Vehicle braking energy recovery control method and system

Abstract

The invention provides a vehicle braking energy recovery control method and system. The method comprises the steps that the maximum recovery torque value corresponding to a wheel end system in a hybrid vehicle is calculated in real time; the sliding energy recovery torque and the driving motor power generation torque correspondingly generated in the operation process of the hybrid vehicle are calculated in real time, and the corresponding braking energy recovery available electric power is calculated in real time according to the maximum recovery torque value, the sliding energy recovery torque and the driving motor power generation torque; calculating an electric braking recovery maximum capacity limit and a generator maximum power generation capacity limit corresponding to the hybrid vehicle in real time based on a preset rule; and according to the electric braking recovery maximum capacity limit and the generator maximum power generation capacity limit, braking energy recovery request torque and generator request torque calculated corresponding to the hybrid vehicle are limited so as to complete corresponding braking energy recovery control. The problem of over-charging or over-discharging of the brake recovery battery pack can be solved, the brake recovery efficiency can be improved, the energy consumption of the whole vehicle is reduced, the endurance mileage of the whole vehicle is increased, and the user experience is correspondingly improved.

Description

Technical Field

[0001] The present invention relates to the field of automobile technology, and in particular to a vehicle braking energy recovery control method and system. Background Art

[0002] With the advancement of science and technology and the rapid development of productivity, cars have become popular in people's daily lives and have become one of the indispensable means of transportation for people's daily travel, greatly facilitating people's lives.

[0003] Among them, existing pure electric models and hybrid models are equipped with brake energy recovery function. Specifically, the existing brake energy recovery is to feed back electricity through electric braking when the driver steps on the brake pedal to achieve energy saving. When the electric braking power does not meet the braking needs of the whole vehicle, mechanical braking is used to ensure the braking effect of the whole vehicle. In pure electric vehicles, only the battery pack and the drive motor work in the braking recovery scheme. When the driver steps on the brake, the energy distribution in the braking recovery process can be completed by limiting the recovery power of the drive motor according to the available power of the battery pack. However, in hybrid vehicles, the actual charging and discharging power of the battery pack is determined by the drive motor and the generator. The drive motor is not only related to the torque required by the driver, but also includes the working condition that the engine generates electricity to the battery pack through the drive motor. Therefore, coordinating the energy distribution of the engine, drive motor, generator, and electric braking torque becomes a key issue in hybrid energy recovery. Because the generator, engine, and drive motor of hybrid vehicles work together, the engine can charge the battery through the generator, and can also charge the battery pack through the drive motor. Under these two working conditions, the available power of electric braking and the battery pack power are not equal. If the situation where the battery pack power and the available power of electric braking continue to be equal will cause problems such as battery overcharging or over-discharging. Summary of the invention

[0004] Based on this, the purpose of the present invention is to provide a vehicle braking energy recovery control method and system to solve the problem that if the existing hybrid vehicle model completes braking energy recovery in a manner that the available electric braking power is equal to the available battery pack power, it may cause the battery pack to be overcharged or over-discharged. Because the generator, engine, and drive motor of the hybrid vehicle model work together, the engine can charge the battery through the generator, and can also charge the battery pack through the drive motor. Under these two working conditions, the available electric braking power and the battery pack power are not equal. If the battery pack power continues to be equal to the available electric braking power, it will cause the battery to be overcharged or over-discharged.

[0005] The first aspect of the embodiment of the present invention proposes:

[0006] A vehicle braking energy recovery control method, wherein the method comprises:

[0007] When it is detected in real time that the hybrid vehicle is in a running state, a maximum torque value of recovery corresponding to a wheel-end system inside the hybrid vehicle is calculated in real time;

[0008] Calculate in real time the coasting energy recovery torque and the driving motor power generation torque generated during the operation of the hybrid vehicle, and calculate in real time the corresponding braking energy recovery available electric power according to the maximum recovery torque value, the coasting energy recovery torque and the driving motor power generation torque;

[0009] Calculate in real time based on preset rules the maximum capacity limit of electric braking recovery and the maximum power generation capacity limit of the generator corresponding to the hybrid vehicle;

[0010] According to the electric brake recovery maximum capacity limit and the generator maximum power generation capacity limit, the brake energy recovery request torque and the generator request torque calculated corresponding to the hybrid vehicle are limited to complete the corresponding brake energy recovery control.

[0011] The beneficial effects of the present invention are:

[0012] Key point 1: Energy management of brake energy recovery, based on the available power of the battery pack, the wheel-end coasting torque, and the drive motor power generation torque (engine part), calculates the maximum wheel-end torque allowed for electric braking recovery in electric braking mode. The request to execute electric braking must be within this limit;

[0013] Key point 2: The braking recovery strategy adopts the wheel-end priority principle to improve the drivability of the entire vehicle. When the available power of the battery pack is low, the wheel-end recovery torque is prioritized to reduce the power generation of the generator. As a result, as the system opening increases under the braking condition, the braking energy recovery increases and the generator power generation decreases. When the braking energy recovery power is equal to the available power of the battery pack, the generator power generation is zero.

[0014] Furthermore, the method further comprises:

[0015] A throttle, vehicle speed, and coasting energy recovery torque mapping table is designed, and the current driving coasting energy recovery torque is calculated according to the throttle and vehicle speed mapping table.

[0016] The method further comprises:

[0017] When it is detected in real time that the hybrid vehicle is in a driving state, the actual wheel end torque corresponding to the hybrid vehicle is calculated in real time. The actual wheel end torque is equal to the actual output torque of the clutch multiplied by the gear ratio plus the drive motor torque multiplied by the motor gear ratio.

[0018] Furthermore, during the driving of the hybrid vehicle, a corresponding braking energy recovery value is displayed in real time on the instrument panel of the hybrid vehicle, and the braking energy recovery value changes dynamically.

[0019] The second aspect of the embodiment of the present invention proposes:

[0020] A vehicle braking energy recovery control system, wherein the system comprises:

[0021] A detection module, configured to calculate in real time a maximum recovery torque value corresponding to a wheel-end system inside the hybrid vehicle when detecting in real time that the hybrid vehicle is in a running state;

[0022] A first processing module is used to calculate in real time the coasting energy recovery torque and the driving motor power generation torque generated during the operation of the hybrid vehicle, and calculate in real time the corresponding braking energy recovery available electric power according to the maximum recovery torque value, the coasting energy recovery torque and the driving motor power generation torque;

[0023] A second processing module is used to calculate in real time based on preset rules the maximum capacity limit of electric braking recovery and the maximum power generation capacity limit of the generator corresponding to the hybrid vehicle;

[0024] The third processing module is used to calibrate the clutch, gearbox and engine inside the vehicle according to the judgment result, and test the driving performance of the vehicle according to the driving wheel end of the engine in real time.

[0025] Furthermore, the method further comprises:

[0026] A throttle and vehicle speed mapping table is retrieved, and the coasting energy recovery torque is calculated accordingly according to the throttle and vehicle speed mapping table.

[0027] Furthermore, the method further comprises:

[0028] When it is detected in real time that the hybrid vehicle is in a driving state, the actual wheel end torque corresponding to the hybrid vehicle is calculated in real time. The actual wheel end torque is equal to the actual output torque of the clutch multiplied by the gear ratio plus the drive motor torque multiplied by the motor gear ratio.

[0029] Further, according to the electric brake recovery maximum capacity limit and the generator maximum power generation capacity limit, the brake energy recovery request torque and the generator request torque calculated corresponding to the hybrid vehicle are limited to complete the corresponding brake energy recovery control.

[0030] The third aspect of the embodiment of the present invention proposes:

[0031] A computer comprises a memory, a processor and a computer program stored in the memory and executable on the processor, wherein the vehicle braking energy recovery control method as described above is implemented when the processor executes the computer program.

[0032] The fourth aspect of the embodiments of the present invention proposes:

[0033] A readable storage medium stores a computer program, wherein when the program is executed by a processor, the vehicle braking energy recovery control method as described above is implemented.

[0034] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 A flow chart of a vehicle braking energy recovery control method provided by a first embodiment of the present invention;

[0036] Figure 2 A logic diagram of a vehicle braking energy recovery control method provided by a second embodiment of the present invention;

[0037] Figure 3 A schematic diagram of an implementation of a vehicle braking energy recovery control method provided in a second embodiment of the present invention;

[0038] Figure 4 This is a structural block diagram of a vehicle braking energy recovery control system provided in the third embodiment of the present invention.

[0039] The following specific implementation manner will further illustrate the present invention in conjunction with the above-mentioned drawings. DETAILED DESCRIPTION

[0040] In order to facilitate the understanding of the present invention, the present invention will be described more fully below with reference to the relevant drawings. Several embodiments of the present invention are given in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present invention more thorough and comprehensive.

[0041] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only.

[0042] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0043] See also Figure 1 , shown is a vehicle braking energy recovery control method provided by the first embodiment of the present invention. The vehicle braking energy recovery control method provided by this embodiment can accurately and effectively calculate the braking energy recovery value, ensure that the battery pack is not overcharged or over-discharged, reduce the energy consumption of the whole vehicle, and correspondingly improve the cruising range of the whole vehicle while improving the user experience.

[0044] Specifically, this embodiment provides:

[0045] A vehicle braking energy recovery control method comprises the following steps:

[0046] Step S10, when it is detected in real time that the hybrid vehicle is in a running state, a maximum regenerative torque value corresponding to a wheel-end system inside the hybrid vehicle is calculated in real time;

[0047] Step S20, calculating in real time the coasting energy recovery torque and the driving motor power generation torque generated during the operation of the hybrid vehicle, and calculating in real time the corresponding braking energy recovery available electric power according to the maximum recovery torque value, the coasting energy recovery torque and the driving motor power generation torque;

[0048] Step S30, calculating in real time based on preset rules the maximum capacity limit of electric braking recovery and the maximum power generation capacity limit of the generator corresponding to the hybrid vehicle;

[0049] Step S40 , limiting the braking energy recovery request torque and the generator request torque calculated corresponding to the hybrid vehicle according to the electric braking recovery maximum capacity limit and the generator maximum power generation capacity limit to complete the corresponding braking energy recovery control.

[0050] Second embodiment

[0051] See also Figures 2 to 3 , the overall idea provided by this embodiment is:

[0052] 1. Calculate the maximum torque value recovered by the wheel-end system. The maximum torque value recovered by the system in series mode and parallel mode is the same, which is equal to the maximum charging power of the battery * 9550 / wheel speed;

[0053] 2. Calculate the coasting energy recovery torque, and calculate the recovery torque based on the throttle and vehicle speed;

[0054] 3. The actual torque calculation at the wheel end is equal to the actual output torque of the clutch multiplied by the current gear ratio plus the drive motor torque multiplied by the motor gear ratio;

[0055] 4. Calculate the torque of the drive motor (generated by the engine). The actual wheel end torque minus the drive motor torque wheel end torque;

[0056] 5. Calculate the maximum capacity limit of electric brake recovery, based on the maximum torque value recovered by the wheel-end system, the wheel-end torque recovered by coasting, and the wheel-end torque generated by the drive motor (the part generated by the engine to the drive motor);

[0057] 6. Calculate the maximum power generation capacity limit of the generator based on the available power of the battery pack and the actual current available power of the drive motor.

[0058] Vehicle strategy implementation:

[0059] 1. When the driver releases the accelerator and then steps on the brake during driving. When the accelerator is released, the vehicle is in a gliding state. When the vehicle is in series or pure electric mode, the drive motor torque is equal to the wheel-end gliding torque, and the drive motor's generating torque (engine part) is 0. When the vehicle is in parallel mode, the drive motor torque is equal to the wheel-end gliding torque plus the drive motor's generating torque (engine part).

[0060] 2. After braking, the electric brake starts to request negative power generation torque. The available torque of the electric brake is equal to the system's maximum recovery torque minus the coasting recovery torque minus the drive motor power generation torque (engine part). The negative torque requested by the electric brake must be limited to the available torque range of the electric brake.

[0061] 3. Energy distribution principle after braking: Based on the available power of the battery pack, energy is allocated to the drive motor first. The generator dynamically adjusts its own allowable charging torque according to the actual electric power of the drive motor and the available power of the battery pack, so as to ensure that the actual power usage of the battery pack is within its own available power range.

[0062] See also Figure 4 , the third embodiment of the present invention provides:

[0063] A vehicle braking energy recovery control system, wherein the system comprises:

[0064] A detection module, configured to calculate in real time a maximum recovery torque value corresponding to a wheel-end system inside the hybrid vehicle when detecting in real time that the hybrid vehicle is in a running state;

[0065] A first processing module is used to calculate in real time the coasting energy recovery torque and the driving motor power generation torque generated during the operation of the hybrid vehicle, and calculate in real time the corresponding braking energy recovery available electric power according to the maximum recovery torque value, the coasting energy recovery torque and the driving motor power generation torque;

[0066] A second processing module is used to calculate in real time based on preset rules the maximum capacity limit of electric braking recovery and the maximum power generation capacity limit of the generator corresponding to the hybrid vehicle;

[0067] The third processing module limits the braking energy recovery request torque and the generator request torque calculated corresponding to the hybrid vehicle according to the maximum capacity limit of the electric braking recovery and the maximum power generation capacity limit of the generator to complete the corresponding braking energy recovery control.

[0068] A fourth embodiment of the present invention provides a computer, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the vehicle braking energy recovery control method as described above when executing the computer program.

[0069] A fifth embodiment of the present invention provides a readable storage medium having a computer program stored thereon, wherein when the program is executed by a processor, the vehicle braking energy recovery control method as described above is implemented.

[0070] In summary, the vehicle braking energy recovery control method and system provided in the above embodiments of the present invention can solve the problem of overcharging or over-discharging of the braking energy recovery battery pack, and can improve the braking energy recovery efficiency, reduce the energy consumption of the whole vehicle, and increase the cruising range of the whole vehicle.

[0071] It should be noted that the above modules can be functional modules or program modules, and can be implemented by software or hardware. For modules implemented by hardware, the above modules can be located in the same processor; or the above modules can be located in different processors in any combination.

[0072] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as an ordered list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by an instruction execution system, device or apparatus (such as a computer-based system, a system including a processor, or other system that can fetch instructions from an instruction execution system, device or apparatus and execute instructions), or in conjunction with such instruction execution systems, devices or apparatuses. For the purposes of this specification, "computer-readable medium" can be any device that can contain, store, communicate, propagate or transmit a program for use by an instruction execution system, device or apparatus, or in conjunction with such instruction execution systems, devices or apparatuses.

[0073] More specific examples of computer-readable media (a non-exhaustive list) include the following: an electrical connection with one or more wires (electronic device), a portable computer disk case (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable and programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disk read-only memory (CDROM). In addition, the computer-readable medium may even be a paper or other suitable medium on which the program is printed, since the program may be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, deciphering or, if necessary, processing in another suitable manner, and then stored in a computer memory.

[0074] It should be understood that the various parts of the present invention can be implemented by hardware, software, firmware or a combination thereof. In the above-mentioned embodiments, a plurality of steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or their combination: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0075] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0076] The above-described embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the present invention. It should be pointed out that, for a person of ordinary skill in the art, several modifications and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the attached claims.

Claims

1. A vehicle braking energy recovery control method, characterized in that: The method comprises: When it is detected in real time that the hybrid vehicle is in a running state, a maximum recovery torque value corresponding to a wheel-end system inside the hybrid vehicle is calculated in real time; Calculate in real time the coasting energy recovery torque and the driving motor power generation torque generated during the operation of the hybrid vehicle, and calculate in real time the corresponding braking energy recovery available electric power according to the maximum recovery torque value, the coasting energy recovery torque and the driving motor power generation torque; Calculate in real time based on preset rules the maximum capacity limit of electric braking recovery and the maximum power generation capacity limit of the generator corresponding to the hybrid vehicle; According to the electric brake recovery maximum capacity limit and the generator maximum power generation capacity limit, the brake energy recovery request torque and the generator request torque calculated corresponding to the hybrid vehicle are limited to complete the corresponding brake energy recovery control.

2. The vehicle braking energy recovery control method according to claim 1, characterized in that: The method further comprises: When it is detected in real time that the hybrid vehicle is in the series mode or the parallel mode, the maximum regenerative torque value of the hybrid vehicle is equal to the maximum charging power of the battery pack multiplied by 9550 and divided by the wheel speed.

3. The vehicle braking energy recovery control method according to claim 2, characterized in that: The method further comprises: A throttle, vehicle speed, and coasting energy recovery torque mapping table is designed, and the current driving coasting energy recovery torque is calculated according to the throttle and vehicle speed mapping table.

4. The vehicle braking energy recovery control method according to claim 3, characterized in that: The method further comprises: When it is detected in real time that the hybrid vehicle is in a driving state, the actual wheel end torque corresponding to the hybrid vehicle is calculated in real time. The actual wheel end torque is equal to the actual output torque of the clutch multiplied by the gear ratio plus the drive motor torque multiplied by the motor gear ratio.

5. The vehicle braking energy recovery control method according to claim 2, characterized in that: During the driving of the hybrid vehicle, the maximum limit torque of the braking energy recovery is calculated according to the maximum torque recovered by the system, the current coasting energy recovery torque, the actual torque at the wheel end and the actual torque of the driving motor.

6. A vehicle braking energy recovery control system, characterized in that: The system comprises: A detection module, configured to calculate in real time a maximum regenerative torque value corresponding to a wheel-end system inside the hybrid vehicle when it is detected in real time that the hybrid vehicle is in a running state; A first processing module is used to calculate in real time the coasting energy recovery torque and the driving motor power generation torque generated during the operation of the hybrid vehicle, and calculate in real time the corresponding braking energy recovery available electric power according to the maximum recovery torque value, the coasting energy recovery torque and the driving motor power generation torque; A second processing module is used to calculate in real time based on preset rules the maximum capacity limit of electric braking recovery and the maximum power generation capacity limit of the generator corresponding to the hybrid vehicle; The third processing module is used to limit the braking energy recovery request torque and the generator request torque calculated corresponding to the hybrid vehicle according to the maximum capacity limit of the electric braking recovery and the maximum power generation capacity limit of the generator to complete the corresponding braking energy recovery control.

7. A computer comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the vehicle braking energy recovery control method as described in any one of claims 1 to 7 is implemented.

8. A readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the vehicle braking energy recovery control method as described in any one of claims 1 to 7 is implemented.

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