CN118182165A - Power and chassis fusion torque architecture based on electric four-wheel drive, distribution method and medium - Google Patents

Abstract

The invention discloses a torque framework, a distribution method and a medium based on electric four-wheel drive power and chassis fusion, which calculate driving demand torque according to manual driving, automatic driving and vehicle longitudinal auxiliary driving arbitration; calculating a front axle demand torque and a rear axle demand torque according to the driving demand torque; calculating the required torque of each wheel according to the front axle required torque and the rear axle required torque; the final motor demand torque is calculated from the demand torque required for each wheel. The invention fuses the power control of the power system and the chassis system, and constructs a fused torque control framework. The torque architecture can be flexibly configured and deployed, the interface is simple, the torque control flow is concise and clear, the interaction complexity of the system is reduced, the response of the system is improved, and the safety control of the vehicle is improved.

Description

Power and chassis fusion torque architecture based on electric four-wheel drive, distribution method and medium

Technical Field

The invention belongs to the technical field of vehicle torque distribution, and particularly relates to a torque architecture, a distribution method and a medium based on electric four-wheel drive power and chassis fusion.

Background

The development of new energy automobiles, pure electric automobiles and hybrid electric automobiles are becoming more and more popular in the market, the automobiles are provided with partial or all energy sources by power batteries and power driven actuators by adopting motors, and more automobiles adopt a distributed driving mode, namely a plurality of motors are arranged on the front axle and the rear axle of the automobile, so that the automobile has strong enough power and can provide strong enough electric braking capability; meanwhile, with the great revolution of the intelligent network-connected automobile industry, the automobile electronic architecture gradually develops from a distributed type to a central centralized electronic architecture, and the integration of power and chassis systems gradually becomes a development trend.

In the prior art, the power system and the chassis system are controlled by handshake interaction through interfaces, an interaction handshake mechanism needs to be defined, and an interaction interface is matched, so that the problems that functions and software overlap, the interaction between the power system and the chassis system is complex, the interaction conflict exists, the calibration and the matching between the functions are difficult, the control response is slow and the like are solved.

Disclosure of Invention

In order to solve the problems of complex interaction, interaction conflict, difficult calibration and matching between functions, slow control response and the like caused by the fact that a power system and a chassis system control power simultaneously in the prior art, the invention provides a torque framework, a distribution method and a medium based on electric four-wheel drive power and chassis fusion.

The invention discloses a torque framework based on electric four-wheel drive power and chassis fusion, which comprises the following components: a driving demand torque calculation module, a shaft demand torque calculation module, a wheel demand torque calculation module, and a motor demand torque calculation module;

The driving demand torque calculation module is used for calculating driving demand torque according to manual driving, automatic driving and vehicle longitudinal auxiliary driving arbitration;

the axle demand torque calculation module is used for calculating front axle demand torque and rear axle demand torque according to driving demand torque;

The wheel required torque calculation module is used for calculating the wheel required torque of each wheel according to the front axle required torque and the rear axle required torque;

The motor demand torque calculation module is configured to calculate a final motor demand torque according to the wheel demand torque of each wheel.

Further, the calculated driving demand torque module is further configured to:

Determining a driving torque distribution coefficient K1 and a driving torque arbitration coefficient K2 according to manual driving, automatic driving and vehicle longitudinal auxiliary driving arbitration;

and carrying out weighted calculation on the initial driving torque and the arbitrated driving torque according to the driving torque distribution coefficient K1 and the driving torque arbitration coefficient K2 to obtain driving demand torque.

Further, the method for determining the driving torque distribution coefficient K1 and the driving torque arbitration coefficient K2 includes:

when the manual driving is started and the auxiliary driving function is not started, K1 is a first set value, and K2 is a second set value;

when manual driving is started and auxiliary driving works, K1 is a value which changes according to the vehicle speed, and K2 is a second set value;

When the automatic driving or constant speed cruising function is operated or the longitudinal stable torque control is enabled, K1 is a second set value, and K2 is a first set value.

Further, the method for determining the arbitrated driving torque includes:

When the vehicle is in manual driving, the arbitrated driving torque is equal to the driving torque in the manual driving mode;

When the vehicle is in automatic driving, then arbitrating driving torque to be equal to driving torque in automatic driving mode;

When the vehicle starts the auxiliary driving, the arbitrated driving torque is equal to the driving torque which is the smaller value of the manual driving torque and the auxiliary driving torque.

Further, the method for determining the value of K1 according to the change of the vehicle speed comprises the following steps: obtaining a difference value between the highest vehicle speed and the actual vehicle speed; k1 decreases with decreasing difference, preferably K1 ε [0,1].

Further, the axle demand torque calculation module is further configured to:

Determining a front axle torque arbitration coefficient K4 according to the enabling state of the front axle longitudinal stability function;

Weighting calculation is carried out on driving demand torque and front axle arbitration torque according to a set axle torque distribution coefficient K3 and a front axle torque arbitration coefficient K4 to obtain front axle demand torque;

The shaft torque distribution coefficient K3 is set according to the efficiency of the power system, the speed of the vehicle, the opening degree of an accelerator pedal and the gradient of a ramp;

the front axle torque arbitration coefficient K4 is used to indicate whether the front axle longitudinal stability function is on.

Further, the axle demand torque calculation module is further configured to:

determining a rear axle torque arbitration coefficient K5 according to the enabling state of the rear axle longitudinal stability function;

weighting calculation is carried out on driving demand torque and rear axle arbitration torque according to a set axle torque distribution coefficient K3 and a rear axle torque arbitration coefficient K5 to obtain rear axle demand torque;

the rear axle torque arbitration coefficient K5 is used to indicate whether the rear axle longitudinal stability function is on.

The front axle arbitration torque and the rear axle arbitration torque are obtained by arbitration and fusion calculation according to economic distribution and dynamic distribution and longitudinal torque control of the vehicle. The economical distribution comprises a motor efficiency optimal distribution principle and a battery efficiency optimal distribution principle, and the dynamic distribution principle is used for calculating according to the vehicle speed, the accelerator pedal opening and the gradient of the ramp, and distributing the torque of the front axle and the rear axle.

Further, the wheel demand torque calculation module is further configured to:

Obtaining a front left wheel torque distribution coefficient K6 and a rear left wheel torque distribution coefficient K7 according to the vehicle slip state and the vehicle turning capacity;

Obtaining a front left wheel torque arbitration coefficient K8 and a front right wheel torque arbitration coefficient K9 according to the enabling state of the tire lateral stability function;

the front axle required torque and the front left wheel arbitration torque are weighted according to the front left wheel torque distribution coefficient K6 and the front left wheel torque arbitration coefficient K8 to obtain the front left wheel required torque;

and carrying out weighted calculation on the front axle required torque and the front right wheel arbitration torque according to the front left wheel torque distribution coefficient K6 and the front right wheel torque arbitration coefficient K9 to obtain the front right wheel required torque.

Further, the wheel demand torque calculation module is further configured to:

Obtaining a front left wheel torque distribution coefficient K6 and a rear left wheel torque distribution coefficient K7 according to the vehicle slip state and the vehicle turning capacity;

Obtaining a rear left wheel torque arbitration coefficient K10 and a rear right wheel torque arbitration coefficient K11 according to the enabling state of the tire lateral stability function;

Weighting calculation is carried out on the rear axle required torque and the rear left wheel arbitration torque according to the rear left wheel torque distribution coefficient K7 and the rear left wheel torque arbitration coefficient K10 to obtain the rear left wheel required torque;

And carrying out weighted calculation on the rear axle required torque and the rear right wheel arbitration torque according to the rear left wheel torque distribution coefficient K7 and the rear right wheel torque arbitration coefficient K11 to obtain the rear right wheel required torque.

The front left wheel arbitration torque, the front right wheel arbitration torque, the rear left wheel arbitration torque and the rear right wheel arbitration torque are torque obtained by arbitration according to the slip state of the vehicle and whether the vehicle runs on a curve path.

Further, front left and rear left wheel torque distribution coefficients K6 and K7 are obtained according to the slip rate; when the slip rate is in the set range, the values of K6 and K7 are both the third set value; when the setting range is out, K6 and K7 are smaller than a third setting value; and the larger the deviation from the set range is, the smaller the value is.

Further, front left and rear left wheel torque distribution coefficients K6 and K7 are obtained according to the target yaw rate and the actual yaw rate difference; the smaller the yaw difference, the closer the distribution coefficients K6 and K7 approach 1; as the yaw difference increases, the distribution coefficients K6 and K7 decrease.

The technical effects of obtaining the front left wheel torque distribution coefficient K6 and the rear left wheel torque distribution coefficient K7 according to the vehicle slip state and the vehicle turning capacity include: when the vehicle is in a slipping state, distributing the wheel torque to the left and right vehicle end motor torques so as to prevent the vehicle from slipping; if the vehicle is traveling in a curve, the wheel torque is distributed to the left and right vehicle end motor torques to prevent oversteer or understeer of the vehicle.

Further, the motor demand torque calculation module is further configured to:

obtaining a motor torque arbitration coefficient K12 according to the enabling state of the anti-shake function of the motor;

and carrying out weighted calculation on the wheel demand torque and the arbitration motor torque according to the motor torque arbitration coefficient K12 to obtain the motor demand torque. The wheel demand torque is the calculated final motor demand torque for the corresponding wheel.

The second purpose of the invention is achieved by a torque distribution method for integrating power and chassis of an electric four-wheel drive, which comprises the following steps:

Calculating driving demand torque according to manual driving, automatic driving and vehicle longitudinal auxiliary driving arbitration;

Calculating a front axle required torque and a rear axle required torque according to the driving required torque;

Calculating a wheel demand torque for each wheel from the front axle demand torque and the rear axle demand torque;

And calculating the final motor required torque according to the wheel required torque of each wheel.

A non-transitory computer readable storage medium, having stored thereon a computer program which when executed by a processor, performs the steps of the power and chassis fusion torque distribution method of the electric four-wheel drive.

The beneficial effects of the invention include:

The invention fuses the power control of the power system and the chassis system, and constructs a fused torque control framework. The torque architecture can be flexibly configured and deployed, the interface is simple, the torque control flow is concise and clear, the interaction complexity of the system is reduced, the response of the system is improved, and the safety control of the vehicle is improved.

Drawings

FIG. 1 is a schematic diagram of a system according to the present invention;

fig. 2 is a schematic diagram of a second embodiment of the system according to the present invention.

Detailed Description

The following detailed description is presented to explain the claimed invention and to enable those skilled in the art to understand the claimed invention. The scope of the invention is not limited to the following specific embodiments. It is also within the scope of the invention to include the claims of the present invention as made by those skilled in the art, rather than the following detailed description.

The embodiment of the invention provides a power and chassis fusion torque framework based on electric four-wheel drive, which comprises the following components:

The driving demand torque calculation module is used for calculating driving demand torque according to manual driving, automatic driving and vehicle longitudinal auxiliary driving arbitration;

The axle demand torque calculation module is used for calculating front axle demand torque and rear axle demand torque according to the driving demand torque;

The wheel demand torque calculation module is used for calculating the wheel demand torque of each wheel according to the front axle demand torque and the rear axle demand torque;

and the motor required torque calculation module is used for calculating the final motor required torque according to the wheel required torque of each wheel.

In the above technical solution, the driving demand torque calculation module is further configured to:

determining a driving torque distribution coefficient K1 and a driving torque arbitration coefficient K2 according to manual driving, automatic driving and vehicle longitudinal auxiliary driving arbitration;

and carrying out weighted calculation on the initial driving torque and the arbitrated driving torque according to the driving torque distribution coefficient K1 and the driving torque arbitration coefficient K2 to obtain driving demand torque.

In the above technical solution, the method for determining the driving torque distribution coefficient K1 and the driving torque arbitration coefficient K2 includes:

when the manual driving is started and the auxiliary driving function is not started, K1 is a first set value, and K2 is a second set value;

when manual driving is started and auxiliary driving works, K1 is a value which changes according to the vehicle speed, and K2 is a second set value;

When the automatic driving or constant speed cruising function is operated or the longitudinal stable torque control is enabled, K1 is a second set value, and K2 is a first set value.

In the above technical solution, the axle demand torque calculation module is further configured to:

Determining a front axle torque arbitration coefficient K4 according to the enabling state of the front axle longitudinal stability function;

Weighting calculation is carried out on driving demand torque and front axle arbitration torque according to a set axle torque distribution coefficient K3 and a front axle torque arbitration coefficient K4 to obtain front axle demand torque;

the front axle torque arbitration coefficient K4 is used to indicate whether the front axle longitudinal stability function is on.

In the above technical solution, the axle demand torque calculation module is further configured to:

determining a rear axle torque arbitration coefficient K5 according to the enabling state of the rear axle longitudinal stability function;

weighting calculation is carried out on driving demand torque and rear axle arbitration torque according to a set axle torque distribution coefficient K3 and a rear axle torque arbitration coefficient K5 to obtain rear axle demand torque;

the rear axle torque arbitration coefficient K5 is used to indicate whether the rear axle longitudinal stability function is on.

In the above technical solution, the wheel demand torque calculation module is further configured to:

Obtaining a front left wheel torque distribution coefficient K6 and a rear left wheel torque distribution coefficient K7 according to the vehicle slip state and the vehicle turning capacity;

Obtaining a front left wheel torque arbitration coefficient K8 and a front right wheel torque arbitration coefficient K9 according to the enabling state of the tire lateral stability function;

the front axle required torque and the front left wheel arbitration torque are weighted according to the front left wheel torque distribution coefficient K6 and the front left wheel torque arbitration coefficient K8 to obtain the front left wheel required torque;

and carrying out weighted calculation on the front axle required torque and the front right wheel arbitration torque according to the front left wheel torque distribution coefficient K6 and the front right wheel torque arbitration coefficient K9 to obtain the front right wheel required torque.

In the above technical solution, the wheel demand torque calculation module is further configured to:

Obtaining a front left wheel torque distribution coefficient K6 and a rear left wheel torque distribution coefficient K7 according to the vehicle slip state and the vehicle turning capacity;

Obtaining a rear left wheel torque arbitration coefficient K10 and a rear right wheel torque arbitration coefficient K11 according to the enabling state of the tire lateral stability function;

Weighting calculation is carried out on the rear axle required torque and the rear left wheel arbitration torque according to the rear left wheel torque distribution coefficient K7 and the rear left wheel torque arbitration coefficient K10 to obtain the rear left wheel required torque;

And carrying out weighted calculation on the rear axle required torque and the rear right wheel arbitration torque according to the rear left wheel torque distribution coefficient K7 and the rear right wheel torque arbitration coefficient K11 to obtain the rear right wheel required torque.

The front left wheel arbitration torque, the front right wheel arbitration torque, the rear left wheel arbitration torque and the rear right wheel arbitration torque are torque obtained by arbitration according to the slip state of the vehicle and whether the vehicle runs on a curve path.

In the above technical solution, the motor required torque calculation module is further configured to:

obtaining a motor torque arbitration coefficient K12 according to the enabling state of the anti-shake function of the motor; k12=1 when the motor anti-shake function is not operating, otherwise k12=0.

And carrying out weighted calculation on the wheel demand torque and the arbitration motor torque according to the motor torque arbitration coefficient K12 to obtain the motor demand torque.

The torque architecture has the beneficial effects that: according to the flow direction of driving torque, four main torque service modules are defined from a driver end, a shaft end and a wheel end to a motor end: total torque calculation, axle torque calculation, wheel torque calculation, motor torque calculation. The vehicle longitudinal and transverse movement unified torque control function is flexibly and smoothly realized, and the functions of the platform vehicle type can be freely combined and called according to the vehicle type configuration, so that the platform vehicle type function is more conveniently and rapidly realized.

In the torque architecture, according to the four-driving force system, the torque driving functions of the power system and the chassis system are combined, performances such as vehicle economy, power performance, stability and curve driving performance are considered, torque is taken as an axis, and torque calculation is divided into four sub-modules: the driving demand torque calculation module, the axle demand torque calculation module, the wheel demand torque calculation module and the motor demand torque calculation module realize torque control of related area functions, finally converge into torque output of a control motor, and realize power control of a vehicle.

In the above torque architecture, for the driving demand torque calculation module, the driving demand torque obtained includes a driving demand torque for manual driving or automatic driving, and if the auxiliary driving is on, the driving demand torque for auxiliary driving is obtained.

The driving torque comprises manual driving, automatic driving, an auxiliary function and a longitudinal stable control function, manual driving is usually used as a main driving torque demand, and a manual driving torque request module calculates driving demand torque according to driving information such as an accelerator pedal, a brake pedal, a gear, a steering wheel and the like;

When the automatic driving is performed, the torque calculated by the automatic driving system is used as the driving demand torque; if the constant speed cruising function is provided, calculating a required torque or a control proportion according to a target speed and an actual speed of the constant speed cruising; the maximum vehicle speed control module calculates the required torque or control proportion according to the set maximum vehicle speed; the vehicle longitudinal torque calculation module calculates a total longitudinal demand torque based on the vehicle stability demand.

In the torque architecture, based on the manual driving mode, the automatic driving mode and the auxiliary driving mode, the driving torque in the corresponding driving mode is calculated, and the total driving demand torque is calculated through arbitration and fusion of the driving torques.

In the above torque architecture, the driving demand torque calculation module includes: the system comprises a manual driving torque calculation sub-module, an automatic driving torque calculation sub-module, a constant-speed cruising torque calculation sub-module, a torque limit value calculation sub-module, a vehicle longitudinal torque request sub-module, a driving torque arbitration sub-module, a driving total torque calculation sub-module and a vehicle transverse torque request sub-module, wherein the sub-functional modules can be expanded according to scenes and requirements.

The manual driving torque calculation sub-module is used for calculating manual driving torque according to the accelerator pedal, the brake pedal, the gear and the vehicle speed information.

The automatic driving torque calculation sub-module is used for calculating automatic driving torque according to the sensing information acquired by the system during automatic driving.

The constant-speed cruising torque calculation submodule is used for calculating constant-speed cruising driving torque according to the set cruising speed and the current speed.

The torque limit value calculation submodule is used for calculating a driving torque limit value according to the set maximum vehicle speed and the set current vehicle speed; so that the control vehicle speed of the total torque output does not exceed the maximum vehicle speed.

The vehicle longitudinal torque request submodule is used for requesting total torque of increase and decrease of longitudinal torque of the vehicle when a vehicle stability function (such as ESC request) is enabled, and is also used for providing vehicle longitudinal torque control service for the axle demand torque calculation module;

The driving torque arbitration submodule is used for arbitrating and fusing functions when the manual driving mode, the automatic driving mode, the constant speed cruising mode, the highest vehicle speed control and the vehicle longitudinal control function are enabled, and calculating an arbitration driving torque, a driving torque distribution coefficient K1 and a driving torque arbitration coefficient K2.

The driving total torque calculation submodule is used for calculating total driving demand torque according to the arbitrated driving torque, the driving torque arbitration coefficient and the driving torque distribution coefficient;

The vehicle lateral torque request sub-module refers to a total torque request for the lateral direction of the vehicle when the vehicle auxiliary functions (such as in-situ turn around) are enabled.

Specifically, the calculation method of the driving demand torque T _{Drv_Out} includes:

T_{Drv_Out}＝T_{Drv_In}×K1+T_{Arb_Drv}×K2

Wherein:

t _{Drv_In} is the initial driving torque;

t _{Arb_Drv} is arbitrating driving torque;

t _{Drv_Out} is the driving demand torque calculated after arbitration;

k1 is a driving torque distribution coefficient;

k2 is the driving torque arbitration coefficient;

k1=1, k2=0 when the person is driving and the auxiliary driving function is not operating;

When the person drives and auxiliary functions such as the highest vehicle speed and the like work, K1 is a value which changes according to the vehicle speed, K1 is reduced along with the reduction of the difference value between the highest vehicle speed and the actual vehicle speed, K1 epsilon [0,1], and K2=0;

K1=0, k2=1 when the autopilot or cruise control function is active or the longitudinal steady torque control.

In the torque architecture, the axle demand torque calculation module comprises a front axle torque calculation sub-module and a rear axle torque calculation sub-module; after the arbitrated driving demand torque T _{Drv_Out} is calculated, the driving demand torque is output to the axle demand torque calculation module after the torque filtering smoothing treatment. When the axle demand torque is calculated, the front and rear axle torques are distributed according to the characteristics of the four-driving-force system in consideration of the economical efficiency and the dynamic property of the power vehicle so as to meet the economical efficiency and/or dynamic property target requirements. The economic distribution mainly considers the efficiency of the power system, and distributes according to the optimal principle of the front and rear axle power system efficiency in the current vehicle state; the dynamic property is mainly that the dynamic response (such as acceleration and deceleration of the vehicle) and the load change of the front axle and the rear axle are detected when the vehicle runs, and the front axle and the rear axle are distributed when the vehicle runs on a slope. For economic distribution and dynamic distribution, the two components may not be simultaneously compatible, and arbitration and fusion are needed to meet the dynamic or economic targets, or a proper balance point is found between the dynamic and the economic, so that front axle arbitration torque and rear axle arbitration torque after arbitration are obtained.

In another embodiment, the axle demand torque calculation module includes: the system comprises a torque filtering sub-module, an economical allocation sub-module, a dynamic allocation sub-module, a vehicle longitudinal torque control sub-module, a shaft torque arbitration and allocation sub-module and a shaft torque calculation sub-module.

The torque filtering submodule is used for carrying out smooth filtering treatment on the arbitrated driving demand torque T _{Drv_Out} so as to enable the driving torque to be smooth and improve the control comfort of the vehicle;

The economic distribution submodule is used for distributing front and rear axle torque according to the efficiency of the power system;

The dynamic distribution submodule is used for calculating according to the vehicle speed, the opening of an accelerator pedal and the gradient of a ramp, and distributing the torque of the front shaft and the rear shaft;

the vehicle longitudinal torque control submodule is used for controlling and requesting front and rear axle torque when a vehicle stability function is enabled;

The shaft torque arbitration and distribution is to perform arbitration and fusion according to economic distribution, dynamic distribution and longitudinal torque control of the vehicle, and front and rear shaft arbitration torques T _{Arb_Axle_F} and T _{Arb_Axle_R}, front and rear shaft torque arbitration coefficients K4 and K5 and a shaft torque distribution coefficient K3 are calculated;

the axle torque calculation sub-module is used for calculating the torque requests of the front axle and the rear axle according to the front axle arbitration torque, the rear axle arbitration torque, the front axle torque arbitration coefficient, the rear axle torque arbitration coefficient and the axle torque distribution coefficient.

Specifically, the method for calculating the required torque of the front and rear axles includes:

T_{Axle_F}＝T_{Drv_Out}×K3×K4+T_{Arb_Axle_F}×(1-K4)

T_{Axle_R}＝T_{Drv_Out}×(1-K3)×K5+T_{Arb_Axle_R}×(1-K5)

Wherein:

T _{Axle_F} is the front axle demand torque;

t _{Axle_R} is the rear axle demand torque;

T _{Arb_Axle_F} is front axle arbitration torque (i.e., front axle torque after arbitration);

T _{Arb_Axle_R} is rear axle arbitration torque (i.e., rear axle torque after arbitration);

K3 is a shaft torque distribution coefficient; k3 ε [0,1], the preferred value is 0.5;

k4 and K5 are front and rear axle torque arbitration coefficients respectively;

K4=1 when the front axle longitudinal stability function is not working, otherwise k4=0;

K5=1 when the rear axle longitudinal stability function is not working, otherwise k5=0.

For the wheel demand torque calculation module, different power system configurations correspond to different wheel torque calculation methods, and for the torque of the double motors (one-shaft single motor and the other-shaft single motor) after shaft division is directly distributed to the front motor and the rear motor, the left and right torque distribution of the coaxial motors is not needed; for a configuration with two motors on the same shaft, the shaft torque needs to be distributed to the left and right motors. On the basis of considering the configuration of a power system, the turning characteristic and the running stability of the vehicle are also required, the left motor torque and the right motor torque are distributed on the axle torque so as to meet the running steering characteristic and the running stability of the vehicle at a curve, the arbitration and the fusion between the curve distribution and the driving anti-skid distribution are required, and the required torque of a motor end is calculated.

In the above torque architecture, the wheel demand torque calculation module includes: the system comprises an anti-skid allocation sub-module, a curve allocation sub-module, a vehicle transverse torque request sub-module, a wheel torque arbitration and allocation sub-module and a wheel torque calculation sub-module.

The anti-skid distribution sub-module is used for distributing wheel torque for improving the stability of the vehicle when the vehicle skids;

the curve allocation submodule is used for allocating wheel torque for improving the turning capacity of the vehicle when the vehicle runs in a curve;

when the vehicle transverse torque control submodule is used for enabling a vehicle auxiliary function (such as in-situ turning), a torque command is sent to a motor controller through a system to control a motor;

the wheel torque arbitration and distribution submodule is used for performing arbitration and fusion according to the anti-skid distribution submodule, the curve distribution submodule and the vehicle transverse control submodule, and calculating wheel arbitration torque, a wheel torque arbitration coefficient and a wheel torque distribution coefficient;

The wheel torque calculation sub-module is used for calculating the wheel demand torque of each wheel according to the wheel arbitration torque, the wheel arbitration coefficient and the left and right wheel torque distribution coefficients.

Specifically, the method for calculating the wheel torque includes:

T_{Wheel_FL}＝T_{Axle_F}×K6×K8+T_{Arb_Wheel_FL}×(1-K8)

T_{Wheel_FR}＝T_{Axle_F}×(1-K6)×K9+T_{Arb_Wheel_FR}×(1-K9)

T_{Wheel_RL}＝T_{Axle_R}×K7×K10+T_{Arb_Wheel_RL}×(1-K10)

T_{Wheel_RR}＝T_{Axle_R}×(1-K7)×K11+T_{Arb_Wheel_RR}×(1-K11)

Wherein:

T _{Axle_F} is the front axle demand torque;

t _{Axle_R} is the rear axle demand torque;

T _{Arb_Wheel_FL} is front left wheel arbitration torque;

T _{Arb_Wheel_FR} is the front right wheel arbitration torque;

T _{Arb_Wheel_RL} is the rear left wheel arbitration torque;

T _{Arb_Wheel_RR} is the rear right wheel arbitration torque;

T _{Wheel_FL} is the front left wheel required torque;

T _{Wheel_FR} is the front right wheel demand torque;

t _{Wheel_RL} is the torque required by the rear left wheel;

T _{Wheel_RR} is the torque required by the rear right wheel;

k6 and K7 are respectively the front left wheel and the rear left wheel torque distribution coefficients;

k8, K9, K10 and K11 are front left, front right, rear left and rear right wheel torque arbitration coefficients respectively;

K8=1 when the front left wheel lateral stability function is not working, otherwise k8=0;

k9=1 when the current right wheel lateral stability function is not working, otherwise k9=0;

K10=1 when the rear left wheel lateral stability function is not working, otherwise k10=0;

K11=1 when the rear right wheel lateral stability function is not active, otherwise k11=0.

When the vehicle is in a slipping state, the motor torques at the left and right vehicle ends are distributed to obtain a front left wheel arbitration torque T _{Arb_Wheel_FL}, a front right wheel arbitration torque T _{Arb_Wheel_FR}, a rear left wheel arbitration torque T _{Arb_Wheel_RL} and a rear right wheel arbitration torque T _{Arb_Wheel_RR} so as to prevent the vehicle from slipping; obtaining front left and rear left wheel torque distribution coefficients K6 and K7 according to the slip rate; in the embodiment, when the slip rate is 10% -30%, the values of K6 and K7 are 1; when the value is outside the range, K6 and K7 are smaller than 1, and the larger the deviation from the range is, the smaller the value is;

If the vehicle is running on a curve, the wheel torque is distributed to the motor torque at the left and right vehicle ends to obtain a front left wheel arbitration torque T _{Arb_Wheel_FL}, a front right wheel arbitration torque T _{Arb_Wheel_FR}, a rear left wheel arbitration torque T _{Arb_Wheel_RL} and a rear right wheel arbitration torque T _{Arb_Wheel_RR} so as to prevent the vehicle from oversteering or understeering; obtaining front left and rear left wheel torque distribution coefficients K6 and K7 according to the target yaw rate and the actual yaw rate difference; the larger the yaw difference is, the smaller the distribution coefficient is, and the smaller the yaw difference is, the closer the distribution coefficient is to 1.

For the motor required torque calculation module, after driving required torque is distributed to motor end torque in consideration of vehicle economy, dynamic property, stability, curve running performance and the like, motor inherent characteristics including motor process shake control processing, but not limited to motor characteristics are considered, motor torque is arbitrated and fused, and final motor required torque is calculated and output to a motor.

In the above torque architecture, the motor demand torque calculation module includes: the motor anti-shake control sub-module, the motor torque arbitration sub-module and the motor torque calculation sub-module.

The motor anti-shake control submodule is used for sending a control request and a function activation instruction to the control system when the motor controller system judges that shake control is needed during motor operation, and the control system controls the motor according to motor requirements after receiving the instruction;

the motor torque arbitration sub-module is used for arbitrating according to motor anti-shake control parameters (including vehicle speed, wheel speed and motor rotating speed) and the current vehicle state (shake or non-shake), and calculating arbitration motor torque T _{Arb_Motor} and motor torque arbitration coefficient K12.

The motor torque calculation calculates a motor torque based on the wheel demand torque, the arbitration motor torque, and the motor torque arbitration coefficient.

The motor torque control submodule calculates final motor demand torque according to motor capacity.

Specifically, the calculation method of the required torque of each motor includes:

T_Motor＝T_Wheel×K12+T_{Arb_Motor}×(1-K12)

Wherein:

T _Motor is the motor demand torque;

T _Wheel is the wheel required torque corresponding to each motor; if the motor torque corresponding to the front left wheel is calculated, T _Wheel＝T_{Wheel_FL};

t _{Arb_Motor} is the arbitrated motor torque;

When the motor anti-shake function is not started, k12=1, and the arbitration motor torque T _Motor value is not required to be calculated;

When the motor anti-shake function is started and the vehicle is in a shake state, the arbitration motor torque T _Motor is the original motor torque calculated by the vehicle according to the motor anti-shake control parameters (including the speed, the wheel speed and the motor rotating speed);

k12 is a motor torque arbitration coefficient, k12=1 when the motor anti-shake function is not on or when the motor anti-shake function is on and the vehicle is not shaking, otherwise k12=0.

The embodiment of the invention also provides a power and chassis fusion torque distribution method based on electric four-wheel drive, which comprises the following steps:

calculating a driving demand torque according to the driving mode and the longitudinal stable torque control enabling state;

calculating a front axle demand torque and a rear axle demand torque according to the driving demand torque;

Calculating a wheel demand torque for each wheel from the front axle demand torque and the rear axle demand torque;

And calculating the final motor required torque according to the wheel required torque of each wheel.

The embodiment of the present invention further provides a computer readable storage medium, where a computer program is stored, where the computer program includes program instructions, and when the program instructions are executed by a processor, the program instructions implement each step of the method of the present invention, which is not described herein.

The computer readable storage medium may be the data transmission apparatus provided in any of the foregoing embodiments or an internal storage unit of a computer device, for example, a hard disk or a memory of the computer device. The computer readable storage medium may also be an external storage device of the computer device, such as a plug-in hard disk, a smart memory card (SMART MEDIA CARD, SMC), a Secure Digital (SD) card, a flash memory card (FLASH CARD), etc. that are provided on the computer device.

Further, the computer-readable storage medium may also include both internal storage units and external storage devices of the computer device. The computer-readable storage medium is used to store the computer program and other programs and data required by the computer device. The computer-readable storage medium may also be used to temporarily store data to be output or already output.

It will be appreciated by those skilled in the art that embodiments of the present invention may be provided as a method, system, or computer program product. Accordingly, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present invention may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.

The present invention is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems) and computer program products according to embodiments of the invention. It will be understood that each flow and/or block of the flowchart illustrations and/or block diagrams, and combinations of flows and/or blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

What is not described in detail in this specification is prior art known to those skilled in the art.

Claims (10)

1. A power and chassis fusion torque architecture based on electric four-wheel drive, comprising: a driving demand torque calculation module, a shaft demand torque calculation module, a wheel demand torque calculation module, and a motor demand torque calculation module;

The driving demand torque calculation module is used for calculating driving demand torque according to manual driving, automatic driving and vehicle longitudinal auxiliary driving arbitration;

the axle demand torque calculation module is used for calculating front axle demand torque and rear axle demand torque according to driving demand torque;

The wheel required torque calculation module is used for calculating the wheel required torque of each wheel according to the front axle required torque and the rear axle required torque;

The motor demand torque calculation module is configured to calculate a final motor demand torque according to the wheel demand torque of each wheel.

2. The electric four-wheel drive based power and chassis fusion torque architecture of claim 1, wherein the calculated driving demand torque calculation module is further configured to:

determining a driving torque distribution coefficient K1 and a driving torque arbitration coefficient K2 according to manual driving, automatic driving and vehicle longitudinal auxiliary driving arbitration;

and carrying out weighted calculation on the initial driving torque and the arbitrated driving torque according to the driving torque distribution coefficient K1 and the driving torque arbitration coefficient K2 to obtain driving demand torque.

3. The electric four-wheel drive power and chassis fusion based torque architecture of claim 2, wherein the method of determining the driving torque distribution coefficient K1 and the driving torque arbitration coefficient K2 comprises:

when the manual driving is started and the auxiliary driving function is not started, K1 is a first set value, and K2 is a second set value;

when manual driving is started and auxiliary driving works, K1 is a value which changes according to the vehicle speed, and K2 is a second set value;

When the automatic driving or constant speed cruising function is operated or the longitudinal stable torque control is enabled, K1 is a second set value, and K2 is a first set value.

4. The electric four-wheel drive power and chassis fusion based torque architecture of claim 1, wherein the axle demand torque calculation module is further configured to:

determining a front axle torque arbitration coefficient K4 according to the enabling state of the front axle longitudinal stability function; weighting calculation is carried out on driving demand torque and front axle arbitration torque according to a set axle torque distribution coefficient K3 and a front axle torque arbitration coefficient K4 to obtain front axle demand torque;

the front axle torque arbitration coefficient K4 is used to indicate whether the front axle longitudinal stability function is on.

5. The electric four-wheel drive based power and chassis fusion torque architecture of claim 1 or 4, wherein the axle demand torque calculation module is further configured to:

Determining a rear axle torque arbitration coefficient K5 according to the enabling state of the rear axle longitudinal stability function; weighting calculation is carried out on driving demand torque and rear axle arbitration torque according to a set axle torque distribution coefficient K3 and a rear axle torque arbitration coefficient K5 to obtain rear axle demand torque;

The rear axle torque arbitration coefficient K5 is used for indicating whether a rear axle longitudinal stability function is started or not; the rear axle arbitration torque is a torque obtained after arbitration according to economical distribution, dynamic distribution and vehicle longitudinal torque control.

6. The electric four-wheel drive based power and chassis fusion torque architecture of claim 1, wherein the wheel demand torque calculation module is further configured to:

Obtaining a front left wheel torque distribution coefficient K6 and a rear left wheel torque distribution coefficient K7 according to the vehicle slip state and the vehicle turning capacity;

Obtaining a front left wheel torque arbitration coefficient K8 and a front right wheel torque arbitration coefficient K9 according to the enabling state of the tire lateral stability function;

the front axle required torque and the front left wheel arbitration torque are weighted according to the front left wheel torque distribution coefficient K6 and the front left wheel torque arbitration coefficient K8 to obtain the front left wheel required torque;

and carrying out weighted calculation on the front axle required torque and the front right wheel arbitration torque according to the front left wheel torque distribution coefficient K6 and the front right wheel torque arbitration coefficient K9 to obtain the front right wheel required torque.

7. The electric four-wheel drive based power and chassis fusion torque architecture of claim 1 or 6, wherein the wheel demand torque calculation module is further configured to:

Obtaining a front left wheel torque distribution coefficient K6 and a rear left wheel torque distribution coefficient K7 according to the vehicle slip state and the vehicle turning capacity;

Obtaining a rear left wheel torque arbitration coefficient K10 and a rear right wheel torque arbitration coefficient K11 according to the enabling state of the tire lateral stability function;

Weighting calculation is carried out on the rear axle required torque and the rear left wheel arbitration torque according to the rear left wheel torque distribution coefficient K7 and the rear left wheel torque arbitration coefficient K10 to obtain the rear left wheel required torque;

And carrying out weighted calculation on the rear axle required torque and the rear right wheel arbitration torque according to the rear left wheel torque distribution coefficient K7 and the rear right wheel torque arbitration coefficient K11 to obtain the rear right wheel required torque.

8. The electric four-wheel drive power and chassis fusion based torque architecture of claim 1, wherein the electric machine demand torque calculation module is further configured to:

obtaining a motor torque arbitration coefficient K12 according to the enabling state of the anti-shake function of the motor;

Carrying out weighted calculation on wheel demand torque and arbitration motor torque according to a motor torque arbitration coefficient K12 to obtain final motor demand torque; the wheel demand torque is the calculated wheel demand torque of the wheel corresponding to the final motor; the motor torque is motor demand torque obtained by arbitration according to the vehicle shaking state.

9. A method for distributing torque based on electric four-wheel drive power and chassis fusion by adopting the torque architecture as claimed in claim 1, which is characterized in that:

Calculating driving demand torque according to manual driving, automatic driving and vehicle longitudinal auxiliary driving arbitration;

Calculating a front axle required torque and a rear axle required torque according to the driving required torque;

Calculating a wheel demand torque for each wheel from the front axle demand torque and the rear axle demand torque;

And calculating the final motor torque according to the wheel demand torque of each wheel.

10. A non-transitory computer readable storage medium having stored thereon a computer program, which when executed by a processor, implements the steps of the electric four-wheel drive based power and chassis fusion torque distribution method according to claim 9.