjusted based on the road adhesion coefficient. Specifically, this can be achieved by multiplying the initial yaw rate by the road adhesion coefficient and the gravitational acceleration g, and then dividing by the vehicle speed, or by using other limiting functions, to ensure that the final desired yaw rate does not exceed the physical limits provided by the current road conditions. Here, the theoretical yaw rate that matches the driver's intention is quickly obtained through a lookup table method, and then physical feasibility correction is performed in conjunction with the road adhesion coefficient. This ensures that the vehicle's response meets the driver's expectations and prevents vehicle instability caused by excessive yaw rate on low-adhesion roads, significantly improving the system's safety.

[0053] Furthermore, the torque distribution device can calculate the vehicle's desired yaw moment. Specifically, the desired yaw moment includes two parts: feedforward yaw moment and feedback yaw moment. The feedforward yaw moment M_FF = Iz × w_dot; where Iz is the vehicle's moment of inertia about the vertical axis (i.e., the Z-axis), which can be obtained through pre-calibration; w_dot is the desired yaw angular acceleration, which can be calibrated based on the deviation between the desired yaw angular velocity and the actual yaw angular velocity. The larger the deviation, the larger the desired yaw angular acceleration. The feedback yaw moment M_FB is obtained by performing proportional (P), integral (I), and differential (D) calculations on the deviation between the desired and actual yaw angular angular velocities, and then weighted summing the three results. Finally, the feedforward yaw moment and the feedback yaw moment are added together to obtain the final desired yaw moment M_Des = M_FF + M_FB.

[0054] The method for obtaining the desired yaw moment provided in this optional embodiment achieves accurate and rapid calculation of the desired yaw moment through the synergistic effect of multi-parameter sensing, lookup table mapping, feedforward calculation, and closed-loop feedback. This method fully considers actual constraints such as the road surface adhesion coefficient to ensure the physical feasibility of the calculation results; and through a feedforward-feedback composite control architecture, it balances response speed and control accuracy. By accurately calculating the desired yaw moment, it provides an accurate control target for the torque distribution of this invention, laying a solid foundation for improving vehicle handling stability.

[0055] Step 220: Based on the desired yaw moment and longitudinal target torque, perform initial torque distribution to determine the required torque for the left and right wheels of the second axle.

[0056] The left wheel demand torque represents the torque allocated to the left wheel of the second axle that meets the yaw torque range limit of the left wheel, and the right wheel demand torque represents the torque allocated to the right wheel of the second axle that meets the yaw torque range limit of the right wheel.

[0057] For example, when distributing torque, the torque can be distributed to the second axle first, and then balanced between the first and second axles. Specifically, the yaw moment range limitation refers to a predetermined torque safety boundary based on factors such as motor torque output capability, road surface adhesion conditions, and vehicle stability requirements, used to ensure that the distributed torque is within a feasible and safe range. In a specific embodiment, the torque distribution device can use a differential torque distribution strategy to create a torque difference between the left and right wheels, thereby generating the required yaw moment while ensuring that the total torque output meets the longitudinal drive requirements.

[0058] Understandably, by prioritizing torque distribution to the distributed drive shafts, the advantages of independent dual-motor control are fully utilized, enabling the rapid and precise generation of the desired yaw moment. Furthermore, by introducing torque range limitations, the risk of instability due to excessive torque on a single wheel is effectively prevented, thus improving the system's safety and reliability.

[0059] Optionally, in one possible embodiment, based on the desired yaw moment and the target longitudinal torque, an initial torque distribution is performed to determine the required torque for the left and right wheels of the second axle, which may include:

[0060] S1. Based on the vertical load ratio of the first axis and the second axis, the longitudinal target torque is distributed to determine the total required torque of the second axis.

[0061] S2. Distribute the desired yaw moment and the total required torque of the second axle in an average two-way distribution to obtain the required yaw moment of the left wheel and the required yaw moment of the right wheel of the second axle.

[0062] S3. Based on the yaw torque capacity of the left wheel and the yaw torque capacity of the right wheel of the second axle, adjust and compensate the required yaw torque of the left wheel and the required yaw torque of the right wheel to obtain the processed required yaw torque of the left wheel and the processed required yaw torque of the right wheel.

[0063] S4. Perform torque conversion processing on the processed left wheel yaw moment to obtain the left wheel torque requirement, and perform torque conversion processing on the processed right wheel yaw moment to obtain the right wheel torque requirement.

[0064] For example, the vertical load ratio of the first and second axles refers to the proportion of the vehicle's total weight distributed between the first and second axles under the current driving conditions. This parameter can be obtained through suspension displacement sensors or an estimation algorithm based on longitudinal acceleration. The total required torque of the second axle refers to the total torque value allocated to the second axle from the longitudinal target torque according to this vertical load ratio. Specifically, it is calculated as: Total required torque of the second axle Tq_2_1 = Longitudinal target torque Tq_Dmd × Vertical load ratio of the second axle Fz2Ratio. Furthermore, if necessary, the total required torque of the first axle can also be calculated as: Longitudinal target torque Tq_Dmd × Vertical load ratio of the first axle Fz1Ratio. By using a distribution strategy based on the vertical load ratio, the distribution of driving torque is positively correlated with the ground load of each axle, effectively avoiding tire slippage or wasted traction due to improper torque distribution, thus improving the vehicle's power and energy efficiency.

[0065] Once the total required torque Tq_2_1 of the second axle is determined, an average two-distribution strategy can be adopted to initially distribute the desired yaw moment and the total required torque of the second axle between the left and right wheels. Here, the required yaw moment of the left wheel and the required yaw moment of the right wheel represent the torque components generated on the left and right wheels, respectively, to achieve the desired yaw moment and control the total drive torque of the second axle. In specific implementation, this can be calculated using the following formula:

[0066] The yaw moment required by the left wheel of the second axle is M_2L_1=0.5×M_Des-0.5×Tq_ 2_1×w;

[0067] The yaw moment required by the right wheel of the second axle is M_2R_1=0.5×M_Des+0.5×Tq_2_1×w.

[0068] Where w is half of the second axle track. The average two-way distribution strategy provides a clear and concise distribution benchmark, ensuring both the efficiency of yaw moment generation and the balanced output of longitudinal driving force, laying a reasonable foundation for subsequent optimization and adjustment.

[0069] Furthermore, the initially allocated yaw torque requirements for the left and right wheels of the second axle must also be within the yaw torque capabilities of the left and right wheels of the second axle. Here, yaw torque capability refers to the range of yaw torque that each wheel can provide under the current condition. This range may be limited by factors such as motor peak torque, road surface adhesion coefficient, and vertical load, but this embodiment of the invention does not impose such limitations. During the adjustment process, it is first determined whether the initial required yaw torque for the left and right wheels exceeds their yaw torque capabilities. If it exceeds the limit, then restrictions and mutual compensation are applied between the left and right wheels of the second axle to ensure that, within the yaw torque capabilities of the left and right wheels of the second axle, the sum of the processed required yaw torque for the left and right wheels is as equal to or as close as possible to the desired yaw torque M_Des. The processed required yaw torque for the left wheel of the second axle obtained in this step can be denoted as M_2L_2, and the processed required yaw torque for the right wheel can be denoted as M_2R_2.

[0070] By employing an adjustment and compensation mechanism based on actual capabilities, the physical feasibility of torque distribution is ensured, preventing torque saturation or adhesion failure in individual wheels. At the same time, coordinated distribution maintains the overall yaw control effect, improving the robustness and control efficiency of the system.

[0071] Finally, the processed yaw moment requirements of the left and right wheels need to be converted into torques to obtain the required torques for the left and right wheels. Specifically, the required torque for the left wheel can be obtained by dividing the processed yaw moment requirement of the left wheel by half the track width of the left wheel and then multiplying it by the tire rolling radius, which can be denoted as Tq_2L_1; the required torque for the right wheel can be obtained by dividing the processed yaw moment requirement of the right wheel by half the track width of the right wheel and then multiplying it by the tire rolling radius, which can be denoted as Tq_2R_1. At this point, if the adjusted total required torque for the second axle is denoted as Tq_2_2, then Tq_2_2 = Tq_2L_1 + Tq_2R_1.

[0072] The optional embodiment provides a torque initial distribution method for the second axle, which achieves a reasonable distribution of the desired yaw moment and longitudinal target torque between the left and right wheels of the second axle through four key steps: load proportional distribution, average binary distribution, capacity constraint adjustment, and torque conversion. This method fully considers the actual load distribution of the vehicle and the torque capacity limitations of each wheel, ensuring the physical feasibility and control effectiveness of the distribution scheme. It guarantees both the accuracy of vehicle yaw stability control and optimizes the distribution efficiency of longitudinal driving force, providing a reliable guarantee for improving the overall performance of the vehicle.

[0073] Step 230: Determine the initial torque distribution for the first axle based on the longitudinal target torque, the required torque for the left wheel of the second axle, and the required torque for the right wheel.

[0074] The initial allocated torque of the first shaft represents the torque initially allocated to the main motor of the first shaft.

[0075] For example, after completing the torque distribution on the second shaft, the initial distributed torque on the first shaft can be calculated. The initial distributed torque on the first shaft refers to the torque value initially allocated to the main motor on the first shaft. Its calculation can be based on the longitudinal target torque minus the sum of the required torques of the left and right wheels already allocated to the second shaft. That is, if the initial distributed torque on the first shaft is denoted as Tq_1_1, then Tq_1_1 = Tq_Dmd - Tq_2_2.

[0076] This coordinated front and rear axle distribution strategy achieves a reasonable distribution of driving torque, which not only meets the overall driving needs of the vehicle but also optimizes the load utilization of the front and rear axles, ensuring that the total driving torque of the vehicle matches the longitudinal needs of the driver, while making full use of the driving capabilities of the front and rear axles.

[0077] Step 240: Determine the first and second distribution torques of each drive motor based on the initial distribution torque of the first shaft, the required torque of the left wheel of the second shaft, and the required torque of the right wheel.

[0078] For example, after the initial torque distribution described above is completed, the torque distribution can be further refined to determine two-dimensional torque components for each drive motor. That is, it is necessary to determine the first and second distributed torques for the main motor of the first shaft, the left wheel motor and the right wheel motor of the second shaft, respectively, in order to meet the torque limit requirements and the driver's driving posture requirements as much as possible.

[0079] Optionally, in one possible embodiment, determining the first and second distribution torques of each drive motor based on the initial distribution torque of the first shaft, the left wheel demand torque of the second shaft, and the right wheel demand torque may include:

[0080] S10. Determine the required torque of the first shaft motor based on the initial allocated torque of the first shaft and the torque limit range of the main motor of the first shaft; wherein, the required torque of the first shaft motor must be within the torque limit range of the main motor of the first shaft.

[0081] S20. Calculate the sum of the motor torque required by the first shaft, the left wheel torque required by the second shaft, and the right wheel torque required by the second shaft to obtain the first total torque.

[0082] S30. If it is determined that the first total torque is within the total range of motor torque limits, then the motor demand torque of the first shaft is determined as the first allocated torque of the main motor of the first shaft, the left wheel demand torque of the second shaft is determined as the first allocated torque of the left wheel motor of the second shaft, and the right wheel demand torque of the second shaft is determined as the first allocated torque of the right wheel motor of the second shaft.

[0083] S40. Calculate the sum of the first distributed torque of the main motor of the first shaft, the first distributed torque of the left wheel motor of the second shaft, and the first distributed torque of the right wheel motor of the second shaft to obtain the second total torque.

[0084] S50. If the second total torque is determined to be equal to the longitudinal target torque, then the first distribution torque of the main motor of the first shaft is determined as the second distribution torque of the main motor of the first shaft, the first distribution torque of the left wheel motor of the second shaft is determined as the second distribution torque of the left wheel motor of the second shaft, and the first distribution torque of the right wheel motor of the second shaft is determined as the second distribution torque of the right wheel motor of the second shaft.

[0085] For example, the initial allocated torque Tq_1_1 of the first shaft obtained based on step 230 above should meet the torque limit of the main motor of the first shaft. The torque limit range of the main motor of the first shaft refers to the range of torque that the main motor can stably output under the current operating conditions. This range is jointly determined by motor characteristics (such as peak torque, continuous operating torque, etc.), temperature conditions, and the energy management system, and is not limited in this embodiment of the invention. The required torque of the motor of the first shaft is a feasible torque value obtained by limiting the initial allocated torque within this torque limit range, which can be denoted as Tq_1_2. In specific implementation, if the initial allocated torque Tq_1_1 of the first shaft exceeds the upper limit, then Tq_1_2 takes the upper limit value; if it is lower than the lower limit, then the lower limit value is taken; otherwise, the original value is maintained. By making feasible corrections to the initial allocated torque of the first shaft, it can be ensured that the torque requirement of the main motor of the first shaft is within its safe operating range, effectively preventing risks such as motor overload and overheating, and improving the reliability and durability of the system.

[0086] Understandably, the sum of the motor demand torque Tq_1_2 of the first axis and the adjusted total demand torque Tq_2_2 of the second axis (i.e., the first total torque) obtained above may exceed the total range of motor torque limits. Furthermore, the total torque after the torque limit of the first axis may also exceed the longitudinal target torque. Therefore, it is necessary to limit and compensate for Tq_1_2 and Tq_2_2 based on the maximum / minimum torque limits of the main motor of the first axis (i.e., the torque limit range of the main motor of the first axis), the maximum / minimum torque limits of the left wheel motor of the second axis (i.e., the torque limit range of the left wheel motor of the second axis), and the maximum / minimum torque limits of the right wheel motor of the second axis (i.e., the torque limit range of the right wheel motor of the second axis).

[0087] The total torque limit range refers to the total torque range that the distributed drive system can provide in the current state. This range is formed by the superposition of the torque limit ranges of each motor, with an upper limit of min(TqLmtMax + LTqLmtMax + RTqLmtMax, Tq_Dmd) and a lower limit of (TqLmtMin + LTqLmtMin + RTqLmtMin). TqLmtMax, LTqLmtMax, and RTqLmtMax are the maximum torque limits of the main motor on the first axis, the left wheel motor on the second axis, and the right wheel motor on the second axis, respectively. TqLmtMin, LTqLmtMin, and RTqLmtMin are the minimum torque limits of the main motor on the first axis, the left wheel motor on the second axis, and the right wheel motor on the second axis, respectively.

[0088] When the first total torque is within the total range of motor torque limits, it indicates that the current torque distribution scheme is feasible at the system level. At this time, the required torque of each drive motor can be directly determined as its first allocated torque. That is, the required torque Tq_1_2 of the first shaft motor is determined as the first allocated torque Tq_1_3 of the main motor of the first shaft, the required torque Tq_2L_1 of the left wheel of the second shaft is determined as the first allocated torque Tq_2L_2 of the left wheel motor of the second shaft, and the required torque Tq_2R_1 of the right wheel of the second shaft is determined as the first allocated torque Tq_2R_2 of the right wheel motor of the second shaft.

[0089] Furthermore, the sum of the first distributed torques of each drive motor can be calculated to obtain the second total torque = Tq_1_3 + Tq_2L_2 + Tq_2R_2. The second total torque represents the sum of the torques required by the three drive motors to achieve yaw stability control. When the second total torque is equal to the longitudinal target torque, it indicates that the current yaw control torque distribution simultaneously meets the longitudinal driving requirements. At this time, the first distributed torque of each motor is directly determined as its second distributed torque, achieving a set of torques that simultaneously meets dual control objectives. Specifically, if the second distributed torque of the main motor of the first axle is denoted as Tq_1_4, the second distributed torque of the left wheel motor of the second axle is denoted as Tq_2L_3, and the second distributed torque of the right wheel motor of the second axle is denoted as Tq_2R_3, then Tq_1_4 = Tq_1_3, Tq_2L_3 = Tq_2L_2, and Tq_2R_3 = Tq_2R_2.

[0090] This optional embodiment achieves optimized determination of torque distribution for each drive motor through a hierarchical torque distribution verification mechanism. This method ensures the feasibility and optimality of the torque distribution scheme by constraining the torque capacity of individual motors, verifying the feasibility of the total motor torque, and coordinating the yaw and longitudinal control objectives. This systematic distribution strategy not only guarantees the precise implementation of vehicle yaw stability control but also optimizes the rational distribution of longitudinal driving force, providing technical support for improving the overall performance of the vehicle.

[0091] Optionally, in one possible embodiment, based on the above embodiments, it is also possible that the first total torque exceeds the total range of motor torque limits. In this case, the method provided by the embodiments of the present invention may further include:

[0092] S31. If it is determined that the first total torque exceeds the total range of motor torque limits, then calculate the first torque difference value that exceeds the total range of motor torque limits.

[0093] S32. Adjust the motor demand torque of the first shaft according to the first torque difference, and determine the adjusted motor demand torque of the first shaft as the first allocated torque of the main motor of the first shaft; wherein, the adjusted motor demand torque of the first shaft is located within the torque limit range of the main motor of the first shaft.

[0094] S33. If it is determined that the first torque difference is entirely used to adjust the motor torque required by the first shaft, then the left wheel torque required by the second shaft is determined as the first distributed torque of the left wheel motor of the second shaft, and the right wheel torque required by the second shaft is determined as the first distributed torque of the right wheel motor of the second shaft.

[0095] S34. If it is determined that the first torque difference is only partially used to adjust the motor torque demand of the first shaft, then the first residual torque difference is determined, and the left wheel torque demand and right wheel torque demand of the second shaft are adjusted by an equal amount according to the first residual torque difference. The adjusted left wheel torque demand is determined as the first distribution torque of the left wheel motor of the second shaft, and the adjusted right wheel torque demand is determined as the first distribution torque of the right wheel motor of the second shaft. Wherein, the adjusted left wheel torque demand is located within the torque limit range of the left wheel motor of the second shaft, and the adjusted right wheel torque demand is located within the torque limit range of the right wheel motor of the second shaft.

[0096] For example, when it is determined that the first total torque exceeds the total range of motor torque limits, it is necessary to adjust and compensate for the motor torque requirements of the first shaft, the left wheel torque requirements of the second shaft, and the right wheel torque requirements in order to determine the first allocated torque of each drive motor. Specifically, the first torque difference exceeding the total range of motor torque limits is first calculated, that is, the portion of the first total torque exceeding the upper or lower limit of the total range of motor torque limits is determined, and then adjustments and compensations are made.

[0097] During adjustment and compensation, the excess torque is prioritized by changing the torque requirement of the first axle motor. The remaining portion, which cannot be satisfied by the adjusted first axle motor torque, is then addressed by changing the torque requirement of the second axle. This approach aims to minimize changes to the torque distribution of the rear axle, thereby ensuring that the yaw moment generated by the rear axle remains unaffected. The adjusted first axle motor torque requirement must be within the torque limit range of the first axle's main motor. For the torque requiring compensation by the second axle (denoted as ΔTq1), it is preferentially distributed evenly to the left and right wheels of the second axle for compensation, i.e., each wheel is reduced by 0.5 × ΔTq1. This even compensation satisfies the torque limit while maintaining the sum of the yaw moments of the left and right wheels of the second axle. If this compensation scheme exceeds the torque limits of the left and right rear axles, the compensation continues within the torque capacity range of the left and right wheels. In other words, the adjusted left wheel torque requirement must be within the torque limit range of the left wheel motor of the second axle, and the adjusted right wheel torque requirement must be within the torque limit range of the right wheel motor of the second axle.

[0098] This optional embodiment provides comprehensive torque safety assurance for the distributed drive system by establishing a graded and coordinated torque over-limit adjustment mechanism. Following an adjustment sequence of "single-axis priority, dual-axis coordination," this method maximizes the vehicle's yaw stability control capability while ensuring the total system torque does not exceed limits. This significantly enhances the drive system's adaptability and safety under extreme conditions, providing reliable technical support for overall vehicle performance.

[0099] Optionally, in one possible embodiment, based on the above embodiments, it is possible that due to adjustments and compensations made to the motor torque requirement of the first shaft, the left wheel torque requirement, and the right wheel torque requirement of the second shaft, a mismatch may occur between the aforementioned second total torque and the longitudinal target torque. In this case, the method provided by the embodiments of the present invention may further include:

[0100] S51. If it is determined that the second total torque is not equal to the longitudinal target torque, then calculate the second torque difference between the second total torque and the longitudinal target torque.

[0101] S52. Adjust the first distribution torque of the main motor of the first shaft according to the second torque difference, and determine the adjusted first distribution torque of the main motor of the first shaft as the second distribution torque of the main motor of the first shaft; wherein, the adjusted first distribution torque of the main motor of the first shaft is located within the torque limit range of the main motor of the first shaft.

[0102] S53. If it is determined that the second torque difference is entirely used to adjust the first distribution torque of the main motor of the first shaft, then the first distribution torque of the left wheel motor of the second shaft is determined as the second distribution torque of the left wheel motor of the second shaft, and the first distribution torque of the right wheel motor of the second shaft is determined as the second distribution torque of the right wheel motor of the second shaft.

[0103] S54. If it is determined that the second torque difference is only partially used to adjust the first distribution torque of the main motor of the first shaft, then the second residual torque difference is determined, and the first distribution torque of the left wheel motor of the second shaft and the first distribution torque of the right wheel motor of the second shaft are adjusted by the same amount according to the second residual torque difference. The adjusted first distribution torque of the left wheel motor of the second shaft is determined as the second distribution torque of the left wheel motor of the second shaft, and the adjusted first distribution torque of the right wheel motor of the second shaft is determined as the second distribution torque of the right wheel motor of the second shaft.

[0104] Specifically, the first distributed torque of the adjusted left wheel motor of the second axle is located within the torque limit range of the left wheel motor of the second axle, and the first distributed torque of the adjusted right wheel motor of the second axle is located within the torque limit range of the right wheel motor of the second axle.

[0105] For example, based on the optimal torque distribution to satisfy the desired yaw moment (the first distributed torque Tq_1_3 of the main motor on the first shaft, the first distributed torque Tq_2L_2 of the left wheel motor on the second shaft, and the first distributed torque Tq_2R_2 of the right wheel motor on the second shaft), due to the above adjustments and compensations, the second total torque may not be equal to the target longitudinal torque. In this case, the difference between the second total torque and the target longitudinal torque can be calculated to obtain the second torque difference. Similarly, the adjustment principle is to prioritize compensating for all or part of the second torque difference through the main motor on the first shaft. The first distributed torque of the main motor on the first shaft after adjustment must still be within the torque limit range of the main motor on the first shaft. In specific implementation, if the compensated torque is still within the torque limit range, a full compensation strategy is adopted; otherwise, compensation is made to the boundary value of the range. When the main motor on the first shaft can independently undertake the compensation task of the entire second torque difference, the torque distribution of the left and right wheel motors on the second shaft remains unchanged, and their first distributed torques are directly determined as the second distributed torque. If the main motor of the first shaft cannot independently handle the compensation of the entire second torque difference, then the portion that the first shaft cannot compensate for is allocated to the second shaft. Specifically, the remaining portion of the second torque difference that was not absorbed by the first shaft compensation can be evenly distributed to the torques of the left and right wheel motors of the second shaft, that is, the first allocated torque of each left and right wheel is increased by half of the second remaining torque difference, while ensuring that the adjusted torque is still within its respective torque limit range. Based on the above adjustment and compensation, the optimal allocated torque to achieve the longitudinal target torque Tq_Dmd can be obtained, which also determines the second allocated torque of each drive motor in the scenario of this optional embodiment.

[0106] This optional embodiment improves the torque distribution function of the distributed drive system by establishing a hierarchical and collaborative longitudinal torque compensation mechanism. While ensuring the accurate realization of longitudinal driving requirements, it maximizes the yaw stability control effect of the vehicle, significantly enhances the adaptability and control accuracy of the drive system under various operating conditions, and provides a reliable technical guarantee for the overall performance optimization of the vehicle.

[0107] Step 250: Determine the first weighting coefficient and the second weighting coefficient.

[0108] Wherein, the first weighting coefficient is the weighting coefficient corresponding to the first allocated torque, and the second weighting coefficient is the weighting coefficient corresponding to the second allocated torque.

[0109] For example, the first weighting coefficient is the weight of the first distributed torque (yaw control torque) in the final torque, which can be denoted as fac, 0≤fac≤1; the second weighting coefficient is the weight of the second distributed torque (longitudinal drive torque) in the final torque, which can be denoted as (1-fac). The first and second weighting coefficients can be preset fixed values, or they can be dynamically adjusted according to the real-time vehicle status such as vehicle speed, yaw rate, road adhesion coefficient, etc. The embodiments of the present invention do not impose any limitations.

[0110] Optionally, in one possible embodiment, determining the first weighting coefficient and the second weighting coefficient may include:

[0111] S100, calculate the first deviation between the longitudinal target torque and the sum of the first distributed torques of each drive motor, and calculate the second deviation between the vehicle's expected yaw rate and the actual yaw rate.

[0112] S200. Based on the first deviation and the second deviation, determine the first weighting coefficient and the second weighting coefficient; wherein the first weighting coefficient is positively correlated with the second deviation and negatively correlated with the first deviation.

[0113] For example, the first deviation ΔTq = [Tq_Dmd - (Tq_1_3 + Tq_2L_2 + Tq_2R_2)] reflects the degree to which the current yaw control torque distribution meets the longitudinal drive requirements. The second deviation YawRateErr = desired yaw rate - actual yaw rate reflects the accuracy of the current vehicle yaw stability control. A larger absolute value of the second deviation YawRateErr indicates that more yaw torque requirements should be met to suppress the yaw torque deviation, resulting in a larger fac. Conversely, a larger first deviation ΔTq indicates a larger longitudinal torque deviation, requiring more longitudinal torque requirements to reduce the longitudinal torque deviation, resulting in a smaller fac.

[0114] In practical implementation, a nonlinear mapping relationship based on fuzzy logic or lookup table method can be adopted: when the second deviation increases, the first weighting coefficient is increased to strengthen yaw stability control; when the first deviation increases, the first weighting coefficient is decreased to take into account the longitudinal drive requirements. The second weighting coefficient is then adjusted accordingly to ensure that the sum of the first and second weighting coefficients is 1.

[0115] This optional embodiment achieves intelligent and adaptive torque distribution strategy through a dual-bias feedback weight adjustment mechanism. By dynamically adjusting the weight distribution of the two control objectives based on the actual conditions of longitudinal drive and yaw stability, it ensures both vehicle stability under extreme conditions and driving performance during normal driving. This multi-objective optimization-based weight determination strategy significantly improves the adaptability and overall performance of the distributed drive system under different operating conditions.

[0116] Step 260: Based on the first weighting coefficient and the second weighting coefficient, the first allocated torque and the second allocated torque of the drive motor are weighted and summed to obtain the target torque of the drive motor.

[0117] For example, by weighted fusion of the two torque components of each drive motor, the final target torque can be obtained. This target torque is sent as a control command to each motor controller to achieve precise torque output control. The specific calculation formula is as follows:

[0118] The target torque of the main motor of the first shaft is Tq_1 = Tq_1_3×fac + Tq_1_4×(1-fac);

[0119] The target torque of the left wheel motor of the second shaft is Tq_2L = Tq_2L_2×fac + Tq_2L_3×(1-fac);

[0120] The target torque of the right wheel motor of the second shaft is Tq_2R = Tq_2R_2×fac + Tq_2R_3×(1-fac).

[0121] This weighted fusion strategy ensures both the vehicle's basic driving needs and stability under extreme conditions such as high-speed cornering. It achieves an optimal balance between yaw stability and longitudinal drive, enabling the vehicle to obtain the best overall performance under various conditions and significantly improving the vehicle's active safety and driving quality.

[0122] In this embodiment, the advantages of the hybrid drive architecture are fully utilized through a multi-stage allocation and adaptive fusion strategy, significantly improving the rationality of torque distribution. On the one hand, the coordinated allocation between the front and rear axles and the differential control of the left and right wheels achieves unified optimization of yaw stability and longitudinal driving performance. On the other hand, the dynamic adjustment of the weighting coefficients ensures the system's adaptability to different driving conditions. Ultimately, while comprehensively improving vehicle handling stability, safety, and driving efficiency, the adaptability and reliability of the drive system under various road conditions and driving scenarios are enhanced.

[0123] For example, Figure 3 A flowchart of yet another embodiment of the torque distribution method for a distributed drive system provided by this invention is shown. This method can be executed by a torque distribution device. The distributed drive system in this embodiment is described in detail using an example where the first axle is the front axle and the second axle is the rear axle. Figure 3 As shown, the torque distribution method provided in this embodiment may include the following steps:

[0124] (1) Calculate the desired vehicle yaw rate w_Des (also known as the aforementioned desired yaw rate) based on the steering wheel angle, vehicle speed, and road surface adhesion coefficient.

[0125] For example, using the steering wheel and vehicle speed as two dimensions as driver intention input, the driver's expected yaw rate is calibrated. Considering that the lateral force on a low-adhesion road surface cannot be as large as that on a high-adhesion road surface, a low-adhesion driver's expected yaw rate is calibrated separately on a low-adhesion road surface using the steering wheel and vehicle speed, based on the road adhesion coefficient. Under the same working conditions, the expected yaw rate on a low-adhesion road surface is smaller than that on a high-adhesion road surface.

[0126] (2) Calculate the desired additional yaw moment M_Des (i.e. the aforementioned desired yaw moment), which includes the feedforward yaw moment and the feedback yaw moment.

[0127] The feedforward yaw moment M_FF = Iz × w_dot, where w_dot is the desired yaw acceleration, which can be calibrated based on the deviation between the desired and actual yaw angular velocities. A larger deviation in yaw velocity results in a larger desired yaw acceleration. The feedback yaw moment M_FB is adjusted using PID control based on the yaw velocity deviation. The desired additional yaw moment for the vehicle is M_Des = M_FF + M_FB.

[0128] Then, the torque distribution is performed on the front axle, left rear axle, and right rear axle:

[0129] (3) Pre-allocate the required torque of the front axle and the required torque of the rear axle according to the ratio of the vertical loads of the front and rear axles.

[0130] Specifically, the longitudinal target torque is obtained, and the longitudinal target torque is distributed to the front and rear axles according to the ratio of the vertical loads on the front and rear axles, i.e., Tq_Fr_1 = Tq_Dmd × FzFrntRatio, Tq_Re_1 = Tq_Dmd × FzReRatio, where Tq_Fr_1 and Tq_Re_1 are the initially allocated required torques for the front and rear axles, respectively, Tq_Dmd is the longitudinal target torque, and FzFrntRatio and FzReRatio are the ratios of the vertical loads on the front and rear axles to the total mass of the vehicle, respectively.

[0131] (4) Distribute the yaw moment of the left and right rear axles according to the pre-allocated rear axle required torque and the expected yaw moment.

[0132] The initial torque distribution between the left and right rear axles aims to simultaneously satisfy the required rear axle torque Tq_Re_1 and the desired yaw moment M_Des. Specifically: M_RL_1 = 0.5 × M_Des - 0.5 × Tq_Re_1 × w, M_RR_1 = 0.5 × M_Des + 0.5 × Tq_Re_1 × w. Here, M_RL_1 is the initially distributed yaw moment for the left rear axle, M_RR_1 is the initially distributed yaw moment for the right rear axle, and w is half the rear axle track width.

[0133] (5) Calculate the yaw torque capacity of the left and right rear axles.

[0134] (6) Limit and compensate the yaw moments of the left and right rear axles within their respective capabilities. The goal is to make the sum of the yaw moments of the left and right rear axles satisfy M_des as much as possible within their capabilities.

[0135] For example, the yaw moment of the initially allocated left and right rear axles needs to be within the yaw moment capability of the left and right rear axles. If it exceeds the limit, then the left and right rear axles need to be restricted and compensated for each other. The purpose is to make the sum of the left rear yaw moment and the right rear yaw moment as equal to or close to M_Des as possible within the yaw moment capability of the left and right rear axles. The left and right rear yaw moments obtained in this step are denoted as M_RL_2 and M_RR_2.

[0136] (7) Calculate the required torque of the left and right rear axles based on the yaw moment of the allocated left and right rear axles. Then the required torque of the front axle = longitudinal target torque - (required torque of the left rear axle + required torque of the right rear axle).

[0137] This step calculates the initial front axle torque requirement. The calculated yaw moments of the left and right rear axles are then converted into corresponding left and right rear axle torque requirements, denoted as Tq_RL_1 and Tq_RR_1. At this point, the rear axle torque requirement is Tq_Re_2 = Tq_RL_1 + Tq_RR_1, and the front axle torque requirement is Tq_Fr_2 = Tq_Dmd - Tq_Re_2.

[0138] (8) Based on the limitations of the front axle torque capacity, the left rear axle torque capacity and the right rear axle torque capacity, the front axle torque demand, the left rear axle torque demand and the right rear axle torque demand are limited and compensated to obtain new front axle torque demand, left rear axle torque demand and right rear axle torque demand. This allocated torque is the optimal allocated torque to achieve the vehicle yaw moment.

[0139] For example, the sum of the required torque Tq_Fr_2 for the front axle and the required torque Tq_Re_2 for the rear axle obtained above may exceed the motor torque limit. Even after the front axle torque limit, the sum may still exceed the longitudinal target torque. Therefore, it is necessary to limit and compensate for Tq_Fr_2 and Tq_Re_2 according to the maximum / minimum torque limits of the front motor, the left rear motor, and the right rear motor. The upper limit of the sum of Tq_Fr_2 + Tq_Re_2 is min(FrTqLmtMax + RLTqLmtMax + RRTqLmtMax, Tq_Dmd), and the lower limit is FrTqLmtMin + RLTqLmtMin + RRTqLmtMin. Among them, FrTqLmtMax, RLTqLmtMax, and RRTqLmtMax are the maximum torque limits for the front axle motor, the left rear motor, and the right rear motor, respectively; FrTqLmtMin, RLTqLmtMin, and RRTqLmtMin are the minimum torque limits for the front axle motor, the left rear motor, and the right rear motor, respectively.

[0140] The limitation and compensation scheme consists of two steps: 1) For the portion where the sum of Tq_Fr_2 + Tq_Re_2 exceeds the upper or lower limit, the excess portion is first satisfied by changing the torque demand of the front axle. The remaining portion that cannot be satisfied by the front axle torque is then satisfied by changing the torque demand of the rear axle. The purpose of this is to minimize the change in the torque distribution of the rear axle, thereby ensuring that the yaw moment generated by the rear axle is not affected; 2) For the torque that needs to be compensated by the rear axle (denoted as ΔTq1), it is first distributed evenly to the left and right rear axles for compensation, that is, each is reduced by 0.5×ΔTq1. The advantage of this average compensation is that it satisfies the torque limit while keeping the sum of the yaw moments of the left and right rear axles unchanged. If this compensation scheme exceeds the torque limit of the left and right rear axles, the transfer and compensation will continue within the torque capacity range of the left and right rear axles. The required torque for the front axle, left rear axle, and right rear axle obtained in this step are the optimal front axle, left rear axle, and right rear axle torque distributions to achieve the desired yaw moment M_Des, denoted as Tq_Fr_3, Tq_RL_2, and Tq_RR_2.

[0141] (9) To satisfy the longitudinal target torque, based on the optimal distribution torque to satisfy the desired yaw moment, compare the sum of the required torques of the front axle, left rear axle, and right rear axle with the longitudinal target torque, and redistribute the torque to satisfy the longitudinal target torque. This redistributed torque is the optimal distribution torque to achieve the longitudinal target torque.

[0142] For example, based on the optimal torque distribution (Tq_Fr_3, Tq_RL_2, and Tq_RR_2) to satisfy the desired yaw moment, the deviation between the sum of the required torques of the front axle, left rear axle, and right rear axle and the longitudinal target torque is compared. If there is a deviation (denoted as ΔTq2), the torque needs to be redistributed. ΔTq2 is preferentially allocated to the front axle. If the torque limit of the front axle is exceeded after allocating ΔTq2, the portion that the front axle cannot compensate for is redistributed to the rear axle. At this time, the torque compensation scheme of the left and right rear axles is the same as the scheme provided in step (8). The required torques of the front axle, left rear axle, and right rear axle obtained in this step are the optimal torque distribution of the front axle, left rear axle, and right rear axle to achieve the longitudinal target torque Tq_Dmd, denoted as Tq_Fr_4, Tq_RL_3, and Tq_RR_3.

[0143] (10) The optimal distribution torque for achieving the vehicle yaw moment and the optimal distribution torque for achieving the longitudinal target torque are weighted and summed to obtain the final distribution torque.

[0144] For example, the torque distribution to achieve the desired yaw moment may not achieve the target longitudinal torque, and similarly, the torque distribution to achieve the target longitudinal torque may not achieve the desired yaw moment. Therefore, it is necessary to combine these two torque distributions based on the vehicle's operating conditions to obtain the final torque distribution. The final distributed torque is the weighted sum of the two. That is:

[0145] The final distributed torque of the front axle main motor is Tq_Fr = Tq_Fr_3×fac + Tq_Fr_4×(1-fac);

[0146] The final torque distribution of the rear axle left wheel motor is Tq_RL = Tq_RL_2×fac + Tq_RL_3×(1-fac);

[0147] The final distributed torque of the rear axle right wheel motor is Tq_RR = Tq_RR_2×fac + Tq_RR_3×(1-fac).

[0148] Where fac is the weighting coefficient of the distributed torque for achieving the desired vehicle yaw moment in the final distributed torque, 0≤fac≤1, then (1-fac) is the weighting coefficient of the distributed torque for achieving the longitudinal target torque in the final distributed torque. Understandably, fac is influenced by two factors: the deviation ΔTq = [Tq_Dmd - (Tq_Fr_3 + Tq_RL_2 + Tq_RR_2)] between the longitudinal target torque and the distributed torque for achieving the desired vehicle yaw moment, and the deviation YawRateErr between the desired yaw rate and the actual yaw rate. The larger the absolute value of YawRateErr, the more the yaw moment requirement should be met to suppress the yaw moment deviation, thus resulting in a larger fac; the larger ΔTq indicates a larger longitudinal torque deviation, thus requiring more longitudinal torque to be met to reduce the longitudinal torque deviation, resulting in a smaller fac.

[0149] In this embodiment, based on the optimal torque distribution scheme to achieve the desired yaw moment, and under the premise of not exceeding the system torque limit and not exceeding the longitudinal target torque, the optimal torque distribution for the front axle, left rear axle, and right rear axle is obtained. Based on this torque distribution, a further optimal torque distribution scheme to achieve the longitudinal target torque is developed. Then, based on the vehicle's two control objectives (yaw rate and longitudinal target torque), these two distribution schemes are weighted and summed. This distribution strategy yields the optimal torque distribution that balances these two vehicle control objectives under various operating conditions. This application achieves overall optimization of vehicle dynamic performance and effectively improves the rationality of torque distribution.

[0150] Figure 4A schematic diagram of an embodiment of the torque distribution device for a distributed drive system provided by this invention is shown. In this distributed drive system, the first shaft uses a single-motor centralized drive, and the second shaft uses a dual-motor distributed drive. The first shaft can be a front axle or a rear axle. Figure 4 As shown, the device 40 includes: a first processing unit 401 and a second processing unit 402.

[0151] The first processing unit 401 is used to perform torque distribution processing based on the vehicle's expected yaw moment and longitudinal target torque, and to determine the first distribution torque and the second distribution torque of each drive motor.

[0152] Among them, the expected yaw moment represents the yaw moment determined by the user based on the current road surface adhesion coefficient, and the longitudinal target torque represents the driving torque expected by the user; the drive motor includes the main motor of the first shaft, the left wheel motor and the right wheel motor of the second shaft; the first allocated torque represents the torque allocated to achieve the expected yaw moment, and the second allocated torque represents the torque allocated to achieve the longitudinal target torque;

[0153] The second processing unit 402 is used to perform fusion processing on the first and second allocated torques of the drive motor to determine the target torque of the drive motor.

[0154] In one alternative embodiment, the first processing unit 401 is specifically used for:

[0155] Based on the desired yaw moment and the target longitudinal torque, an initial torque distribution is performed to determine the required torque for the left wheel and the required torque for the right wheel of the second axle. The required torque for the left wheel represents the torque allocated to the left wheel of the second axle that meets the yaw moment range limit for the left wheel, and the required torque for the right wheel represents the torque allocated to the right wheel of the second axle that meets the yaw moment range limit for the right wheel.

[0156] Based on the longitudinal target torque, the required torque of the left wheel and the required torque of the right wheel of the second shaft, the initial allocated torque of the first shaft is determined; wherein, the initial allocated torque of the first shaft represents the torque initially allocated to the main motor of the first shaft;

[0157] Based on the initial torque distribution of the first shaft, the required torque of the left wheel and the required torque of the right wheel of the second shaft, the first and second torque distributions of each drive motor are determined.

[0158] In one alternative embodiment, the first processing unit 401 is specifically used for:

[0159] Based on the vertical load ratio of the first and second axes, the longitudinal target torque is distributed to determine the total required torque of the second axis.

[0160] The desired yaw moment and the total required torque of the second axle are divided equally into two parts to obtain the required yaw moment for the left wheel and the required yaw moment for the right wheel of the second axle.

[0161] Based on the yaw torque capacity of the left wheel and the right wheel of the second axle, the required yaw torque of the left wheel and the required yaw torque of the right wheel are adjusted and compensated to obtain the processed required yaw torque of the left wheel and the processed required yaw torque of the right wheel.

[0162] The processed yaw moment demand of the left wheel is converted into torque to obtain the required torque of the left wheel. The processed yaw moment demand of the right wheel is also converted into torque to obtain the required torque of the right wheel.

[0163] In one alternative embodiment, the first processing unit 401 is specifically used for:

[0164] Based on the initial allocated torque of the first shaft and the torque limit range of the main motor of the first shaft, determine the motor requirement torque of the first shaft; wherein, the motor requirement torque of the first shaft must be within the torque limit range of the main motor of the first shaft.

[0165] The sum of the motor torque required by the first shaft, the left wheel torque required by the second shaft, and the right wheel torque required by the second shaft is calculated to obtain the first total torque;

[0166] If the first total torque is determined to be within the total range of motor torque limits, then the motor demand torque of the first shaft is determined as the first allocated torque of the main motor of the first shaft, the left wheel demand torque of the second shaft is determined as the first allocated torque of the left wheel motor of the second shaft, and the right wheel demand torque of the second shaft is determined as the first allocated torque of the right wheel motor of the second shaft.

[0167] The first distributed torque of the main motor of the first shaft, the first distributed torque of the left wheel motor of the second shaft, and the first distributed torque of the right wheel motor of the second shaft are calculated to obtain the second total torque.

[0168] If the second total torque is determined to be equal to the longitudinal target torque, then the first distribution torque of the main motor of the first shaft is determined as the second distribution torque of the main motor of the first shaft, the first distribution torque of the left wheel motor of the second shaft is determined as the second distribution torque of the left wheel motor of the second shaft, and the first distribution torque of the right wheel motor of the second shaft is determined as the second distribution torque of the right wheel motor of the second shaft.

[0169] In one alternative embodiment, the first processing unit 401 is further configured to:

[0170] If it is determined that the first total torque exceeds the total range of motor torque limits, then calculate the first torque difference that exceeds the total range of motor torque limits;

[0171] The motor demand torque of the first shaft is adjusted according to the first torque difference, and the adjusted motor demand torque of the first shaft is determined to be the first allocated torque of the main motor of the first shaft; wherein the adjusted motor demand torque of the first shaft is located within the torque limit range of the main motor of the first shaft.

[0172] If it is determined that the first torque difference is entirely used to adjust the motor torque required by the first shaft, then the left wheel torque required by the second shaft is determined as the first distributed torque of the left wheel motor of the second shaft, and the right wheel torque required by the second shaft is determined as the first distributed torque of the right wheel motor of the second shaft.

[0173] If it is determined that the first torque difference is only partially used to adjust the motor torque demand of the first shaft, then a first residual torque difference is determined, and based on the first residual torque difference, the left wheel torque demand and right wheel torque demand of the second shaft are adjusted by an equal amount. The adjusted left wheel torque demand is determined as the first distributed torque of the left wheel motor of the second shaft, and the adjusted right wheel torque demand is determined as the first distributed torque of the right wheel motor of the second shaft. The adjusted left wheel torque demand is located within the torque limit range of the left wheel motor of the second shaft, and the adjusted right wheel torque demand is located within the torque limit range of the right wheel motor of the second shaft.

[0174] In one alternative embodiment, the first processing unit 401 is further configured to:

[0175] If it is determined that the second total torque is not equal to the longitudinal target torque, then calculate the second torque difference between the second total torque and the longitudinal target torque;

[0176] The first distribution torque of the main motor of the first shaft is adjusted according to the second torque difference, and the adjusted first distribution torque of the main motor of the first shaft is determined as the second distribution torque of the main motor of the first shaft; wherein, the adjusted first distribution torque of the main motor of the first shaft is located within the torque limit range of the main motor of the first shaft.

[0177] If it is determined that the second torque difference is entirely used to adjust the first distribution torque of the main motor of the first shaft, then the first distribution torque of the left wheel motor of the second shaft is determined as the second distribution torque of the left wheel motor of the second shaft, and the first distribution torque of the right wheel motor of the second shaft is determined as the second distribution torque of the right wheel motor of the second shaft.

[0178] If it is determined that the second torque difference is only partially used to adjust the first distribution torque of the main motor of the first shaft, then the second remaining torque difference is determined, and the first distribution torque of the left wheel motor of the second shaft and the first distribution torque of the right wheel motor of the second shaft are adjusted by the same amount according to the second remaining torque difference. The adjusted first distribution torque of the left wheel motor of the second shaft is determined as the second distribution torque of the left wheel motor of the second shaft, and the adjusted first distribution torque of the right wheel motor of the second shaft is determined as the second distribution torque of the right wheel motor of the second shaft.

[0179] Specifically, the first distributed torque of the adjusted left wheel motor of the second axle is located within the torque limit range of the left wheel motor of the second axle, and the first distributed torque of the adjusted right wheel motor of the second axle is located within the torque limit range of the right wheel motor of the second axle.

[0180] In one alternative embodiment, the second processing unit 402 is specifically used for:

[0181] Determine the first weighting coefficient and the second weighting coefficient; wherein the first weighting coefficient is the weighting coefficient corresponding to the first allocated torque, and the second weighting coefficient is the weighting coefficient corresponding to the second allocated torque;

[0182] Based on the first and second weighting coefficients, the first and second allocated torques of the drive motor are weighted and summed to obtain the target torque of the drive motor.

[0183] In one alternative embodiment, the second processing unit 402 is specifically used for:

[0184] Calculate the first deviation between the longitudinal target torque and the sum of the first distributed torques of each drive motor, and calculate the second deviation between the vehicle's expected yaw rate and the actual yaw rate.

[0185] Based on the first deviation and the second deviation, the first weighting coefficient and the second weighting coefficient are determined; wherein the first weighting coefficient is positively correlated with the second deviation and negatively correlated with the first deviation.

[0186] In one alternative embodiment, the first processing unit 401, before performing torque distribution processing based on the vehicle's desired yaw moment and longitudinal target torque to determine the first and second distribution torques for each drive motor, is further configured to:

[0187] Obtain the vehicle's steering wheel angle, vehicle speed, current road surface adhesion coefficient, and actual yaw rate;

[0188] Determine the initial yaw rate by referring to the table based on the steering wheel angle and vehicle speed, and adjust the initial yaw rate according to the road surface adhesion coefficient to obtain the desired yaw rate;

[0189] Determine the desired yaw acceleration based on the desired yaw rate and the actual yaw rate;

[0190] The feedforward yaw moment is obtained by calculating the product of the desired yaw acceleration and the vehicle's moment of inertia about the vertical axis.

[0191] The feedback yaw torque is calculated based on the deviation between the expected yaw rate and the actual yaw rate.

[0192] The sum of the feedforward yaw moment and the feedback yaw moment is calculated to obtain the desired yaw moment.

[0193] As can be seen from the above, the torque distribution device of the distributed drive system provided in this embodiment of the invention first decouples the vehicle's yaw stability requirements from its longitudinal driving requirements. Then, through a dynamic weighted fusion mechanism, it can adaptively balance yaw control and longitudinal requirements. This allows the torque control system to respond quickly to emergency control commands while also considering cruising efficiency and smoothness. This collaborative control scheme fully leverages the architectural advantages of single-motor centralized drive and dual-motor distributed drive, comprehensively improving vehicle safety, handling, and comfort while effectively optimizing system load distribution and energy efficiency. It enhances the adaptability and reliability of the drive system under all operating conditions, achieving overall optimization of vehicle dynamic performance. Furthermore, this invention uses the desired yaw moment determined based on the road surface adhesion coefficient, thereby ensuring the adaptability of the control strategy to actual road conditions, enhancing the control reliability of the vehicle on low-adhesion roads, and reducing the risk of sideslip.

[0194] Figure 5 The diagram shows a structural schematic of an embodiment of an electronic device provided by the present invention. The specific embodiments of the present invention do not limit the specific implementation of the electronic device.

[0195] like Figure 5 As shown, the electronic device may include: a processor 502, a communications interface 504, a memory 506, and a communications bus 508.

[0196] The processor 502, communication interface 504, and memory 506 communicate with each other via communication bus 508. Communication interface 504 is used to communicate with other network elements, such as clients or other servers. Processor 502 executes program 510, specifically performing the relevant steps described in the embodiment of the torque distribution method for a distributed drive system.

[0197] Specifically, program 510 may include program code, which includes computer-executable instructions.

[0198] Processor 502 may be a central processing unit (CPU), an application-specific integrated circuit (ASIC), or one or more integrated circuits configured to implement embodiments of the present invention. The electronic device includes one or more processors, which may be processors of the same type, such as one or more CPUs; or they may be processors of different types, such as one or more CPUs and one or more ASICs.

[0199] Memory 506 is used to store program 510. Memory 506 may include high-speed RAM memory, and may also include non-volatile memory, such as at least one disk storage device.

[0200] Specifically, program 510 can be called by processor 502 to cause the electronic device to perform the following operations:

[0201] Based on the vehicle's expected yaw moment and longitudinal target torque, torque distribution processing is performed to determine the first and second distribution torques for each drive motor.

[0202] Among them, the expected yaw moment represents the yaw moment determined by the user based on the current road surface adhesion coefficient, and the longitudinal target torque represents the driving torque expected by the user; the drive motor includes the main motor of the first shaft, the left wheel motor and the right wheel motor of the second shaft; the first allocated torque represents the torque allocated to achieve the expected yaw moment, and the second allocated torque represents the torque allocated to achieve the longitudinal target torque;

[0203] The first and second distributed torques of the drive motor are fused together to determine the target torque of the drive motor.

[0204] In one alternative approach, torque distribution processing is performed based on the vehicle's desired yaw moment and longitudinal target torque to determine a first distribution torque and a second distribution torque for each drive motor, including:

[0205] Based on the desired yaw moment and the target longitudinal torque, an initial torque distribution is performed to determine the required torque for the left wheel and the required torque for the right wheel of the second axle. The required torque for the left wheel represents the torque allocated to the left wheel of the second axle that meets the yaw moment range limit for the left wheel, and the required torque for the right wheel represents the torque allocated to the right wheel of the second axle that meets the yaw moment range limit for the right wheel.

[0206] Based on the longitudinal target torque, the required torque of the left wheel and the required torque of the right wheel of the second shaft, the initial allocated torque of the first shaft is determined; wherein, the initial allocated torque of the first shaft represents the torque initially allocated to the main motor of the first shaft;

[0207] Based on the initial torque distribution of the first shaft, the required torque of the left wheel and the required torque of the right wheel of the second shaft, the first and second torque distributions of each drive motor are determined.

[0208] In one alternative approach, an initial torque distribution is performed based on the desired yaw moment and the target longitudinal torque to determine the required torque for the left and right wheels of the second axle, including:

[0209] Based on the vertical load ratio of the first and second axes, the longitudinal target torque is distributed to determine the total required torque of the second axis.

[0210] The desired yaw moment and the total required torque of the second axle are divided equally into two parts to obtain the required yaw moment for the left wheel and the required yaw moment for the right wheel of the second axle.

[0211] Based on the yaw torque capacity of the left wheel and the right wheel of the second axle, the required yaw torque of the left wheel and the required yaw torque of the right wheel are adjusted and compensated to obtain the processed required yaw torque of the left wheel and the processed required yaw torque of the right wheel.

[0212] The processed yaw moment of the left wheel is converted into torque to obtain the required torque of the left wheel. The processed yaw moment of the right wheel is also converted into torque to obtain the required torque of the right wheel.

[0213] In one alternative approach, the first and second distribution torques of each drive motor are determined based on the initial distribution torque of the first shaft, the required torque of the left wheel of the second shaft, and the required torque of the right wheel, including:

[0214] Based on the initial allocated torque of the first shaft and the torque limit range of the main motor of the first shaft, determine the motor requirement torque of the first shaft; wherein, the motor requirement torque of the first shaft must be within the torque limit range of the main motor of the first shaft.

[0215] The sum of the motor torque required by the first shaft, the left wheel torque required by the second shaft, and the right wheel torque required by the second shaft is calculated to obtain the first total torque;

[0216] If the first total torque is determined to be within the total range of motor torque limits, then the motor demand torque of the first shaft is determined as the first allocated torque of the main motor of the first shaft, the left wheel demand torque of the second shaft is determined as the first allocated torque of the left wheel motor of the second shaft, and the right wheel demand torque of the second shaft is determined as the first allocated torque of the right wheel motor of the second shaft.

[0217] The first distributed torque of the main motor of the first shaft, the first distributed torque of the left wheel motor of the second shaft, and the first distributed torque of the right wheel motor of the second shaft are calculated to obtain the second total torque.

[0218] If the second total torque is determined to be equal to the longitudinal target torque, then the first distribution torque of the main motor of the first shaft is determined as the second distribution torque of the main motor of the first shaft, the first distribution torque of the left wheel motor of the second shaft is determined as the second distribution torque of the left wheel motor of the second shaft, and the first distribution torque of the right wheel motor of the second shaft is determined as the second distribution torque of the right wheel motor of the second shaft.

[0219] In an alternative embodiment, the method of the present invention further includes:

[0220] If it is determined that the first total torque exceeds the total range of motor torque limits, then calculate the first torque difference that exceeds the total range of motor torque limits;

[0221] The motor demand torque of the first shaft is adjusted according to the first torque difference, and the adjusted motor demand torque of the first shaft is determined to be the first allocated torque of the main motor of the first shaft; wherein the adjusted motor demand torque of the first shaft is located within the torque limit range of the main motor of the first shaft.

[0222] If it is determined that the first torque difference is entirely used to adjust the motor torque required by the first shaft, then the left wheel torque required by the second shaft is determined as the first distributed torque of the left wheel motor of the second shaft, and the right wheel torque required by the second shaft is determined as the first distributed torque of the right wheel motor of the second shaft.

[0223] If it is determined that the first torque difference is only partially used to adjust the motor torque demand of the first shaft, then a first residual torque difference is determined, and based on the first residual torque difference, the left wheel torque demand and right wheel torque demand of the second shaft are adjusted by an equal amount. The adjusted left wheel torque demand is determined as the first distributed torque of the left wheel motor of the second shaft, and the adjusted right wheel torque demand is determined as the first distributed torque of the right wheel motor of the second shaft. The adjusted left wheel torque demand is located within the torque limit range of the left wheel motor of the second shaft, and the adjusted right wheel torque demand is located within the torque limit range of the right wheel motor of the second shaft.

[0224] In one alternative embodiment, the method of the present invention further includes:

[0225] If it is determined that the second total torque is not equal to the longitudinal target torque, then calculate the second torque difference between the second total torque and the longitudinal target torque;

[0226] The first distribution torque of the main motor of the first shaft is adjusted according to the second torque difference, and the adjusted first distribution torque of the main motor of the first shaft is determined as the second distribution torque of the main motor of the first shaft; wherein, the adjusted first distribution torque of the main motor of the first shaft is located within the torque limit range of the main motor of the first shaft.

[0227] If it is determined that the second torque difference is entirely used to adjust the first distribution torque of the main motor of the first shaft, then the first distribution torque of the left wheel motor of the second shaft is determined as the second distribution torque of the left wheel motor of the second shaft, and the first distribution torque of the right wheel motor of the second shaft is determined as the second distribution torque of the right wheel motor of the second shaft.

[0228] If it is determined that the second torque difference is only partially used to adjust the first distribution torque of the main motor of the first shaft, then the second remaining torque difference is determined, and the first distribution torque of the left wheel motor of the second shaft and the first distribution torque of the right wheel motor of the second shaft are adjusted by the same amount according to the second remaining torque difference. The adjusted first distribution torque of the left wheel motor of the second shaft is determined as the second distribution torque of the left wheel motor of the second shaft, and the adjusted first distribution torque of the right wheel motor of the second shaft is determined as the second distribution torque of the right wheel motor of the second shaft.

[0229] Specifically, the first distributed torque of the adjusted left wheel motor of the second axle is located within the torque limit range of the left wheel motor of the second axle, and the first distributed torque of the adjusted right wheel motor of the second axle is located within the torque limit range of the right wheel motor of the second axle.

[0230] In one alternative approach, the first and second distributed torques of the drive motor are fused to determine the target torque of the drive motor, including:

[0231] Determine the first weighting coefficient and the second weighting coefficient; wherein the first weighting coefficient is the weighting coefficient corresponding to the first allocated torque, and the second weighting coefficient is the weighting coefficient corresponding to the second allocated torque;

[0232] Based on the first and second weighting coefficients, the first and second allocated torques of the drive motor are weighted and summed to obtain the target torque of the drive motor.

[0233] In one alternative approach, determining the first weighting coefficient and the second weighting coefficient includes:

[0234] Calculate the first deviation between the longitudinal target torque and the sum of the first distributed torques of each drive motor, and calculate the second deviation between the vehicle's expected yaw rate and the actual yaw rate.

[0235] Based on the first deviation and the second deviation, the first weighting coefficient and the second weighting coefficient are determined; wherein the first weighting coefficient is positively correlated with the second deviation and negatively correlated with the first deviation.

[0236] In one alternative approach, before determining the first and second distribution torques for each drive motor by performing torque distribution processing based on the vehicle's desired yaw moment and longitudinal target torque, the method further includes:

[0237] Obtain the vehicle's steering wheel angle, vehicle speed, current road surface adhesion coefficient, and actual yaw rate;

[0238] Determine the initial yaw rate by referring to the table based on the steering wheel angle and vehicle speed, and adjust the initial yaw rate according to the road surface adhesion coefficient to obtain the desired yaw rate;

[0239] Determine the desired yaw acceleration based on the desired yaw rate and the actual yaw rate;

[0240] The feedforward yaw moment is obtained by calculating the product of the desired yaw acceleration and the vehicle's moment of inertia about the vertical axis.

[0241] The feedback yaw torque is calculated based on the deviation between the expected yaw rate and the actual yaw rate.

[0242] The sum of the feedforward yaw moment and the feedback yaw moment is calculated to obtain the desired yaw moment.

[0243] As can be seen from the above, the electronic device provided in this embodiment of the invention first decouples the vehicle's yaw stability requirements from its longitudinal driving requirements. Then, through a dynamically weighted fusion mechanism, it can adaptively balance yaw control and longitudinal requirements. This allows the torque control system to respond quickly to emergency control commands while also considering cruising efficiency and smoothness. This collaborative control scheme fully leverages the architectural advantages of single-motor centralized drive and dual-motor distributed drive, comprehensively improving vehicle safety, handling, and comfort while effectively optimizing system load distribution and energy efficiency. It enhances the adaptability and reliability of the drive system under all operating conditions, achieving overall optimization of vehicle dynamic performance. Furthermore, this invention uses the desired yaw moment determined based on the road surface adhesion coefficient, thereby ensuring the adaptability of the control strategy to actual road conditions, enhancing the vehicle's control reliability on low-adhesion roads, and reducing the risk of sideslip.

[0244] This invention also provides a vehicle that includes any of the electronic devices described in the above embodiments.

[0245] This invention also provides a computer-readable storage medium storing at least one executable instruction that, when executed on an electronic device / app, causes the electronic device / app to perform the torque distribution method of the distributed drive system in any of the above method embodiments.

[0246] The algorithms or displays provided herein are not inherently related to any particular computer, virtual system, or other device. Furthermore, the embodiments of this invention are not directed to any particular programming language.

[0247] Numerous specific details are set forth in the specification provided herein. However, it will be understood that embodiments of the invention may be practiced without these specific details. Similarly, for the sake of brevity and to aid in understanding one or more aspects of the invention, in the description of exemplary embodiments of the invention above, various features of the embodiments are sometimes grouped together in a single embodiment, figure, or description thereof. The claims, which follow the detailed description, are hereby expressly incorporated into that detailed description, wherein each claim itself is a separate embodiment of the invention.

[0248] Those skilled in the art will understand that the modules in the device of the embodiment can be adaptively changed and placed in one or more devices different from that embodiment. Modules, units, or components in the embodiment can be combined into a single module, unit, or component, and further, they can be divided into multiple sub-modules, sub-units, or sub-components, except that at least some of such features and / or processes or units are mutually exclusive.

[0249] It should be noted that the above embodiments are illustrative of the invention and not restrictive, and that those skilled in the art can devise alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses should not be construed as limiting the claims. The word "comprising" does not exclude the presence of elements or steps not listed in the claims. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. The invention can be implemented by means of hardware comprising several different elements and by means of a suitably programmed computer. In the unit claims enumerating several means, several of these means may be embodied by the same item of hardware. The use of the words first, second, and third, etc., does not indicate any order. These words can be interpreted as names. The steps in the above embodiments, unless otherwise specified, should not be construed as limiting the order of execution.

Claims

1. A torque distribution method for a distributed drive system, characterized in that, The distributed drive system uses a single-motor centralized drive for the first axis and a dual-motor distributed drive for the second axis. The first axis can be a front or rear axle. The method includes: Based on the vehicle's expected yaw moment and longitudinal target torque, torque distribution processing is performed to determine the first and second distribution torques for each drive motor. Wherein, the desired yaw moment represents the yaw moment expected by the user, determined based on the road surface adhesion coefficient of the current road surface, and the longitudinal target torque represents the driving torque expected by the user; the drive motor includes the main motor of the first axle, the left wheel motor and the right wheel motor of the second axle; the first allocated torque represents the torque allocated to achieve the desired yaw moment, and the second allocated torque represents the torque allocated to achieve the longitudinal target torque; The first and second allocated torques of the drive motor are fused together to determine the target torque of the drive motor.

2. The method according to claim 1, characterized in that, The process of torque distribution based on the vehicle's desired yaw moment and longitudinal target torque, determining the first and second distribution torques for each drive motor, includes: Based on the desired yaw moment and the longitudinal target torque, an initial torque allocation is performed to determine the required torque for the left wheel and the required torque for the right wheel of the second axle; wherein, the required torque for the left wheel represents the torque allocated to the left wheel of the second axle that satisfies the yaw moment range limit of the left wheel, and the required torque for the right wheel represents the torque allocated to the right wheel of the second axle that satisfies the yaw moment range limit of the right wheel; Based on the longitudinal target torque, the required torque of the left wheel and the required torque of the right wheel of the second shaft, the initial allocated torque of the first shaft is determined; wherein, the initial allocated torque of the first shaft represents the torque initially allocated to the main motor of the first shaft; Based on the initial allocated torque of the first shaft, the required torque of the left wheel and the required torque of the right wheel of the second shaft, the first allocated torque and the second allocated torque of each drive motor are determined.

3. The method according to claim 2, characterized in that, The step of performing initial torque allocation based on the desired yaw moment and the target longitudinal torque to determine the required torque for the left and right wheels of the second axle includes: Based on the vertical load ratio of the first shaft and the second shaft, the longitudinal target torque is allocated to determine the total required torque of the second shaft. The desired yaw moment and the total required torque of the second shaft are averaged and divided into two equal parts to obtain the required yaw moment for the left wheel and the required yaw moment for the right wheel of the second shaft. Based on the yaw torque capacity of the left wheel and the yaw torque capacity of the right wheel of the second axle, the required yaw torque of the left wheel and the required yaw torque of the right wheel are adjusted and compensated to obtain the processed required yaw torque of the left wheel and the processed required yaw torque of the right wheel. The processed yaw moment of the left wheel is converted into torque to obtain the required torque of the left wheel. The processed yaw moment of the right wheel is also converted into torque to obtain the required torque of the right wheel.

4. The method according to claim 2, characterized in that, The step of determining the first and second distribution torques of each drive motor based on the initial distribution torque of the first shaft, the required torque of the left wheel of the second shaft, and the required torque of the right wheel includes: The motor requirement torque of the first shaft is determined based on the initial allocated torque of the first shaft and the torque limit range of the main motor of the first shaft; wherein, the motor requirement torque of the first shaft must be within the torque limit range of the main motor of the first shaft. The sum of the motor torque required by the first shaft, the left wheel torque required by the second shaft, and the right wheel torque required by the second shaft is calculated to obtain the first total torque; If it is determined that the first total torque is within the total range of motor torque limits, then the motor demand torque of the first shaft is determined as the first allocated torque of the main motor of the first shaft, the left wheel demand torque of the second shaft is determined as the first allocated torque of the left wheel motor of the second shaft, and the right wheel demand torque of the second shaft is determined as the first allocated torque of the right wheel motor of the second shaft. The first distributed torque of the main motor of the first shaft, the first distributed torque of the left wheel motor of the second shaft, and the first distributed torque of the right wheel motor of the second shaft are calculated to obtain the second total torque. If it is determined that the second total torque is equal to the longitudinal target torque, then the first distribution torque of the main motor of the first shaft is determined as the second distribution torque of the main motor of the first shaft, the first distribution torque of the left wheel motor of the second shaft is determined as the second distribution torque of the left wheel motor of the second shaft, and the first distribution torque of the right wheel motor of the second shaft is determined as the second distribution torque of the right wheel motor of the second shaft.

5. The method according to claim 4, characterized in that, The method further includes: If it is determined that the first total torque exceeds the total range of motor torque limits, then calculate the first torque difference value that exceeds the total range of motor torque limits; The motor demand torque of the first shaft is adjusted according to the first torque difference, and the adjusted motor demand torque of the first shaft is determined to be the first allocated torque of the main motor of the first shaft; wherein the adjusted motor demand torque of the first shaft is located within the torque limit range of the main motor of the first shaft. If it is determined that the first torque difference is entirely used to adjust the motor torque demand of the first shaft, then the left wheel torque demand of the second shaft is determined as the first allocated torque of the left wheel motor of the second shaft, and the right wheel torque demand of the second shaft is determined as the first allocated torque of the right wheel motor of the second shaft. If it is determined that the first torque difference is only partially used to adjust the motor torque demand of the first shaft, then a first residual torque difference is determined, and the left wheel torque demand and right wheel torque demand of the second shaft are adjusted by an equal amount based on the first residual torque difference. The adjusted left wheel torque demand is determined as the first allocated torque of the left wheel motor of the second shaft, and the adjusted right wheel torque demand is determined as the first allocated torque of the right wheel motor of the second shaft. The adjusted left wheel torque demand is located within the torque limit range of the left wheel motor of the second shaft, and the adjusted right wheel torque demand is located within the torque limit range of the right wheel motor of the second shaft.

6. The method according to claim 4, characterized in that, The method further includes: If it is determined that the second total torque is not equal to the longitudinal target torque, then calculate the second torque difference between the second total torque and the longitudinal target torque; The first distribution torque of the main motor of the first shaft is adjusted according to the second torque difference, and the adjusted first distribution torque of the main motor of the first shaft is determined as the second distribution torque of the main motor of the first shaft; wherein the adjusted first distribution torque of the main motor of the first shaft is located within the torque limit range of the main motor of the first shaft. If it is determined that the second torque difference is entirely used to adjust the first distribution torque of the main motor of the first shaft, then the first distribution torque of the left wheel motor of the second shaft is determined as the second distribution torque of the left wheel motor of the second shaft, and the first distribution torque of the right wheel motor of the second shaft is determined as the second distribution torque of the right wheel motor of the second shaft. If it is determined that the second torque difference is only partially used to adjust the first distribution torque of the main motor of the first shaft, then a second remaining torque difference is determined, and the first distribution torque of the left wheel motor of the second shaft and the first distribution torque of the right wheel motor of the second shaft are adjusted by an equal amount according to the second remaining torque difference. The adjusted first distribution torque of the left wheel motor of the second shaft is determined as the second distribution torque of the left wheel motor of the second shaft, and the adjusted first distribution torque of the right wheel motor of the second shaft is determined as the second distribution torque of the right wheel motor of the second shaft. Wherein, the first distributed torque of the adjusted left wheel motor of the second shaft is located within the torque limit range of the left wheel motor of the second shaft, and the first distributed torque of the adjusted right wheel motor of the second shaft is located within the torque limit range of the right wheel motor of the second shaft.

7. The method according to claim 1, characterized in that, The step of fusing the first and second allocated torques of the drive motor to determine the target torque of the drive motor includes: Determine a first weighting coefficient and a second weighting coefficient; wherein the first weighting coefficient is the weighting coefficient corresponding to the first allocated torque, and the second weighting coefficient is the weighting coefficient corresponding to the second allocated torque; Based on the first weighting coefficient and the second weighting coefficient, the first allocated torque and the second allocated torque of the drive motor are weighted and summed to obtain the target torque of the drive motor.

8. The method according to claim 7, characterized in that, Determining the first weighting coefficient and the second weighting coefficient includes: Calculate the first deviation between the longitudinal target torque and the sum of the first distributed torques of each of the drive motors, and calculate the second deviation between the desired yaw rate of the vehicle and the actual yaw rate; Based on the first deviation and the second deviation, the first weighting coefficient and the second weighting coefficient are determined; wherein the first weighting coefficient is positively correlated with the second deviation and negatively correlated with the first deviation.

9. The method according to any one of claims 1-8, characterized in that, Before determining the first and second distribution torques for each drive motor by performing torque distribution processing based on the vehicle's desired yaw moment and longitudinal target torque, the method further includes: Obtain the vehicle's steering wheel angle, vehicle speed, current road surface adhesion coefficient, and actual yaw rate; The initial yaw rate is determined by looking up the steering wheel angle and vehicle speed in a table, and the initial yaw rate is adjusted according to the road surface adhesion coefficient to obtain the desired yaw rate. The desired yaw rate is determined based on the desired yaw rate and the actual yaw rate. The feedforward yaw moment is obtained by calculating the product of the desired yaw acceleration and the vehicle's moment of inertia about the vertical axis. The feedback yaw torque is calculated based on the deviation between the desired yaw rate and the actual yaw rate. The desired yaw moment is obtained by calculating the sum of the feedforward yaw moment and the feedback yaw moment.

10. A torque distribution device for a distributed drive system, characterized in that, The distributed drive system uses a single-motor centralized drive for the first axis and a dual-motor distributed drive for the second axis. The first axis can be a front or rear axle. The device includes: The first processing unit is used to perform torque distribution processing based on the vehicle's desired yaw moment and longitudinal target torque, and to determine the first and second distribution torques of each drive motor. Wherein, the desired yaw moment represents the yaw moment expected by the user, determined based on the road surface adhesion coefficient of the current road surface, and the longitudinal target torque represents the driving torque expected by the user; the drive motor includes the main motor of the first axle, the left wheel motor and the right wheel motor of the second axle; the first allocated torque represents the torque allocated to achieve the desired yaw moment, and the second allocated torque represents the torque allocated to achieve the longitudinal target torque; The second processing unit is used to fuse the first allocated torque and the second allocated torque of the drive motor to determine the target torque of the drive motor.

11. An electronic device, characterized in that, include: The processor, memory, communication interface, and communication bus are provided, wherein the processor, memory, and communication interface communicate with each other via the communication bus. The memory is used to store at least one executable instruction that causes the processor to perform the operation of the torque distribution method of the distributed drive system as described in any one of claims 1-9.

12. A car, characterized in that, Including the electronic device as described in claim 11.

13. A computer-readable storage medium, characterized in that, The storage medium stores at least one executable instruction, which, when executed on an electronic device, causes the electronic device to perform the operation of the torque distribution method of the distributed drive system as described in any one of claims 1-9.

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