Control method and device for braking energy recovery of rear-axle-driven pure electric vehicle

Abstract

The invention provides a control method and device for braking energy recovery of a rear axle drive pure electric vehicle, and the control method comprises the steps: obtaining a brake pedal opening value and an accelerator pedal opening value of the vehicle in response to the condition that a charge state value and a running speed value of the vehicle meet preset conditions, and determining an energy recovery mode of the vehicle; determining a first energy recovery torque of the drive motor using a regenerative braking table based on the traveling speed value in response to the determination of the slip energy recovery mode; or in response to the braking energy recovery mode, whether the braking strength corresponding to the opening value of the braking pedal belongs to the braking strength interval or not is judged; and if yes, determining a second energy recovery torque of the driving motor based on a control strategy corresponding to the braking strength interval, so that the driving motor performs braking control on the vehicle according to the energy recovery torque. By means of the method, the energy recovery efficiency and the running smoothness of the rear-axle-driven pure electric vehicle are improved, and then the running safety of the vehicle is improved.

Description

Technical Field

[0001] The present application relates to the technical field of braking control for new energy vehicles, and in particular to a control method and device for braking energy recovery for a rear-axle driven pure electric vehicle. Background Art

[0002] When a pure electric vehicle is braking, the use of energy recovery technology can effectively increase the vehicle's mileage. The vehicle's drive motor is converted from an electric motor to a generator, and the wheels drive the drive motor's rotor to rotate to generate and store electrical energy, reducing the overall energy consumption of the pure electric vehicle. At the same time, part of the vehicle's braking force is provided by the drive motor, which can effectively reduce the wear of the brake disc.

[0003] At present, pure electric vehicles with rear-axle drive generally perform energy recovery control through ideal braking force distribution control and optimal braking energy recovery control. The ideal braking force distribution control will provide braking force from the front and rear axles at the same time when the vehicle brakes. When the braking force is small, the vehicle's kinetic energy will still be consumed by the brake disc, reducing the energy recovery efficiency of the pure electric vehicle and increasing the complexity of control. In the optimal braking energy recovery control method, most of the vehicle's braking force is provided by the drive motor of the rear axle, resulting in uncoordinated braking force distribution between the front and rear axles. When the braking force of the rear axle is too large, there will be a problem of the rear axle locking first, reducing the safety of the pure electric vehicle. Summary of the invention

[0004] In view of this, the purpose of the present application is to provide a control method and device for braking energy recovery of a rear-axle driven pure electric vehicle. The energy recovery mode of the vehicle is determined by obtaining a pedal opening value during the driving process of a pure electric vehicle in which a drive motor is located at the rear axle of the vehicle. For each energy recovery mode, the first energy recovery torque of the drive motor is determined so that the drive motor controls the braking of the vehicle according to the energy recovery torque, thereby improving the energy recovery efficiency of the rear-axle driven pure electric vehicle under different working conditions, and improving the problem of poor driving smoothness of the vehicle, thereby improving the safety of vehicle driving.

[0005] The present application provides a control method for braking energy recovery of a rear-axle driven pure electric vehicle, the control method comprising:

[0006] During the driving process of a pure electric vehicle whose driving motor is located at the rear axle of the vehicle, in response to the state of charge value and the driving speed value of the vehicle both satisfying preset conditions, obtaining the brake pedal opening value and the accelerator pedal opening value of the vehicle;

[0007] Determining an energy recovery mode corresponding to the vehicle based on the brake pedal opening value and the accelerator pedal opening value;

[0008] In response to the energy recovery mode being determined as the sliding energy recovery mode, based on the driving speed value, a first energy recovery torque of the drive motor is determined using a preset regenerative braking table, so that the drive motor performs braking control on the vehicle according to the first energy recovery torque;

[0009] or, in response to the energy recovery mode being determined as the braking energy recovery mode, determining whether the braking intensity corresponding to the brake pedal opening value belongs to a preset braking intensity range;

[0010] If the brake pedal opening value belongs to the braking intensity range, the second energy recovery torque of the drive motor is determined based on the control strategy corresponding to the braking intensity range, so that the drive motor controls the braking of the vehicle according to the second energy recovery torque.

[0011] The present application also provides a control device for braking energy recovery of a rear-axle driven pure electric vehicle, the control device comprising:

[0012] A pedal acquisition module, used for acquiring a brake pedal opening value and an accelerator pedal opening value of the vehicle in response to the state of charge value and the driving speed value of the vehicle satisfying preset conditions during the driving process of the pure electric vehicle whose driving motor is located at the rear axle of the vehicle;

[0013] A mode determination module, configured to determine an energy recovery mode corresponding to the vehicle based on the brake pedal opening value and the accelerator pedal opening value;

[0014] a first control module, configured to determine, in response to the energy recovery mode being determined as a sliding energy recovery mode, a first energy recovery torque of the drive motor based on the driving speed value and using a preset regenerative braking table, so that the drive motor performs braking control on the vehicle according to the first energy recovery torque;

[0015] a braking determination module, configured to determine, in response to the energy recovery mode being determined as a braking energy recovery mode, whether the braking intensity corresponding to the brake pedal opening value belongs to a preset braking intensity range;

[0016] The second control module is used to determine the second energy recovery torque of the drive motor based on the control strategy corresponding to the braking intensity interval if the brake pedal opening value belongs to the braking intensity interval, so that the drive motor can brake the vehicle according to the second energy recovery torque.

[0017] An embodiment of the present application also provides an electronic device, including: a processor, a memory and a bus, wherein the memory stores machine-readable instructions executable by the processor, and when the electronic device is running, the processor and the memory communicate through the bus, and when the machine-readable instructions are executed by the processor, the steps of the control method for braking energy recovery of a rear-axle driven pure electric vehicle as described above are performed.

[0018] An embodiment of the present application also provides a computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the steps of the control method for braking energy recovery of a rear-axle driven pure electric vehicle as described above are executed.

[0019] The control method and device for braking energy recovery of a rear-axle driven pure electric vehicle provided in an embodiment of the present application include: during the driving process of a pure electric vehicle whose driving motor is located at the rear axle of the vehicle, in response to the state of charge value and the driving speed value of the vehicle satisfying preset conditions, obtaining the brake pedal opening value and the accelerator pedal opening value of the vehicle; determining the energy recovery mode corresponding to the vehicle based on the brake pedal opening value and the accelerator pedal opening value; in response to the energy recovery mode being determined as a sliding energy recovery mode, determining the first energy recovery torque of the driving motor based on the driving speed value using a preset regenerative braking table, so that the driving motor performs braking control on the vehicle according to the first energy recovery torque; or, in response to the energy recovery mode being determined as a braking energy recovery mode, determining whether the braking intensity corresponding to the brake pedal opening value belongs to a preset braking intensity interval; if the brake pedal opening value belongs to the braking intensity interval, determining the second energy recovery torque of the driving motor based on the control strategy corresponding to the braking intensity interval, so that the driving motor performs braking control on the vehicle according to the second energy recovery torque.

[0020] Compared with the energy recovery control methods of ideal braking force distribution control and optimal braking energy recovery control in the prior art, the energy recovery mode of the vehicle is determined by obtaining the pedal opening value during the driving process of a pure electric vehicle in which the drive motor is located at the rear axle of the vehicle. For each energy recovery mode, the first energy recovery torque of the drive motor is determined so that the drive motor controls the braking of the vehicle according to the energy recovery torque, thereby improving the energy recovery efficiency of rear-axle drive pure electric vehicles under different working conditions, and improving the problem of poor vehicle driving smoothness, thereby improving the safety of vehicle driving.

[0021] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, preferred embodiments are specifically cited below and described in detail with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0023] Figure 1 One of the flow charts of a control method for braking energy recovery of a rear-axle driven pure electric vehicle provided in an embodiment of the present application;

[0024] Figure 2 A schematic diagram of a curve of the front and rear axle braking force distribution relationship provided in an embodiment of the present application;

[0025] Figure 3 A schematic diagram of the relationship between the torque of a driving motor and the vehicle speed provided in an embodiment of the present application;

[0026] Figure 4 A schematic diagram of a membership function corresponding to an energy recovery coefficient provided in an embodiment of the present application;

[0027] Figure 5 A second flowchart of a control method for braking energy recovery of a rear-axle driven pure electric vehicle provided in an embodiment of the present application;

[0028] Figure 6 One of the structural schematic diagrams of a control device for braking energy recovery of a rear-axle driven pure electric vehicle provided in an embodiment of the present application;

[0029] Figure 7 A second structural schematic diagram of a control device for braking energy recovery of a rear-axle driven pure electric vehicle provided in an embodiment of the present application;

[0030] Figure 8 A schematic diagram of the structure of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0031] To make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all of the embodiments. The components of the embodiments of the present application usually described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the application claimed for protection, but merely represents the selected embodiments of the present application. Based on the embodiments of the present application, each other embodiment obtained by those skilled in the art without making creative work belongs to the scope of protection of the present application.

[0032] Research has found that, at present, pure electric vehicles driven by the rear axle generally perform energy recovery control through ideal braking force distribution control and optimal braking energy recovery control. The ideal braking force distribution control will provide braking force from the front and rear axles at the same time when the vehicle brakes. When the braking force is small, the vehicle's kinetic energy will still be consumed by the brake disc, reducing the energy recovery efficiency of the pure electric vehicle and increasing the complexity of control. In the optimal braking energy recovery control method, most of the vehicle's braking force is provided by the drive motor of the rear axle, resulting in uncoordinated braking force distribution between the front and rear axles. When the braking force of the rear axle is too large, there will be a problem of locking the rear axle first, reducing the safety of the pure electric vehicle.

[0033] Based on this, an embodiment of the present application provides a control method for braking energy recovery of a rear-axle driven pure electric vehicle. The energy recovery mode of the vehicle is determined by obtaining a pedal opening value during the driving process of a pure electric vehicle in which the drive motor is located at the rear axle of the vehicle. For each energy recovery mode, the first energy recovery torque of the drive motor is determined so that the drive motor controls the braking of the vehicle according to the energy recovery torque, thereby improving the energy recovery efficiency of the rear-axle driven pure electric vehicle under different working conditions, and improving the problem of poor driving smoothness of the vehicle, thereby improving the safety of vehicle driving.

[0034] See also Figure 1 , Figure 1 This is one of the flow charts of a control method for braking energy recovery of a rear-axle driven pure electric vehicle provided in an embodiment of the present application. Figure 1 As shown in , the control method for braking energy recovery of a rear-axle driven pure electric vehicle provided in an embodiment of the present application includes:

[0035] S101. During driving of a pure electric vehicle whose driving motor is located at a rear axle of the vehicle, in response to the state of charge value and driving speed value of the vehicle satisfying preset conditions, obtaining a brake pedal opening value and an accelerator pedal opening value of the vehicle.

[0036] It should be noted that the vehicle in the embodiments of the present application is generally a pure electric vehicle whose drive motor is located at the rear axle of the vehicle, which is an electric vehicle with a specific layout, that is, a rear-wheel drive (RWD) pure electric drive vehicle, and the power generated by its drive motor is directly transmitted to the rear wheels to make the vehicle move forward or accelerate.

[0037] In this step, the preset conditions include that the state of charge value belongs to a preset state of charge range and the driving speed value is greater than a preset speed value.

[0038] Here, the brake pedal opening value and the accelerator pedal opening value respectively represent the degree of depression of the brake pedal and the accelerator pedal in the vehicle by the driver, that is, the brake pedal opening value and the accelerator pedal opening value may correspond to the braking intensity and the acceleration intensity of the vehicle respectively.

[0039] In one implementation of the present application, during specific implementation, step S101 may include:

[0040] S1011. During the driving process of a pure electric vehicle whose driving motor is located at the rear axle of the vehicle, a state of charge value and a driving speed value of the vehicle are obtained.

[0041] In this step, for the driving process of a pure electric vehicle whose drive motor is located at the rear axle of the vehicle, the battery management system set in the vehicle is used to obtain the charge state value of the vehicle battery, that is, the SOC value (State of Charge), and the VCU controller is used to obtain the real-time driving speed value of the vehicle.

[0042] S1012: Determine whether the state of charge value belongs to a preset state of charge range and whether the driving speed value is greater than a preset speed value.

[0043] In this step, the acquired state of charge value and driving speed value are compared with the preset state of charge range and the preset speed value respectively to determine whether the state of charge value belongs to the preset state of charge range and whether the driving speed value is greater than the preset speed value.

[0044] In the embodiment of the present application, the preset state of charge interval is generally set to [10%, 90%], and the preset speed value is generally set to 15km / h; here, the preset state of charge interval and the preset speed value can also be calibrated according to the vehicle's performance parameters and actual driving conditions.

[0045] S1013. If the state of charge value belongs to a preset state of charge range and the driving speed value is greater than a preset speed value, determine that the state of charge value and the driving speed value of the vehicle both meet preset conditions, and obtain the brake pedal opening value and the accelerator pedal opening value of the vehicle.

[0046] In this step, when the state of charge value belongs to the preset state of charge range and the driving speed value is greater than the preset speed value, it indicates that the vehicle meets the preset conditions at this time, the vehicle's regenerative energy recovery system is turned on, and the vehicle's brake pedal opening value and accelerator pedal opening value are obtained.

[0047] In the embodiment of the present application, when the state of charge value belongs to the preset state of charge range and the driving speed value is greater than the preset speed value, the recovery energy generated by the negative torque of the drive motor will be stored in the battery.

[0048] Among them, when the state of charge value is less than the lower limit of the preset state of charge range, the internal impedance is extremely large due to the low battery power, which is not conducive to the transfer of charge and affects the battery life. At this time, the vehicle's regenerative energy recovery system is turned off; when the state of charge value is greater than the upper limit of the preset state of charge range, the vehicle's regenerative energy recovery system is turned off to prevent overcharging and battery damage; when the driving speed value is less than or equal to the preset speed value, the vehicle speed is too low and the speed of the drive motor is too low, which will cause the voltage generated by the motor to be less than the charging voltage. At this time, the vehicle's regenerative energy recovery system is turned off.

[0049] Furthermore, when the vehicle performs emergency braking, in order to ensure the stability and safety of the vehicle's braking system, the regenerative energy recovery system also needs to be turned off.

[0050] S102: Determine an energy recovery mode corresponding to the vehicle based on the brake pedal opening value and the accelerator pedal opening value.

[0051] In the embodiment of the present application, the energy recovery mode includes a sliding energy recovery mode and a braking energy recovery mode.

[0052] Among them, the sliding energy recovery mode refers to a mode in which the vehicle performs braking energy recovery under a sliding driving condition. In the sliding energy recovery mode, the vehicle's entire vehicle braking force is provided entirely by the braking force of the drive motor; the braking energy recovery mode refers to a mode in which the vehicle performs energy recovery under braking conditions during driving. In the braking energy recovery mode, the vehicle's entire vehicle braking force may include the braking force of the drive motor and the mechanical braking force of the front and rear axles to provide a combined effect.

[0053] In one implementation of the present application, during specific implementation, step S102 may include:

[0054] S1021. When the brake pedal opening value is equal to a first preset value and the accelerator pedal opening value is less than a second preset value, determine that the energy recovery mode corresponding to the vehicle is a sliding energy recovery mode.

[0055] In this step, when the brake pedal opening value is equal to the first preset value and the accelerator pedal opening value is less than the second preset value, it is determined that the energy recovery mode corresponding to the vehicle is the sliding energy recovery mode.

[0056] In the embodiment of the present application, the first preset value is set to 0%, and the second preset value is set to 5%.

[0057] Here, it is set that the vehicle enters the sliding energy recovery mode when the accelerator pedal opening value is less than a second preset value, in order to prevent the driver from accidentally touching the accelerator pedal when the driver releases the accelerator pedal for coasting braking.

[0058] S1022. When the brake pedal opening value is greater than a first preset value and the accelerator pedal opening value is equal to a first preset value, determine that the energy recovery mode corresponding to the vehicle is a braking energy recovery mode.

[0059] In this step, when the brake pedal opening value is greater than the first preset value and the accelerator pedal opening value is equal to the first preset value, it indicates that the vehicle is not actively accelerating but braking at this time, and the energy recovery mode corresponding to the vehicle is determined to be the braking energy recovery mode.

[0060] Furthermore, when the above-mentioned limitations on the brake pedal opening value and the accelerator pedal opening value are not met, the vehicle will shut down the vehicle's regenerative energy recovery system, that is, the vehicle's drive motor will not perform brake energy recovery.

[0061] S103. In response to the energy recovery mode being determined as the sliding energy recovery mode, based on the driving speed value, a first energy recovery torque of the drive motor is determined using a preset regenerative braking table, so that the drive motor performs braking control on the vehicle according to the first energy recovery torque.

[0062] It should be noted that when the driving motor of the vehicle provides braking force, the braking force provided by the driving motor is the regenerative braking force of the energy recovery system, and the braking torque of the driving motor is the energy recovery torque of the energy recovery system.

[0063] In an embodiment of the present application, when the vehicle is in the sliding energy recovery mode, the braking force of the entire vehicle is provided entirely by the braking force of the drive motor, and the magnitude of the braking torque of the motor can be determined according to a preset regenerative braking table, that is, at different vehicle speeds, the magnitude of the energy recovery torque provided by the drive motor is different.

[0064] In this step, when it is determined that the energy recovery mode of the vehicle is the sliding energy recovery mode, the first energy recovery torque of the drive motor corresponding to the driving speed value is determined using a preset regenerative braking table, and the drive motor is controlled to brake the vehicle according to the first energy recovery torque.

[0065] The preset regenerative braking table (Coast Regen Map) may be specifically calibrated according to vehicle performance parameters and vehicle driving experiments.

[0066] Exemplarily, a preset regenerative braking table is shown in the following table.

[0067]

[0068] S104: In response to the energy recovery mode being determined as the braking energy recovery mode, determining whether the braking intensity corresponding to the brake pedal opening value belongs to a preset braking intensity range.

[0069] In an embodiment of the present application, the braking intensity interval includes a first braking intensity interval, a second braking intensity interval and a third braking intensity interval; wherein the first braking intensity interval can be set to (0, 0.12]; the second braking intensity interval can be set to (0.12, 0.24]; the third braking intensity interval can be set to (0.24, 0.7].

[0070] In one embodiment of the present application, in a specific implementation, the step of presetting the braking intensity interval in step S104 may include:

[0071] S104A. Based on the motor force threshold and transmission parameters corresponding to the drive motor, a first braking intensity threshold of the vehicle is determined using a preset first braking intensity calculation formula, and the first braking intensity threshold is determined as the upper limit value of the first braking intensity interval and the lower limit value of the second braking intensity interval, respectively.

[0072] In an embodiment of the present application, the transmission parameters may include transmission ratio, transmission efficiency and wheel radius, and the motor braking force threshold refers to the maximum regenerative braking force that the drive motor can provide when the vehicle's entire braking force is provided entirely by the regenerative braking force of the drive motor.

[0073] In this step, the transmission ratio, the transmission efficiency, the wheel radius and the motor force threshold are input into a preset first braking intensity calculation formula to calculate the first braking intensity threshold.

[0074] Specifically, the expression of the preset first braking intensity calculation formula is as follows.

[0075]

[0076] Wherein, z1 represents the first braking intensity threshold; T tq represents the motor driving force threshold; i o represents the transmission ratio; η represents the transmission efficiency; r represents the wheel radius; G represents the vehicle mass.

[0077] Further, the first braking intensity threshold is determined as an upper limit value of the first braking intensity interval and a lower limit value of the second braking intensity interval respectively.

[0078] S104B. Based on the first rear axle braking force of the vehicle under the motor force threshold, the first front axle braking force corresponding to the first rear axle braking force is determined using a preset front and rear axle braking force distribution relationship to determine the second braking intensity threshold of the vehicle, and the second braking intensity threshold is determined as the upper limit value of the second braking intensity interval and the lower limit value of the third braking intensity interval, respectively.

[0079] In an embodiment of the present application, the preset front and rear axle braking force distribution relationship can be represented by a front and rear axle braking force distribution curve (I curve). The I curve shows the optimal distribution ratio of the front and rear axle braking forces. The I curve represents an ideal front and rear axle braking force distribution curve. If the braking force is distributed according to the I curve, then no matter what adhesion coefficient the vehicle is on the road, the tires of the front and rear axles of the vehicle can always be locked at the same time, so that the car has the most ideal braking effect and can also provide the best handling stability and braking safety.

[0080] For example, see Figure 2 , Figure 2 This is a curve diagram of the front and rear axle braking force distribution relationship provided in an embodiment of the present application. Figure 2 As shown in , the horizontal axis represents the front axle braking force of the vehicle, and the vertical axis represents the rear axle braking force. In the I curve, point A on the graph is the point corresponding to the motor braking force threshold. A horizontal line through point A intersects the I curve at point B, that is, the braking intensity corresponding to point B is the second braking intensity threshold of the vehicle, and the braking intensity corresponding to point C is the emergency braking intensity threshold, that is, the third braking intensity threshold.

[0081] In addition, if Figure 2 The ECE curve shown in , i.e., the M curve, is a standard ECE regulatory curve used to ensure the braking safety of the vehicle, and the I curve must be above the ECE curve.

[0082] In this step, first, the first rear axle braking force under the motor force threshold is determined; then, the first front axle braking force corresponding to the first rear axle braking force is determined in the preset front and rear axle braking force distribution relationship to determine the second braking intensity threshold of the vehicle; finally, the second braking intensity threshold is determined as the upper limit value of the second braking intensity interval and the lower limit value of the third braking intensity interval, respectively.

[0083] In the embodiment of the present application, the second braking intensity threshold of the vehicle is determined based on the first rear axle braking force and the first front axle braking force through the following formula expression.

[0084]

[0085] Wherein, z2 represents the second braking intensity threshold; F r and F f They represent the first rear axle braking force and the first front axle braking force respectively; b represents the distance from the vehicle's mass center to the rear axle; G represents the vehicle's mass; h represents the vehicle's mass. g represents the height of the vehicle's center of mass; L represents the distance between the front and rear axles of the vehicle.

[0086] S104C. Determine the emergency braking intensity threshold corresponding to the vehicle as the third braking intensity threshold, and determine the third braking intensity threshold as the upper limit value of the third braking intensity range.

[0087] In this step, the vehicle will not perform energy recovery during emergency braking. Therefore, the emergency braking intensity threshold corresponding to the vehicle is determined as the third braking intensity threshold, so that the third braking intensity threshold is determined as the upper limit value of the third braking intensity range.

[0088] S105. If the brake pedal opening value belongs to the braking intensity interval, the second energy recovery torque of the drive motor is determined based on the control strategy corresponding to the braking intensity interval, so that the drive motor controls the braking of the vehicle according to the second energy recovery torque.

[0089] In this step, when the brake pedal opening value belongs to the first braking intensity range, the vehicle braking force is determined as the first regenerative braking force of the drive motor, and then the second energy recovery torque corresponding to the first regenerative braking force is determined; when the brake pedal opening value belongs to the second braking intensity range, the second rear axle braking force is determined by using the preset front and rear axle braking force distribution relationship, and the second rear axle braking force is determined as the second regenerative braking force of the drive motor, and then the second energy recovery torque corresponding to the second regenerative braking force is determined; when the brake pedal opening value belongs to the third braking intensity range, the third regenerative braking force of the drive motor is determined by using the preset front and rear axle braking force distribution relationship and the preset recovery compensation formula, and then the second energy recovery torque corresponding to the third regenerative braking force is determined.

[0090] In one implementation of the present application, during specific implementation, step S105 may include:

[0091] S1051. When the brake pedal opening value belongs to the first braking intensity interval, the whole vehicle braking force of the vehicle is determined based on the brake pedal opening value, and the whole vehicle braking force is determined as the first regenerative braking force of the drive motor to determine the second energy recovery torque of the drive motor in the first braking intensity interval.

[0092] In this step, when the brake pedal opening value belongs to the first braking intensity range, it indicates that only a relatively small braking intensity is required during vehicle driving. Determine the overall vehicle braking force of the vehicle, and determine the overall vehicle braking force as the first regenerative braking force of the drive motor.

[0093] Furthermore, based on the first regenerative braking force, the conversion relationship between braking force and torque can be used to determine the second energy recovery torque of the drive motor in the first braking intensity range. At this time, the mechanical friction braking force of the vehicle on the front axle is 0, and the mechanical friction braking force of the vehicle on the rear axle is also 0.

[0094] Exemplarily, when the braking intensity z ≤ 0.12, the drive motor alone provides the braking force, that is, the first regenerative braking force. The distribution of the braking forces on the front and rear axles of the vehicle whose brake pedal opening value belongs to the first braking intensity range corresponds to the OA segment shown in Figure 2 as follows.

[0095] S1052. When the brake pedal opening value belongs to the second braking intensity range, use the preset front and rear axle braking force distribution relationship to determine the second rear axle braking force corresponding to the brake pedal opening value, and determine the second rear axle braking force as the second regenerative braking force of the drive motor to determine the second energy recovery torque of the drive motor in the second braking intensity range.

[0096] In this step, when the brake pedal opening value belongs to the second braking intensity range, the vehicle needs to perform compound braking with the drive motor and the mechanical braking system. At this time, the overall vehicle braking force of the vehicle can include the second regenerative braking force of the drive motor and the second front axle braking force, and the mechanical friction braking force on the rear axle of the vehicle does not need to be connected. That is, determine the second rear axle braking force as the second regenerative braking force of the drive motor, and then use the conversion relationship between braking force and torque to determine the second energy recovery torque of the drive motor in the second braking intensity range.

[0097] Exemplarily, when the braking intensity 0.12 < z ≤ 0.24, the vehicle needs to perform compound braking with the drive motor and the mechanical braking system. The braking forces on the front and rear wheels are distributed as shown in the AB segment in Figure 2 as follows. That is, use the AB segment shown in Figure 2 to determine the second rear axle braking force (second regenerative braking force) of the vehicle whose brake pedal opening value belongs to the second braking intensity range, and then the second energy recovery torque of the drive motor in the second braking intensity range can be determined.

[0098] Here, when the second regenerative braking force provided by the drive motor is less than the required second rear axle braking force, the mechanical friction braking force can be provided by the mechanical braking system on the rear axle for braking compensation.

[0099] In an embodiment of the present application, the second energy recovery torque of the driving motor in the second braking intensity range is affected by the power and speed of the driving motor, and the maximum threshold value of the second energy recovery torque of the driving motor in the second braking intensity range can be determined by the following formula expression.

[0100]

[0101] Among them, T re represents the maximum threshold value of the second energy recovery torque, n b is the rated speed; T re,max is the maximum regenerative torque of the motor; P mot,max is the rated power of the motor; n is the speed.

[0102] For details, please refer to Figure 3 , Figure 3 This is a schematic diagram of the relationship between the torque of a driving motor and the vehicle speed provided in an embodiment of the present application. Figure 3 As shown in , the horizontal axis is the vehicle's driving speed value, and the vertical axis is the braking torque output by the vehicle. When the motor speed is higher than the rated speed, the regenerative braking torque that the motor can provide gradually decreases; when the motor cannot provide the braking torque required by the vehicle, braking compensation can be performed through the mechanical friction braking force provided by the vehicle's mechanical braking system.

[0103] S1053. When the brake pedal opening value belongs to the third braking intensity range, the third rear axle braking force corresponding to the brake pedal opening value is determined by using the preset front and rear axle braking force distribution relationship, and based on the third rear axle braking force, the third regenerative braking force of the drive motor is determined by using the preset recovery compensation formula to determine the second energy recovery torque of the drive motor in the third braking intensity range.

[0104] In this step, when the brake pedal opening value belongs to the third braking intensity range, the vehicle also needs to drive the motor and mechanical braking system to perform compound braking. At this time, the mechanical friction braking force of the vehicle at the rear axle provides compensation for the rear axle braking. Specifically, based on the third rear axle braking force, the third regenerative braking force of the drive motor is determined using a preset recovery compensation formula, and then the conversion relationship between braking force and torque is used to determine the third energy recovery torque of the drive motor in the third braking intensity range.

[0105] In an embodiment of the present application, the expression of the preset recovery compensation formula is as follows.

[0106] F re =F r ×K×R.

[0107] Among them, F re Indicates the third regenerative braking force of the drive motor; Fr represents the braking force of the third rear axle; K represents the energy recovery coefficient; R represents the correction coefficient.

[0108] In one implementation of the present application, during specific implementation, step S1053 may include:

[0109] S10531. Determine the degree labels corresponding to the state of charge value, the driving speed value, and the brake pedal opening value respectively, and determine the energy recovery coefficient of the drive motor based on the degree labels using a preset energy recovery coefficient table.

[0110] In the embodiment of the present application, since the braking force provided by the drive motor is different under different driving conditions, the regenerative braking force of the motor is mainly affected by the state of charge value, driving speed value and braking intensity. Therefore, the above-mentioned degree of influence is determined by the energy recovery coefficient.

[0111] Here, the degree labels corresponding to the state of charge values ​​may include L (low), M (medium), and H (high), and the domain corresponding to the state of charge values ​​is defined as {0.1, 0.9}; the degree labels corresponding to the driving speed values ​​may include L (low), M (medium), and H (high), and the domain corresponding to the driving speed values ​​is defined as {15, 120}; the degree labels corresponding to the braking intensity may include L (low), M (medium), and H (high), and the domain corresponding to the braking intensity is defined as {0.12, 0.7}.

[0112] Furthermore, the energy recovery coefficient of the drive motor may correspond to values ​​under different membership functions, and the membership labels of the energy recovery coefficient may include VL (low), L (low), M (medium), H (high), and VH (very high), and the domain corresponding to the energy recovery coefficient is defined as {0, 1}.

[0113] For example, see Figure 4 , Figure 4 A schematic diagram of a membership function corresponding to an energy recovery coefficient provided in an embodiment of the present application. Figure 4 As shown in , the membership relationship between the energy recovery coefficient and the state of charge value and the driving speed value can be determined, and the membership relationship between the energy recovery coefficient and the state of charge value and the braking intensity can be determined.

[0114] Specifically, the preset energy recovery coefficient table is shown in the following table.

[0115]

[0116] S10532. Obtain the vehicle mass and the slope value of the road on which the vehicle is traveling, and based on the vehicle mass and the slope value, determine the correction coefficient of the drive motor using a preset correction coefficient table.

[0117] In the embodiment of the present application, the preset correction coefficient table is shown in the following table.

[0118]

[0119]

[0120] S10533. Based on the third rear axle braking force, the energy recovery coefficient and the correction coefficient, determine the third regenerative braking force of the drive motor using a preset recovery compensation formula.

[0121] In this step, the third rear axle braking force, the energy recovery coefficient and the correction coefficient are input into a preset recovery compensation formula, and the third regenerative braking force of the drive motor is determined by calculation.

[0122] S1054: Control the drive motor to perform braking control on the rear axle of the vehicle according to the second energy recovery torque.

[0123] In an embodiment of the present application, when the braking intensity is medium, that is, when the brake pedal opening value belongs to the third braking intensity interval, an energy recovery coefficient and a correction coefficient are introduced, and the size of the third regenerative braking force of the drive motor is allocated by adaptive and fuzzy control strategies. The purpose is to increase the proportion of the third regenerative braking force of the drive motor as much as possible while meeting the vehicle's handling stability and braking safety, and then control the drive motor to brake the rear axle of the vehicle according to the second energy recovery torque corresponding to the third regenerative braking force.

[0124] Optional, see Figure 5 , Figure 5 This is a second flow chart of a control method for braking energy recovery of a rear-axle driven pure electric vehicle provided in an embodiment of the present application. Figure 5 As shown in , in addition to the control method for braking energy recovery of a rear-axle driven pure electric vehicle described in steps S101 to S105, the embodiment of the present application also includes step S106. Specifically, step S106 is used to illustrate the control method when the brake pedal opening value does not belong to the braking intensity range, so as to improve the efficiency of energy recovery.

[0125] S106. If the brake pedal opening value does not belong to the braking intensity range, a first preset value is determined as the second energy recovery torque of the drive motor, and based on the brake pedal opening value, the vehicle is mechanically braked according to a preset front and rear axle braking force distribution relationship.

[0126] In the implementation of this application, the first preset value is set to 0, that is, the second energy recovery torque of the drive motor is 0. In order to ensure braking safety and handling stability, the vehicle's braking energy recovery system is turned off, and the braking force of the entire vehicle is provided by the mechanical friction of the front and rear axles.

[0127] In this step, the front and rear axle braking forces corresponding to the brake pedal opening value are determined in the preset front and rear axle braking force distribution relationship, and the vehicle is mechanically braked according to the front and rear axle braking forces using the vehicle's mechanical braking system.

[0128] The control method for braking energy recovery of a rear-axle driven pure electric vehicle provided in an embodiment of the present application determines the energy recovery mode of the vehicle by obtaining a pedal opening value during the driving process of the pure electric vehicle in which the drive motor is located at the rear axle of the vehicle, and determines the first energy recovery torque of the drive motor for each energy recovery mode, so that the drive motor controls the braking of the vehicle according to the energy recovery torque, thereby improving the energy recovery efficiency of the rear-axle driven pure electric vehicle under different operating conditions, and improving the problem of poor driving smoothness of the vehicle, thereby improving the safety of vehicle driving.

[0129] See also Figure 6 , Figure 7 , Figure 6 This is one of the structural schematic diagrams of a control device for braking energy recovery of a rear-axle driven pure electric vehicle provided in an embodiment of the present application. Figure 7 The second structural schematic diagram of a control device for braking energy recovery of a rear-axle driven pure electric vehicle provided in an embodiment of the present application.

[0130] like Figure 6 As shown in , the control device 600 includes:

[0131] The pedal acquisition module 610 is used to acquire the brake pedal opening value and the accelerator pedal opening value of the vehicle in response to the state of charge value and the driving speed value of the vehicle satisfying preset conditions during the driving process of the pure electric vehicle whose driving motor is located at the rear axle of the vehicle;

[0132] A mode determination module 620, configured to determine an energy recovery mode corresponding to the vehicle based on the brake pedal opening value and the accelerator pedal opening value;

[0133] a first control module 630, configured to determine, in response to the energy recovery mode being determined as the sliding energy recovery mode, based on the driving speed value, a first energy recovery torque of the drive motor using a preset regenerative braking table, so that the drive motor performs braking control on the vehicle according to the first energy recovery torque;

[0134] A braking determination module 640, configured to determine, in response to the energy recovery mode being determined as a braking energy recovery mode, whether the braking intensity corresponding to the brake pedal opening value belongs to a preset braking intensity range;

[0135] The second control module 650 is used to determine the second energy recovery torque of the drive motor based on the control strategy corresponding to the braking intensity interval if the brake pedal opening value belongs to the braking intensity interval, so that the drive motor can control the braking of the vehicle according to the second energy recovery torque.

[0136] Furthermore, when the pedal acquisition module 610 is used to obtain the brake pedal opening value and the accelerator pedal opening value of the vehicle in response to the state of charge value and the driving speed value of the vehicle satisfying preset conditions during the driving process of the pure electric vehicle whose driving motor is located at the rear axle of the vehicle, the pedal acquisition module 610 is used to:

[0137] During the driving process of a pure electric vehicle whose driving motor is located at the rear axle of the vehicle, obtaining a state of charge value and a driving speed value of the vehicle;

[0138] Determining whether the state of charge value belongs to a preset state of charge range and whether the driving speed value is greater than a preset speed value;

[0139] If the state of charge value belongs to a preset state of charge range and the driving speed value is greater than a preset speed value, it is determined that the state of charge value and the driving speed value of the vehicle both meet preset conditions, and the brake pedal opening value and the accelerator pedal opening value of the vehicle are obtained.

[0140] Further, when the mode determination module 620 is used to determine the energy recovery mode corresponding to the vehicle based on the brake pedal opening value and the accelerator pedal opening value, the mode determination module 620 is used to:

[0141] When the brake pedal opening value is equal to a first preset value and the accelerator pedal opening value is less than a second preset value, determining that the energy recovery mode corresponding to the vehicle is a sliding energy recovery mode;

[0142] When the brake pedal opening value is greater than a first preset value and the accelerator pedal opening value is equal to a first preset value, it is determined that the energy recovery mode corresponding to the vehicle is a braking energy recovery mode.

[0143] Furthermore, when the braking determination module 640 is used to pre-set the braking intensity interval, the braking determination module 640 is used to:

[0144] Based on the motor force threshold and transmission parameters corresponding to the drive motor, a first braking intensity threshold of the vehicle is determined using a preset first braking intensity calculation formula, and the first braking intensity threshold is determined as an upper limit value of a first braking intensity interval and a lower limit value of a second braking intensity interval respectively;

[0145] Based on the first rear axle braking force of the vehicle at the motor braking force threshold, a first front axle braking force corresponding to the first rear axle braking force is determined using a preset front and rear axle braking force distribution relationship to determine a second braking intensity threshold of the vehicle, and the second braking intensity threshold is determined as an upper limit value of a second braking intensity interval and a lower limit value of a third braking intensity interval, respectively;

[0146] The emergency braking intensity threshold corresponding to the vehicle is determined as a third braking intensity threshold, and the third braking intensity threshold is determined as an upper limit value of a third braking intensity range.

[0147] Further, when the second control module 650 is used to determine the second energy recovery torque of the drive motor based on the control strategy corresponding to the braking intensity interval if the brake pedal opening value belongs to the braking intensity interval, so that the drive motor performs braking control on the vehicle according to the second energy recovery torque, the second control module 650 is used to:

[0148] When the brake pedal opening value belongs to a first braking intensity interval, based on the brake pedal opening value, determining the whole vehicle braking force of the vehicle, and determining the whole vehicle braking force as the first regenerative braking force of the drive motor, so as to determine the second energy recovery torque of the drive motor in the first braking intensity interval;

[0149] When the brake pedal opening value belongs to the second braking intensity interval, a second rear axle braking force corresponding to the brake pedal opening value is determined by using a preset front and rear axle braking force distribution relationship, and the second rear axle braking force is determined as the second regenerative braking force of the drive motor to determine a second energy recovery torque of the drive motor in the second braking intensity interval;

[0150] When the brake pedal opening value belongs to a third braking intensity interval, a third rear axle braking force corresponding to the brake pedal opening value is determined using a preset front and rear axle braking force distribution relationship, and based on the third rear axle braking force, a third regenerative braking force of the drive motor is determined using a preset recovery compensation formula to determine a second energy recovery torque of the drive motor in the third braking intensity interval;

[0151] The drive motor is controlled to perform braking control on a rear axle of the vehicle according to the second energy recovery torque.

[0152] Further, when the second control module 650 is used to determine the third regenerative braking force of the drive motor based on the third rear axle braking force using a preset recovery compensation formula, the second control module 650 is used to:

[0153] Determining the degree labels corresponding to the state of charge value, the driving speed value, and the brake pedal opening value, respectively, and determining the energy recovery coefficient of the drive motor based on the degree labels using a preset energy recovery coefficient table;

[0154] Obtaining the vehicle mass and the slope value of the road on which the vehicle is traveling, and determining the correction coefficient of the drive motor based on the vehicle mass and the slope value using a preset correction coefficient table;

[0155] Based on the third rear axle braking force, the energy recovery coefficient and the correction coefficient, a third regenerative braking force of the drive motor is determined using a preset recovery compensation formula.

[0156] Further, such as Figure 7 As shown in , the control device 600 further includes a third control module 660, and the third control module 660 is used to:

[0157] If the brake pedal opening value does not belong to the braking intensity range, the first preset value is determined as the second energy recovery torque of the drive motor, and based on the brake pedal opening value, the vehicle is mechanically braked according to a preset front and rear axle braking force distribution relationship.

[0158] The control device for braking energy recovery of a rear-axle driven pure electric vehicle provided in the embodiment of the present application determines the energy recovery mode of the vehicle by obtaining a pedal opening value during the driving process of the pure electric vehicle in which the drive motor is located at the rear axle of the vehicle, and determines the first energy recovery torque of the drive motor for each energy recovery mode so that the drive motor controls the braking of the vehicle according to the energy recovery torque, thereby improving the energy recovery efficiency of the rear-axle driven pure electric vehicle under different operating conditions, and improving the problem of poor driving smoothness of the vehicle, thereby improving the safety of vehicle driving.

[0159] See also Figure 8 , Figure 8 This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present application. Figure 8 As shown in , the electronic device 800 includes a processor 810 , a memory 820 and a bus 830 .

[0160] The memory 820 stores machine-readable instructions executable by the processor 810. When the electronic device 800 is running, the processor 810 communicates with the memory 820 via the bus 830. When the machine-readable instructions are executed by the processor 810, the above-mentioned Figure 1 as well as Figure 5 The steps of the control method for braking energy recovery of a rear-axle driven pure electric vehicle in the method embodiment shown in the embodiment and the specific implementation thereof can be referred to the method embodiment, which will not be described in detail here.

[0161] The present application also provides a computer-readable storage medium on which a computer program is stored. When the computer program is executed by a processor, the computer program can execute the above-mentioned Figure 1 as well as Figure 5 The steps of the control method for braking energy recovery of a rear-axle driven pure electric vehicle in the method embodiment shown in the embodiment and the specific implementation thereof can be referred to the method embodiment, which will not be described in detail here.

[0162] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0163] In the several embodiments provided in the present application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. The device embodiments described above are merely schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some communication interfaces, and the indirect coupling or communication connection of devices or units can be electrical, mechanical or other forms.

[0164] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0165] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0166] If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a non-volatile computer-readable storage medium that is executable by a processor. Based on this understanding, the technical solution of the present application can essentially be embodied in the form of a software product, or in other words, the part that contributes to the prior art or the part of the technical solution. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0167] Finally, it should be noted that the above-described embodiments are only specific implementation methods of the present application, which are used to illustrate the technical solutions of the present application, rather than to limit them. The protection scope of the present application is not limited thereto. Although the present application is described in detail with reference to the above-mentioned embodiments, ordinary technicians in the field should understand that any technician familiar with the technical field can still modify the technical solutions recorded in the above-mentioned embodiments within the technical scope disclosed in the present application, or can easily think of changes, or make equivalent replacements for some of the technical features therein; and these modifications, changes or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application, and should be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. A control method for braking energy recovery of a rear-axle driven pure electric vehicle, characterized in that: The control method comprises: During the driving process of a pure electric vehicle whose driving motor is located at the rear axle of the vehicle, in response to the state of charge value and the driving speed value of the vehicle both satisfying preset conditions, obtaining the brake pedal opening value and the accelerator pedal opening value of the vehicle; Determining an energy recovery mode corresponding to the vehicle based on the brake pedal opening value and the accelerator pedal opening value; In response to the energy recovery mode being determined as the sliding energy recovery mode, based on the driving speed value, a first energy recovery torque of the drive motor is determined using a preset regenerative braking table, so that the drive motor performs braking control on the vehicle according to the first energy recovery torque; or, in response to the energy recovery mode being determined as the braking energy recovery mode, determining whether the braking intensity corresponding to the brake pedal opening value belongs to a preset braking intensity range; If the brake pedal opening value belongs to the braking intensity range, the second energy recovery torque of the drive motor is determined based on the control strategy corresponding to the braking intensity range, so that the drive motor controls the braking of the vehicle according to the second energy recovery torque.

2. The method according to claim 1, characterized in that During the driving process of the pure electric vehicle with the driving motor located at the rear axle of the vehicle, in response to the state of charge value and the driving speed value of the vehicle satisfying the preset conditions, obtaining the brake pedal opening value and the accelerator pedal opening value of the vehicle, including: During the driving process of a pure electric vehicle whose driving motor is located at the rear axle of the vehicle, obtaining a state of charge value and a driving speed value of the vehicle; Determining whether the state of charge value belongs to a preset state of charge range and whether the driving speed value is greater than a preset speed value; If the state of charge value belongs to a preset state of charge range and the driving speed value is greater than a preset speed value, it is determined that the state of charge value and the driving speed value of the vehicle both meet preset conditions, and the brake pedal opening value and the accelerator pedal opening value of the vehicle are obtained.

3. The method according to claim 1, characterized in that The determining, based on the brake pedal opening value and the accelerator pedal opening value, the energy recovery mode corresponding to the vehicle includes: When the brake pedal opening value is equal to a first preset value and the accelerator pedal opening value is less than a second preset value, determining that the energy recovery mode corresponding to the vehicle is a sliding energy recovery mode; When the brake pedal opening value is greater than a first preset value and the accelerator pedal opening value is equal to a first preset value, it is determined that the energy recovery mode corresponding to the vehicle is a braking energy recovery mode.

4. The method according to claim 1, characterized in that: The braking intensity interval is pre-set by the following steps: Based on the motor force threshold and transmission parameters corresponding to the drive motor, a first braking intensity threshold of the vehicle is determined using a preset first braking intensity calculation formula, and the first braking intensity threshold is determined as an upper limit value of a first braking intensity interval and a lower limit value of a second braking intensity interval respectively; Based on the first rear axle braking force of the vehicle at the motor braking force threshold, a first front axle braking force corresponding to the first rear axle braking force is determined using a preset front and rear axle braking force distribution relationship to determine a second braking intensity threshold of the vehicle, and the second braking intensity threshold is determined as an upper limit value of a second braking intensity interval and a lower limit value of a third braking intensity interval, respectively; The emergency braking intensity threshold corresponding to the vehicle is determined as the third braking intensity threshold, and the third braking intensity threshold is determined as the upper limit value of the third braking intensity range.

5. The method according to claim 1, characterized in that If the brake pedal opening value belongs to the braking intensity interval, determining the second energy recovery torque of the drive motor based on the control strategy corresponding to the braking intensity interval so that the drive motor performs braking control on the vehicle according to the second energy recovery torque includes: When the brake pedal opening value belongs to a first braking intensity interval, based on the brake pedal opening value, determining the whole vehicle braking force of the vehicle, and determining the whole vehicle braking force as the first regenerative braking force of the drive motor, so as to determine the second energy recovery torque of the drive motor in the first braking intensity interval; When the brake pedal opening value belongs to the second braking intensity interval, a second rear axle braking force corresponding to the brake pedal opening value is determined by using a preset front and rear axle braking force distribution relationship, and the second rear axle braking force is determined as the second regenerative braking force of the drive motor to determine a second energy recovery torque of the drive motor in the second braking intensity interval; When the brake pedal opening value belongs to a third braking intensity interval, a third rear axle braking force corresponding to the brake pedal opening value is determined using a preset front and rear axle braking force distribution relationship, and based on the third rear axle braking force, a third regenerative braking force of the drive motor is determined using a preset recovery compensation formula to determine a second energy recovery torque of the drive motor in the third braking intensity interval; The drive motor is controlled to perform braking control on a rear axle of the vehicle according to the second energy recovery torque.

6. The method according to claim 5, characterized in that The method of determining the third regenerative braking force of the drive motor based on the third rear axle braking force by using a preset recovery compensation formula includes: Determining the degree labels corresponding to the state of charge value, the driving speed value, and the brake pedal opening value, respectively, and determining the energy recovery coefficient of the drive motor based on the degree labels using a preset energy recovery coefficient table; Obtaining the vehicle mass and the slope value of the road on which the vehicle is traveling, and determining the correction coefficient of the drive motor based on the vehicle mass and the slope value using a preset correction coefficient table; Based on the third rear axle braking force, the energy recovery coefficient and the correction coefficient, a third regenerative braking force of the drive motor is determined using a preset recovery compensation formula.

7. The method according to claim 1, characterized in that The control method further comprises: If the brake pedal opening value does not belong to the braking intensity range, the first preset value is determined as the second energy recovery torque of the drive motor, and based on the brake pedal opening value, the vehicle is mechanically braked according to a preset front and rear axle braking force distribution relationship.

8. A control device for braking energy recovery of a rear-axle driven pure electric vehicle, characterized in that: The control device comprises: A pedal acquisition module, used for acquiring a brake pedal opening value and an accelerator pedal opening value of the vehicle in response to the state of charge value and the driving speed value of the vehicle satisfying preset conditions during the driving process of the pure electric vehicle whose driving motor is located at the rear axle of the vehicle; A mode determination module, configured to determine an energy recovery mode corresponding to the vehicle based on the brake pedal opening value and the accelerator pedal opening value; a first control module, configured to determine, in response to the energy recovery mode being determined as a sliding energy recovery mode, a first energy recovery torque of the drive motor based on the driving speed value and using a preset regenerative braking table, so that the drive motor performs braking control on the vehicle according to the first energy recovery torque; a braking determination module, configured to determine, in response to the energy recovery mode being determined as a braking energy recovery mode, whether the braking intensity corresponding to the brake pedal opening value belongs to a preset braking intensity range; The second control module is used to determine the second energy recovery torque of the drive motor based on the control strategy corresponding to the braking intensity interval if the brake pedal opening value belongs to the braking intensity interval, so that the drive motor can brake the vehicle according to the second energy recovery torque.

9. An electronic device, characterized in that: include: A processor, a memory and a bus, wherein the memory stores machine-readable instructions executable by the processor, and when the electronic device is running, the processor and the memory communicate through the bus, and the machine-readable instructions are executed by the processor when running to execute the steps of the control method for braking energy recovery of a rear-axle driven pure electric vehicle as described in any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the control method for braking energy recovery of a rear-axle driven pure electric vehicle as claimed in any one of claims 1 to 7 are executed.

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