Method and system for calculating braking energy recovery capacity of electric vehicle

Abstract

The invention provides a method and system for calculating the braking energy recycling capacity of an electric automobile, and belongs to the technical field of braking energy recycling. The method for calculating the braking energy recycling capacity of the electric automobile comprises the steps that based on the current state of the automobile, the current torque allowed to be recycled by a power assembly is determined; the sliding energy recovery torque is calculated, and the initial braking recovery torque capacity is obtained by subtracting the sliding energy recovery torque from the torque allowed to be recovered by the current power assembly; and the initial brake recovery torque capacity is corrected according to the vehicle speed and the driving torque, and the corrected initial brake recovery torque capacity is the brake recovery torque upper limit value allowed by the IBC. And the PDCU calculates the available capacity of the electric braking system to the IBC, so that the over-charging and over-discharging of the battery can be effectively avoided, and the driving experience of the whole vehicle is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of brake energy recovery, in particular to a method and system for calculating brake energy recovery capability of an electric vehicle. BACKGROUND

[0002] With the rapid development of electric vehicles, brake energy recovery technology, as an effective method to improve energy utilization efficiency, has been widely used in electric vehicles.

[0003] Energy recovery on electric vehicles is generally divided into coasting energy recovery and brake energy recovery. Coasting energy recovery is generally controlled by PDCU (Power Domain Control Unit, vehicle controller), and brake energy recovery is generally controlled by IBC (Integrated Brake Control, chassis domain controller). When controlling brake energy recovery, IBC needs to refer to the brake recovery capability of PDCU, and the brake recovery capability of PDCU is limited for recovery. Therefore, the brake recovery capability calculated by PDCU is crucial, but the brake recovery capability calculated by PDCU in the prior art has certain defects. SUMMARY

[0004] The present application aims to solve at least one of the technical problems existing in the prior art, and provides a method and system for calculating brake energy recovery capability of an electric vehicle.

[0005] In a first aspect, the present application provides a method for calculating brake energy recovery capability of an electric vehicle, comprising:

[0006] determining the torque allowed to be recovered by the current powertrain based on the current state of the vehicle;

[0007] calculating the coasting energy recovery torque, and the initial brake recovery torque capability is the torque allowed to be recovered by the current powertrain minus the coasting energy recovery torque;

[0008] correcting the initial brake recovery torque capability according to the vehicle speed and the driving torque, and the corrected initial brake recovery torque capability is the upper limit value of the brake recovery torque allowed by IBC.

[0009] The method for calculating brake energy recovery capability of an electric vehicle comprises:

[0010] determining whether the current vehicle is in a ready state;

[0011] if the current vehicle is in a ready state, calculating the current recoverable power of the battery according to the current charge allowable power, the charge allowable voltage and the charge allowable recovery current of the battery, and calculating the recoverable torque of the battery according to the current recoverable power of the battery;

[0012] According to the current speed of the motor, the external characteristic parameters of the motor recovery working condition are determined, and according to the maximum torque that the drive shaft can bear, the maximum recoverable torque of the power system is determined ;

[0013] According to the maximum recoverable torque of the power system and the battery recoverable torque, the torque allowed to be recovered by the current power assembly is determined.

[0014] Among them, the battery current recoverable power is calculated according to the battery current charging allowed power, charging allowed voltage and charging allowed recovery current

[0015] According to the battery SOC, the discharge power allowed by the battery temperature limit And the power consumed by the accessory , the recoverable power of the power system is ;

[0016] According to the current voltage or current of the battery, the maximum recoverable power allowed by the battery is calculated , and the final recoverable power of the power system limited by the battery voltage and current is ;

[0017] When the actual recovery power of the battery exceeds the maximum allowed recovery power of the battery, the recovery power is set to 0.

[0018] Among them, in the pure electric system, the recovery source of the battery is the motor, and the battery recoverable torque is calculated according to the current battery recoverable power

[0019] According to the recovery power , and the least square method is used to calculate the battery recoverable torque of the current motor .

[0020] Among them, the calculation of the coasting energy recovery torque includes:

[0021] The PDCU obtains the coasting energy recovery torque required by the driver according to the current vehicle speed, the accelerator pedal opening degree and the recovery mode.

[0022] Among them, the initial brake recovery torque capacity is corrected according to the vehicle speed and the drive torque, including:

[0023] In the correction of vehicle speed, the correction formula is: ; wherein is the correction coefficient determined according to the vehicle speed and the driving mode;

[0024] In the correction of the driving torque, the current driving condition is determined according to the current vehicle speed, the accelerator pedal opening degree and the gear information, if the current condition is in the driving state, the brake recovery torque capacity is decreased to 0 with a certain gradient, if the current condition is in the recovery state, the brake recovery torque capacity is increased to .

[0025] The current driving condition is determined according to the current vehicle speed, the accelerator pedal opening degree and the gear information, and includes:

[0026] The vehicle is in the ready state;

[0027] When the driver requests torque is greater than , the driving condition is in the driving state, is the minimum output torque in the D gear state; or when the driver requests torque is less than , the driving condition is in the driving state,

[0028] When the driver requests torque is less than , the driving condition is in the recovery state; or when the driver requests torque is greater than , the driving condition is in the recovery state.

[0029] In the second aspect, the embodiment of the present application provides a brake energy recovery capacity calculation system of an electric vehicle, comprising:

[0030] A torque determination unit is configured to determine the current powertrain allowed recovery torque based on the current state of the vehicle.

[0031] An initial brake recovery torque capacity calculation unit is configured to calculate the coasting energy recovery torque, and the initial brake recovery torque capacity is the current powertrain allowed recovery torque minus the coasting energy recovery torque.

[0032] A correction unit is configured to correct the initial brake recovery torque capacity according to the vehicle speed and the driving torque, and the corrected initial brake recovery torque capacity is the upper limit value of the brake recovery torque allowed by the IBC.

[0033] In the third aspect, the embodiment of the present application provides an electronic device, comprising:

[0034] One or more processors;

[0035] A memory is configured to store one or more programs;

[0036] When the one or more programs are executed by the one or more processors, the one or more processors implement any of the above methods.

[0037] In a fourth aspect, an embodiment of the present application provides a computer readable medium, and the computer readable medium stores a computer program, wherein the computer program is executed by a processor to implement the steps in any of the above methods.

[0038] The electric vehicle braking energy recovery capability calculation method and system provided by the application first determines the torque allowed to be recovered by the current power assembly based on the current state of the vehicle, then calculates the coasting energy recovery torque, and subtracts the coasting energy recovery torque from the torque allowed to be recovered by the current power assembly to obtain the initial braking recovery torque capability; then the initial braking recovery torque capability is corrected according to the vehicle speed and the driving torque, and the corrected initial braking recovery torque capability is the braking recovery torque capability allowed by the IBC. The available capability of the electric braking system is calculated by the PDCU for the IBC, which can effectively avoid overcharging and overdischarging of the battery and improve the vehicle driving experience. BRIEF DESCRIPTION OF DRAWINGS

[0039] The accompanying drawings, which are included to provide a further understanding of the application and are incorporated in and constitute a part of this application, illustrate embodiments of the application and serve to explain the principles of the application, and do not limit the application. In the drawings:

[0040] Figure 1 A flowchart of an electric vehicle braking energy recovery capability calculation method provided by an embodiment of the application is shown in the figure;

[0041] Figure 2 An optional specific implementation flowchart of an electric vehicle braking energy recovery capability calculation method provided by an embodiment of the application is shown in the figure;

[0042] Figure 3 An optional specific implementation flowchart of an electric vehicle braking energy recovery capability calculation method provided by an embodiment of the application is shown in the figure;

[0043] Figure 4 An optional specific implementation flowchart of an electric vehicle braking energy recovery capability calculation method provided by an embodiment of the application is shown in the figure;

[0044] Figure 5 A structural block diagram of an electric vehicle braking energy recovery capability calculation system provided by an embodiment of the application is shown in the figure;

[0045] Figure 6 A structural block diagram of an electronic device provided by an embodiment of the application is shown in the figure. DETAILED DESCRIPTION

[0046] For a better understanding of the technical solutions of the present application, the exemplary embodiments of the present application are described below in conjunction with the drawings, which include various details of the embodiments of the present application to help understanding, and should be considered as merely exemplary. Therefore, those of ordinary skill in the art should recognize that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of the present application. Also, for the sake of clarity and conciseness, the description below omits the description of well-known functions and structures.

[0047] In the case of no conflict, each embodiment of the present application and each feature in the embodiments can be combined with each other.

[0048] As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0049] The terms used herein are only used to describe specific embodiments, and are not intended to limit the present application. As used herein, the singular forms "a" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will also be understood that the terms "comprise" and / or "consist of", when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof. The terms "connected" or "coupled" and / or similar terms are not limited to a physical or mechanical connection, but can include an electrical connection, whether direct or indirect.

[0050] Unless otherwise defined, all terms used herein, including technical and scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art. It will also be understood that terms such as those defined in commonly used dictionaries should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and the present application, and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

[0051] In the technical solutions of the present application, the collection, storage, use, processing, transmission, provision and disclosure of user personal information comply with relevant laws and regulations, and do not violate public order and good customs. The use of user data in the technical solutions complies with relevant national laws and regulations (for example, "Information Security Technology Personal Information Security Specification" and the like). For example, appropriate measures are taken for personal information access control; restrictions are given for the display of personal information; the use purpose of personal information does not exceed the direct or reasonably related range; the use of personal information eliminates the explicit identity pointing and avoids precise positioning to a specific individual.

[0052] In the related art, energy recovery on an electric vehicle is generally divided into coasting energy recovery and braking energy recovery, the coasting energy recovery is generally controlled by a PDCU (Power Domain Control Unit), and the braking energy recovery is generally controlled by an IBC (Integrated Brake Control). When the IBC controls the braking energy recovery, the braking recovery capability of the PDCU needs to be referred to, and the braking recovery capability of the PDCU is used as a limit for recovery, so the braking recovery capability calculated by the PDCU is crucial, but the braking recovery capability calculated by the PDCU in the prior art has certain defects.

[0053] The technical problem solved by the present application is that in an electric vehicle, energy recovery can increase the cruising range of the electric vehicle. Energy recovery is generally controlled by two controllers, PDCU controls coasting energy recovery, and IBC controls braking energy recovery. PDCU, as the brain of the vehicle, interacts with BMS (Battery Management System) and MCU (Motor Control Unit), and is more aware of the system capability. The available capability of the electric braking system calculated by PDCU is provided to IBC, which can effectively avoid overcharging and overdischarging of the battery and improve the driving experience of the vehicle.

[0054] To solve at least one of the technical problems in the related art described above, the present application provides an electric vehicle braking energy recovery capability calculation method and system. Wherein: Figure 1 A flowchart of an electric vehicle braking energy recovery capability calculation method provided by an embodiment of the present application is provided; Figure 2 An optional specific implementation flowchart of an electric vehicle braking energy recovery capability calculation method provided by an embodiment of the present application is provided; Figure 3 An optional specific implementation flowchart of an electric vehicle braking energy recovery capability calculation method provided by an embodiment of the present application is provided; Figure 4 An optional specific implementation flowchart of an electric vehicle braking energy recovery capability calculation method provided by an embodiment of the present application is provided; Figure 5 A block diagram of an electric vehicle braking energy recovery capability calculation system provided by an embodiment of the present application is provided; Figure 6 A block diagram of an electronic device provided by an embodiment of the present application is provided.

[0055] As an embodiment of the present application, the present application provides an electric vehicle braking energy recovery capability calculation method, comprising:

[0056] Based on the current state of the vehicle, determine the torque allowed to be recovered by the current powertrain;

[0057] The initial brake recovery torque capability is the torque allowed to be recovered by the current powertrain minus the coasting energy recovery torque.

[0058] The initial brake recovery torque capability is corrected according to the vehicle speed and the driving torque, and the corrected initial brake recovery torque capability is the upper limit value of the brake recovery torque allowed by the IBC.

[0059] The electric vehicle brake energy recovery capability calculation method provided by the application mainly refers to the recovery torque, which is calculated by calculating the recovery torque. First, based on the current state of the vehicle, the torque allowed to be recovered by the current powertrain is determined; then the coasting energy recovery torque is calculated, and the initial brake recovery torque capability is the torque allowed to be recovered by the current powertrain minus the coasting energy recovery torque; then the initial brake recovery torque capability is corrected according to the vehicle speed and the driving torque, and the corrected initial brake recovery torque capability is the upper limit value of the brake recovery torque allowed by the IBC. The PDCU calculates the available capability of the electric brake system for the IBC, which can effectively avoid overcharging and overdischarging of the battery and improve the vehicle driving experience.

[0060] The torque allowed to be recovered by the current powertrain is determined based on the current state of the vehicle, including:

[0061] Determine whether the current vehicle is in a ready state;

[0062] If it is in the ready state, calculate the current recoverable power of the battery according to the current charging power, charging voltage and charging recovery current allowed by the battery; and calculate the recoverable torque of the battery according to the current recoverable power of the battery;

[0063] Determine the external characteristic parameters of the motor recovery working condition according to the current speed of the motor, and determine the maximum recoverable torque of the power system according to the maximum torque that the driving shaft can withstand ;

[0064] Determine the torque allowed to be recovered by the current powertrain according to the maximum recoverable torque of the power system and the recoverable torque of the battery.

[0065] The current recoverable power of the battery is calculated according to the current charging power, charging voltage and charging recovery current allowed by the battery, including:

[0066] Determine the recoverable power of the power system according to the discharge power allowed by the battery SOC, battery temperature And the power consumed by the accessory , the recoverable power of the power system is ;

[0067] Calculate the maximum recoverable power currently allowed by the battery according to the current voltage or current of the battery , the final recoverable power of the powertrain under the battery voltage and current limits is ;

[0068] When the actual recoverable power of the battery exceeds the maximum allowable recoverable power of the battery, the recoverable power is set to 0.

[0069] Wherein, in the pure electric system, the recoverable source of the battery is the motor, and the calculation of the battery recoverable torque according to the current recoverable power of the battery includes:

[0070] According to the recoverable power , and the battery recoverable torque of the current motor is calculated by the least square method .

[0071] Wherein, the calculation of the coasting energy recovery torque includes:

[0072] The PDCU obtains the coasting energy recovery torque required by the driver according to the current vehicle speed, the accelerator pedal opening degree and the recovery mode.

[0073] Wherein, the initial braking recovery torque capacity is corrected according to the vehicle speed and the driving torque, including:

[0074] In the correction of the vehicle speed, the correction formula is: ; wherein is the correction coefficient determined according to the vehicle speed, the driving mode;

[0075] In the correction of the driving torque, the current driving condition is determined according to the current vehicle speed, the accelerator pedal opening degree and the gear information, if the current condition is in the driving state, the braking recovery torque capacity is decreased to 0 with a certain gradient, if the current condition is in the recovery state, the current value of the braking recovery torque capacity is increased to .

[0076] Wherein, the current driving condition is determined according to the current vehicle speed, the accelerator pedal opening degree and the gear information, including:

[0077] The vehicle is in the ready state;

[0078] When the D gear and the driver's requested torque is greater than , the driving condition is the driving state, is the minimum output torque in the D gear (when the driver steps on the accelerator in the D gear, a positive torque is output, and when the positive torque is greater than a certain value, it is determined that it is in the driving state); or when the R gear, the driver's requested torque is less than , the driving condition is the driving state, The maximum output torque in the R gear state (when the driver steps on the accelerator in the R gear, a negative torque is output, and when the negative torque is less than a certain value, it is determined that it is in the driving state);

[0079] D gear, driver requested torque Less than When the driving condition is the recovery state; or when the driver requested torque is greater than When the driving condition is the recovery state.

[0080] Specifically, the technical problem to be solved by the present application is that in an electric vehicle, energy recovery can increase the cruising range of the electric vehicle. Energy recovery is generally controlled by two controllers, PDCU controls coasting energy recovery, IBC controls braking energy recovery, PDCU as the brain of the whole vehicle, interacts with BMS (Battery Management System) / MCU (Motor Control Unit), and is more clear about the system capability. The available capacity of the electric braking system is calculated by PDCU to IBC, which can effectively avoid overcharging and overdischarging of the battery, and improve the driving experience of the whole vehicle.

[0081] The complete technical solution of the present application is as follows:

[0082] The present application provides a kind of electric vehicle braking energy recovery capability calculation method, refer to Figure 1 , comprising the following steps:

[0083] Based on the current state of the vehicle, the torque allowed to be recovered by the current powertrain is determined. Wherein, the current state includes vehicle ready condition, current speed of motor and corresponding recovery capability under current speed and axle capability, temperature limit, SOC limit, limit from power to torque.

[0084] PDCU calculates coasting energy recovery, and the torque allowed to be recovered by the current powertrain is subtracted from the initial braking recovery capability calculated by PDCU.

[0085] The initial braking recovery capability is corrected according to the vehicle speed and driving torque, and the corrected final braking recovery capability is sent to IBC as the upper limit value of IBC braking energy recovery.

[0086] Based on the current state of the vehicle, the torque allowed to be recovered by the current powertrain is determined, including:

[0087] Determine if the vehicle is in ready state, if yes, calculate the current recoverable power of the battery according to the current charge allowable power, charge allowable voltage, charge allowable recovery current. Determine the motor recovery operating characteristic parameters according to the current motor speed, determine the maximum recoverable torque capacity of the powertrain according to the maximum torque that the drive shaft can withstand If the vehicle is not in ready state, the powertrain capacity is 0.

[0088] Calculate the current recoverable torque of the battery: when the battery SOC is high or the temperature is high, it will affect the charging power of the battery (the charging power is negative), so first limit the allowable discharge power according to the battery SOC and battery temperature, the limited power is , the power consumed by the accessories can be part of the battery recovery capacity, so the recoverable power of the powertrain is . The recovery power of the battery is affected by the battery voltage and current, according to the current voltage or current of the battery, calculate the maximum recoverable power of the battery , the final recoverable power of the powertrain limited by the battery voltage and current is When the actual recovery power of the battery exceeds the maximum allowable recovery power of the battery, the PDCU sets the recovery power to 0 to avoid overcharging the battery.

[0089] In the pure electric system, the recovery source of the battery is the motor, so is the limit of the motor recovery power, based on this, according to the least square method, the torque capacity that the current motor can recover according to the battery condition is calculated .

[0090] The final calculated current powertrain allows to recover the torque . That is, within the capacity range of the motor, battery and drive shaft.

[0091] PDCU calculates the coasting energy recovery, the current powertrain allows to recover the torque minus the coasting recovery calculated by PDCU as the initial brake recovery capacity, including:

[0092] Referring to Figure 2 , energy recovery generally includes two parts, one part is the coasting energy recovery calculated by PDCU , and the other part is the brake energy recovery calculated by IBC. PDCU obtains the coasting energy recovery torque required by the driver according to the current vehicle speed, accelerator pedal opening degree and recovery mode, and the initial brake recovery capacity does not include coasting energy recovery. That is .

[0093] The initial brake recovery capability is corrected according to the vehicle speed and the driving torque, and the corrected brake recovery capability is the final brake recovery capability, which is sent to the IBC as the upper limit value of the IBC brake energy recovery, including:

[0094] In the correction of the vehicle speed, the correction formula is: ;

[0095] Wherein is a correction coefficient determined according to the vehicle speed and the driving mode. The value of may be determined according to the calibration, and the calibration values are as follows:

[0096] 0 10 20 30 40 50 60 80 100 120 140 180 Strong recovery 0 0.1 0.2 0.2 0.2 0.2 0.2 0.2 1 1 1 1 Medium recovery 0 0.1 0.2 0.2 0.2 0.2 0.2 0.2 1 1 1 1 Low recovery 0 0.1 0.2 0.2 0.2 0.2 0.2 0.2 1 1 1 1

[0097] The corrected brake recovery capability is smaller in value than the uncorrected brake recovery capability.

[0098] Referring to Figures 3-4 , in the correction of the driving torque, the current driving condition is determined according to the current vehicle speed, the accelerator pedal opening degree, the gear and other information, if the current condition is in the driving state, the brake recovery capability is decreased to 0 at a certain gradient, and if the current condition is in the recovery condition, the brake recovery capability is increased to ,

[0099] The processing formula after the increase and decrease is:

[0100]

[0101] Wherein is a positive value, representing the value of each period of increase, is a negative value, representing the value of each period of decrease; is the final brake recovery capability allowed to be sent to the IBC, represents the brake recovery capability corrected according to the driving torque; is the difference between the current time and the last time.

[0102] Driving and recovery state judgment: the vehicle is in the ready state, the D gear, and the driver's request torque is greater than , and the driver's request torque is less than when the R gear is in the driving state, and vice versa.

[0103] The technical scheme of the present application has the beneficial effects of:

[0104] ​By accurately calculating the braking recovery capability, the chassis domain controller can determine the upper limit value of the braking energy recovery, limit the braking recovery within the recoverable capability of the battery, effectively avoid overcharging of the battery, and protect the service life of the battery. In addition, by judging the driving and recovery state, the braking recovery capability is corrected, the generation of braking recovery torque is inhibited in the driving working condition (such as the double-foot driving working condition), the rapid torque drop caused by the superposition of the braking recovery torque is avoided, and the adverse driving performance is caused, and the vehicle NVH is improved.

[0105] As an embodiment of the present application, refer to Figure 5 The present application provides an electric vehicle braking energy recovery capability calculation system, comprising:

[0106] A torque determination unit is configured to determine the current powertrain allowed recovery torque based on the current state of the vehicle.

[0107] An initial braking recovery torque capability calculation unit is configured to calculate the coasting energy recovery torque, and the initial braking recovery torque capability is the current powertrain allowed recovery torque minus the coasting energy recovery torque.

[0108] A correction unit is configured to correct the initial braking recovery torque capability according to the vehicle speed and the driving torque, and the corrected initial braking recovery torque capability is the upper limit value of the IBC allowed braking recovery torque.

[0109] The electric vehicle braking energy recovery capability calculation system provided by the present application first determines the current powertrain allowed recovery torque based on the current state of the vehicle, then calculates the coasting energy recovery torque, and the initial braking recovery torque capability is the current powertrain allowed recovery torque minus the coasting energy recovery torque, and then corrects the initial braking recovery torque capability according to the vehicle speed and the driving torque, and the corrected initial braking recovery torque capability is the upper limit value of the IBC allowed braking recovery torque. By calculating the available capability of the electric braking system by the PDCU for the IBC, the overcharging and overdischarging of the battery can be effectively avoided, and the vehicle driving experience is improved.

[0110] Specifically, the technical problem to be solved by the present application is that in an electric vehicle, energy recovery can increase the cruising range of the electric vehicle. Energy recovery is generally controlled by two controllers, PDCU controls coasting energy recovery, IBC controls braking energy recovery, PDCU as the brain of the whole vehicle, interacts with BMS (Battery Management System) / MCU (Motor Control Unit), and is more clear about the system capability. By calculating the available capability of the electric braking system by the PDCU for the IBC, the overcharging and overdischarging of the battery can be effectively avoided, and the vehicle driving experience is improved.

[0111] The complete technical solution of the present application is as follows:

[0112] The present application proposes a kind of electric vehicle braking energy recovery capability calculation system, see Figure 1 , comprising the following steps:

[0113] Based on the current state of the vehicle, the torque allowed to be recovered by the current powertrain is determined.The current state includes vehicle ready condition, current motor speed and corresponding recovery capability at current speed, and the capability, temperature limit, SOC limit, limit from power to torque of axle.

[0114] PDCU calculates the coasting energy recovery, and the torque allowed to be recovered by the current powertrain minus the coasting recovery calculated by PDCU is the initial braking recovery capability.

[0115] The initial braking recovery capability is corrected according to the vehicle speed and driving torque, and the corrected one is the final braking recovery capability, which is sent to IBC as the upper limit value of IBC braking energy recovery.

[0116] Based on the current state of the vehicle, the torque allowed to be recovered by the current powertrain is determined, including:

[0117] Determine whether the current vehicle is in ready state, if it is in ready state, calculate the current recoverable power of the battery according to the current charging power allowed by the battery, the charging voltage allowed, and the charging recoverable current. Determine the external characteristic parameters of the motor recovery working condition according to the current speed of the motor, and determine the maximum recoverable torque capability of the power system according to the maximum torque that the drive shaft can withstand If the vehicle is not in ready state, the power system capability is 0.

[0118] According to the battery, the current recoverable torque is calculated: when the battery SOC is high or the temperature is high, it will affect the charging power of the battery (the charging power is negative), so first limit the discharge power allowed by the battery SOC and the battery temperature, and the limited power is , the power consumed by the accessory can be part of the battery recovery capability, so the recoverable power of the power system is The recovery power of the battery is affected by the battery voltage and current, and according to the current voltage or current of the battery, the maximum recoverable power allowed by the battery is calculated , and the final recoverable power of the power system limited by the battery voltage and current is When the actual recovery power of the battery exceeds the maximum allowable recovery power of the battery, the PDCU sets the recovery power to 0 to avoid overcharging the battery.

[0119] In the pure electric system, the recovery source of the battery is the motor, so The limit of motor recovery power, based on which the torque capacity that the motor can recover according to the battery condition is calculated according to the least square method .

[0120] The final calculated torque that the current powertrain allows to recover . That is, within the capability range of the motor battery and drive shaft.

[0121] The PDCU calculates the coasting energy recovery, and the torque that the current powertrain allows to recover minus the coasting recovery calculated by the PDCU is the initial braking recovery capacity, including:

[0122] Referring to Figure 2 , the energy recovery generally includes two parts, one part is the coasting energy recovery calculated by the PDCU , and the other part is the braking energy recovery calculated by the IBC. The PDCU obtains the coasting energy recovery torque required by the driver according to the current vehicle speed, the accelerator pedal opening degree, and the recovery mode, and the initial braking recovery capacity does not include the coasting energy recovery. That is .

[0123] The initial braking recovery capacity is corrected according to the vehicle speed and the drive torque, and the corrected final braking recovery capacity is sent to the IBC as the upper limit value of the IBC braking energy recovery, including:

[0124] In the correction of the vehicle speed, the correction formula is: ;

[0125] Among them is the correction coefficient determined according to the vehicle speed and the driving mode. The value of may be determined according to the calibration condition, and the calibration value is as follows:

[0126] 0 10 20 30 40 50 60 80 100 120 140 180 Strong recovery 0 0.1 0.2 0.2 0.2 0.2 0.2 0.2 1 1 1 1 Medium recovery 0 0.1 0.2 0.2 0.2 0.2 0.2 0.2 1 1 1 1 Low recovery 0 0.1 0.2 0.2 0.2 0.2 0.2 0.2 1 1 1 1

[0127] The corrected braking recovery capacity is smaller in value than that before correction.

[0128] Referring to Figures 3-4 , in the correction of the drive torque, the current driving condition is determined according to the current vehicle speed, the accelerator pedal opening degree, the gear position and other information, if the current condition is in the driving state, the braking recovery capacity is decreased to 0 with a certain gradient, and if the current condition is in the recovery condition, the braking recovery capacity is increased to ,

[0129] The processing formula after increasing and decreasing is:

[0130]

[0131] Among them A positive value indicates an increment in each cycle. A negative value indicates a decrease in value for each cycle; For the final permitted regenerative braking capability sent to the IBC, This indicates the regenerative braking capability after adjustment based on the driving torque. for The difference between the current moment and the previous moment.

[0132] Drive and recovery status determination: The vehicle is in ready state, in D gear, and the driver requests torque. Greater than When in reverse (R) gear, the driver requests torque less than... When it is in the driving state, it is in the recycling state; otherwise, it is in the recycling state.

[0133] The beneficial effects of the technical solution of this invention are as follows:

[0134] By accurately calculating regenerative braking capacity, the chassis domain controller can determine the upper limit of regenerative braking energy, limiting it within the battery's regenerative capacity and effectively preventing battery overcharging, thus protecting battery life. Furthermore, by judging the driving and regenerative states, the regenerative braking capacity can be adjusted to suppress the generation of regenerative braking torque during driving conditions (e.g., dual-foot driving), avoiding a rapid torque drop due to the accumulation of regenerative braking torque, which can lead to poor driving performance and improve overall vehicle NVH (noise, vibration, and harshness).

[0135] Based on the same inventive concept, embodiments of the present invention also provide an electronic device. Figure 6 This is a structural block diagram of an electronic device provided in an embodiment of the present invention. Figure 6 As shown, an embodiment of the present invention provides an electronic device including: one or more processors 101, a memory 102, and one or more I / O interfaces 103. The memory 102 stores one or more programs, which, when executed by the one or more processors, enable the one or more processors to implement any of the electric vehicle braking energy recovery capability calculation methods described in the above embodiments; the one or more I / O interfaces 103 are connected between the processor and the memory, configured to enable information interaction between the processor and the memory.

[0136] The processor 101 is a device with data processing capability, including but not limited to a central processing unit (CPU) and the like; the memory 102 is a device with data storage capability, including but not limited to a random access memory (RAM, more specifically SDRAM, DDR, etc.), a read-only memory (ROM), an electrically erasable programmable read-only memory (EEPROM), and a flash memory (FLASH); the I / O interface (read-write interface) 103 is connected between the processor 101 and the memory 102, and can realize information interaction between the processor 101 and the memory 102, including but not limited to a data bus (Bus) and the like.

[0137] In some embodiments, the processor 101, the memory 102, and the I / O interface 103 are connected to each other through the bus 104, and further connected to other components of the computing device.

[0138] In some embodiments, the one or more processors 101 include a field programmable gate array.

[0139] The embodiments of the present application also provide a computer readable medium. The computer readable medium stores a computer program, wherein the program is executed by a processor to implement the steps in the electric vehicle braking energy recovery capability calculation method in any of the above embodiments. The computer readable storage medium can be a volatile or non-volatile computer readable storage medium.

[0140] The embodiments of the present application also provide a computer program product, including a computer readable code or a non-volatile computer readable storage medium carrying the computer readable code. When the computer readable code is run in the processor of an electronic device, the processor in the electronic device executes the electric vehicle braking energy recovery capability calculation method.

[0141] Those skilled in the art can understand that all or some of the steps in the above disclosed method, the functions of the modules / units in the system and the device can be implemented as software, firmware, hardware, and appropriate combinations thereof. In the hardware implementation, the division between the functional modules / units mentioned in the above description does not necessarily correspond to the division of physical components; for example, one physical component can have multiple functions, or one function or step can be performed by several physical components in cooperation. Some or all of the physical components can be implemented as software executed by a processor, such as a central processing unit, a digital signal processor, or a microprocessor, or as hardware, or as an integrated circuit, such as an application specific integrated circuit. Such software can be distributed on a computer readable storage medium, which can include computer storage media (or non-transitory media) and communication media (or transitory media).

[0142] As those skilled in the art will appreciate, the term computer storage media includes volatile and non-volatile, removable and non-removable media implemented in any method or technology for storage of information such as computer readable program instructions, data structures, program modules or other data. Computer storage media include, but are not limited to, random access memory (RAM), read only memory (ROM), erasable programmable read only memory (EPROM), electrically erasable programmable read only memory (EEPROM), static random access memory (SRAM), flash memory or other memory technology, portable compact disc read only memory (CD-ROM), digital versatile disk (DVD) or other optical disk storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other medium which can be used to store the desired information and which can be accessed by a computer. Further, as those skilled in the art will appreciate, communication media typically embodies computer readable program instructions, data structures, program modules or other data in a modulated data signal such as a carrier wave or other transport mechanism and includes any information delivery media. The term "modulated data signal" means a signal that has one or more of its characteristics changed or set in a manner so as to encode information in the signal. By way of example, and not limitation, communication media includes wired media such as a wired network or direct-wired connection, and wireless media such as wireless networks, cellular telephone networks, code division multiple access (CDMA) networks, and other terrestrial and satellite radio frequency communication networks. Thus the computer readable program instructions and / or other program modules can be embodied in a computer readable storage medium, which can be any device or article that is enab!ed to store and / or carry computer readable program instructions and / or data structures. The computer readable storage medium can also be distributed over networked computer systems so that the computer readable program instructions and / or other program modules are stored and executed in a distributed fashion.

[0143] Computer readable program instructions described herein can be downloaded to respective computing / processing devices from a computer readable storage medium or to an external computer or external storage device via a network, for example, the Internet, a local area network, a wide area network and / or a wireless network. The network can comprise copper transmission cables, optical transmission fibers, wireless transmission, routers, firewalls, switches, gateway computers and / or edge servers. A network adapter card or network interface in each computing / processing device receives computer readable program instructions from the network and forwards the computer readable program instructions for storage in a computer readable storage medium within the respective computing / processing device.

[0144] Computer readable program instructions for carrying out operations of the present application can be assembler instructions, instruction-set-architecture (ISA) instructions, machine instructions, machine dependent instructions, microcode, firmware instructions, state-setting data, or either source code or object code written in any combination of one or more programming languages, including an object oriented programming language such as Smalltalk, C++ or the like, and conventional procedural programming languages, such as the "C" programming language or similar programming languages. The computer readable program instructions can execute entirely on the user's computer, partly on the user's computer, as a stand-alone software package, partly on the user's computer and partly on a remote computer or entirely on the remote computer or server. In the latter scenario, the remote computer can be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or the connection can be made to an external computer (for example, through the Internet using an Internet Service Provider). In some embodiments, electronic circuitry including, for example, programmable logic circuitry, field-programmable gate array (FPGA), or programmable logic array (PLA) can execute the computer readable program instructions by utilizing state information of the computer readable program instructions to personalize the electronic circuitry, in order to perform aspects of the present application.

[0145] The computer program product described herein can be embodied in a specific manner by hardware, software, or a combination thereof. In an optional embodiment, the computer program product is embodied as a computer storage medium. In another optional embodiment, the computer program product is embodied as a software product, such as a software development kit (SDK), and the like.

[0146] The computer program product described herein can be embodied in a specific manner by hardware, software, or a combination thereof. In an optional embodiment, the computer program product is embodied as a computer storage medium. In another optional embodiment, the computer program product is embodied as a software product, such as a software development kit (SDK), and the like.

[0147] These computer readable program instructions can be provided to a processor of a general purpose computer, special purpose computer, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions / acts specified in the flowchart and / or block diagram block or blocks. These computer readable program instructions can also be stored in a computer readable storage medium that can include a non-transitory computer readable storage medium that can be a computer- readable storage medium having no data storage cycles that change state. The instructions can be executed by one or more processors of a computer, other programmable data processing apparatus, or other devices to produce a computer-implemented process such that the instructions which execute via the one or more processors of the computer or other programmable data processing devices create means for implementing the functions / acts specified in the flowchart and / or block diagram block or blocks. The computer program instructions can also be loaded onto a computer, other programmable data processing apparatus, or other devices to cause a series of operational steps to be performed on the computer, other programmable apparatus or other devices to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide processes for implementing the functions / acts specified in the flowchart and / or block diagram block or blocks.

[0148] The computer readable program instructions can also be loaded onto a computer, other programmable data processing apparatus, or other device to cause a series of operational steps to be performed on the computer, other programmable apparatus or other device to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide processes for implementing the functions / acts specified in the flowchart and / or block diagram block or blocks.

[0149] The flow diagrams and the block diagrams in the drawings are presented to illustrate the architecture, functionality, and operation of possible implementations of systems, methods and computer program products according to the present application. In this regard, each block in the flow diagrams and the block diagrams can represent a module, segment, or portion of code, which comprises one or more executable instructions for implementing the specified logical functions ("instructions"). In some alternative implementations, the functions noted in the blocks can occur out of the order noted in the figures. For example, two blocks shown in succession may, in fact, be executed substantially concurrently, or the blocks can sometimes be executed in the reverse order, depending upon the functionality involved. It will also be noted that each block of the block diagrams and / or flow diagrams, and combinations thereof, can be implemented by special purpose hardware-based systems that perform the specified functions or acts, or combinations of special purpose hardware and

[0150] Example embodiments have been disclosed herein and, although specific terms are employed, they are used in a generic and descriptive sense only and not for purposes of limitation. In some instances, it will be apparent to those skilled in the art that features, characteristics or aspects described in relation to one embodiment can be applied to other embodiments, unless otherwise clearly stated. It will also be apparent to those skilled in the art that various modifications can be made to the described embodiments without departing from the scope of the invention as defined by the appended claims.

Claims

1. A method of calculating a braking energy recovery capability of an electric vehicle, characterized by, The method comprises: determining the torque allowed to be recycled by the current powertrain based on the current state of the vehicle; calculating the coasting energy recycling torque, the initial braking recycling torque capability being the torque allowed to be recycled by the current powertrain minus the coasting energy recycling torque; correcting the initial braking recycling torque capability according to the vehicle speed and the driving torque, the corrected initial braking recycling torque capability being the upper limit of the braking recycling torque allowed by the IBC.

2. The method of claim 1, wherein, The determination of the torque allowed to be recycled by the current powertrain based on the current state of the vehicle comprises: determining whether the current vehicle has been in a ready state; if the current vehicle has been in a ready state, calculating the current recyclable power of the battery according to the current charging allowed power, the charging allowed voltage and the charging allowed recycling current of the battery, and calculating the recyclable torque of the battery according to the current recyclable power of the battery; According to the current rotating speed of the motor, the external characteristic parameters of the motor recovery working condition are determined, and according to the maximum torque that the driving shaft can bear, the maximum recoverable torque of the power system is determined ; determining the torque allowed to be recycled by the current powertrain according to the maximum recyclable torque of the power system and the recyclable torque of the battery.

3. The method of claim 2, wherein, The calculation of the current recyclable power of the battery according to the current charging allowed power, the charging allowed voltage and the charging allowed recycling current of the battery comprises: determining the power recoverable by the powertrain as a function of the battery SOC, the battery temperature and the power allowed by the battery temperature limit and the power consumed by the accessories ;​ According to the current voltage or current of the battery, the maximum recoverable power currently allowed by the battery is calculated The final recoverable power of the power system under the limitation of the battery voltage and current is ​ When the actual recovered power of the battery exceeds the maximum allowed recovered power of the battery, the recovered power is set to 0.

4. The method of claim 3, wherein, in a pure electric system, the recycling source of the battery is the motor, and the calculation of the recyclable torque of the battery according to the current recyclable power of the battery comprises: According to the recovered power , and the battery recoverable torque of the current motor is calculated by least square method .

5. The method of claim 1, wherein, The calculation of the coasting energy recycling torque comprises: the PDCU obtains the coasting energy recycling torque required by the driver according to the current vehicle speed, the accelerator pedal opening degree and the recycling mode.

6. The method of claim 1, wherein, The correction of the initial braking recycling torque capability according to the vehicle speed and the driving torque comprises: In the correction of vehicle speed, the correction formula is: ; wherein is a correction coefficient determined according to vehicle speed and driving mode; In the correction of driving torque, the current driving condition is determined according to the current vehicle speed, the accelerator pedal opening degree and the gear information, if the current condition is in the driving state, the brake recovery torque capacity is decreased to 0 with a certain gradient, if the current condition is in the recovery state, the current value of the brake recovery torque capacity is increased to .

7. The method of claim 6, wherein, The determination of the current driving condition according to the current vehicle speed, the accelerator pedal opening degree and the gear information comprises: the vehicle is in a ready state; D range, driver requested torque greater than When the driver requested torque is greater than the output torque threshold, the driving condition is a drive condition, the minimum output torque in the D range; or when the driver requested torque is less than the output torque threshold, When the driver requested torque is greater than the output torque threshold, the driving condition is a drive condition, the maximum output torque in the R range; D, driver requested torque less than When the driver requested torque is less than When the driver requested torque is greater than 8. An electric vehicle brake energy recovery capability calculation system characterized by comprising: The method comprises: a torque determination unit configured to determine the torque allowed to be recycled by the current powertrain based on the current state of the vehicle; an initial braking recycling torque capability calculation unit configured to calculate the coasting energy recycling torque, the initial braking recycling torque capability being the torque allowed to be recycled by the current powertrain minus the coasting energy recycling torque; a correction unit configured to correct the initial braking recycling torque capability according to the vehicle speed and the driving torque, the corrected initial braking recycling torque capability being the upper limit of the braking recycling torque allowed by the IBC.

9. An electronic device, comprising: The method comprises: one or more processors; a memory configured to store one or more programs; when the one or more programs are executed by the one or more processors, the one or more processors are caused to implement the method according to any one of claims 1 to 7.

10. A computer readable medium having stored thereon a computer program, characterized in that The computer program is executed by the processor to implement the steps in the method according to any one of claims 1 to 7.

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