Torque distribution method, device, controller, vehicle and medium

Abstract

The application discloses a torque distribution method, device, controller, vehicle and medium, and the method comprises the following steps: determining a target demand feedback torque according to a deceleration signal of a vehicle; when a vehicle battery is in a feedback charging power limited state, determining a target torque distribution type with the lowest overall feedback efficiency; and performing a torque distribution operation according to the target torque distribution type and the target demand feedback torque. The application reduces the feedback power for charging the vehicle battery, effectively alleviates the risk of overcharging of the battery due to the limitation of the maximum allowed charging power of the battery, prolongs the service life of the brake disc, and improves the braking safety.

Description

Technical Field

[0001] This invention relates to the field of motor torque distribution technology, and more particularly to a torque distribution method, device, controller, vehicle, and medium. Background Technology

[0002] The motor regenerative torque distribution schemes in related technologies often prioritize vehicle economy while ensuring overall vehicle stability, selecting the most efficient regenerative torque distribution scheme to improve kinetic energy recovery efficiency to a certain extent. However, the drawback of the above scheme is that in certain operating conditions, such as low temperature or fully charged conditions where the battery's charging power is limited, if the most efficient torque distribution scheme is selected, it means that at a certain vehicle speed, the same wheel-end regenerative torque requires a larger regenerative power. Thus, the larger regenerative power will conflict with the battery's limited charging power, easily leading to battery overcharging. Summary of the Invention

[0003] This invention provides a torque distribution method, device, controller, vehicle, and medium to solve problems such as battery overcharging when the battery's allowable charging power is limited in the prior art.

[0004] A torque distribution method, comprising:

[0005] The target required feedback torque is determined based on the vehicle's deceleration signal;

[0006] When the vehicle battery is in a state of limited regenerative charging power, determine the target torque distribution type with the lowest overall regenerative efficiency;

[0007] The torque distribution operation is performed based on the target torque distribution type and the target demand feedback torque.

[0008] A torque distribution device, comprising:

[0009] The first determining module is used to determine the target required feedback torque based on the vehicle's deceleration signal;

[0010] The second determining module is used to determine the target torque distribution type with the lowest overall feedback efficiency when the vehicle battery is in a state of limited feedback charging power.

[0011] The allocation module is used to perform torque allocation operations based on the target torque allocation type and the target demand feedback torque.

[0012] A controller for performing the torque distribution method described above.

[0013] A vehicle including the aforementioned controller.

[0014] A computer readable storage medium stores a computer program, and the computer program is executed by a processor to implement the torque distribution method.

[0015] The torque distribution method, device, controller, vehicle and medium, the method comprises: determining a target demand feedback torque according to a deceleration signal of the vehicle; when the vehicle battery is in a feedback charging power limited state, determining a target torque distribution type with the lowest overall feedback efficiency; and performing a torque distribution operation according to the target torque distribution type and the target demand feedback torque.

[0016] In the present application, the wheel end feedback torque required for vehicle deceleration (i.e., the target demand feedback torque) is first determined, and then when the vehicle battery is in a feedback charging power limited state (i.e., the maximum allowable charging power of the vehicle battery is limited), the target torque distribution type with the lowest overall feedback efficiency is determined, and then reasonable torque distribution operation is performed according to the target torque distribution type and the target demand feedback torque. In this way, under the condition that the wheel end feedback torque required for vehicle deceleration (i.e., the target demand feedback torque) is certain, the feedback power used to charge the vehicle battery is reduced as much as possible, thereby effectively alleviating the risk of overcharging of the battery due to the limitation of the maximum allowable charging power of the battery, prolonging the service life of the brake disc, and improving the braking safety. BRIEF DESCRIPTION OF DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the description of the embodiments of the present application. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0018] Figure 1 is a flowchart of the torque distribution method in an embodiment of the present application;

[0019] Figure 2 is a structural schematic diagram of a vehicle in an embodiment of the present application;

[0020] Figure 3 is a motor speed-torque-efficiency diagram in an embodiment of the present application;

[0021] Figure 4 is a schematic diagram of a torque distribution device in an embodiment of the present application;

[0022] Figure 5 is a schematic diagram of a computer device in an embodiment of the present application. DETAILED DESCRIPTION

[0023] With reference to the accompanying drawings, the technical solutions in the embodiments of the present application will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all the other embodiments obtained by those skilled in the art without creative efforts belong to the scope of the present application.

[0024] The vehicle in the present application can refer to the vehicle shown in Figure 2 The vehicle includes a controller for performing the torque distribution method of the present application; further, the controller includes Figure 2 MCU (Motor Control Unit, vehicle control unit) 1, MCU 2 and MCU 3 shown in Figure 2 MCU 1 is the electronic control of the generator (i.e. ISG, Integrated Starter Generator, integrated intelligent start driving generator) shown in Figure 2 The generator ISG is mechanically connected with the engine; MCU 2 is the two-in-one electronic control of the right front motor (FR_MOT) shown in Figure 2 and the left front motor (FL_MOT) shown in Figure 2 MCU 3 is the two-in-one electronic control of the right rear motor (RR_MOT) shown in Figure 2 and the left rear motor (RL_MOT) shown in The three electronic controls (MCU 1, MCU 2 and MCU 3) included in the above controller can be combined or decomposed according to actual application. The first locking mechanism 11 is used to lock or unlock the power coupling relationship of the associated right front motor (FR_MOT) and left front motor (FL_MOT); the second locking mechanism 12 is used to lock or unlock the power coupling relationship of the associated right rear motor (RR_MOT) and left rear motor (RL_MOT); and the first locking mechanism 11 and the second locking mechanism 12 are controlled by a low-voltage motor (not shown in the figure). The first locking mechanism 11 and the second locking mechanism 12 can be a differential lock.

[0025] Figure 1 In an embodiment, as shown in

[0026] S10: determining a target demand feedback torque according to a deceleration signal of the vehicle. Understandably, when the vehicle is decelerating, if it enters the feedback working condition, it can be indicated that the vehicle can perform energy recovery operation to obtain recovered energy, and then the recovered energy is used to charge the vehicle battery (such as the power battery 13 shown in Figure 2 Understandably, if the vehicle is at the current vehicle speed, Figure 2The four driving motors (right front motor, left front motor, right rear motor, and left rear motor) of the vehicle shown in the middle have the same rotational speed, and if a throttle release or brake pedal depression action occurs at this time, the vehicle receives a deceleration signal, which includes a specific throttle depth change value corresponding to the throttle release or a brake depth change value corresponding to the brake pedal depression, i.e., the deceleration signal contains a target speed to which the vehicle needs to be reduced from the current speed. At this time, in this embodiment, since the current speed of the vehicle and the deceleration signal have been determined, the wheel end feedback torque required for the deceleration process corresponding to the deceleration signal of the vehicle (i.e., the target demand feedback torque) is also certain. In this embodiment, since the current speed of the vehicle can be directly obtained by the controller of the vehicle, and the deceleration signal of the vehicle has been determined, the wheel end feedback torque required for the deceleration process of the vehicle (i.e., the target demand feedback torque) is certain, and at this time, the target demand feedback torque can be calculated according to the current speed and the deceleration signal.

[0027] S20: determining a target torque distribution type with the lowest overall feedback efficiency when the vehicle battery is in a feedback charging power limited state. In this step, the vehicle battery being in a feedback charging power limited state means that the current allowed feedback charging power of the vehicle battery is limited, and when the vehicle is in the feedback charging power limited state, if the target demand feedback torque corresponding to the energy recovery operation of the vehicle is too large, it will cause the risk of overcharging of the battery.

[0028] Specifically, in an embodiment, the feedback charging power limited state includes that the maximum allowed charging power of the vehicle battery is less than or equal to a preset power value. In this embodiment, if it is needed to determine whether the vehicle battery is in a feedback charging power limited state, after a deceleration signal is detected during vehicle driving, it is first needed to determine whether the vehicle battery allows feedback power (i.e., allowed feedback charging power), if the vehicle battery allows feedback power, it can be considered that the vehicle enters a feedback working condition, and then after the maximum allowed charging power (i.e., the maximum allowed charging power of the vehicle battery) of the vehicle battery is obtained, when the maximum allowed charging power is less than or equal to the preset power value, it can be determined that the vehicle battery is in a feedback charging power limited state. Understandably, if no deceleration signal is detected during vehicle driving, or if a deceleration signal is detected during vehicle driving but the vehicle does not enter a feedback working condition, or if a deceleration signal is detected during vehicle driving and the vehicle enters a feedback working condition but the maximum allowed charging power is greater than the preset power value, it can be determined that the vehicle battery is not in a feedback charging power limited state, and at this time, the torque distribution method of the present application does not need to be used for further torque distribution, but returns to step S10.

[0029] In another embodiment, the feedback charging power limited state comprises: a current SOC (State of Charge) value of the vehicle battery exceeds a preset SOC threshold. That is, in this embodiment, only the current SOC value of the vehicle battery needs to be directly obtained by the controller of the vehicle, and then it is determined whether the current SOC value exceeds the preset SOC threshold. When the current SOC value exceeds the preset SOC threshold, it indicates that the current allowable feedback charging power of the vehicle battery is limited. If the charging power for charging the battery converted from the target demand feedback torque when the vehicle performs energy recovery operation is too large, it will cause risks such as overcharging of the battery. At this time, it is determined that the vehicle battery is in a feedback charging power limited state. When the current SOC value does not exceed the preset SOC threshold, it indicates that the current allowable feedback charging power of the vehicle battery has not been limited. At this time, it is determined that the vehicle battery is not in a feedback charging power limited state, and there is no need to use the torque distribution method of the application for further torque distribution, and it returns to step S10.

[0030] In this embodiment, it is necessary to determine a target torque distribution type with the lowest overall feedback efficiency, so that the vehicle performs torque distribution operation through the above-mentioned target torque distribution type with the lowest overall feedback efficiency under the condition that the current vehicle speed is certain when the deceleration signal is received, and then obtains a minimum feedback power corresponding to the target torque distribution type with the lowest overall feedback efficiency under the condition that the target demand feedback torque required by vehicle deceleration is certain, and then charges the vehicle battery through the minimum feedback power. In this way, the feedback power for charging the vehicle battery is reduced as much as possible, thereby effectively alleviating the risks such as overcharging of the battery due to the limitation of the maximum allowable charging power of the battery, prolonging the service life of the brake disc, and improving the braking safety.

[0031] In an embodiment, in step S20, the determination of the target torque distribution type with the lowest overall feedback efficiency comprises:

[0032] According to the current vehicle speed, the target torque distribution type with the lowest overall feedback efficiency is determined from the preset distribution types. That is, when the vehicle battery is in a feedback charging power limited state, the current vehicle speed needs to be obtained first, and then the target torque distribution type with the lowest overall feedback efficiency is determined from different preset distribution types according to the current vehicle speed.

[0033] Understandably, the preset distribution types include but are not limited to one or more of front and rear axle common distribution, front and rear axle mutual resistance distribution, single axle mutual resistance distribution, etc. For example, all target demand feedback torques can be distributed to one of the four driving motors (only through the driving motor to recover torque), and at this time, the torque distribution type is single motor feedback.

[0034] The front-rear axle mutual offset distribution refers to that a first feedback torque is distributed to the target feedback axle (the sum of the feedback torques of the two motors corresponding to the target feedback axle is the first feedback torque), and a first drive torque is distributed to the target drive axle (the sum of the drive torques of the two motors corresponding to the target drive axle is the first drive torque); the difference between the first feedback torque and the first drive torque is equal to the target demand feedback torque. The target feedback axle is the front axle or the rear axle of the vehicle; the target drive axle is the other axle of the front axle and the rear axle except the target feedback axle. Understandably, when the torque is distributed through the front-rear axle mutual offset distribution, the first locking mechanism and the second locking mechanism of the vehicle need to be unlocked, so that the vehicle speeds corresponding to the two motors on the same axle (the target feedback axle or the target drive axle) are the same.

[0035] The front-rear axle mutual offset distribution refers to that a first feedback torque is distributed to the target feedback axle (the sum of the feedback torques of the two motors corresponding to the target feedback axle is the first feedback torque), and a first drive torque is distributed to the target drive axle (the sum of the drive torques of the two motors corresponding to the target drive axle is the first drive torque); the difference between the first feedback torque and the first drive torque is equal to the target demand feedback torque. The target feedback axle is the front axle or the rear axle of the vehicle; the target drive axle is the other axle of the front axle and the rear axle except the target feedback axle. Understandably, when the torque is distributed through the front-rear axle mutual offset distribution, the first locking mechanism and the second locking mechanism of the vehicle need to be unlocked, so that the vehicle speeds corresponding to the two motors on the same axle (the target feedback axle or the target drive axle) are the same.

[0036] The single axle mutual offset distribution refers to that a fourth feedback torque and a second drive torque are respectively distributed to the two motors connected with the target locking mechanism; the difference between the fourth feedback torque and the second drive torque is equal to the target demand feedback torque; the target locking mechanism is the first locking mechanism or the second locking mechanism; the first locking mechanism is connected between the left front motor and the right front motor having a power coupling relationship; the first locking mechanism is used to unlock or lock the power coupling relationship between the left front motor and the right front motor of the front axle. The second locking mechanism is connected between the left rear motor and the right rear motor having a power coupling relationship; the second locking mechanism is used to unlock or lock the power coupling relationship between the left rear motor and the right rear motor of the rear axle. Understandably, when the torque is distributed through the single axle mutual offset distribution, the target locking mechanism of the vehicle needs to be locked, so that the vehicle speeds corresponding to the two motors connected with the target locking mechanism can be different.

[0037] In an aspect of the embodiment, when the current vehicle speed is less than or equal to the preset vehicle speed, the preset distribution types include at least two of the front-rear axle common distribution, the front-rear axle mutual resistance distribution, and the single axle mutual resistance distribution. That is, referring to the above, among the three modes of the front-rear axle common distribution, the front-rear axle mutual resistance distribution, and the single axle mutual resistance distribution, the front-rear axle common distribution and the front-rear axle mutual resistance distribution both require the first locking mechanism and the second locking mechanism to be in the unlocked state, while the single axle mutual resistance distribution can have the rear axle locked. And when the current vehicle speed is less than or equal to the preset vehicle speed, it means that the current vehicle speed is low, at this time the second locking mechanism 12 corresponding to the rear axle can be locked, therefore, in this case, the three modes of the front-rear axle common distribution, the front-rear axle mutual resistance distribution, and the single axle mutual resistance distribution can be compared as the preset distribution types, and then the target torque distribution type with the lowest overall feedback efficiency is determined from the three.

[0038] In another aspect of the embodiment, when the current vehicle speed is greater than the preset vehicle speed, the preset distribution types include the front-rear axle common distribution and the front-rear axle mutual resistance distribution. That is, when the current vehicle speed is greater than the preset vehicle speed, it means that the current vehicle speed is too high, and when the vehicle turns, it is easy to lose stability, therefore, in this case, the rear axle locking should be avoided, and since the single axle mutual resistance distribution can have the rear axle locked, in this embodiment, when the current vehicle speed is greater than the preset vehicle speed, only the front-rear axle common distribution and the front-rear axle mutual resistance distribution are allowed to determine the target torque distribution type with the lowest overall feedback efficiency from the two preset distribution types.

[0039] In an embodiment, the target torque distribution type with the lowest overall feedback efficiency is determined from the preset distribution types according to the current vehicle speed, including:

[0040] According to the preset calibration efficiency parameter, the predicted feedback efficiency value corresponding to each of the preset distribution types at the current vehicle speed is determined. Understandably, the preset calibration efficiency parameter refers to the parameter related to the efficiency of each preset distribution type corresponding to the motor speed-torque-efficiency map. And the motor speed-torque-efficiency map (such as Figure 3The motor speed-torque-efficiency diagram shown can be obtained through offline calibration combined with real vehicle verification; therefore, the preset calibration efficiency parameters can be pre-calibrated based on the aforementioned motor speed-torque-efficiency diagram and each preset allocation type. In this embodiment, the predicted feedback efficiency value corresponding to each preset allocation type can be obtained from the motor speed-torque-efficiency diagram; each predicted feedback efficiency value refers to the feedback efficiency value corresponding to the current vehicle speed and one of the preset allocation types in the motor speed-torque-efficiency diagram; that is, in this embodiment, after the current vehicle speed and the target required feedback torque have been determined, it is necessary to obtain the target torque allocation type with the worst overall feedback efficiency through offline calibration analysis, and then apply the target torque allocation type in the vehicle. Specifically, the aforementioned motor speed-torque-efficiency diagram can be obtained through offline calibration combined with real-vehicle verification. The diagram clearly shows the feedback efficiency values ​​corresponding to different preset allocation types and different feedback torques at any vehicle speed (or motor speed, which is proportional to vehicle speed). This data is presented as curves in a coordinate system within the diagram. Therefore, in this embodiment, only the vehicle's current speed (used to match the vehicle speed or motor speed in the motor speed-torque-efficiency diagram) and the target required feedback torque (used to match the feedback torque in the diagram) need to be determined to determine the predicted feedback efficiency values ​​(comprehensive feedback efficiency) corresponding to different preset allocation types. Understandably, this motor speed-torque-efficiency diagram can be an efficiency diagram, a vehicle speed-torque diagram, etc., corresponding to the vehicle's four drive motors (right front motor, left front motor, right rear motor, and left rear motor).

[0041] The preset allocation type corresponding to the minimum predicted feedback efficiency value is determined as the target torque allocation type. For example, such as... Figure 3 The diagram shown illustrates the torque versus speed output of a single drive motor (i.e., the efficiency diagram). Figure 3 The solid line loop (the loop marked T2) is used to characterize the equivalent loop corresponding to the torque distribution operation when the preset distribution type is shared between the front and rear axles; while Figure 3 The dashed loop (the dashed ring marked T1) is used to characterize the equivalent loop corresponding to this torque distribution type (single-motor feedback) when all target demand feedback torque is distributed to one of the four drive motors. For example... Figure 3As shown in the above embodiment, when the driving motor corresponds to the speed n1 at the current vehicle speed, the single motor feedback corresponds to the wheel end feedback torque T1 which is four times of the wheel end torque T2 distributed by the front and rear axle common distribution (assuming that the front and rear axle common distribution is the state of the target demand feedback torque being evenly distributed between the front and rear axle). That is, T1 = 4*T2. And for the entire controller of the vehicle, the single motor feedback corresponds to the predicted feedback efficiency value (comprehensive feedback efficiency) η1, and the front and rear axle common distribution corresponds to the predicted feedback efficiency value (comprehensive feedback efficiency) η2, and η1>η2; therefore, if the preset distribution type is only the single motor feedback and the above front and rear axle common distribution, the preset distribution type corresponding to the minimum predicted feedback efficiency value is the front and rear axle common distribution, and at this time, the front and rear axle common distribution is the target torque distribution type.

[0042] As can be understood, in the above embodiment, the feedback power of the electric control output end corresponding to the single motor feedback is P1 = η1*(T1*n1) / 9550, and the feedback power of the electric control output end corresponding to the front and rear axle common distribution is P2 = η2*(4*T1*n1) / 9550; therefore, since η1>η2, P1>P2. Therefore, under the condition that the wheel end feedback torque required during the vehicle deceleration (that is, the target demand feedback torque required by the entire wheel end is T1) is certain, compared with the single motor feedback mode (the predicted feedback efficiency value corresponding to the single motor feedback mode is larger, the feedback efficiency is high, and the economy is best), the feedback power of the feedback to the vehicle battery for charging will be smaller by the torque distribution operation through the front and rear axle common distribution, so as to achieve the purpose of protecting the battery and reducing the risk of overcharging.

[0043] In this embodiment, since the preset distribution type includes but is not limited to the front and rear axle common distribution, the front and rear axle mutual resistance distribution, the single axle mutual resistance distribution, etc., in fact, before determining the target torque distribution type, the selectable type of the preset distribution type needs to be determined first, and then determined therefrom. For example, if the preset distribution type includes the front and rear axle common distribution, the front and rear axle mutual resistance distribution and the single axle mutual resistance distribution, and the preset distribution type corresponding to the minimum predicted feedback efficiency value is the single axle mutual resistance distribution, at this time, the single axle mutual resistance distribution is the target torque distribution type. And if the preset distribution type includes the front and rear axle common distribution and the front and rear axle mutual resistance distribution, and the preset distribution type corresponding to the minimum predicted feedback efficiency value is the front and rear axle mutual resistance distribution, at this time, the front and rear axle mutual resistance distribution is the target torque distribution type.

[0044] Understandably, with reference to the above, if the vehicle battery allows a certain feedback power, according to the current vehicle speed and the battery allowed feedback power, the overall feedback efficiency of the target torque distribution type with the lowest target demand feedback torque can be determined from the preset distribution type, and then the torque distribution is performed according to the target torque distribution type, so that greater wheel end feedback torque (target demand feedback torque) can be obtained, and greater deceleration can be obtained.

[0045] S30: Perform torque distribution operation according to the target torque distribution type and the target demand feedback torque. That is, after the target torque distribution type is determined, the torque distribution operation is performed according to the target torque distribution type, so that the overall wheel end feedback torque of the vehicle is equal to the target demand feedback torque.

[0046] In the above embodiment of the application, the wheel end feedback torque required for vehicle deceleration (i.e. target demand feedback torque) is first determined, and then when the vehicle battery is in a feedback charging power limited state (i.e. the maximum allowed charging power of the vehicle battery is limited), the target torque distribution type with the lowest overall feedback efficiency is determined according to the above target demand feedback torque and the current vehicle speed, and then reasonable torque distribution operation is performed according to the target torque distribution type and the target demand feedback torque. In this way, under the condition that the wheel end feedback torque required for vehicle deceleration (i.e. target demand feedback torque) is certain, the feedback power used to charge the vehicle battery is reduced as much as possible, thereby effectively alleviating the risk of overcharging the battery due to the limitation of the maximum allowed charging power of the battery, prolonging the service life of the brake disc, and improving the braking safety.

[0047] Understandably, when the deceleration signal is detected during the above vehicle driving process, if it is confirmed that the vehicle enters the feedback working condition and the whole vehicle is still in series power generation, the vehicle engine will output a certain power generation power to charge the vehicle battery; at this time, if it is further determined that the maximum allowed charging power of the battery is less than or equal to a preset power value, i.e. the allowed charging power of the battery is limited, the series power generation power will be reduced first, and the feedback power of the motor will be preferentially responded, i.e. the power generation power will be attenuated, and the feedback demand will be preferentially met; therefore, the present scheme is also applicable to four-motor independent drive pure electric vehicles.

[0048] It is understandable that the above-mentioned torque distribution method needs to be implemented on the basis of meeting the thermal management (because the relative loss will be relatively large in response to the demand for braking with the lowest overall feedback efficiency, at this time it will be consumed in a more heat-producing manner, which increases the burden of thermal management, so it needs to be considered to be implemented on the basis of meeting the thermal management load). Further, the torque distribution method further comprises: when it is detected that the vehicle is in unstable slip (when the coaxial wheel speed difference or the four-wheel wheel speed difference exceeds a certain threshold, it can be determined that the vehicle is in unstable slip, and the above-mentioned threshold can be set according to the demand), the above-mentioned torque distribution method will be exited, and the above-mentioned deceleration signal will be responded according to a preset deceleration strategy, and the above-mentioned preset deceleration strategy is tested and set for the condition that the vehicle is in unstable slip, which will not be described here.

[0049] In an embodiment, the step S30, that is, the torque distribution operation according to the target torque distribution type and the target demand feedback torque, comprises:

[0050] When the target torque distribution type is the front-rear axle mutual resistance distribution, a first feedback torque is distributed to the target feedback axle, and a first drive torque is distributed to the target drive axle; the difference between the first feedback torque and the first drive torque is equal to the target demand feedback torque; the target feedback axle is the front axle or the rear axle of the vehicle; and the target drive axle is the other axle except the target feedback axle among the front axle and the rear axle. In this embodiment, when the vehicle battery is in a feedback charging power limited state, if it is determined that the target torque distribution type with the lowest overall feedback efficiency is the front-rear axle mutual resistance distribution, at this time, a first feedback torque (the sum of the feedback torques of the two motors corresponding to the target feedback axle is the first feedback torque) is distributed to the target feedback axle, and a first drive torque (the sum of the drive torques of the two motors corresponding to the target drive axle is the first drive torque) is distributed to the target drive axle.

[0051] It is understandable that the difference between the first feedback torque and the first drive torque (that is, the target demand feedback torque) cannot be too large, and needs to be less than a preset front-rear torque difference, so as to avoid vehicle instability; it is understandable that the above-mentioned preset front-rear torque difference can be set according to the bearing capacity of the hardware corresponding to the target feedback axle and the target drive axle after the reverse torques output by the first locking mechanism and the second locking mechanism are unlocked.

[0052] In this embodiment, it is assumed that the front axle is the target drive axle, the first drive torque Tf is allocated, the corresponding equivalent front axle conversion efficiency is ηf, the rear axle is the target feedback axle, the first feedback torque Tr is allocated, and the corresponding equivalent conversion efficiency is ηr; and the target required feedback torque T1 = Tr-Tf; then the feedback power Prf for charging the battery obtained by the vehicle through energy recovery operation is Prf = (-Tf*n1) / (9550*ηf)+ηr*Tr*n1 / 9550; at the same time, Tr-Tf = T1 ≤ A (A is a preset front-rear torque difference) needs to be met to avoid instability. Understandably, it is assumed that the rear axle is the target drive axle and the front axle is the target feedback axle, and the same reasoning applies, which will not be repeated here.

[0053] Further, the step S40, i.e., the torque distribution operation according to the target torque distribution type and the target required feedback torque, further includes:

[0054] The first locking mechanism and the second locking mechanism of the vehicle are controlled to be unlocked, and the allocated torque of the axle corresponding to each of the locking mechanisms is evenly distributed to each motor of the axle. The first locking mechanism is used to unlock or lock the power coupling relationship between the left front motor and the right front motor of the front axle; and the second locking mechanism is used to unlock or lock the power coupling relationship between the left rear motor and the right rear motor of the rear axle. Specifically, when the target torque distribution type is front-rear axle common distribution, the first locking mechanism and the second locking mechanism of the vehicle need to be controlled to be unlocked, so that the two motors on the same axle (target feedback axle or target drive axle) have the same corresponding vehicle speed.

[0055] In an embodiment, the step S30, i.e., the torque distribution operation according to the target torque distribution type and the target required feedback torque, includes:

[0056] In the case that the target torque distribution type is front-rear axle common distribution, a second feedback torque is distributed to the first feedback axle, and a third feedback torque is distributed to the second feedback axle; the sum of the second feedback torque and the third feedback torque is equal to the target demand feedback torque; the first feedback axle is the front axle or the rear axle of the vehicle; the second feedback axle is the other axle of the front axle and the rear axle except the first feedback axle. In this embodiment, when the vehicle battery is in the feedback charging power limited state, if it is determined that the target torque distribution type with the lowest overall feedback efficiency is the front-rear axle common distribution, at this time, the second feedback torque (the sum of the feedback torques of the two motors corresponding to the first feedback axle is the second feedback torque) is distributed to the first feedback axle, and the third feedback torque (the sum of the feedback torques of the two motors corresponding to the second feedback axle is the third feedback torque) is distributed to the second feedback axle, and then, after the energy recovery operation, the feedback power obtained is the smallest (in this embodiment, compared with the front-rear axle mutual resistance distribution and the single axle mutual resistance distribution), so that the feedback power fed back to the vehicle battery for charging is the smallest, and the purpose of protecting the battery and reducing the risk of overcharging is achieved.

[0057] Further, the step S40, that is, the torque distribution operation according to the target torque distribution type and the target demand feedback torque, further includes:

[0058] The first locking mechanism and the second locking mechanism of the vehicle are controlled to be unlocked, and the distributed torque of the axle corresponding to each locking mechanism is evenly distributed to each motor of the axle. The first locking mechanism is used to unlock or lock the power coupling relationship between the left front motor and the right front motor of the front axle; and the second locking mechanism is used to unlock or lock the power coupling relationship between the left rear motor and the right rear motor of the rear axle. Specifically, in the case that the target torque distribution type is front-rear axle common distribution, the first locking mechanism and the second locking mechanism of the vehicle need to be controlled to be unlocked, so that the vehicle speeds of the two motors on the same axle (the first feedback axle or the second feedback axle) are the same. In a further embodiment, the target demand feedback torque can be evenly distributed to the first feedback axle or the second feedback axle of the vehicle, at this time, the wheel end feedback torques of the four driving motors (the left front motor, the right front motor, the left rear motor and the right rear motor) are all distributed as one fourth of the target demand feedback torque.

[0059] In an embodiment, the step S30, that is, the torque distribution operation according to the target torque distribution type and the target demand feedback torque, includes:

[0060] When the target torque distribution type is single-axis mutual resistance distribution, a target locking mechanism is determined, which is the first locking mechanism or the second locking mechanism; the first locking mechanism is used to unlock or lock the power coupling relationship between the left front motor and the right front motor of the front axle; the second locking mechanism is used to unlock or lock the power coupling relationship between the left rear motor and the right rear motor of the rear axle;

[0061] The target locking mechanism is locked, and the fourth feedback torque and the second driving torque are respectively distributed to the two motors connected with the target locking mechanism; the difference between the fourth feedback torque and the second driving torque is equal to the target demand feedback torque. Understandably, the difference between the second feedback torque and the second driving torque (i.e. the target demand feedback torque) cannot be too large, and the target demand feedback torque is less than a preset left-right torque difference, so as to avoid vehicle instability; Understandably, the above-mentioned preset left-right torque difference can be set according to the bearing capacity of the hardware corresponding to the two driving motors on both sides of the target locking mechanism after the reverse torques output by the two driving motors are determined when the target locking mechanism is locked.

[0062] In this embodiment, when the vehicle battery is in a feedback charging power limited state, if the target torque distribution type with the lowest overall feedback efficiency is determined to be single-axis mutual resistance distribution, the target locking mechanism will be locked first, and then the fourth feedback torque and the second driving torque are respectively distributed to the two motors connected with the target locking mechanism.

[0063] In this embodiment, if the target locking mechanism is the second locking mechanism 12, at this time, the two driving motors corresponding to the rear axle jointly distribute the target demand feedback torque, at this time, the second locking mechanism 12 is locked, if the left rear motor outputs the second driving torque, the right rear motor outputs the fourth feedback torque (or the right rear motor outputs the second driving torque, and the left rear motor outputs the fourth feedback torque), at this time, the difference between the fourth feedback torque and the second driving torque will need to be less than the preset left-right torque difference (i.e. within the bearing range of the hardware corresponding to the second locking mechanism), so as to avoid vehicle instability; Understandably, assuming that the target locking mechanism is the first locking mechanism 11, the same applies, which will not be described here.

[0064] It should be understood that the size of the serial number of each step in the above-mentioned embodiment does not mean the order of execution, the execution order of each process should be determined according to its function and inherent logic, and should not constitute any limitation on the implementation process of the embodiment of the present application.

[0065] In an embodiment, as shown in Figure 4 a torque distribution device is provided, which corresponds to the torque distribution method in the above-mentioned embodiment. The torque distribution device comprises:

[0066] The first determining module 11 is configured to determine a target demand feedback torque according to a deceleration signal of the vehicle.

[0067] The second determining module 12 is configured to determine a target torque distribution type with the lowest overall feedback efficiency when the vehicle battery is in a feedback charging power limited state.

[0068] The distribution module 13 is configured to perform a torque distribution operation according to the target torque distribution type and the target demand feedback torque.

[0069] The specific limitations of the torque distribution device can be referred to the limitations of the torque distribution method described above, which will not be repeated here. Each module in the above torque distribution device can be realized by software, hardware and their combinations in whole or in part. Each module described above can be embedded in or independent of the processor in the computer device in hardware form, or can be stored in the memory in the computer device in software form, so as to be called and executed by the processor to perform the operations corresponding to each module.

[0070] The present application also provides a controller for executing the above torque distribution method. The specific limitations of the controller can be referred to the limitations of the torque distribution method described above, which will not be repeated here. Each module in the above controller can be realized by software, hardware and their combinations in whole or in part. Each module described above can be embedded in or independent of the processor in the computer device in hardware form, or can be stored in the memory in the computer device in software form, so as to be called and executed by the processor to perform the operations corresponding to each module. Understandably, the controller can be regarded as one or more computer devices, such as Figure 5 The computer device includes a processor, a memory, a network interface and a database connected by a system bus. The processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program and a database. The internal memory provides an environment for the operating system and the computer program in the non-volatile storage medium to run. The database of the computer device is used to store the data used by the torque distribution method in the above embodiments. The network interface of the computer device is used to communicate with the external terminal through the network connection. The computer program is executed by the processor to implement a torque distribution method.

[0071] The present application also provides a vehicle including the above controller. As shown in Figure 2 The controller includes Figure 2 MCU1, MCU2 and MCU3 shown in Figure 2 The MCU1 is an electronic control of the generator ISG, which is mechanically connected with the engine. The MCU2 is a right front motor (FR_MOT) and a left front motor (FL_MOT) shown inFigure 2 MCU3 is a two-in-one electric control of the right rear motor (RR_MOT) and the left rear motor (RL_MOT) shown in FIG. 1; the three electric controls (MCU1, MCU2 and MCU3) included in the above controllers can be combined or decomposed according to actual application. The first locking mechanism 11 is used to lock or unlock the power coupling relationship of the associated right front motor (FR_MOT) and the left front motor (FL_MOT); the second locking mechanism 12 is used to lock or unlock the power coupling relationship of the associated right rear motor (RR_MOT) and the left rear motor (RL_MOT); and the first locking mechanism 11 and the second locking mechanism 12 are controlled by a low-voltage motor (not shown in the figure). The first locking mechanism 11 and the second locking mechanism 12 can be a differential lock. Figure 2 Figure 2 More specific definitions of the vehicle and the controller can be found in the above definitions of the torque distribution method, which will not be repeated here.

[0072] In an embodiment, a computer readable storage medium is provided, which stores a computer program. The computer program is executed by a processor to implement the above-mentioned torque distribution method.

[0073] In an embodiment, a computer readable storage medium is provided, which stores a computer program. The computer program is executed by a processor to implement the above-mentioned torque distribution method.

[0074] It is understood by those skilled in the art that all or part of the processes in the above-mentioned embodiment methods can be completed by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer readable storage medium, and when executed, can include the processes of the above-mentioned embodiments of each method. Any reference to memory, storage, database or other medium used in the embodiments provided in the present application can include non-volatile and / or volatile memory. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM) or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. As an illustration but not limitation, RAM is available in various forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDR SDRAM), enhanced SDRAM (ESDRAM), synchronous link (Synchlink) DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM), etc.

[0075] ​Those skilled in the art can clearly understand that, for the convenience and brevity of description, only the above-mentioned division of each functional unit and module is exemplified, and in actual application, the above-mentioned functions can be completed by different functional units and modules according to needs, that is, the internal structure of the device is divided into different functional units or modules to complete all or part of the functions described above.

[0076] The above-described embodiments are only used to illustrate the technical solutions of the present application, rather than limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that the technical solutions recorded in the foregoing embodiments can still be modified, or some technical features can be replaced by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application, and should be included in the protection scope of the present application.

Claims

1. A torque distribution method, characterized in that, include: The target required feedback torque is determined based on the vehicle's deceleration signal; When the vehicle battery is in a state of limited regenerative charging power, determine the target torque distribution type with the lowest overall regenerative efficiency; The determination of the target torque distribution type with the lowest overall feedback efficiency includes: determining the target torque distribution type with the lowest overall feedback efficiency from preset distribution types based on the current vehicle speed; wherein, when the current vehicle speed is less than or equal to a preset vehicle speed, the preset distribution types include at least two of the following: front and rear axle joint distribution, front and rear axle mutual offset distribution, and single axle mutual offset distribution; when the current vehicle speed is greater than a preset vehicle speed, the preset distribution types include front and rear axle joint distribution and front and rear axle mutual offset distribution; the front and rear axle mutual offset distribution refers to allocating a first feedback torque to one of the front and rear axles of the vehicle, and allocating a first drive torque to the other axle; the difference between the first feedback torque and the first drive torque is equal to the target required feedback torque; the single axle mutual offset distribution refers to allocating a fourth feedback torque and a second drive torque to the two motors connected to the target locking mechanism respectively; the difference between the fourth feedback torque and the second drive torque is equal to the target required feedback torque; the two motors connected to the target locking mechanism refer to the left front motor and right front motor connected to the first locking mechanism, or the left rear motor and right rear motor connected to the second locking mechanism; The torque distribution operation is performed based on the target torque distribution type and the target demand feedback torque.

2. The torque distribution method as described in claim 1, characterized in that, The limited feedback charging power states include: The maximum permissible charging power of the vehicle battery is less than or equal to a preset power value; or... The current SOC value of the vehicle battery exceeds a preset SOC threshold.

3. The torque distribution method as described in claim 1, characterized in that, The step of performing torque allocation operation based on the target torque allocation type and the target demand feedback torque includes: When the target torque distribution type is front and rear axle offset distribution, a first feedback torque is allocated to the target feedback axle, and a first drive torque is allocated to the target drive axle; the difference between the first feedback torque and the first drive torque is equal to the target required feedback torque; the target feedback axle is the front axle or the rear axle of the vehicle; the target drive axle is the other axle between the front axle and the rear axle besides the target feedback axle.

4. The torque distribution method as described in claim 1, characterized in that, The step of performing torque allocation operation based on the target torque allocation type and the target demand feedback torque includes: When the target torque distribution type is a joint distribution between the front and rear axles, a second feedback torque is allocated to the first feedback axle, and a third feedback torque is allocated to the second feedback axle; the sum of the second feedback torque and the third feedback torque is equal to the target required feedback torque; the first feedback axle is the front axle or the rear axle of the vehicle; the second feedback axle is the other axle between the front axle and the rear axle besides the first feedback axle.

5. The torque distribution method as described in claim 3 or 4, characterized in that, The step of performing torque allocation operation based on the target torque allocation type and the target demand feedback torque further includes: The first and second locking mechanisms of the vehicle are controlled to unlock, and the distribution torque corresponding to each axle of each locking mechanism is evenly distributed to each motor of that axle. The first locking mechanism is used to unlock or lock the power coupling relationship between the left front motor and the right front motor of the front axle; the second locking mechanism is used to unlock or lock the power coupling relationship between the left rear motor and the right rear motor of the rear axle.

6. The torque distribution method as described in claim 1, characterized in that, The step of performing torque allocation operation based on the target torque allocation type and the target demand feedback torque includes: When the target torque distribution type is single-axis mutual abutment distribution, a target locking mechanism is determined, which is either a first locking mechanism or a second locking mechanism; the first locking mechanism is used to unlock or lock the power coupling relationship between the left front motor and the right front motor of the front axle; the second locking mechanism is used to unlock or lock the power coupling relationship between the left rear motor and the right rear motor of the rear axle; The target locking mechanism is controlled to lock, and a fourth feedback torque and a second drive torque are respectively distributed to the two motors connected to the target locking mechanism; the difference between the fourth feedback torque and the second drive torque is equal to the target required feedback torque.

7. The torque distribution method as described in claim 1, characterized in that, The step of determining the target torque distribution type with the lowest overall feedback efficiency from the preset distribution types based on the current vehicle speed includes: Based on the preset calibration efficiency parameters, determine the predicted feedback efficiency value corresponding to each preset allocation type at the current vehicle speed; The preset allocation type corresponding to the minimum predicted feedback efficiency value is determined as the target torque allocation type.

8. A torque distribution device, characterized in that, include: The first determining module is used to determine the target required feedback torque based on the vehicle's deceleration signal; The second determining module is used to determine the target torque distribution type with the lowest overall feedback efficiency when the vehicle battery is in a state of limited feedback charging power. The determination of the target torque distribution type with the lowest overall feedback efficiency includes: determining the target torque distribution type with the lowest overall feedback efficiency from preset distribution types based on the current vehicle speed; wherein, when the current vehicle speed is less than or equal to a preset vehicle speed, the preset distribution types include at least two of the following: front and rear axle joint distribution, front and rear axle mutual offset distribution, and single axle mutual offset distribution; when the current vehicle speed is greater than a preset vehicle speed, the preset distribution types include front and rear axle joint distribution and front and rear axle mutual offset distribution; the front and rear axle mutual offset distribution refers to allocating a first feedback torque to one of the front and rear axles of the vehicle, and allocating a first drive torque to the other axle; the difference between the first feedback torque and the first drive torque is equal to the target required feedback torque; the single axle mutual offset distribution refers to allocating a fourth feedback torque and a second drive torque to the two motors connected to the target locking mechanism respectively; the difference between the fourth feedback torque and the second drive torque is equal to the target required feedback torque; the two motors connected to the target locking mechanism refer to the left front motor and right front motor connected to the first locking mechanism, or the left rear motor and right rear motor connected to the second locking mechanism; The allocation module is used to perform torque allocation operations based on the target torque allocation type and the target demand feedback torque.

9. A controller, characterized in that, The controller is used to execute the torque distribution method as described in any one of claims 1 to 8.

10. A vehicle, characterized in that, Includes the controller as described in claim 9.

11. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by the processor, it implements the torque distribution method as described in any one of claims 1 to 8.

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