A vehicle evaporative emission pollutant detection traceability method and system

Abstract

The application discloses a whole vehicle evaporative emission pollutant detection tracing method and system, relates to the technical field of evaporative emission detection, and comprises the following steps: performing evaporative experiments on a whole vehicle and different subsystems of the vehicle respectively, so as to obtain whole vehicle evaporative emission results and evaporative emission results of each subsystem; screening characteristic pollutants of the subsystems, and respectively determining the proportion of each characteristic pollutant in the total evaporative emission mass of the corresponding subsystem and the total evaporative emission mass of the whole vehicle; at each sampling moment, the contribution rate of each subsystem to the total evaporative emission mass of the whole vehicle is obtained according to the proportion of the characteristic pollutants of the subsystems in the total evaporative emission mass of the corresponding subsystem and in the total evaporative emission mass of the whole vehicle, the main evaporative emission subsystem is identified according to the contribution rate change of continuous multiple sampling moments, and the main pollutant is determined. The whole vehicle and the subsystems of the vehicle are subjected to identification and quantitative measurement of multiple pollutants, so that accurate tracing and fine management optimization of the evaporative emission pollutants of the vehicle are met.

Description

Technical Field

[0001] This invention relates to the field of evaporative emission detection technology, and in particular to a method and system for tracing the source of evaporative emission pollutants from a vehicle. Background Technology

[0002] As regulations concerning evaporative emissions from motor vehicles become increasingly stringent, the limits for total hydrocarbons (THC) in these emissions are tightening, making it more challenging to optimize vehicle evaporative emission performance. Simultaneously, consumers are increasingly concerned about the in-vehicle environment, paying closer attention to the environmental friendliness of vehicle materials and being highly concerned about high-risk carcinogens and other pollutants harmful to human health generated from the evaporation of these materials.

[0003] Currently, some studies have proposed methods for detecting and analyzing the contribution of evaporative emissions from automotive non-fuel system components. However, these methods only measure the THC emissions of different subsystems separately and do not conduct more refined measurements for specific pollutants, making it difficult to further optimize high-emission subsystems.

[0004] Other studies have proposed methods for detecting the odor of vaporized substances from non-metallic materials in automotive interiors, but these only test a single material in the vehicle interior and do not assess high concentrations of high-risk substances in the vehicle or identify their sources. Summary of the Invention

[0005] To address the aforementioned issues, this invention proposes a method and system for detecting and tracing pollutants emitted from vehicles. This system identifies and quantitatively measures various pollutants in the entire vehicle and its different subsystems, thereby enabling accurate tracing and refined management optimization of vehicle evaporative emission pollutants.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: In a first aspect, the present invention provides a method for detecting and tracing the source of evaporative emissions pollutants from a vehicle, comprising: The total evaporative emissions mass of the vehicle is obtained based on the acquired evaporative emissions results. The total evaporative emission mass of each subsystem is obtained based on the evaporative emission results of different vehicle subsystems. Based on the evaporative emission results of each subsystem, characteristic pollutants of each subsystem are screened, and the proportion of each characteristic pollutant in the total evaporative emission mass of the corresponding subsystem and the total evaporative emission mass of the vehicle are determined respectively. At each sampling time, the source contribution matrix is ​​formed by the proportion of each characteristic pollutant of each subsystem in the total evaporative emission mass of the corresponding subsystem, and the observation data matrix is ​​formed by the proportion of each characteristic pollutant of each subsystem in the total evaporative emission mass of the vehicle. Based on the source contribution matrix and the observation data matrix, the contribution rate of each subsystem to the total evaporative emission mass of the vehicle is calculated by positive definite matrix factorization. The main evaporative emission subsystems are identified by the change in contribution rate at multiple consecutive sampling times. The main pollutants are determined by the proportion of each characteristic pollutant in the total evaporative emission mass of the corresponding subsystem.

[0007] As an alternative implementation method, by conducting evaporation experiments on the whole vehicle and each subsystem separately, and performing full-spectrum pollutant analysis on the collected evaporation gas samples, the evaporation emission results of the whole vehicle and the evaporation emission results of the subsystems are obtained respectively; the evaporation emission results include pollutants and their corresponding volume concentrations.

[0008] As an alternative implementation method, the total evaporative emissions mass of the vehicle is the total evaporative emissions mass of all pollutants in the vehicle evaporation experiment at the sampling time point. The total mass of evaporative emissions; Among them, pollutants in the whole vehicle evaporation test At the sampling time point Evaporation emission quality for: ; ; in, Pollutants in the whole vehicle evaporation test At the sampling time point mass concentration; Pollutants in the whole vehicle evaporation test At the sampling time point Volume concentration; It is a pollutant The density; It refers to the volume of the sealed chamber used for testing evaporative emissions from a complete vehicle.

[0009] As an alternative implementation method, the subsystem The total evaporative emissions mass of the subsystem In the evaporation experiment, all pollutants were sampled at the following time points. The total mass of evaporative emissions; Among them, subsystem In the evaporation experiment, pollutants At the sampling time point Evaporation emission quality for: ; ; in, It is a subsystem In the evaporation experiment, pollutants At the sampling time point mass concentration; It is a subsystem In the evaporation experiment, pollutants At the sampling time point Volume concentration; It is a pollutant The density; It is the volume of the sealed chamber for the subsystem evaporation emission test.

[0010] As an alternative implementation, the process of screening characteristic contaminants for each subsystem includes: Based on the evaporation emission results of each subsystem, the evaporation emission mass of pollutant I in each subsystem is sorted from largest to smallest, and the top n1 pollutants in the evaporation emission mass ranking of each subsystem are selected as the core characteristic pollutants of the subsystem. Within each subsystem, the candidate sorting intervals Pollutants within the system are selected as candidate pollutants. Each candidate pollutant is compared to its evaporation emission ranking in other subsystems. Only those pollutants that are in the supplementary ranking range in all other subsystems are retained. The pollutants within are used as a supplementary set of candidate pollutants for the subsystem; among them, the candidate sorting intervals and supplementary sorting interval Non-overlapping ,but ; If the set of supplementary candidate pollutants is empty, then pollutants ranked n1+a+1 and thereafter will be included in the sorting interval to form the candidate sorting range. , At this point, supplement the sorting interval middle, The range of values ​​changes as follows ; Until the supplementary candidate pollutant set is not empty, at least one pollutant is selected from the finally determined supplementary candidate pollutant set as a supplementary characteristic pollutant of the subsystem; where n1, n2, a, and m are all positive integers; The core characteristic pollutant and the supplementary characteristic pollutant are integrated to form the final characteristic pollutant of the subsystem, and the number of characteristic pollutants in all subsystems is the same.

[0011] As an alternative implementation, the process of identifying major evaporative emission subsystems and determining major pollutants includes: Based on the change in contribution rate at multiple consecutive sampling times, the subsystem with the largest change is identified as the main evaporative emission subsystem. Based on the proportion of each characteristic pollutant in the total evaporative emission mass of the corresponding subsystem in the main evaporative emission subsystem, the pollutant with the largest proportion is identified as the main pollutant.

[0012] Secondly, the present invention provides a vehicle evaporative emission pollutant detection and traceability system, comprising: The vehicle emissions testing module is configured to obtain the total evaporative emissions mass of the vehicle based on the acquired vehicle evaporative emissions results; The subsystem emission test module is configured to obtain the total evaporative emission mass of each subsystem based on the evaporative emission results of different vehicle subsystems. The subsystem emission analysis module is configured to screen characteristic pollutants of each subsystem based on the evaporative emission results of each subsystem, and determine the proportion of each characteristic pollutant in the total evaporative emission mass of the corresponding subsystem and the total evaporative emission mass of the vehicle. The contribution rate calculation module is configured to, at each sampling time, construct a source contribution matrix by the proportion of each characteristic pollutant of each subsystem in the total evaporative emission mass of the corresponding subsystem, and construct an observation data matrix by the proportion of each characteristic pollutant of each subsystem in the total evaporative emission mass of the vehicle. Based on the source contribution matrix and the observation data matrix, the contribution rate of each subsystem to the total evaporative emission mass of the vehicle is calculated by positive definite matrix factorization. The source tracing and detection module is configured to identify the main evaporative emission subsystems based on the changes in contribution rates at multiple consecutive sampling times, and to determine the main pollutants based on the proportion of each characteristic pollutant in the total evaporative emission mass of the corresponding subsystem.

[0013] Thirdly, the present invention provides an electronic device including a memory and a processor, and computer instructions stored in the memory and running on the processor, wherein the computer instructions, when executed by the processor, perform the method described in the first aspect.

[0014] Fourthly, the present invention provides a computer-readable storage medium for storing computer instructions, which, when executed by a processor, perform the method described in the first aspect.

[0015] Fifthly, the present invention provides a computer program product, including a computer program that, when executed by a processor, implements the method described in the first aspect.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows: This invention proposes a method and system for detecting and tracing pollutants in vehicle evaporative emissions. By conducting evaporation experiments on the entire vehicle and its subsystems, and performing full-spectrum pollutant analysis on the collected evaporative gas samples, it can not only accurately obtain the overall evaporative emission results of the entire vehicle and its subsystems, but also identify and quantitatively measure various specific pollutants. This overcomes the limitations of existing detection methods that only measure total emissions, not individual pollutants, only measure single locations, and do not cover the entire system, thus meeting the practical needs of refined management of vehicle evaporative emission pollutants. Furthermore, by screening characteristic pollutants in each subsystem, the emission amount of characteristic pollutants and their proportion in the total emission of the corresponding subsystem are determined. Then, by combining the observation data matrix and the source contribution matrix, the contribution rate of characteristic pollutants in each subsystem to the vehicle's evaporative emissions can be accurately calculated. This allows for clear identification of the specific sources of high-risk pollutants in vehicle evaporative emissions, providing a clear target basis for the precise control of high-risk pollutants and the reduction of pollutant emissions from inside the vehicle and the environment.

[0017] Advantages of additional aspects of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0019] Figure 1 This is a flowchart of the vehicle evaporative emission pollutant detection and tracing method provided in Embodiment 1 of the present invention; Figure 2 The ambient temperature curves and sampling time points of the whole vehicle and Mini-SHED evaporator chamber during the 5-day test provided in Embodiment 1 of the present invention; Figure 3 This is a schematic diagram of GC-MS analysis data for vehicle evaporative emission testing provided in Embodiment 1 of the present invention. Detailed Implementation

[0020] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0021] It should be noted that the following detailed descriptions are exemplary and intended to provide further illustration of the invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0022] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention. As used herein, unless the context clearly indicates otherwise, the singular form is intended to include the plural form as well. Furthermore, it should be understood that the terms “comprising” and “including”, and any variations thereof, are intended to cover non-exclusive inclusion, for example, a process, method, system, product, or apparatus that includes a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0023] Where there is no conflict, the embodiments and features in the embodiments of the present invention can be combined with each other.

[0024] Example 1 This embodiment proposes a method for tracing the source of evaporative emissions pollutants from vehicles, such as... Figure 1 As shown, it includes: S101: Obtain the total evaporative emissions mass of the vehicle based on the obtained evaporative emissions results of the vehicle; S102: Obtain the total evaporative emission mass of each subsystem based on the obtained evaporative emission results of different vehicle subsystems; S103: Based on the evaporative emission results of each subsystem, screen the characteristic pollutants of each subsystem, and determine the proportion of each characteristic pollutant in the total evaporative emission mass of the corresponding subsystem and the total evaporative emission mass of the vehicle. S104: At each sampling time, the source contribution matrix is ​​formed by the proportion of each characteristic pollutant of each subsystem in the total evaporative emission mass of the corresponding subsystem, and the observation data matrix is ​​formed by the proportion of each characteristic pollutant of each subsystem in the total evaporative emission mass of the vehicle. Based on the source contribution matrix and the observation data matrix, the contribution rate of each subsystem to the total evaporative emission mass of the vehicle is calculated by positive definite matrix factorization. S105: Identify the main evaporative emission subsystems based on the changes in contribution rates at multiple consecutive sampling times, and determine the main pollutants based on the proportion of each characteristic pollutant in the total evaporative emission mass of the corresponding subsystem.

[0025] In this embodiment, by conducting evaporation experiments on the whole vehicle and each subsystem of the vehicle, and by performing full-spectrum pollutant analysis on the collected evaporation gas samples, the evaporation emission results of the whole vehicle and the evaporation emission results of the subsystems are obtained.

[0026] Before conducting evaporation tests on the entire vehicle and its subsystems, the condition of the test vehicle and its corresponding major subsystems (such as the fuel system, tires, seats, etc.) is first inspected to ensure they are in good condition and free of external volatile contaminants that could interfere with the test. If the vehicle includes a fuel system, commercially available fuel is added to the fuel tank to 40% of its capacity. If the vehicle is a pure electric vehicle, fuel system-related tests are not performed.

[0027] In this embodiment, in step S101, a multi-day evaporation experiment is conducted on the whole vehicle in the sealed chamber for the whole vehicle evaporation emission test, and the collected evaporation gas samples are subjected to full-spectrum pollutant analysis to obtain the whole vehicle evaporation emission results.

[0028] Specifically: Using a sealed test chamber for vehicle evaporative emissions that meets relevant standards, the test vehicle is pushed into the chamber, and the windows and trunk are opened. Figure 2 The ambient temperature curve shown indicates that the vehicle is subjected to a static evaporative emission test under variable ambient temperature. The total test time can be set to 5 days.

[0029] During the test, gaseous evaporating pollutants inside the chamber were sampled at set time intervals, such as 12 hours, using a SUMMA canister through the sampling port on the side wall of the sealed chamber. The SUMMA canister was initially in a negative pressure vacuum state. After sampling began, gas inside the chamber was rapidly drawn in until the gas pressure was equalized with the chamber's internal pressure. The total sampling volume was 15L.

[0030] After sampling, the collected gaseous evaporation pollutant samples were analyzed using gas chromatography-mass spectrometry (GC-MS) to obtain the volume concentration of each pollutant in ppb. The analytical results are as follows: Figure 3 As shown.

[0031] Furthermore, the mass concentration of each pollutant can be obtained from equation (1): (1); in, Pollutants in whole vehicle evaporation tests At the sampling time point The mass concentration, in mg / m³ 3 ; Pollutants in whole vehicle evaporation tests At the sampling time point Volume concentration, in ppb; It is a pollutant The density is expressed in g / L.

[0032] Based on the volume of the sealed chamber used for whole-vehicle evaporative emission testing, calculate the evaporative emission mass of each pollutant: (2); in, Pollutants in whole vehicle evaporation tests At the sampling time point Evaporation emissions mass, in mg; This is the volume of the sealed chamber used for whole vehicle evaporative emission testing, in meters (m). 3 .

[0033] Total evaporative emissions from a vehicle are the total emissions of all pollutants during the vehicle evaporation test at the sampling time point. The total mass of evaporative emissions.

[0034] In this embodiment, in step S102, a multi-day evaporation experiment is conducted on different subsystems of the vehicle in the component evaporation chamber, and the collected evaporation gas samples are subjected to full-spectrum pollutant analysis to obtain the evaporation emission results of each subsystem.

[0035] Specifically: Using the Mini-SHED evaporative emission test chamber, components from the same model of fuel system, tires, seats, and other subsystems of the test vehicle were placed separately into the Mini-SHED evaporative emission test chamber, and then... Figure 2 The ambient temperature curve shown is used for static evaporative emission testing under variable ambient temperature. The test time is the same as the test time for the whole vehicle, such as 5 days.

[0036] During the test, at set time intervals, such as 12 hours, gaseous evaporative pollutants inside the Mini-SHED evaporative emission test chamber were sampled using a SUMMA canister through the reserved sampling port. The SUMMA canister was initially in a negative pressure vacuum state. After sampling began, gas was rapidly drawn into the chamber until the gas pressure was equalized with the chamber's internal pressure. The total sampling volume was 15L.

[0037] After sampling, the collected evaporative pollutant samples were analyzed using a GC-MS analyzer to obtain the volume concentration of each pollutant, in ppb.

[0038] Furthermore, the mass concentration of each pollutant can be obtained from equation (3): (3); in, It is a subsystem In the evaporation test of pollutants At the sampling time point The mass concentration, in mg / m³ 3 ; It is a subsystem In the evaporation test of pollutants At the sampling time point Volume concentration, in ppb; It is a pollutant The density is expressed in g / L.

[0039] Based on the volume of the Mini-SHED evaporative emission test chamber, calculate the evaporative emission mass of each pollutant: (4); in, It is a subsystem In the evaporation test of pollutants At the sampling time point Evaporation emissions mass, in mg; This is the volume of the Mini-SHED evaporative emission test chamber, in meters (m³). 3 .

[0040] Subsystem The total evaporative emissions mass of the subsystem In the evaporation test, all pollutants were at the sampling time point The total mass of evaporative emissions.

[0041] In this embodiment, step S103, the process of screening characteristic pollutants for each subsystem based on the evaporation emission results of each subsystem, includes: (1) Based on the evaporation emission results of each subsystem, the evaporation emission mass of the common pollutant I in each subsystem is sorted from largest to smallest, and the pollutants with the highest evaporation emission mass in each subsystem are selected as the core characteristic pollutants of that subsystem.

[0042] (2) Within each subsystem, the candidate sorting intervals Pollutants within the system are selected as candidate pollutants. Each candidate pollutant is then compared to its evaporation emission quality ranking in all other subsystems. Only those pollutants that are within the supplementary ranking range in all other subsystems are retained. The pollutants within the system form a supplementary set of candidate pollutants for this subsystem.

[0043] In this step, the candidate sorting interval and supplementary sorting interval Non-overlapping ,but And n1, n2, and a are all positive integers.

[0044] (3) If the supplementary candidate pollutant set is empty, the range of the candidate interval of the current subsystem is gradually expanded, and pollutants at the n1+a+1th position before sorting and thereafter are successively included to form the candidate sorting interval. , And at this time, supplement the sorting interval middle, The range of values ​​changes as follows .

[0045] Because it is necessary to ensure the selection range and supplementary sorting interval Non-overlapping ,but n1, n2, a, and m are all positive integers.

[0046] Then, the cross-subsystem comparison and screening is repeated until the supplementary candidate pollutant set is not empty. From the finally determined supplementary candidate pollutant set, at least one pollutant is selected as the supplementary characteristic pollutant for each subsystem.

[0047] Where, when m equals At that time, it is considered as having no supplementary characteristic pollutants.

[0048] (4) Integrate the core characteristic pollutants and supplementary characteristic pollutants to form the final characteristic pollutants of each subsystem, and complete the screening and determination of characteristic pollutants. Among them, the number N of characteristic pollutants in all subsystems is the same.

[0049] For example, if there are 20 pollutants in each subsystem, the top 5 pollutants in terms of evaporation emission quality in each subsystem are selected as the core characteristic pollutants of that subsystem. The pollutants ranked 6th to 10th in each subsystem are selected as the first round of candidate pollutants. The emission quality ranking of each candidate pollutant is compared with that of all other subsystems. Only pollutants that are in the bottom 5 range of emission quality in all other subsystems are retained to form a supplementary candidate pollutant set for that subsystem. If the set is not empty, supplementary characteristic pollutants are selected for each subsystem.

[0050] It is understandable that the values ​​of n1, n2, a, and m can be customized according to actual needs, and this embodiment does not limit their values.

[0051] In this embodiment, in step S103, each sampling time point is calculated. The proportion of each characteristic pollutant in the total evaporative emissions of the corresponding subsystem: (5); in, At the sampling time point Subsystem Characteristic pollutants In subsystem The percentage of total evaporative emissions by mass, expressed in % It is a subsystem Characteristic pollutants in evaporation tests At the sampling time point Evaporation emissions mass, in mg; It is a subsystem At the sampling time point Total evaporative emissions, expressed in mg.

[0052] Calculate each sampling time point Subsystem Each characteristic pollutant Percentage of total evaporative emissions in the vehicle's total mass: (6); in, At the sampling time point Subsystem Characteristic pollutants The percentage of total evaporative emissions in the vehicle's total evaporative mass, expressed as % At the sampling time point Subsystem Characteristic pollutants Evaporative emissions mass during vehicle testing, expressed in mg; Sampling time point Total evaporative emissions of the vehicle, expressed in mg.

[0053] This step can focus on high-emission characteristic pollutants specific to different subsystems. For example: toluene, methyl tert-butyl ether, and cyclopentane are selected from the evaporative emissions results of the fuel system; acrolein, benzo[a]pyrene, and carbon disulfide are selected from the evaporative emissions results of the tires; and tetrachloromethane, benzene, and hexanol are selected from the evaporative emissions results of the vehicle seats.

[0054] Table 1 shows examples of some substances and their corresponding volume concentrations identified in the evaporative emissions results of the whole vehicle and some subsystems.

[0055] Table 1. Substances and volume concentrations; .

[0056] In this embodiment, the specific implementation process of steps S104-S105 is as follows: (1) At each sampling time By comparing the evaporative emissions of the whole vehicle with the evaporative emissions of each subsystem, an observation data matrix is ​​constructed from the proportion of each characteristic pollutant of each subsystem in the total evaporative emissions of the whole vehicle. ;

[0057] Where N is the number of characteristic pollutants in subsystem k; At the sampling time point Subsystem Characteristic pollutants The proportion of total evaporative emissions in the total mass of the vehicle.

[0058] (2) The source contribution matrix is ​​composed of the proportion of each characteristic pollutant in the total evaporative emission mass of the corresponding subsystem. ;

[0059] in, At the sampling time point Subsystem Characteristic pollutants In subsystem The percentage of total evaporative emissions by mass.

[0060] (3) Combining the uncertainty matrix consisting of parametric errors and uncertainties By using positive definite matrix factorization, the contribution rate matrix of characteristic pollutants in each subsystem to the total evaporative emissions of the vehicle at each sampling time is calculated. The contribution rate matrix G1 is calculated using the formula X1=G1×F1+U1.

[0061] Positive definite matrix factorization is a weighted least squares matrix factorization model with non-negative constraints. Its core purpose is to extract latent factors from complex observation data and quantify their contributions. It is the mainstream method for source apportionment of atmospheric environmental pollutants. Here, it is extended to the vehicle evaporative emission method.

[0062] In the process of decomposing the data matrix, not only the observations themselves are considered, but also their corresponding uncertainties (such as sampling errors, analysis errors, etc.). The diagonal weight matrix constructed from the uncertainty of each data point is the uncertainty matrix.

[0063] in,

[0064] In the formula, At the sampling time point Subsystem Characteristic pollutants The uncertainty value.

[0065] The following example uses four subsystems as examples. The five pollutants with the highest evaporative emission mass in each subsystem and three pollutants with lower evaporative emission mass in other subsystems are selected as characteristic pollutants. There are a total of eight characteristic pollutants in each subsystem. Based on equal time intervals, the proportion of each characteristic pollutant in the total evaporative emission mass of the corresponding subsystem and the total evaporative emission mass of the vehicle are measured three times, and the matrix is ​​recorded respectively.

[0066] During the first sampling, the matrices were as follows:

[0067]

[0068]

[0069] Therefore, during the first sampling, the contribution rate matrix G1 of different subsystems to the total evaporative emissions mass of the vehicle is calculated using the formula: X1 = G1 × F1 + U1. Similarly, the subsystem contribution rate matrices G2 and G3 for the second and third sampling are obtained.

[0070] (4) Based on the change in the contribution rate of each subsystem to the total evaporative emissions of the vehicle at multiple consecutive sampling times, the subsystem with the largest change is the main evaporative emission subsystem; based on the proportion of each characteristic pollutant in the total evaporative emissions of the corresponding subsystem in the main evaporative emission subsystem, the pollutant with the largest proportion is the main pollutant, thereby optimizing the control of the main pollutant in the subsystem.

[0071] In this matrix, each element represents the contribution rate of the corresponding subsystem to the total evaporative emissions mass of the vehicle. For multiple consecutive sampling times, the absolute value of the difference between corresponding elements in the contribution rate matrix of the same subsystem at adjacent times is calculated to obtain the change in the contribution rate of the subsystem to the total evaporative emissions mass of the vehicle. The subsystem with the largest change in contribution rate is the main evaporative emission subsystem. The proportion of all characteristic pollutants in the subsystem to the total evaporative emissions of the corresponding subsystem is compared horizontally, and the largest amount is selected as the main pollutant of the subsystem, which is then used as the basis for pollutant emission reduction.

[0072] The above solution effectively addresses the core pain points of existing technologies, such as insufficient precision in vehicle evaporative emission detection, inability to accurately trace the source of high-risk pollutants, and lack of data support for subsystem optimization. Specifically: First, it fills the gap in the precision of existing detection methods, achieving comprehensive and accurate measurement of evaporative emissions. Existing technologies either only measure THC emissions for different subsystems without precise detection of specific pollutants, or only conduct odor tests on a single interior material, failing to cover the full spectrum of pollutants from the entire vehicle and its subsystems. This solution conducts evaporation experiments on the entire vehicle and each vehicle subsystem separately, and performs full-spectrum pollutant analysis on the collected evaporative gas samples. This not only accurately obtains the overall evaporative emissions results for the entire vehicle and its subsystems, but also enables the identification and quantitative measurement of multiple specific pollutants. It overcomes the limitations of existing detection methods that only measure total emissions, not individual pollutants, only measure single locations, and do not cover the entire system, thus meeting the practical needs for refined management of vehicle evaporative emissions.

[0073] Secondly, it enables precise source tracing of high-risk pollutants, providing a clear direction for pollution prevention and control. Existing technologies cannot assess high concentrations of high-risk substances inside vehicles, nor can they identify their sources, leading to a lack of targeted optimization of subsystems. This solution screens characteristic pollutants in each subsystem, clarifies the emission volume of these characteristic pollutants and their proportion in the total emissions of the corresponding subsystem, and then, by combining the observation data matrix with the source contribution matrix, accurately calculates the contribution rate of characteristic pollutants in each subsystem to the vehicle's evaporative emissions. This clearly identifies the specific sources of high-risk pollutants in the vehicle's evaporative emissions, and clarifies which subsystems and which characteristic pollutants are the main contributors to the vehicle's emissions, providing a clear and targeted basis for precise control of high-risk pollutants and reduction of pollutant emissions from inside vehicles and the environment.

[0074] Third, this solution provides strong data support for the refined optimization and improvement of vehicle subsystems, thereby promoting the improvement of vehicle environmental performance. Existing technologies, lacking full-spectrum pollutant data and source tracing information, struggle to target and optimize high-emission subsystems. This solution, through full-spectrum pollutant detection and precise source tracing, not only clarifies the emission levels and pollution contributions of each subsystem but also accurately identifies key pollutants and subsystems affecting overall vehicle emissions. This provides detailed and accurate data support for the optimization and improvement of non-fuel system components, interior materials, and other subsystems, helping companies to specifically improve production processes and select environmentally friendly materials, thereby reducing evaporative emissions from subsystems and the entire vehicle, and improving product environmental performance.

[0075] Fourth, it enhances the scientific and systematic nature of vehicle evaporative emission management, balancing environmental protection and human health. This solution combines whole-vehicle testing with subsystem testing, and full-spectrum pollutant analysis with characteristic pollutant tracing, constructing a complete whole-vehicle evaporative emission pollutant detection and tracing system. This not only meets the vehicle industry's evaporative emission compliance testing needs but also effectively identifies high-concentration, high-risk pollutants that endanger human health, achieving systematic and scientific management of evaporative emissions.

[0076] Example 2 This embodiment provides a vehicle evaporative emission pollutant detection and traceability system, including: The vehicle emissions testing module is configured to obtain the total evaporative emissions mass of the vehicle based on the acquired vehicle evaporative emissions results; The subsystem emission test module is configured to obtain the total evaporative emission mass of each subsystem based on the evaporative emission results of different vehicle subsystems. The subsystem emission analysis module is configured to screen characteristic pollutants of each subsystem based on the evaporative emission results of each subsystem, and determine the proportion of each characteristic pollutant in the total evaporative emission mass of the corresponding subsystem and the total evaporative emission mass of the vehicle. The contribution rate calculation module is configured to, at each sampling time, construct a source contribution matrix by the proportion of each characteristic pollutant of each subsystem in the total evaporative emission mass of the corresponding subsystem, and construct an observation data matrix by the proportion of each characteristic pollutant of each subsystem in the total evaporative emission mass of the vehicle. Based on the source contribution matrix and the observation data matrix, the contribution rate of each subsystem to the total evaporative emission mass of the vehicle is calculated by positive definite matrix factorization. The source tracing and detection module is configured to identify the main evaporative emission subsystems based on the changes in contribution rates at multiple consecutive sampling times, and to determine the main pollutants based on the proportion of each characteristic pollutant in the total evaporative emission mass of the corresponding subsystem.

[0077] It should be noted that the above modules correspond to the steps described in Embodiment 1, and the examples and application scenarios implemented by the above modules and the corresponding steps are the same, but are not limited to the content disclosed in Embodiment 1. It should also be noted that the above modules, as part of the system, can be executed in a computer system such as a set of computer-executable instructions.

[0078] In further embodiments, the following is also provided: An electronic device includes a memory and a processor, as well as computer instructions stored in the memory and running on the processor, wherein the computer instructions, when executed by the processor, perform the method described in Embodiment 1. For brevity, further details are omitted here.

[0079] It should be understood that in this embodiment, the processor can be a central processing unit (CPU), or it can be other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor can be a microprocessor or any conventional processor, etc.

[0080] Memory may include read-only memory and random access memory, and provides instructions and data to the processor. A portion of memory may also include non-volatile random access memory. For example, memory may also store information about the device type.

[0081] A computer-readable storage medium for storing computer instructions, which, when executed by a processor, perform the method described in Embodiment 1.

[0082] The method in Example 1 can be directly implemented by a hardware processor, or implemented by a combination of hardware and software modules within the processor. The software modules can reside in readily available storage media in the field, such as random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, or registers. This storage medium is located in memory, and the processor reads information from the memory and, in conjunction with its hardware, completes the steps of the above method. To avoid repetition, a detailed description is not provided here.

[0083] A computer program product includes a computer program that, when executed by a processor, implements the method described in Embodiment 1.

[0084] The present invention also provides at least one computer program product tangibly stored on a non-transitory computer-readable storage medium. The computer program product includes computer-executable instructions, such as instructions included in program modules, which execute in a device on a target real or virtual processor to perform the processes / methods described above. Typically, program modules include routines, programs, libraries, objects, classes, components, data structures, etc., that perform specific tasks or implement specific abstract data types. In various embodiments, the functionality of program modules can be combined or divided among program modules as needed. The machine-executable instructions for the program modules can execute within a local or distributed device. In a distributed device, the program modules can reside in both local and remote storage media.

[0085] The computer program code used to implement the methods of the present invention may be written in one or more programming languages. This computer program code may be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device, such that when executed by the computer or other programmable data processing device, the program code causes the functions / operations specified in the flowcharts and / or block diagrams to be implemented. The program code may be executed entirely on a computer, partially on a computer, as a stand-alone software package, partially on a computer and partially on a remote computer, or entirely on a remote computer or server.

[0086] In the context of this invention, computer program code or related data may be carried by any suitable carrier to enable a device, apparatus, or processor to perform the various processes and operations described above. Examples of carriers include signals, computer-readable media, and the like. Examples of signals may include electrical, optical, radio, sound, or other forms of propagation signals, such as carrier waves, infrared signals, etc.

[0087] Those skilled in the art will recognize that the units and algorithm steps described in connection with the various examples of this embodiment can be implemented in electronic hardware or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this invention.

[0088] While the specific embodiments of the present invention have been described above in conjunction with the accompanying drawings, this is not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art without creative effort based on the technical solutions of the present invention are still within the scope of protection of the present invention.

Claims

1. A method for detecting and tracing the source of pollutants emitted from a vehicle's evaporative emissions, characterized in that, include: The total evaporative emissions mass of the vehicle is obtained based on the acquired evaporative emissions results. The total evaporative emission mass of each subsystem is obtained based on the evaporative emission results of different vehicle subsystems. Based on the evaporative emission results of each subsystem, characteristic pollutants of each subsystem are screened, and the proportion of each characteristic pollutant in the total evaporative emission mass of the corresponding subsystem and the total evaporative emission mass of the vehicle are determined respectively. At each sampling time, the source contribution matrix is ​​formed by the proportion of each characteristic pollutant of each subsystem in the total evaporative emission mass of the corresponding subsystem, and the observation data matrix is ​​formed by the proportion of each characteristic pollutant of each subsystem in the total evaporative emission mass of the vehicle. Based on the source contribution matrix and the observation data matrix, the contribution rate of each subsystem to the total evaporative emission mass of the vehicle is calculated by positive definite matrix factorization. The main evaporative emission subsystems are identified by the change in contribution rate at multiple consecutive sampling times. The main pollutants are determined by the proportion of each characteristic pollutant in the total evaporative emission mass of the corresponding subsystem.

2. The method for detecting and tracing pollutants emitted from a vehicle as described in claim 1, characterized in that, Evaporation experiments were conducted on the whole vehicle and each subsystem, and the collected evaporation gas samples were analyzed for full-spectrum pollutants to obtain the evaporation emission results of the whole vehicle and the evaporation emission results of the subsystems. The evaporation emission results include pollutants and their corresponding volume concentrations.

3. The method for detecting and tracing pollutants emitted from a vehicle as described in claim 1, characterized in that, The total evaporative emissions of the vehicle are the total emissions of all pollutants in the vehicle evaporation test at the sampling time point. The total mass of evaporative emissions; Among them, pollutants in the whole vehicle evaporation test At the sampling time point Evaporation emission quality for: ； ； in, Pollutants in the whole vehicle evaporation test At the sampling time point mass concentration; Pollutants in the whole vehicle evaporation test At the sampling time point Volume concentration; It is a pollutant The density; It refers to the volume of the sealed chamber used for testing evaporative emissions from a complete vehicle.

4. The method for detecting and tracing pollutants emitted from a vehicle as described in claim 1, characterized in that, Subsystem The total evaporative emissions mass of the subsystem In the evaporation experiment, all pollutants were sampled at the following time points. The total mass of evaporative emissions; Among them, subsystem In the evaporation experiment, pollutants At the sampling time point Evaporation emission quality for: ； ； in, It is a subsystem In the evaporation experiment, pollutants At the sampling time point mass concentration; It is a subsystem In the evaporation experiment, pollutants At the sampling time point Volume concentration; It is a pollutant The density; It is the volume of the sealed chamber for the subsystem evaporation emission test.

5. The method for detecting and tracing pollutants emitted from a vehicle as described in claim 1, characterized in that, The process of screening characteristic contaminants for each subsystem includes: Based on the evaporation emission results of each subsystem, the evaporation emission mass of pollutant I in each subsystem is sorted from largest to smallest, and the top n1 pollutants in the evaporation emission mass ranking of each subsystem are selected as the core characteristic pollutants of the subsystem. Within each subsystem, the candidate sorting intervals Pollutants within the system are selected as candidate pollutants. Each candidate pollutant is compared to its evaporation emission ranking in other subsystems. Only those pollutants that are in the supplementary ranking range in all other subsystems are retained. The pollutants within are used as a supplementary set of candidate pollutants for the subsystem; among them, the candidate sorting intervals and supplementary sorting interval Non-overlapping ,but ; If the set of supplementary candidate pollutants is empty, then pollutants ranked n1+a+1 and thereafter will be included in the sorting interval to form the candidate sorting range. , At this point, supplement the sorting interval. middle, The range of values ​​changes as follows ; Until the supplementary candidate pollutant set is not empty, at least one pollutant is selected from the finally determined supplementary candidate pollutant set as a supplementary characteristic pollutant of the subsystem; where n1, n2, a, and m are all positive integers; The core characteristic pollutant and the supplementary characteristic pollutant are integrated to form the final characteristic pollutant of the subsystem, and the number of characteristic pollutants in all subsystems is the same.

6. The method for detecting and tracing pollutants emitted from a vehicle as described in claim 1, characterized in that, The process of identifying major evaporative emission subsystems and determining major pollutants includes: Based on the change in contribution rate at multiple consecutive sampling times, the subsystem with the largest change is identified as the main evaporative emission subsystem. Based on the proportion of each characteristic pollutant in the total evaporative emission mass of the corresponding subsystem in the main evaporative emission subsystem, the pollutant with the largest proportion is identified as the main pollutant.

7. A vehicle evaporative emission pollutant detection and traceability system, characterized in that, include: The vehicle emissions testing module is configured to obtain the total evaporative emissions mass of the vehicle based on the acquired vehicle evaporative emissions results; The subsystem emission test module is configured to obtain the total evaporative emission mass of each subsystem based on the evaporative emission results of different vehicle subsystems. The subsystem emission analysis module is configured to screen characteristic pollutants of each subsystem based on the evaporative emission results of each subsystem, and determine the proportion of each characteristic pollutant in the total evaporative emission mass of the corresponding subsystem and the total evaporative emission mass of the vehicle. The contribution rate calculation module is configured to, at each sampling time, construct a source contribution matrix by the proportion of each characteristic pollutant of each subsystem in the total evaporative emission mass of the corresponding subsystem, and construct an observation data matrix by the proportion of each characteristic pollutant of each subsystem in the total evaporative emission mass of the vehicle. Based on the source contribution matrix and the observation data matrix, the contribution rate of each subsystem to the total evaporative emission mass of the vehicle is calculated by positive definite matrix factorization. The source tracing and detection module is configured to identify the main evaporative emission subsystems based on the changes in contribution rates at multiple consecutive sampling times, and to determine the main pollutants based on the proportion of each characteristic pollutant in the total evaporative emission mass of the corresponding subsystem.

8. An electronic device, characterized in that, It includes a memory and a processor, as well as computer instructions stored in the memory and running on the processor, which, when executed by the processor, perform the method according to any one of claims 1-6.

9. A computer-readable storage medium, characterized in that, Used to store computer instructions, which, when executed by a processor, perform the method described in any one of claims 1-6.

10. A computer program product, characterized in that, Includes a computer program, which, when executed by a processor, implements the method described in any one of claims 1-6.

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