WO2024259993A1 - Braking energy recovery control method and apparatus, control system, vehicle, and medium - Google Patents

Abstract

A braking energy recovery control method, comprising: when a vehicle satisfies a preset energy recovery condition, determining a required braking torque on the basis of a pre-stored correspondence between a moving depth and a braking torque of a braking pedal of the vehicle; on the basis of a preset priority distribution motor braking torque principle, an energy recovery maximum torque limit value and the required braking torque, determining an expected motor braking torque and an expected hydraulic braking torque; and on the basis of the expected motor braking torque, the real-time rotating speed and efficiency of a front-wheel drive motor of the vehicle, and the real-time rotating speed and efficiency of a rear-wheel drive motor of the vehicle, determining a target distribution ratio that maximizes the sum of recovery power of the front-wheel drive motor and recovery power of the rear-wheel drive motor. In this way, torque distribution of the front-wheel drive motor and the rear-wheel drive motor based on the target distribution ratio is conducive to performing braking energy recovery with maximum power, so as to increase the braking energy recovery efficiency. In addition, the present invention further relates to a braking energy recovery apparatus, a control system, a vehicle, and a medium.

Description

Braking energy recovery control method, device, control system, vehicle and medium

This application claims the priority of the Chinese patent application filed with the China Patent Office on June 20, 2023, with application number 202310735961.6 and application name “Braking Energy Recovery Control Method, Device, Control System, Vehicle and Medium”, all contents of which are incorporated by reference in this application.

Technical Field

The present application relates to the field of vehicle braking technology, and in particular to a braking energy recovery control method, device, control system, vehicle and medium.

Background Art

As the global energy crisis and environmental problems become increasingly severe, hybrid vehicles are becoming more and more popular among the public. As one of the key technologies of hybrid vehicles, brake energy recovery can effectively reduce the fuel consumption of hybrid vehicles, improve fuel economy, and increase the pure electric range of vehicles.

At present, there are solutions for braking energy recovery, but the efficiency of energy recovery still needs to be improved. For example, in the Chinese patent with publication number CN102897041B, a method for distributing regenerative braking torque in a four-wheel drive hybrid system is disclosed. Among them, the vehicle controller controls the braking energy recovery according to various data parameters of the ISG (Integrated Starter Generator) motor, the rear drive motor and the ABS (Anti-lock Braking System), as well as the vehicle speed information, the vehicle gear information, the accelerator pedal amplitude information and the brake pedal information received through data acquisition. However, the content disclosed in the patent focuses on the control of braking energy recovery when there is a partial fault in the vehicle, and does not mention the method of distributing the braking energy recovery torque when the system is normal, and cannot ensure the maximum efficiency of braking energy recovery.

Summary of the invention

In view of this, the purpose of the embodiments of the present application is to provide a braking energy recovery control method, device, control system, vehicle and medium, which can help the vehicle to achieve braking energy recovery with maximum efficiency.

In order to achieve the above technical objectives, the technical solutions adopted in this application are as follows:

In a first aspect, an embodiment of the present application provides a braking energy recovery control method, the method comprising:

When the vehicle meets the preset energy recovery condition, based on the pre-stored correspondence between the movement depth of the brake pedal of the vehicle and the braking torque, determine the required braking torque T _TotBrk corresponding to the current movement depth of the brake pedal when performing the braking operation;

Based on the preset principle of prioritizing the allocation of electric motor torque, the maximum torque limit value T _Max of energy recovery and the required braking torque T _TotBrk , the expected electric motor torque T _MtrBrk and the expected hydraulic braking torque T _MecBrk are determined, and T _TotBrk =T _MtrBrk +T _MecBrk , and the expected electric motor torque T _MtrBrk ≤T _Max ;

Determining a target allocation ratio that maximizes the sum of the regenerative power of the front motor and the regenerative power of the rear motor based on the desired motor torque T _MtrBrk , the real-time speed n _Front and efficiency η _Front of the front motor of the vehicle, and the real-time speed n _Rear and efficiency η _Rear of the rear motor of the vehicle;

Determining a desired braking torque T _Front of the front drive motor and a desired braking torque T _Rear of the rear drive motor based on the target distribution ratio and the desired motor braking torque T _MtrBrk ;

Based on the expected braking torque T _Front of the front drive motor and the expected braking torque T _Rear of the rear drive motor, the front drive motor and the rear drive motor are respectively controlled to perform energy recovery, and based on the expected hydraulic braking torque T _MecBrk, the hydraulic brake mechanism of the vehicle is controlled to perform braking.

In combination with the first aspect, in some optional implementations, based on the preset principle of prioritizing the allocation of electric motor braking torque, the energy recovery maximum torque limit T _Max and the required braking torque T _TotBrk , determining the expected electric motor braking torque T _MtrBrk and the expected hydraulic braking torque T _MecBrk includes:

When the required braking torque T _TotBrk is greater than the maximum torque limit T _Max , the expected motor braking torque T _MtrBrk =T _Max and the expected hydraulic braking torque T _MecBrk =T _TotBrk -T _Max are determined;

When the required braking torque T _TotBrk is less than or equal to the maximum torque limit T _Max , it is determined that the expected motor braking torque T _MtrBrk =T _TotBrk and the expected hydraulic braking torque T _MecBrk =0.

In combination with the first aspect, in some optional implementations, based on the expected motor torque T _MtrBrk , the real-time speed n _Front and efficiency η _Front of the front motor, and the real-time speed n _Rear and efficiency η _Rear of the rear motor, a target allocation ratio that maximizes the sum of the regenerated power of the front motor and the regenerated power of the rear motor is determined, including:

Based on the preset value range of the allocation ratio, multiple groups of allocation ratios r _Front and r _Rear are selected from the preset value range according to the preset gradient, wherein r _Front refers to the allocation ratio of the front drive motor, and r _Rear refers to the allocation ratio of the rear drive motor. In the same group of allocation ratios, the sum of r _Front and r _Rear is 100%;

Determine the total recovery power under each allocation ratio according to the expected braking torque T _Front , the expected braking torque T _Rear , the real-time speed n _Front and efficiency η _Front of the front drive motor, and the real-time speed n _Rear and efficiency η _Rear of the rear drive motor;

From the total recovery power of each group of allocation ratios under the multiple groups of allocation ratios, the allocation ratio corresponding to the maximum total recovery power is selected as the target allocation ratio.

In combination with the first aspect, in some optional embodiments, the preset value range is 0 to 100%, the preset gradient is 1%, and the values of each group in the multiple groups of allocation ratios (r _Front , r _Rear ) are respectively (0, 100%), (1%, 99%), …, (100%, 0).

In combination with the first aspect, in some optional implementations, the method further includes:

Obtaining the actual braking torque T _ActF of the front drive motor and the actual braking torque T _ActR of the rear drive motor, and obtaining the sum of the actual braking torques T _ActTot =T _ActF +T _ActR ;

When the desired electric braking torque T _MtrBrk >T _ActTot , the hydraulic brake mechanism is controlled to compensate for the insufficient electric braking torque T _BrkDif =T _MtrBrk -T _ActTot ;

When the desired motor braking torque T _MtrBrk ≤T _ActTot and the desired hydraulic braking torque T _MecBrk ≥T _ActTot -T _MtrBrk , the hydraulic brake mechanism is controlled to reduce the output of the desired motor braking torque T _MtrBrk based on the exceeded motor braking torque T _ActTot -T _MtrBrk .

In combination with the first aspect, in some optional implementations, before determining the required braking torque T TotBrk corresponding to the current moving depth of the brake pedal when performing a braking operation based on a pre-stored correspondence between the moving depth of the brake pedal of the vehicle and the braking _torque , the method further includes:

Acquire a vehicle status data set, the status data set including the gear information, vehicle speed, first status information of the front drive motor, second status information of the rear drive motor, third status information of the power battery, and fourth status information of the brake system. Status information;

Based on the status data set, determine whether the vehicle meets the energy recovery condition, wherein when the gear information indicates that the vehicle is in a forward gear, and the vehicle speed exceeds a preset rate, and the third status information indicates that the power battery has no fault, and the fourth status information indicates that the braking system has no fault, and the first status information indicates that the front drive motor has no fault or the second status information indicates that the rear drive motor has no fault, it is determined that the energy recovery condition is met.

In combination with the first aspect, in some optional implementations, before determining the required braking torque T TotBrk corresponding to the current moving depth of the brake pedal when performing a braking operation based on a pre-stored correspondence between the moving depth of the brake pedal of the vehicle and the braking _torque , the method further includes:

Obtaining the maximum recovery torque T _MaxF of the front drive motor, the maximum recovery torque T _MaxR of the rear drive motor, and the maximum charging power P _BatMax of the power battery on the vehicle;

The maximum torque limit T _Max for motor braking is determined based on the maximum regenerative torque T _MaxF , the maximum regenerative torque T _MaxR and the maximum charging power P _BatMax , wherein T _Max =min(T _MaxF +T _MaxR ,9550P _BatMax /n), and n refers to the equivalent motor speed of the vehicle at the current vehicle speed.

In a second aspect, an embodiment of the present application further provides a braking energy recovery control device, the device comprising:

A first determining unit, configured to determine, when the vehicle meets a preset energy recovery condition, a required braking torque T TotBrk corresponding to a current moving depth of the brake pedal when the brake pedal performs a braking operation based on a pre-stored correspondence between the moving depth of the brake pedal of the vehicle and the braking _torque ;

a second determining unit, configured to determine a desired electric motor braking torque T _MtrBrk and a desired hydraulic braking torque T _MecBrk based on a preset principle of prioritizing the allocation of electric motor braking torque, a maximum energy recovery torque limit T _Max , and the required braking torque T _TotBrk , and to satisfy T _TotBrk =T _MtrBrk +T _MecBrk , and the desired electric motor braking torque T _MtrBrk ≤T _Max ;

a third determining unit, configured to determine a target allocation ratio for maximizing the sum of the regenerative power of the front drive motor and the regenerative power of the rear drive motor based on the desired motor torque T _MtrBrk , the real-time speed n _Front and efficiency η _Front of the front drive motor of the vehicle, and the real-time speed n _Rear and efficiency η _Rear of the rear drive motor of the vehicle;

a fourth determining unit, configured to determine an expected braking torque T _Front of the front drive motor and an expected braking torque T _Rear of the rear drive motor based on the target distribution ratio and the expected motor braking torque T _MtrBrk ;

The control unit is used to control the front drive motor and the rear drive motor to perform energy recovery based on the expected braking torque T _Front of the front drive motor and the expected braking torque T _Rear of the rear drive motor, and to control the hydraulic brake mechanism of the vehicle to brake based on the expected hydraulic braking torque T _MecBrk .

In a third aspect, an embodiment of the present application further provides a control system, which includes a processing module and a storage module coupled to each other, wherein a computer program is stored in the storage module, and when the computer program is executed by the processing module, the control system executes the above method.

In conjunction with the third aspect, in some optional implementations, the control system further includes:

A battery management system, a brake system and a brake pedal, wherein the processing module is electrically connected to sensors in the battery management system, the brake system and the brake pedal.

In conjunction with the third aspect, in some optional implementations, the processing module includes: a powertrain controller, a front drive motor controller, a rear drive motor controller, and a gear controller;

The powertrain controller is used to receive a signal set from the front drive motor controller, the rear drive motor controller, the battery management system, the brake system, the brake pedal and the gear controller, and integrate the signal set. Signal set to control brake energy recovery.

In a fourth aspect, an embodiment of the present application further provides a vehicle, comprising a vehicle body and the above-mentioned control system, wherein the control system is disposed on the vehicle body.

In a fifth aspect, an embodiment of the present application further provides a computer-readable storage medium, wherein a computer program is stored in the computer-readable storage medium. When the computer program runs on a computer, the computer executes the above method.

In a sixth aspect, an embodiment of the present application further provides a computer program, comprising a program code, and when a computer runs the computer program, the program code executes the above method.

The application using the above technical solution has the following advantages:

In the technical solution provided in the present application, when the vehicle meets the preset energy recovery conditions, the required braking torque T _TotBrk corresponding to the current moving depth of the brake pedal when performing the braking operation is calculated, so that the reliability and safety of the braking energy recovery can be improved; then based on the preset principle of priority allocation of electric motor braking torque, the maximum torque limit T _Max of energy recovery and the required braking torque T _TotBrk , the expected electric motor braking torque T _MtrBrk and the expected hydraulic braking torque T _MecBrk are determined, and the target allocation ratio that maximizes the sum of the recovery power of the front drive motor and the recovery power of the rear drive motor is calculated, and based on the expected braking torque T _Front of the front drive motor and the expected braking torque T _Rear of the rear drive motor, the front drive motor and the rear drive motor are respectively controlled to recover energy, and the hydraulic brake mechanism of the vehicle is controlled to brake based on the expected hydraulic braking torque T _MecBrk . In this way, the torque distribution of the front drive motor and the rear drive motor based on the target allocation ratio is conducive to braking energy recovery with maximum power, which can improve the efficiency of braking energy recovery.

BRIEF DESCRIPTION OF THE DRAWINGS

The present application may be further described by the non-limiting embodiments given in the accompanying drawings. It should be understood that the following drawings only illustrate certain embodiments of the present application and therefore should not be regarded as limiting the scope. For those of ordinary skill in the art, other relevant drawings may be obtained based on these drawings without creative effort.

FIG. 1 is a block diagram of a control system provided in an embodiment of the present application.

FIG2 is a flow chart of a braking energy recovery control method provided in an embodiment of the present application.

FIG3 is a control logic flow diagram of a braking energy recovery control method provided in an embodiment of the present application.

Icons: 10-control system; 11-powertrain controller; 12-front drive motor controller; 13-rear drive motor controller; 14-battery management system; 15-brake system; 16-accelerator pedal; 17-brake pedal; 18-gear controller.

DETAILED DESCRIPTION

The present application will be described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that in the drawings or descriptions, similar or identical parts use the same figure numbers, and the implementation methods not shown or described in the drawings are forms known to ordinary technicians in the relevant technical field. In the description of this application, the terms "first", "second", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

Referring to Fig. 1, an embodiment of the present application provides a control system 10, which may include a processing module and a storage module. The storage module stores a computer program, and when the computer program is executed by the processing module, the control system 10 can perform the corresponding steps in the following braking energy recovery control method.

The control system 10 can be deployed in a four-wheel drive hybrid vehicle, or in an electric vehicle including at least four drive motors. The application scenario of the control system 10 is not specifically limited. The drive motor in the vehicle performs brake energy recovery control.

In this embodiment, the control system 10 may also include: a battery management system 14, a braking system 15, an accelerator pedal 16 and a brake pedal 17, and the processing module is electrically connected to the battery management system 14, the braking system 15, the sensors in the accelerator pedal 16, and the sensors in the brake pedal 17.

The processing module may include: a powertrain controller 11 , a front drive motor controller 12 , a rear drive motor controller 13 and a gear controller 18 .

The powertrain controller 11 is used to receive signal sets from the front drive motor controller 12, the rear drive motor controller 13, the battery management system 14, the braking system 15, the brake pedal 17 and the gear controller 18, and integrate the signal sets to control the braking energy recovery.

Understandably, the powertrain controller 11 can calculate the maximum torque limit T _Max of the braking energy recovery according to the signal set, distribute the motor braking torque T _MtrBrk of the braking system 15 to the front and rear axles, and respectively control the front drive motor controller 12 and the rear drive motor controller 13 to execute the corresponding requested torque.

The front drive motor controller 12 may receive a signal from the powertrain controller 11 , and execute the front drive motor braking torque T _Front , and feed back the actually executed front drive motor braking torque T _ActF .

The rear-drive motor controller 13 may receive a signal from the powertrain controller 11 , and execute the rear-drive motor braking torque T _Rear , and feed back the rear-drive motor braking torque T _ActR actually executed.

The braking system 15 can receive signals from the powertrain controller 11 and the sensors of the brake pedal 17, and calculate the required braking torque T _TotBrk of the driver/vehicle according to the movement depth collected by the sensors of the brake pedal 17, and distribute the electric braking torque T _MtrBrk and the hydraulic braking torque T _MecBrk according to the maximum torque limit T _Max of the braking energy recovery of the powertrain controller 11. When the actual electric braking torque is insufficient, the hydraulic braking mechanism in the braking system 15 needs to be controlled to compensate.

The gear controller 18 can be used to obtain gear status information, such as forward gear, reverse gear and other information.

In this embodiment, the storage module may be, but is not limited to, a random access memory, a read-only memory, a programmable read-only memory, an erasable programmable read-only memory, an electrically erasable programmable read-only memory, etc. In this embodiment, the storage module may be used to store preset energy recovery conditions, vehicle gear information, vehicle speed, first state information of the front drive motor, second state information of the rear drive motor, third state information of the power battery, and fourth state information of the brake system 15, etc. Of course, the storage module may also be used to store a program, and the processing module executes the program after receiving the execution instruction.

It is understandable that the control system 10 structure shown in Figure 1 is only a schematic diagram of the structure, and the control system 10 may also include more or fewer components than those shown in Figure 1. Each component shown in Figure 1 may be implemented by hardware, software or a combination thereof.

It should be noted that technicians in the relevant field can clearly understand that for the convenience and simplicity of description, the specific working process of the control system 10 described above can refer to the corresponding process of each step in the following braking energy recovery control method, and will not be elaborated here.

Referring to FIG. 2 , the present application further provides a braking energy recovery control method, which can be applied to the above-mentioned control system 10, and each step of the method is executed or implemented by the control system 10. The braking energy recovery control method can include the following steps:

Step 110, when the vehicle meets the preset energy recovery condition, based on the pre-stored correspondence between the movement depth of the brake pedal of the vehicle and the braking torque, determining the required braking torque T _TotBrk corresponding to the current movement depth of the brake pedal when performing the braking operation;

Step 120, based on the preset principle of prioritizing the allocation of electric motor torque, the maximum torque limit value T _Max of energy recovery and the required braking torque T _TotBrk , determine the expected electric motor torque T _MtrBrk and the expected hydraulic braking torque T _MecBrk , and satisfy T _TotBrk =T _MtrBrk +T _MecBrk , and the expected electric motor torque T _MtrBrk ≤T _Max ;

Step 130, determining a target allocation ratio that maximizes the sum of the regenerative power of the front drive motor and the regenerative power of the rear drive motor based on the desired motor torque T _MtrBrk , the real-time speed n _Front and efficiency η _Front of the front drive motor of the vehicle, and the real-time speed n _Rear and efficiency η _Rear of the rear drive motor of the vehicle;

Step 140, determining the expected braking torque T _Front of the front drive motor and the expected braking torque T _Rear of the rear drive motor based on the target allocation ratio and the expected motor braking torque T _MtrBrk ;

Step 150 : Based on the expected braking torque T _Front of the front drive motor and the expected braking torque T _Rear of the rear drive motor, respectively control the front drive motor and the rear drive motor to perform energy recovery, and based on the expected hydraulic braking torque T _MecBrk control the hydraulic brake mechanism of the vehicle to perform braking.

The following will be combined with Figures 2 and 3 to describe in detail the various steps of the braking energy recovery control method, as follows:

Before step 110, the method may further include a step of detecting whether the vehicle meets a preset energy recovery condition. For example, before step 110, the method may further include:

Acquire a state data set of the vehicle, the state data set including gear information, vehicle speed, first state information of the front drive motor, second state information of the rear drive motor, third state information of the power battery, and fourth state information of the braking system of the vehicle;

According to the state data set, determining whether the vehicle meets the energy recovery condition, wherein when the gear information indicates that the vehicle is in a forward gear, and the vehicle speed exceeds a preset rate, and the third state information indicates that the power battery has no fault, and the fourth state information indicates that the brake system has no fault, and the first state information indicates that the front drive motor has no fault or the second state information indicates that the rear drive motor has no fault, it is determined that the energy recovery condition is met;

When the gear information indicates that the vehicle is not in the forward gear, or the vehicle speed does not exceed the preset rate, or the third state information indicates that the power battery is faulty, or the fourth state information indicates that the braking system is faulty, or the first state information indicates that the front drive motor is faulty and the second state information indicates that the rear drive motor is faulty, it is determined that the energy recovery condition is not met.

Please refer to FIG. 3 again. In this embodiment, the state data set is obtained in a conventional manner. For example, the powertrain controller can obtain the gear information from the gear controller of the vehicle, obtain the vehicle speed from the instrument panel of the vehicle, obtain the first state information of the front drive motor from the front drive motor controller, obtain the second state information of the rear drive motor from the rear drive motor controller, obtain the third state information of the power battery from the battery management system, and obtain the fourth state information of the brake system from the brake system. Various types of state information are used to indicate whether the current electronic device has a fault. For example, the first state information includes information indicating whether the front drive motor has a fault or not.

In this embodiment, the preset rate is a relatively low vehicle speed, which can be flexibly set according to actual conditions, for example, the preset rate can be 2 km/h. The control system can comprehensively determine whether the energy recovery conditions are met by collecting various data of the vehicle, which is conducive to improving the safety and reliability of subsequent energy recovery and avoiding safety hazards caused by braking energy recovery when the energy recovery conditions are not met. For example, if braking energy recovery is still performed after a power battery failure, it is easy to cause further damage to the power battery, thereby affecting driving safety.

Before step 110, the method may further include the step of calculating the maximum recovery torque T _MaxF of the motor braking energy recovery. For example, before step 110, the method may further include:

Obtaining the maximum recovery torque T _MaxF of the front drive motor, the maximum recovery torque T _MaxR of the rear drive motor, and the maximum charging power P _BatMax of the power battery on the vehicle;

The maximum torque limit T _Max for motor braking is determined based on the maximum recovery torque T _MaxF , the maximum recovery torque T _MaxR and the maximum charging power P _BatMax , wherein T _Max =min(T _MaxF +T _MaxR ,9550P _BatMax /n), and n refers to the equivalent motor speed of the vehicle at the current vehicle speed. n can be flexibly determined according to actual conditions. When the vehicle speed is very low (for example, the vehicle speed is less than 5 km/h), n can be a preset value.

Understandably, the maximum recovery torque T _MaxF of the front drive motor, the maximum recovery torque T _MaxR of the rear drive motor, and the maximum charging power P _BatMax of the power battery are usually pre-calibrated values and can be pre-stored in the storage module. The control system can obtain the maximum recovery torque T _MaxF of the front drive motor, the maximum recovery torque T _MaxR of the rear drive motor, and the maximum charging power P _BatMax of the power battery locally.

In this embodiment, the maximum torque limit T _Max of the motor brake can be calculated by the formula T _Max =min(T _MaxF +T _MaxR , 9550P _BatMax /n). In this way, the calculated expected motor braking torque T _MtrBrk can be avoided from exceeding the sum of the maximum output torques of the front drive motor and the rear drive motor, and the expected motor braking torque T _MtrBrk can be avoided from exceeding the torque corresponding to the maximum charging power P _BatMax of the power battery, thereby causing the charging power to be excessive. Excessive charging power can easily damage the power battery.

In step 110, the control system may pre-store and record the corresponding relationship between the movement depth of the brake pedal and the braking torque, and the corresponding relationship may be a relationship table or a relationship curve, that is, different movement depths correspond to different braking torques. When the current movement depth during the braking operation is collected by the sensor of the brake pedal, the powertrain controller may obtain the braking torque corresponding to the current movement depth based on the corresponding relationship as the required braking torque T _TotBrk .

In step 120 , based on the preset principle of prioritizing the electric motor braking torque, the energy recovery maximum torque limit T _Max and the required braking torque T _TotBrk , the desired electric motor braking torque T _MtrBrk and the desired hydraulic braking torque T _MecBrk are determined, which may include:

When the required braking torque T _TotBrk is greater than the maximum torque limit T _Max , the expected motor braking torque T _MtrBrk =T _Max and the expected hydraulic braking torque T _MecBrk =T _TotBrk -T _Max are determined;

When the required braking torque T _TotBrk is less than or equal to the maximum torque limit T _Max , it is determined that the expected motor braking torque T _MtrBrk =T _TotBrk and the expected hydraulic braking torque T _MecBrk =0.

In this embodiment, the principle of prioritizing the allocation of the motor braking torque can be understood as follows: before the required braking torque T _TotBrk reaches the maximum torque limit T _Max , the required braking torque T _TotBrk is fully allocated to the motor (the front drive motor and/or the rear drive motor), and at this time, no torque is allocated to the hydraulic braking mechanism; when the required braking torque T _TotBrk exceeds the maximum torque limit T _Max , the quota torque of the motor is fully allocated, that is, the expected motor braking torque T _MtrBrk = T _Max , and then the torque exceeding the maximum torque limit T _Max is allocated to the hydraulic braking mechanism as the hydraulic braking torque.

In this embodiment, step 130 may include:

Based on the preset value range of the allocation ratio, multiple groups of allocation ratios r _Front and r _Rear are selected from the preset value range according to the preset gradient, wherein r _Front refers to the allocation ratio of the front drive motor, and r _Rear refers to the allocation ratio of the rear drive motor. In the same group of allocation ratios, the sum of r _Front and r _Rear is 100%;

Determine the total recovery power under each allocation ratio according to the expected braking torque T _Front , the expected braking torque T _Rear , the real-time speed n _Front and efficiency η _Front of the front drive motor, and the real-time speed n _Rear and efficiency η _Rear of the rear drive motor;

From the total recovery power of each group of allocation ratios under the multiple groups of allocation ratios, select the distribution ratio corresponding to the maximum total recovery power. The target allocation ratio is used as the target allocation ratio.

It can be understood that the smaller the preset gradient is, the more groups of distribution ratios are divided, and the greater the maximum total recovery power of the calculated target distribution ratio is.

As an example, the preset value range is 0 to 100%, and the preset gradient is 1%. At this time, a total of 101 groups of distribution ratios (r _Front , r _Rear ) can be obtained. In each group of distribution ratios, r _Front refers to the percentage of the torque of the front drive motor, and r _Rear refers to the percentage of the torque of the rear drive motor, and satisfies r _Front +r _Rear = 100%. The values of each group can be (0, 100%), (1%, 99%), ..., (100%, 0). Then, the front drive motor recovery power _PiFront and the rear drive motor recovery power _PiRear corresponding to each group of allocation ratios are calculated respectively, where i represents the group number of the allocation ratio, and i can be 0 to 100 in sequence. Then, through the formula max( _P0Front + _P0Rear ,…, _PiFront + _PiRear ,…, _P100Front + _P100Rear ), the group of allocation ratios with the largest recovery power is calculated as the target allocation ratio ( _rFrontPmax , _rRearPmax ).

In step 140, the powertrain controller can calculate the expected braking torque T _{Front =T MtrBrk *r FrontPmax of the front drive motor and the expected braking torque T Rear = T MtrBrk} *r _RearPmax =T _MtrBrk -T _Front of the rear drive motor based on the target distribution ratio (r _FrontPmax , r _RearPmax ) and the expected motor _braking torque T _MtrBrk , and send the expected braking torque T _Fron of the front drive motor and the expected braking torque T _Rear of the rear drive motor to the front drive motor controller and the rear drive motor controller, respectively, to perform torque control of the corresponding motors in step 150.

In step 150, the front motor controller can control the front motor to operate based on the expected braking torque _TFront so that the torque output by the front motor is the same as or close to the expected braking torque _TFront for braking energy recovery. If the expected braking torque _TFront is 0, there is no need to control the front motor to perform braking energy recovery.

The rear drive motor controller can control the rear drive motor to operate based on the expected braking torque T _Rear , so that the torque output by the rear drive motor is the same as or close to the expected braking torque T _Rear , so as to perform braking energy recovery. If the expected braking torque T _Rear is 0, there is no need to control the rear drive motor to perform braking energy recovery.

The brake system can control the operation of the hydraulic brake mechanism based on the expected hydraulic braking torque T _MecBrk so that the torque output by the hydraulic brake mechanism is the same as or close to the expected hydraulic braking torque T _MecBrk . If the expected hydraulic braking torque T _MecBrk is 0, there is no need to control the hydraulic brake mechanism to perform the braking operation.

In this embodiment, the method may further include:

Obtaining the actual braking torque T _ActF of the front drive motor and the actual braking torque T _ActR of the rear drive motor, and obtaining the sum of the actual braking torques T _ActTot =T _ActF +T _ActR ;

When the desired electric braking torque T _MtrBrk >T _ActTot , the hydraulic brake mechanism is controlled to compensate for the insufficient electric braking torque T _BrkDif =T _MtrBrk -T _ActTot ;

When the desired motor braking torque T _MtrBrk ≤T _ActTot and the desired hydraulic braking torque T _MecBrk ≥T _ActTot -T _MtrBrk , the hydraulic brake mechanism is controlled to reduce the output of the desired motor braking torque T _MtrBrk based on the exceeded motor braking torque T _ActTot -T _MtrBrk .

Please refer to Figure 3 again. It can be understood that the front-drive motor controller and the rear-drive motor controller can provide real-time feedback of the actual braking torque T _ActF performed by the front-drive motor and the actual braking torque T _ActR of the rear-drive motor to the braking system. When the braking system determines that the sum of the braking torques provided by the front-drive motor and the rear-drive motor T _ActTot = T _ActF + T _ActR does not meet the expected electric braking torque T _MtrBrk , the braking system needs to control the hydraulic braking mechanism to compensate for the insufficient electric braking torque T _BrkDif = T _MtrBrk - _{T ActTot} .

In addition, when the hydraulic brake mechanism also participates in braking, and the sum of the braking torques provided by the front drive motor and the rear drive motor exceeds the expected motor braking torque T _MtrBrk , and the expected hydraulic braking torque T _MecBrk ≥ T _ActTot -T _MtrBrk , the expected The output of the hydraulic braking torque reduces the torque by ΔT=T _ActTot -T _MtrBrk , thereby preventing the front drive motor and the rear drive motor from outputting excessive torque, thereby preventing the braking stability of the vehicle from being affected.

Based on the above design, the powertrain controller or the processor in the braking system calculates the driver's braking torque demand and distributes the electric braking torque and the hydraulic braking torque, which not only ensures the braking safety of the vehicle, but also maximizes the recovery of braking energy; the powertrain controller calculates the maximum distribution ratio of the recovered power based on the expected electric braking torque, the speed and efficiency of the front/rear drive motors and different distribution ratios, and distributes the front and rear electric braking torques, which is conducive to energy recovery with the maximum recovery power, can increase the energy of the braking energy recovery of the four-wheel drive hybrid system, and further improve the efficiency of energy recovery.

The embodiment of the present application also provides a braking energy recovery control device, which includes at least one software function module that can be stored in a storage module or fixed in an operating system (OS) in the form of software or firmware. The processing module is used to execute the executable module stored in the storage module, such as the software function module and computer program included in the braking energy recovery control device.

The braking energy recovery control device includes, and the functions of each unit may be as follows:

A first determining unit, configured to determine, when the vehicle meets a preset energy recovery condition, a required braking torque T TotBrk corresponding to a current moving depth of the brake pedal when the brake pedal performs a braking operation based on a pre-stored correspondence between the moving depth of the brake pedal of the vehicle and the braking _torque ;

a second determining unit, configured to determine a desired electric motor braking torque T _MtrBrk and a desired hydraulic braking torque T _MecBrk based on a preset principle of prioritizing the allocation of electric motor braking torque, a maximum energy recovery torque limit T _Max , and the required braking torque T _TotBrk , and to satisfy T _TotBrk =T _MtrBrk +T _MecBrk , and the desired electric motor braking torque T _MtrBrk ≤T _Max ;

a third determining unit, configured to determine a target allocation ratio for maximizing the sum of the regenerative power of the front drive motor and the regenerative power of the rear drive motor based on the desired motor torque T _MtrBrk , the real-time speed n _Front and efficiency η _Front of the front drive motor of the vehicle, and the real-time speed n _Rear and efficiency η _Rear of the rear drive motor of the vehicle;

a fourth determining unit, configured to determine an expected braking torque T _Front of the front drive motor and an expected braking torque T _Rear of the rear drive motor based on the target distribution ratio and the expected motor braking torque T _MtrBrk ;

The control unit is used to control the front drive motor and the rear drive motor to perform energy recovery based on the expected braking torque T _Front of the front drive motor and the expected braking torque T _Rear of the rear drive motor, and to control the hydraulic brake mechanism of the vehicle to brake based on the expected hydraulic braking torque T _MecBrk .

Optionally, the second determining unit may be specifically configured to: when the required braking torque T _TotBrk is greater than the maximum torque limit T _Max , determine the expected motor braking torque T _MtrBrk =T _Max , the expected hydraulic braking torque T _MecBrk =T _TotBrk -T _Max ;

When the required braking torque T _TotBrk is less than or equal to the maximum torque limit T _Max , it is determined that the expected motor braking torque T _MtrBrk =T _TotBrk and the expected hydraulic braking torque T _MecBrk =0.

Optionally, the third determining unit may be specifically configured to:

Based on the preset value range of the allocation ratio, multiple groups of allocation ratios r _Front and r _Rear are selected from the preset value range according to the preset gradient, wherein r _Front refers to the allocation ratio of the front drive motor, and r _Rear refers to the allocation ratio of the rear drive motor. In the same group of allocation ratios, the sum of r _Front and r _Rear is 100%;

Determine the total recovery power under each allocation ratio according to the expected braking torque T _Front , the expected braking torque T _Rear , the real-time speed n _Front and efficiency η _Front of the front drive motor, and the real-time speed n _Rear and efficiency η _Rear of the rear drive motor;

From the total recovery power of each group of allocation ratios under the multiple groups of allocation ratios, the allocation ratio corresponding to the maximum total recovery power is selected as the target allocation ratio.

Optionally, the braking energy recovery control device may further include a first acquisition unit. The first acquisition unit is used to acquire the actual braking torque T _ActF of the front drive motor and the actual braking torque T _ActR of the rear drive motor, and obtain the sum of the actual braking torques T _ActTot = T _ActF + T _ActR ;

The control unit can also be used to: when the expected electric motor braking torque T _MtrBrk ＞T _ActTot , control the hydraulic braking mechanism to compensate for the insufficient compensation electric braking torque T _BrkDif ＝T _MtrBrk -T _ActTot ; and when the expected electric motor braking torque T _MtrBrk ≤T _ActTot and the expected hydraulic braking torque T _MecBrk ≥T _ActTot -T _MtrBrk , control the hydraulic braking mechanism to reduce the output of the expected electric motor braking torque T _MtrBrk based on the exceeded electric motor braking torque T _ActTot -T _MtrBrk .

Optionally, the braking energy recovery control device may further include a second acquisition unit and a judgment unit. Before determining the required braking torque T _TotBrk corresponding to the current movement depth of the brake pedal when the brake pedal performs a braking operation based on the pre-stored correspondence between the movement depth of the brake pedal of the vehicle and the braking torque, the second acquisition unit is used to acquire a vehicle state data set, the state data set including the gear information, vehicle speed, first state information of the front drive motor, second state information of the rear drive motor, third state information of the power battery and fourth state information of the braking system of the vehicle;

The judgment unit is used to judge whether the vehicle meets the energy recovery condition based on the state data set, wherein when the gear information indicates that the vehicle is in a forward gear and the vehicle speed exceeds a preset rate, and the third state information indicates that the power battery has no fault, and the fourth state information indicates that the braking system has no fault, and the first state information indicates that the front drive motor has no fault or the second state information indicates that the rear drive motor has no fault, it is determined that the energy recovery condition is met.

Optionally, the braking energy recovery control device may further include a third acquisition unit and a fifth determination unit. Before determining the required braking torque T _TotBrk corresponding to the current movement depth of the brake pedal when the brake pedal performs a braking operation based on the pre-stored correspondence between the movement depth of the vehicle's brake pedal and the braking torque, the third acquisition unit is used to acquire the maximum recovery torque T _MaxF of the front drive motor, the maximum recovery torque T _MaxR of the rear drive motor, and the maximum charging power P _BatMax of the power battery on the vehicle; the fifth determination unit is used to determine the maximum torque limit T _Max for motor braking based on the maximum recovery torque T _MaxF , the maximum recovery torque T _MaxR and the maximum charging power P _BatMax , wherein T _Max =min(T _MaxF +T _MaxR , 9550P _BatMax /n), and n refers to the equivalent motor speed of the vehicle at the current vehicle speed.

It should be noted that technicians in the relevant field can clearly understand that for the convenience and simplicity of description, the specific working process of the braking energy recovery control device described above can refer to the corresponding process of each step in the braking energy recovery control method described below, and will not be elaborated here.

An embodiment of the present application also provides a vehicle, which may include a vehicle body and the above-mentioned control system, and the control system is deployed on the vehicle body. In this way, the vehicle has the functions of the above-mentioned control system, which is beneficial to improving the efficiency of braking energy recovery of the vehicle during braking.

The embodiment of the present application further provides a computer-readable storage medium. The computer-readable storage medium stores a computer program, and when the computer program is run on a computer, the computer executes the braking energy recovery control method described in the above embodiment.

An embodiment of the present application further provides a computer program, including a program code. When a computer runs the computer program, the program code executes the braking energy recovery control method as described in the above embodiment.

Through the description of the above implementation modes, those skilled in the art can clearly understand that the present application can be implemented by hardware or by means of software plus a necessary general hardware platform. Based on this understanding, the present application The technical solution can be embodied in the form of a software product, which can be stored in a non-volatile storage medium (which can be a CD-ROM (Compact Disc Read-Only Memory), a USB flash drive, a mobile hard disk, etc.), and includes a number of instructions for enabling a computer device (which can be a personal computer, a control system, or a network device, etc.) to execute the methods described in various implementation scenarios of the present application.

In the embodiments provided in the present application, it should be understood that the disclosed device, system and method can also be implemented in other ways. The above-described device, system and method embodiments are merely schematic, for example, the flowchart and block diagram in the accompanying drawings show the possible architecture, function and operation of the system, method and computer program product according to the multiple embodiments of the present application. In this regard, each box in the flowchart or block diagram can represent a part of a module, a program segment or a code, and a part of the module, program segment or code includes one or more executable instructions for implementing the specified logical function. It should also be noted that each box in the block diagram and/or the flowchart, and the combination of the boxes in the block diagram and/or the flowchart can be implemented by a dedicated hardware-based system that performs the specified function or action, or can be implemented by a combination of dedicated hardware and computer instructions. In addition, each functional module in each embodiment of the present application can be integrated together to form an independent part, or each module can exist separately, or two or more modules can be integrated to form an independent part.

The above description is only an embodiment of the present application and is not intended to limit the protection scope of the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims (14)

A braking energy recovery control method, characterized in that the method comprises: When the vehicle meets the preset energy recovery condition, based on the pre-stored correspondence between the movement depth of the brake pedal of the vehicle and the braking torque, determine the required braking torque T _TotBrk corresponding to the current movement depth of the brake pedal when performing the braking operation; Based on the preset principle of prioritizing the allocation of electric motor torque, the maximum torque limit value T _Max of energy recovery and the required braking torque T _TotBrk , the expected electric motor torque T _MtrBrk and the expected hydraulic braking torque T _MecBrk are determined, and T _TotBrk =T _MtrBrk +T _MecBrk , and the expected electric motor torque T _MtrBrk ≤T _Max ; Determining a target allocation ratio that maximizes the sum of the regenerative power of the front motor and the regenerative power of the rear motor based on the desired motor torque T _MtrBrk , the real-time speed n _Front and efficiency η _Front of the front motor of the vehicle, and the real-time speed n _Rear and efficiency η _Rear of the rear motor of the vehicle; Determining a desired braking torque T _Front of the front drive motor and a desired braking torque T _Rear of the rear drive motor based on the target distribution ratio and the desired motor braking torque T _MtrBrk ; Based on the expected braking torque T _Front of the front drive motor and the expected braking torque T _Rear of the rear drive motor, the front drive motor and the rear drive motor are respectively controlled to perform energy recovery, and based on the expected hydraulic braking torque T _MecBrk, the hydraulic brake mechanism of the vehicle is controlled to perform braking. The method according to claim 1 is characterized in that, based on the preset principle of prioritizing the allocation of electric motor braking torque, the energy recovery maximum torque limit T _Max and the required braking torque T _TotBrk , the desired electric motor braking torque T _MtrBrk and the desired hydraulic braking torque T _MecBrk are determined, comprising: When the required braking torque T _TotBrk is greater than the maximum torque limit T _Max , the expected motor braking torque T _MtrBrk =T _Max and the expected hydraulic braking torque T _MecBrk =T _TotBrk -T _Max are determined; When the required braking torque T _TotBrk is less than or equal to the maximum torque limit T _Max , it is determined that the expected motor braking torque T _MtrBrk =T _TotBrk and the expected hydraulic braking torque T _MecBrk =0. The method according to claim 1 or 2, characterized in that, based on the desired motor torque T _MtrBrk , the real-time speed n _Front and efficiency η _Front of the front motor of the vehicle, and the real-time speed n _Rear and efficiency η _Rear of the rear motor of the vehicle, determining a target allocation ratio that maximizes the sum of the regenerated power of the front motor and the regenerated power of the rear motor comprises: Based on the preset value range of the allocation ratio, multiple groups of allocation ratios r _Front and r _Rear are selected from the preset value range according to the preset gradient, wherein r _Front refers to the allocation ratio of the front drive motor, and r _Rear refers to the allocation ratio of the rear drive motor. In the same group of allocation ratios, the sum of r _Front and r _Rear is 100%; Determine the total recovery power under each allocation ratio according to the expected braking torque T _Front , the expected braking torque T _Rear , the real-time speed n _Front and efficiency η _Front of the front drive motor, and the real-time speed n _Rear and efficiency η _Rear of the rear drive motor; From the total recovery power of each group of allocation ratios under the multiple groups of allocation ratios, the allocation ratio corresponding to the maximum total recovery power is selected as the target allocation ratio. The method according to claim 3 is characterized in that the preset value range is 0 to 100%, the preset gradient is 1%, and the values of each group in the multiple groups of allocation ratios (r _Front , r _Rear ) are respectively (0, 100%), (1%, 99%), ..., (100%, 0). The method according to any one of claims 1 to 4, characterized in that the method further comprises: Obtaining the actual braking torque T _ActF of the front drive motor and the actual braking torque T _ActR of the rear drive motor, and obtaining the sum of the actual braking torques T _ActTot =T _ActF +T _ActR ; When the desired electric braking torque T _MtrBrk >T _ActTot , the hydraulic brake mechanism is controlled to compensate for the insufficient electric braking torque T _BrkDif =T _MtrBrk -T _ActTot ; When the desired electric motor braking torque T _MtrBrk ≤T _ActTot and the desired hydraulic braking torque T _MecBrk ≥T _ActTot -T _MtrBrk , the hydraulic brake mechanism is controlled to lower the pressure based on the exceeded electric motor braking torque T _ActTot -T _MtrBrk . The output of the desired motor torque T _MtrBrk . The method according to any one of claims 1 to 5 is characterized in that, before determining the required braking torque T TotBrk corresponding to the current moving depth of the brake pedal when performing a braking operation based on the pre-stored correspondence between the moving depth of the brake _pedal of the vehicle and the braking torque, the method further comprises: Acquire a state data set of the vehicle, the state data set including gear information, vehicle speed, first state information of the front drive motor, second state information of the rear drive motor, third state information of the power battery, and fourth state information of the braking system of the vehicle; Based on the status data set, determine whether the vehicle meets the energy recovery condition, wherein when the gear information indicates that the vehicle is in a forward gear, and the vehicle speed exceeds a preset rate, and the third status information indicates that the power battery has no fault, and the fourth status information indicates that the braking system has no fault, and the first status information indicates that the front drive motor has no fault or the second status information indicates that the rear drive motor has no fault, it is determined that the energy recovery condition is met. The method according to any one of claims 1 to 6 is characterized in that, before determining the required braking torque T TotBrk corresponding to the current moving depth of the brake pedal when performing a braking operation based on the pre-stored correspondence between the moving depth of the brake _pedal of the vehicle and the braking torque, the method further comprises: Obtaining the maximum recovery torque T _MaxF of the front drive motor, the maximum recovery torque T _MaxR of the rear drive motor, and the maximum charging power P _BatMax of the power battery on the vehicle; The maximum torque limit T _Max for motor braking is determined based on the maximum regenerative torque T _MaxF , the maximum regenerative torque T _MaxR and the maximum charging power P _BatMax , wherein T _Max =min(T _MaxF +T _MaxR ,9550P _BatMax /n), and n refers to the equivalent motor speed of the vehicle at the current vehicle speed. A braking energy recovery control device, characterized in that the device comprises: A first determining unit, configured to determine, when the vehicle meets a preset energy recovery condition, a required braking torque T TotBrk corresponding to a current moving depth of the brake pedal when the brake pedal performs a braking operation based on a pre-stored correspondence between the moving depth of the brake pedal of the vehicle and the braking _torque ; a second determining unit, configured to determine a desired electric motor braking torque T _MtrBrk and a desired hydraulic braking torque T _MecBrk based on a preset principle of prioritizing the allocation of electric motor braking torque, a maximum energy recovery torque limit T _Max , and the required braking torque T _TotBrk , and to satisfy T _TotBrk =T _MtrBrk +T _MecBrk , and the desired electric motor braking torque T _MtrBrk ≤T _Max ; a third determining unit, configured to determine a target allocation ratio for maximizing the sum of the regenerative power of the front drive motor and the regenerative power of the rear drive motor based on the desired motor torque T _MtrBrk , the real-time speed n _Front and efficiency η _Front of the front drive motor of the vehicle, and the real-time speed n _Rear and efficiency η _Rear of the rear drive motor of the vehicle; a fourth determining unit, configured to determine an expected braking torque T _Front of the front drive motor and an expected braking torque T _Rear of the rear drive motor based on the target distribution ratio and the expected motor braking torque T _MtrBrk ; The control unit is used to control the front drive motor and the rear drive motor to perform energy recovery based on the expected braking torque T _Front of the front drive motor and the expected braking torque T _Rear of the rear drive motor, and to control the hydraulic brake mechanism of the vehicle to brake based on the expected hydraulic braking torque T _MecBrk . A control system, characterized in that the control system comprises a processing module and a storage module coupled to each other, wherein a computer program is stored in the storage module, and when the computer program is executed by the processing module, the control system executes the method as described in any one of claims 1 to 7. The control system according to claim 9, characterized in that the control system further comprises: A battery management system, a brake system and a brake pedal, wherein the processing module is electrically connected to sensors in the battery management system, the brake system and the brake pedal. The control system according to claim 10, characterized in that the processing module comprises: a powertrain controller, a front drive motor controller, a rear drive motor controller and a gear controller; The powertrain controller is used to receive a signal set from the front drive motor controller, the rear drive motor controller, the battery management system, the brake system, the brake pedal and the gear controller, and integrate the signal set. The signal set is combined to control brake energy recovery. A vehicle, characterized in that the vehicle comprises a vehicle body and a control system as described in any one of claims 9 to 11, wherein the control system is arranged on the vehicle body. A computer-readable storage medium, characterized in that a computer program is stored in the computer-readable storage medium, and when the computer program is run on a computer, the computer is caused to execute the method according to any one of claims 1 to 7. A computer program, characterized in that it comprises program code, and when a computer runs the computer program, the program code executes the method as claimed in any one of claims 1 to 7.