Abnormality detection method for engine system

Abstract

The application provides an abnormality detection method applied to an engine system and belonging to the technical field of engine control, and the method comprises the following steps: performing a detection step in a current driving cycle, specifically comprising the following steps: performing a periodicity checking step of a pressure signal: performing first detection processing on the pressure signal at the inlet of an EGR valve to obtain a pressure maximum time interval array and a pressure minimum time interval array, and determining whether the periodicity of the pressure signal at the inlet of the EGR valve is abnormal according to the pressure maximum time interval array and the pressure minimum time interval array; and performing a fluctuation checking step of the pressure signal: performing second detection processing on the pressure signal at the inlet of the EGR valve, performing at least two different filtering processes on the detection results respectively, obtaining a pressure difference array corresponding to each filtering process according to the filtering results of each filtering process, and determining whether the fluctuation of the pressure signal at the inlet of the EGR valve is abnormal according to all the pressure difference arrays.

Description

Technical Field

[0001] This invention relates to the field of engine control technology, and in particular to an anomaly detection method for engine systems. Background Technology

[0002] Hybrid engines are the mainstream type of engine on the market, and EGR technology is a key technology for achieving high thermal efficiency. The gas pressure on both sides of the EGR valve (inlet and outlet) is a crucial input for EGR rate control, determining the estimation of exhaust gas flow and the accuracy of EGR valve opening control, thus affecting the precision of the EGR rate. Therefore, it is necessary to promptly check whether the EGR valve inlet gas pressure signal is normal to avoid affecting EGR rate control and causing adverse effects on engine performance. Summary of the Invention

[0003] The present invention aims to solve at least one of the technical problems existing in the prior art, and proposes an anomaly detection method for engine systems, as well as the system, electronic equipment and computer-readable medium thereof.

[0004] Firstly, this disclosure provides an anomaly detection method for an engine system, comprising: performing a detection step during the current driving cycle, specifically including:

[0005] The steps for periodically checking the pressure signal are as follows: the pressure signal at the EGR valve inlet is first detected and processed to obtain the corresponding pressure maximum time interval array and pressure minimum time interval array, and based on the pressure maximum time interval array and pressure minimum time interval array, it is determined whether the periodicity of the pressure signal at the EGR valve inlet is abnormal.

[0006] The pressure maximum time interval array contains multiple first elements, and the pressure minimum time interval array contains multiple second elements. The first element is the time interval between the maximum pressure detected at the EGR valve inlet in two adjacent sampling periods, and the second element is the time interval between the minimum pressure detected at the EGR valve inlet in two adjacent sampling periods.

[0007] The steps for checking the pressure signal fluctuation are as follows: perform a second detection process on the pressure signal at the EGR valve inlet and perform at least two different filtering processes on the detection results. Obtain the corresponding pressure difference array based on the filtering results of each filtering process, and determine whether the pressure signal fluctuation at the EGR valve inlet is abnormal based on all the pressure difference arrays.

[0008] The pressure difference array contains multiple third elements, which are the difference between the pressure output value of the later sampling period after corresponding filtering and the pressure output value of the previous sampling period after corresponding filtering.

[0009] In some embodiments, the step of performing a second detection process on the pressure signal at the EGR valve inlet and performing at least two different filtering processes on the detection results, and obtaining the corresponding pressure difference array based on the filtering results of each filtering process, includes:

[0010] The pressure signal at the EGR valve inlet is subjected to a second detection process to obtain the pressure output values ​​of multiple sampling periods output by the pressure sensor at the EGR valve inlet. , n is the number of sampling cycles in the second detection process;

[0011] Pressure output values ​​for multiple sampling periods The filtered pressure values ​​were obtained by applying three different filtering methods. , , , , , The pressure output values ​​for the i-th sampling period are respectively The pressure values ​​were obtained by three different filtering processes, all of which were first-order low-pass filters but with different filter coefficients.

[0012] Based on the filtering results of the three filtering processes, three corresponding pressure difference arrays P1[n], P2[n], and P3[n] are obtained:

[0013]

[0014] in, ;

[0015]

[0016] in, ;

[0017]

[0018] in, .

[0019] In some embodiments, the filter coefficients of the first-order low-pass filter corresponding to the pressure difference array P1[n] are: The filter coefficients for the first-order low-pass filter processing corresponding to the pressure difference array P2[n] are: The filter coefficients for the first-order low-pass filter processing corresponding to the pressure difference array P3[n] are: ;

[0020] When the engine speed change rate is not in a stable state during the second detection process, the filter coefficient... , and The values ​​are preset constants C1, C2, and C3, respectively, where C1, C2, and C3 are all greater than 0 and less than 0.5. At this point, the step of determining whether the pressure signal fluctuation at the EGR valve inlet is abnormal based on the entire pressure difference array includes:

[0021] From the three pressure difference arrays P1[n], P2[n], and P3[n], count the total number of values ​​of i that satisfy any of the following conditions, Q3;

[0022] Condition 1a. >0、 <0、 <0, and Greater than or equal to the preset threshold ;

[0023] Condition 2a <0、 >0、 >0, and Greater than or equal to the preset threshold ;

[0024] Condition 3a >0、 >0、 <0, and Greater than or equal to the preset threshold ;

[0025] Condition 4a <0、 <0、 >0, and Greater than or equal to the preset threshold ;

[0026]

[0027]

[0028] The total number Q3 is compared with the third preset threshold CNT3; when Q3 > CNT3, abnormal pressure signal fluctuation at the EGR valve inlet is detected; when Q3 ≤ CNT3, normal pressure signal fluctuation at the EGR valve inlet is detected.

[0029] When the engine speed change rate is stable during the second detection process, the filter coefficient... , and The values ​​are respectively , , C4, C5, and C6 are all greater than 0 and less than 0.5; at this time, the step of determining whether the pressure signal fluctuation at the EGR valve inlet is abnormal based on the entire pressure difference array includes:

[0030] Count the total number of values ​​of i that satisfy any of the following conditions from the three pressure difference arrays P1[n], P2[n] and P3[n];

[0031] Condition 1b >0、 <0、 <0, and Greater than or equal to the preset threshold ;

[0032] Condition 2b <0、 >0、 >0, and Greater than or equal to the preset threshold ;

[0033] Condition 3b >0、 >0、 <0, and Greater than or equal to the preset threshold ;

[0034] Condition 4b <0、 <0、 >0, and Greater than or equal to the preset threshold ;

[0035]

[0036]

[0037] The total number Q4 is compared with the fourth preset threshold CNT4; when Q4 > CNT4, the pressure signal fluctuation at the EGR valve inlet is detected to be abnormal; when Q4 ≤ CNT4, the pressure signal fluctuation at the EGR valve inlet is detected to be normal.

[0038] in, This represents the average value of the target EGR rate of the engine system during the second detection process. This represents the average engine speed during the second detection process. The default speed is pre-calibrated. , , , These are the pre-defined basic calibration threshold values. and All are not greater than and Any one of them.

[0039] In some embodiments, the step of checking pressure signal fluctuations, and before the step of performing the second detection processing on the pressure signal at the EGR valve inlet, further includes: a pre-fluctuation monitoring step, specifically including:

[0040] The opening of the mixing valve in the engine control system is maintained at its maximum value;

[0041] Monitor the overall engine system to ensure it is operating normally, and monitor the EGR subsystem within the engine system to ensure it is operating stably.

[0042] When the engine system as a whole is in normal operation and the EGR subsystem is in stable operation for a continuous period of time t2 within the current monitoring cycle, the second detection and processing step of the pressure signal at the EGR valve inlet is executed.

[0043] If the engine system as a whole is in normal operation and the EGR subsystem is in stable operation for a continuous period of less than the preset time t2, and the opening of the EGR valve remains stable throughout the current monitoring cycle, then the preset time t2 is initialized to the preset initial value, and the detection steps in the current driving cycle end.

[0044] If the engine system as a whole is in normal operation and the EGR subsystem is in stable operation for a continuous period of less than the preset time t2, and the opening of the EGR valve has been unstable during the current monitoring cycle, then the preset time t2 is updated by adding the preset step time to the preset time t2, and the detection step in the current driving cycle ends.

[0045] In some embodiments, the step of determining whether the periodicity of the pressure signal at the EGR valve inlet is abnormal based on the pressure maximum value time interval array and the pressure minimum value time interval array includes:

[0046] When the engine speed change rate is not stable during the first detection process, the total number of elements Q1_MAX in the maximum pressure time interval array whose values ​​are less than the first reference time interval value T1 is counted, and the total number of elements Q1_MIN in the minimum pressure time interval array whose values ​​are less than the first reference time interval value T1 is counted. The first reference time interval value T1 is:

[0047]

[0048] The total number of elements Q1_MAX and Q1_MIN are compared with a first preset threshold CNT1. If at least one of Q1_MAX and Q1_MIN is greater than CNT1, a periodic abnormality in the pressure signal at the EGR valve inlet is detected. If both Q1_MAX and Q1_MIN are less than or equal to CNT1, a periodic normality in the pressure signal at the EGR valve inlet is detected.

[0049] When the engine speed change rate is stable during the first detection process, the total number of elements Q2_MAX in the maximum pressure time interval array whose values ​​are less than the second reference time interval value T2 is counted, and the total number of elements Q2_MIN in the minimum pressure time interval array whose values ​​are less than the second reference time interval value T2 is counted. The second reference time interval value T2 is:

[0050]

[0051] The total number of elements Q2_MAX and Q2_MIN are compared with a second preset threshold CNT2. If at least one of Q2_MAX and Q2_MIN is greater than CNT2, a periodic abnormality in the pressure signal at the EGR valve inlet is detected. If both Q2_MAX and Q2_MIN are less than or equal to CNT2, a periodic normality in the pressure signal at the EGR valve inlet is detected.

[0052] in, This represents the average value of the target EGR rate of the engine system during the first detection and processing step. This represents the average engine speed during the first detection process. This represents the average temperature at the EGR valve inlet during the first detection process. The default speed is pre-calibrated. The default temperature at the EGR valve inlet is pre-calibrated. This is the first preset adjustment coefficient. The second preset adjustment coefficient is d0~d2 and d3~d5 are the preset calibration durations, and d2≥d5, d1≥d4, and d0≥d3.

[0053] In some embodiments, before the steps of comparing the total number of elements Q1_MAX and the total number of elements Q1_MIN with the first preset number of times threshold CNT1, the method further includes:

[0054] The steps for determining the first preset threshold number CNT1 include:

[0055] When the EGR valve is closed during the first detection process, the absolute value of the average fresh air intake flow rate into the cylinder during the first detection process is used as the basis. Compared to the pre-defined default traffic ratio The ratio is determined using the first mapping process. The corresponding first preset number threshold CNT1;

[0056] When the EGR valve is not closed during the first detection process, the absolute value of the average fresh air intake flow rate into the cylinder during the first detection process is used as the basis. Compared to the pre-defined default traffic ratio The ratio was determined using the second mapping process. The corresponding first preset number threshold CNT1;

[0057] Among them, the first preset number threshold CNT1 determined based on the first mapping process or the second mapping process and the ratio They are positively correlated, and for the same ratio The first preset number threshold determined by the first mapping process is less than or equal to the first preset number threshold determined by the second mapping process;

[0058] And / or, before the step of comparing the total number of elements Q2_MAX and the total number of elements Q2_MIN with the second preset threshold CNT2, the method further includes:

[0059] The steps for determining the second preset threshold number CNT2 include:

[0060] When the EGR valve is closed during the first detection process, the absolute value of the average fresh air intake flow rate into the cylinder during the first detection process is used as the basis. Compared to the pre-defined default traffic ratio The ratio was determined using a third mapping process. The corresponding second preset threshold number of times, CNT2;

[0061] When the EGR valve is not closed during the first detection process, the absolute value of the average fresh air intake flow rate into the cylinder during the first detection process is used as the basis. Compared to the pre-defined default traffic ratio The ratio was determined using the fourth mapping process. The corresponding second preset threshold number of times, CNT2;

[0062] Among them, the second preset number threshold CNT2 determined based on the third or fourth mapping process and the ratio They are positively correlated, and for the same ratio The second preset number threshold determined by the third mapping process is less than or equal to the second preset number threshold determined by the fourth mapping process.

[0063] In some embodiments, after the step of periodically checking the pressure signal, the method further includes:

[0064] When the periodic pressure signal at the EGR valve inlet is determined to be periodically abnormal during the periodic pressure signal verification step, the first preset counting parameter is adjusted. Second preset counting parameters All values ​​are initialized to 0;

[0065] When the pressure signal at the EGR valve inlet is determined to be periodically normal during the periodic pressure signal verification step, the first preset counting parameter is adjusted based on the performance of the engine speed change rate during the periodic pressure signal verification process. Second preset counting parameters At least one of them shall be updated; wherein, if at least once during the step of periodically checking the pressure signal, the engine speed change rate is not in a stable state, then the first preset counting parameter shall be updated. Increment by 1; if the engine speed change rate is found to be stable at least once during the periodic check of the pressure signal, then increment the second preset count parameter. Add 1;

[0066] Determine the first preset counting parameter Second preset counting parameters Does it meet one of the following conditions:

[0067] Condition 1c Equal to the first preset counting threshold G1 and If G is equal to 0, then G1 ≥ 3;

[0068] Condition 2c Equal to the second preset counting threshold G2 and If G equals 0, then G2 ≥ 2;

[0069] Condition 3c and Both are not 0 and their sum equals the third preset counting threshold G3, where G3 ≥ 3;

[0070] If satisfied, proceed with the step of checking the fluctuation of the pressure signal, and set the first preset counting parameter. Second preset counting parameters All values ​​are initialized to 0; if this condition is not met, the system proceeds normally to the next detection step in the driving cycle.

[0071] In some embodiments, after the pressure signal volatility verification step, the method further includes:

[0072] Detect whether the step of periodically checking pressure signals has been performed during the current driving cycle;

[0073] When it is detected that a step of periodically checking the pressure signal has been performed during the current driving cycle, and the step of checking the pressure signal fluctuation during the current driving cycle determines that the pressure signal fluctuation is abnormal, wait for the abnormal fault to be restored, and then proceed to the detection step in the next driving cycle normally after the abnormal fault is restored.

[0074] If it is detected that the step of periodically checking the pressure signal has been performed in the current driving cycle, and the step of checking the pressure signal fluctuation in the current driving cycle has determined that the pressure signal fluctuation is normal, then the step of periodically checking the pressure signal in the next driving cycle is skipped, and the step of checking the pressure signal fluctuation in the next driving cycle is executed directly.

[0075] If it is detected that the step of periodically checking the pressure signal has not been performed during the current driving cycle, and the step of checking the pressure signal fluctuation during the current driving cycle determines that the pressure signal fluctuation is abnormal, then the first update processing rule is used to adjust the first preset adjustment coefficient. Or the second preset adjustment coefficient Perform an update and wait for the abnormal fault to be resolved, and then proceed to the detection steps in the next driving cycle normally after the abnormal fault is resolved;

[0076] If it is detected that the step of periodically checking the pressure signal has not been performed during the current driving cycle, and the step of checking the pressure signal fluctuation during the current driving cycle determines that the pressure signal fluctuation is normal, then the second update processing rule is used to adjust the first preset adjustment coefficient. Or the second preset adjustment coefficient Perform the update and proceed normally to the next driving cycle's detection steps;

[0077] The first update processing rules include the following:

[0078] If, during the periodic pressure signal verification process, the engine system's operating status is last detected to include: the engine speed change rate being unstable and the EGR valve being open, then the first preset adjustment coefficient will be adjusted. Decrease the first preset step value z1 to perform the update;

[0079] If, during the periodic pressure signal verification process, the last monitored engine system operating status includes: engine speed change rate not being stable and EGR valve being closed, then the first preset adjustment coefficient will be adjusted. Decrease the second preset step value z2 to perform the update;

[0080] If, during the periodic pressure signal verification process, the last monitored state of the engine system includes: the engine speed change rate is stable and the EGR valve is not closed, then the second preset adjustment coefficient will be adjusted. Decrease the third preset step value z3 to perform the update;

[0081] If, during the periodic pressure signal verification process, the engine system's operating status is last detected to include: the engine speed change rate being unstable and the EGR valve being closed, then the second preset adjustment coefficient will be adjusted. Decrease the fourth preset step value z4 to perform the update;

[0082] The second update processing rules include the following:

[0083] If, during the periodic pressure signal verification process, the engine system's operating status is last detected to include: the engine speed change rate being unstable and the EGR valve being open, then the first preset adjustment coefficient will be adjusted. Add the first preset step value z1 to perform the update;

[0084] If, during the periodic pressure signal verification process, the last monitored engine system operating status includes: engine speed change rate not being stable and EGR valve being closed, then the first preset adjustment coefficient will be adjusted. Add a second preset step value z2 to perform the update;

[0085] If, during the periodic pressure signal verification process, the last monitored state of the engine system includes: the engine speed change rate is stable and the EGR valve is not closed, then the second preset adjustment coefficient will be adjusted. Add a third preset step value z3 to perform the update;

[0086] If, during the periodic pressure signal verification process, the engine system's operating status is last detected to include: the engine speed change rate being unstable and the EGR valve being closed, then the second preset adjustment coefficient will be adjusted. Add the fourth preset step value z4 to perform the update;

[0087] Where z1 < z2, z3 < z4, z3 < z1, z4 < z2.

[0088] In some embodiments, the step of performing a first detection process on the pressure signal at the EGR valve inlet and obtaining the corresponding pressure maximum value time interval array and pressure minimum value time interval array includes:

[0089] The pressure signal at the EGR valve inlet is first detected and processed to obtain the maximum and minimum pressure values ​​and the corresponding time points collected by the pressure sensor at the EGR valve inlet in m sampling periods.

[0090] Based on the average engine speed in the first detection process Determine the number M of sampling periods to be excluded, where M is related to... Positively correlated;

[0091] Remove the maximum and minimum pressure values ​​and their corresponding time points from the first M sampling cycles in the first detection process;

[0092] An array of time intervals for maximum pressure is generated based on the time points of the maximum pressure collected in the last mM sampling cycles of the first detection process, and an array of time intervals for minimum pressure is generated based on the time points of the minimum pressure collected in the last mM sampling cycles of the first detection process.

[0093] In some embodiments, the step of performing a first detection process on the pressure signal at the EGR valve inlet to obtain the maximum and minimum pressure values ​​and corresponding time points collected by the pressure sensor at the EGR valve inlet in m sampling periods includes:

[0094] Acquire all raw pressure values ​​obtained by the pressure sensor over m sampling periods;

[0095] All raw pressure data are subjected to a preset first-order low-pass filter to obtain filtered pressure data for m sampling periods. The filter coefficients in the preset first-order low-pass filter process are: :

[0096] Wherein, when the particulate matter trap in the engine system is in active regeneration state during the first detection and processing, the filter coefficient ;

[0097] When the particulate matter filter in the engine system is in a non-active regeneration state during the first detection and processing, the filter coefficient... ;

[0098] and These are two pre-calibrated reference filter coefficients, and , This is the third preset adjustment coefficient. This is the fourth preset adjustment coefficient;

[0099] From the filtered pressure data of m sampling periods, determine the maximum and minimum pressure values ​​and the corresponding time points in each sampling period;

[0100] The first update processing rule is used to adjust the first preset adjustment coefficient. Or the second preset adjustment coefficient The update process also includes: applying the first update processing rule to adjust the third preset adjustment coefficient. Or the fourth preset adjustment coefficient Update;

[0101] The second update processing rule is used to adjust the first preset adjustment coefficient. Or the second preset adjustment coefficient The update process also includes: using a second update processing rule to adjust the third preset adjustment coefficient. Or the fourth preset adjustment coefficient Update;

[0102] The first update processing rules also include the following:

[0103] If, during the periodic pressure signal verification process, the last monitored state of the engine system includes: the engine speed change rate is not stable and the particulate filter is in active regeneration mode, then the third preset adjustment coefficient will be adjusted. Subtract the fifth preset step value z5;

[0104] If, during the periodic pressure signal verification process, the engine system's operating status is last detected as follows: the engine speed change rate is not stable and the particulate filter is in a non-active regeneration state, then the third preset adjustment coefficient will be adjusted. Subtract the sixth preset step value z6, and adjust the fourth preset coefficient. Subtract the seventh preset step value z7;

[0105] If, during the periodic pressure signal verification process, the last monitored state of the engine system includes: a stable engine speed change rate and the particulate filter in active regeneration mode, then the third preset adjustment coefficient will be adjusted. Subtract the eighth preset step value z8;

[0106] If, during the periodic pressure signal verification process, the engine system's operating status is last detected as follows: the engine speed change rate is not stable and the particulate filter is in a non-active regeneration state, then the third preset adjustment coefficient will be adjusted. Subtract the ninth preset step value z9, and adjust the fourth preset adjustment coefficient. Subtract the tenth preset step value z10;

[0107] The second update processing rules also include the following:

[0108] If, during the periodic pressure signal verification process, the last monitored state of the engine system includes: the engine speed change rate is not stable and the particulate filter is in active regeneration mode, then the third preset adjustment coefficient will be adjusted. Add the fifth preset step value z5, and add the eleventh preset step value z11 to the fourth preset adjustment coefficient;

[0109] If, during the periodic pressure signal verification process, the engine system's operating status is last detected as follows: the engine speed change rate is not stable and the particulate filter is in a non-active regeneration state, then the fourth preset adjustment coefficient will be adjusted. Add the seventh preset step value z7;

[0110] If, during the periodic pressure signal verification process, the last monitored state of the engine system includes: a stable engine speed change rate and the particulate filter in active regeneration mode, then the third preset adjustment coefficient will be adjusted. Add the eighth preset step value z8;

[0111] If, during the periodic pressure signal verification process, the engine system's operating status is last detected as follows: the engine speed change rate is not stable and the particulate filter is in a non-active regeneration state, the third preset adjustment coefficient will be adjusted. Add the ninth preset step value z9, and adjust the fourth preset coefficient. Add the tenth preset step value z10;

[0112] Among them, z5 > z6, z5 > z7 > z11, z5 > z8 > z10 > z9.

[0113] Secondly, this disclosure also provides an anomaly detection system for an engine system, which can implement the anomaly detection method for an engine system as provided in the first aspect, and the system includes: a pressure signal periodic verification module and a pressure signal fluctuation verification module.

[0114] The pressure signal periodic verification module is configured to perform a step of periodic verification of pressure signals during a driving cycle; the pressure signal fluctuation verification module is configured to perform a step of fluctuation verification of pressure signals during a driving cycle.

[0115] Thirdly, embodiments of this disclosure provide an electronic device, including:

[0116] One or more processors;

[0117] Memory, used to store one or more programs;

[0118] When the one or more programs are executed by the one or more processors, the one or more processors implement any of the methods provided in the first aspect.

[0119] Fourthly, embodiments of this disclosure provide a computer-readable medium storing a computer program, wherein the computer program, when executed by a processor, implements the steps of any of the methods provided in the first aspect.

[0120] The technical solution disclosed herein, by acquiring the time interval arrays of maximum and minimum pressure values ​​corresponding to the pressure signal at the EGR valve inlet, can effectively determine whether the periodicity of the pressure signal at the EGR valve inlet is abnormal. The periodicity of the pressure signal at the EGR valve inlet can, to a certain extent, reflect whether the pressure sensor used in the differential pressure sensor to determine the inlet air pressure is faulty. Simultaneously, by acquiring at least two different pressure difference arrays obtained after processing the pressure signal at the EGR valve inlet through at least two different filtering methods, it can effectively determine whether the fluctuation of the pressure signal at the EGR valve inlet is abnormal. The fluctuation of the pressure signal at the EGR valve inlet can, to a certain extent, reflect whether the pressure sensor used in the differential pressure sensor to determine the inlet air pressure is faulty. Based on at least one of the processes of periodic pressure signal verification and pressure signal fluctuation verification, this application can promptly and accurately identify when the pressure sensor used in the differential pressure sensor to determine the inlet air pressure malfunctions. Attached Figure Description

[0121] Figure 1 This is a schematic diagram of the engine system involved in the technical solution disclosed herein.

[0122] Figure 2 A flowchart of an anomaly detection method for an engine system provided in this disclosure embodiment;

[0123] Figure 3 A schematic diagram illustrating the processing principle of the anomaly detection method applied to an engine system provided in this embodiment of the disclosure;

[0124] Figure 4 A flowchart illustrating another anomaly detection method for an engine system provided in this disclosure embodiment;

[0125] Figure 5 A flowchart of yet another anomaly detection method applied to an engine system provided in this disclosure embodiment;

[0126] Figure 6 This is a structural block diagram of an electronic device provided in an embodiment of the present invention. Detailed Implementation

[0127] To enable those skilled in the art to better understand the technical solutions of the present invention, exemplary embodiments of the present invention are described below in conjunction with the accompanying drawings, including various details of the embodiments of the present invention to aid understanding. These should be considered merely exemplary. Therefore, those skilled in the art should recognize that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of the present invention. Similarly, for clarity and brevity, descriptions of well-known functions and structures are omitted in the following description.

[0128] Where there is no conflict, the various embodiments of the present invention and the features thereof may be combined with each other.

[0129] As used herein, the term “and / or” includes any and all combinations of one or more related enumerated entries.

[0130] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the invention. As used herein, the singular forms “a” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will also be understood that when the terms “comprising” and / or “made of” are used in this specification, the presence of the stated feature, integral, step, operation, element, and / or component is specified, but the presence or addition of one or more other features, integrals, steps, operations, elements, components, and / or groups thereof is not excluded. Terms such as “connected” or “linked” are not limited to physical or mechanical connections but can include electrical connections, whether direct or indirect.

[0131] Unless otherwise specified, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art. It will also be understood that terms such as those defined in commonly used dictionaries should be interpreted as having the meaning consistent with their meaning in the context of the relevant art and the invention, and will not be interpreted as having an idealized or overly formal meaning unless expressly so defined herein.

[0132] In the technical solution of this invention, the collection, storage, use, processing, transmission, provision, and disclosure of user personal information all comply with relevant laws and regulations and do not violate public order and good morals. The use of user data in this technical solution follows relevant national laws and regulations (e.g., the "Information Security Technology - Personal Information Security Specification"). For example: appropriate measures are taken for personal information access control; restrictions are imposed on the display of personal information; the purpose of using personal information does not exceed the scope of direct or reasonable association; and explicit identity targeting is eliminated when using personal information to avoid precisely locating a specific individual.

[0133] Figure 1 This is a schematic diagram of the engine system involved in the technical solution of this disclosure. Figure 1As shown, an engine system generally includes an air filter 1; a mixing valve 2 connected to the air filter, configured to regulate the pressure at the outlet of the EGR valve 10, increasing the pressure difference across the EGR valve 10, with two airflow passages extending from the mixing valve 2; a compressor 3 connected to one of the airflow passages of the mixing valve 2; a throttle valve 4 connected to the compressor 3, wherein the throttle valve 4 has a boost temperature and pressure sensor at its inlet and an intake air temperature and pressure sensor at its outlet, and the throttle valve 4 body has a position sensor and an actuator; an engine 5 connected to the throttle valve 4, configured to compress fresh air for boosting; a turbine 6 connected to the engine 5, configured to control the opening of the exhaust bypass valve; a catalytic converter 7 connected to the turbine 6; and a gasline particulate filter connected to the catalytic converter 7. Filter (GPF) 8; EGR cooler 9 installed on another airflow path of mixing valve 2, configured to receive and cool the exhaust gas output from particulate filter 8, thereby increasing exhaust gas flow rate; EGR valve 10 connected at one end to EGR cooler 9 and at the other end to mixing valve 2, configured to control the exhaust gas flow rate entering cylinder; temperature sensor 11 installed between EGR valve 10 and EGR cooler 9, configured to detect the exhaust gas temperature entering EGR valve 10; differential pressure sensor 12 connected to EGR valve 10 (including a pressure sensor capable of determining the inlet pressure and a pressure sensor capable of determining the outlet pressure), configured to detect the pressure at the inlet and outlet of EGR valve 10.

[0134] The working state of the mixing valve 2, the particulate filter 8, and the EGR valve 10 directly affects the EGR rate of the entire engine system. Therefore, the mixing valve 2, the particulate filter 8, and the EGR valve 10 together constitute the EGR subsystem within the engine system.

[0135] The first-order low-pass filtering process involved in this disclosure can be expressed by the following formula:

[0136]

[0137] Where X represents the parameter to be filtered. This represents the original value of the parameter X to be filtered obtained in the Nth sampling (i.e., the Nth sampling period). This represents the value of the parameter X to be filtered, obtained from the original value obtained in the (N-1)th sampling (i.e., the (N-1)th sampling period), after being processed by a first-order low-pass filter. This represents the filter coefficient configured for the parameter X to be filtered. This represents the value of the parameter X to be filtered, obtained from the original value obtained in the Nth sampling, after being processed by a first-order low-pass filter. The specific process of the first-order low-pass filter is standard knowledge in this field and will not be elaborated here.

[0138] In this disclosure, the parameter X to be filtered includes, but is not limited to, engine speed. Engine speed change rate (Its acquisition method is the engine speed in the current sampling period) The difference between the engine speed and the previous sampling period, divided by the sampling period. ), Fresh air intake density into the cylinder Throttle opening Mixing valve opening EGR valve opening GPF export pressure EGR valve inlet gas pressure (referred to as EGR valve inlet pressure) Any one of them.

[0139] The filtering coefficients corresponding to the different parameters X to be filtered mentioned above It can be obtained in the following ways:

[0140] 1) Filtering coefficients for engine speed n The method for obtaining it is as follows: Default coefficient Take 0.05.

[0141] exist The conditions are met continuously for a preset time. This indicates that the engine speed is in a stable state (with minimal speed fluctuations). The threshold coefficient is also included. In this example, we use 0.05. This example takes 0.1s.

[0142] 2) Engine speed change rate Filter coefficients The method for obtaining it is as follows: Default coefficient Take 0.05.

[0143] exist The conditions are met continuously for a preset time. This indicates that the engine speed change rate is in a stable state (the speed change rate fluctuates little). The threshold coefficient is also included. In this example, we use 0.05. This example takes 0.1s.

[0144] 3) Intake density of fresh air entering the cylinder Filter coefficients The method for obtaining it is as follows:

[0145] 3.1) If both the engine speed and the rate of change of engine speed are in a steady state, then: (This example) The calibration speed is 1000 rpm. The purpose of this setting is for normalization; at different engine speeds, no special calibration is needed, only calibration of the 4-cylinder engine and the engine at 1000 rpm. (This reduces calibration testing work) The default coefficient for the fresh air intake density entering the cylinder is 1; in this example, it is set to 0.02.

[0146] 3.2) In other cases, , The default coefficient for the fresh air intake density entering the cylinder is two; in this example, it is set to 0.02.

[0147] exist The conditions are met continuously for a preset time. This indicates that the intake air density is in a stable state (with minimal fluctuations). The threshold coefficient is also included. In this example, we use 0.05. This example takes 0.1s.

[0148] 4) Throttle opening Filter coefficients The method for obtaining it is as follows:

[0149] 4.1) If both the engine speed and the rate of change of engine speed are in a steady state, then: (This example) The calibration speed is 1000 rpm. The purpose of this setting is for normalization; at different engine speeds, no special calibration is needed, only calibration of the 4-cylinder engine and the engine at 1000 rpm. (This reduces calibration testing work) Throttle opening The default coefficient is 1; in this example, it is set to 0.02.

[0150] 4.2) Other cases, then , Throttle opening The default coefficient is two; in this example, it is set to 0.02.

[0151] exist The conditions are met continuously for a preset time. This indicates that the throttle opening is in a stable state (throttle fluctuation is small). The threshold coefficient is also mentioned. In this example, the value is 0.01. This example takes 0.1s.

[0152] 5) Mixing valve opening Filter coefficients The method for obtaining it is as follows:

[0153] 5.1) If both the engine speed and the rate of change of engine speed are in a steady state, then: (This example) The calibration speed is 1000 rpm. The purpose of this setting is for normalization; at different engine speeds, no special calibration is needed, only calibration of the 4-cylinder engine and the engine at 1000 rpm. (This reduces calibration testing work) For the opening degree of the mixing valve The default coefficient is 1; in this example, it is set to 0.02.

[0154] 5.2) In other cases, , For the opening degree of the mixing valve The default coefficient is two; in this example, it is set to 0.02.

[0155] exist The conditions are met continuously for a preset time. This indicates that the mixing valve opening is in a stable state (the mixing valve fluctuates little). The threshold coefficient is also mentioned. In this example, the value is 0.01. This example takes 0.1s.

[0156] 6) EGR valve opening Filter coefficients The method for obtaining it is as follows:

[0157] 6.1) If both the engine speed and the rate of change of engine speed are in a steady state, then: (This example) The calibration speed is 1000 rpm. The purpose of this setting is for normalization; at different engine speeds, no special calibration is needed, only calibration of the 4-cylinder engine and the engine at 1000 rpm. (This reduces calibration testing work) EGR valve opening The default coefficient is 1; in this example, it is set to 0.02.

[0158] 6.2) Other cases, then , EGR valve opening The default coefficient is two; in this example, it is set to 0.02.

[0159] exist The conditions are met continuously for a preset time. This indicates that the EGR valve opening is in a stable state (the EGR valve fluctuation is small). The threshold coefficient is also mentioned. In this example, the value is 0.01. This example takes 0.1s.

[0160] 7) GPF export pressure Filter coefficients The method for obtaining it is as follows:

[0161] 7.1) If both the engine speed and the rate of change of engine speed are in a steady state, then: (This example) The calibration speed is 1000 rpm. The purpose of this setting is for normalization; at different engine speeds, no special calibration is needed, only calibration of the 4-cylinder engine and the engine at 1000 rpm. (This reduces calibration testing work) The default coefficient for GPF outlet pressure is 1; in this example, it is set to 0.2.

[0162] 7.2) Other situations, GPF outlet pressure default coefficient two Take 0.2. The filtering coefficient should be no less than the filtering coefficients for engine speed, engine speed change rate, fresh air intake density, throttle opening, and mixing valve opening. These factors are used to verify the EGR inlet pressure, requiring stable operating conditions. Therefore, their filtering coefficients need to be relatively small. However, the GPF outlet pressure filtering coefficient should not be too small; otherwise, excessive smoothing will result in an overly smooth EGR valve inlet pressure, potentially leading to incorrect assessments of EGR pressure. The purpose of GPF filtering is to prevent excessive fluctuations in EGR inlet pressure caused by exhaust flow disturbances, which could make it impossible to determine if the pressure signal is abnormal.

[0163] 8) EGR valve inlet pressure Filter coefficients The method for obtaining it is as follows:

[0164] 8.1) If both the engine speed and the rate of change of engine speed are in a steady state, then: (This example) The calibration speed is 1000 rpm. The purpose of this setting is for normalization; at different engine speeds, no special calibration is needed, only calibration of the 4-cylinder engine and the engine at 1000 rpm. (This reduces calibration testing work) The default coefficient for the EGR valve inlet pressure is 1; in this example, it is set to 0.2.

[0165] 8.2) Other situations, The default inlet pressure coefficient for the EGR valve is two. Take 0.2. The filtering coefficient should not be less than the filtering coefficient of engine speed, engine speed change rate, fresh air intake density entering the cylinder, throttle opening, and mixing valve opening. This is because engine speed, engine speed change rate, fresh air intake density entering the cylinder, throttle opening, and mixing valve opening are used as conditions for checking the EGR inlet pressure. These conditions require stable operating conditions, so it is necessary to ensure that the EGR is in a stable state. Therefore, the filtering coefficient should be relatively small. However, the filtering coefficient of the EGR valve inlet pressure should not be too small, otherwise it may lead to an incorrect evaluation of whether the EGR pressure is normal.

[0166] In practical applications, the methods for determining the filter coefficients for different parameters X are not limited to the examples above; they can also be calibrated or adjusted manually.

[0167] Furthermore, the foregoing description of whether the detection parameter X is in a stable state is only one optional implementation scheme in this disclosure and does not limit the technical solution of this disclosure. In practical applications, it is possible to determine whether "a certain parameter is in a stable state" based on some existing detection methods, or to set reasonable judgment conditions according to actual needs to detect whether "a certain parameter is in a stable state". The technical solution of this disclosure does not limit this.

[0168] Figure 2 This is a flowchart illustrating an anomaly detection method applied to an engine system, provided as an embodiment of this disclosure. Figure 2 As shown, this anomaly detection method applied to engine systems can detect anomalies in the EGR valve inlet pressure signal. The method includes: performing a detection step during the current driving cycle, specifically including:

[0169] Step Sa, the step of periodically checking the pressure signal, includes: performing a first detection process on the pressure signal at the EGR valve inlet and obtaining the corresponding pressure maximum time interval array and pressure minimum time interval array, and determining whether the pressure signal at the EGR valve inlet is periodically abnormal based on the pressure maximum time interval array and pressure minimum time interval array.

[0170] The maximum pressure time interval array contains multiple first elements, and the minimum pressure time interval array contains multiple second elements. The first element is the time interval between the maximum pressure detected at the EGR valve inlet in two adjacent sampling periods, and the second element is the time interval between the minimum pressure detected at the EGR valve inlet in two adjacent sampling periods.

[0171] Step Sb, the step of checking the pressure signal fluctuation; includes: performing a second detection process on the pressure signal at the EGR valve inlet and performing at least two different filtering processes on the detection results, obtaining the corresponding pressure difference array based on the filtering results of each filtering process, and determining whether the pressure signal fluctuation at the EGR valve inlet is abnormal based on the total pressure difference array.

[0172] The pressure difference array contains multiple third elements, which are the difference between the pressure output value of the later sampling period after corresponding filtering and the pressure output value of the previous sampling period after corresponding filtering.

[0173] The technical solution disclosed herein, by acquiring the time interval arrays of maximum and minimum pressure values ​​corresponding to the pressure signal at the EGR valve inlet, can effectively determine whether the periodicity of the pressure signal at the EGR valve inlet is abnormal. The periodicity of the pressure signal at the EGR valve inlet can, to a certain extent, reflect whether the pressure sensor used in the differential pressure sensor to determine the inlet air pressure is faulty. Simultaneously, by acquiring at least two different pressure difference arrays obtained after processing the pressure signal at the EGR valve inlet through at least two different filtering methods, it can effectively determine whether the fluctuation of the pressure signal at the EGR valve inlet is abnormal. The fluctuation of the pressure signal at the EGR valve inlet can, to a certain extent, reflect whether the pressure sensor used in the differential pressure sensor to determine the inlet air pressure is faulty. Based on at least one of the processes of periodic pressure signal verification and pressure signal fluctuation verification, this application can promptly and accurately identify when the pressure sensor used in the differential pressure sensor to determine the inlet air pressure malfunctions.

[0174] Figure 3 This is a schematic diagram illustrating the processing principle of the anomaly detection method applied to an engine system provided in this embodiment of the disclosure. Figure 3 As shown, step Sa, which involves periodically checking the pressure signal, specifically includes two parts: step Sa01 and step Sa02.

[0175] Among them, step Sa01, the pre-monitoring step of periodic verification, specifically includes: monitoring whether the engine system as a whole is in normal operating condition according to the monitoring cycle, and monitoring whether the EGR subsystem part of the engine system is in stable operating condition.

[0176] In this disclosure, step Sa02 will only be executed if step Sa01 detects that the engine system as a whole is in normal operating condition and the EGR subsystem within the engine system is in stable operating condition. If step Sa01 detects that the engine system as a whole is not in normal operating condition or the EGR subsystem within the engine system is in unstable operating condition, the abnormal detection process for the EGR valve inlet pressure signal in this driving cycle will end directly, and the process will wait to enter the abnormal detection process for the EGR valve inlet pressure signal in the next driving cycle.

[0177] Step Sa02, Periodic Verification of Formal Processing Steps; Specifically, this includes: performing a first detection process on the pressure signal at the EGR valve inlet and obtaining the corresponding pressure maximum time interval array and pressure minimum time interval array, and determining whether the pressure signal at the EGR valve inlet is periodically abnormal based on the pressure maximum time interval array and pressure minimum time interval array.

[0178] After entering step Sa02, step Sa01 will continue to be executed in parallel for monitoring. When it is detected that the engine system as a whole is not operating normally or that the EGR subsystem within the engine system is in an unstable operating state, step Sa02 will also stop executing. The abnormal detection process of the EGR valve inlet pressure signal in this driving cycle will end directly (indicated as no fault was detected), and wait for the abnormal detection process of the EGR valve inlet pressure signal in the next driving cycle.

[0179] In step Sa01, whether the engine system as a whole is in normal operating condition can be determined based on the following conditions:

[0180] (1) The engine is running.

[0181] (2) The engine speed is within a certain range, in this example it is between 600rpm and 5900rpm, and the engine speed after entering the EGR system pressure check enters a stable state (the detection method described above can be used).

[0182] (3) The intake density of fresh air entering the cylinder is within a certain range. In this example, it is between 200 mgpl and 3000 mgpl, and the intake density after entering the EGR system pressure check enters a stable state (the detection method described above can be used).

[0183] (4) Throttle opening It enters a stable state (the detection method described above can be used).

[0184] (5) The engine boost control closed loop state remains unchanged (that is, if the boost closed loop state has been entered, the boost closed loop state must be maintained; if the closed loop state has not been entered, the boost closed loop state should not be entered).

[0185] (6) The fluctuation of the target air-fuel ratio of the engine (the difference between the target air-fuel ratios of two adjacent sampling periods) is within a certain range, which is ±0.1 in this example.

[0186] (7) The difference between the target air-fuel ratio and the actual air-fuel ratio of the engine fluctuates within a certain range (the difference between the target air-fuel ratio and the actual air-fuel ratio in two adjacent sampling periods). In this example, it is ±0.1.

[0187] (8) The actual air-fuel ratio fluctuation of the engine (the difference between the actual air-fuel ratios of two adjacent sampling periods) is within a certain range, and in this example, it is ±0.1.

[0188] (9) The engine coolant temperature is within a certain range (0℃ to 100℃ in this example), and the engine coolant temperature fluctuation after entering the EGR system pressure check (the difference between the engine coolant temperatures of two adjacent sampling periods) is small. In this example, ±2℃ is taken.

[0189] (10) The engine intake temperature is within a certain range (30℃ to 80℃ in this example), and the intake temperature fluctuation after entering the EGR system pressure check (the difference between the intake temperatures of two adjacent sampling cycles) is small. In this example, it is ±1.5℃.

[0190] (11) The fluctuation of engine ignition angle efficiency (the difference between the ignition angle efficiency of two adjacent sampling periods) is small, and in this example, it is taken as ±0.1.

[0191] (12) The engine did not experience knocking or pre-ignition.

[0192] (13) The engine did not experience fuel cut-off.

[0193] (14) Both the oxygen sensor before the catalyst and the oxygen sensor after the catalyst have been activated by heating.

[0194] (15) The atmospheric pressure fluctuation (the difference in atmospheric pressure between two adjacent sampling periods) is small, and in this example, it is ±0.5 kPa.

[0195] (16) No misfire occurred in the engine system.

[0196] (17) No pressure signal fault was detected in the engine system.

[0197] If all 17 conditions above are met within the monitoring cycle (which can be pre-designed according to actual needs; in this embodiment, it is set to 6 seconds), and the duration of meeting the conditions exceeds a preset time t0 (t0 is less than the monitoring cycle), then the engine system can be detected as being in normal operation. Conversely, if none of the conditions are met, the engine system is detected as being in abnormal operation, and the abnormal detection process for the EGR valve inlet pressure signal in this driving cycle ends directly, waiting to enter the abnormal detection process for the EGR valve inlet pressure signal in the next driving cycle.

[0198] Of course, in practical applications, the judgment conditions can be reduced or increased according to actual needs to monitor whether the engine system is in normal operating condition. Existing monitoring methods can also be used to monitor whether the engine system is in normal operating condition. The technical solution disclosed herein does not limit the specific means of monitoring whether the engine system is in normal operating condition.

[0199] After confirming that the engine system as a whole is operating normally, the next step is to monitor whether the EGR subsystem within the engine system is operating stably. The stability of the EGR subsystem can be determined based on the following conditions:

[0200] (1) The opening of the mixing valve reaches a stable state (the detection method described above can be used).

[0201] (2) The target EGR rate fluctuation (the difference between the target EGR rates of two adjacent sampling periods) is within a certain range, which is ±0.02 in this example.

[0202] (3) The EGR valve opening is in a stable state (the detection method described above can be used).

[0203] (4) The EGR valve inlet temperature fluctuation (the difference between the EGR valve inlet temperatures of two adjacent sampling periods) is small, and in this example, it is ±3℃.

[0204] (5) The state of the particle trap has not changed (either in active regeneration state or inactive regeneration state).

[0205] (6) The outlet pressure fluctuation of the particulate filter is small, that is, it satisfies:

[0206] exist The conditions are met continuously for a preset time. This indicates that the outlet pressure of the particulate filter is in a stable state. The threshold coefficient is also mentioned. In this example, the value is 0.01. This example uses 0.05s.

[0207] (7) No EGR valve inlet pressure sensor circuit failure (including any circuit failure such as open circuit or short circuit) occurred.

[0208] If all seven conditions above are met and the duration of these conditions exceeds a preset time t1, the EGR subsystem can be considered to be in a stable operating state, and the process proceeds to step Sa02. Conversely, if none of these conditions are met, the entire engine system is considered to be in an abnormal operating state, and the abnormal detection process for the EGR valve inlet pressure signal in this driving cycle ends directly, awaiting the start of the abnormal detection process for the EGR valve inlet pressure signal in the next driving cycle.

[0209] The method for obtaining t1 is as follows:

[0210] 1) If the EGR valve is closed, then t1 is the time it takes for the exhaust gas to flow from the GPF outlet to the EGR valve inlet, plus N1*. The time it takes for exhaust gas to flow from the GPF outlet to the EGR valve inlet can be obtained through bench calibration. Specifically, bench calibration can fix the engine speed and the intake air density into the cylinder, and close the EGR valve. The time is obtained by sampling various data sources. In subsequent applications, the average value of the filtered engine speed, the average value of the intake air density into the cylinder, and the average value of the EGR valve opening during the most recent period when the engine system was operating normally will be used instead of the fixed engine speed and intake air density during bench calibration. This will determine the time it takes for exhaust gas to flow from the GPF outlet to the EGR valve inlet under the latest stable operating conditions (the period during the most recent period when the engine system was operating normally). Add N1* to this time. Let t1 be the delay number. N1 is determined by the average value of the engine speed filter value during the most recent monitoring of the engine system as a whole in normal operation. The larger the average value of the engine speed filter value, the larger N1 needs to be set in order to ensure stable operating conditions and the accuracy of pressure signal verification.

[0211] Table 1. Correspondence between the average value of the engine speed after filtering and N1

[0212]

[0213] Based on the average value of the engine speed after filtering during the most recent monitoring of the engine system as a whole under normal operation, the interval in Table 1 is determined, and then the corresponding N1 is found according to the interval.

[0214] 2) If the EGR valve is closed, then t1 is the time it takes for the exhaust gas to flow from the GPF outlet to the EGR valve inlet, plus N2*. The time it takes for exhaust gas to flow from the GPF outlet to the EGR valve inlet can be obtained through bench calibration. Specifically, bench calibration can fix the engine speed and the intake air density into the cylinder, and close the EGR valve. The time is obtained by sampling various data sources. In subsequent applications, the average value of the filtered engine speed, the average value of the intake air density into the cylinder, and the average value of the EGR valve opening during the most recent period when the engine system was operating normally will be used instead of the fixed engine speed and intake air density during bench calibration. This will determine the time it takes for exhaust gas to flow from the GPF outlet to the EGR valve inlet under the latest stable operating conditions (the period during the most recent period when the engine system was operating normally). Add N2* to this time. As t1. N2 is the second delay number. N2 is determined by the average value of the engine speed filter value and the average value of the EGR valve opening during the most recent monitoring of the engine system as a whole in normal operation. The larger the average value of the engine speed filter value, the larger N2 needs to be set in order to ensure stable operating conditions and the accuracy of pressure signal verification.

[0215] Table 2. Correspondence between the average value of engine speed after filtering, the average value of EGR valve opening, and N2.

[0216]

[0217] Based on the average value of the engine speed after filtering and the average value of the EGR valve opening during the most recent monitoring of the engine system as a whole under normal operation, the intervals in Table 2 are determined for both, and then the corresponding N2 is found based on the intervals in which they are located.

[0218] Of course, in this disclosure, t1 can also be a value pre-calibrated manually. This disclosure does not limit the setting of t1.

[0219] In step Sa02, the step of performing a first detection process on the pressure signal at the EGR valve inlet and obtaining the corresponding pressure maximum value time interval array and pressure minimum value time interval array can be implemented as follows: First, perform a first detection process on the pressure signal at the EGR valve inlet to obtain the pressure maximum and minimum values ​​collected by the pressure sensor at the EGR valve inlet in m sampling cycles and the corresponding time points; based on the average engine speed in the first detection process... Determine the number M of sampling periods to be excluded, where M is related to... Positive correlation; remove the maximum and minimum pressure values ​​and corresponding time points from the first M sampling cycles in the first detection process; generate a pressure maximum value time interval array based on the time points of the maximum pressure values ​​collected in the last mM sampling cycles in the first detection process, and generate a pressure minimum value time interval array based on the time points of the minimum pressure values ​​collected in the last mM sampling cycles in the first detection process.

[0220] In this disclosure, considering that the signal may be unstable in the early stage of step Sa02, which may affect the accuracy of pressure signal detection, it is necessary to first remove the maximum and minimum pressure values ​​of the previous M sampling cycles.

[0221] It should be noted that the number of sampling periods m in the first detection process can be preset according to actual needs; for example, m can be 50. The "positive correlation" in this disclosure can be a linear positive correlation or a stepwise positive correlation.

[0222] Table 3. Correspondence between the average value of the engine speed after filtering and M.

[0223]

[0224] Based on the average engine speed in the first detection process (the engine system as a whole is in normal operating condition and the EGR subsystem within the engine system is in stable operating condition). We determine the interval in Table 3, and then query the corresponding M based on the interval.

[0225] The step of performing a first detection and processing on the pressure signal at the EGR valve inlet to obtain the maximum and minimum pressure values ​​and corresponding time points collected by the pressure sensor in m sampling periods can be implemented as follows: First, acquire all the raw pressure value data obtained by the pressure sensor in m sampling periods; then, perform a preset first-order low-pass filter on all the raw pressure value data to obtain the filtered pressure value data for m sampling periods. The preset filter coefficient in the first-order low-pass filter process is... Among them, when the particulate matter filter in the engine system is in active regeneration mode during the first detection and processing, the filter coefficient... When the particulate matter filter in the engine system is in a non-active regeneration state during the first detection and processing, the filter coefficient... ; and These are two pre-calibrated reference filter coefficients, and , This is the third preset adjustment coefficient. The fourth preset adjustment coefficient is used; finally, the maximum and minimum pressure values ​​and the corresponding time points in each sampling period are determined from the filtered pressure value data of m sampling periods.

[0226] In step Sa02, the step of determining whether the periodicity of the pressure signal at the EGR valve inlet is abnormal based on the pressure maximum value time interval array and the pressure minimum value time interval array can be achieved using the following method:

[0227] 1) When the engine speed change rate is not stable during the first detection process, the total number of elements in the statistical pressure maximum value time interval array whose value is less than the first reference time interval value T1 is Q1_MAX, and the total number of elements in the statistical pressure minimum value time interval array whose value is less than the first reference time interval value T1 is Q1_MIN. The first reference time interval value T1 is:

[0228]

[0229] The total number of elements Q1_MAX and Q1_MIN are compared with the first preset threshold CNT1. When at least one of Q1_MAX and Q1_MIN is greater than CNT1, a periodic abnormality in the pressure signal at the EGR valve inlet is detected. When both Q1_MAX and Q1_MIN are less than or equal to CNT1, a periodic normality in the pressure signal at the EGR valve inlet is detected.

[0230] 2) When the engine speed change rate is stable during the first detection process, the total number of elements in the statistical pressure maximum value time interval array whose value is less than the second reference time interval value T2 is Q2_MAX, and the total number of elements in the statistical pressure minimum value time interval array whose value is less than the second reference time interval value T2 is Q2_MIN. The second reference time interval value T2 is:

[0231]

[0232] The total number of elements Q2_MAX and Q2_MIN are compared with the second preset threshold CNT2. If at least one of Q2_MAX and Q2_MIN is greater than CNT2, an abnormal periodicity of the pressure signal at the EGR valve inlet is detected. If both Q2_MAX and Q2_MIN are less than or equal to CNT2, the periodicity of the pressure signal at the EGR valve inlet is detected as normal.

[0233] in, This represents the average value of the target EGR rate of the engine system during the first detection and processing step. This represents the average engine speed during the first detection process. This represents the average temperature at the EGR valve inlet during the first detection process. The default speed is pre-calibrated (1000 rpm in this example). The default temperature at the EGR valve inlet is pre-calibrated (550℃ in this example). This is the first preset adjustment coefficient. The second preset adjustment coefficient is d0~d2 and d3~d5 are the preset calibration durations, and d2≥d5, d1≥d4, and d0≥d3.

[0234] d0~d2 and d3~d5 are in different The values ​​are obtained by fitting data from faulty and non-faulty pressure sensors. As an example, d0, d1, and d2 are 10.5 ms, 1.2 ms, and 50 ms, respectively; d3, d4, and d5 are 30 ms, 0.9 ms, and 9.2 ms, respectively.

[0235] In some embodiments, before comparing the total number of elements Q1_MAX and the total number of elements Q1_MIN with the first preset count threshold CNT1, the method further includes: determining the first preset count threshold CNT1. This can be determined using the following method:

[0236] 1) When the EGR valve is closed during the first detection process, the absolute value of the average fresh air intake flow rate into the cylinder during the first detection process is used as the basis. Compared to the pre-defined default traffic (The ratio of 10 g / s in this example) The ratio is determined using the first mapping process. The corresponding first preset number threshold CNT1.

[0237] 2) When the EGR valve is not closed during the first detection process, the absolute value of the average fresh air intake flow rate into the cylinder during the first detection process is used. Compared to the pre-defined default traffic ratio The ratio was determined using the second mapping process. The corresponding first preset number threshold CNT1.

[0238] Among them, the first preset number threshold CNT1 determined based on the first mapping process or the second mapping process and the ratio There is a positive correlation (the larger the absolute value of the intake airflow, the greater the flow disturbance in the exhaust system may be), and for the same ratio... The first preset number of times threshold determined by the first mapping process is less than or equal to the first preset number of times threshold determined by the second mapping process. A specific example will be given below.

[0239] Table 4. Ratio of EGR valve to values ​​used during the first mapping process when the EGR valve is closed. Correspondence table of the first preset number of times threshold CNT1

[0240]

[0241] Table 5. Ratio when the EGR valve used in the second mapping process is in the closed state Correspondence table of the first preset number of times threshold CNT1

[0242]

[0243] Based on whether the EGR valve is in a closed or open state during the first detection process, the ratio is determined by referring to Table 4 (first mapping process) or Table 5 (second mapping process). The interval in which it is located is then used to determine the size of the corresponding first preset threshold number CNT1.

[0244] Similarly, before comparing the total number of elements Q2_MAX and Q2_MIN with the second preset count threshold CNT2, the method further includes: determining the second preset count threshold CNT2. This can be determined using the following method:

[0245] 1) When the EGR valve is closed during the first detection process, the absolute value of the average fresh air intake flow rate into the cylinder during the first detection process is used as the basis. Compared to the pre-defined default traffic ratio The ratio was determined using a third mapping process. The corresponding second preset number threshold CNT2.

[0246] 2) When the EGR valve is not closed during the first detection process, the absolute value of the average fresh air intake flow rate into the cylinder during the first detection process is used. Compared to the pre-defined default traffic ratio The ratio was determined using the fourth mapping process. The corresponding second preset number threshold CNT2.

[0247] Among them, the second preset number threshold CNT2 determined based on the third or fourth mapping process and the ratio There is a positive correlation (the larger the absolute value of the intake airflow, the greater the flow disturbance in the exhaust system may be), and for the same ratio... The second preset number threshold determined by the third mapping process is less than or equal to the second preset number threshold determined by the fourth mapping process.

[0248] Table 6. Ratio of EGR valve to value when it is closed during the third mapping process Correspondence table of the second preset number of times threshold CNT2

[0249]

[0250] Table 7. Ratio when the EGR valve used in the fourth mapping process is in the closed state Correspondence table of the second preset number of times threshold CNT2

[0251]

[0252] Based on whether the EGR valve is in a closed or open state during the first detection process, the ratio is determined by referring to Table 6 (third mapping process) or Table 7 (fourth mapping process). The interval in which it is located is then used to determine the size of the corresponding second preset threshold number CNT2.

[0253] In some embodiments, step Sb, which performs pressure signal fluctuation verification, includes two parts: step Sb01 and step Sb02.

[0254] Among them, step Sb01, the pre-monitoring step for volatility verification, specifically includes: maintaining the opening of the mixing valve in the engine system at its maximum value, monitoring whether the engine system as a whole is in normal operation according to the monitoring cycle, and monitoring whether the EGR subsystem in the engine system is in stable operation.

[0255] It should be noted that the execution process of step Sb01 is similar to that of step Sa01, but the condition (1) designed for monitoring whether the engine system as a whole is in normal operation during the monitoring cycle should not only be designed as "the mixing valve opening enters a stable state" but also be limited to "the mixing valve opening maintains its maximum value". The specific monitoring process will not be described in detail here.

[0256] When the engine system as a whole is in normal operation and the EGR subsystem is in stable operation for a continuous period of time within the current monitoring cycle, step Sb02 is executed.

[0257] If the engine system as a whole is found to be operating normally and the EGR subsystem is in a stable operating state for a continuous period of less than the preset time t2, and the opening of the EGR valve remains stable throughout the current monitoring cycle, then the preset time t2 is initialized to the preset initial value. In this driving cycle, the abnormal detection process for the EGR valve inlet pressure signal ends directly, and the process waits to enter the next driving cycle for the abnormal detection process for the EGR valve inlet pressure signal.

[0258] If the engine system as a whole is in normal operation and the EGR subsystem is in stable operation for less than the preset time t2 is maintained during the current monitoring cycle, and the opening of the EGR valve has been unstable during the current monitoring cycle, then the preset time t2 is updated by adding a preset step time (e.g., 0.05s). The abnormal detection process for the EGR valve inlet pressure signal in this driving cycle ends directly, and the process waits to enter the abnormal detection process for the EGR valve inlet pressure signal in the next driving cycle.

[0259] In this disclosure, the purpose of dynamically adjusting t2 is to avoid misjudgment caused by EGR valve opening fluctuations in pressure fluctuation verification.

[0260] In this disclosure, step Sb02 will only be executed if step Sb01 detects that the engine system as a whole is in normal operating condition and the EGR subsystem within the engine system is in stable operating condition. If step Sb01 detects that the engine system as a whole is not in normal operating condition or the EGR subsystem within the engine system is in unstable operating condition, the abnormal detection process for the EGR valve inlet pressure signal in this driving cycle will end directly, and the process will wait to enter the abnormal detection process for the EGR valve inlet pressure signal in the next driving cycle.

[0261] Step Sb02, formal processing steps for fluctuation verification; specifically including: performing a second detection processing on the pressure signal at the EGR valve inlet and performing at least two different filtering processing on the detection results, obtaining the corresponding pressure difference array based on the filtering results of each filtering processing, and determining whether the pressure signal fluctuation at the EGR valve inlet is abnormal based on the total pressure difference array.

[0262] After entering step Sb02, step Sb01 will continue to be executed in parallel for monitoring. When it is detected that the engine system as a whole is not operating normally or that the EGR subsystem within the engine system is in an unstable operating state, step Sb02 will also stop executing. The abnormal detection process of the EGR valve inlet pressure signal in this driving cycle will end directly (indicated as no fault was detected), and wait for the abnormal detection process of the EGR valve inlet pressure signal in the next driving cycle.

[0263] In step Sb02, the step of performing a second detection process on the pressure signal at the EGR valve inlet and performing at least two different filtering processes on the detection results, and obtaining the corresponding pressure difference array based on the filtering results of each filtering process, can be implemented as follows: First, perform a second detection process on the pressure signal at the EGR valve inlet to obtain the pressure output values ​​of multiple sampling periods output by the pressure sensor at the EGR valve inlet. , n represents the number of sampling cycles in the second detection process; then, the pressure output value for multiple sampling cycles... The filtered pressure values ​​were obtained by applying three different filtering methods. , , , , , The pressure output values ​​for the i-th sampling period are respectively Pressure values ​​were obtained using three different filtering processes, all of which were first-order low-pass filters with different filter coefficients. Finally, based on the filtering results of the three processes, three corresponding pressure difference arrays P1[n], P2[n], and P3[n] were obtained:

[0264]

[0265] in, .

[0266]

[0267] in, .

[0268]

[0269] in, .

[0270] In some embodiments, the filter coefficients of the first-order low-pass filter corresponding to the pressure difference array P1[n] are: The filter coefficients for the first-order low-pass filter processing corresponding to the pressure difference array P2[n] are: The filter coefficients for the first-order low-pass filter processing corresponding to the pressure difference array P3[n] are: ;

[0271] Depending on whether the engine speed change rate is in a stable or unstable state during the second detection process, this disclosure designs corresponding processing schemes for each:

[0272] 1) When the engine speed change rate is not in a stable state during the second detection process, the filter coefficient... , and The values ​​are preset constants C1, C2, and C3, respectively, where C1, C2, and C3 are all greater than 0 and less than 0.5; as an example, C1, C2, and C3 are 0.2, 0.1, and 0.05, respectively.

[0273] At this point, the steps to determine whether the pressure signal fluctuation at the EGR valve inlet is abnormal based on the complete pressure difference array include:

[0274] First, count the total number of values ​​of i that satisfy any of the following conditions from the three pressure difference arrays P1[n], P2[n] and P3[n].

[0275] Condition 1a. >0、 <0、 <0, and Greater than or equal to the preset threshold .

[0276] Condition 2a <0、 >0、 >0, and Greater than or equal to the preset threshold .

[0277] Condition 3a >0、 >0、 <0, and Greater than or equal to the preset threshold .

[0278] Condition 4a <0、 <0、 >0, and Greater than or equal to the preset threshold .

[0279]

[0280]

[0281] Then, the total number Q3 is compared with the third preset count threshold CNT3. If Q3 > CNT3, abnormal pressure signal fluctuation at the EGR valve inlet is detected; if Q3 ≤ CNT3, normal pressure signal fluctuation at the EGR valve inlet is detected. In this disclosure, the third preset count threshold CNT3 can be pre-designed and adjusted according to actual needs; for example, CNT3 can be set to 30.

[0282] 2) When the engine speed change rate is in a stable state during the second detection process, the filter coefficient... , and The values ​​are respectively , , C4, C5, and C6 are all greater than 0 and less than 0.5; as an example, C4, C5, and C6 take values ​​of 0.2, 0.1, and 0.05, respectively.

[0283] At this point, the steps to determine whether the pressure signal fluctuation at the EGR valve inlet is abnormal based on the complete pressure difference array include:

[0284] Count the total number of values ​​of i that satisfy any of the following conditions from the three pressure difference arrays P1[n], P2[n] and P3[n].

[0285] Condition 1b >0、 <0、 <0, and Greater than or equal to the preset threshold .

[0286] Condition 2b <0、 >0、 >0, and Greater than or equal to the preset threshold .

[0287] Condition 3b >0、 >0、 <0, and Greater than or equal to the preset threshold .

[0288] Condition 4b <0、 <0、 >0, and Greater than or equal to the preset threshold .

[0289]

[0290]

[0291] The total number Q4 is compared with the fourth preset count threshold CNT4. If Q4 > CNT4, abnormal pressure signal fluctuation at the EGR valve inlet is detected; if Q4 ≤ CNT4, normal pressure signal fluctuation at the EGR valve inlet is detected. In this disclosure, the fourth preset count threshold CNT4 can be pre-designed and adjusted according to actual needs; for example, CNT4 can be set to 20.

[0292] in, This represents the average value of the target EGR rate of the engine system during the second detection process. This represents the average engine speed during the second detection process. The default speed is pre-calibrated (1000 rpm in this example). , , , These are the pre-defined basic calibration threshold values. and All are not greater than and Any one of them. As an example, and All values ​​are 0.23. and All values ​​are 0.18.

[0293] Figure 4 A flowchart illustrating another anomaly detection method applied to an engine system, provided as an embodiment of this disclosure. Figure 4 As shown, Figure 4 The method shown includes not only steps Sa and Sb in the previous embodiments, but also steps S1 and S2 between steps Sa and Sb.

[0294] Step S1: Adjust the first preset counting parameter Second preset counting parameters .

[0295] In step S1, when a periodic anomaly in the pressure signal at the EGR valve inlet is determined during the periodic pressure signal verification step, the first preset counting parameter is set... Second preset counting parameters All values ​​are initialized to 0.

[0296] When the pressure signal at the EGR valve inlet is determined to be periodically normal during the periodic pressure signal verification step, the first preset counting parameter is adjusted based on the engine speed change rate during the periodic pressure signal verification process. Second preset counting parameters At least one of them shall be updated; wherein, if at least once during the step of periodically checking the pressure signal, the engine speed change rate is not in a stable state, then the first preset counting parameter shall be updated. Add 1 (even if the engine speed change rate is not in a stable state after multiple monitoring, in step S1) (Only one increment is performed); if the engine speed change rate is found to be stable at least once during the periodic pressure signal check, then the second preset counting parameter is incremented. Increment by 1 (even if the engine speed change rate is repeatedly monitored to be in a stable state, in step S1) It only performs one increment operation.

[0297] It should be noted that if, during the periodic verification of pressure signals, the engine speed change rate is detected to be stable at least once and unstable at least once, then... and All are incremented by 1.

[0298] Step S2: Determine the first preset counting parameter Second preset counting parameters Does it meet one of the following conditions:

[0299] Condition 1c Equal to the first preset counting threshold G1 and If G is equal to 0, then G1 ≥ 3.

[0300] Condition 2c Equal to the second preset counting threshold G2 and If G equals 0, then G2≥2.

[0301] Condition 3c and Both are not 0 and their sum equals the third preset counting threshold G3, where G3≥3.

[0302] If satisfied, proceed to step Sb to check the fluctuation of the pressure signal, and set the first preset counting parameter. Second preset counting parameters All values ​​are initialized to 0; if this condition is not met, the detection step of the current driving cycle ends, and the system proceeds normally to the detection step of the next driving cycle.

[0303] Figure 5 This is a flowchart illustrating yet another anomaly detection method applied to an engine system, provided as an embodiment of this disclosure. Figure 5 As shown, in some embodiments, after step Sb, steps S3 to S5 are also included.

[0304] Step S3: Detect whether the step of periodically checking the pressure signal has been performed during the current driving cycle.

[0305] When it is detected that a step of periodically checking the pressure signal has been performed during the current driving cycle, and the step of checking the pressure signal fluctuation during the current driving cycle determines that the pressure signal fluctuation is abnormal, wait for the abnormal fault to be resolved, and then proceed to the detection step in the next driving cycle normally after the abnormal fault is resolved.

[0306] If it is detected that a step of periodically checking the pressure signal has been performed in the current driving cycle, and the step of checking the pressure signal fluctuation in the current driving cycle has determined that the pressure signal fluctuation is normal, then the step of periodically checking the pressure signal in the next driving cycle is skipped, and the step of checking the pressure signal fluctuation in the next driving cycle is executed directly.

[0307] If it is detected that the step of periodically checking the pressure signal has not been performed during the current driving cycle, and the step of checking the pressure signal fluctuation during the current driving cycle determines that the pressure signal fluctuation is abnormal, then step S4 is executed.

[0308] If it is detected that the step of periodically checking the pressure signal has not been performed during the current driving cycle, and the step of checking the pressure signal fluctuation during the current driving cycle determines that the pressure signal fluctuation is normal, then step S5 is executed.

[0309] Step S4: Apply the first update processing rule to the first preset adjustment coefficient. Or the second preset adjustment coefficient Update.

[0310] After step S4 is completed, wait for the abnormal fault to be resolved, and then proceed to the detection steps in the next driving cycle normally after the abnormal fault is resolved.

[0311] Step S5: Use the second update processing rule to adjust the first preset adjustment coefficient. Or the second preset adjustment coefficient Update.

[0312] After step S5 is completed, the normal driving cycle will proceed to the next detection step.

[0313] The first update processing rules include the following:

[0314] If, during the periodic pressure signal verification process, the engine system's operating status is last detected to include: the engine speed change rate being unstable and the EGR valve being open, then the first preset adjustment coefficient will be adjusted. The first preset step value z1 is reduced (0.04 in this embodiment) to perform the update.

[0315] If, during the periodic pressure signal verification process, the last monitored engine system operating status includes: engine speed change rate not being stable and EGR valve being closed, then the first preset adjustment coefficient will be adjusted. The second preset step value z2 is reduced (0.05 in this embodiment) to perform the update.

[0316] If, during the periodic pressure signal verification process, the last monitored state of the engine system includes: the engine speed change rate is stable and the EGR valve is not closed, then the second preset adjustment coefficient will be adjusted. The third preset step value z3 (0.03 in this embodiment) is reduced to perform the update.

[0317] If, during the periodic pressure signal verification process, the engine system's operating status is last detected to include: the engine speed change rate being unstable and the EGR valve being closed, then the second preset adjustment coefficient will be adjusted. The fourth preset step value z4 (0.04 in this embodiment) is reduced to perform the update.

[0318] The second update processing rules include the following:

[0319] If, during the periodic pressure signal verification process, the engine system's operating status is last detected to include: the engine speed change rate being unstable and the EGR valve being open, then the first preset adjustment coefficient will be adjusted. Add a first preset step value z1 (0.04 in this embodiment) to perform the update.

[0320] If, during the periodic pressure signal verification process, the last monitored engine system operating status includes: engine speed change rate not being stable and EGR valve being closed, then the first preset adjustment coefficient will be adjusted. Add a second preset step value z2 (0.05 in this embodiment) to perform the update.

[0321] If, during the periodic pressure signal verification process, the last monitored state of the engine system includes: the engine speed change rate is stable and the EGR valve is not closed, then the second preset adjustment coefficient will be adjusted. A third preset step value z3 (0.03 in this embodiment) is added for updating.

[0322] If, during the periodic pressure signal verification process, the engine system's operating status is last detected to include: the engine speed change rate being unstable and the EGR valve being closed, then the second preset adjustment coefficient will be adjusted. A fourth preset step value z4 (0.04 in this embodiment) is added for updating.

[0323] In the above settings, z1 < z2, z3 < z4, z3 < z1, z4 < z2.

[0324] In some embodiments, a first update processing rule is used to adjust the first preset adjustment coefficient. Or the second preset adjustment coefficient The update process also includes: applying the first update processing rule to adjust the third preset adjustment coefficient. Or the fourth preset adjustment coefficient Update.

[0325] The second update processing rule is used to adjust the first preset adjustment coefficient. Or the second preset adjustment coefficient The update process also includes: using a second update processing rule to adjust the third preset adjustment coefficient. Or the fourth preset adjustment coefficient Update.

[0326] The first update processing rules also include the following:

[0327] If, during the periodic pressure signal verification process, the last monitored state of the engine system includes: the engine speed change rate is not stable and the particulate filter is in active regeneration mode, then the third preset adjustment coefficient will be adjusted. Subtract the fifth preset step value z5 (0.05 in this embodiment).

[0328] If, during the periodic pressure signal verification process, the engine system's operating status is last detected as follows: the engine speed change rate is not stable and the particulate filter is in a non-active regeneration state, then the third preset adjustment coefficient will be adjusted. Subtract the sixth preset step value z6 (0.01 in this embodiment), and then adjust the fourth preset adjustment coefficient. Subtract the seventh preset step value z7 (0.03 in this embodiment); at this point, since faults are prone to occur, there is no need for overly smooth filtering, thus improving the diagnostic speed. Similarly, if a fault occurs during the non-active regeneration process of the GPF, it is also necessary to appropriately reduce the filtering during the active regeneration process (active regeneration is more prone to faults than non-active regeneration) to improve the diagnostic speed.

[0329] If, during the periodic pressure signal verification process, the last monitored state of the engine system includes: a stable engine speed change rate and the particulate filter in active regeneration mode, then the third preset adjustment coefficient will be adjusted. Subtract the eighth preset step value z8 (0.04 in this embodiment).

[0330] If, during the periodic pressure signal verification process, the engine system's operating status is last detected as follows: the engine speed change rate is not stable and the particulate filter is in a non-active regeneration state, then the third preset adjustment coefficient will be adjusted. Subtract the ninth preset step value z9 (0.01 in this embodiment), and then adjust the fourth preset adjustment coefficient. Subtract the tenth preset step value z10 (0.03 in this embodiment).

[0331] The second update processing rules also include the following:

[0332] If, during the periodic pressure signal verification process, the last monitored state of the engine system includes: the engine speed change rate is not stable and the particulate filter is in active regeneration mode, then the third preset adjustment coefficient will be adjusted. Add the fifth preset step value z5 (0.05 in this embodiment), and add the fourth preset adjustment coefficient to the eleventh preset step value z11 (0.01 in this embodiment).

[0333] If, during the periodic pressure signal verification process, the engine system's operating status is last detected as follows: the engine speed change rate is not stable and the particulate filter is in a non-active regeneration state, then the fourth preset adjustment coefficient will be adjusted. Adding the seventh preset step value z7 (0.03 in this embodiment); at this point, faults are very unlikely to occur, so the appropriate filtering becomes smoother, avoiding misdiagnosis. At the same time, if faults are not likely to occur during the active regeneration process of the GPF, it is also necessary to appropriately increase the filtering during the non-active regeneration process (non-active regeneration is less likely to cause faults than active regeneration) to improve the diagnostic speed.

[0334] If, during the periodic pressure signal verification process, the last monitored state of the engine system includes: a stable engine speed change rate and the particulate filter in active regeneration mode, then the third preset adjustment coefficient will be adjusted. Add the eighth preset step value z8 (0.04 in this embodiment).

[0335] If, during the periodic pressure signal verification process, the engine system's operating status is last detected as follows: the engine speed change rate is not stable and the particulate filter is in a non-active regeneration state, the third preset adjustment coefficient will be adjusted. Adding the ninth preset step value z9 (0.01 in this embodiment), the fourth preset adjustment coefficient is... In this embodiment, the tenth preset step value z10 is added (0.03).

[0336] In the above settings, z5 > z6, z5 > z7 > z11, z5 > z8 > z10 > z9.

[0337] First preset adjustment coefficient Second preset adjustment coefficient Third preset adjustment coefficient Fourth preset adjustment coefficient The initial value can be designed to be 0. Based on the aforementioned first and second update processing rules, the first preset adjustment coefficient can be adjusted according to the operating conditions of the engine system. Second preset adjustment coefficient Third preset adjustment coefficient Fourth preset adjustment coefficient Make dynamic adjustments.

[0338] The aforementioned first preset adjustment coefficient Second preset adjustment coefficient Third preset adjustment coefficient Fourth preset adjustment coefficient These are all used to adjust and correct the corresponding parameters, and their values ​​can be automatically changed using the schemes mentioned above. Of course, they can also be manually calibrated to fixed values ​​as needed. This disclosure does not impose any limitations on this.

[0339] The technical solution disclosed herein performs secondary filtering of the EGR valve inlet pressure signal based on the EGR valve inlet pressure characteristics. At the same time, it checks and judges the periodicity and volatility of the EGR inlet pressure according to whether the EGR valve is closed or not, and the engine speed fluctuation, thereby improving the accuracy of pressure fault checking and timely avoiding the impact on the EGR rate control accuracy.

[0340] Furthermore, in this disclosure, periodic diagnostics do not interfere with the normal control of the engine. Instead, fluctuation check diagnostics are performed proactively after no fault is detected, which improves fault detection efficiency and avoids interfering with the normal performance control of the engine as much as possible. Moreover, during the diagnostic process, the periodic check threshold and the EGR valve inlet pressure filter coefficient are learned and updated based on the fluctuation check results, which improves diagnostic accuracy and speed.

[0341] Based on the same inventive concept, this disclosure also provides an anomaly detection system for an engine system. This anomaly detection system for an engine system can realize the anomaly detection method for an engine system provided in the previous embodiments. The system includes: a pressure signal periodic verification module and a pressure signal fluctuation verification module.

[0342] The pressure signal periodic verification module is configured to perform a step of periodic verification of pressure signals during a driving cycle; the pressure signal fluctuation verification module is configured to perform a step of fluctuation verification of pressure signals during a driving cycle.

[0343] For a detailed description of the above functional modules, please refer to the corresponding content in the previous embodiments, which will not be repeated here.

[0344] Furthermore, it should be noted that during each driving cycle, depending on the circumstances, the step of performing periodic pressure signal checks may be executed only, or the step of performing pressure signal fluctuation checks may be executed only, or the step of performing periodic pressure signal checks may be executed first and then the step of performing pressure signal fluctuation checks. For the specific execution logic, please refer to the relevant descriptions in the preceding embodiments.

[0345] Based on the same inventive concept, embodiments of the present invention also provide an electronic device. Figure 6 This is a structural block diagram of an electronic device provided in an embodiment of the present invention. Figure 6 As shown, an embodiment of the present invention provides an electronic device including: one or more processors 101, a memory 102, and one or more I / O interfaces 103. The memory 102 stores one or more programs, which, when executed by the one or more processors, cause the one or more processors to implement any of the anomaly detection methods applied to an engine system as described in the above embodiments; the one or more I / O interfaces 103 are connected between the processor and the memory, configured to enable information interaction between the processor and the memory.

[0346] The processor 101 is a device with data processing capabilities, including but not limited to a central processing unit (CPU); the memory 102 is a device with data storage capabilities, including but not limited to random access memory (RAM, more specifically SDRAM, DDR, etc.), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), and flash memory (FLASH); the I / O interface (read / write interface) 103 is connected between the processor 101 and the memory 102, and can realize information interaction between the processor 101 and the memory 102, including but not limited to a data bus (Bus).

[0347] In some embodiments, the processor 101, memory 102, and I / O interface 103 are interconnected via bus 104, and thus connected to other components of the computing device.

[0348] In some embodiments, the one or more processors 101 include a field-programmable gate array.

[0349] This invention also provides a computer-readable medium. The computer-readable medium stores a computer program, which, when executed by a processor, implements the steps of any of the anomaly detection methods applied to an engine system described above. The computer-readable storage medium can be volatile or non-volatile.

[0350] This invention also provides a computer program product, including computer-readable code, or a non-volatile computer-readable storage medium carrying computer-readable code. When the computer-readable code is run in the processor of an electronic device, the processor in the electronic device executes the above-described anomaly detection method applied to an engine system.

[0351] Those skilled in the art will understand that all or some of the steps, systems, and apparatuses disclosed above, and their functional modules / units, can be implemented as software, firmware, hardware, or suitable combinations thereof. In hardware implementations, the division between functional modules / units mentioned above does not necessarily correspond to the division of physical components; for example, a physical component may have multiple functions, or a function or step may be performed collaboratively by several physical components. Some or all physical components may be implemented as software executed by a processor, such as a central processing unit, digital signal processor, or microprocessor, or as hardware, or as an integrated circuit, such as an application-specific integrated circuit (ASIC). Such software can be distributed on a computer-readable storage medium, which may include computer storage media (or non-transitory media) and communication media (or transient media).

[0352] As is known to those skilled in the art, the term computer storage medium includes volatile and non-volatile, removable and non-removable media implemented in any method or technology for storing information, such as computer-readable program instructions, data structures, program modules, or other data. Computer storage media includes, but is not limited to, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM), static random access memory (SRAM), flash memory or other memory technologies, portable compact disc read-only memory (CD-ROM), digital versatile disc (DVD) or other optical disc storage, magnetic cartridges, magnetic tape, disk storage or other magnetic storage devices, or any other medium that can be used to store desired information and is accessible to a computer. Furthermore, it is known to those skilled in the art that communication media typically contain computer-readable program instructions, data structures, program modules, or other data in modulated data signals such as carrier waves or other transmission mechanisms, and may include any information delivery medium.

[0353] The computer-readable program instructions described herein can be downloaded from computer-readable storage media to various computing / processing devices, or downloaded via a network, such as the Internet, local area network, wide area network, and / or wireless network, to an external computer or external storage device. The network may include copper transmission cables, fiber optic transmission, wireless transmission, routers, firewalls, switches, gateway computers, and / or edge servers. A network adapter card or network interface in each computing / processing device receives the computer-readable program instructions from the network and forwards them to the computer-readable storage media in the respective computing / processing device.

[0354] The computer program instructions used to perform the operations of this invention may be assembly instructions, instruction set architecture (ISA) instructions, machine instructions, machine-dependent instructions, microcode, firmware instructions, state setting data, or source code or object code written in any combination of one or more programming languages, including object-oriented programming languages ​​such as Smalltalk, C++, etc., and conventional procedural programming languages ​​such as the "C" language or similar programming languages. The computer-readable program instructions may be executed entirely on the user's computer, partially on the user's computer, as a standalone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving a remote computer, the remote computer may be connected to the user's computer via any type of network—including a local area network (LAN) or a wide area network (WAN)—or may be connected to an external computer (e.g., via the Internet using an Internet service provider). In some embodiments, electronic circuitry, such as programmable logic circuitry, field-programmable gate arrays (FPGAs), or programmable logic arrays (PLAs), is personalized by utilizing state information from the computer-readable program instructions. This electronic circuitry can execute the computer-readable program instructions to implement various aspects of the invention.

[0355] The computer program product described herein can be implemented specifically through hardware, software, or a combination thereof. In one alternative embodiment, the computer program product is specifically embodied in a computer storage medium; in another alternative embodiment, the computer program product is specifically embodied in a software product, such as a software development kit (SDK), etc.

[0356] Various aspects of the present invention are described herein with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It should be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer-readable program instructions.

[0357] These computer-readable program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing apparatus to produce a machine such that, when executed by the processor of the computer or other programmable data processing apparatus, they create means for implementing the functions / actions specified in one or more blocks of the flowchart and / or block diagram. These computer-readable program instructions can also be stored in a computer-readable storage medium that causes a computer, programmable data processing apparatus, and / or other device to operate in a particular manner; thus, the computer-readable medium storing the instructions comprises an article of manufacture that includes instructions for implementing aspects of the functions / actions specified in one or more blocks of the flowchart and / or block diagram.

[0358] Computer-readable program instructions may also be loaded onto a computer, other programmable data processing apparatus, or other device to cause a series of operational steps to be performed on the computer, other programmable data processing apparatus, or other device to produce a computer-implemented process, thereby causing the instructions executed on the computer, other programmable data processing apparatus, or other device to perform the functions / actions specified in one or more boxes of a flowchart and / or block diagram.

[0359] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of the present invention. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of an instruction, which contains one or more executable instructions for implementing a specified logical function. In some alternative implementations, the functions marked in the blocks may occur in a different order than those shown in the drawings. For example, two consecutive blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, may be implemented using a dedicated hardware-based system that performs the specified function or action, or using a combination of dedicated hardware and computer instructions.

[0360] Example embodiments have been disclosed herein, and while specific terminology has been used, it is for illustrative purposes only and should be construed as such, and is not intended to be limiting. In some instances, it will be apparent to those skilled in the art that features, characteristics, and / or elements described in conjunction with particular embodiments may be used alone, or in combination with features, characteristics, and / or elements described in conjunction with other embodiments, unless otherwise expressly indicated. Therefore, those skilled in the art will understand that various changes in form and detail may be made without departing from the scope of the invention as set forth in the appended claims.

Claims

1. An anomaly detection method applied to an engine system, characterized in that, include: The detection steps in the current driving cycle include: The steps for periodically checking the pressure signal are as follows: the pressure signal at the EGR valve inlet is first detected and processed to obtain the corresponding pressure maximum time interval array and pressure minimum time interval array, and based on the pressure maximum time interval array and pressure minimum time interval array, it is determined whether the periodicity of the pressure signal at the EGR valve inlet is abnormal. The pressure maximum time interval array contains multiple first elements, and the pressure minimum time interval array contains multiple second elements. The first element is the time interval between the maximum pressure detected at the EGR valve inlet in two adjacent sampling periods, and the second element is the time interval between the minimum pressure detected at the EGR valve inlet in two adjacent sampling periods. The steps for checking the pressure signal fluctuation are as follows: perform a second detection process on the pressure signal at the EGR valve inlet and perform at least two different filtering processes on the detection results. Obtain the corresponding pressure difference array based on the filtering results of each filtering process, and determine whether the pressure signal fluctuation at the EGR valve inlet is abnormal based on all the pressure difference arrays. The pressure difference array contains multiple third elements, which are the difference between the pressure output value of the later sampling period after corresponding filtering and the pressure output value of the previous sampling period after corresponding filtering.

2. The method according to claim 1, characterized in that, The steps of performing a second detection process on the pressure signal at the EGR valve inlet and applying at least two different filtering processes to the detection results, and obtaining the corresponding pressure difference array based on the filtering results of each filtering process, include: The pressure signal at the EGR valve inlet is subjected to a second detection process to obtain the pressure output values ​​of multiple sampling periods output by the pressure sensor at the EGR valve inlet. , n is the number of sampling cycles in the second detection process; Pressure output values ​​for multiple sampling periods The filtered pressure values ​​were obtained by applying three different filtering methods. , , , , , The pressure output values ​​for the i-th sampling period are respectively The pressure values ​​were obtained by three different filtering processes, all of which were first-order low-pass filters but with different filter coefficients. Based on the filtering results of the three filtering processes, three corresponding pressure difference arrays P1[n], P2[n], and P3[n] are obtained: in, ; in, ; in, .

3. The method according to claim 2, characterized in that, The filter coefficients for the first-order low-pass filter processing corresponding to the pressure difference array P1[n] are: The filter coefficients for the first-order low-pass filter processing corresponding to the pressure difference array P2[n] are: The filter coefficients for the first-order low-pass filter processing corresponding to the pressure difference array P3[n] are: ; When the engine speed change rate is not in a stable state during the second detection process, the filter coefficient... , and The values ​​are preset constants C1, C2, and C3, respectively, where C1, C2, and C3 are all greater than 0 and less than 0.

5. At this point, the step of determining whether the pressure signal fluctuation at the EGR valve inlet is abnormal based on the entire pressure difference array includes: From the three pressure difference arrays P1[n], P2[n], and P3[n], count the total number of values ​​of i that satisfy any of the following conditions, Q3; Condition 1a. >0、 <0、 <0, and Greater than or equal to the preset threshold ; Condition 2a <0、 >0、 >0, and Greater than or equal to the preset threshold ; Condition 3a >0、 >0、 <0, and Greater than or equal to the preset threshold ; Condition 4a <0、 <0、 >0, and Greater than or equal to the preset threshold ; The total number Q3 is compared with the third preset threshold CNT3; when Q3 > CNT3, abnormal pressure signal fluctuation at the EGR valve inlet is detected; when Q3 ≤ CNT3, normal pressure signal fluctuation at the EGR valve inlet is detected. When the engine speed change rate is stable during the second detection process, the filter coefficient... , and The values ​​are respectively , , C4, C5, and C6 are all greater than 0 and less than 0.5; at this time, the step of determining whether the pressure signal fluctuation at the EGR valve inlet is abnormal based on the entire pressure difference array includes: Count the total number of values ​​of i that satisfy any of the following conditions from the three pressure difference arrays P1[n], P2[n] and P3[n]; Condition 1b >0、 <0、 <0, and Greater than or equal to the preset threshold ; Condition 2b <0、 >0、 >0, and Greater than or equal to the preset threshold ; Condition 3b >0、 >0、 <0, and Greater than or equal to the preset threshold ; Condition 4b <0、 <0、 >0, and Greater than or equal to the preset threshold ; The total number Q4 is compared with the fourth preset threshold CNT4; when Q4 > CNT4, the pressure signal fluctuation at the EGR valve inlet is detected to be abnormal; when Q4 ≤ CNT4, the pressure signal fluctuation at the EGR valve inlet is detected to be normal. in, This represents the average value of the target EGR rate of the engine system during the second detection process. This represents the average engine speed during the second detection process. The default speed is pre-calibrated. , , , These are the pre-defined basic calibration threshold values. and All are not greater than and Any one of them.

4. The method according to claim 1, characterized in that, The pressure signal fluctuation verification step, and prior to the second detection processing of the pressure signal at the EGR valve inlet, also includes: a pre-fluctuation verification monitoring step, specifically including: The opening of the mixing valve in the engine control system is maintained at its maximum value; Monitor the overall engine system to ensure it is operating normally, and monitor the EGR subsystem within the engine system to ensure it is operating stably. When the engine system as a whole is in normal operation and the EGR subsystem is in stable operation for a continuous period of time t2 within the current monitoring cycle, the second detection and processing step of the pressure signal at the EGR valve inlet is executed. If the engine system as a whole is in normal operation and the EGR subsystem is in stable operation for a continuous period of less than the preset time t2, and the opening of the EGR valve remains stable throughout the current monitoring cycle, then the preset time t2 is initialized to the preset initial value, and the detection steps in the current driving cycle end. If the engine system as a whole is in normal operation and the EGR subsystem is in stable operation for a continuous period of less than the preset time t2, and the opening of the EGR valve has been unstable during the current monitoring cycle, then the preset time t2 is updated by adding the preset step time to the preset time t2, and the detection step in the current driving cycle ends.

5. The method according to claim 1, characterized in that, The steps for determining whether the pressure signal periodicity at the EGR valve inlet is abnormal based on the array of maximum pressure time intervals and the array of minimum pressure time intervals include: When the engine speed change rate is not stable during the first detection process, the total number of elements Q1_MAX in the maximum pressure time interval array whose values ​​are less than the first reference time interval value T1 is counted, and the total number of elements Q1_MIN in the minimum pressure time interval array whose values ​​are less than the first reference time interval value T1 is counted. The first reference time interval value T1 is: The total number of elements Q1_MAX and Q1_MIN are compared with a first preset threshold CNT1. If at least one of Q1_MAX and Q1_MIN is greater than CNT1, a periodic abnormality in the pressure signal at the EGR valve inlet is detected. If both Q1_MAX and Q1_MIN are less than or equal to CNT1, a periodic normality in the pressure signal at the EGR valve inlet is detected. When the engine speed change rate is stable during the first detection process, the total number of elements Q2_MAX in the maximum pressure time interval array whose values ​​are less than the second reference time interval value T2 is counted, and the total number of elements Q2_MIN in the minimum pressure time interval array whose values ​​are less than the second reference time interval value T2 is counted. The second reference time interval value T2 is: The total number of elements Q2_MAX and Q2_MIN are compared with a second preset threshold CNT2. If at least one of Q2_MAX and Q2_MIN is greater than CNT2, a periodic abnormality in the pressure signal at the EGR valve inlet is detected. If both Q2_MAX and Q2_MIN are less than or equal to CNT2, a periodic normality in the pressure signal at the EGR valve inlet is detected. in, This represents the average value of the target EGR rate of the engine system during the first detection and processing step. This represents the average engine speed during the first detection process. This represents the average temperature at the EGR valve inlet during the first detection process. The default speed is pre-calibrated. The default temperature at the EGR valve inlet is pre-calibrated. This is the first preset adjustment coefficient. The second preset adjustment coefficient is d0~d2 and d3~d5 are the preset calibration durations, and d2≥d5, d1≥d4, and d0≥d3.

6. The method according to claim 5, characterized in that, Before the steps of comparing the total number of elements Q1_MAX and the total number of elements Q1_MIN with the first preset threshold CNT1, the method further includes: The steps for determining the first preset threshold number CNT1 include: When the EGR valve is closed during the first detection process, the absolute value of the average fresh air intake flow rate into the cylinder during the first detection process is used as the basis. Compared to the pre-defined default traffic ratio The ratio is determined using the first mapping process. The corresponding first preset number threshold CNT1; When the EGR valve is not closed during the first detection process, the absolute value of the average fresh air intake flow rate into the cylinder during the first detection process is used as the basis. Compared to the pre-defined default traffic ratio The ratio was determined using the second mapping process. The corresponding first preset number threshold CNT1; Among them, the first preset number threshold CNT1 determined based on the first mapping process or the second mapping process and the ratio They are positively correlated, and for the same ratio The first preset number threshold determined by the first mapping process is less than or equal to the first preset number threshold determined by the second mapping process; And / or, before the step of comparing the total number of elements Q2_MAX and the total number of elements Q2_MIN with the second preset threshold CNT2, the method further includes: The steps for determining the second preset threshold number CNT2 include: When the EGR valve is closed during the first detection process, the absolute value of the average fresh air intake flow rate into the cylinder during the first detection process is used as the basis. Compared to the pre-defined default traffic ratio The ratio was determined using a third mapping process. The corresponding second preset threshold number of times, CNT2; When the EGR valve is not closed during the first detection process, the absolute value of the average fresh air intake flow rate into the cylinder during the first detection process is used as the basis. Compared to the pre-defined default traffic ratio The ratio was determined using the fourth mapping process. The corresponding second preset threshold number of times, CNT2; Among them, the second preset number threshold CNT2 determined based on the third or fourth mapping process and the ratio They are positively correlated, and for the same ratio The second preset number threshold determined by the third mapping process is less than or equal to the second preset number threshold determined by the fourth mapping process.

7. The method according to claim 5, characterized in that, Following the step of periodically checking pressure signals, the following is also included: When the periodic pressure signal at the EGR valve inlet is determined to be periodically abnormal during the periodic pressure signal verification step, the first preset counting parameter is adjusted. Second preset counting parameters All values ​​are initialized to 0; When the pressure signal at the EGR valve inlet is determined to be periodically normal during the periodic pressure signal verification step, the first preset counting parameter is adjusted based on the performance of the engine speed change rate during the periodic pressure signal verification process. Second preset counting parameters At least one of them shall be updated; wherein, if at least once during the step of periodically checking the pressure signal, the engine speed change rate is not in a stable state, then the first preset counting parameter shall be updated. Increment by 1; if the engine speed change rate is found to be stable at least once during the periodic check of the pressure signal, then increment the second preset count parameter. Add 1; Determine the first preset counting parameter Second preset counting parameters Does it meet one of the following conditions: Condition 1c Equal to the first preset counting threshold G1 and If G is equal to 0, then G1 ≥ 3; Condition 2c Equal to the second preset counting threshold G2 and If G equals 0, then G2 ≥ 2; Condition 3c and Both are not 0 and their sum equals the third preset counting threshold G3, where G3 ≥ 3; If satisfied, proceed with the step of checking the fluctuation of the pressure signal, and set the first preset counting parameter. Second preset counting parameters All values ​​are initialized to 0; if this condition is not met, the system proceeds normally to the next detection step in the driving cycle.

8. The method according to claim 5, characterized in that, Following the step of checking for fluctuations in pressure signals, the following steps are also included: Detect whether the step of periodically checking pressure signals has been performed during the current driving cycle; When it is detected that a step of periodically checking the pressure signal has been performed during the current driving cycle, and the step of checking the pressure signal fluctuation during the current driving cycle determines that the pressure signal fluctuation is abnormal, wait for the abnormal fault to be restored, and then proceed to the detection step in the next driving cycle normally after the abnormal fault is restored. If it is detected that the step of periodically checking the pressure signal has been performed in the current driving cycle, and the step of checking the pressure signal fluctuation in the current driving cycle has determined that the pressure signal fluctuation is normal, then the step of periodically checking the pressure signal in the next driving cycle is skipped, and the step of checking the pressure signal fluctuation in the next driving cycle is executed directly. If it is detected that the step of periodically checking the pressure signal has not been performed during the current driving cycle, and the step of checking the pressure signal fluctuation during the current driving cycle determines that the pressure signal fluctuation is abnormal, then the first update processing rule is used to adjust the first preset adjustment coefficient. Or the second preset adjustment coefficient Perform an update and wait for the abnormal fault to be resolved, and then proceed to the detection steps in the next driving cycle normally after the abnormal fault is resolved; If it is detected that the step of periodically checking the pressure signal has not been performed during the current driving cycle, and the step of checking the pressure signal fluctuation during the current driving cycle determines that the pressure signal fluctuation is normal, then the second update processing rule is used to adjust the first preset adjustment coefficient. Or the second preset adjustment coefficient Perform the update and proceed normally to the next driving cycle's detection steps; The first update processing rules include the following: If, during the periodic pressure signal verification process, the engine system's operating status is last detected to include: the engine speed change rate being unstable and the EGR valve being open, then the first preset adjustment coefficient will be adjusted. Decrease the first preset step value z1 to perform the update; If, during the periodic pressure signal verification process, the last monitored engine system operating status includes: engine speed change rate not being stable and EGR valve being closed, then the first preset adjustment coefficient will be adjusted. Decrease the second preset step value z2 to perform the update; If, during the periodic pressure signal verification process, the last monitored state of the engine system includes: the engine speed change rate is stable and the EGR valve is not closed, then the second preset adjustment coefficient will be adjusted. Decrease the third preset step value z3 to perform the update; If, during the periodic pressure signal verification process, the engine system's operating status is last detected to include: the engine speed change rate being unstable and the EGR valve being closed, then the second preset adjustment coefficient will be adjusted. Decrease the fourth preset step value z4 to perform the update; The second update processing rules include the following: If, during the periodic pressure signal verification process, the engine system's operating status is last detected to include: the engine speed change rate being unstable and the EGR valve being open, then the first preset adjustment coefficient will be adjusted. Add the first preset step value z1 to perform the update; If, during the periodic pressure signal verification process, the last monitored engine system operating status includes: engine speed change rate not being stable and EGR valve being closed, then the first preset adjustment coefficient will be adjusted. Add a second preset step value z2 to perform the update; If, during the periodic pressure signal verification process, the last monitored state of the engine system includes: the engine speed change rate is stable and the EGR valve is not closed, then the second preset adjustment coefficient will be adjusted. Add a third preset step value z3 to perform the update; If, during the periodic pressure signal verification process, the engine system's operating status is last detected to include: the engine speed change rate being unstable and the EGR valve being closed, then the second preset adjustment coefficient will be adjusted. Add the fourth preset step value z4 to perform the update; Where z1 < z2, z3 < z4, z3 < z1, z4 < z2.

9. The method according to claim 8, characterized in that, The steps for performing the first detection and processing of the pressure signal at the EGR valve inlet and obtaining the corresponding pressure maximum value time interval array and pressure minimum value time interval array include: The pressure signal at the EGR valve inlet is first detected and processed to obtain the maximum and minimum pressure values ​​and the corresponding time points collected by the pressure sensor at the EGR valve inlet in m sampling periods. Based on the average engine speed in the first detection process Determine the number M of sampling periods to be excluded, where M is related to... Positively correlated; Remove the maximum and minimum pressure values ​​and their corresponding time points from the first M sampling cycles in the first detection process; An array of time intervals for maximum pressure is generated based on the time points of the maximum pressure collected in the last mM sampling cycles of the first detection process, and an array of time intervals for minimum pressure is generated based on the time points of the minimum pressure collected in the last mM sampling cycles of the first detection process.

10. The method according to claim 9, characterized in that, The steps for performing the first detection and processing on the pressure signal at the EGR valve inlet to obtain the maximum and minimum pressure values ​​and corresponding time points collected by the pressure sensor at the EGR valve inlet during m sampling periods include: Acquire all raw pressure values ​​obtained by the pressure sensor over m sampling periods; All raw pressure data are subjected to a preset first-order low-pass filter to obtain filtered pressure data for m sampling periods. The filter coefficients in the preset first-order low-pass filter process are: : Wherein, when the particulate matter trap in the engine system is in active regeneration state during the first detection and processing, the filter coefficient ; When the particulate matter filter in the engine system is in a non-active regeneration state during the first detection and processing, the filter coefficient... ; and These are two pre-calibrated reference filter coefficients, and , This is the third preset adjustment coefficient. This is the fourth preset adjustment coefficient; From the filtered pressure data of m sampling periods, determine the maximum and minimum pressure values ​​and the corresponding time points in each sampling period; The first update processing rule is used to adjust the first preset adjustment coefficient. Or the second preset adjustment coefficient The update process also includes: applying the first update processing rule to adjust the third preset adjustment coefficient. Or the fourth preset adjustment coefficient Update; The second update processing rule is used to adjust the first preset adjustment coefficient. Or the second preset adjustment coefficient The update process also includes: using a second update processing rule to adjust the third preset adjustment coefficient. Or the fourth preset adjustment coefficient Update; The first update processing rules also include the following: If, during the periodic pressure signal verification process, the last monitored state of the engine system includes: the engine speed change rate is not stable and the particulate filter is in active regeneration mode, then the third preset adjustment coefficient will be adjusted. Subtract the fifth preset step value z5; If, during the periodic pressure signal verification process, the engine system's operating status is last detected as follows: the engine speed change rate is not stable and the particulate filter is in a non-active regeneration state, then the third preset adjustment coefficient will be adjusted. Subtract the sixth preset step value z6, and adjust the fourth preset coefficient. Subtract the seventh preset step value z7; If, during the periodic pressure signal verification process, the last monitored state of the engine system includes: a stable engine speed change rate and the particulate filter in active regeneration mode, then the third preset adjustment coefficient will be adjusted. Subtract the eighth preset step value z8; If, during the periodic pressure signal verification process, the engine system's operating status is last detected as follows: the engine speed change rate is not stable and the particulate filter is in a non-active regeneration state, then the third preset adjustment coefficient will be adjusted. Subtract the ninth preset step value z9, and adjust the fourth preset adjustment coefficient. Subtract the tenth preset step value z10; The second update processing rules also include the following: If, during the periodic pressure signal verification process, the last monitored state of the engine system includes: the engine speed change rate is not stable and the particulate filter is in active regeneration mode, then the third preset adjustment coefficient will be adjusted. Add the fifth preset step value z5, and add the eleventh preset step value z11 to the fourth preset adjustment coefficient; If, during the periodic pressure signal verification process, the engine system's operating status is last detected as follows: the engine speed change rate is not stable and the particulate filter is in a non-active regeneration state, then the fourth preset adjustment coefficient will be adjusted. Add the seventh preset step value z7; If, during the periodic pressure signal verification process, the last monitored state of the engine system includes: a stable engine speed change rate and the particulate filter in active regeneration mode, then the third preset adjustment coefficient will be adjusted. Add the eighth preset step value z8; If, during the periodic pressure signal verification process, the engine system's operating status is last detected as follows: the engine speed change rate is not stable and the particulate filter is in a non-active regeneration state, the third preset adjustment coefficient will be adjusted. Add the ninth preset step value z9, and adjust the fourth preset coefficient. Add the tenth preset step value z10; Among them, z5 > z6, z5 > z7 > z11, z5 > z8 > z10 > z9.

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