Vehicle braking energy recovery control method, device and equipment and storage medium

Abstract

The invention relates to a whole vehicle braking energy recovery control method and device, equipment and a storage medium. The method comprises the steps that a whole vehicle state signal is obtained; whether energy recovery is triggered or not is judged according to the whole vehicle state signal; under the condition that energy recovery is triggered, the braking torque of the motor is determined; determining a hydraulic brake pressure and an additional brake pressure based on the brake pedal opening and the vehicle speed; according to the working state of the motor, whether the additional braking pressure and the hydraulic braking pressure are output in a superposed mode or not is judged, and the working state of the motor comprises a feedback torque limited state triggered when the deviation between the actual torque of the motor and the braking torque of the motor exceeds a preset condition.

Description

Technical Field

[0001] The present invention relates to the technical field of energy recovery for pure electric vehicles, and in particular to a whole vehicle braking energy recovery control method, device, equipment and storage medium. Background Art

[0002] With the rapid development of new energy vehicles, energy recovery technology has received widespread attention as an important means to improve driving range. Under actual road conditions, especially in congested and urban areas, vehicles often need to brake and accelerate repeatedly, and the energy consumption at this time is much higher than that when driving at a constant speed. Compared with the characteristics of traditional fuel vehicle engines that do not have energy recovery conditions, new energy vehicles can recover energy during braking through the drive motor, convert the kinetic energy during braking into electrical energy, and further store it in the power battery.

[0003] At present, new energy vehicles generally use the coordinated method of motor braking and hydraulic braking to realize the braking function of the whole vehicle. During the braking process, the common vehicle controller cannot actively adjust the hydraulic braking force, and can only superimpose the motor braking torque on the basis of maintaining the original hydraulic braking force to achieve energy recovery. When the braking force is too large, the motor braking torque is adjusted through calibration means to ensure the smoothness and safety of vehicle braking.

[0004] The above-mentioned braking method has obvious shortcomings: since the hydraulic braking force is not adjustable, it is difficult to flexibly allocate the proportion of electric motor force and hydraulic braking force according to actual working conditions during braking; at the same time, due to the limitations of braking deceleration and hydraulic braking force, the motor cannot fully exert its maximum braking capacity, which greatly limits the energy recovery efficiency. Especially under mild braking conditions, due to the large proportion of hydraulic braking force, a large amount of kinetic energy is lost in the form of heat energy, and the energy recovery efficiency is low.

[0005] In addition, existing brake energy recovery control strategies often fail to fully consider the combined impact of factors such as vehicle operating conditions, motor status, and battery status, and are unable to achieve optimal energy recovery effects. Summary of the invention

[0006] The invention discloses a whole vehicle braking energy recovery control method, device, equipment and storage medium, aiming to solve the technical problems existing in the prior art.

[0007] The present invention adopts the following technical solutions:

[0008] In a first aspect, an embodiment of the present invention provides a vehicle braking energy recovery control method, the method comprising:

[0009] Get vehicle status signal;

[0010] Determining whether to trigger energy recovery according to the vehicle status signal;

[0011] Determine the motor braking torque when energy recovery is triggered;

[0012] Determine hydraulic brake pressure and additional brake pressure based on brake pedal opening and vehicle speed;

[0013] According to the working state of the motor, it is determined whether to superimpose the additional braking pressure and the hydraulic braking pressure and output them, wherein the working state of the motor includes a feedback torque limited state triggered when the deviation between the actual torque of the motor and the braking torque of the motor exceeds a preset condition.

[0014] In some embodiments, the vehicle status signal includes:

[0015] At least one of vehicle high voltage status, battery charge status, accelerator pedal opening, brake pedal opening, gear status, motor speed, vehicle speed, fault level, anti-lock braking system working status and parking brake request information.

[0016] In some embodiments, the step of determining whether to trigger energy recovery according to the vehicle status signal includes:

[0017] Determining whether the vehicle status signal meets a preset safety condition;

[0018] Determining whether the vehicle status signal satisfies a preset energy conversion condition;

[0019] When both the safety condition and the energy conversion condition are met, energy recovery is triggered.

[0020] In some embodiments, the step of determining the motor braking torque includes:

[0021] Determine the motor target braking torque based on the brake pedal opening and the vehicle speed;

[0022] Comparing the motor target braking torque with a preset torque limit and a system maximum capacity torque value;

[0023] The motor braking torque is determined according to the comparison result.

[0024] In some embodiments, the determination of the maximum capacity torque value of the system includes:

[0025] Get the maximum power allowed by the battery and the current motor efficiency;

[0026] Determine a first motor torque based on the maximum allowable power of the battery and the current motor efficiency;

[0027] Obtaining the external characteristic torque of the motor as the second motor torque;

[0028] The larger value of the first motor torque and the second motor torque is selected, and the selected motor torque is corrected based on the fault level to obtain the maximum capacity torque value of the system.

[0029] In some embodiments, the determination of the hydraulic brake pressure includes:

[0030] Acquire the brake pedal opening and the vehicle speed, and determine the initial hydraulic brake pressure based on a preset first pressure association model;

[0031] The initial hydraulic brake pressure is compared with a preset pressure limit to determine the hydraulic brake pressure.

[0032] In some embodiments, the determination of the additional brake pressure includes:

[0033] The brake pedal opening and the vehicle speed are acquired, and the additional brake pressure is determined based on a preset second pressure correlation model.

[0034] In some embodiments, the triggering of the feedback torque limited state includes:

[0035] Detecting a deviation value between the actual torque of the motor and the braking torque of the motor;

[0036] When the deviation value exceeds the preset difference value, the timing is started;

[0037] When the timing reaches a preset time, the feedback torque limited state is triggered.

[0038] In some embodiments, it also includes:

[0039] outputting a superposition value of the hydraulic brake pressure and the additional brake pressure in the feedback torque limited state;

[0040] When the deviation value is smaller than the preset difference value, the feedback torque limited state is released, and only the hydraulic brake pressure is output.

[0041] In a second aspect, an embodiment of the present invention provides a vehicle braking energy recovery control device, comprising:

[0042] The vehicle status acquisition module is used to obtain the vehicle status signal;

[0043] An energy recovery judgment module, used to judge whether to trigger energy recovery according to the vehicle status signal;

[0044] A braking torque determination module, used to determine the motor braking torque when energy recovery is triggered;

[0045] a brake pressure determination module, for determining a hydraulic brake pressure and an additional brake pressure based on a brake pedal opening and a vehicle speed;

[0046] The pressure output control module is used to determine whether to superimpose the additional braking pressure and the hydraulic braking pressure and output them according to the working state of the motor, wherein the working state of the motor includes a feedback torque limited state triggered when the deviation between the actual torque of the motor and the braking torque of the motor exceeds a preset condition.

[0047] In a third aspect, an embodiment of the present invention provides an electronic device, including:

[0048] Processor; and

[0049] A memory arranged to store computer executable instructions which, when executed, cause the processor to perform a method as described in any one of the above.

[0050] In a fourth aspect, an embodiment of the present invention further provides a computer-readable storage medium, which stores one or more programs. When the one or more programs are executed by an electronic device including multiple applications, the electronic device executes any of the methods described above.

[0051] One embodiment of the above invention has the following advantages or beneficial effects:

[0052] The embodiments of the present invention mainly provide a whole vehicle braking energy recovery control method, device, equipment and storage medium. Compared with the prior art, the embodiments of the present invention obtain the whole vehicle status signal in real time and judge the energy recovery conditions, and trigger energy recovery when the safety conditions and energy conversion conditions are met, thereby ensuring the safety and reliability of the energy recovery process. At the same time, the method combines the brake pedal opening and vehicle speed to determine the motor braking torque and braking pressure, thereby ensuring the linearity and smoothness of the braking process.

[0053] Furthermore, the embodiment of the present invention sets a judgment mechanism for the feedback torque limited state. By detecting the deviation value and duration of the motor actual torque and the motor braking torque, it is possible to timely find the working condition where the motor cannot reach the target braking torque. After the feedback torque limited state is triggered, the hydraulic braking pressure and the additional braking pressure are promptly output in a superimposed manner for compensation, which effectively avoids the problems of discontinuous braking force or increased braking distance of the whole vehicle caused by insufficient motor braking force, and improves the safety and reliability of vehicle braking.

[0054] In addition, when determining the maximum capacity torque value of the system, the present invention comprehensively considers multiple factors such as the maximum allowable power of the battery, the motor efficiency, the external characteristic torque of the motor, and makes corrections according to the fault level, so that the execution of energy recovery braking is more precise and controllable, giving full play to the advantages of braking energy recovery in new energy vehicles. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments, which constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions explain the present invention and do not constitute improper limitations on the present invention. In the drawings:

[0056] Figure 1 A flow chart of a vehicle braking energy recovery control method provided by an embodiment of the present invention;

[0057] Figure 2 A structural block diagram of a vehicle braking energy recovery control device provided in one embodiment of the present invention. DETAILED DESCRIPTION

[0058] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the specific embodiments of the present invention and the corresponding drawings. In the description of the present invention, it should be noted that the term "or" is usually used in the sense of including "and / or", unless the content clearly indicates otherwise.

[0059] Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0060] In the existing energy recovery control technology for new energy vehicles, the brake controller is usually unable to actively adjust the hydraulic braking force and can only achieve energy recovery by superimposing the motor braking torque on the basis of maintaining the original hydraulic braking force. This control method makes it difficult to flexibly allocate the proportion of motor braking force and hydraulic braking force according to actual working conditions, especially under mild braking conditions. Due to the large proportion of hydraulic braking force, a large amount of kinetic energy is lost in the form of heat energy, resulting in low energy recovery efficiency. In addition, due to the lack of comprehensive consideration of factors such as vehicle working conditions, motor status, and battery status, the existing control strategy cannot achieve the optimal energy recovery effect, and may also have unreasonable braking force distribution problems, affecting the smoothness of vehicle braking.

[0061] In order to solve the deficiencies in the prior art, an embodiment of the present invention provides a vehicle braking energy recovery control method suitable for new energy vehicles. The control method is preferably executed by a vehicle controller VCU. As the core control unit of the vehicle, the VCU can communicate with various vehicle control units such as the brake controller BCU, the motor controller MCU, and the battery management system BMS to obtain the vehicle status signal in real time. Since the VCU has sufficient computing and processing capabilities, it can quickly complete the judgment of energy recovery conditions, the distribution calculation of braking force, and the issuance of control instructions based on the various status signals obtained, thereby realizing unified and coordinated control of the vehicle braking energy recovery process.

[0062] like Figure 1 In one embodiment of the present invention, the vehicle braking energy recovery control method at least includes the following steps S110 to S150.

[0063] Step S110, obtaining the vehicle status signal.

[0064] Acquiring the vehicle status signal is the basis for realizing energy recovery control. In one embodiment of the present invention, the vehicle status signal includes one or more of the following:

[0065] Vehicle high-voltage status, SoC status, accelerator pedal opening, brake pedal opening, gear status, motor speed, vehicle speed, fault level, ABS system working status and EPB request information.

[0066] In one embodiment of the present invention, the vehicle status signal at least obtains all of the above signals.

[0067] Specifically, the vehicle high-voltage state reflects whether the vehicle high-voltage system is in normal working condition, and its state is directly related to the availability of the energy recovery system; the SoC state represents the remaining power of the power battery, which affects the battery's ability to receive recovered energy; the accelerator pedal opening and the brake pedal opening reflect the driver's operating intention and are important bases for determining the braking demand; the gear state and the motor speed are necessary parameters for determining the motor working point, and both will affect the maximum braking torque that the motor can provide; the vehicle speed information is directly related to the size of the braking energy and the choice of the braking force distribution strategy. In addition, the fault level information can be used to adjust the control strategy in time to ensure the safe and reliable operation of the system under different working conditions; the ABS system working state can reflect whether the wheel anti-lock braking system is involved, which will affect the execution of energy recovery; and the EPB request information reflects the working requirements of the parking brake system. The above status signals are important bases for ensuring the braking safety of the vehicle.

[0068] By collecting the above status signals, the control system can fully grasp the working status of the entire vehicle, lay the foundation for subsequent braking force distribution and energy recovery control, and help achieve safe and efficient braking energy recovery.

[0069] Step S120: determine whether to trigger energy recovery according to the vehicle status signal.

[0070] In one embodiment of the present invention, in order to ensure the safety and effectiveness of energy recovery, after obtaining the vehicle status signal, it is necessary to make a comprehensive judgment on the vehicle status signal. When making the judgment, it is judged whether the vehicle status signal meets the preset safety conditions and whether the vehicle status signal meets the preset energy conversion conditions. When both the safety conditions and the energy conversion conditions are met, energy recovery is triggered, otherwise only hydraulic braking is performed.

[0071] In one embodiment of the present invention, the above safety conditions refer to the vehicle high voltage flag being at a high level, the fault level being less than level 1 (i.e., the system has no serious faults), the ABS system being in a non-working state (i.e., the wheel anti-lock braking condition has not occurred), and the EPB not receiving a parking brake request, etc. These conditions are set mainly from the perspective of vehicle safety to ensure that the energy recovery process does not cause safety hazards.

[0072] In one embodiment of the present invention, the above energy conversion conditions include: the SoC value is within a preset range (e.g., 20% to 90%), the accelerator pedal opening is 0 (i.e., the driver has not stepped on the accelerator pedal), the brake pedal opening is greater than 0 (i.e., the driver has a braking demand), the gear is in D gear or R gear (i.e., the vehicle is in a forward or reverse state), and the motor speed and vehicle speed are both within a preset range. These conditions are set mainly from the perspective of the feasibility and efficiency of energy conversion to ensure that the energy recovery process can be carried out effectively.

[0073] Only when both safety conditions and energy conversion conditions are met will the VCU trigger the energy recovery function, at which point the motor will participate in the braking process and recover energy; if any of the conditions are not met, only conventional hydraulic braking will be performed to ensure the safety and reliability of the braking process. This dual judgment mechanism can effectively avoid energy recovery operations under improper working conditions and improve the safety and reliability of the vehicle's braking energy recovery control.

[0074] Step S130: When energy recovery is triggered, determine the motor braking torque.

[0075] In one embodiment of the present invention, the motor target braking torque is first determined based on the brake pedal opening and the vehicle speed, and then the motor target braking torque is compared with a preset torque limit and a system maximum capacity torque value. Based on the comparison result, a larger value is selected as the motor braking torque to ensure that the motor can output sufficient braking torque to achieve the optimal braking effect within the range allowed by the system.

[0076] It should be noted that the motor braking torque in this step refers to the command value sent to the motor during the control process; the actual motor torque in the subsequent steps refers to the feedback value of the motor during actual operation obtained by the sensor, which is used to evaluate the control effect and perform the next step of control optimization.

[0077] In one embodiment of the present invention, after obtaining the current brake pedal opening and vehicle speed, the motor target braking torque is determined from the vehicle speed-brake pedal opening correlation model. In practical applications, the correlation model is specifically configured as a two-dimensional lookup table. After obtaining the current vehicle speed and brake pedal opening, the system uses these two values ​​as inputs to the lookup table and obtains the corresponding motor target braking torque value through interpolation calculation. Specifically, if the currently collected vehicle speed and brake pedal opening values ​​just correspond to discrete points in the lookup table, the corresponding torque value is directly read; if the two input values ​​fall between the discrete points of the lookup table, the system uses a two-dimensional linear interpolation algorithm for calculation: first interpolate in the vehicle speed direction, then interpolate in the brake pedal opening direction (or vice versa), and finally obtain the motor target braking torque under the current working condition.

[0078] In one embodiment of the present invention, the preset torque limit value can be set to different values ​​according to actual project requirements, which will not be specifically limited here.

[0079] In one embodiment of the present invention, when determining the maximum capacity torque value of the system, it is first necessary to obtain and process the relevant parameters of the battery. Specifically, the system collects the battery current, voltage and maximum charging power in real time, and performs limiting filtering on these three parameters respectively to eliminate sampling noise and mutation effects, and obtains the maximum allowable power of the battery after processing.

[0080] In one embodiment of the present invention, after obtaining the maximum allowable power of the battery, the motor efficiency needs to be determined. Specifically, the system obtains the speed and torque of the motor at the current working point, substitutes these two parameters into the two-dimensional lookup table of motor efficiency, obtains the motor efficiency at the current working point through two-dimensional interpolation calculation, and then calculates the first motor torque based on the maximum allowable power of the battery and the motor efficiency.

[0081] In one embodiment of the present invention, the system also needs to obtain the motor external characteristic torque as the second motor torque, which reflects the maximum braking torque limited by the motor's own capacity. After obtaining the first motor torque and the second motor torque, the larger value is selected between the first motor torque and the second motor torque to maximize energy recovery under the premise of ensuring system safety, and then determine the correction coefficient according to the fault level. The correction coefficient is 0 to 1, and the correction coefficient increases with the increase of the fault level to ensure the safety of the system under different working conditions. The correction coefficient is multiplied by the selected motor torque to obtain the system's maximum capacity torque value.

[0082] Step S140: Determine the hydraulic brake pressure and the additional brake pressure based on the brake pedal opening and the vehicle speed.

[0083] Specifically, the process of determining the hydraulic brake pressure and the additional brake pressure based on the brake pedal opening and the vehicle speed includes two independent control branches, wherein the hydraulic brake pressure is the brake pressure applied by the hydraulic brake system, and the additional brake pressure is the hydraulic brake pressure that needs to be additionally applied to compensate for insufficient motor braking force.

[0084] In one embodiment of the present invention, when determining the hydraulic brake pressure, the brake pedal opening and the vehicle speed are first obtained, and the initial hydraulic brake pressure is determined based on a preset first pressure association model, and then the initial hydraulic brake pressure is compared with a preset pressure limit and the smaller one is taken to finally determine the hydraulic brake pressure. Specifically, the first pressure association model is in the form of a two-dimensional lookup table. When the system obtains the actual vehicle speed and brake pedal opening, the initial hydraulic brake pressure value under the current working condition can be obtained by performing bilinear interpolation calculation in the two-dimensional lookup table.

[0085] In one embodiment of the present invention, the preset pressure limit is an upper limit value set by the system based on the physical characteristics and safety boundaries of the hydraulic braking system. By taking a smaller value, it can be ensured that the hydraulic braking pressure finally applied will not exceed the system safety threshold, thereby avoiding damage to the hydraulic system or sudden changes in the braking effect due to excessive pressure. By constraining the pressure limit, the system components can be protected while ensuring the braking effect.

[0086] In one embodiment of the present invention, when determining the additional brake pressure, the brake pedal opening and the vehicle speed are first obtained, and then the additional brake pressure is determined based on a preset second pressure association model. Specifically, the second pressure association model is also configured as a two-dimensional lookup table, and by performing bilinear interpolation calculation in the two-dimensional lookup table, the additional brake pressure value that needs to be supplemented under the current working condition can be obtained.

[0087] Specifically, the two-dimensional lookup tables configured respectively for the above-mentioned first pressure association model and the second pressure association model are obtained through a large number of vehicle tests and calibrations. The data of the first pressure association model reflects the hydraulic brake pressure required to maintain basic braking performance under different vehicle speeds and pedal openings; and the data of the second pressure association model reflects the additional hydraulic brake pressure that needs to be supplemented when the motor force is insufficient to ensure that the braking performance of the whole vehicle meets the requirements.

[0088] Step S150: determine whether to output the additional braking pressure superimposed on the hydraulic braking pressure according to the motor working state, wherein the motor working state includes a feedback torque limited state triggered when the deviation between the actual motor torque and the motor braking torque exceeds a preset condition.

[0089] Specifically, step S150 mainly deals with the compensation strategy when the actual braking torque of the motor is insufficient, and determines whether additional hydraulic braking force compensation is needed by monitoring the working state of the motor, especially the deviation between the actual torque of the motor and the braking torque of the motor (command value).

[0090] In one embodiment of the present invention, the system adopts different brake pressure output strategies according to different working states. In the feedback torque limited state, the superposition value of the hydraulic brake pressure and the additional brake pressure is output, wherein the additional brake pressure is used to compensate for the shortage of the actual brake torque of the motor; when the deviation value is less than the preset difference, the feedback torque limited state is released, and only the hydraulic brake pressure is output.

[0091] In one embodiment of the present invention, the state switching adopts an asymmetric triggering strategy. Specifically, when switching from the normal state to the feedback torque limited state, two conditions need to be met at the same time: the deviation value exceeds the limit and the duration reaches the preset time; and when returning from the feedback torque limited state to the normal state, only one condition is that the deviation value decreases below the preset difference. This asymmetric switching strategy helps to improve system stability and avoid frequent state switching.

[0092] In one embodiment of the present invention, the deviation between the actual torque of the motor and the braking torque of the motor is continuously detected in real time, and when the deviation exceeds a preset difference, timing is started, and when the timing reaches a preset time, the feedback torque limited state is triggered.

[0093] Specifically, the system collects and feeds back the actual torque signal of the motor through the motor controller, and obtains the motor braking torque command value at the same time, so as to calculate the deviation value between the two, and continuously compares the deviation value with the preset difference value. When it is detected that the deviation value exceeds the preset difference value for the first time, the system immediately starts the timer to start timing and record the duration.

[0094] Furthermore, if the deviation value drops below the preset difference during the timing process, the timer is reset immediately; if the deviation value continues to exceed the preset difference and the timing reaches the preset time, the feedback torque limited state is triggered. The purpose of setting the timing judgment mechanism is to avoid misjudgment due to instantaneous disturbances. By introducing the judgment of the time dimension, the continuous motor braking torque insufficient state can be effectively identified, improving the robustness of the system.

[0095] In one embodiment of the present invention, the calibration of the preset difference and the preset time needs to comprehensively consider the braking performance requirements of the whole vehicle and the system response characteristics. The selection of these parameters must ensure that the state of insufficient motor braking capacity can be identified in time, and avoid being too sensitive and causing frequent triggering of state switching. Specifically, adaptive selection and adjustment can be made according to actual needs, and no specific limitations are given here.

[0096] Based on the above embodiments, the system can judge whether to trigger energy recovery according to the actual working conditions and braking requests to ensure that the energy recovery function is started under appropriate conditions; further, by establishing a reasonable pressure correlation model and setting pressure limits, a compensation strategy for hydraulic brake pressure is formulated to ensure the safety and reliability of the braking system; by real-time monitoring of the motor working state, a judgment mechanism for the motor maximum feedback torque limit flag is formulated to improve the stability of the system. Through the reasonable configuration of the above technical features, the embodiment of the present invention can achieve an energy recovery rate of more than 30% under actual road conditions.

[0097] like Figure 2 In one embodiment of the present invention, a vehicle braking energy recovery control device 200 is also provided, which at least includes a vehicle state acquisition module 210, an energy recovery judgment module 220, a braking torque determination module 230, a braking pressure determination module 240, and a pressure output control module 250.

[0098] In one embodiment of the present invention, the vehicle status acquisition module 210 is used to acquire a vehicle status signal.

[0099] Specifically, the vehicle status signal includes one or more of the following:

[0100] Vehicle high-voltage status, SoC status, accelerator pedal opening, brake pedal opening, gear status, motor speed, vehicle speed, fault level, ABS system working status and EPB request information.

[0101] In one embodiment of the present invention, the vehicle status signal at least obtains all of the above signals.

[0102] In one embodiment of the present invention, the energy recovery determination module 220 is used to determine whether to trigger energy recovery according to the vehicle status signal.

[0103] In one embodiment of the present invention, the energy recovery judgment module 220 is used to respectively judge whether the vehicle status signal meets the preset safety conditions and whether the vehicle status signal meets the preset energy conversion conditions. When both the safety conditions and the energy conversion conditions are met, energy recovery is triggered, otherwise only hydraulic braking is performed.

[0104] In one embodiment of the present invention, the above safety conditions refer to the vehicle high voltage flag being at a high level, the fault level being less than level 1 (i.e., the system has no serious faults), the ABS system being in a non-working state (i.e., the wheel anti-lock braking condition has not occurred), and the EPB not receiving a parking brake request, etc. These conditions are set mainly from the perspective of vehicle safety to ensure that the energy recovery process does not cause safety hazards.

[0105] In one embodiment of the present invention, the above energy conversion conditions include: the SoC value is within a preset range (e.g., 20% to 90%), the accelerator pedal opening is 0 (i.e., the driver has not stepped on the accelerator pedal), the brake pedal opening is greater than 0 (i.e., the driver has a braking demand), the gear is in D gear or R gear (i.e., the vehicle is in a forward or reverse state), and the motor speed and vehicle speed are both within a preset range. These conditions are set mainly from the perspective of the feasibility and efficiency of energy conversion to ensure that the energy recovery process can be carried out effectively.

[0106] In one embodiment of the present invention, the braking torque determination module 230 is used to determine the motor braking torque when energy recovery is triggered.

[0107] In one embodiment of the present invention, the braking torque determination module 230 can determine the motor target braking torque based on the brake pedal opening and the vehicle speed, and then compare the motor target braking torque with the preset torque limit and the system maximum capacity torque value. According to the comparison result, a larger value is selected as the motor braking torque to ensure that the motor can output sufficient braking torque to achieve the optimal braking effect within the range allowed by the system.

[0108] In one embodiment of the present invention, the braking torque determination module 230 can collect the battery current, voltage and maximum charging power in real time, and perform limiting filtering on these three parameters respectively to eliminate sampling noise and mutation effects, and obtain the maximum allowable power of the battery after processing.

[0109] In one embodiment of the present invention, the braking torque determination module 230 can be used to determine the motor efficiency after obtaining the maximum allowable battery power. Specifically, the braking torque determination module 230 can obtain the speed and torque of the motor at the current working point, substitute these two parameters into the two-dimensional lookup table of the motor efficiency, obtain the motor efficiency at the current working point through two-dimensional interpolation calculation, and then calculate the first motor torque according to the maximum allowable battery power and the motor efficiency.

[0110] In one embodiment of the present invention, the braking torque determination module 230 can also be used to obtain the motor external characteristic torque as the second motor torque, which reflects the maximum braking torque limited by the motor's own capacity. After obtaining the first motor torque and the second motor torque, the larger value is selected from the first motor torque and the second motor torque to maximize energy recovery under the premise of ensuring system safety, and then determine the correction coefficient according to the fault level. The correction coefficient is 0 to 1, and the correction coefficient increases with the increase of the fault level to ensure the safety of the system under different working conditions. The correction coefficient is multiplied by the selected motor torque to obtain the system maximum capacity torque value.

[0111] In one embodiment of the present invention, the brake pressure determination module 240 is configured to determine the hydraulic brake pressure and the additional brake pressure based on the brake pedal opening and the vehicle speed.

[0112] In one embodiment of the present invention, when determining the hydraulic brake pressure, the brake pressure determination module 240 first obtains the brake pedal opening and the vehicle speed, determines the initial hydraulic brake pressure based on a preset first pressure association model, then compares the initial hydraulic brake pressure with the preset pressure limit and takes the smaller one, and finally determines the hydraulic brake pressure.

[0113] In one embodiment of the present invention, when determining the additional braking pressure, the braking pressure determination module 240 first obtains the brake pedal opening and the vehicle speed, and then determines the additional braking pressure based on a preset second pressure association model.

[0114] In one embodiment of the present invention, the pressure output control module 250 is used to determine whether to superimpose and output the additional braking pressure with the hydraulic braking pressure according to the working state of the motor, wherein the working state of the motor includes a feedback torque limited state triggered when the deviation between the actual torque of the motor and the braking torque of the motor exceeds a preset condition.

[0115] In one embodiment of the present invention, the pressure output control module 250 can adopt different brake pressure output strategies according to different working states. In the feedback torque limited state, the superposition value of the hydraulic brake pressure and the additional brake pressure is output, wherein the additional brake pressure is used to compensate for the shortage of the actual brake torque of the motor; when the deviation value is less than the preset difference, the feedback torque limited state is released, and only the hydraulic brake pressure is output.

[0116] In one embodiment of the present invention, the pressure output control module 250 is used to continuously detect the deviation between the actual torque of the motor and the braking torque of the motor in real time, start timing when the deviation exceeds a preset difference, and trigger the feedback torque limited state when the timing reaches a preset time.

[0117] It should be noted that the vehicle braking energy recovery control device 200 provided in the above embodiment and the embodiment of the vehicle braking energy recovery control method belong to the same concept, and the specific implementation process is detailed in the embodiment of the control method, which will not be repeated here.

[0118] In one embodiment of the present invention, a new energy vehicle is also provided. The vehicle is provided with the above-mentioned whole vehicle braking energy recovery control device 200 and is capable of executing the above-mentioned whole vehicle braking energy recovery control method.

[0119] An embodiment of the present invention further provides an electronic device, which includes a memory and a processor, wherein a computer program executed by the processor is stored in the memory, and when the computer program is executed by the processor, the processor executes the vehicle braking energy recovery control method described above. Various applications and various data, such as various data used and / or generated by the application, may also be stored in the memory. The processor may be a central processing unit (CPU), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), or other forms of processing units having data processing capabilities and / or instruction execution capabilities.

[0120] The embodiment of the present invention further provides a computer-readable storage medium, on which a computer program executed by a processor is stored. When the computer program is executed by the processor, the processor executes the vehicle braking energy recovery control method as described above. Exemplarily, the computer storage medium may include a memory card of a smart phone, a storage component of a tablet computer, a hard disk of a personal computer, a read-only memory (ROM), an erasable programmable read-only memory (EPROM), a portable compact disk read-only memory (CD-ROM), a USB memory, or any combination of the above storage media. The computer-readable storage medium may be any combination of one or more computer-readable storage media.

[0121] Although example embodiments have been described herein with reference to the accompanying drawings, it should be understood that the above example embodiments are merely exemplary and are not intended to limit the scope of the present application to this. Those of ordinary skill in the art may make various changes and modifications therein without departing from the scope and spirit of the present application. All these changes and modifications are intended to be included within the scope of the present application as required by the appended claims.

[0122] In the description provided herein, a large number of specific details are described. However, it is understood that the embodiments of the present application can be practiced without these specific details. In some instances, well-known methods, structures and techniques are not shown in detail so as not to obscure the understanding of this description.

[0123] Similarly, it should be understood that in order to streamline the present application and help understand one or more of the various inventive aspects, in the description of the exemplary embodiments of the present application, the various features of the present application are sometimes grouped together into a single embodiment, figure, or description thereof. However, the method of the present application should not be interpreted as reflecting the following intention: the claimed application requires more features than the features clearly stated in each claim. More specifically, as reflected in the corresponding claims, the inventive point is that the corresponding technical problem can be solved with features less than all the features of a single disclosed embodiment. Therefore, the claims following the specific embodiment are hereby explicitly incorporated into the specific embodiment, wherein each claim itself serves as a separate embodiment of the present application.

[0124] It will be understood by those skilled in the art that, except for mutually exclusive features, all features disclosed in this specification (including the accompanying claims, abstracts and drawings) and all processes or units of any method or device disclosed in this specification may be combined in any combination. Unless otherwise expressly stated, each feature disclosed in this specification (including the accompanying claims, abstracts and drawings) may be replaced by an alternative feature that provides the same, equivalent or similar purpose.

[0125] The embodiments of the present invention are described above in conjunction with the accompanying drawings, but the present invention is not limited to the above-mentioned specific implementation modes, which are merely illustrative rather than restrictive. Under the guidance of the present invention, ordinary technicians in this field can also make many forms without departing from the scope of protection of the present invention and the claims, all of which are within the protection of the present invention.

Claims

1. A vehicle braking energy recovery control method, characterized in that: include: Get vehicle status signal; Determining whether to trigger energy recovery according to the vehicle status signal; Determine the motor braking torque when energy recovery is triggered; Determine hydraulic brake pressure and additional brake pressure based on brake pedal opening and vehicle speed; According to the working state of the motor, it is determined whether to superimpose the additional braking pressure and the hydraulic braking pressure and output them, wherein the working state of the motor includes a feedback torque limited state triggered when the deviation between the actual torque of the motor and the braking torque of the motor exceeds a preset condition.

2. The vehicle braking energy recovery control method according to claim 1, characterized in that: The vehicle status signal includes: At least one of vehicle high voltage status, battery charge status, accelerator pedal opening, brake pedal opening, gear status, motor speed, vehicle speed, fault level, anti-lock braking system working status and parking brake request information.

3. The vehicle braking energy recovery control method according to claim 1, characterized in that: The step of determining whether to trigger energy recovery according to the vehicle status signal includes: Determining whether the vehicle status signal meets a preset safety condition; Determining whether the vehicle status signal satisfies a preset energy conversion condition; When both the safety condition and the energy conversion condition are met, energy recovery is triggered.

4. The vehicle braking energy recovery control method according to claim 1, characterized in that: The step of determining the motor braking torque includes: Determine the motor target braking torque based on the brake pedal opening and the vehicle speed; Comparing the motor target braking torque with a preset torque limit and a system maximum capacity torque value; The motor braking torque is determined according to the comparison result.

5. The vehicle braking energy recovery control method according to claim 4, characterized in that: The determination of the maximum capacity torque value of the system includes: Get the maximum power allowed by the battery and the current motor efficiency; Determine a first motor torque based on the maximum allowable power of the battery and the current motor efficiency; Obtaining the external characteristic torque of the motor as the second motor torque; The larger value of the first motor torque and the second motor torque is selected, and the selected motor torque is corrected based on the fault level to obtain the maximum capacity torque value of the system.

6. The vehicle braking energy recovery control method according to claim 1, characterized in that: The determination of the hydraulic brake pressure includes: Acquire the brake pedal opening and the vehicle speed, and determine the initial hydraulic brake pressure based on a preset first pressure association model; The initial hydraulic brake pressure is compared with a preset pressure limit to determine the hydraulic brake pressure.

7. The vehicle braking energy recovery control method according to claim 1, characterized in that: The determination of the additional brake pressure includes: The brake pedal opening and the vehicle speed are acquired, and the additional brake pressure is determined based on a preset second pressure correlation model.

8. The vehicle braking energy recovery control method according to claim 1, characterized in that: The triggering of the feedback torque limited state includes: Detecting a deviation value between the actual torque of the motor and the braking torque of the motor; When the deviation value exceeds the preset difference value, the timing is started; When the timing reaches a preset time, the feedback torque limited state is triggered.

9. The vehicle braking energy recovery control method according to claim 8, characterized in that: Also includes: outputting a superposition value of the hydraulic brake pressure and the additional brake pressure in the feedback torque limited state; When the deviation value is smaller than the preset difference value, the feedback torque limited state is released, and only the hydraulic brake pressure is output.

10. A vehicle braking energy recovery control device, characterized in that: include: The vehicle status acquisition module is used to obtain the vehicle status signal; An energy recovery judgment module, used to judge whether to trigger energy recovery according to the vehicle status signal; A braking torque determination module, used to determine the motor braking torque when energy recovery is triggered; a brake pressure determination module, for determining a hydraulic brake pressure and an additional brake pressure based on a brake pedal opening and a vehicle speed; The pressure output control module is used to determine whether to superimpose the additional braking pressure and the hydraulic braking pressure and output them according to the working state of the motor, wherein the working state of the motor includes a feedback torque limited state triggered when the deviation between the actual torque of the motor and the braking torque of the motor exceeds a preset condition.

11. An electronic device, characterized in that: include: processor; as well as A memory arranged to store computer executable instructions which, when executed, cause the processor to perform a method as claimed in any one of claims 1 to 9.

12. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores one or more programs, which, when executed by an electronic device including a plurality of application programs, enable the electronic device to execute the method according to any one of claims 1 to 9.

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