A method and apparatus for motor torque distribution

Abstract

The application discloses a motor torque distribution method and device. The method comprises the following steps: in the case that a target vehicle reaches a yaw control activation condition, acquiring a current yaw angular velocity corresponding to the target vehicle; determining a first yaw angular velocity based on a linear two-degree-of-freedom vehicle model, and determining a second yaw angular velocity based on a current lateral acceleration, a current vehicle speed, a current steering wheel angle change rate and the current yaw angular velocity corresponding to the target vehicle; determining a target yaw angular velocity based on the first yaw angular velocity and the second yaw angular velocity, and distributing a target motor torque corresponding to the target vehicle based on the target yaw angular velocity and the current yaw angular velocity, so that more accurate torques corresponding to front wheels and rear wheels can be determined, and the torques are distributed to corresponding wheels, so that the vehicle can better maintain lateral stability when steering, especially when oversteering, and the user driving experience is improved.

Description

Technical Field

[0001] This invention relates to the field of electric vehicle technology, and in particular to a method and apparatus for motor torque distribution. Background Technology

[0002] With the development of automotive technology, more and more four-wheel drive electric vehicles are being used by users. Four-wheel drive electric vehicles refer to electric vehicles that can use four-wheel drive during operation. When a four-wheel drive electric vehicle turns, the engagement torque of the transfer case and clutch needs to be adjusted according to the vehicle's condition to achieve a reasonable distribution of drive torque between the front and rear axles, thereby improving the vehicle's handling stability. However, current four-wheel drive control systems cannot effectively adjust the engagement torque of the transfer case and clutch, especially in situations where the distributed drive torque to the rear axle is much greater than that to the front axle. This results in poor steering performance and stability under oversteer conditions, reducing the user's driving experience. Summary of the Invention

[0003] This invention provides a method and apparatus for motor torque distribution, which determines the more accurate torque corresponding to the front and rear wheels and distributes the torque to their respective wheels, thereby enabling the vehicle to maintain better lateral stability during steering, especially oversteering, and improving the user's driving experience.

[0004] According to one aspect of the present invention, a method for distributing motor torque is provided, the method comprising:

[0005] If the target vehicle is detected to have reached the yaw control activation condition, the current yaw rate of the target vehicle is obtained.

[0006] The first yaw rate is determined based on a linear two-degree-of-freedom vehicle model, and the second yaw rate is determined based on the current lateral acceleration, current vehicle speed, current steering wheel angle change rate, and the current yaw rate of the target vehicle.

[0007] Based on the first yaw rate and the second yaw rate, a target yaw rate is determined, and based on the target yaw rate and the current yaw rate, the target motor torque corresponding to the target vehicle is allocated.

[0008] According to another aspect of the present invention, a motor torque distribution device is provided, the device comprising:

[0009] The current yaw rate determination module is used to obtain the current yaw rate of the target vehicle when the target vehicle is detected to have reached the yaw control activation condition.

[0010] The yaw rate determination module is used to determine the first yaw rate based on a linear two-degree-of-freedom vehicle model, and to determine the second yaw rate based on the current lateral acceleration, current vehicle speed, current steering wheel angle change rate and the current yaw rate of the target vehicle.

[0011] The target motor torque distribution module is used to determine a target yaw rate based on the first yaw rate and the second yaw rate, and to distribute the target motor torque corresponding to the target vehicle based on the target yaw rate and the current yaw rate.

[0012] The technical solution of this invention involves obtaining the current yaw rate of the target vehicle when the target vehicle reaches the yaw control activation condition; determining a first yaw rate based on a linear two-degree-of-freedom vehicle model; determining a second yaw rate based on the target vehicle's current lateral acceleration, current vehicle speed, current steering wheel angle change rate, and the current yaw rate; determining a target yaw rate based on the first and second yaw rates, thereby identifying the yaw rate with the smallest variation as the target yaw rate; and allocating the target motor torque corresponding to the target vehicle based on the target yaw rate and the current yaw rate. This more accurately determines the torque corresponding to the front and rear wheels and distributes the torque to their respective wheels, thereby enabling the vehicle to maintain better lateral stability during steering, especially oversteering, and improving the user's driving experience.

[0013] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of the present invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0014] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0015] Figure 1 This is a flowchart of a motor torque distribution method provided according to Embodiment 1 of the present invention;

[0016] Figure 2 This is a flowchart of a motor torque distribution method provided according to Embodiment 2 of the present invention;

[0017] Figure 3 This is a flowchart of a motor torque distribution method provided according to Embodiment 3 of the present invention;

[0018] Figure 4 This is a schematic diagram of the structure of a motor torque distribution device according to Embodiment 4 of the present invention;

[0019] Figure 5 This is a schematic diagram of the structure of an electronic device that implements the motor torque distribution method of this invention. Detailed Implementation

[0020] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0021] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0022] Example 1

[0023] Figure 1 This is a flowchart of a motor torque distribution method provided in Embodiment 1 of the present invention. This embodiment is applicable to situations where torque is distributed between the motors corresponding to the front wheels and the motors corresponding to the rear wheels when the vehicle reaches the yaw control activation condition. This method can be executed by a motor torque distribution device, which can be implemented in hardware and / or software and can be configured in an electronic device. Figure 1 As shown, the method includes:

[0024] S110. When the target vehicle is detected to have reached the yaw control activation condition, obtain the current yaw rate of the target vehicle.

[0025] The target vehicle can be, but is not limited to, sedans and commercial vehicles. The yaw control activation condition refers to the prerequisites that must be met to activate the yaw control function. The yaw rate can refer to the angular velocity of the vehicle's mass rotating around the z-axis (the coordinate axis perpendicular to the ground). The current yaw rate can refer to the yaw rate of the target vehicle at the current moment.

[0026] Specifically, if the target vehicle reaches the yaw control activation condition during normal driving, the current yaw rate of the target vehicle is obtained based on the angular velocity sensor.

[0027] For example, the yaw control activation conditions include at least one of the following conditions: the target vehicle's driving mode is in four-wheel drive mode; the target vehicle's current speed is greater than or equal to a preset speed; the target vehicle's vehicle stability function is inactive; the target vehicle's current steering wheel angle is not less than a preset steering wheel angle or the current steering wheel angle change rate is not less than a preset steering wheel angle change rate; the target vehicle's current motor torque is greater than or equal to a preset torque threshold; the target vehicle's current required target motor torque is greater than or equal to a preset required total torque threshold.

[0028] Among them, Electronic Stabilization Program (ESP) is the function performed by the vehicle's electronic stability system. Yaw control is activated if all activation conditions are met. This setup avoids issues such as reduced driving experience and vehicle safety caused by the yaw control function not being activated or deactivated in a timely manner during low speeds, small steering angles, or situations requiring ESP intervention due to vehicle loss of control.

[0029] S120. Determine the first yaw rate based on the linear two-degree-of-freedom vehicle model, and determine the second yaw rate based on the target vehicle's current lateral acceleration, current vehicle speed, current steering wheel angle change rate, and current yaw rate.

[0030] In this context, the linear two-degree-of-freedom vehicle model can refer to a pre-built vehicle model that simulates the forces acting on the vehicle during steering. Lateral acceleration can refer to the acceleration of the vehicle perpendicular to the direction of motion.

[0031] Specifically, a linear two-degree-of-freedom vehicle model can predict the first yaw rate based on current vehicle information. Based on the current lateral acceleration of the target vehicle, a first weight corresponding to the current lateral acceleration is determined. Based on the current vehicle speed, a second weight corresponding to the current vehicle speed is determined. Based on the current rate of change of steering wheel angle, a third weight corresponding to the current rate of change of steering wheel angle is determined. Based on the first, second, and third weights and the current yaw rate, the second yaw rate corresponding to the target vehicle is determined. For example, the first, second, and third weights can be multiplied by the current yaw rate, and the result can be used to determine the second yaw rate corresponding to the target vehicle.

[0032] S130. Based on the first yaw rate and the second yaw rate, determine the target yaw rate, and based on the target yaw rate and the current yaw rate, allocate the target motor torque corresponding to the target vehicle.

[0033] The target yaw rate refers to the yaw rate that the vehicle needs to achieve. When the vehicle reaches the target yaw rate, it smoothly completes the steering maneuver. The target motor torque refers to the motor torque required for the vehicle to reach the target yaw rate from its current yaw rate. Both the first and second yaw rates can ensure that the vehicle can complete the steering without overturning.

[0034] Specifically, a target yaw rate is determined based on a first yaw rate and a second yaw rate. For example, the first yaw rate and the second yaw rate are compared, and the smaller yaw rate is determined as the target yaw rate. The angular velocity difference between the target yaw rate and the current yaw rate is determined, and the required torque for the motors corresponding to the front and rear wheels of the target vehicle is determined based on the angular velocity difference. For example, the torque distribution ratio for the front and rear wheels of the target vehicle is determined based on the angular velocity difference and a pre-calibrated proportional coefficient, and the target motor torque for the target vehicle is then allocated.

[0035] The technical solution of this invention involves obtaining the current yaw rate of the target vehicle when the target vehicle reaches the yaw control activation condition; determining a first yaw rate based on a linear two-degree-of-freedom vehicle model; determining a second yaw rate based on the target vehicle's current lateral acceleration, current vehicle speed, current steering wheel angle change rate, and current yaw rate; determining a target yaw rate based on the first and second yaw rates, thus identifying the yaw rate with the smallest variation as the target yaw rate; and allocating the target motor torque corresponding to the target vehicle based on the target yaw rate and the current yaw rate, thereby more accurately determining the torque corresponding to the front and rear wheels and distributing the torque to their respective wheels. This allows the vehicle to maintain better lateral stability during steering, especially oversteering, improving the user's driving experience.

[0036] Based on the above technical solution, the "determining the first yaw rate based on a linear two-degree-of-freedom vehicle model" in S120 may include: obtaining the current front wheel angle and current vehicle speed of the target vehicle; inputting the pre-calibrated wheelbase and stability factor, the current front wheel angle and current vehicle speed of the target vehicle into the linear two-degree-of-freedom vehicle model; and obtaining the first yaw rate based on the output of the linear two-degree-of-freedom vehicle model.

[0037] Specifically, in a linear two-degree-of-freedom vehicle model, the formula for determining the first yaw rate is as follows:

[0038]

[0039] Where, ω r δ is the first yaw rate, δ is the current front wheel steering angle, u is the current vehicle speed, L is the vehicle's wheelbase, and K is the stability factor.

[0040] Based on the above technical solution, S130's "determining the target yaw rate based on the first yaw rate and the second yaw rate" can include: if the first yaw rate is less than or equal to the second yaw rate, then the first yaw rate is determined as the target yaw rate; if the first yaw rate is greater than the second yaw rate, then the second yaw rate is determined as the target yaw rate. The advantage of this setting is that although both the first and second yaw rates can complete the steering, a yaw rate closer to the current yaw rate allows for smoother steering, preventing significant body tilting of occupants during steering. Furthermore, by comparing the magnitudes of the first and second yaw rates, the target yaw rate for yaw control can be reasonably distinguished between three operating conditions: neutral steering, minor oversteer / understeer, and significant oversteer / understeer. This further accurately identifies the yaw rate corresponding to the vehicle's loss of control boundary, preventing loss of vehicle control due to an excessively large target yaw rate.

[0041] It's important to clarify that neutral steering, oversteer, and understeer refer to the steering characteristics of a vehicle under different driving conditions. Neutral steering means the vehicle's turning radius remains constant, which can be understood as the vehicle's pure rolling state in reality. Understeer means the vehicle's turning radius gradually increases; it can be understood as a vehicle that "rolls outward" when turning, or requiring more steering angle input than expected to maintain the desired turning radius. Oversteer means the vehicle's turning radius gradually decreases; it can be understood as a vehicle that "spins in place" when turning, or the driver has to reduce the steering angle input to keep the vehicle following the desired path.

[0042] Example 2

[0043] Figure 2 This is a flowchart of a motor torque distribution method provided in Embodiment 2 of the present invention. Based on the above embodiments, this embodiment describes in detail the process of determining the second yaw rate. Explanations of terms that are the same as or corresponding to those in the above embodiments are not repeated here. Figure 2 As shown, the method includes:

[0044] S210. When the target vehicle is detected to have reached the yaw control activation condition, obtain the current yaw rate of the target vehicle.

[0045] S220. The first yaw rate is determined based on a linear two-degree-of-freedom vehicle model.

[0046] S230. Determine the first angular velocity coefficient based on the current yaw rate, current lateral acceleration, and current vehicle speed.

[0047] The first angular velocity coefficient can refer to one of the weights used to determine the additional yaw rate. The additional yaw rate can refer to the yaw rate that needs to be added to the current yaw rate. Specifically, the weight used to determine the additional yaw rate can be determined based on the current yaw rate, the current lateral acceleration, and the current vehicle speed, and this weight is defined as the first angular velocity coefficient.

[0048] S240. Based on the pre-calibrated second correspondence between vehicle speed and angular velocity coefficient and the current vehicle speed, determine the second angular velocity coefficient.

[0049] The second correspondence can refer to the pre-calibrated correspondence between vehicle speed and angular velocity coefficient. The second angular velocity coefficient can be one of the weights used to determine the additional yaw rate. Specifically, based on the pre-calibrated second correspondence between vehicle speed and angular velocity coefficient and the current vehicle speed, a second angular velocity coefficient corresponding to the current vehicle speed is determined.

[0050] S250. Based on the pre-calibrated third correspondence between the steering wheel angle change rate and the angular velocity coefficient, and the current steering wheel angle change rate, determine the third angular velocity coefficient.

[0051] The third correspondence can refer to the pre-calibrated correspondence between the steering wheel angle change rate and the angular velocity coefficient. The third angular velocity coefficient can be one of the weights used to determine the additional yaw rate. Specifically, based on the pre-calibrated third correspondence between the steering wheel angle change rate and the angular velocity coefficient, the current steering wheel angle change rate is matched to determine the third angular velocity coefficient that matches the current steering wheel angle change rate.

[0052] S260. Determine the additional yaw rate based on the first angular velocity coefficient, the second angular velocity coefficient, the third angular velocity coefficient, and the current yaw rate.

[0053] Specifically, the first angular velocity coefficient, the second angular velocity coefficient, the third angular velocity coefficient, and the current yaw rate are multiplied together, and the result of the multiplication is determined as the additional yaw rate corresponding to the target vehicle.

[0054] S270. Add the additional yaw rate and the current yaw rate together, and determine the result as the second yaw rate.

[0055] S280. Based on the first yaw rate and the second yaw rate, determine the target yaw rate, and based on the target yaw rate and the current yaw rate, allocate the target motor torque corresponding to the target vehicle.

[0056] The technical solution of this invention determines a first angular velocity coefficient based on the current yaw rate, current lateral acceleration, and current vehicle speed; a second angular velocity coefficient based on a pre-calibrated second correspondence between vehicle speed and angular velocity coefficients and the current vehicle speed; a third angular velocity coefficient based on a pre-calibrated third correspondence between steering wheel angle change rate and angular velocity coefficients and the current steering wheel angle change rate; and an additional yaw rate is determined based on the first, second, and third angular velocity coefficients and the current yaw rate. Thus, based on the current yaw rate, current lateral acceleration, current vehicle speed, and current steering wheel angle change rate, a comprehensive determination is made of the additional yaw rate required for the current yaw rate. The additional yaw rate is calculated by adding the additional yaw rate to the current yaw rate and determining the result as the second yaw rate. Based on the second yaw rate determined by the comprehensive calculation and the first yaw rate output by the model, the target yaw rate can be determined. The yaw rate with the smallest change is then determined as the target yaw rate. Based on the target yaw rate and the current yaw rate, the target motor torque corresponding to the target vehicle is allocated. This further determines the torque corresponding to the front and rear wheels more accurately and distributes the torque to their respective wheels. It also enables the vehicle to maintain better lateral stability during steering, especially oversteering, thus improving the user's driving experience.

[0057] Based on the above technical solution, S230 may include: dividing the current lateral acceleration by the current vehicle speed to obtain the division result; subtracting the current yaw rate from the division result and using the subtraction result as the speed difference; and determining the first angular velocity coefficient based on the first correspondence between the pre-calibrated speed difference and the angular velocity coefficient and the speed difference.

[0058] Wherein, "vehicle speed difference" = ("current yaw rate" - "current lateral acceleration" / "current vehicle speed"). The first correspondence can refer to the pre-calibrated correspondence between the speed difference and the angular velocity coefficient. The first angular velocity coefficient can refer to one of the weights used to determine the additional yaw rate.

[0059] Example 3

[0060] Figure 3 This is a flowchart of a motor torque distribution method provided in Embodiment 3 of the present invention. This embodiment describes in detail the process of distributing the target motor torque based on the above embodiments. Explanations of terms that are the same as or corresponding to those in the above embodiments are not repeated here. Figure 3 As shown, the method includes:

[0061] S310. When the target vehicle is detected to have reached the yaw control activation condition, obtain the current yaw rate of the target vehicle.

[0062] S320. The first yaw rate is determined based on a linear two-degree-of-freedom vehicle model, and the second yaw rate is determined based on the target vehicle's current lateral acceleration, current vehicle speed, current steering wheel angle change rate, and current yaw rate.

[0063] S330. Determine the target yaw rate based on the first yaw rate and the second yaw rate.

[0064] S340. Based on the target yaw rate and the current yaw rate, determine the target torque distribution coefficient corresponding to the target vehicle.

[0065] Specifically, the current yaw rate can be divided by the target yaw rate, and the result can be compared with a preset threshold. If the result is greater than or equal to the preset threshold, the target torque distribution coefficient for the target vehicle is determined based on the current yaw rate, the target yaw rate, a pre-calibrated first proportional coefficient, and the current torque distribution coefficient. If the result is less than the preset threshold, the target torque distribution coefficient for the target vehicle is determined based on the current yaw rate, the target yaw rate, a pre-calibrated second proportional coefficient, and the current torque distribution coefficient. For example, the preset threshold could be 0.5, the first proportional coefficient could be 1, and the second proportional coefficient could be 2.

[0066] S350: Based on the target torque distribution coefficient, the target motor torque required by the target vehicle is distributed to the front and rear wheels of the target vehicle.

[0067] Specifically, based on the target torque distribution coefficient and the target motor torque, the rear wheel torque corresponding to the rear wheel of the target vehicle is determined, and the rear wheel torque is distributed to the rear wheel of the target vehicle, while the remaining torque is distributed to the front wheel of the target vehicle.

[0068] It should be noted that when the determined torque distribution coefficient exceeds the effective range, the boundary torque distribution coefficient corresponding to the effective range boundary can be used as the target torque distribution coefficient for the target vehicle. Based on the target torque distribution coefficient, the target motor torque required by the target vehicle is distributed to the front and rear wheels of the target vehicle. This limits the effective range of the target torque distribution coefficient for the target vehicle determined based on the target yaw rate and the current yaw rate, i.e., upper and lower threshold limits. Then, the motor torque corresponding to the front and rear wheel motors is adjusted to avoid drivability problems caused by excessive changes in the torque of the front and rear axles.

[0069] The technical solution of this invention determines the target torque distribution coefficient corresponding to the target vehicle based on the target yaw rate and the current yaw rate; based on the target torque distribution coefficient, the target motor torque required by the target vehicle is distributed to the front and rear wheels of the target vehicle, further determining the accurate torque corresponding to each of the front and rear wheels, and distributing the torque to their corresponding wheels. This enables the vehicle to maintain better lateral stability when steering, especially during oversteering, thus improving the user's driving experience.

[0070] Based on the above technical solution, S340 may include: subtracting the target yaw rate from the current yaw rate to obtain the subtraction result; multiplying the subtraction result with a pre-calibrated proportional coefficient to obtain the multiplication result; adding the multiplication result to the current torque distribution coefficient, and determining the addition result as the target torque distribution coefficient corresponding to the target vehicle; wherein, the proportional coefficient is related to the vehicle speed of the target vehicle and the difference between the target yaw rate and the current yaw rate.

[0071] Specifically, the target yaw rate is subtracted from the current yaw rate. The subtraction result is then divided by the current yaw rate. The result is then evaluated. Continuing with the previous example, if the result is greater than or equal to a preset threshold, the subtraction result is multiplied by a second proportional coefficient, and the multiplication result is added to the current torque distribution coefficient. This sum is then determined as the target torque distribution coefficient for the target vehicle. If the result is less than the preset threshold, the subtraction result is multiplied by a first proportional coefficient, and the multiplication result is added to the current torque distribution coefficient. This sum is then determined as the target torque distribution coefficient for the target vehicle.

[0072] Based on the above technical solution, S350 may include: multiplying the target torque distribution coefficient by the target motor torque corresponding to the target vehicle to obtain the rear wheel torque corresponding to the rear wheel of the target vehicle, and distributing the rear wheel torque to the rear wheel of the target vehicle; subtracting the target motor torque from the rear wheel torque to obtain the front wheel torque corresponding to the front wheel of the target vehicle, and distributing the front wheel torque to the front wheel of the target vehicle.

[0073] Specifically, the target torque distribution coefficient is multiplied by the target motor torque corresponding to the target vehicle to obtain the rear wheel torque of the target vehicle. This determined rear wheel torque is then transmitted via a communication line to the controller corresponding to the motor controlling the rear wheels of the target vehicle, enabling the controller to perform torque control on the rear wheels based on the received torque. The target motor torque is subtracted from the rear wheel torque to obtain the front wheel torque of the target vehicle. This determined front wheel torque is then transmitted via a communication line to the controller corresponding to the motor controlling the front wheels of the target vehicle, enabling the controller to perform torque control on the front wheels based on the received front wheel torque. This achieves simultaneous torque control on both the front and rear wheels of the target vehicle, further enhancing lateral stability during steering, especially oversteering, and improving the user's driving experience.

[0074] The following are embodiments of the motor torque distribution device provided in this invention. This device and the motor torque distribution methods in the above embodiments belong to the same inventive concept. For details not described in detail in the embodiments of the motor torque distribution device, please refer to the embodiments of the above motor torque distribution methods.

[0075] Example 4

[0076] Figure 4 This is a schematic diagram of a motor torque distribution device provided in Embodiment 4 of the present invention. Figure 4 As shown, the device includes: a current yaw rate determination module 410, a yaw rate determination module 420, and a target motor torque distribution module 430.

[0077] The current yaw rate determination module 410 is used to obtain the current yaw rate of the target vehicle when the target vehicle is detected to have reached the yaw control activation condition; the yaw rate determination module 420 is used to determine the first yaw rate based on the linear two-degree-of-freedom vehicle model, and to determine the second yaw rate based on the current lateral acceleration, current vehicle speed, current steering wheel angle change rate and current yaw rate of the target vehicle; the target motor torque distribution module 430 is used to determine the target yaw rate based on the first yaw rate and the second yaw rate, and to distribute the target motor torque of the target vehicle based on the target yaw rate and the current yaw rate.

[0078] The technical solution of this invention involves obtaining the current yaw rate of the target vehicle when the target vehicle reaches the yaw control activation condition; determining a first yaw rate based on a linear two-degree-of-freedom vehicle model; determining a second yaw rate based on the target vehicle's current lateral acceleration, current vehicle speed, current steering wheel angle change rate, and current yaw rate; determining a target yaw rate based on the first and second yaw rates, thus identifying the yaw rate with the smallest variation as the target yaw rate; and allocating the target motor torque corresponding to the target vehicle based on the target yaw rate and the current yaw rate, thereby more accurately determining the torque corresponding to the front and rear wheels and distributing the torque to their respective wheels. This allows the vehicle to maintain better lateral stability during steering, especially oversteering, improving the user's driving experience.

[0079] Optionally, the yaw rate determination module 420 may include:

[0080] The first angular velocity coefficient determination submodule is used to determine the first angular velocity coefficient based on the current yaw rate, current lateral acceleration, and current vehicle speed.

[0081] The second angular velocity coefficient determination submodule is used to determine the second angular velocity coefficient based on the pre-calibrated second correspondence between vehicle speed and angular velocity coefficient and the current vehicle speed;

[0082] The third angular velocity coefficient determination submodule is used to determine the third angular velocity coefficient based on the pre-calibrated third correspondence between the steering wheel angle change rate and the angular velocity coefficient and the current steering wheel angle change rate.

[0083] An additional yaw rate determination submodule is used to determine the additional yaw rate based on the first angular velocity coefficient, the second angular velocity coefficient, the third angular velocity coefficient, and the current yaw rate.

[0084] The second yaw rate determination submodule is used to add the additional yaw rate and the current yaw rate, and determine the result as the second yaw rate.

[0085] Optionally, the first angular velocity coefficient determination submodule is specifically used to: divide the current lateral acceleration by the current vehicle speed to obtain the division result; subtract the current yaw rate from the division result and use the subtraction result as the speed difference; and determine the first angular velocity coefficient based on the first correspondence between the pre-calibrated speed difference and the angular velocity coefficient and the speed difference.

[0086] Optionally, the target motor torque distribution module 430 may include:

[0087] The first target yaw rate determination submodule is used to determine the first yaw rate as the target yaw rate if the first yaw rate is less than or equal to the second yaw rate.

[0088] The second target yaw rate determination submodule is used to determine the second yaw rate as the target yaw rate if the first yaw rate is greater than the second yaw rate.

[0089] Optionally, the target motor torque distribution module 430 may include:

[0090] The torque distribution coefficient determination submodule is used to determine the target torque distribution coefficient corresponding to the target vehicle based on the target yaw rate and the current yaw rate.

[0091] The target motor torque distribution submodule is used to distribute the target motor torque required by the target vehicle to the front and rear wheels of the target vehicle based on the target torque distribution coefficient.

[0092] Optionally, the torque distribution coefficient determination submodule is specifically used to: subtract the target yaw rate from the current yaw rate to obtain the subtraction result; multiply the subtraction result with a pre-calibrated proportional coefficient to obtain the multiplication result; add the multiplication result to the current torque distribution coefficient, and determine the addition result as the target torque distribution coefficient corresponding to the target vehicle; wherein, the proportional coefficient is related to the vehicle speed of the target vehicle and the difference between the target yaw rate and the current yaw rate.

[0093] Optionally, the target motor torque distribution submodule is specifically used to: multiply the target torque distribution coefficient by the target motor torque corresponding to the target vehicle to obtain the rear wheel torque corresponding to the rear wheel of the target vehicle, and distribute the rear wheel torque to the rear wheel of the target vehicle; subtract the target motor torque from the rear wheel torque to obtain the front wheel torque corresponding to the front wheel of the target vehicle, and distribute the front wheel torque to the front wheel of the target vehicle.

[0094] Optionally, the yaw rate determination module 420 is specifically used to: obtain the current front wheel angle and current vehicle speed of the target vehicle; input the pre-calibrated wheelbase and stability factor, current front wheel angle and current vehicle speed of the target vehicle into the linear two-degree-of-freedom vehicle model; and obtain the first yaw rate based on the output of the linear two-degree-of-freedom vehicle model.

[0095] Optionally, the yaw control activation conditions include at least one of the following conditions: the target vehicle's driving mode is in four-wheel drive mode; the target vehicle's current speed is greater than or equal to a preset speed; the target vehicle's vehicle stability function is inactive; the target vehicle's current steering wheel angle is not less than a preset steering wheel angle or the current steering wheel angle change rate is not less than a preset steering wheel angle change rate; the target vehicle's current motor torque is greater than or equal to a preset torque threshold; the target vehicle's current required target motor torque is greater than or equal to a preset required total torque threshold.

[0096] The motor torque distribution device provided in the embodiments of the present invention can execute the motor torque distribution method provided in any embodiment of the present invention, and has the corresponding functional modules and beneficial effects for executing the motor torque distribution method.

[0097] It is worth noting that in the embodiments of the motor torque distribution device described above, the various units and modules included are only divided according to functional logic, but are not limited to the above division, as long as the corresponding functions can be achieved; in addition, the specific names of each functional unit are only for easy differentiation and are not used to limit the scope of protection of the present invention.

[0098] Example 5

[0099] Figure 5 A schematic diagram of an electronic device 10 that can be used to implement embodiments of the present invention is shown. The electronic device is intended to represent various forms of digital computers, such as laptop computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The electronic device can also represent various forms of mobile devices, such as personal digital processors, cellular phones, smartphones, wearable devices (e.g., helmets, glasses, watches, etc.), and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely illustrative and are not intended to limit the implementation of the invention described and / or claimed herein.

[0100] like Figure 5As shown, the electronic device 10 includes at least one processor 11 and a memory, such as a read-only memory (ROM) 12 or a random access memory (RAM) 13, communicatively connected to the at least one processor 11. The memory stores computer programs executable by the at least one processor. The processor 11 can perform various appropriate actions and processes based on the computer program stored in the ROM 12 or loaded from storage unit 18 into the RAM 13. The RAM 13 may also store various programs and data required for the operation of the electronic device 10. The processor 11, ROM 12, and RAM 13 are interconnected via a bus 14. An input / output (I / O) interface 15 is also connected to the bus 14.

[0101] Multiple components in electronic device 10 are connected to I / O interface 15, including: input unit 16, such as keyboard, mouse, etc.; output unit 17, such as various types of displays, speakers, etc.; storage unit 18, such as disk, optical disk, etc.; and communication unit 19, such as network card, modem, wireless transceiver, etc. Communication unit 19 allows electronic device 10 to exchange information / data with other devices through computer networks such as the Internet and / or various telecommunications networks.

[0102] Processor 11 can be a variety of general-purpose and / or special-purpose processing components with processing and computing capabilities. Some examples of processor 11 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various special-purpose artificial intelligence (AI) computing chips, various processors running machine learning model algorithms, a digital signal processor (DSP), and any suitable processor, controller, microcontroller, etc. Processor 11 performs the various methods and processes described above, such as motor torque distribution methods.

[0103] In some embodiments, the motor torque distribution method may be implemented as a computer program tangibly contained in a computer-readable storage medium, such as storage unit 18. In some embodiments, part or all of the computer program may be loaded and / or installed on electronic device 10 via ROM 12 and / or communication unit 19. When the computer program is loaded into RAM 13 and executed by processor 11, one or more steps of the motor torque distribution method described above may be performed. Alternatively, in other embodiments, processor 11 may be configured to perform the motor torque distribution method by any other suitable means (e.g., by means of firmware).

[0104] Various embodiments of the systems and techniques described above herein can be implemented in digital electronic circuit systems, integrated circuit systems, field-programmable gate arrays (FPGAs), application-specific integrated circuits (ASICs), application-specific standard products (ASSPs), systems-on-a-chip (SoCs), payload-programmable logic devices (CPLDs), computer hardware, firmware, software, and / or combinations thereof. These various embodiments may include implementations in one or more computer programs that can be executed and / or interpreted on a programmable system including at least one programmable processor, which may be a dedicated or general-purpose programmable processor, capable of receiving data and instructions from a storage system, at least one input device, and at least one output device, and transmitting data and instructions to the storage system, the at least one input device, and the at least one output device.

[0105] Computer programs used to implement the methods of the present invention may be written in any combination of one or more programming languages. These computer programs may be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device, such that when executed by the processor, the computer programs cause the functions / operations specified in the flowcharts and / or block diagrams to be performed. The computer programs may be executed entirely on a machine, partially on a machine, or as a standalone software package, partially on a machine and partially on a remote machine, or entirely on a remote machine or server.

[0106] In the context of this invention, a computer-readable storage medium can be a tangible medium that may contain or store a computer program for use by or in conjunction with an instruction execution system, apparatus, or device. A computer-readable storage medium may include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatus, or devices, or any suitable combination thereof. Alternatively, a computer-readable storage medium may be a machine-readable signal medium. More specific examples of machine-readable storage media include electrical connections based on one or more wires, portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fibers, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof.

[0107] To provide interaction with a user, the systems and techniques described herein can be implemented on an electronic device having: a display device (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor) for displaying information to the user; and a keyboard and pointing device (e.g., a mouse or trackball) through which the user provides input to the electronic device. Other types of devices can also be used to provide interaction with the user; for example, feedback provided to the user can be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user can be received in any form (including sound input, voice input, or tactile input).

[0108] The systems and technologies described herein can be implemented in computing systems that include backend components (e.g., as data servers), or computing systems that include middleware components (e.g., application servers), or computing systems that include frontend components (e.g., user computers with graphical user interfaces or web browsers through which users can interact with implementations of the systems and technologies described herein), or any combination of such backend, middleware, or frontend components. The components of the system can be interconnected via digital data communication of any form or medium (e.g., communication networks). Examples of communication networks include local area networks (LANs), wide area networks (WANs), blockchain networks, and the Internet.

[0109] A computing system can include clients and servers. Clients and servers are generally located far apart and typically interact through communication networks. The client-server relationship is created by computer programs running on the respective computers and having a client-server relationship with each other. The server can be a cloud server, also known as a cloud computing server or cloud host, which is a hosting product within the cloud computing service system to address the shortcomings of traditional physical hosts and VPS services, such as high management difficulty and weak business scalability.

[0110] It should be understood that the various forms of processes shown above can be used, with steps reordered, added, or deleted. For example, the steps described in this invention can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this invention can be achieved, and this is not limited herein.

[0111] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A method of motor torque distribution, characterized by, The method comprises the following steps: In the case of detecting that the target vehicle reaches a yaw control activation condition, obtaining a current yaw angular velocity corresponding to the target vehicle; Determining a first yaw angular velocity based on a linear two-degree-of-freedom vehicle model, and determining a second yaw angular velocity based on a current lateral acceleration, a current vehicle speed, a current steering wheel angle change rate and the current yaw angular velocity corresponding to the target vehicle; Based on the first yaw angular velocity and the second yaw angular velocity, determining a target yaw angular velocity, and based on the target yaw angular velocity and the current yaw angular velocity, distributing a target motor torque corresponding to the target vehicle; The method comprises the following steps: Based on the current yaw angular velocity, the current lateral acceleration and the current vehicle speed, determining a first angular velocity coefficient; Based on a second corresponding relationship between a vehicle speed and an angular velocity coefficient and the current vehicle speed, determining a second angular velocity coefficient; Based on a third corresponding relationship between a steering wheel angle change rate and an angular velocity coefficient and the current steering wheel angle change rate, determining a third angular velocity coefficient; Based on the first angular velocity coefficient, the second angular velocity coefficient, the third angular velocity coefficient and the current yaw angular velocity, determining an additional yaw angular velocity; Adding the additional yaw angular velocity and the current yaw angular velocity, and determining the addition result as the second yaw angular velocity.

2. The method of claim 1, wherein, The method comprises the following steps: Dividing the current lateral acceleration by the current vehicle speed to obtain a division result; Subtracting the current yaw angular velocity from the division result to obtain a speed difference value; Based on a first corresponding relationship between a speed difference value and an angular velocity coefficient and the speed difference value, determining a first angular velocity coefficient.

3. The method of claim 1, wherein, The method comprises the following steps: If the first yaw angular velocity is less than or equal to the second yaw angular velocity, determining the first yaw angular velocity as the target yaw angular velocity; If the first yaw angular velocity is greater than the second yaw angular velocity, determining the second yaw angular velocity as the target yaw angular velocity.

4. The method of claim 1, wherein, The method comprises the following steps: Based on the target yaw angular velocity and the current yaw angular velocity, determining a target torque distribution coefficient corresponding to the target vehicle; Based on the target torque distribution coefficient, distributing a target motor torque required by the target vehicle to front wheels and rear wheels of the target vehicle.

5. The method of claim 4, wherein, The method comprises the following steps: Subtracting the target yaw angular velocity from the current yaw angular velocity to obtain a subtraction result; Multiplying the subtraction result by a pre-labeled proportion coefficient to obtain a multiplication result; Add the multiplication result to the current torque distribution coefficient, and determine the addition result as the target torque distribution coefficient corresponding to the target vehicle; wherein the proportional coefficient is associated with the target vehicle speed and the difference between the target yaw rate and the current yaw rate.

6. The method of claim 4, wherein, The target motor torque required by the target vehicle is distributed to the front wheel and the rear wheel of the target vehicle based on the target torque distribution coefficient, including: The target torque distribution coefficient is multiplied by the target motor torque corresponding to the target vehicle to obtain a rear wheel torque corresponding to the rear wheel of the target vehicle, and the rear wheel torque is distributed to the rear wheel of the target vehicle; The target motor torque is subtracted from the rear wheel torque to obtain a front wheel torque corresponding to the front wheel of the target vehicle, and the front wheel torque is distributed to the front wheel of the target vehicle.

7. The method of claim 1, wherein, The first yaw rate is determined based on the linear two-degree-of-freedom vehicle model, including: Obtaining the current front wheel steering angle and the current vehicle speed corresponding to the target vehicle; The pre-calibrated wheelbase, the stability factor, the current front wheel steering angle and the current vehicle speed corresponding to the target vehicle are input into the linear two-degree-of-freedom vehicle model; The first yaw rate is obtained based on the output of the linear two-degree-of-freedom vehicle model.

8. The method of claim 1, wherein, The yaw control activation condition includes at least one of the following conditions: The vehicle driving mode of the target vehicle is in four-wheel drive mode; The current vehicle speed of the target vehicle is greater than or equal to the preset vehicle speed; The body stability function state of the target vehicle is inactivated; The current steering wheel steering angle of the target vehicle is not less than the preset steering wheel steering angle or the current steering wheel steering angle change rate is not less than the preset steering wheel steering angle change rate; The current motor torque of the target vehicle is greater than or equal to the preset torque threshold; The target motor torque currently required by the target vehicle is greater than or equal to the preset total torque threshold.

9. An electric machine torque distribution device, characterized in that It includes: A current yaw rate determination module for obtaining a current yaw rate corresponding to a target vehicle when it is detected that the target vehicle meets a yaw control activation condition; A yaw rate determination module for determining a first yaw rate based on a linear two-degree-of-freedom vehicle model, and determining a second yaw rate based on the current lateral acceleration, the current vehicle speed, the current steering wheel steering angle change rate and the current yaw rate corresponding to the target vehicle; A target motor torque distribution module for determining a target yaw rate based on the first yaw rate and the second yaw rate, and distributing a target motor torque corresponding to the target vehicle based on the target yaw rate and the current yaw rate; The yaw rate determination module includes: A first angular velocity coefficient determination sub-module for determining a first angular velocity coefficient based on the current yaw rate, the current lateral acceleration and the current vehicle speed; A second angular velocity coefficient determination sub-module for determining a second angular velocity coefficient based on a second corresponding relationship between the pre-calibrated vehicle speed and the angular velocity coefficient and the current vehicle speed; a third angular velocity coefficient determination submodule configured to determine a third angular velocity coefficient based on a third corresponding relationship between the steering wheel angular change rate and the angular velocity coefficient determined in advance and the current steering wheel angular change rate; an additional yaw angular velocity determination submodule configured to determine an additional yaw angular velocity based on the first angular velocity coefficient, the second angular velocity coefficient, the third angular velocity coefficient, and the current yaw angular velocity; a second yaw angular velocity determination submodule configured to add the additional yaw angular velocity and the current yaw angular velocity, and determine a second yaw angular velocity based on the addition result.

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