Torque distribution method, vehicle and storage medium

Abstract

The invention provides a torque distribution method, a vehicle and a storage medium, the method is applied to the technical field of hybrid power control, and the method comprises the steps that under the condition that the vehicle is in a running state, based on a driving mode and a driving mode of the vehicle, an initial torque proportion distributed to a first axle is determined; wherein the first axle is provided with a first motor and an engine; the initial torque ratio is corrected based on the remaining electric quantity of the power battery, and the target torque ratio of the first axle is obtained; wherein the smaller the residual electric quantity is, the larger the target torque ratio is; determining a first target torque distributed to the first axle and a second target torque distributed to the second axle based on the target torque ratio; the second axle is provided with a second motor. By means of the method, the electricity guaranteeing performance of the vehicle can be improved, the four-wheel-drive requirement of a user is better met, and the vehicle driving safety and the vehicle using experience of the user are improved.

Description

Technical Field

[0001] This application relates to the field of hybrid power control technology, and more specifically, to a torque distribution method, vehicle, and storage medium in the field of hybrid power control technology. Background Technology

[0002] Hybrid vehicles integrate both an engine and an electric motor as dual power sources, and can balance power output and energy economy by flexibly switching between various driving modes such as pure electric, series, and direct drive.

[0003] Some hybrid vehicles have electric motors on both the front and rear axles, allowing both axles to drive the vehicle and enabling four-wheel drive. When the vehicle is in four-wheel drive mode, a reasonable torque distribution between the front and rear axles is required to meet the user's driving needs.

[0004] In related technologies, the torque distribution between the front and rear axles is fixed based on the driving mode. The factors considered in the torque distribution are not comprehensive enough, which can easily cause the vehicle to lose its four-wheel drive performance, affecting the vehicle's driving safety and the user's driving experience. Summary of the Invention

[0005] This application provides a torque distribution method, a vehicle, and a storage medium. The method can improve the vehicle's power retention performance, better meet the user's four-wheel drive needs, and improve vehicle driving safety and user experience.

[0006] Firstly, a torque distribution method is provided, comprising: when the vehicle is in motion, determining an initial torque percentage allocated to a first axle based on the vehicle's drive mode and driving mode; wherein the first axle is equipped with a first motor and an engine; correcting the initial torque percentage based on the remaining charge of the power battery to obtain a target torque percentage for the first axle; wherein the smaller the remaining charge, the larger the target torque percentage; determining a first target torque allocated to the first axle and a second target torque allocated to a second axle based on the target torque percentage; wherein the second axle is equipped with a second motor.

[0007] In the above technical solution, torque is distributed based on the drive mode and driving mode during vehicle operation. This allows for torque distribution between the front and rear axles that takes both drive mode and driving mode into account, better meeting user needs. The torque ratio of the first axle is adjusted based on the remaining charge of the power battery. The lower the remaining charge, the higher the target torque ratio and the greater the requested torque for the first axle. Since the first axle is equipped with an engine and a drive motor, the engine bears more torque, increasing fuel consumption and reducing electricity consumption. This helps the vehicle conserve power and prevents it from easily entering series mode, which would cause it to lose four-wheel drive performance. This better meets user four-wheel drive needs, improves vehicle driving safety, and enhances the user experience.

[0008] In conjunction with the first aspect, in some possible implementations, the initial torque ratio is corrected based on the remaining power of the power battery to obtain the target torque ratio of the first axle, including: determining the first reference torque ratio of the first axle based on the remaining power and the vehicle speed; wherein, the smaller the remaining power, the larger the first reference torque ratio; and determining the maximum value between the initial torque ratio and the first reference torque ratio as the target torque ratio.

[0009] Combining the first aspect and the above implementation methods, in some possible implementation methods, after correcting the initial torque ratio based on the remaining charge of the power battery to obtain the target torque ratio of the first axle, the method further includes: determining whether the vehicle is in a forced charging mode; in the forced charging mode, the engine is forcibly started and the power battery is charged through the first motor; when the vehicle is not in the forced charging mode, the temperature of the first motor is obtained; the target torque ratio is corrected based on the temperature of the first motor to obtain the corrected target torque ratio; wherein, the higher the temperature of the first motor, the smaller the corrected target torque ratio.

[0010] In combination with the first aspect and the above implementation methods, in some possible implementation methods, before correcting the initial torque ratio based on the remaining power battery charge to obtain the target torque ratio of the first axle, the method further includes: obtaining the brake pedal opening and accelerator pedal opening of the vehicle; and determining, based on the brake pedal opening and accelerator pedal opening, that the vehicle is not in a coasting state and is not in a regenerative braking state.

[0011] Combining the first aspect and the above implementation methods, in some possible implementation methods, the first axle includes a first wheel, and the second axle includes a second wheel; after determining the initial torque ratio allocated to the first axle based on the vehicle's drive mode and driving mode, the method further includes: determining a reference speed based on a first average vehicle speed of the first wheel and a second average vehicle speed of the second wheel; determining the slip ratio of the first wheel based on the first average vehicle speed and the reference vehicle speed; and determining the slip ratio of the second wheel based on the second average vehicle speed and the reference vehicle speed; and correcting the initial torque ratio based on the slip ratio of the first wheel or the slip ratio of the second wheel to obtain the target torque ratio of the first axle.

[0012] In combination with the first aspect and the above implementation methods, in some possible implementation methods, the initial torque ratio is corrected based on the slip ratio of the first wheel or the slip ratio of the second wheel to obtain the target torque ratio of the first axle, including: determining a reference slip ratio based on a reference vehicle speed; when the slip ratio of the first wheel is greater than the reference slip ratio, correcting the initial torque ratio based on the slip ratio of the first wheel to obtain the target torque ratio of the first axle; when the slip ratio of the second wheel is greater than the reference slip ratio, correcting the initial torque ratio based on the slip ratio of the second wheel to obtain the target torque ratio of the first axle.

[0013] Combining the first aspect and the above implementation methods, in some possible implementation methods, the target torque ratio of the first axle is obtained by correcting the initial torque ratio based on the slip ratio of the first wheel, including: determining the second reference torque ratio of the first axle based on the slip ratio of the first wheel and the reference vehicle speed; and determining the minimum value between the initial torque ratio and the second reference torque ratio as the target torque ratio.

[0014] Combining the first aspect and the above implementation methods, in some possible implementation methods, the initial torque ratio is corrected based on the slip ratio of the second wheel to obtain the target torque ratio of the first axle, including: determining the third reference torque ratio of the first axle based on the slip ratio of the second wheel and the reference vehicle speed; and determining the maximum value between the initial torque ratio and the third reference torque ratio as the target torque ratio.

[0015] Secondly, a torque distribution device is provided, comprising: a determining module, configured to determine an initial torque percentage allocated to a first axle based on the vehicle's drive mode and driving mode when the vehicle is in motion; wherein the first axle is equipped with a first motor and an engine; a correcting module, configured to correct the initial torque percentage based on the remaining charge of the power battery to obtain a target torque percentage for the first axle; wherein the smaller the remaining charge, the larger the target torque percentage; and an allocating module, configured to determine a first target torque allocated to the first axle and a second target torque allocated to a second axle based on the target torque percentage; wherein the second axle is equipped with a second motor.

[0016] Thirdly, a vehicle is provided, including a memory and a processor. The memory is used to store executable program code, and the processor is used to call and run the executable program code from the memory, causing the vehicle to perform the methods of the first aspect or any possible implementation thereof.

[0017] Fourthly, a computer program product is provided, comprising: computer program code, which, when run on a computer, causes the computer to perform the methods described in the first aspect or any possible implementation thereof.

[0018] Fifthly, a computer-readable storage medium is provided that stores computer program code, which, when executed on a computer, causes the computer to perform the methods described in the first aspect or any possible implementation thereof. Attached Figure Description

[0019] Figure 1 This is a schematic flowchart of a torque distribution method provided in an embodiment of this application.

[0020] Figure 2This is a schematic diagram of the architecture of a hybrid vehicle provided in an embodiment of this application.

[0021] Figure 3 This is a flowchart of a method for correcting torque ratio based on remaining battery power, provided in an embodiment of this application.

[0022] Figure 4 This is a flowchart of a method for correcting torque ratio based on slip ratio provided in an embodiment of this application.

[0023] Figure 5 This is a flowchart of the method for correcting torque ratio provided in the embodiments of this application.

[0024] Figure 6 This is a schematic diagram of the structure of a torque distribution device provided in an embodiment of this application.

[0025] Figure 7 This is a schematic diagram of the structure of a vehicle provided in an embodiment of this application. Detailed Implementation

[0026] The technical solutions in this application will be clearly and thoroughly described below with reference to the accompanying drawings. In the description of the embodiments of this application, unless otherwise stated, " / " means "or," for example, A / B can mean A or B. "And / or" in the text is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Furthermore, in the description of the embodiments of this application, "multiple" refers to two or more than two.

[0027] Hereinafter, the terms "first" and "second" are used for descriptive purposes only and should not be construed as implying or suggesting relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature.

[0028] Hybrid vehicles integrate both an engine and an electric motor as power sources, balancing power output and fuel economy through flexible switching between various driving modes such as pure electric, series, and direct drive. Some hybrid vehicles have electric motors on both the front and rear axles, enabling four-wheel drive. When the vehicle is in four-wheel drive mode, a reasonable torque distribution between the front and rear axles is required to meet the user's driving needs.

[0029] In related technologies, torque is fixedly distributed based on the drive mode. However, the factors considered in torque distribution are not comprehensive enough, which can easily lead to the vehicle losing its four-wheel drive performance. For example, when the State of Charge (SOC) is low, if the vehicle is in direct-drive four-wheel drive mode, the torque is distributed according to the original front and rear axle torque distribution ratio. The rear motor has a higher proportion, the vehicle does not maintain power, and the SOC will continue to drop. When it falls below a certain level, the vehicle will be forced to enter series power generation. At this time, the vehicle loses its four-wheel drive performance, cannot meet the user's four-wheel drive needs, affects the vehicle's driving safety, and affects the user's driving experience.

[0030] Based on this, this application proposes a torque distribution method that can reduce the occurrence of vehicles losing four-wheel drive performance, meet users' four-wheel drive needs, and improve vehicle driving safety and user experience.

[0031] Figure 1 This is a schematic flowchart of a torque distribution method provided in an embodiment of this application.

[0032] For example, such as Figure 1 As shown, the method 100 includes: Step 101: When the vehicle is in motion, determine the initial torque percentage allocated to the first axle based on the vehicle's drive mode and driving mode; wherein the first axle is equipped with a first motor and an engine. Step 102: Adjust the initial torque ratio based on the remaining power battery charge to obtain the target torque ratio of the first axle; where the smaller the remaining power battery charge, the larger the target torque ratio. Step 103: Determine the first target torque to be allocated to the first axle and the second target torque to be allocated to the second axle based on the target torque ratio; wherein, the second axle is equipped with a second motor.

[0033] exist Figure 1 In the illustrated embodiment, torque is distributed based on the drive mode and driving mode during vehicle operation. This allows for torque distribution between the front and rear axles that considers both the drive mode and driving mode, better meeting user needs. The torque ratio of the first axle is adjusted based on the remaining battery charge. The lower the remaining charge, the higher the target torque ratio and the greater the requested torque for the first axle. Since the first axle is equipped with an engine and a drive motor, the engine bears more torque, increasing fuel consumption and reducing battery consumption. This helps conserve battery power and prevents the vehicle from easily entering series mode, which could cause a loss of four-wheel drive performance. This better meets user four-wheel drive needs, improves driving safety, and enhances the user experience.

[0034] The following is about Figure 1 The specific implementation methods of each step in the illustrated embodiments are explained in detail below: In step 101, the vehicle is a hybrid vehicle, including a first axle and a second axle. The first axle is equipped with a first motor and an engine, and the second axle is equipped with a second motor.

[0035] The first axle can be the front axle of the vehicle, and the first motor installed on the first axle can be called a front-drive motor, used to drive the front wheels of the vehicle. Correspondingly, the second axle is the rear axle of the vehicle, and the second motor installed on the second axle can be called a rear-drive motor, used to drive the rear wheels of the vehicle.

[0036] Alternatively, the first axle can also be the rear axle of the vehicle. In this case, the first motor installed on the first axle can be called a rear-drive motor, used to drive the rear wheels of the vehicle. Correspondingly, the second axle is the front axle of the vehicle, and the second motor installed on the second axle can be called a front-drive motor, used to drive the front wheels of the vehicle.

[0037] In this embodiment, the first axle is used as the front axle and the second axle as the rear axle for illustration. The vehicle's structure is as follows: Figure 2 As shown.

[0038] Figure 2 This is a schematic diagram of the architecture of a hybrid vehicle provided in an embodiment of this application.

[0039] For example, such as Figure 2 As shown, the hybrid vehicle 200 includes: an engine 201, a clutch 202, a front drive motor 203, a transmission 204, a rear drive motor 205, a power battery 206, a left front wheel 2071, a right front wheel 2072, a left rear wheel 2081, and a right rear wheel 2082.

[0040] The engine 201 is one of the vehicle's power sources, generating power by burning fuel (such as gasoline or diesel). The power generated by the engine is transmitted through the crankshaft to the clutch 202 and the gearbox 204, ultimately driving the front wheels of the hybrid vehicle 200.

[0041] Clutch 202 is used to disconnect or connect the mechanical connection between engine 201 and transmission 204. Clutch 202 has two states: open and closed. When clutch 202 is in the open state, the connection between engine 201 and transmission 204 is broken, and even if engine 201 is running, the power it generates will not be transmitted to transmission 204. When clutch 202 is in the closed state, the mechanical connection between engine 201 and transmission 204 is established, and the power generated by engine 201 can be transmitted to transmission 204.

[0042] The front drive motor 203 is connected to both the gearbox 204 and the clutch 202. The front drive motor 203 is used to drive the front wheels of the vehicle through the gearbox 204 or to work as a generator through the clutch 202.

[0043] As one embodiment, when the front drive motor 203 is working as a generator, the clutch 202 is in a closed state, and the engine 201 drives the front drive motor 203 to generate electricity through the clutch 202.

[0044] The transmission 204 is located on the front axle of the vehicle and can also be called a front axle transmission. The transmission 204 is used to change the speed and torque output by the engine 201 to adapt to different driving conditions and ensure that the vehicle operates efficiently under different speed and load conditions.

[0045] The transmission 204 may include multiple gears, such as 1st gear, 2nd gear, 3rd gear, and 4th gear. When the transmission 204 is in any of the 1st, 2nd, 3rd, or 4th gear positions, the power from the front drive motor 203 or the engine 201 can be transmitted to the front wheels of the vehicle to drive the vehicle.

[0046] The rear drive motor 205, also known as the P4 motor, transmits power to the rear wheels of the vehicle when it is running, driving the vehicle.

[0047] The power battery 206, also known as a high-voltage battery, supplies power to the front drive motor 203 and the rear drive motor 205, enabling the front drive motor 203 and the rear drive motor 205 to output torque and drive the vehicle.

[0048] When engine 201 drives front drive motor 203 to generate electricity via clutch 202, the electrical energy generated by front drive motor 203 can also charge power battery 206. Alternatively, the electrical energy generated by front drive motor 203 can be directly supplied to rear drive motor 205 to drive the vehicle.

[0049] Understandable, Figure 2 This is merely a schematic diagram of a hybrid vehicle architecture, and the embodiments of this application do not impose specific limitations on the architecture of hybrid vehicles.

[0050] The aforementioned vehicle is specifically in four-wheel drive mode. Four-wheel drive mode means that both the first and second axles of the vehicle are outputting power to drive the vehicle. In this state, torque needs to be distributed between the first and second axles.

[0051] Drive mode refers to the operating mode and collaborative logic of various subsystems in a vehicle under different operating conditions. Drive mode is typically selected automatically by the vehicle's control unit (such as the power management system and energy management system) based on current driving conditions and vehicle status to ensure optimal vehicle operating efficiency and safety. Vehicle drive modes can include various modes such as: series drive, direct-drive four-wheel drive, hybrid front-wheel drive, pure electric four-wheel drive, pure electric rear-wheel drive, and pure electric front-wheel drive.

[0052] In direct-drive four-wheel drive mode, the engine on the first axle is running, outputting power to drive the vehicle; the second motor on the second axle is running, outputting power to drive the vehicle. The vehicle is in four-wheel drive mode.

[0053] In pure electric four-wheel drive mode, the first motor on the first axle is operational, outputting power to drive the vehicle; the second motor on the second axle is also operational, outputting power to drive the vehicle. The vehicle is in four-wheel drive mode in pure electric mode.

[0054] Driving modes refer to the ways in which a vehicle adjusts the operation of its engine, transmission, suspension system, steering system, and other components based on the driver's preferences and road conditions to provide different driving experiences and performance characteristics. The main purpose of driving modes is to optimize the vehicle's dynamic response and meet the driver's needs. Driving modes are typically selected by the user. Vehicle driving modes may include: Eco mode, Sport mode, Standard mode, Snow mode, Mud mode, Sand mode, etc.

[0055] Different drive modes and different driving modes require different torque from the front and rear axles. Therefore, it is necessary to determine the initial torque ratio allocated to the first axle based on the drive mode and driving mode.

[0056] The torque percentage of the first axle is used to distribute the requested torque of the entire vehicle. Specifically, when the driver presses the accelerator pedal, the requested torque of the entire vehicle can be determined based on the opening of the accelerator pedal. After obtaining the torque percentage of the first axle, the requested torque of the entire vehicle can be multiplied by the torque percentage of the first axle to obtain the torque distributed to the first axle. The requested torque of the entire vehicle is then subtracted from the torque of the first axle to obtain the torque distributed to the second axle.

[0057] Specifically, the vehicle can store a first correspondence between the vehicle speed and the actual torque of the first axle in each driving mode corresponding to the direct-drive four-wheel drive mode, and the initial torque ratio of the first axle; and a second correspondence between the vehicle speed and the actual torque of the first axle in each driving mode corresponding to the pure electric four-wheel drive mode, and the initial torque ratio of the first axle. Both the first and second correspondences include multiple correspondences for different driving modes.

[0058] As one implementation method, when the vehicle is in four-wheel drive mode, the vehicle's drive mode and driving mode are determined. Based on the drive mode and driving mode, the target correspondence is determined from the first correspondence and the second correspondence. Then, the vehicle speed and the actual torque of the first axle are obtained. Based on the vehicle speed and the actual torque, the target correspondence is found to obtain the initial torque ratio of the first axle.

[0059] For example, the current vehicle's drive mode is direct drive four-wheel drive mode, and the driving mode is sport mode. The target correspondence determined based on the direct drive four-wheel drive mode and the sport mode is shown in Table 1 below: Table 1

[0060] In the target correspondence shown in Table 1, x represents vehicle speed in kph (kilometers per hour), and y represents the actual torque of the first axle in Nm (Newton-meters). The vehicle speed and the actual torque of the first axle correspond to the initial torque percentage of the first axle, expressed as a percentage. In the target correspondence shown in Table 1, the initial torque percentage of the first axle increases with increasing vehicle speed.

[0061] It is understood that Table 1 is only an example, and the initial torque ratio in the above correspondence can be calibrated based on the actual situation. This application embodiment does not limit this.

[0062] Assuming the current vehicle speed is 120 kph and the actual torque of the first axle is 1500 Nm, then by looking up Table 1, we can determine that the initial torque percentage of the first axle is 55%.

[0063] Understandably, the correspondence between the same driving mode and different driving modes is different; therefore, the determined initial torque percentage may differ depending on the driving mode.

[0064] In some embodiments, for driving modes with high vehicle stability requirements, such as snow mode, mud mode, and sand mode, the initial torque ratio of the first axle in the corresponding relationship is usually 50% to ensure vehicle stability, and the torque is evenly distributed between the first and second axles. For other driving modes, when the vehicle is traveling at low speeds (e.g., less than 40 kph), the torque ratio of the first axle is usually 50%, and as the vehicle speed increases, the initial torque ratio of the first axle gradually increases, similar to Table 1 above.

[0065] In step 102, the power battery is... Figure 2The power battery 206 shown is equipped with a battery management system in the vehicle to monitor the remaining power of the power battery, and the remaining power of the power battery can be obtained based on the battery management system.

[0066] After obtaining the remaining battery power, the initial torque ratio can be adjusted based on the remaining battery power to obtain the adjusted target torque ratio. The adjustment rule is: the smaller the remaining battery power, the larger the adjusted target torque ratio of the first axle.

[0067] As one implementation method, a correction coefficient can be determined based on the remaining power. The correction coefficient is greater than or equal to 1. The smaller the remaining power, the larger the correction coefficient. The initial torque ratio of the first axle is multiplied by the correction coefficient to obtain the target torque ratio of the first axle.

[0068] For example, if the current remaining battery power is 13%, which is relatively low, the determined correction factor is greater than 1, such as 1.6. If the initial torque percentage of the first axle is 55%, then the target torque percentage of the first axle is 55% * 1.6 = 88%.

[0069] In one possible implementation, the initial torque ratio is corrected based on the remaining power of the power battery to obtain the target torque ratio of the first axle, including: determining the first reference torque ratio of the first axle based on the remaining power and the vehicle speed; wherein, the smaller the remaining power, the larger the first reference torque ratio; and determining the maximum value between the initial torque ratio and the first reference torque ratio as the target torque ratio.

[0070] The vehicle can store a third correspondence between the remaining battery power and vehicle speed, and the proportion of the first reference torque of the first axle. After obtaining the remaining battery power, the current vehicle speed can be obtained. Based on the remaining battery power and vehicle speed, the aforementioned third correspondence is looked up to determine the proportion of the first reference torque. The specific third correspondence is shown in Table 2 below: Table 2

[0071] In the third correspondence shown in Table 2, x represents vehicle speed and s represents remaining battery power, both in percentage. Vehicle speed and remaining battery power correspond to the percentage of the first reference torque of the first axle, also in percentage. In the third correspondence shown in Table 2, when the vehicle speed remains constant, the percentage of the first reference torque of the first axle increases as the remaining battery power decreases. When the remaining battery power remains constant, the percentage of the first reference torque of the first axle increases as the vehicle speed increases.

[0072] It is understood that Table 2 is only one example of the third correspondence, and the proportion of the first reference torque of the first axle can be calibrated according to the actual situation. This application embodiment does not limit this.

[0073] For example, if the remaining battery power is 13% and the vehicle speed is 80 kph, then by looking up Table 2, the first reference torque ratio of the first axle can be determined to be 90%.

[0074] After obtaining the first reference torque percentage of the first axle, the initial torque percentage of the first axle is compared with the first reference torque percentage of the first axle. The maximum value between the initial torque percentage and the first reference torque percentage of the first axle is determined as the target torque percentage of the first axle.

[0075] As in the above embodiment, the initial torque percentage of the first axle is determined to be 55%, and the first reference torque percentage of the first axle is determined to be 90% by referring to Table 2. Since the first reference torque percentage of the first axle is 90% greater than the initial torque percentage of the first axle is 55%, the first reference torque percentage of the first axle can be determined as the target torque percentage of the first axle.

[0076] Understandably, as the remaining battery power decreases, when the battery power is less than a certain value, such as 15%, the vehicle is usually in direct drive four-wheel drive mode. At this time, the engine of the first axle starts and outputs power to drive the vehicle. The higher the proportion of the torque of the first axle, the more torque the engine bears, which can effectively reduce the consumption of the power battery and extend the vehicle's four-wheel drive capability. Therefore, the target torque proportion of the first axle is determined by taking the larger of the initial torque proportion of the first axle and the first reference torque proportion of the first axle.

[0077] In the above method, the first reference torque ratio of the first axle is determined by multiple parameters such as vehicle speed and remaining battery power. The target torque ratio of the first axle is determined by taking the larger of the initial torque ratio and the first reference torque ratio of the first axle. This ensures that the target torque is greater than or equal to the initial torque ratio, thus guaranteeing the effectiveness and reliability of the vehicle's torque distribution. Furthermore, when the first reference torque ratio is greater than the initial torque ratio, the torque ratio of the first axle is effectively increased, ensuring the vehicle's four-wheel drive performance.

[0078] In one possible implementation, before correcting the initial torque ratio based on the remaining charge of the power battery to obtain the target torque ratio of the first axle, the method further includes: obtaining the brake pedal opening and accelerator pedal opening of the vehicle; and determining, based on the brake pedal opening and accelerator pedal opening, that the vehicle is not in a coasting state and is not in a regenerative braking state.

[0079] The vehicle is also equipped with conditions that must be met to correct the initial torque ratio of the first axle based on the remaining battery power. Before correcting the initial torque ratio based on the remaining battery power, it is necessary to determine whether the vehicle meets the conditions. If the vehicle meets the conditions, the initial torque ratio is then corrected based on the remaining battery power.

[0080] Specifically, the vehicle's brake pedal opening and accelerator pedal opening can be obtained, and the vehicle can be judged to be in a coasting state or a brake retraction state based on the brake pedal opening and accelerator pedal opening, thereby determining whether the vehicle meets the above conditions.

[0081] The opening of the brake pedal and the accelerator pedal are usually expressed as a percentage, with a larger percentage indicating a larger opening.

[0082] As one implementation method, it can be determined that the vehicle is in a regenerative braking state when the brake pedal opening is not 0; it can be determined that the vehicle is in a coasting state when both the accelerator pedal opening and the brake pedal opening are 0; and it can be determined that the vehicle is neither in a regenerative braking state nor a coasting state when both the brake pedal opening and the accelerator pedal opening are 0.

[0083] If the vehicle is determined not to be in a coasting state or in a regenerative braking state, and the above conditions are met, the initial torque ratio can be adjusted based on the remaining charge of the power battery. If the vehicle is determined to be in a coasting state or in a regenerative braking state, and the above conditions are not met, then no adjustment is made to the initial torque ratio.

[0084] Understandably, when it's determined that the vehicle is neither in a regenerative braking state nor a coasting state, it can be determined that the vehicle is in a driving state. In this case, the power battery consumes electrical energy to power the first and second motors. Adjusting the initial torque ratio based on the remaining battery charge allows for increased torque on the first axle when the remaining charge is low, thereby increasing the torque borne by the engine and reducing energy consumption. Therefore, when the vehicle is neither in a coasting state nor in a regenerative braking state, the initial torque ratio is adjusted based on the remaining battery charge. When the vehicle is in regenerative braking or coasting regeneration mode, the remaining charge of the power battery is not consumed, and both the first motor on the first axle and the second motor on the second axle can recover energy to generate electricity to recharge the power battery. The engine cannot generate electricity, and therefore does not need to provide additional torque. Consequently, when the vehicle is in regenerative braking or coasting regeneration mode, the initial torque ratio is not adjusted based on the remaining power battery charge.

[0085] In the above method, before correcting the initial torque ratio based on the remaining power of the power battery, it is determined that the vehicle is not in a coasting state or a regenerative braking state based on the opening of the brake pedal and the opening of the accelerator pedal. This can avoid correcting the initial torque ratio of the first axle in the coasting state or the regenerative braking state, which would affect the vehicle's energy recovery logic. This improves the reliability of correcting the initial torque ratio of the first axle based on the remaining power, and thus improves the reliability of the vehicle's torque distribution.

[0086] In one possible implementation, after correcting the initial torque ratio based on the remaining charge of the power battery to obtain the target torque ratio of the first axle, the method further includes: determining whether the vehicle is in a forced charging mode; in the forced charging mode, the engine is forcibly started and the power battery is charged through the first motor; when the vehicle is not in the forced charging mode, the temperature of the first motor is obtained; the target torque ratio is corrected based on the temperature of the first motor to obtain the corrected target torque ratio; wherein, the higher the temperature of the first motor, the smaller the corrected target torque ratio.

[0087] The vehicle can pre-set multiple charging modes for the power battery, such as: efficiency charging mode, enhanced charging mode, and forced charging mode.

[0088] In the efficiency charging mode, the vehicle charges the battery in the most energy-efficient way, typically by utilizing excess kinetic energy or a portion of the engine's power while the engine is running normally. This mode has a lower charging power but minimal impact on fuel economy.

[0089] Enhanced charging mode is a charging strategy between forced charging mode and efficiency charging mode. In enhanced charging mode, the engine is started, and the engine drives the primary electric motor to generate electricity to charge the battery. To replenish the battery faster than efficiency charging mode, enhanced charging mode typically sacrifices some fuel economy, and its charging power is higher than that of efficiency charging mode.

[0090] In forced charging mode, the engine is forcibly started, and the battery is charged via the primary motor. The charging power of the battery via the primary motor is highest in forced charging mode. Forced charging mode is typically activated when the battery has very low remaining charge, such as less than 9%, to quickly restore battery power and ensure the vehicle can continue to operate efficiently. Alternatively, the user can manually activate this mode when they observe that the battery level is low.

[0091] After adjusting the initial torque ratio based on the remaining battery power, it can be determined whether the vehicle is in forced charging mode. If forced charging mode is confirmed, the current temperature of the first motor is obtained, and the target torque ratio is adjusted based on this temperature to obtain the corrected target torque ratio. The vehicle then distributes torque to the first and second axles based on this corrected target torque ratio. If forced charging mode is confirmed, no adjustment is made to the target torque ratio.

[0092] The rule for adjusting the target torque percentage based on the temperature of the first motor is: the higher the temperature of the first motor, the smaller the adjusted target torque percentage.

[0093] Understandably, when the vehicle is not in forced charging mode, the first motor outputs torque to drive the vehicle. If the temperature of the first motor is too high, for example, greater than 130°C, and the first motor continues to output a large torque, there is a risk of overheating and damage to the first motor. In this case, the target torque ratio is adjusted based on the rule that the higher the temperature of the first motor, the smaller the proportion of the corrected target torque. This can effectively reduce the torque output by the first motor and avoid overheating of the first motor.

[0094] Specifically, the vehicle can also store a fourth correspondence between the temperature and speed of the first motor and the fourth reference torque ratio. When it is determined that the vehicle is not in forced charging mode, the temperature and speed of the first motor are acquired, and the fourth correspondence is used to determine the fourth reference torque ratio. The vehicle's fourth correspondence is shown in Table 3 below: Table 3

[0095] In the fourth correspondence shown in Table 3, n represents the rotational speed in rpm (revolutions per minute), and t represents the temperature in °C (degrees Celsius). The rotational speed and temperature correspond to the percentage of the fourth reference torque of the first axle, expressed as a percentage. In the third correspondence shown in Table 3, the percentage of the fourth reference torque decreases with increasing temperature, and vehicle speed has a relatively small impact on the percentage of the fourth reference torque.

[0096] It is understood that Table 3 is only one example of the fourth correspondence, and the proportion of the fourth reference torque of the first axle can be calibrated according to the actual situation, and can also be increased or decreased due to the influence of vehicle speed. This application embodiment does not limit this.

[0097] For example, the temperature of the first motor is 140°C and the speed is 2000 rpm. By referring to Table 3, it can be determined that the proportion of the fourth reference torque is 50%.

[0098] After obtaining the fourth reference torque percentage, the minimum value between the target torque percentage and the fourth reference torque percentage is determined as the corrected target torque percentage. If the corrected target torque percentage is less than or equal to the target torque percentage, the target torque percentage can be reduced based on the temperature of the first motor.

[0099] As in the above embodiment, the target torque percentage is 90%, and the fourth reference torque percentage of the first axle determined by looking up Table 3 is 50%. Since the fourth reference torque percentage of the first axle is 50%, which is less than the target torque percentage of 90%, the fourth reference torque percentage of 50% can be determined as the corrected target torque percentage of the first axle.

[0100] Figure 3This is a flowchart of a method for correcting torque ratio based on remaining battery power, provided in an embodiment of this application.

[0101] For example, such as Figure 3 As shown, the method 300 includes: Step 301: Determine whether coasting or braking is activated; if yes, end; if no, proceed to step 302. Among them, coasting activation means that the vehicle is in a coasting state, and braking activation means that the vehicle is in a regenerative braking state.

[0102] Step 302: Based on the vehicle speed and remaining battery power, correct the initial torque ratio of the first axle to obtain the target torque ratio; The specific correction process is as described in the above embodiment: the first reference torque percentage is determined based on the vehicle speed and the remaining battery power, and the larger of the initial torque percentage and the first reference torque percentage is taken.

[0103] Step 303: Determine if the forced charging mode is activated; if yes, end; if no, proceed to step 304. Step 304: Correct the target torque ratio based on the rotational speed and temperature of the first motor to obtain the corrected target torque ratio.

[0104] The specific correction process is as described in the above embodiment: the fourth reference torque ratio is determined based on the speed and temperature of the first motor, and the smaller of the target torque ratio and the fourth reference torque ratio is taken.

[0105] In the above method, when it is determined that the motor is not in forced charging mode, the target torque ratio is corrected based on the rule that "the higher the temperature of the first motor, the smaller the proportion of the corrected target torque". This can effectively reduce the torque output by the first motor, avoid the first motor from continuing to output a large torque and causing the first motor to overheat, and improve the safety of the first motor.

[0106] In one possible implementation, the first axle includes a first wheel, and the second axle includes a second wheel. After determining the initial torque percentage allocated to the first axle based on the vehicle's drive mode and driving mode, the method further includes: determining a reference speed based on a first average vehicle speed of the first wheel and a second average vehicle speed of the second wheel; determining the slip ratio of the first wheel based on the first average vehicle speed and the reference speed; and determining the slip ratio of the second wheel based on the second average vehicle speed and the reference speed; and correcting the initial torque percentage based on the slip ratio of the first wheel or the slip ratio of the second wheel to obtain the target torque percentage of the first axle.

[0107] The first wheel specifically includes a first left wheel and a first right wheel, and the second wheel specifically includes a second left wheel and a second right wheel. The average speed of the first wheel is the average speed calculated based on the average wheel speeds of the first left wheel and the first right wheel, and the average speed of the second wheel is the average speed calculated based on the average wheel speeds of the second left wheel and the second right wheel.

[0108] When the vehicle is in a driving state, the minimum of the average speeds of the first wheel (V1) and the second wheel (V2) can be determined as the reference speed V, where V = Min(V1, V2). When the vehicle is in a coasting state or a regenerative braking state, the maximum of the average speeds of the first wheel (V1) and the second wheel (V2) can be determined as the reference speed V, where V = Max(V1, V2).

[0109] After obtaining the reference vehicle speed, the slip ratio 'a' of the first wheel and the slip ratio 'b' of the second wheel can be calculated based on the reference vehicle speed. Specifically, the average speed of the first wheel is subtracted from the reference vehicle speed to obtain the first difference. The ratio of the first difference to the reference vehicle speed is determined as the slip ratio 'a' of the first wheel, which is calculated as: slip ratio 'a' = (V1 - V) / V. Similarly, the average speed of the second wheel is subtracted from the reference vehicle speed to obtain the second difference. The ratio of the second difference to the reference vehicle speed is determined as the slip ratio 'b' of the second wheel, which is calculated as: slip ratio 'b' = (V2 - V) / V.

[0110] It is understandable that the reference vehicle speed is a value between the average speed of the first wheel V1 and the average speed of the second wheel V2. Therefore, there is a slip ratio of 0 between the slip ratio of the first wheel a and the slip ratio of the second wheel b.

[0111] For example, V1 = 70 kph, V2 = 50 kph, and the vehicle is currently in a driving state with a reference speed V = Min(V1, V2) = Min(70 kph, 50 kph) = 50 kph. The slip ratio of the first wheel is a = (V1 - V) / V = ​​(70 - 50) / 50 ≈ 0.4. The slip ratio of the second wheel is b = (V2 - V) / V = ​​(50 - 50) / 50 = 0.

[0112] After obtaining the slip ratio of the first wheel and the slip ratio of the second wheel, the initial torque ratio is corrected based on the slip ratio of the first wheel or the slip ratio of the second wheel to obtain the target torque ratio of the first axle.

[0113] In the above method, a reference speed is determined based on the first average speed of the first wheel and the second average speed of the second wheel. Based on this, the slip ratio of the first wheel or the slip ratio of the second wheel is determined. This method can efficiently identify the wheel in the vehicle that is slipping more severely. The initial torque ratio is then corrected based on the slip ratio of the wheel that is slipping more severely to obtain the target torque ratio. This allows the vehicle to reduce slippage after distributing torque based on the target torque ratio, thereby improving the driving safety of the vehicle.

[0114] In one possible implementation, the initial torque ratio is corrected based on the slip ratio of the first wheel or the slip ratio of the second wheel to obtain the target torque ratio of the first axle, including: determining a reference slip ratio based on a reference vehicle speed; if the slip ratio of the first wheel is greater than the reference slip ratio, correcting the initial torque ratio based on the slip ratio of the first wheel to obtain the target torque ratio of the first axle; if the slip ratio of the second wheel is greater than the reference slip ratio, correcting the initial torque ratio based on the slip ratio of the second wheel to obtain the target torque ratio of the first axle.

[0115] The reference slip ratio is the maximum slip ratio when the vehicle is not slipping at the current reference speed. When the slip ratio is greater than the reference slip ratio, it can be determined that the vehicle is slipping.

[0116] Reference slip ratios corresponding to different reference vehicle speeds can be pre-calibrated in the vehicle. After obtaining the reference vehicle speed, the reference slip ratio corresponding to that speed can be determined. For example, in the above embodiment, the reference vehicle speed is 50 kph, and its corresponding reference slip ratio c is assumed to be 0.2.

[0117] After obtaining the reference slip ratio, the slip ratios 'a' of the first wheel and 'b' of the second wheel are determined to be relative to the reference slip ratio. If the slip ratio 'a' of the first wheel is greater than the reference slip ratio 'c', the slip ratio of the first wheel is activated. At this point, the initial torque ratio is adjusted based on the slip ratio of the first wheel to obtain the target torque ratio of the first axle. If the slip ratio 'b' of the second wheel is greater than the reference slip ratio 'c', the slip ratio of the second wheel is activated. At this point, the initial torque ratio is adjusted based on the slip ratio of the second wheel to obtain the target torque ratio of the first axle.

[0118] As in the above embodiment, the slip ratio of the first wheel is a = (V1-V) / V = (70-50) / 50 = 0.4, the slip ratio of the second wheel is b = (V2-V) / V = (50-50) / 50 = 0, and the reference slip ratio is c = 0.2. The slip ratio of the first wheel is a = 0.4, which is greater than the reference slip ratio c = 0.2, and the slip ratio of the second wheel is b = 0, which is less than the reference slip ratio c = 0.2. At this time, the target torque ratio of the first axle is obtained by correcting the initial torque ratio based on the slip ratio a of the first wheel.

[0119] In the above method, the reference slip ratio is determined based on the reference vehicle speed. The torque ratio of the first axle is only corrected based on the slip ratio when the slip ratio is greater than the reference slip ratio. This effectively avoids vehicle slippage and also avoids redundant correction when the slip ratio is small, thus improving the practicality of slip ratio correction.

[0120] In one possible implementation, the initial torque percentage is corrected based on the slip ratio of the first wheel to obtain the target torque percentage of the first axle, including: determining a second reference torque percentage of the first axle based on the slip ratio of the first wheel and the reference vehicle speed; and determining the minimum value between the initial torque percentage and the second reference torque percentage as the target torque percentage.

[0121] The greater the slip ratio of the first wheel, the smaller the proportion of the second reference torque of the first axle.

[0122] Specifically, the vehicle stores a fifth correspondence between two parameters: the slip ratio and reference vehicle speed of the first wheel, and the proportion of the second reference torque of the first axle. This fifth correspondence can be used to determine the proportion of the second reference torque of the first axle by looking up the fifth correspondence based on the slip ratio and reference vehicle speed of the first wheel. The fifth correspondence is shown in Table 4 below. Table 4

[0123] In the fifth correspondence shown in Table 4, 'a' represents the slip ratio of the first wheel, 'v' represents the reference vehicle speed, and the slip ratio of the first wheel and the reference vehicle speed correspond to the percentage of the second reference torque, expressed as a percentage (%). As shown in Table 4, in the fifth correspondence, the percentage of the second reference torque of the first axle is less than 50%. When the slip ratio of the first wheel is greater than the reference slip ratio, the percentage of the second reference torque decreases as the slip ratio of the first wheel increases, until the slip ratio of the first wheel increases to 1, at which point the percentage of the second reference torque decreases to 0. In the fifth correspondence, vehicle speed has a relatively small impact on the percentage of the second reference torque.

[0124] It is understood that Table 4 is only one example of the fifth correspondence, in which the proportion of the second reference torque of the first axle can be calibrated according to the actual situation, and can also be increased or decreased due to the influence of vehicle speed. This application embodiment does not limit this.

[0125] The greater the slip ratio of the first wheel, the more severe the slip of the first wheel. At this time, more torque needs to be transferred to the second axle to prevent the first wheel from slipping. Therefore, in the fifth correspondence, as the slip ratio of the first wheel increases, the proportion of the second reference torque decreases.

[0126] For example, the slip ratio of the first wheel is a = (V1-V) / V = (70-50) / 50 = 0.4, and the reference vehicle speed is V = 50 kph. Then, by referring to Table 4, we can find that the proportion of the second reference torque is 30%.

[0127] After obtaining the second reference torque ratio of the first axle, the minimum value between the initial torque ratio and the second reference torque ratio is determined as the target torque ratio in order to reduce the torque ratio of the first axle.

[0128] It is understandable that the slip ratio 'a' of the first wheel is greater than the reference slip ratio. At this point, it can be determined that the first wheel is slipping. It is necessary to reduce the torque of the first wheel. By reducing the initial torque ratio and the second reference torque ratio, the torque ratio of the first axle can be reduced, thereby reducing the torque of the first wheel and effectively preventing the first wheel from slipping.

[0129] As in the above embodiment, the initial torque percentage is 55%, and the second reference torque percentage is 30%. The second reference torque percentage of 30% is less than the initial torque percentage of 55%. At this time, the second reference torque percentage can be used to determine the target torque percentage, that is, the target torque percentage of the first axle is 30%.

[0130] In the above method, if the slip ratio of the first axle is greater than the reference slip ratio, it can be determined that the first wheel is slipping. By reducing the initial torque ratio and the second reference torque ratio, the torque ratio of the first axle can be reduced, thereby reducing the torque of the first wheel and effectively preventing the first wheel from slipping.

[0131] In one possible implementation, the initial torque percentage is corrected based on the slip ratio of the second wheel to obtain the target torque percentage of the first axle, including: determining the third reference torque percentage of the first axle based on the slip ratio of the second wheel and the reference vehicle speed; and determining the maximum value between the initial torque percentage and the third reference torque percentage as the target torque percentage.

[0132] The greater the slip ratio of the second wheel, the greater the proportion of the third reference torque of the first axle.

[0133] Specifically, the vehicle stores a sixth correspondence between the slip ratio and reference speed of the second wheel and the third reference torque ratio of the first axle. Based on the slip ratio and reference speed of the second wheel, the fifth correspondence can be looked up to determine the third reference torque ratio of the first axle. The sixth correspondence is shown in Table 5 below: Table 5

[0134] In the sixth correspondence shown in Table 5, b represents the slip ratio of the second wheel, v represents the reference vehicle speed, and the slip ratio of the second wheel and the reference vehicle speed correspond to the percentage of the third reference torque, in percentages. As shown in Table 5, in the sixth correspondence, the percentage of the third reference torque of the first axle is greater than 50%; when the reference vehicle speed is fixed, the percentage of the third reference torque increases with the increase of the slip ratio of the second wheel; when the slip ratio of the second wheel is fixed, the percentage of the third reference torque increases with the increase of the reference vehicle speed.

[0135] Understandably, a higher slip ratio of the second wheel indicates more severe wheel slippage. In this case, more torque needs to be transferred to the first axle to prevent the second wheel from slipping. Therefore, in the sixth correspondence, with a fixed reference speed, the proportion of the third reference torque increases as the slip ratio of the second wheel increases. A higher reference speed indicates a higher actual vehicle speed, making the vehicle more prone to slippage. Therefore, in the sixth correspondence, with a fixed slip ratio of the second wheel, the proportion of the third reference torque increases as the reference speed increases.

[0136] It is understood that Table 5 is only one example of the fifth correspondence, and the embodiments of this application do not limit it.

[0137] For example, if the slip ratio of the second wheel is b=0.6 and the reference vehicle speed is V=50kph, then by referring to Table 5, the proportion of the third reference torque can be obtained as 75%.

[0138] After obtaining the third reference torque ratio of the first axle, the maximum value between the initial torque ratio and the third reference torque ratio is determined as the target torque ratio in order to increase the torque ratio of the first axle.

[0139] It is understandable that the slip ratio b of the second wheel is greater than the reference slip ratio. At this time, it can be determined that the second wheel is slipping. It is necessary to reduce the torque of the second wheel. By taking the larger of the initial torque ratio and the third reference torque ratio, the torque ratio of the first axle can be increased, thereby reducing the torque ratio of the second axle. Reducing the torque of the second wheel can effectively prevent the second wheel from slipping.

[0140] As in the above embodiment, the initial torque percentage is 55%, the third reference torque percentage is 75%, and the third reference torque percentage of 75% is greater than the initial torque percentage of 55%. At this time, the third reference torque percentage can be determined as the target torque percentage, that is, the target torque percentage of the first axle is 75%.

[0141] like Figure 2The first axle shown is the front axle, and the first wheels are specifically the front wheels of the vehicle, including the left front wheel 2071 and the right front wheel 2072; the corresponding second wheels are the rear wheels of the vehicle, including the left rear wheel 2081 and the right rear wheel 2082. The slip ratio of the first wheel is the front wheel slip ratio, and the slip ratio of the second wheel is the rear wheel slip ratio. Figure 4 This is a flowchart of a method for correcting torque ratio based on slip ratio provided in an embodiment of this application.

[0142] For example, such as Figure 4 As shown, the method 400 includes: Step 401: Determine if the front wheel slip ratio is active and the rear wheel slip ratio is not active; if yes, proceed to step 402; if no, proceed to step 403.

[0143] Specifically, determining whether the front wheel slip ratio is active and the rear wheel slip ratio is not active means determining that the front wheel slip ratio is greater than the reference slip ratio corresponding to the reference vehicle speed and the rear wheel slip ratio is less than the reference slip ratio.

[0144] Step 402: Correct the initial torque ratio based on the front wheel slip ratio to obtain the target torque ratio.

[0145] The specific correction process is as described in the above embodiment: based on the front wheel slip ratio (i.e., the slip ratio of the first wheel) and the reference vehicle speed, the second reference torque ratio is determined, and the smaller of the initial torque ratio and the second reference torque ratio is taken.

[0146] Step 403: Determine if the rear wheel slip ratio is active and the front wheel slip ratio is not active; if yes, proceed to step 404; otherwise, end.

[0147] Specifically, determining whether the rear wheel slip ratio is active and the front wheel slip ratio is not active means determining whether the rear wheel slip ratio is greater than the reference slip ratio corresponding to the reference vehicle speed and the front wheel slip ratio is less than the reference slip ratio.

[0148] Step 404: Correct the initial torque ratio based on the rear wheel slip ratio to obtain the target torque ratio.

[0149] The specific correction process is as described in the above embodiment: based on the rear wheel slip ratio (i.e., the slip ratio of the second wheel) and the reference vehicle speed, the third reference torque ratio is determined, and the larger of the initial torque ratio and the third reference torque ratio is taken.

[0150] In the above method, when the slip ratio of the second wheel is greater than the reference slip ratio, it can be determined that the second wheel is slipping. By taking the larger of the initial torque ratio of the first axle and the third reference torque ratio, the torque ratio of the first axle can be increased, thereby transferring the torque of the second wheel to the first wheel, thus reducing the torque of the second wheel and effectively preventing the second wheel from slipping.

[0151] In some embodiments, the torque percentage obtained by correcting the initial torque percentage based on the slip ratio of the first wheel or the slip ratio of the second wheel is recorded as an intermediate value, and then the intermediate value is corrected based on the remaining battery power to obtain the target torque percentage.

[0152] In some embodiments, before correcting the initial torque percentage based on the slip ratio, the initial torque percentage can also be corrected based on the slope and steering wheel angle to obtain the corrected initial torque percentage, and then the corrected initial torque percentage is corrected based on the slip ratio.

[0153] The method of correcting the initial torque ratio based on the slope includes: obtaining the slope value of the road where the vehicle is currently located; when the absolute value of the slope value is greater than or equal to a preset value, correcting the initial torque ratio based on the slope value to obtain the first initial torque ratio; wherein, when the first axle is the front axle, the larger the slope value, the smaller the first initial torque ratio.

[0154] The rule for slope correction is as follows: the rear axle torque is higher when going uphill, and the front axle torque is higher when going downhill. A preset value could be, for example, 5°.

[0155] Specifically, the vehicle stores a seventh correspondence between the gradient value and vehicle speed, and the fifth reference torque percentage of the front axle. This seventh correspondence can be used to determine the fifth reference torque percentage of the first axle by looking up the gradient value and vehicle speed. The specific seventh correspondence is shown in Table 6 below: Table 6

[0156] In the seventh correspondence shown in Table 6, x represents vehicle speed, p represents the gradient value (in degrees), and the percentage of the fifth reference torque corresponding to the vehicle speed and gradient value (in percentage). The gradient value can be positive or negative. A positive gradient value indicates the vehicle is going uphill; a negative gradient value indicates the vehicle is going downhill. In the seventh correspondence, when the gradient value is negative, the percentage of the fifth reference torque is greater than 50%; when the gradient is positive, the percentage of the fifth reference torque is less than or equal to 50%. The percentage of the fifth reference torque decreases as the gradient increases. In the seventh correspondence, vehicle speed has a relatively small impact on the percentage of the fifth reference torque.

[0157] like Figure 2 As shown, the first axle is the front axle. After obtaining the fifth reference torque percentage, when the gradient is positive, the minimum value between the initial torque percentage of the first axle and the fifth reference torque percentage is determined as the first initial torque percentage. This reduces the front axle torque and increases the rear axle torque when going uphill. When the gradient is negative, the maximum value between the initial torque percentage of the first axle and the fifth reference torque percentage is determined as the first initial torque percentage. This increases the front axle torque and decreases the rear axle torque when going downhill, thereby increasing the vehicle's climbing ability.

[0158] The initial torque percentage is corrected based on the steering wheel angle, including: obtaining the current steering wheel angle, correcting the first initial torque percentage based on the steering wheel angle, and obtaining the second initial torque percentage (the second initial torque percentage is the corrected initial torque percentage); wherein, the larger the steering wheel angle, the smaller the second initial torque percentage.

[0159] Specifically, the vehicle stores an eighth correspondence between the parameters of steering wheel angle and vehicle speed and the correction coefficient. This eighth correspondence can be used to determine the target correction coefficient, and then the initial torque ratio is adjusted based on this target correction coefficient. The eighth correspondence is shown in Table 7 below. Table 7

[0160] In the eighth correspondence shown in Table 7, x represents vehicle speed, and o represents steering wheel angle, both in degrees. Vehicle speed and steering wheel angle correspond to correction coefficients. In the eighth correspondence, when the vehicle speed is 0 kph, the correction coefficient is 1, meaning no correction is applied when the vehicle speed is 0. When the vehicle speed is greater than 0 kph, the correction coefficient is less than or equal to 1, used to reduce the torque of the first axle. Specifically, when the vehicle speed is greater than 0 kph and the steering wheel angle is less than or equal to 30°, the correction coefficient is 1; when the vehicle speed is greater than 0 kph and the steering wheel angle is greater than 30°, the correction coefficient is less than 1, and the correction coefficient decreases as the steering wheel angle increases.

[0161] After obtaining the correction coefficient, the first initial torque ratio is multiplied by the correction coefficient to obtain the second initial torque ratio, which is the corrected initial torque ratio. This reduces the torque of the first axle when the steering wheel angle is larger, thus ensuring the vehicle's power performance and cornering safety.

[0162] Figure 5 This is a flowchart of the method for correcting torque ratio provided in the embodiments of this application.

[0163] For example, such as Figure 5 As shown, the method 500 includes: Step 501: Determine whether the vehicle's actual driving mode is pure electric front-wheel drive mode or hybrid front-wheel drive mode; if yes, proceed to step 502; if no, proceed to step 503. Step 502, the front axle torque ratio is 100%.

[0164] In pure electric front-wheel drive mode, the front-wheel drive motor is running and outputs power to drive the vehicle, while the rear-wheel drive motor is not working. In hybrid front-wheel drive mode, both the engine and the front-wheel drive motor are running, and the engine and the front-wheel drive motor output power together to drive the vehicle, while the rear-wheel drive motor is not working.

[0165] Step 503: Determine whether the vehicle's actual driving mode is pure electric four-wheel drive mode or direct drive four-wheel drive mode; if yes, proceed to step 504; if no, proceed to step 508. Step 504: Determine the initial torque percentage of the front axle based on the base MAP.

[0166] The basic MAP (Mapping Table) includes: a first correspondence between different driving modes in direct-drive four-wheel drive mode and a second correspondence between different driving modes in pure electric four-wheel drive mode. The process of determining the initial torque ratio based on the first and second correspondences is as described in the above embodiment and will not be repeated here.

[0167] In some embodiments, the basic MAP further includes a ninth correspondence for the regenerative braking state and a tenth correspondence for the coasting state. When it is determined that the vehicle is in the regenerative braking state, the initial torque percentage of the first axle is determined based on the ninth correspondence; when it is determined that the vehicle is in the coasting state, the initial torque percentage of the first axle is determined based on the tenth correspondence.

[0168] The ninth correspondence is the relationship between the actual torque and vehicle speed of the first axle and the initial torque percentage. When the vehicle is in a regenerative braking state, the ninth correspondence can be used to determine the initial torque percentage of the first axle based on the actual torque and vehicle speed of the first axle. The specific details of the ninth correspondence are shown in Table 8 below. Table 8

[0169] In the ninth correspondence shown in Table 8, x is the vehicle speed and y is the actual torque of the first axle. The actual torque of the first axle is always negative. As the actual torque of the first axle increases, the proportion of the initial torque decreases. The maximum proportion of the initial torque is 55% and the minimum is 50%.

[0170] The tenth correspondence includes correspondence 1 for the single-pedal coasting state and correspondence 2 for the normal coasting state. Both correspondence 1 and correspondence 2 are the correspondence between the actual torque and vehicle speed of the first axle and the initial torque ratio. When the vehicle is determined to be in the single-pedal coasting state, the initial torque ratio of the first axle can be determined by looking up correspondence 1 based on the actual torque and vehicle speed of the first axle. When the vehicle is determined to be in the normal coasting state, the initial torque ratio of the first axle can be determined by looking up correspondence 2 based on the actual torque and vehicle speed of the first axle. Correspondence 1 is shown in Table 9 below: Table 9

[0171] In the correspondence shown in Table 9, x is the vehicle speed and y is the actual torque of the first axle. The actual torque of the first axle is always negative. As the actual torque of the first axle increases, the proportion of the initial torque decreases. The maximum proportion of the initial torque is 55% and the minimum is 50%.

[0172] Correspondence 2 is shown in Table 10 below: Table 10

[0173] In the correspondence shown in Table 10, x is the vehicle speed, y is the actual torque of the first axle, the actual torque of the first axle is always negative, and the initial torque ratio is a fixed value of 40%.

[0174] It is understood that Tables 8, 9 and 10 above are merely examples, and the initial torque percentages can be determined according to actual conditions. This application does not limit this.

[0175] Step 505: When slope correction is activated, the corrected initial torque ratio is obtained based on the initial torque ratio corrected by slope correction and the initial torque ratio corrected by steering wheel angle. Step 506: Based on the slip ratio, correct the initial torque ratio after the above correction to obtain the intermediate value; Step 507: Based on the remaining power of the power battery, correct the above intermediate value to obtain the target torque ratio.

[0176] The process of correction based on slip ratio and remaining charge is as described in the above embodiments and will not be repeated here.

[0177] Step 508, the front axle torque ratio is 0%.

[0178] In step 103, after obtaining the target torque ratio, the vehicle's requested torque is determined based on parameters such as the accelerator pedal opening and the current vehicle speed; the vehicle's requested torque is multiplied by the target torque ratio to obtain the torque allocated to the first axle; the vehicle's requested torque is subtracted from the torque allocated to the first axle to obtain the torque allocated to the second axle.

[0179] For example, if the target torque percentage is 75% and the vehicle's requested torque is 1000 Nm, then the torque allocated to the first axle can be calculated as follows: Torque allocated to the first axle = Vehicle requested torque * Target torque percentage = 1000 Nm * 75% = 750 Nm. Torque allocated to the second axle = Vehicle requested torque - Torque allocated to the first axle = 1000 Nm - 750 Nm = 250 Nm.

[0180] Figure 6 This is a schematic diagram of the structure of a torque distribution device provided in an embodiment of this application.

[0181] For example, such as Figure 6 As shown, the device 600 includes: The determining module 601 is used to determine the initial torque ratio allocated to the first axle based on the vehicle's drive mode and driving mode when the vehicle is in four-wheel drive mode; wherein the first axle is equipped with a first motor and an engine. The correction module 602 is used to correct the initial torque ratio based on the remaining power of the power battery to obtain the target torque ratio of the first axle; wherein, the smaller the remaining power, the larger the target torque ratio. The allocation module 603 is used to determine a first target torque allocated to the first axle and a second target torque allocated to the second axle based on the target torque ratio; wherein the second axle is equipped with a second motor.

[0182] In one possible implementation, the correction module 602 is specifically used to: determine the first reference torque ratio of the first axle based on the remaining battery power and the vehicle speed; wherein, the smaller the remaining battery power, the larger the first reference torque ratio; and determine the maximum value between the initial torque ratio and the first reference torque ratio as the target torque ratio.

[0183] In one possible implementation, the correction module 602 is further configured to: after correcting the initial torque ratio based on the remaining charge of the power battery to obtain the target torque ratio of the first axle, determine whether the vehicle is in a forced charging mode; in the forced charging mode, the engine is forcibly started and the power battery is charged through the first motor; when the vehicle is not in the forced charging mode, the temperature of the first motor is obtained; the target torque ratio is corrected based on the temperature of the first motor to obtain the corrected target torque ratio; wherein, the higher the temperature of the first motor, the smaller the corrected target torque ratio.

[0184] In one possible implementation, the determining module 601 is further configured to: obtain the brake pedal opening and accelerator pedal opening of the vehicle before correcting the initial torque ratio based on the remaining power of the power battery to obtain the target torque ratio of the first axle; and determine, based on the brake pedal opening and accelerator pedal opening, that the vehicle is not in a coasting state and is not in a regenerative braking state.

[0185] In one possible implementation, the correction module 602 is further configured to: determine a reference speed based on the first average speed of the first wheel and the second average speed of the second wheel; determine the slip ratio of the first wheel based on the first average speed and the reference speed; determine the slip ratio of the second wheel based on the second average speed and the reference speed; and correct the initial torque ratio based on the slip ratio of the first wheel or the slip ratio of the second wheel to obtain the target torque ratio of the first axle.

[0186] In one possible implementation, the correction module 602 is specifically used to: determine a reference slip ratio based on a reference vehicle speed; if the slip ratio of the first wheel is greater than the reference slip ratio, correct the initial torque ratio based on the slip ratio of the first wheel to obtain the target torque ratio of the first axle; if the slip ratio of the second wheel is greater than the reference slip ratio, correct the initial torque ratio based on the slip ratio of the second wheel to obtain the target torque ratio of the first axle.

[0187] In one possible implementation, the correction module 602 is specifically used to: determine the second reference torque ratio of the first axle based on the slip ratio of the first wheel and the reference vehicle speed; and determine the minimum value between the initial torque ratio and the second reference torque ratio as the target torque ratio.

[0188] In one possible implementation, the correction module 602 is specifically used to: determine the third reference torque ratio of the first axle based on the slip ratio of the second wheel and the reference vehicle speed; and determine the maximum value between the initial torque ratio and the third reference torque ratio as the target torque ratio.

[0189] Figure 7 This is a schematic diagram of the structure of a vehicle provided in an embodiment of this application.

[0190] For example, such as Figure 7 As shown, the vehicle 700 includes a memory 701 and a processor 702. The memory 701 stores executable program code 7011, and the processor 702 is used to call and execute the executable program code 7011 to perform a torque distribution method.

[0191] Furthermore, embodiments of this application also protect an apparatus that may include a memory and a processor, wherein the memory stores executable program code, and the processor is used to call and execute the executable program code to perform a torque distribution method provided in embodiments of this application.

[0192] This embodiment can divide the device into functional modules based on the above method example. For example, each module can correspond to a separate function, or two or more functions can be integrated into one processing module. The integrated module can be implemented in hardware. It should be noted that the module division in this embodiment is illustrative and only represents one logical functional division. In actual implementation, there may be other division methods.

[0193] When each functional module is divided according to its corresponding function, the device may further include a determining module, a correcting module, and an allocating module. It should be noted that all relevant content regarding the steps involved in the above method embodiments can be referenced from the functional descriptions of the corresponding functional modules, and will not be repeated here.

[0194] It should be understood that the device provided in this embodiment is used to execute the torque distribution method described above, and therefore can achieve the same effect as the above implementation method.

[0195] When using an integrated unit, the device may include a processing module and a storage module. When the device is applied to a vehicle, the processing module can be used to control and manage the vehicle's movements. The storage module can be used to support the vehicle in executing relevant program code.

[0196] The processing module may be a processor or a controller, which can implement or execute various exemplary logic blocks, modules, and circuits shown in conjunction with the disclosure of this application. The processor may also be a combination of functions that implement computing capabilities, such as a combination of one or more microprocessors, a combination of digital signal processing (DSP) and a microprocessor, etc., and the storage module may be a memory.

[0197] In addition, the device provided in the embodiments of this application may specifically be a chip, component or module. The chip may include a connected processor and a memory. The memory is used to store instructions. When the processor calls and executes the instructions, the chip can execute a torque distribution method provided in the above embodiments.

[0198] This embodiment also provides a computer-readable storage medium storing computer program code. When the computer program code is run on a computer, the computer executes the above-described related method steps to implement the torque distribution method provided in the above embodiment.

[0199] This embodiment also provides a computer program product that, when run on a computer, causes the computer to perform the aforementioned steps to implement a torque distribution method provided in the above embodiment.

[0200] In this embodiment, the device, computer-readable storage medium, computer program product, or chip are all used to execute the corresponding methods provided above. Therefore, the beneficial effects they can achieve can be referred to the beneficial effects in the corresponding methods provided above, and will not be repeated here.

[0201] Through the above description of the embodiments, those skilled in the art will understand that, for the sake of convenience and brevity, only the division of the above functional modules is used as an example. In actual applications, the above functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above.

[0202] In the embodiments provided in this application, it should be understood that the disclosed apparatus and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of modules or units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another device, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between devices or units may be electrical, mechanical, or other forms.

[0203] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A torque distribution method, characterized in that, The method includes: When the vehicle is in motion, the initial torque percentage allocated to the first axle is determined based on the vehicle's drive mode and driving mode; wherein the first axle is equipped with a first motor and an engine; The initial torque ratio is adjusted based on the remaining charge of the power battery to obtain the target torque ratio of the first axle; wherein, the smaller the remaining charge, the larger the target torque ratio. Based on the target torque ratio, a first target torque to be allocated to the first axle and a second target torque to be allocated to the second axle are determined; wherein, the second axle is equipped with a second motor.

2. The method according to claim 1, characterized in that, The process of correcting the initial torque ratio based on the remaining charge of the power battery to obtain the target torque ratio of the first axle includes: Based on the remaining battery power and the vehicle speed, a first reference torque percentage for the first axle is determined; wherein, the smaller the remaining battery power, the larger the first reference torque percentage. The maximum value between the initial torque percentage and the first reference torque percentage is determined as the target torque percentage.

3. The method according to claim 1 or 2, characterized in that, After correcting the initial torque ratio based on the remaining power of the power battery to obtain the target torque ratio of the first axle, the method further includes: Determine whether the vehicle is in a forced charging mode; in the forced charging mode, the engine is forcibly started and the power battery is charged through the first motor. When the vehicle is not in the forced charging mode, the temperature of the first motor is obtained; The target torque ratio is corrected based on the temperature of the first motor to obtain the corrected target torque ratio; wherein, the higher the temperature of the first motor, the smaller the corrected target torque ratio.

4. The method according to claim 1 or 2, characterized in that, Before correcting the initial torque ratio based on the remaining charge of the power battery to obtain the target torque ratio of the first axle, the method further includes: Obtain the brake pedal opening and accelerator pedal opening of the vehicle; Based on the brake pedal opening and the accelerator pedal opening, it is determined that the vehicle is neither in a coasting state nor in a brake regeneration state.

5. The method according to claim 1 or 2, characterized in that, The first axle includes a first wheel, and the second axle includes a second wheel; after determining the initial torque percentage allocated to the first axle based on the vehicle's drive mode and driving mode, the method further includes: A reference speed is determined based on the first average speed of the first wheel and the second average speed of the second wheel. Based on the first average vehicle speed and the reference vehicle speed, the slip ratio of the first wheel is determined; and based on the second average vehicle speed and the reference vehicle speed, the slip ratio of the second wheel is determined. The initial torque ratio is corrected based on the slip ratio of the first wheel or the slip ratio of the second wheel to obtain the target torque ratio of the first axle.

6. The method according to claim 5, characterized in that, The initial torque ratio is corrected based on the slip ratio of the first wheel or the slip ratio of the second wheel to obtain the target torque ratio of the first axle, including: The reference slip ratio is determined based on the reference vehicle speed; If the slip ratio of the first wheel is greater than the reference slip ratio, the initial torque ratio is corrected based on the slip ratio of the first wheel to obtain the target torque ratio of the first axle. If the slip ratio of the second wheel is greater than the reference slip ratio, the initial torque ratio is corrected based on the slip ratio of the second wheel to obtain the target torque ratio of the first axle.

7. The method according to claim 6, characterized in that, The step of correcting the initial torque ratio based on the slip ratio of the first wheel to obtain the target torque ratio of the first axle includes: Based on the slip ratio of the first wheel and the reference vehicle speed, the second reference torque ratio of the first axle is determined; The minimum value between the initial torque percentage and the second reference torque percentage is determined as the target torque percentage.

8. The method according to claim 6, characterized in that, The step of correcting the initial torque ratio based on the slip ratio of the second wheel to obtain the target torque ratio of the first axle includes: Based on the slip ratio of the second wheel and the reference vehicle speed, the third reference torque ratio of the first axle is determined. The maximum value between the initial torque percentage and the third reference torque percentage is determined as the target torque percentage.

9. A vehicle, characterized in that, The vehicles include: Memory, used to store executable program code; A processor for calling and running the executable program code from the memory, causing the vehicle to perform the method as described in any one of claims 1 to 8.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed, implements the method as described in any one of claims 1 to 8.

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