An odb remote emission monitoring data correction method and correction system

Abstract

This invention discloses a method and system for correcting OBD remote emission monitoring data. The method includes: obtaining the VSP interval based on the driving parameters corresponding to the OBD emission data in the experimental stage over time; establishing a mapping relationship between the VSP interval and PEMS emission data; calculating theoretical emission data based on the driving parameters corresponding to the OBD emission data in the actual detection stage over time and the mapping relationship; constructing confidence intervals using the theoretical emission data; and removing outliers in the OBD emission data based on the confidence intervals. The technical solution provided by this invention solves the problems of inconsistent OBD device quality, excessive data deviation, insufficient measurement accuracy, and inability to effectively monitor and control pollution source emissions.

Description

Technical Field

[0001] This invention relates to the field of environmental protection testing technology, specifically to an OBD remote emission monitoring data correction method and correction system. Background Technology

[0002] According to statistics from the Ministry of Public Security, as of June 2020, the number of motor vehicles in China reached 360 million, with 29.44 million being freight vehicles, accounting for 10.9% of the total. The increase in motor vehicle ownership means severe urban traffic pollution, with heavy-duty trucks contributing the most to mobile source pollution. Installing OBD (On-Board Diagnostics) remote online monitoring devices on heavy-duty trucks can enable real-time monitoring of various pollutant emissions. The OBD system will monitor the engine's operating status to see if the vehicle's exhaust emissions exceed standards, and will immediately issue a warning if standards are exceeded. However, currently, due to the lack of standardized manufacturing processes and the large number of manufacturers producing OBD remote online monitoring devices, the quality of OBD devices varies greatly, resulting in excessive data deviations and insufficient measurement accuracy, failing to effectively monitor and control pollution sources. Summary of the Invention

[0003] In view of this, the present invention provides an OBD remote emission monitoring data correction method and correction system, thereby overcoming the problems of excessive data deviation and insufficient measurement accuracy in OBD detection systems.

[0004] According to a first aspect, the present invention provides a method for correcting OBD remote emission monitoring data, the method comprising:

[0005] The VSP range is obtained based on the driving parameters corresponding to the OBD emission data during the experimental phase over time.

[0006] Establish a mapping relationship between the VSP range and PEMS emission data;

[0007] Theoretical emission data are calculated based on the driving parameters corresponding to the actual OBD emission data over time and the mapping relationship described above.

[0008] Confidence intervals are constructed using the theoretical emission data, and outliers in the actual OBD emission data during the detection phase are removed based on the confidence intervals.

[0009] Optionally, obtaining the VSP interval based on the driving parameters corresponding to the OBD emission data during the experimental phase over time includes:

[0010] The VSP value is calculated based on the driving parameters corresponding to the OBD emission data during the experimental phase.

[0011] The VSP value is divided into VSP intervals based on driving events.

[0012] Optionally, obtaining the VSP interval based on the driving parameters corresponding to the OBD emission data during the experimental phase over time further includes:

[0013] A preliminary data quality check was performed on all OBD data from the experimental phase to determine the time error range.

[0014] The OBD emission data for the experimental phase is adjusted according to the time error range, and the VSP interval set is obtained based on the emission data after each adjustment.

[0015] Optionally, establishing the mapping relationship between the VSP interval and PEMS emission data includes:

[0016] Establish a mapping relationship between the VSP intervals in the VSP interval set and the PEMS emission data;

[0017] The optimal mapping relationship is selected, and the corresponding optimal data adjustment scheme is obtained.

[0018] Optionally, the step of calculating theoretical emission data based on the driving parameters corresponding to the actual OBD emission data in time during the testing phase and the mapping relationship includes:

[0019] The OBD emission data of the actual testing phase are adjusted according to the optimal data adjustment scheme, and the adjusted driving parameters are obtained.

[0020] Calculate the VSP value based on the adjusted driving parameters and obtain the optimal VSP range;

[0021] The theoretical emission data are obtained based on the optimal VSP interval and the optimal mapping relationship.

[0022] Optionally, the OBD remote emission monitoring data correction method provided by the present invention further includes:

[0023] Establish a second mapping relationship between the OBD emission data and the PEMS emission data during the experimental phase;

[0024] A data correction method is selected based on the actual OBD emission data during the detection phase and the confidence interval.

[0025] Optionally, the method for selecting data correction based on the actual OBD emission data during the detection phase and the confidence interval includes:

[0026] When the emission data of OBD emission data at a certain point in the actual detection phase is outside the confidence interval, the optimal mapping relationship is selected for adjustment.

[0027] When the emission data of OBD emission data at a certain point in the actual detection phase is within the confidence interval, the second mapping relationship is selected for adjustment.

[0028] According to a second aspect, the present invention provides an OBD remote emission monitoring data correction system, the system comprising:

[0029] The data acquisition module obtains the VSP range based on the driving parameters corresponding to the OBD emission data in time during the experimental phase.

[0030] The mapping module establishes the mapping relationship between the VSP range and the PEMS emission data;

[0031] The comparison model module calculates theoretical emission data based on the driving parameters corresponding to the actual OBD emission data in time during the detection phase and the mapping relationship.

[0032] The correction module uses the theoretical emission data to create a confidence interval and removes outliers in the OBD emission data based on the confidence interval.

[0033] Optionally, the system further includes:

[0034] The second mapping module establishes a second mapping relationship between the OBD emission data and the PEMS emission data during the experimental phase.

[0035] The pattern recognition module selects a data correction method based on the actual OBD emission data during the detection phase and the confidence interval.

[0036] According to a third aspect, the present invention provides an electronic device comprising:

[0037] A memory and a processor are communicatively connected, the memory storing computer instructions, and the processor executing the computer instructions to perform the method described in the first aspect and any optional embodiment of the first aspect.

[0038] The technical solution of this invention has the following advantages:

[0039] This invention provides a method and system for correcting OBD remote emission monitoring data. The method specifically includes: obtaining the VSP interval based on the driving parameters corresponding to the OBD emission data in the experimental phase over time; establishing a mapping relationship between the VSP interval and PEMS emission data; calculating theoretical emission data based on the driving parameters corresponding to the OBD emission data in the actual monitoring phase over time and the mapping relationship; creating a confidence interval using the theoretical emission data; and eliminating outliers in the OBD emission data based on the confidence interval. A scheme for correcting OBD monitoring data is introduced based on the known linear relationship between the VSP interval and the emission amount. By adjusting the time error range between the actual emission time and the vehicle start point, and using the PEMS experimental data as the standard value, the optimal mapping relationship is fitted to obtain the corresponding optimal data adjustment scheme. The actual monitored OBD data is adjusted using the optimal data adjustment scheme, thereby calculating the theoretical emission value based on the optimal mapping relationship, and eliminating outliers outside the confidence interval calculated from the theoretical emission value. Furthermore, for OBD emission data within the confidence interval, a second mapping relationship between OBD emission data and PEMS emission data was established to further correct OBD emission data, achieving the goal of real-time correction of abnormal OBD data, improving the accuracy of the OBD detection process, quickly locating vehicles with excessive exhaust emissions, and ensuring effective monitoring and control of pollution source emissions. Attached Figure Description

[0040] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0041] Figure 1 This is a schematic diagram illustrating the steps of an OBD monitoring data correction method according to an embodiment of the present invention;

[0042] Figure 2 This is a schematic diagram of the correction process in an OBD monitoring data correction method according to an embodiment of the present invention;

[0043] Figure 3 This is a schematic diagram of the structure of an OBD monitoring data correction system according to an embodiment of the present invention;

[0044] Figure 4 This is a schematic diagram of an electronic device structure according to an embodiment of the present invention. Detailed Implementation

[0045] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0046] The technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0047] Please see Figure 1 The present invention provides a method for correcting OBD remote emission monitoring data, which specifically includes the following steps:

[0048] Step S101: Obtain the VSP interval based on the driving parameters corresponding to the OBD emission data in the experimental phase over time. Specifically, VSP (Vehicle Specific Power) refers to the power output of the engine per ton of mass (including its own weight) moved, measured in kW / t. Initially used primarily for remote sensing of exhaust emissions, it was later discovered by domestic and international scholars to link the instantaneous driving state of a vehicle with the emission amount of exhaust pollutants. Emission model research based on VSP by domestic and international scholars mainly focuses on CO and NO. x The VSP (Vehicle Performance Spatial) is calculated based on vehicle driving parameters, including speed and GPS location changes. During the OBD emission data collection phase, these driving parameters can be directly obtained from the OBD device within the same time period. Therefore, in this embodiment, the VSP range required for data correction needs to be derived from these driving parameters.

[0049] Step S102: Establish a mapping relationship between the VSP interval and PEMS emission data. Specifically, the function of this invention is to correct the OBD emission data during the actual operation of a vehicle based on a data correction model established under experimental conditions. PEMS (Portable Emission Measurement System) provides highly accurate vehicle pollutant emission values, but due to its large size, it cannot be installed on a vehicle. Therefore, OBD is used to monitor relevant vehicle information during actual operation. In the data correction model establishment stage, PEMS emission data is used as the image, and the VSP interval from step S101 is used as the preimage to establish a mapping relationship. This embodiment of the invention uses, but is not limited to, the least squares method for curve fitting from the VSP interval to the PEMS emission data. Then, based on the mapping relationship, theoretical emission data with high accuracy can be calculated during actual monitoring, thereby correcting the actual emission data.

[0050] Step S103: Calculate theoretical emission data based on the driving parameters and mapping relationship corresponding to the OBD emission data in the actual testing phase over time. Specifically, in the actual testing phase, driving parameters are collected through the OBD device, which means obtaining the speed and GPS location corresponding to each time point during the actual driving process. The VSP interval in the actual driving process is calculated using the above driving parameters. The obtained actual VSP interval is used as the preimage of the mapping relationship in step S102, and the corresponding theoretical emission value can be calculated. Then, the data correction in step S104 is performed.

[0051] Step S104: Construct confidence intervals using theoretical emission data and eliminate outliers in the actual OBD emission data during the testing phase based on these intervals. Specifically, when the OBD emission data at a certain time point falls outside the confidence interval of the corresponding theoretical emission data, the OBD emission data is considered abnormal. There are many reasons for data anomalies, including OBD device quality issues or environmental factors that cause significant differences in OBD emission data. In this case, the VSP interval corresponding to the same driving event conditions at the corresponding time point is used as the input value for the mapping relationship to calculate the theoretical emission value at the current moment, thereby replacing the abnormal OBD emission data. The confidence interval is calculated based on the average and standard deviation of the theoretical emission data obtained at each time point. The specific calculation method for the confidence interval is as follows: calculate the average and standard deviation of the theoretical emission data at each time point, ensuring that the effective second-by-second emission rate data falls within the range of [average - 3 * standard deviation, average + 3 * standard deviation]. This achieves automatic correction of OBD emission data and improves the accuracy of the OBD detection process.

[0052] Specifically, in one embodiment, step S101 above includes the following steps:

[0053] Step S201: Calculate the VSP value based on the driving parameters corresponding to the OBD emission data during the experimental phase. Specifically, from a physical perspective, VSP comprehensively considers the components of the power output of the vehicle engine, including the increase in the vehicle's kinetic and potential energy, the work done to overcome rolling friction resistance, and the work done to overcome air resistance. The VSP variable, independent of vehicle weight, can precisely link the instantaneous operating state of the vehicle with emissions. However, using VSP values ​​to establish a mapping relationship between emissions results in significant data dispersion; therefore, smoke emissions cannot be directly evaluated using VSP variables. Establishing a VSP interval can effectively solve this problem. The VSP interval is derived from the instantaneous VSP values. The correction scheme of this embodiment mainly targets the correction of exhaust pollutants from medium and heavy-duty passenger and freight vehicles. Therefore, the VSP calculation formula for medium and heavy-duty passenger and freight vehicles is first used: Calculate the VSP value of the collected data.

[0054] Step S202: Divide the VSP values ​​into VSP intervals based on driving events. Specifically, mapping VSP intervals to PEMS emission data yields a good linear relationship compared to VSP values; therefore, this step divides the VSP values ​​to obtain VSP intervals. Based on driving parameters during vehicle operation, the vehicle is divided into multiple different driving events. Driving parameters characterize vehicle speed and GPS location changes, while driving events characterize vehicle speed. The specific division criteria are described below:

[0055] ① Transitional state: acceleration or deceleration. If the speed field is not equal to 0 and the acceleration is not equal to 0, the vehicle is considered to be in a transitional state.

[0056] ② Uniform speed: If the velocity field is not equal to 0, and the acceleration is -0.1m / s² ~0.1m / Between these points, it is assumed that the vehicle is moving at a constant speed.

[0057] ③ Idle speed: The vehicle is considered to be idling when the vehicle speed is less than or equal to 1.6 km / h and the engine speed is less than or equal to the normal warm-up idle speed of 200 r / min.

[0058] For a continuous driving process, the vehicle speed undergoes a non-continuous increase and non-continuous decrease process. The VSP values ​​under the same driving event are clustered. Based on the VSP intervals divided in the MOVES model, this embodiment divides the instantaneous VSP values ​​in each range of data into intervals of 1kW / t according to the driving event. The interval is not limited to this.

[0059] Specifically, in one embodiment, step S101 above further includes the following step:

[0060] Step S203: Perform a preliminary data quality check on all OBD data from the experimental phase to determine the time error range. Specifically, after collecting OBD emission data, to improve the accuracy and reliability of the data correction process, it is necessary to pre-check the data quality of the collected OBD data. The check includes:

[0061] The integrity of OBD monitoring data must be checked. The data used for processing cannot contain blank or negative values. Therefore, the integrity of the data must be checked second by second to verify its completeness, and to ensure that speed and emission data are not missing or negative. Missing or negative data should be marked. Such data cannot be used in subsequent emission rate calculations. According to the data statistics, each vehicle has approximately 3-30 blank or negative data points, accounting for about one-thousandth of the total data volume. Therefore, the data integrity can be judged as good, further ensuring the accuracy of subsequent calculation steps.

[0062] To align OBD monitoring data, VSP intervals, and PEMS experimental data, OBD monitoring and PEMS experiments were conducted on heavy-duty trucks. Control samples were collected within the same time period, gathering data from all fields supported for upload by OBD and PEMS experimental data. A comparison of the OBD and PEMS data was then performed. First, the two data sets needed to be aligned within the same time period; that is, using a specific time point as a reference, the two data segments were aligned according to their collection time at that point. Furthermore, VSP intervals under the same driving events were aligned with the PEMS experimental data to facilitate the establishment of subsequent mapping relationships.

[0063] Data was cleaned based on national standards, and the conventional energy consumption and emission thresholds of the study vehicles under various events were determined by comparing the data with experimental data. The following data cleaning and labeling operations were performed on the uploaded data:

[0064] ① Delete duplicate data. Duplicate data here refers to multiple records of the same vehicle at the same time.

[0065] ② Clean and filter data with empty fields such as vehicle ID, latitude and longitude, and time, and filter out records with incorrect time formats;

[0066] ③ Remove records that are not within the specified time period;

[0067] ④ It is necessary to determine the number of valid coordinates of the vehicle. Valid data points indicate that the vehicle is moving. If a vehicle has many trajectory points, but the number of completely repeated coordinate points or the number of non-repeating coordinate points is small, then the vehicle data is discarded.

[0068] ⑤ If the GPS conversion speed and the test data speed are inconsistent, perform data correction.

[0069] ⑥ Eliminate abnormal accelerations.

[0070] The cleanup was carried out according to the OBD threshold in the Emission Limits and Measurement Methods for Heavy-Duty Diesel Vehicles (China VI), as follows:

[0071]

[0072] By performing preliminary cleaning of abnormal data in OBD, invalid data is prevented from entering the calculation stage of the correction method, further improving the overall accuracy of the correction system.

[0073] Finally, the starting point of the heavy-duty truck (the point where speed accelerates from 0) and the point where NOx emissions are generated are checked to determine if they are at the same time point, thus initially determining the time matching error. Based on data processing experience, when a vehicle starts, the starting point and the emission data generation point are often not at the same time point, resulting in a certain time misalignment. The time matching between speed records and emission records is not perfect. Therefore, the optimal confidence interval is also based on the calculation of the time error range, and accurate estimation of the time error range ensures the accuracy of the overall correction method.

[0074] Step S204: Adjust the OBD emission data during the experimental phase according to the time error range, and obtain a VSP interval set based on the adjusted emission data. Specifically, since the vehicle's start point and the emission data generation point are often not at the same time point, multiple data segments are obtained by adjusting the time error range. A mapping relationship can be established for each VSP interval obtained from each data segment, which lays the foundation for obtaining the most reliable mapping relationship later. By using multiple data as a basis, the optimal data is selected, improving the accuracy of subsequent theoretical emission data. In this embodiment, this range is set to 20 seconds before and after the original matching time [-20, +20] based on actual operating experience. Within this range, the data segments are adjusted second by second to avoid the problem of unreliable single data. For example: OBD data is collected 1 second at a time, packaged and uploaded every 30 seconds, with a time error range of 3 seconds. The time periods after collection and adjustment are data from 1 to 30 seconds, data from 2 to 31 seconds, and data from 3 to 32 seconds. Then, the VSP intervals obtained from different time periods are stored in a set for use in subsequent steps.

[0075] Specifically, in one embodiment, step S102 above includes the following steps:

[0076] Step S205: Establish mapping relationships between VSP intervals and PEMS emission data based on the VSP interval set. Specifically, in one embodiment, the average value of the instantaneous PEMS emission data corresponding to all VSP values ​​in the VSP interval is taken as the image of the mapping relationship. The VSP interval is used as the preimage, and curve fitting is performed using the least squares method to obtain the mapping relationship between the VSP interval and the PEMS emission data. For example, when data at a certain point is collected, the VSP value of that point can be calculated using the driving parameters of that point. By determining the VSP interval in which the VSP value belongs, the corresponding theoretical emission data can be obtained through the mapping relationship.

[0077] Step S206: Select the optimal mapping relationship and obtain the corresponding optimal data adjustment scheme. Specifically, data from different time periods can obtain different mapping relationships according to the steps in S205. To improve the accuracy of the correction method, we need to select the optimal mapping relationship. The method for selecting the optimal mapping relationship includes, but is not limited to, the correlation coefficient method. This embodiment of the invention adopts... To determine the goodness of fit of the fitted curve, the time error was adjusted and the correlation coefficient between the emission data and VSP (greater than 0) was calculated. The specific results are as follows:

[0078]

[0079] The higher the correlation coefficient, the better the curve fits. Then, the correlation coefficient... The largest mapping relationship is selected as the optimal mapping relationship. The time adjustment scheme corresponding to the optimal mapping relationship is the optimal data adjustment scheme.

[0080] Specifically, in one embodiment, step S103 above includes the following steps:

[0081] Step S207: Adjust the OBD emission data during the actual testing phase according to the optimal data adjustment scheme, and obtain the adjusted driving parameters. Specifically, during the actual driving process of the vehicle, the actual testing phase cannot obtain relatively accurate emission monitoring data from the PEMS device for comparison. Therefore, it is necessary to use the mapping relationship established in the above steps to obtain more accurate theoretical emission data. The optimal data adjustment scheme obtained in the above steps refers to adjusting the specific time interval of the data. For example, if the data segment interval collected by the OBD device is 30 seconds, and initially data from 1 to 30 seconds is used, the optimal data adjustment scheme is to adjust it by 1 second. Therefore, we will change it to data from 2 to 31 seconds for the next steps. The data adjusted according to time includes emission data and the driving parameters corresponding to the emission data at each time point.

[0082] Step S208: Calculate the VSP value and obtain the optimal VSP range based on the adjusted driving parameters. Specifically, obtain the driving parameters corresponding to the adjusted data segment through the OBD device, and then use the formula... Calculate the VSP value corresponding to the driving parameters at each time point, and then divide the VSP value into VSP intervals according to the criteria for dividing driving events in step S202. The VSP intervals obtained here are the VSP intervals of the optimal solution.

[0083] Step S209: Obtain theoretical emission data based on the optimal VSP interval and the optimal mapping relationship. Specifically, using the optimal VSP interval obtained in step S208 as the preimage of the optimal mapping relationship, the corresponding theoretical emission data is obtained as the image of the mapping relationship. Through the data alignment, data cleaning, optimization of the time adjustment scheme, and optimization of the mapping relationship in the above steps, the obtained theoretical emission data has higher accuracy, improving the accuracy and reliability of the OBD emission data correction method of the present invention.

[0084] Specifically, in one embodiment, the OBD remote emission monitoring data correction method provided by the present invention further includes the following steps:

[0085] Step S210: Establish a second mapping relationship between OBD emission data and PEMS emission data during the experimental phase. Specifically, as follows... Figure 2 As shown, to further improve the accuracy of the correction method of this invention, an optimization scheme based on the above steps is proposed. When the monitored OBD data does not exceed the confidence interval, in order to further optimize the data, in the data modeling of the experimental stage, in addition to mapping the VSP interval and PEMS, a second mapping relationship is also established between the OBD emission data adjusted according to the optimal data adjustment scheme and the PEMS emission data. The adjusted OBD emission data is used as the preimage, and the PEMS emission data is used as the image. The embodiments of this invention use, but are not limited to, the least squares method to fit the fitting curves of the OBD emission data and the PEMS emission data. In the actual detection stage, when the OBD emission data at a certain time point does not exceed the confidence interval, the OBD emission data at that point is adjusted according to the second mapping relationship, and the OBD emission data at that point is used as the output value replaced by the second mapping relationship.

[0086] Step S211: Select a data correction method based on the actual OBD emission data and confidence interval during the testing phase. Specifically, for adjusted OBD emission data, the adjustment status of the data at a certain time point is determined by whether the data falls within the confidence interval of the theoretical emission data at that time point.

[0087] Specifically, in one embodiment, step S211 above includes the following steps:

[0088] Step S212: When the emission data at a certain time point in the actual OBD emission data detection phase is outside the confidence interval, the optimal mapping relationship is selected for adjustment. Specifically, the theoretical emission data is calculated by inputting the optimal mapping relationship into the VSP interval corresponding to that time point. The OBD emission data at that time point is replaced by the theoretical emission data.

[0089] Step S213: When the emission data at a certain time point of the OBD emission data in the actual detection phase is within the confidence interval, the second mapping relationship is selected for adjustment. Specifically, the OBD emission data at that time point is input into the second mapping relationship to calculate the output value. The OBD emission data at that time point is replaced by this output value. Through the above steps S210~S213, by fine-tuning non-abnormal data, the adjustment method of the OBD data correction method of the present invention is further optimized, and the accuracy and reliability of the method are improved.

[0090] By performing the above steps, this invention provides a method for correcting OBD remote emission monitoring data. Based on the known linear relationship between the VSP interval and emissions, an OBD monitoring data correction scheme is introduced. According to the time error range between the actual emission time and the vehicle start point, using PEMS experimental data as the standard value, the optimal mapping relationship is fitted to obtain the corresponding optimal data adjustment scheme. The actual monitored OBD data is adjusted using the optimal data adjustment scheme, and the theoretical emission value is calculated based on the optimal mapping relationship. Outliers outside the confidence interval calculated from the theoretical emission value are then eliminated. Furthermore, for OBD emission data within the confidence interval, a second mapping relationship between OBD emission data and PEMS emission data is established to further correct the OBD emission data. This achieves the goal of real-time correction of abnormal OBD data, improves the accuracy of the OBD detection process, quickly locates vehicles with excessive exhaust emissions, and ensures effective monitoring and control of pollution source emissions.

[0091] like Figure 3 As shown, this embodiment also provides an OBD remote emission monitoring data correction system, which includes:

[0092] The data acquisition module 101 obtains the VSP interval based on the driving parameters corresponding to the OBD emission data over time during the experimental phase. For details, please refer to the relevant description of step S101 in the above method embodiment, which will not be repeated here.

[0093] Mapping module 102 establishes the mapping relationship between VSP intervals and PEMS emission data. For details, please refer to the relevant description of step S102 in the above method embodiment, which will not be repeated here.

[0094] The comparison model module 103 calculates theoretical emission data based on the driving parameters and mapping relationships corresponding to the actual OBD emission data over time. For details, please refer to the relevant description of step S103 in the above method embodiment; it will not be repeated here.

[0095] The correction module 104 uses theoretical emission data to create confidence intervals and then removes outliers from the OBD emission data based on these intervals. For details, please refer to the description of step S104 in the above method embodiment; it will not be repeated here.

[0096] Specifically, in one embodiment, the system further includes:

[0097] The second mapping module 210 establishes a second mapping relationship between OBD emission data and PEMS emission data during the experimental phase. For details, please refer to the relevant description of step S210 in the above method embodiment, which will not be repeated here.

[0098] The pattern recognition module 211 selects a data correction method based on the actual OBD emission data and confidence interval during the detection phase. For details, please refer to the relevant description of step S211 in the above method embodiment, which will not be repeated here.

[0099] The OBD monitoring data correction system provided in this embodiment of the invention is used to execute the OBD monitoring data correction method provided in the above embodiment. Its implementation method and principle are the same. For details, please refer to the relevant description of the above method embodiment, which will not be repeated here.

[0100] Through the collaborative efforts of the aforementioned components, this invention provides an OBD remote emission monitoring data correction system. Based on the known linear relationship between the VSP interval and emissions, an OBD monitoring data correction scheme is introduced. According to the time error range between the actual emission time and the vehicle start point, using PEMS experimental data as the standard value, an optimal mapping relationship is fitted to obtain the corresponding optimal data adjustment scheme. The actual monitored OBD data is adjusted using the optimal data adjustment scheme, and then the theoretical emission value is calculated based on the optimal mapping relationship. Outliers outside the confidence interval calculated from the theoretical emission value are eliminated. Furthermore, for OBD emission data within the confidence interval, a second mapping relationship between OBD emission data and PEMS emission data is established to further correct the OBD emission data. This achieves the goal of real-time correction of abnormal OBD data, improves the accuracy of the OBD detection process, quickly locates vehicles with excessive exhaust emissions, and ensures effective monitoring and control of pollution source emissions.

[0101] Figure 4 An electronic device according to an embodiment of the present invention is shown. The device includes a processor 901 and a memory 902, which can be connected via a bus or other means. Figure 4Taking the example of a connection between China and Israel via a bus.

[0102] Processor 901 can be a central processing unit (CPU). Processor 901 can also be other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, or combinations of the above types of chips.

[0103] The memory 902, as a non-transitory computer-readable storage medium, can be used to store non-transitory software programs, non-transitory computer-executable programs, and modules, such as the program instructions / modules corresponding to the methods in the above method embodiments. The processor 901 executes various functional applications and data processing of the processor by running the non-transitory software programs, instructions, and modules stored in the memory 902, thereby implementing the methods in the above method embodiments.

[0104] The memory 902 may include a program storage area and a data storage area. The program storage area may store the operating system and applications required for at least one function; the data storage area may store data created by the processor 901, etc. Furthermore, the memory 902 may include high-speed random access memory and may also include non-transitory memory, such as at least one disk storage device, flash memory device, or other non-transitory solid-state storage device. In some embodiments, the memory 902 may optionally include memory remotely located relative to the processor 901, and these remote memories may be connected to the processor 901 via a network. Examples of such networks include, but are not limited to, the Internet, corporate intranets, local area networks, mobile communication networks, and combinations thereof.

[0105] One or more modules are stored in memory 902 and, when executed by processor 901, perform the methods described in the above method embodiments.

[0106] The specific details of the aforementioned electronic device can be understood by referring to the relevant descriptions and effects in the above method embodiments, and will not be repeated here.

[0107] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The implemented program can be stored in a computer-readable storage medium. When the program is executed, it can include the processes of the embodiments of the methods described above. The storage medium can be a magnetic disk, optical disk, read-only memory (ROM), random access memory (RAM), flash memory, hard disk drive (HDD), or solid-state drive (SSD), etc.; the storage medium can also include combinations of the above types of memory.

[0108] Although embodiments of the invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A method for correcting OBD remote emission monitoring data, characterized in that, The method includes: The VSP interval is obtained by corresponding driving parameters to the OBD emission data in the experimental phase over time; the time error range is obtained by performing a preliminary data quality check on all OBD data in the experimental phase; the OBD emission data in the experimental phase is adjusted according to the time error range, and the VSP interval set is obtained based on the emission data after each adjustment. Establish a mapping relationship between the VSP intervals and PEMS emission data; establishing the mapping relationship between the VSP intervals and PEMS emission data includes: establishing mapping relationships between the VSP intervals in the VSP interval set and the PEMS emission data respectively, specifically by taking the average value of the instantaneous PEMS emission data corresponding to all VSP values ​​in the VSP interval as the image of the mapping relationship, and using the VSP interval as the preimage to perform curve fitting using the least squares method, thereby obtaining the mapping relationship between the VSP intervals and PEMS emission data; selecting the optimal mapping relationship based on the correlation coefficient method, and obtaining the corresponding optimal data adjustment scheme; Theoretical emission data are calculated based on the driving parameters corresponding to the actual OBD emission data over time and the mapping relationship described above. Confidence intervals are constructed using the theoretical emission data, and outliers in the actual OBD emission data during the detection phase are removed based on the confidence intervals.

2. The method according to claim 1, characterized in that, The VSP range is obtained by taking driving parameters corresponding to OBD emission data over time during the experimental phase, including: The VSP value is calculated based on the driving parameters corresponding to the OBD emission data during the experimental phase over time. The VSP value is divided into VSP intervals based on driving events.

3. The method according to claim 1, characterized in that, The calculation of theoretical emission data based on the driving parameters corresponding to the actual OBD emission data in time and the mapping relationship includes: The OBD emission data of the actual detection stage are adjusted according to the optimal data adjustment scheme, and the adjusted driving parameters corresponding to the time are obtained. Calculate the VSP value based on the adjusted driving parameters and obtain the optimal VSP range; The theoretical emission data are obtained based on the optimal VSP interval and the optimal mapping relationship.

4. The method according to claim 1, characterized in that, The method further includes: establishing a second mapping relationship between the OBD emission data and the PEMS emission data during the experimental phase; A data correction method is selected based on the actual OBD emission data during the detection phase and the confidence interval.

5. The method according to claim 4, characterized in that, The method for selecting data correction based on the actual OBD emission data during the detection phase and the confidence interval includes: When the emission data of OBD emission data at a certain point in the actual detection phase is outside the confidence interval, the optimal mapping relationship is selected for adjustment. When the emission data of OBD emission data at a certain time point in the actual detection phase is within the confidence interval, the second mapping relationship is selected for adjustment.

6. An OBD remote emission monitoring data correction system, characterized in that, The system includes: The data acquisition module obtains the VSP interval based on the driving parameters corresponding to the OBD emission data in the experimental phase over time; performs a preliminary data quality check on all OBD data in the experimental phase to obtain the time error range; adjusts the OBD emission data in the experimental phase according to the time error range, and obtains the VSP interval set based on the emission data after each adjustment. The mapping module establishes a mapping relationship between the VSP intervals and PEMS emission data. This establishment includes: establishing mapping relationships between each VSP interval in the VSP interval set and the PEMS emission data; specifically, the average value of the instantaneous PEMS emission data corresponding to all VSP values ​​in the VSP interval is taken as the image of the mapping relationship, and the VSP interval is used as the preimage for curve fitting using the least squares method to obtain the mapping relationship between the VSP intervals and the PEMS emission data; the optimal mapping relationship is selected based on the correlation coefficient method, and the corresponding optimal data adjustment scheme is obtained. The comparison model module calculates theoretical emission data based on the driving parameters corresponding to the actual OBD emission data in time during the detection phase and the mapping relationship. The correction module uses the theoretical emission data to create a confidence interval and removes outliers in the OBD emission data based on the confidence interval.

7. The system according to claim 6, characterized in that, The system also includes: The second mapping module establishes a second mapping relationship between the OBD emission data and the PEMS emission data during the experimental phase. The pattern recognition module selects a data correction method based on the actual OBD emission data during the detection phase and the confidence interval.

8. An electronic device, characterized in that, include: A memory and a processor, the memory and the processor being communicatively connected to each other, the memory storing computer instructions, the processor executing the computer instructions to perform the method as described in any one of claims 1-5.

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