CN117740228A - Method, system, equipment and medium for determining reliability of DPF differential pressure sensor - Google Patents

Method, system, equipment and medium for determining reliability of DPF differential pressure sensor Download PDF

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Publication number
CN117740228A
CN117740228A CN202311454211.8A CN202311454211A CN117740228A CN 117740228 A CN117740228 A CN 117740228A CN 202311454211 A CN202311454211 A CN 202311454211A CN 117740228 A CN117740228 A CN 117740228A
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China
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differential pressure
pressure sensor
determining
parameter
dpf differential
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解同鹏
鹿文慧
高翠
孔峰
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Weichai Power Co Ltd
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Weichai Power Co Ltd
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Priority to CN202311454211.8A priority Critical patent/CN117740228A/en
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    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T10/00—Road transport of goods or passengers
    • Y02T10/10—Internal combustion engine [ICE] based vehicles
    • Y02T10/40—Engine management systems

Abstract

The invention relates to a method, a system, equipment and a medium for determining the credibility of a DPF differential pressure sensor, wherein the method comprises the following steps: acquiring a first set of exhaust flow values in a current period and a second set of DPF differential pressure sensor measurement values in the current period; under the condition that the exhaust flow value in the first set meets the preset condition, determining a first parameter set corresponding to the linear relation between the measured value of the DPF differential pressure sensor and the exhaust flow value in the current period based on the first set, the second set and a least square parameter estimation method; determining whether each parameter in the first parameter set is within a preset range; under the condition that each parameter is determined to be in a preset range, determining that the measured value of the DPF differential pressure sensor is credible; or, in the case that any one of the first parameter set is determined not to be within the preset range, determining that the DPF differential pressure sensor measurement value is not trusted. A more accurate determination of the deviation of the DPF sensor measurements is achieved.

Description

Method, system, equipment and medium for determining reliability of DPF differential pressure sensor
Technical Field
The invention relates to the field of DPF differential pressure sensors, in particular to a method, a system, equipment and a medium for determining the credibility of a DPF differential pressure sensor.
Background
A DPF differential pressure sensor is utilized in a diesel aftertreatment system to estimate the carbon loading trapped in the DPF. As the DPF differential pressure sensor works in a high-temperature environment for a long time, the aging of the sensor, the accumulated water in the air taking pipe of the sensor and other reasons influence the output result of the sensor, the measured value of the sensor is deviated, and the measuring error is increased. If the pressure difference measured value is larger, the estimated value of the carbon loading is larger, so that the DPF is frequently regenerated, and the fuel consumption is increased; if the differential pressure measurement is small, the estimated carbon loading is small, while the actual carbon loading is large, and the risk of burning out may occur during DPF regeneration. Meanwhile, due to the deviation of the measured value of the sensor, great difficulty is brought to the related diagnosis (overload, filtration efficiency and the like) of the DPF, so that the diagnosis of the DPF is not reported wrong or is mistakenly reported wrong, the driving safety is influenced, and the after-sales service cost is increased. Therefore, how to determine whether there is a deviation in the measured value of the DPF sensor is a problem to be solved.
Disclosure of Invention
The invention provides a method, a system, equipment and a medium for determining the reliability of a DPF differential pressure sensor, which are used for solving the problem that whether the measured value of the DPF sensor has deviation or not can not be accurately determined in the prior art, and realizing more accurate determination of whether the measured value of the DPF sensor has deviation.
A method of determining the trustworthiness of a DPF differential pressure sensor, the method comprising: after the engine is started, acquiring a first set of exhaust flow values of the exhaust pipe in the current period and a second set of DPF differential pressure sensor measurement values in the current period; under the condition that the exhaust flow value in the first set meets the preset condition, determining a first parameter set corresponding to the linear relation between the DPF differential pressure sensor measured value and the exhaust flow value in the current period based on the first set, the second set and a least square parameter estimation method; determining whether each parameter in the first parameter set is within a preset range; under the condition that each parameter in the first parameter set is determined to be in a preset range, determining that the measured value of the DPF differential pressure sensor is reliable; or, in the case that any one of the first parameter set is determined not to be within a preset range, determining that the measured value of the DPF differential pressure sensor is not trusted.
In one embodiment, the determining that the exhaust flow value in the first set meets a preset condition includes: and determining that the exhaust flow values in the first set meet a preset condition under the condition that each exhaust flow value in the first set is determined to be larger than a first preset threshold value and the minimum exhaust flow value in the first set is smaller than or equal to a second preset threshold value and the maximum exhaust flow value in the first set is determined to be larger than or equal to a third preset threshold value.
In one embodiment, in the case that the exhaust pipe has an exhaust flow value of a volume flow value, the first preset threshold value is 45m 3 /h to 55m 3 Any number between/h, a second preset threshold value of 195m 3 /h to 205m 3 Any number between/h, a third preset threshold of 595m 3 /h to 605m 3 Any number between/h.
In one embodiment, the determining a first parameter set corresponding to a linear relationship between a measured value of a DPF differential pressure sensor and an exhaust gas flow value in a current period based on the first set, the second set, and a least squares parameter estimation method includes: determining an average of the individual exhaust flow values in the first set as an average of the independent variables; determining an average value of the measured values of each DPF differential pressure sensor in the second set as an average value of the dependent variable; determining a first coefficient before the independent variable according to each exhaust flow value in the first set and each DPF differential pressure sensor measurement value in the second set; a first intercept parameter is determined based on the average of the independent variables, the average of the dependent variables, and a first coefficient before the independent variables.
In one embodiment, the average value of the independent variables corresponds to a first expression:wherein (1)>For the average value of the individual exhaust flow values in the first set, x 1 、x 2 、x 3 ……x n For each exhaust flow value in the first set, n is the number of exhaust flow values in the first set; the average value of the dependent variable corresponds to the second expression: />Wherein (1)>Y, which is the average value of the measured values of the DPF differential pressure sensors in the second set 1 、y 2 、y 3 ……y n For each DPF differential pressure sensor measurement in the second set; the third expression corresponding to the first coefficient before the argument is: />b is the first coefficient before the argument, x i Represents the i-th exhaust flow value, y in the first set i An ith DPF differential pressure sensor measurement in the second set; the fourth expression corresponding to the first intercept parameter is: />A first set of parameters is determined based on the first coefficient b and the first intercept parameter a.
In one embodiment, before said determining whether each parameter of said first set of parameters is within a preset range, said method further comprises: determining a second parameter set of each period under the normal working condition of the DPF differential pressure sensor based on a third set of exhaust flow values of the exhaust pipe corresponding to each period, a fourth set of measurement values of the DPF differential pressure sensor and a least square parameter estimation method; and determining the range of each parameter in the second parameter set of each period based on the second parameter set of each period, and determining the range of each parameter in the second parameter set as a preset range.
In one embodiment, the second parameter set of each period includes a second coefficient before the independent variable of the DPF differential pressure sensor under the normal working condition, and a second intercept parameter, where a range of the second coefficient is a first preset range, a range of the second intercept parameter is a second preset range, and the determining whether each parameter in the first parameter set is in the preset range includes: determining whether the first coefficient is within a first preset range and determining whether the first intercept parameter is within a second preset range.
In one embodiment, the method further comprises: and if the exhaust flow value in the fifth set meets the preset condition, determining a third parameter set corresponding to the linear relation between the measured value of the DPF differential pressure sensor and the exhaust flow value of the exhaust pipe in a preset period based on the fifth set, the sixth set of the measured value of the DPF differential pressure sensor in the next period and a least square parameter estimation method, and determining whether the measured value of the DPF differential pressure sensor is credible based on the third parameter set.
The invention also provides a system for determining the reliability of the DPF differential pressure sensor, which comprises the following steps: the DPF differential pressure sensor is used for collecting pressure differences at two ends of the DPF so as to determine the measured value of the DPF differential pressure sensor; an exhaust gas flow value determination module of the exhaust pipe for determining an exhaust gas flow value of the exhaust pipe; and the electronic control unit is used for executing the method for determining the reliability of the DPF differential pressure sensor.
A computer device comprising a memory and a processor, the memory having stored therein computer readable instructions that, when executed by the processor, cause the processor to perform the steps of the method of determining the trustworthiness of the DPF differential pressure sensor described above.
A storage medium storing computer readable instructions that, when executed by one or more processors, cause the one or more processors to perform the steps of the method of determining the trustworthiness of a DPF differential pressure sensor as described above.
According to the method, the system, the equipment and the medium for determining the reliability of the DPF differential pressure sensor, the parameter set corresponding to the linear relation between the measured value of the DPF differential pressure sensor and the exhaust flow value of the exhaust pipe in the current period is determined according to the least square method, and whether the measured value of the DPF differential pressure sensor in the current period is reliable or not is determined according to whether the parameters in the parameter set are in the range corresponding to the parameters under the normal working condition of the DPF differential pressure sensor, so that the reliability of the measured value of the DPF differential pressure sensor is determined based on the actual working condition (the exhaust flow value of the exhaust pipe) in a period of time, and further, the basis is laid for the fault diagnosis of the follow-up DPF differential pressure sensor. And the exhaust flow value in the first set is judged to meet the preset condition, and the effective first set is selected to determine the linear relation and the parameter set, so that the determined linear relation and the parameter set are closer to the linear relation and the parameter value of the parameter set in the actual application scene, and whether the measured value of the DPF differential pressure sensor is reliable or not is conveniently determined according to accuracy, and whether the measured value of the DPF differential pressure sensor has deviation or not is determined.
Drawings
FIG. 1 is a schematic diagram of a framework of a system for determining the trustworthiness of a DPF differential pressure sensor provided in one embodiment;
FIG. 2 is one of the flow diagrams of the method for determining the reliability of the DPF differential pressure sensor provided in one embodiment;
FIG. 3 is a second flow chart of a method for determining the reliability of a DPF differential pressure sensor provided in one embodiment;
FIG. 4 is a third flow chart of a method for determining the reliability of a DPF differential pressure sensor provided in one embodiment;
FIG. 5 is a graphical representation of DPF differential pressure sensor measurements (differential pressure) for a DPF differential pressure sensor provided in one embodiment under normal operation;
FIG. 6 is a schematic diagram of a volumetric flow rate curve of a DPF differential pressure sensor provided in one embodiment under normal operation;
FIG. 7A is a graph showing a second coefficient over time for an engine DPF differential pressure sensor provided in one embodiment under normal operation;
FIG. 7B is a graphical representation of a second intercept parameter versus time for an engine DPF differential pressure sensor provided in one embodiment under normal operation;
FIG. 8A is a graph showing a second coefficient over time for a DPF differential pressure sensor measurement provided in one embodiment;
FIG. 8B is a graphical representation of the second intercept parameter over time with a deviation in DPF differential pressure sensor measurements provided in one embodiment.
Detailed Description
The present invention will be described in further detail with reference to the drawings and examples, in order to make the objects, technical solutions and advantages of the present invention more apparent. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the invention.
It is to be noted that unless otherwise defined, technical or scientific terms used herein should be taken in a general sense as understood by one of ordinary skill in the art to which the present invention belongs. The terms "first," "second," and the like, as used herein, do not denote any order, quantity, or importance, but rather are used to distinguish one element from another. The word "comprising" or "comprises", and the like, means that elements or items preceding the word are included in the element or item listed after the word and equivalents thereof, but does not exclude other elements or items. The terms "connected" or "connected," and the like, are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "upper", "lower", "left", "right", etc. are used merely to indicate relative positional relationships, which may also be changed when the absolute position of the object to be described is changed.
For ease of understanding, the technical terms to which the present invention relates will be explained first.
A diesel particulate trap (Diesel particulate filter, DPF) for reducing particulate emissions in diesel exhaust pollutants. During operation of the diesel particulate filter, particulate matter may be deposited within the filter, resulting in an increase in exhaust backpressure. The pressure across the DPF is typically monitored by a DPF differential pressure sensor to identify the trapped particulate matter in the DPF. When the differential pressure between two ends of the DPF reaches a certain limit value, the particles are considered to be trapped too much, a regeneration request is triggered, the trapped particles are oxidized, and the capability of trapping the particles of the DPF is obtained again.
The method, system, apparatus and medium for determining the reliability of a DPF differential pressure sensor of the present invention are described below with reference to the accompanying drawings.
FIG. 1 is a system for determining the reliability of a DPF differential pressure sensor provided by the invention, comprising: the DPF differential pressure sensor 110 is used for collecting pressure differences at two ends of the DPF to determine a measured value of the DPF differential pressure sensor; an exhaust pipe exhaust flow value determination module 120 for determining an exhaust pipe exhaust flow value; the electronic control unit 130 is configured to execute the method for determining the reliability of the DPF differential pressure sensor provided by the present invention.
As shown in fig. 2, in one embodiment, a method of determining the reliability of a DPF differential pressure sensor is proposed, which may be performed by an electronic control unit. The electronic control unit may be an electronic control unit on an automobile or a ship. Specifically, as shown in fig. 2, the method for determining the reliability of the DPF differential pressure sensor provided by the present invention may include the following steps:
step 210, after engine start, obtains a first set of exhaust flow values for the exhaust pipe during the current period and a second set of DPF differential pressure sensor measurements during the current period.
The exhaust gas flow value may be an exhaust gas volume flow value and an exhaust gas mass flow value, among others.
It can be appreciated that the problem of low diagnostic accuracy arises from the use of transient conditions to determine if there is a deviation in the DPF differential pressure sensor measurements. Thus, in the present invention, a first set of exhaust flow values of the exhaust pipe over a period of time (current period) and a second set of DPF differential pressure sensor measurements over the current period are used to determine whether the DPF differential pressure sensor measurements are authentic, thereby determining whether there is a deviation in the DPF differential pressure sensor measurements.
Step 220, determining a first parameter set corresponding to a linear relationship between a measured value of a DPF differential pressure sensor and an exhaust gas flow value in a current period based on the first set, the second set and a least square parameter estimation method when it is determined that the exhaust gas flow value in the first set meets a preset condition.
The preset condition is used for enabling the linear relation determined based on the first set to approach to the linear relation in the actual scene.
It can be understood that, in the present invention, in order to avoid that the distribution of the exhaust flow values in the first set is too concentrated, so as to affect the determination of the linear relationship, therefore, the exhaust flow values in the first set need to meet a preset condition, if the exhaust flow values in the first set in the current period meet the preset condition, the data in the first set is considered valid, and the first set corresponding to the current period can be used to determine the parameters in the corresponding linear relationship, so as to further determine whether the measurement value of the DPF differential pressure sensor is reliable.
Step 230, determining whether each parameter in the first parameter set is within a preset range.
The preset range is a range corresponding to each parameter in the corresponding second parameter set under the normal working condition of the DPF differential pressure sensor.
It will be appreciated that the corresponding first parameter set determined based on the steps 210 and 220 is within the predetermined range under normal operation of the DPF differential pressure sensor, and the first parameter set is not within the predetermined range under offset of the DPF differential pressure sensor. Specifically, the preset range may refer to the range shown by the corresponding parameter in fig. 7A and 7B.
Step 240, determining that the measured value of the DPF differential pressure sensor is reliable in the case that each parameter in the first parameter set is determined to be within a preset range; or, in the case that any one of the first parameter set is determined not to be within a preset range, determining that the measured value of the DPF differential pressure sensor is not trusted.
According to the method for determining the reliability of the DPF differential pressure sensor, the parameter set corresponding to the linear relation between the measured value of the DPF differential pressure sensor and the exhaust flow value of the exhaust pipe in the current period is determined according to the least square method, and whether the measured value of the DPF differential pressure sensor in the current period is reliable or not is determined according to whether the parameters in the parameter set are in the range corresponding to the parameters under the normal working condition of the DPF differential pressure sensor, so that whether the measured value of the DPF differential pressure sensor is reliable or not is determined based on the actual working condition (the exhaust flow value of the exhaust pipe) in a period of time, and further whether deviation exists in the measured value of the DPF differential pressure sensor is determined more accurately, and a foundation is laid for fault diagnosis of the subsequent DPF differential pressure sensor. And the exhaust flow value in the first set is judged to meet the preset condition, and the effective first set is selected to determine the linear relation and the parameter set, so that the determined linear relation and the parameter set are closer to the linear relation and the parameter value of the parameter set in the actual application scene, and whether the measured value of the DPF differential pressure sensor is reliable or not is conveniently determined according to accuracy, and whether the measured value of the DPF differential pressure sensor has deviation or not is determined.
In one embodiment, the determining that the exhaust flow value in the first set meets a preset condition includes:
and determining that the exhaust flow values in the first set meet a preset condition under the condition that each exhaust flow value in the first set is determined to be larger than a first preset threshold value and the minimum exhaust flow value in the first set is smaller than or equal to a second preset threshold value and the maximum exhaust flow value in the first set is determined to be larger than or equal to a third preset threshold value.
In one embodiment, in the case that the exhaust pipe has an exhaust flow value of a volume flow value, the first preset threshold value is 45m 3 /h to 55m 3 Any number between/h, a second preset threshold value of 195m 3 /h to 205m 3 Any number between/h, a third preset threshold of 595m 3 /h to 605m 3 /hAny number of the two.
Preferably, the first preset threshold is 50m 3 And/h, the second preset threshold is 200m 3 Between/h, a third preset threshold value of 600m 3 /h。
It will be appreciated that in the case of smaller exhaust flow values, further DPF diagnostics generally do not need to be performed in conjunction with DPF differential pressure sensor measurements. Therefore, whether each exhaust flow value in the first set is larger than a first preset threshold value can be judged first, further DPF diagnosis is carried out without combining the measured value of the DPF differential pressure sensor, and waste of calculation resources is reduced. In addition, in order to avoid that the distribution of the exhaust gas flow values in the first set is too concentrated, so that the determination of the linear relation is affected, it is necessary to make the exhaust gas flow values in the first set satisfy a preset condition, that is, the minimum exhaust gas flow value in the first set is smaller than or equal to a second preset threshold value, and the maximum exhaust gas flow value in the first set is greater than or equal to a third preset threshold value, so that the data in the first set is considered valid, and the first set corresponding to the current period can be used for determining the parameters in the corresponding linear relation, so as to further determine whether the measurement value of the DPF differential pressure sensor is reliable.
In one embodiment, as shown in fig. 3, the determining, based on the first set, the second set, and the least squares parameter estimation method, a first parameter set corresponding to a linear relationship between a measured value of the DPF differential pressure sensor and an exhaust gas flow value in a current period includes:
step 310, determining an average of the exhaust flow values in the first set as an average of the independent variables.
Average value of independent variableThe corresponding first expression is: />Wherein (1)>For the average value of the individual exhaust flow values in the first set, x 1 、x 2 、x 3 ……x n For each exhaust flow value in the first set, n is the number of exhaust flow values in the first set.
Step 320, determining an average value of the measured values of each DPF differential pressure sensor in the second set as an average value of the dependent variable.
Mean value of dependent variableThe corresponding second expression is: />Wherein (1)>Y, which is the average value of the measured values of the DPF differential pressure sensors in the second set 1 、y 2 、y 3 ……y n Is the individual DPF differential pressure sensor measurement in the second set.
Step 330, determining a first coefficient before the argument based on each of the exhaust gas flow values in the first set and each of the DPF differential pressure sensor measurements in the second set.
The third expression corresponding to the first coefficient b is:b is the first coefficient before the argument, x i Represents the i-th exhaust flow value, y in the first set i Is the i-th DPF differential pressure sensor measurement in the second set.
Step 340, determining a first intercept parameter based on the average of the independent variables, the average of the dependent variables, and a first coefficient prior to the independent variables.
The fourth expression corresponding to the first intercept parameter a is:based on the first coefficient b and the firstThe intercept parameter a determines a first set of parameters.
In one embodiment, as shown in fig. 4, before the determining whether each parameter in the first parameter set is within a preset range, the method further includes:
step 410, determining a second parameter set of each period under the normal working condition of the DPF differential pressure sensor based on the third set of exhaust flow values of the exhaust pipes corresponding to each period, the fourth set of measurement values of the DPF differential pressure sensor and the least square parameter estimation method.
Wherein the parameters in the second parameter set and the first parameter set are the same. It will be appreciated that the process is similar to that shown in fig. 3, and thus reference is made to the relevant description in fig. 3 above, and will not be repeated here.
Step 420, determining the range of each parameter in the second parameter set of each period based on the second parameter set of each period, and determining the range of each parameter in the second parameter set as a preset range.
In one embodiment, the second parameter set of each period includes a second coefficient before the independent variable of the DPF differential pressure sensor under the normal working condition, and a second intercept parameter, where a range of the second coefficient is a first preset range, a range of the second intercept parameter is a second preset range, and the determining whether each parameter in the first parameter set is in the preset range includes: determining whether the first coefficient is within a first preset range and determining whether the first intercept parameter is within a second preset range.
Wherein the second coefficient corresponds to the first coefficient and the second intercept parameter corresponds to the first intercept parameter.
Specifically, the first preset range and the second preset range may refer to ranges shown by corresponding parameters in fig. 7A and 7B. As can be seen by way of example in conjunction with fig. 7A and 7B, the second coefficient of the DPF differential pressure sensor under normal operation is between the first preset range [0,0.04] and the second intercept parameter is between the second preset range [ -4,4 ].
In one embodiment, the method further comprises: and if the exhaust flow value in the fifth set meets the preset condition, determining a third parameter set corresponding to the linear relation between the measured value of the DPF differential pressure sensor and the exhaust flow value of the exhaust pipe in a preset period based on the fifth set, the sixth set of the measured value of the DPF differential pressure sensor in the next period and a least square parameter estimation method, and determining whether the measured value of the DPF differential pressure sensor is credible based on the third parameter set.
It can be understood that, in practical application, if the distribution of the exhaust gas flow values is relatively concentrated, the linear relationship corresponding to the measured values of the DPF differential pressure sensor is not easily determined, so, in order to determine the linear relationship corresponding to the exhaust gas flow values and the measured values of the DPF differential pressure sensor and the corresponding parameters by adopting the least square parameter estimation method when the first set corresponding to the exhaust gas flow values of the current period does not meet the preset conditions, it is possible to continuously determine whether the fifth set corresponding to the exhaust gas flow values of the next period meets the preset conditions, and in case that the fifth set meets the preset conditions, continuously execute the determining process of the credibility of the measured values of the DPF differential pressure sensor, which can refer to the foregoing process, and is not repeated herein for brevity.
Fig. 5 illustrates DPF differential pressure sensor measurements (differential pressure) under normal engine DPF differential pressure sensor operation. Fig. 6 illustrates a volumetric flow curve for an engine DPF differential pressure sensor under normal operation.
Fig. 7A illustrates a time-dependent profile of a second coefficient (parameter b) of an engine DPF differential pressure sensor under normal operation. As can be seen from fig. 7A, the second coefficient of the DPF differential pressure sensor under normal operation is within the first preset range [0,0.04 ].
Fig. 7B illustrates a second intercept parameter (parameter a) versus time for an engine DPF differential pressure sensor under normal operating conditions. As can be seen in conjunction with FIG. 7B, the second intercept parameter for the engine DPF differential pressure sensor under normal operating conditions is between a second predetermined range [ -4,4 ].
Fig. 8A illustrates a time-dependent curve of the second coefficient (parameter b) in the case of deviation of the measured value of the DPF differential pressure sensor of the engine. As can be seen from fig. 8A, the second coefficient b in the case of deviation of the measured value of the DPF differential pressure sensor is between [ -0.4,0.4], and the fluctuation range is greatly increased compared with the second coefficient in the case of normal operation of the DPF differential pressure sensor in fig. 7A.
Fig. 8B illustrates a time-dependent plot of a second intercept parameter (parameter a) for an engine DPF differential pressure sensor measurement with a bias. As can be seen in conjunction with fig. 8B, the intercept parameter a is between [ -20, 20] and the fluctuation range is greatly increased compared with the intercept parameter under the normal operation of the DPF differential pressure sensor in fig. 7B.
In one embodiment, a computer device is provided, the computer device including a memory, a processor, and a computer program stored on the memory and executable on the processor, the processor implementing the steps corresponding to the following method for determining the trustworthiness of a DPF differential pressure sensor when executing the computer program: after the engine is started, acquiring a first set of exhaust flow values of the exhaust pipe in the current period and a second set of DPF differential pressure sensor measurement values in the current period; under the condition that the exhaust flow value in the first set meets the preset condition, determining a first parameter set corresponding to the linear relation between the DPF differential pressure sensor measured value and the exhaust flow value in the current period based on the first set, the second set and a least square parameter estimation method; determining whether each parameter in the first parameter set is within a preset range; under the condition that each parameter in the first parameter set is determined to be in a preset range, determining that the measured value of the DPF differential pressure sensor is reliable; or, in the case that any one of the first parameter set is determined not to be within a preset range, determining that the measured value of the DPF differential pressure sensor is not trusted.
In another aspect, the present invention also provides a computer program product comprising a computer program stored on a non-transitory computer readable storage medium, the computer program comprising program instructions which, when executed by a computer, are capable of performing the method for determining the reliability of a DPF differential pressure sensor provided by the present invention, wherein the method for determining the reliability of a DPF differential pressure sensor comprises: after the engine is started, acquiring a first set of exhaust flow values of the exhaust pipe in the current period and a second set of DPF differential pressure sensor measurement values in the current period; under the condition that the exhaust flow value in the first set meets the preset condition, determining a first parameter set corresponding to the linear relation between the DPF differential pressure sensor measured value and the exhaust flow value in the current period based on the first set, the second set and a least square parameter estimation method; determining whether each parameter in the first parameter set is within a preset range; under the condition that each parameter in the first parameter set is determined to be in a preset range, determining that the measured value of the DPF differential pressure sensor is reliable; or, in the case that any one of the first parameter set is determined not to be within a preset range, determining that the measured value of the DPF differential pressure sensor is not trusted.
In still another aspect, the present invention further provides a non-transitory computer readable storage medium having stored thereon a computer program, which when executed by a processor, is implemented to perform the method for determining the reliability of a DPF differential pressure sensor provided by the present invention, where the method for determining the reliability of a DPF differential pressure sensor includes: after the engine is started, acquiring a first set of exhaust flow values of the exhaust pipe in the current period and a second set of DPF differential pressure sensor measurement values in the current period; under the condition that the exhaust flow value in the first set meets the preset condition, determining a first parameter set corresponding to the linear relation between the DPF differential pressure sensor measured value and the exhaust flow value in the current period based on the first set, the second set and a least square parameter estimation method; determining whether each parameter in the first parameter set is within a preset range; under the condition that each parameter in the first parameter set is determined to be in a preset range, determining that the measured value of the DPF differential pressure sensor is reliable; or, in the case that any one of the first parameter set is determined not to be within a preset range, determining that the measured value of the DPF differential pressure sensor is not trusted.
The apparatus embodiments described above are merely illustrative, wherein the elements illustrated as separate elements may or may not be physically separate, and the elements shown as elements may or may not be physical elements, may be located in one place, or may be distributed over a plurality of network elements. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of this embodiment. Those of ordinary skill in the art will understand and implement the present invention without undue burden.
From the above description of the embodiments, it will be apparent to those skilled in the art that the embodiments may be implemented by means of software plus necessary general hardware platforms, or of course may be implemented by means of hardware. Based on this understanding, the foregoing technical solution may be embodied essentially or in a part contributing to the prior art in the form of a software product, which may be stored in a computer readable storage medium, such as ROM/RAM, a magnetic disk, an optical disk, etc., including several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute the method described in the respective embodiments or some parts of the embodiments.
Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present invention, and are not limiting; although the invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims (10)

1. A method for determining the trustworthiness of a DPF differential pressure sensor, the method comprising:
after the engine is started, acquiring a first set of exhaust flow values of the exhaust pipe in the current period and a second set of DPF differential pressure sensor measurement values in the current period;
under the condition that the exhaust flow value in the first set meets the preset condition, determining a first parameter set corresponding to the linear relation between the DPF differential pressure sensor measured value and the exhaust flow value in the current period based on the first set, the second set and a least square parameter estimation method;
determining whether each parameter in the first parameter set is within a preset range;
under the condition that each parameter in the first parameter set is determined to be in a preset range, determining that the measured value of the DPF differential pressure sensor is reliable; or, in the case that any one of the first parameter set is determined not to be within a preset range, determining that the measured value of the DPF differential pressure sensor is not trusted.
2. The method for determining the trustworthiness of a DPF differential pressure sensor according to claim 1, wherein determining that the exhaust flow value in the first set meets a preset condition includes:
and determining that the exhaust flow values in the first set meet a preset condition under the condition that each exhaust flow value in the first set is determined to be larger than a first preset threshold value and the minimum exhaust flow value in the first set is smaller than or equal to a second preset threshold value and the maximum exhaust flow value in the first set is determined to be larger than or equal to a third preset threshold value.
3. The method for determining the reliability of a DPF differential pressure sensor according to claim 1, wherein determining a first parameter set corresponding to a linear relationship between a measured value of the DPF differential pressure sensor and an exhaust gas flow value in a current period based on the first set, the second set, and a least squares parameter estimation method comprises:
determining an average of the individual exhaust flow values in the first set as an average of the independent variables;
determining an average value of the measured values of each DPF differential pressure sensor in the second set as an average value of the dependent variable;
determining a first coefficient before the independent variable according to each exhaust flow value in the first set and each DPF differential pressure sensor measurement value in the second set;
a first intercept parameter is determined based on the average of the independent variables, the average of the dependent variables, and a first coefficient before the independent variables.
4. The method for determining the reliability of a DPF differential pressure sensor according to claim 3, wherein the first expression corresponding to the average value of the independent variables is:wherein (1)>For the average value of the individual exhaust flow values in the first set, x 1 、x 1 、x 3 ……x n For each exhaust flow value in the first set, n is the number of exhaust flow values in the first set;
the average value of the dependent variable corresponds to the second expression:wherein (1)>Y, which is the average value of the measured values of the DPF differential pressure sensors in the second set 1 、y 2 、y 3 ……y n For each DPF differential pressure sensor measurement in the second set;
the third expression corresponding to the first coefficient before the argument is:b is the first coefficient before the argument, x i Represents the i-th exhaust flow value, y in the first set i An ith DPF differential pressure sensor measurement in the second set;
the fourth expression corresponding to the first intercept parameter is:a first set of parameters is determined based on the first coefficient b and the first intercept parameter a.
5. The method of determining the trustworthiness of a DPF differential pressure sensor of claim 3, wherein prior to said determining whether each parameter of the first set of parameters is within a preset range, the method further comprises:
determining a second parameter set of each period under the normal working condition of the DPF differential pressure sensor based on a third set of exhaust flow values of the exhaust pipe corresponding to each period, a fourth set of measurement values of the DPF differential pressure sensor and a least square parameter estimation method;
and determining the range of each parameter in the second parameter set of each period based on the second parameter set of each period, and determining the range of each parameter in the second parameter set as a preset range.
6. The method for determining the reliability of a DPF differential pressure sensor according to claim 5, wherein the second parameter set of each cycle includes a second coefficient before an independent variable of the DPF differential pressure sensor in a normal operation condition, and a second intercept parameter, the range of the second coefficient is a first preset range, the range of the second intercept parameter is a second preset range, and the determining whether each parameter in the first parameter set is within the preset range includes:
determining whether the first coefficient is within a first preset range and determining whether the first intercept parameter is within a second preset range.
7. The method of determining the trustworthiness of a DPF differential pressure sensor of claim 1, further comprising:
and if the exhaust flow value in the fifth set meets the preset condition, determining a third parameter set corresponding to the linear relation between the measured value of the DPF differential pressure sensor and the exhaust flow value of the exhaust pipe in a preset period based on the fifth set, the sixth set of the measured value of the DPF differential pressure sensor in the next period and a least square parameter estimation method, and determining whether the measured value of the DPF differential pressure sensor is credible based on the third parameter set.
8. A system for determining the trustworthiness of a DPF differential pressure sensor, comprising:
the DPF differential pressure sensor is used for collecting pressure differences at two ends of the DPF so as to determine the measured value of the DPF differential pressure sensor;
an exhaust gas flow value determination module of the exhaust pipe for determining an exhaust gas flow value of the exhaust pipe;
an electronic control unit for performing the method of determining the trustworthiness of a DPF differential pressure sensor according to any one of claims 1 to 7.
9. A computer device comprising a memory and a processor, the memory having stored therein computer readable instructions, which when executed by the processor, cause the processor to perform the steps of the method of determining the trustworthiness of a DPF differential pressure sensor according to any one of claims 1 to 7.
10. A storage medium storing computer readable instructions which, when executed by one or more processors, cause the one or more processors to perform the steps of a method of determining the trustworthiness of a DPF differential pressure sensor according to any one of claims 1 to 7.
CN202311454211.8A 2023-11-02 2023-11-02 Method, system, equipment and medium for determining reliability of DPF differential pressure sensor Pending CN117740228A (en)

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CN202311454211.8A CN117740228A (en) 2023-11-02 2023-11-02 Method, system, equipment and medium for determining reliability of DPF differential pressure sensor

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