Hybrid vehicle driving behavior evaluation method and system and computer equipment

Abstract

The invention provides a hybrid vehicle driving behavior evaluation method and system and computer equipment, and relates to the field of vehicle performance evaluation. The method comprises the following steps: acquiring vehicle driving data and engine vibration data; calculating an output parameter of the driving motor, and correcting a kinetic parameter in the vehicle driving data to obtain a corrected kinetic parameter without the influence of the motor; meanwhile, vibration characteristic parameters representing the mechanical load of the engine are extracted; and comprehensively evaluating the driving behavior by combining a preset threshold value based on the corrected kinetic parameters and the vibration characteristic parameters. The method can solve the technical problem that the real operation intense degree of the engine cannot be accurately evaluated due to the fact that the interference of motor driving in the hybrid electric vehicle on the dynamics of the whole vehicle cannot be stripped and the mechanical vibration of the engine cannot be considered in the prior art.

Description

Technical Field

[0001] This invention relates to the field of vehicle performance evaluation technology, specifically to a method, system, and computer device for evaluating the driving behavior of hybrid vehicles. Background Technology

[0002] With increasing global emphasis on environmental protection, vehicle emission regulations in various countries are becoming increasingly stringent. my country's GB18352.6-2016 standard, "Limits and Measurement Methods for Pollutant Emissions from Light-Duty Vehicles (China VI)," explicitly introduces Real-World Emissions (RDE) testing as an important supplement to laboratory testing, used to assess the emission levels of vehicles under real-world road conditions.

[0003] In RDE (Real-Driving Exertion) tests, driver behavior has a significant impact on emissions results. To ensure the validity of the tests, current standards typically use stroke dynamics parameters for verification, primarily including two core indicators: the 95th percentile of the product of vehicle speed and acceleration, which characterizes the upper limit of driving intensity; and relative positive acceleration, which characterizes the lower limit of power load during driving. For traditional pure internal combustion engine vehicles, these two parameters directly reflect the engine load status and can be effectively correlated with emissions levels.

[0004] However, with the development of hybrid technology, existing evaluation methods based on vehicle dynamics have revealed significant limitations when applied to hybrid electric vehicles (HEVs / PHEVs). Hybrid electric vehicles have two power sources: an engine and a drive motor. Their overall driving state (vehicle speed, acceleration) is the result of the combined effect of both. In actual driving, the vehicle may exhibit high acceleration, but this power may primarily be provided by the rapidly responding drive motor, while the engine may be under low load or even shut down. Existing technologies directly use vehicle dynamics parameters for evaluation, failing to eliminate the power contribution of the drive motor. This leads to the misinterpretation of the motor's high power output as intense engine operation, thus failing to accurately reflect the engine's operating conditions directly related to emissions.

[0005] Furthermore, existing RDE (Reactive Engine Optimization) evaluation systems only focus on vehicle kinematic parameters (speed, acceleration), making them a "black box" external evaluation that lacks monitoring of the engine's mechanical operating status. Under certain operating conditions (such as low-speed high torque, cylinder misfire, or mechanical failure), although the engine outputs only a small vehicle acceleration, its internal structure may experience severe mechanical vibrations. This implicit, intense operation can also lead to worsened emissions. Therefore, developing a multi-dimensional collaborative driving behavior evaluation mechanism that combines dynamics and vibration is a pressing technical problem that needs to be solved in this field. Summary of the Invention

[0006] To address the shortcomings of existing technologies, this invention proposes a method, system, and computer device for evaluating the driving behavior of hybrid vehicles, in order to solve the technical problem that existing technologies cannot accurately evaluate the actual intensity of the operation of hybrid vehicle engines.

[0007] The technical solution adopted in this invention is a method for evaluating the driving behavior of hybrid vehicles, comprising: Acquire vehicle driving data and engine vibration data of hybrid electric vehicles during operation; Calculate the output parameters of the drive motor based on the vehicle driving data; Based on the output parameters, the dynamic parameters in the vehicle driving data are corrected to obtain the corrected dynamic parameters characterizing the engine operating state. Feature extraction is performed on the engine vibration data to obtain vibration characteristic parameters that characterize the mechanical load intensity of the engine; The intensity of driving behavior of hybrid electric vehicles is evaluated based on the modified dynamic parameters and the vibration characteristic parameters.

[0008] Furthermore, the dynamic parameters in the vehicle driving data are corrected based on the output parameters, including: The vehicle driving data includes vehicle speed, instantaneous acceleration, power battery voltage, power battery current, and vehicle mass; The output parameters include the drive motor power and the drive motor driving force; The modified kinetic parameters include a modified upper limit parameter and / or a modified lower limit parameter; The steps for obtaining the modified upper limit parameter include: The corrected specific power is calculated at each sampling time using the following formula: in, Indicates corrected specific power. M represents the instantaneous acceleration of the vehicle, and M represents the total mass of the vehicle. Indicates the power of the drive motor; Filter out all data points where the corrected specific power is positive, and calculate their statistical characteristic values ​​as the upper limit parameter of the correction. And / or, the step of obtaining the modified lower limit parameter includes: The corrected acceleration at each time point is calculated using the following formula: in, Indicates corrected acceleration. M represents the instantaneous acceleration of the vehicle, and M represents the total mass of the vehicle. Drive motor driving force; All data points with positive corrected acceleration are selected, and their arithmetic mean is calculated as the lower limit parameter for correction.

[0009] Furthermore, feature extraction is performed on the engine vibration data to obtain vibration characteristic parameters characterizing the engine's mechanical load intensity, including: Calculate the composite effective value of the three-dimensional vibration acceleration at each sampling time; Based on the acceleration components along the X, Y, and Z axes of the engine vibration acceleration, the composite effective value of the three-dimensional vibration acceleration at each sampling moment is calculated using the following formula: in, This represents the composite effective value of three-dimensional vibration acceleration. This represents the acceleration component along the X-axis. This represents the acceleration component along the Y-axis. Represents the acceleration component along the Z-axis; Calculate its statistical characteristic values ​​as vibration characteristic parameters.

[0010] Furthermore, the statistical characteristic value is the 90th percentile of the synthesized effective value of the three-dimensional vibration acceleration.

[0011] Furthermore, based on the corrected dynamic parameters and the vibration characteristic parameters, the intensity of driving behavior of the hybrid vehicle is evaluated, including: The intensity of driving behavior in the dynamic dimension is evaluated based on the modified dynamic parameters. The intensity of driving behavior in the vibration dimension is evaluated based on the vibration characteristic parameters. Since both the intensity of the dynamic dimension and the intensity of the vibration dimension meet the requirement of being smooth, the overall evaluation of the driving behavior is determined to be smooth. If either the intensity of the dynamic dimension or the intensity of the vibration dimension fails to meet the smoothness requirement, the overall evaluation of the driving behavior is determined to be intense.

[0012] Furthermore, the intensity of driving behavior in the dynamic dimension is evaluated based on the modified dynamic parameters, including: Obtain the vehicle's average speed during the evaluation period; Based on the average vehicle speed and the preset emission regulation verification curve, determine the upper dynamic threshold and the lower dynamic threshold. If the upper limit parameter of the correction is less than or equal to the upper limit threshold of the dynamics, and the lower limit parameter of the correction is greater than or equal to the lower limit threshold, then the driving behavior is determined to meet the smoothness requirement in the dynamics dimension. If the upper limit parameter of the correction is greater than the upper limit threshold of the dynamics, and the lower limit parameter of the correction is less than the lower limit threshold, then it is determined that the driving behavior does not meet the smoothness requirement in the dynamics dimension.

[0013] Furthermore, the intensity of driving behavior in the vibration dimension is evaluated based on the vibration characteristic parameters, including: If the vibration characteristic parameter is less than or equal to the vibration threshold, then the driving behavior in the vibration dimension is determined to meet the smoothness requirement. If the vibration characteristic parameter is greater than the vibration threshold, the driving behavior in the vibration dimension is determined to be non-compliant with the smoothness requirement.

[0014] Furthermore, the vibration threshold is calibrated based on the vibration statistics of similar engines during smooth operation.

[0015] In conjunction with the first feasible approach, a second feasible approach provides a hybrid vehicle driving behavior assessment system, comprising: The data acquisition module is used to acquire vehicle driving data and engine vibration data of the hybrid vehicle during driving. The motor parameter calculation module is used to calculate the output parameters of the drive motor based on the vehicle driving data. An engine dynamics parameter evaluation module is used to correct the dynamic parameters in the vehicle driving data based on the output parameters to obtain corrected dynamic parameters characterizing the engine operating state. The vibration feature extraction module is used to extract features from the engine vibration data to obtain vibration feature parameters that characterize the mechanical load intensity of the engine. The driving behavior judgment module is used to evaluate the intensity of driving behavior of the hybrid vehicle based on the corrected dynamic parameters and the vibration characteristic parameters.

[0016] In conjunction with the first possible implementation, a third possible implementation provides a computer device including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the method described in the first possible implementation.

[0017] As can be seen from the above technical solution, the beneficial technical effects of the present invention are as follows: 1. By calculating the power and driving force of the drive motor and subtracting them from the dynamic formula, the corrected parameters can eliminate the masking effect of the electrified drive system, truly reflect the fuel consumption load and emission intensity of the engine body, and improve the pertinence and accuracy of dynamic verification in RDE test.

[0018] 2. By introducing engine vibration characteristic parameters, it is possible to capture the hidden and intense operating conditions where the vehicle acceleration is small but the engine mechanical load is extremely high, filling the gap in the existing technology for evaluating the smoothness of mechanical operation.

[0019] 3. A collaborative verification logic is employed, ensuring that the driving is considered smooth only when both the corrected dynamic and vibration indices simultaneously meet the smoothness requirement. This evaluation mechanism effectively reduces the risk of misjudgment that may arise from relying on a single dimension, thereby improving the confidence level of the driving behavior evaluation results. Attached Figure Description

[0020] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the accompanying drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. In all the drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, the elements or parts are not necessarily drawn to scale.

[0021] Figure 1 This is a flowchart of the method in Embodiment 1 of the present invention; Figure 2 This is a system structure diagram of Embodiment 2 of the present invention; Figure label: 21-A hybrid vehicle driving behavior assessment system; 22-Data acquisition module; 23-Motor parameter calculation module; 24-Engine dynamics parameter assessment module; 25-Vibration feature extraction module; 26-Driving behavior judgment module. Detailed Implementation

[0022] The embodiments of the technical solution of the present invention will now be described in detail with reference to the accompanying drawings. These embodiments are merely illustrative of the technical solution of the present invention and are therefore intended to limit the scope of protection of the present invention.

[0023] It should be noted that, unless otherwise stated, the technical or scientific terms used in this application should have the ordinary meaning as understood by one of ordinary skill in the art to which this invention pertains.

[0024] Example 1 This embodiment provides a method for evaluating the driving behavior of hybrid vehicles. The working principle of Embodiment 1 is explained in detail below: The method flowchart of this embodiment is as follows: Figure 1 As shown, it includes: Acquire vehicle driving data and engine vibration data of hybrid electric vehicles during operation; The vehicle driving data includes vehicle speed, instantaneous acceleration, power battery voltage, power battery current, and vehicle mass; Calculate the output parameters of the drive motor based on the vehicle driving data; The output parameters include the drive motor power and the drive motor driving force; Based on the output parameters, the dynamic parameters in the vehicle driving data are corrected to obtain the corrected dynamic parameters characterizing the engine operating state. Feature extraction is performed on the engine vibration data to obtain vibration characteristic parameters that characterize the mechanical load intensity of the engine; Based on the corrected dynamic parameters and the vibration characteristic parameters, combined with preset dynamic thresholds and vibration thresholds, the intensity of driving behavior of hybrid vehicles is comprehensively evaluated.

[0025] In this embodiment, the vehicle driving data and engine vibration data of the hybrid vehicle during driving are further acquired. The vehicle driving data is mainly acquired through the vehicle CAN bus or OBD interface, and the engine vibration data is acquired through vibration sensors installed in the engine block or key locations. The data is preferably high-frequency sampled acceleration signals.

[0026] In this embodiment, further, since the power of the hybrid vehicle is provided by both the engine and the motor, in order to evaluate the actual operating conditions of the engine, it is necessary to first calculate the contribution of the motor. The output parameters of the motor include the power of the drive motor and the driving force of the drive motor.

[0027] The formula for calculating the power of the drive motor is: in, Indicates the power of the drive motor. and These represent voltage and current, respectively.

[0028] The formula for calculating the driving force of the drive motor is: in, Indicates the driving force of the drive motor. This indicates the vehicle speed. When the vehicle speed is 0, the driving force of the drive motor is obtained by converting the motor torque.

[0029] In this embodiment, the dynamic parameters in the vehicle driving data are further corrected based on the output parameters to obtain corrected dynamic parameters characterizing the engine operating state. This step aims to isolate the influence of the motor on the overall vehicle dynamics. The corrected dynamic parameters include upper limit parameters (corresponding to high load conditions) and lower limit parameters (corresponding to low load or power reserve conditions).

[0030] The steps for obtaining the modified upper limit parameter include: The corrected specific power is calculated at each sampling time using the following formula: in, Indicates corrected specific power. M represents the instantaneous acceleration of the vehicle, and M represents the total mass of the vehicle. This represents the power of the drive motor. The physical meaning of this formula is to subtract the specific power contribution of the motor from the specific power of the entire vehicle, thereby obtaining the specific power provided only by the engine.

[0031] All data points with positive corrected specific power are selected, and their statistical characteristic value (95th percentile value) is calculated as the upper limit parameter of the correction. The steps for obtaining the modified lower limit parameter include: The corrected acceleration at each time point is calculated using the following formula: in, Indicates corrected acceleration. M represents the instantaneous acceleration of the vehicle, and M represents the total mass of the vehicle. The driving force of the drive motor. This formula subtracts the acceleration generated by the motor from the total vehicle acceleration to obtain the acceleration generated by the engine.

[0032] All data points with positive corrected acceleration are selected, and their arithmetic mean is calculated as the lower limit parameter for correction.

[0033] In this embodiment, furthermore, in order to capture the mechanical intensity of the engine under low-speed, high-torque or abnormal operating conditions, this embodiment introduces a vibration dimension to extract features from the engine vibration data, obtaining vibration characteristic parameters characterizing the mechanical load intensity of the engine, including: Calculate the composite effective value of the three-dimensional vibration acceleration at each sampling time; Based on the acceleration components along the X, Y, and Z axes of the engine vibration acceleration, the composite effective value of the three-dimensional vibration acceleration at each sampling moment is calculated using the following formula: in, This represents the composite effective value of three-dimensional vibration acceleration. This represents the acceleration component along the X-axis. This represents the acceleration component along the Y-axis. Represents the acceleration component along the Z-axis; The composite effective value of the three-dimensional vibration acceleration under engine operating conditions (such as speed higher than the idle speed threshold) is selected, and its statistical characteristic value is calculated as a vibration characteristic parameter. The statistical characteristic value is the 90th percentile value of the composite effective value of the three-dimensional vibration acceleration.

[0034] In this embodiment, further, based on the modified dynamic parameters and the vibration characteristic parameters, the intensity of the driving behavior of the hybrid vehicle is evaluated, including: The intensity of driving behavior in the dynamic dimension is evaluated based on the modified dynamic parameters. The intensity of driving behavior in the vibration dimension is evaluated based on the vibration characteristic parameters. Since both the intensity of the dynamic dimension and the intensity of the vibration dimension meet the requirement of being smooth, the overall evaluation of the driving behavior is determined to be smooth. If either the intensity of the dynamic dimension or the intensity of the vibration dimension fails to meet the smoothness requirement, the overall evaluation of the driving behavior is determined to be intense.

[0035] The intensity of driving behavior in the dynamic dimension is evaluated based on the modified dynamic parameters, including: Obtain the vehicle's average speed during the evaluation period; Based on the average vehicle speed and the preset emission regulation verification curve, determine the upper dynamic threshold and the lower dynamic threshold. If the upper limit parameter of the correction is less than or equal to the upper limit threshold of the dynamics, and the lower limit parameter of the correction is greater than or equal to the lower limit threshold, then the driving behavior is determined to meet the smoothness requirement in the dynamics dimension. If the upper limit parameter of the correction is greater than the upper limit threshold of the dynamics, and the lower limit parameter of the correction is less than the lower limit threshold, then it is determined that the driving behavior does not meet the smoothness requirement in the dynamics dimension.

[0036] The intensity of driving behavior in the vibration dimension is evaluated based on the vibration characteristic parameters, including: If the vibration characteristic parameter is less than or equal to the vibration threshold, then the driving behavior in the vibration dimension is determined to meet the smoothness requirement. If the vibration characteristic parameter is greater than the vibration threshold, the driving behavior in the vibration dimension is determined to be non-compliant with the smoothness requirement.

[0037] By employing a collaborative verification logic, a driving condition is determined to be smooth only when both the corrected dynamic and vibration indices simultaneously meet the smoothness requirement. This evaluation mechanism effectively reduces the risk of misjudgment that may arise from relying on a single dimension, thereby improving the confidence level of the driving behavior evaluation results.

[0038] Example 2 In conjunction with Embodiment 1, Embodiment 2 provides a hybrid vehicle driving behavior assessment system. The system structure diagram of this embodiment is as follows: Figure 2 As shown, it includes: The data acquisition module is used to acquire vehicle driving data and engine vibration data of the hybrid electric vehicle during driving. The vehicle driving data includes vehicle speed, instantaneous acceleration, power battery voltage, power battery current and vehicle mass. The motor parameter calculation module is used to calculate the output parameters of the drive motor based on the vehicle driving data. The output parameters include the drive motor power and the drive motor driving force. An engine dynamics parameter evaluation module is used to correct the dynamic parameters in the vehicle driving data based on the output parameters to obtain corrected dynamic parameters characterizing the engine operating state. The vibration feature extraction module is used to extract features from the engine vibration data to obtain vibration feature parameters that characterize the mechanical load intensity of the engine. The driving behavior judgment module is used to evaluate the intensity of driving behavior of the hybrid vehicle based on the corrected dynamic parameters and the vibration characteristic parameters.

[0039] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be covered within the scope of the claims and specification of the present invention.

Claims

1. A method for evaluating the driving behavior of a hybrid vehicle, characterized in that, include: Acquire vehicle driving data and engine vibration data of hybrid electric vehicles during operation; Calculate the output parameters of the drive motor based on the vehicle driving data; Based on the output parameters, the dynamic parameters in the vehicle driving data are corrected to obtain the corrected dynamic parameters characterizing the engine operating state. Feature extraction is performed on the engine vibration data to obtain vibration characteristic parameters that characterize the mechanical load intensity of the engine; The intensity of driving behavior of hybrid electric vehicles is evaluated based on the modified dynamic parameters and the vibration characteristic parameters.

2. The method for evaluating the driving behavior of a hybrid vehicle according to claim 1, characterized in that, Based on the output parameters, the dynamic parameters in the vehicle driving data are corrected, including: The vehicle driving data includes vehicle speed, instantaneous acceleration, power battery voltage, power battery current, and vehicle mass; The output parameters include the drive motor power and the drive motor driving force; The modified kinetic parameters include a modified upper limit parameter and / or a modified lower limit parameter; The steps for obtaining the modified upper limit parameter include: The corrected specific power is calculated at each sampling time using the following formula: in, Indicates corrected specific power. M represents the instantaneous acceleration of the vehicle, and M represents the total mass of the vehicle. Indicates the power of the drive motor; All data points with positive corrected specific power are selected, and their statistical characteristic values ​​are calculated as the upper limit parameter of the correction. And / or, the step of obtaining the modified lower limit parameter includes: The corrected acceleration at each time point is calculated using the following formula: in, Indicates corrected acceleration. M represents the instantaneous acceleration of the vehicle, and M represents the total mass of the vehicle. Drive motor driving force; All data points with positive corrected acceleration are selected, and their arithmetic mean is calculated as the lower limit parameter for correction.

3. The method for evaluating driving behavior of a hybrid vehicle according to claim 1, characterized in that, Feature extraction is performed on the engine vibration data to obtain vibration characteristic parameters characterizing the engine's mechanical load intensity, including: Calculate the composite effective value of the three-dimensional vibration acceleration at each sampling time; Based on the acceleration components along the X, Y, and Z axes of the engine vibration acceleration, the composite effective value of the three-dimensional vibration acceleration at each sampling moment is calculated using the following formula: in, This represents the composite effective value of three-dimensional vibration acceleration. This represents the acceleration component along the X-axis. This represents the acceleration component along the Y-axis. Represents the acceleration component along the Z-axis; Calculate its statistical characteristic values ​​as vibration characteristic parameters.

4. The method for evaluating driving behavior of a hybrid vehicle according to claim 3, characterized in that, The statistical characteristic value is the 90th percentile of the synthesized effective value of the three-dimensional vibration acceleration.

5. A method for evaluating the driving behavior of a hybrid vehicle according to claim 2 or 3, characterized in that, Based on the corrected dynamic parameters and the vibration characteristic parameters, the intensity of driving behavior of hybrid vehicles is evaluated, including: The intensity of driving behavior in the dynamic dimension is evaluated based on the modified dynamic parameters. The intensity of driving behavior in the vibration dimension is evaluated based on the vibration characteristic parameters. Since both the intensity of the dynamic dimension and the intensity of the vibration dimension meet the requirement of being smooth, the overall evaluation of the driving behavior is determined to be smooth. If either the intensity of the dynamic dimension or the intensity of the vibration dimension fails to meet the smoothness requirement, the overall evaluation of the driving behavior is determined to be intense.

6. The method for evaluating driving behavior of a hybrid vehicle according to claim 5, characterized in that, The intensity of driving behavior in the dynamic dimension is evaluated based on the modified dynamic parameters, including: Obtain the vehicle's average speed during the evaluation period; Based on the average vehicle speed and the preset emission regulation verification curve, determine the upper dynamic threshold and the lower dynamic threshold. If the upper limit parameter of the correction is less than or equal to the upper limit threshold of the dynamics, and the lower limit parameter of the correction is greater than or equal to the lower limit threshold, then the driving behavior is determined to meet the smoothness requirement in the dynamics dimension. If the upper limit parameter of the correction is greater than the upper limit threshold of the dynamics, and the lower limit parameter of the correction is less than the lower limit threshold, then it is determined that the driving behavior does not meet the smoothness requirement in the dynamics dimension.

7. The method for evaluating driving behavior of a hybrid vehicle according to claim 5, characterized in that, The intensity of driving behavior in the vibration dimension is evaluated based on the vibration characteristic parameters, including: If the vibration characteristic parameter is less than or equal to the vibration threshold, then the driving behavior in the vibration dimension is determined to meet the smoothness requirement. If the vibration characteristic parameter is greater than the vibration threshold, the driving behavior in the vibration dimension is determined to be non-compliant with the smoothness requirement.

8. The method for evaluating driving behavior of a hybrid vehicle according to claim 7, characterized in that, The vibration threshold is calibrated based on the vibration statistics of similar engines during smooth operation.

9. A hybrid vehicle driving behavior assessment system, characterized in that, include: The data acquisition module is used to acquire vehicle driving data and engine vibration data of the hybrid vehicle during driving. The motor parameter calculation module is used to calculate the output parameters of the drive motor based on the vehicle driving data. An engine dynamics parameter evaluation module is used to correct the dynamic parameters in the vehicle driving data based on the output parameters to obtain corrected dynamic parameters characterizing the engine operating state. The vibration feature extraction module is used to extract features from the engine vibration data to obtain vibration feature parameters that characterize the mechanical load intensity of the engine. The driving behavior judgment module is used to evaluate the intensity of driving behavior of the hybrid vehicle based on the corrected dynamic parameters and the vibration characteristic parameters.

10. A computer device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the processor executes the computer program, it implements the method described in claims 1-8.

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