A diagnostic method, electronic device, and storage medium for abnormal engine cylinder deactivation and torque reduction

Abstract

The present invention discloses a method for diagnosing abnormal engine cylinder deactivation and torque reduction, an electronic device, and a storage medium. The method comprises: performing abnormal engine cylinder deactivation and torque reduction diagnosis when enabling conditions for the diagnosis are met; detecting the cylinder number of the abnormally deactivated cylinder using the first method when activation conditions for a first method are met; detecting the cylinder number of the abnormally deactivated cylinder using the second method when activation conditions for a second method are met; and jointly determining the cylinder number of the abnormally deactivated cylinder using the cylinder numbers detected by the first and second methods. The present invention improves the accuracy of abnormal engine cylinder deactivation and torque reduction judgment by selecting different methods for abnormal cylinder deactivation and torque reduction judgment under different operating conditions and combining the results of the two methods, thereby reminding the driver to perform timely maintenance and inspection to protect the engine.

Description

Technical Field

[0001] The present invention relates to the technical field of engine control, and in particular to a method for diagnosing abnormal engine cylinder deactivation and torque reduction, an electronic device, and a storage medium. Background Art

[0002] Failure to promptly identify abnormal engine deactivation and torque reduction can negatively impact engine performance, emissions, and economy. Therefore, it's crucial to diagnose and identify abnormal engine deactivation and torque reduction, alerting the driver to prompt repairs and inspections to protect the engine. Summary of the Invention

[0003] The purpose of the present invention is to provide a method, electronic equipment and storage medium for diagnosing abnormal engine cylinder deactivation and torque reduction, which are used to diagnose and identify whether the engine has abnormal cylinder deactivation and torque reduction, thereby reminding the driver to carry out timely maintenance and inspection to protect the engine.

[0004] To achieve the above objectives, according to a first aspect of the present invention, a method for diagnosing abnormal engine cylinder deactivation and torque reduction is provided, the method comprising:

[0005] When the engine abnormal cylinder deactivation and torque reduction diagnosis enabling conditions are met, the engine abnormal cylinder deactivation and torque reduction diagnosis is performed:

[0006] When the activation conditions of the first method for diagnosing abnormal engine cylinder deactivation and torque reduction are met, the cylinder number of the abnormally deactivated cylinder is detected by the first method for diagnosing abnormal engine cylinder deactivation and torque reduction. The first method for diagnosing abnormal engine cylinder deactivation and torque reduction includes:

[0007] Obtaining the operating time of each cylinder of the engine within a specific crankshaft operating angle range, and calculating the average operating time of each cylinder of the engine within a plurality of consecutive sampling periods; wherein the specific crankshaft operating angle range is the crankshaft angle from 80° after compression top dead center of each cylinder of the engine to 260° after compression top dead center of its corresponding cylinder;

[0008] Divide the evaluation area according to the engine speed and determine the evaluation time update coefficient of each cylinder of the engine in each evaluation area;

[0009] determining whether activation conditions for an engine abnormal cylinder deactivation diagnosis evaluation time update optimization process are met; if not, maintaining the evaluation time update coefficients of each cylinder of the engine in each evaluation area unchanged; and if so, determining a value of an evaluation time update optimization counter, and determining an initial value of the evaluation time update coefficient based on the evaluation time update coefficient and the average operating time value;

[0010] Determine the value of the flag bit according to the value of the evaluation time update optimization counter, and determine the updated evaluation time update coefficient according to the value of the flag bit, the initial value of the evaluation time update coefficient and the evaluation time update coefficient;

[0011] Determine a final running time according to the value of the flag bit, the updated evaluation time update coefficient, and the running time;

[0012] Calculating an average value of the final operating time of each cylinder of the engine within a plurality of consecutive sampling periods according to the final operating time, and determining a maximum value and a minimum value of the average value of the final operating time;

[0013] determining a value of an initial flag indicating whether a fixed cylinder is abnormally deactivated according to a maximum value and a minimum value of the final average value of the operating time;

[0014] determining the cylinder number of the abnormally deactivated cylinder according to the value of the initial flag indicating whether the fixed cylinder is abnormally deactivated;

[0015] When the activation condition of the second engine abnormal cylinder deactivation and torque reduction diagnostic method is met, the cylinder number of the abnormally deactivated cylinder is detected by the second engine abnormal cylinder deactivation and torque reduction diagnostic method;

[0016] The cylinder number of the abnormal engine deactivation is determined by jointly determining the cylinder number of the abnormal engine deactivation using the first method for diagnosing abnormal engine deactivation and torque reduction and the cylinder number detected using the second method for diagnosing abnormal engine deactivation and torque reduction.

[0017] In the above solution, the conditions for enabling the diagnosis of abnormal engine cylinder deactivation and torque reduction include:

[0018] (1) Enter the fire diagnosis area specified in the regulations;

[0019] (2) No fuel cut-off request;

[0020] (3) The gear position has not changed, and the first time after the gear position changes is delayed;

[0021] (4) The clutch is in a fully engaged state, and the clutch is delayed for a second time after being fully engaged;

[0022] (5) Non-uneven road surface;

[0023] (6) The water temperature is within the preset range;

[0024] (7) The throttle opening fluctuates within a certain range;

[0025] (8) The engine is in running state;

[0026] When all the above conditions are met, the engine abnormal cylinder deactivation and torque reduction diagnosis enabling conditions are met.

[0027] In the above scheme, the activation condition of the first abnormal engine cylinder deactivation and torque reduction diagnostic method is determined by the average engine speed and the average engine intake air density; wherein the average engine speed and the average engine intake air density are respectively the average of the engine speed and the engine intake air density of the current sampling period and the previous sampling periods;

[0028] If the activation condition of the first engine abnormal cylinder deactivation and torque reduction diagnostic method in the current sampling period is not met, the first engine abnormal cylinder deactivation and torque reduction diagnostic method is not activated;

[0029] If the activation conditions of the first engine abnormal cylinder deactivation and torque reduction diagnostic method are met in the current sampling period, and the activation conditions of the first engine abnormal cylinder deactivation and torque reduction diagnostic method in the previous sampling periods are met, then the first engine abnormal cylinder deactivation and torque reduction diagnostic method is activated;

[0030] In other cases, the first engine abnormal cylinder deactivation and torque reduction diagnostic method is not activated;

[0031] The activation conditions for the second engine abnormal cylinder deactivation and torque reduction diagnostic method are similar.

[0032] In the above solution, the activation conditions for the optimization process of updating the engine abnormal cylinder deactivation diagnosis evaluation time include:

[0033] (1) The engine is in running state;

[0034] (2) All cylinders of the engine are in the fuel cut-off state;

[0035] (3) The engine does not directly participate in driving the vehicle;

[0036] (4) The engine does not experience knock or pre-ignition;

[0037] (5) The running time of each cylinder of the engine is not zero in several consecutive sampling periods;

[0038] (6) The engine has no malfunction;

[0039] When all of the above conditions are met, the activation conditions for the engine abnormal cylinder deactivation diagnosis evaluation time update optimization process are met.

[0040] In the above solution, determining the value of the evaluation time update optimization counter and determining the initial value of the evaluation time update coefficient according to the evaluation time update coefficient and the average value of the running time include:

[0041] If any of the following conditions is met, the value of the evaluation time update optimization counter is reset to 1, and the initial value of the evaluation time update coefficient of each cylinder of the engine is reset to the evaluation time update coefficient within the current evaluation area:

[0042] (1) The activation conditions for the optimization process of updating the engine abnormal cylinder deactivation diagnosis evaluation time are not met;

[0043] (2) Changes in the current evaluation area;

[0044] If both of the above conditions are not met, the value of the evaluation time update optimization counter is increased by 1 after each sampling period, and the initial value of the evaluation time update coefficient is accumulated at the same time. The accumulation method is as follows:

[0045] For each cylinder of the engine, the quotient of its average operating time and the average operating time of all the cylinders of the engine is calculated in each sampling period, and the initial value of the evaluation time update coefficient accumulated in the previous sampling period is added to the inverse of the quotient to obtain the initial value of the evaluation time update coefficient accumulated in the current sampling period.

[0046] In the above solution, the value of the flag bit is determined according to the value of the evaluation time update optimization counter, and the updated evaluation time update coefficient is determined according to the value of the flag bit, the initial value of the evaluation time update coefficient, and the evaluation time update coefficient, including:

[0047] If the value of the evaluation time update optimization counter of the current evaluation area is not less than the preset value Cnt A1 The number of times Cnt AdaptWeightCounter Greater than the preset number Cnt B1 , then the flag value is 1; otherwise the flag value is 0; where, the number of times Cnt AdaptWeightCounter The accumulation method is: after the value of the optimization counter of the evaluation time of the current evaluation area is reset, it is accumulated again. If the value of the optimization counter of the evaluation time of the current evaluation area is not less than the preset value Cnt A1 , then the number Cnt AdaptWeightCounter Add 1; every time the evaluation time of the current evaluation area is updated and the optimization counter value is reset, the number of times Cnt AdaptWeightCounter Accumulate at most once;

[0048] When the flag value is 0 and the value of the evaluation time update optimization counter of the current evaluation area is not less than the preset value Cnt A1 , updating the evaluation time update coefficient by calculating, for a cylinder in the current evaluation area, the product of the initial value of the evaluation time update coefficient and the first weighting coefficient, and simultaneously calculating the difference between 1 and the first weighting coefficient and the product of the difference and the evaluation time update coefficient corresponding to the cylinder in the current evaluation area; the sum of the two products is the updated evaluation time update coefficient;

[0049] When the flag value is 1 and the value of the evaluation time update optimization counter of the current evaluation area is not less than the preset value Cnt A2, updating the evaluation time update coefficient by calculating, for a cylinder in the current evaluation area, the product of the initial value of the evaluation time update coefficient and the second weighting coefficient, and simultaneously calculating the difference between 1 and the second weighting coefficient and the product of the difference and the evaluation time update coefficient corresponding to the cylinder in the current evaluation area, the sum of the two products being the updated evaluation time update coefficient; wherein both the first weighting coefficient and the second weighting coefficient are less than 1, and the second weighting coefficient is not greater than the first weighting coefficient;

[0050] Determining a final running time according to the value of the flag bit, the updated evaluation time update coefficient, and the running time includes:

[0051] When the flag value is 0, the running time of each cylinder of the engine is the final running time;

[0052] When the value of the flag bit is 1, the product of the running time of each cylinder of the engine and the corresponding updated evaluation time update coefficient is the final running time.

[0053] In the above solution, determining the value of the initial flag indicating whether the fixed cylinder is abnormally deactivated based on the maximum and minimum values ​​of the final average value of the operating time includes:

[0054] Determining a characteristic coefficient according to the maximum and minimum values ​​of the final running time average values ​​includes:

[0055] Get the maximum value T among the final running time averages in the current sampling period Max With the minimum value T Min , and calculate the corresponding intermediate value

[0056] Similarly, calculate the intermediate values ​​corresponding to several sampling periods before the current sampling period, and finally calculate the average value of all intermediate values, which is the characteristic coefficient;

[0057] Determining the value of an initial flag indicating whether a fixed cylinder is abnormally deactivated based on the characteristic coefficient and a preset threshold coefficient for determining whether the fixed cylinder is abnormally deactivated includes:

[0058] If the characteristic coefficient is greater than or equal to the preset threshold coefficient for determining whether the fixed cylinder is abnormally deactivated, the value of the initial flag bit for determining whether the fixed cylinder is abnormally deactivated is 1, otherwise it is 0;

[0059] The threshold coefficient for determining abnormal cylinder deactivation of a fixed cylinder is determined by the average engine speed and the average engine intake air density; the average engine speed and the average engine intake air density are the average values ​​of the engine speed and the engine intake air density during the current sampling period and several previous sampling periods, respectively.

[0060] Determining the cylinder number of the abnormally deactivated cylinder according to the value of the initial flag indicating whether the fixed cylinder is abnormally deactivated includes:

[0061] On the premise that the initial flag value of whether the fixed cylinder is continuously disconnected is 1, if:

[0062] Case 1: Determine the cylinder number whose average running time is equal to the maximum value;

[0063] Case 2: If a cylinder satisfies the following conditions, its cylinder number is determined: first, the difference between the maximum value and the average value of the cylinder's operating time is calculated, and then the quotient of the difference and the maximum value is calculated, and the quotient is greater than zero and less than a first preset value;

[0064] Case 3: The cylinder meeting the first case or the second case meets the following conditions: first, the difference between all the running time of the cylinder meeting the first case or the second case and the maximum value in a number of consecutive sampling periods is calculated, and then the quotient of these differences and the maximum value is calculated, and the quotient is less than zero and greater than a second preset value;

[0065] The fourth case: at least one cylinder does not meet the first or the second case;

[0066] Case 5: The following situation exists: When the cylinder numbers that meet the first or second conditions are recorded according to the cylinder working order, the number of cylinders that do not meet the first or second conditions between two consecutive cylinder numbers that meet the first or second conditions is not less than 2, and the cylinder number equal to the minimum value is not the next working cylinder number after the cylinder number that meets the first or second conditions;

[0067] If the first condition, the second condition, the third condition, the fourth condition, and the fifth condition are all satisfied, it indicates that the cylinder satisfying the first condition or the second condition has abnormal cylinder deactivation.

[0068] In the above solution, the second method for diagnosing abnormal engine cylinder deactivation and torque reduction includes:

[0069] Get the running time of each tooth of the engine crankshaft flywheel;

[0070] determining a starting crankshaft angle and tooth length for estimating engine combustion torque, determining an evaluation window for estimating engine combustion torque based on the starting crankshaft angle and tooth length, and obtaining an array of operating times of each tooth within the evaluation window in combination with the operating times of each tooth;

[0071] Filter the running time array of each tooth and output the filtered running time array of each tooth;

[0072] Estimating the engine speed based on the filter running time array of each tooth to obtain an engine speed array;

[0073] estimating the initial torque difference value of each tooth based on the engine speed during the operation of each tooth, and obtaining an array of initial torque difference values;

[0074] Filtering the initial value array of the torque difference of each tooth and outputting the filtered torque difference array of each tooth;

[0075] Calculating a total torque variation within the evaluation window based on the filtered torque difference array of each tooth;

[0076] The cylinder number of the abnormally deactivated cylinder is determined according to the total torque variation.

[0077] In the above solution, obtaining the running time of each tooth of the engine crankshaft flywheel includes:

[0078] The running time of each tooth refers to the time required for the engine flywheel to go from the current tooth to the next tooth when running; for a missing tooth, the average of the running times of the teeth before and after the missing tooth is taken as the running time of the missing tooth.

[0079] In the above scheme, determining a starting crankshaft angle and tooth length for estimating the engine combustion torque, determining an evaluation window for estimating the engine combustion torque based on the starting crankshaft angle and tooth length, and obtaining an array of the running times of each tooth within the evaluation window in combination with the running times of each tooth include:

[0080] Starting crankshaft angle phi S The method for determining tart is: phi Start =f1(n,rho)+b CatHeat ×f2(n,rho); where b C at H eat is the activation state of the catalyst light-off control. When the catalyst light-off control is activated, b C at H eat is 1, otherwise it is 0; f1(n,rho) and f2(n,rho) are calibration values, which are determined by the engine speed n and the density of fresh air entering the cylinder rho: After the catalyst is ignited, the calibration value f1(n,rho) and the first tooth length Cnt are calibrated T ooth A rray L en1, calibrate the calibration value f2(n,rho) and the second tooth length Cnt during the catalyst ignition process ToothArrayLen2 The calibration is determined based on the following: the difference between the combustion torque during abnormal cylinder deactivation and the combustion torque during normal cylinder deactivation within the evaluation window meets the preset requirements;

[0081] An evaluation window for estimating the engine combustion torque is determined based on the starting crankshaft angle and the tooth length, and the evaluation window and the running time array t of the four consecutive teeth after the evaluation window are obtained by combining the running time of each tooth. ToothTimes [0,1,2,...,Cnt ToothArrayLen +3]; in which, when the catalyst is not in the ignition state or the ignition state is completed, the tooth length Cnt ToothArrayLen =Cnt ToothArrayLen1 ; When the catalyst is ignited, the tooth length Cnt ToothArrayLen =Cnt ToothArrayLen2 ;

[0082] Filter the running time array of each tooth and output the filtered running time array of each tooth, including:

[0083] Calculate the initial value of the filter time t for the running time of each tooth ToothTimesFilterRaw [N]:

[0084] t ToothTimesFilterRaw [N] = r1 × t ToothTimes [N]+r2×t ToothTimes [N-1]+r3×t ToothTimes [N-2]

[0085] Where N is the running time array t ToothTimes [0,1,2,...,Cnt ToothArrayLen +3]; when N=0 or 1, t ToothTimesFilterRaw [0] = t ToothTimes [0], t ToothTimesFilterRaw [1] = t ToothTimes [0]; r1, r2, and r3 are weighting coefficients, the sum of which is 1. They are determined by the following method: the difference between the combustion torque during abnormal cylinder deactivation and the combustion torque during normal cylinder deactivation within the evaluation window meets the preset requirements;

[0086] Determine the filter run time t for each tooth ToothTimesFilter [N] = t ToothTimesFilterRaw [N+2], get the filter running time array t for each tooth ToothTimesFilter [0,1,2,...,Cnt ToothArrayLen +1];

[0087] The engine speed is estimated based on the filter running time array of each tooth to obtain the engine speed array, including:

[0088] Calculating engine speed Where C1 is the coefficient;

[0089] Get the engine speed array n EstRpm [0,1,2,...,CntToothArrayLen +1];

[0090] The initial torque difference value of each tooth is estimated based on the engine speed during the operation of each tooth, and an array of initial torque difference values ​​is obtained, including:

[0091] Calculate the initial value M of the torque difference of each tooth EstTrqErrRaw [N]=C2×[(n EstRpm [N]) 2 -(n EstRpm [N-1]) 2 ]; where C2 is the coefficient;

[0092] Get the torque difference initial value array M EstTrqErrRaw [0,1,2,...,Cnt ToothArrayLen +1];

[0093] Filter the initial value array of the torque difference of each tooth and output the filtered torque difference array of each tooth, including:

[0094] Similar to the running time array filtering, the filtered torque difference array M is obtained EstTrqErr [0,1,2,...,Cnt ToothArrayLen -1].

[0095] In the above solution, the total torque variation within the evaluation window is calculated based on the filtered torque difference array of each tooth, including:

[0096] The filtered torque difference array M EstTrqErr [0,1,2,...,Cnt ToothArrayLen -1] are added together to get the total torque change M TrqDetectDelta ;

[0097] Determining the cylinder number of the abnormally deactivated cylinder according to the total torque change includes:

[0098] The total torque change M TrqDetectDelta Filter to obtain the total torque change M after filtering TrqSumMeanNew :

[0099] M TrqSumMeanNew =(1-r TrqWeightMean )×M TrqSumMean (z)+r TrqWeightMean ×M TrqDetectDelta

[0100] Where M TrqSumMean (z) is the total torque change after filtering in the previous sampling period; r T rq W eight M ean is the total torque change filter coefficient;

[0101] Calculate the initial value S of the torque characteristic value used to evaluate whether the combustion torque is abnormal TrqDetectRaw :

[0102] S TrqDetectRaw =(1-r TrqWeightVar )×S TrqDetectRaw (z)+r TrqWeightVar ×(M TrqDetectDelta -M TrqSumMeanNew ) 2

[0103] Among them, S TrqDetectRaw (z) is the initial value of the torque characteristic value in the previous sampling period; r T rq W eight V ar is the initial value filter coefficient of the torque characteristic value, and the calculation method is:

[0104] r TrqWeightVar =(1-k TrqWeightVar )×r TrqWeightVar (z)+k TrqWeightVar ×(r TrqWeightGain ×b TrqDetectErr (z)+r TrqWeightInc )

[0105] Among them, r TrqWeightVar (z) is the initial value filter coefficient of the torque characteristic value of the previous sampling period; k T rq W eight V ar is the update coefficient; r TrqWeightGain is the gain coefficient; r TrqWeightInc is the cumulative coefficient; b TrqDetectErr (z) is the flag indicating whether the engine combustion torque is abnormal in the previous sampling period. If it is abnormal, it is set to 1; if it is not abnormal, it is set to 0;

[0106] The initial value of the torque characteristic value S TrqDetectRaw Filter and obtain the filtered torque characteristic value S TrqDetect :

[0107] S TrqDetect =(1-r TrqWeightVarFilt )×S TrqDetect (z)+r TrqWeightVar ×S TrqDetectRaw

[0108] Among them, S TrqDetect (z) is the total torque change after filtering in the previous sampling period; r TrqWeightVarFilt is the filtering coefficient of the torque characteristic value after filtering;

[0109] Determine the combustion torque abnormality judgment lower limit value M TrqBoundLower :

[0110]

[0111] Among them, k BunndLower is the coefficient of deviation of the lower limit;

[0112] Calculate the torque deviation M used to determine whether the engine combustion torque is abnormal ErrEst :

[0113] M ErrEst =M TrqDetectDelta -M TrqBoundLower

[0114] Determine whether the engine combustion torque is normal:

[0115] If M appears ErrEst <M ErrThresh , then b TrqDetectErr Set to 1, the engine combustion torque is abnormal; otherwise b TrqDetectErr is 0, and the engine combustion torque is normal; ErrThresh is the combustion torque deviation limit;

[0116] Determine the cylinder number of the abnormally shut down cylinder:

[0117] If b TrqDetectErr If set to 1, the cylinder number in the power stroke under the corresponding evaluation window is read, indicating that the corresponding cylinder has abnormally stopped.

[0118] In the above solution, the difference between the combustion torque during abnormal cylinder deactivation and the combustion torque during normal cylinder deactivation within the evaluation window meets the preset requirements, including:

[0119] The difference between the combustion torque during abnormal cylinder deactivation and the combustion torque during non-abnormal cylinder deactivation is divided by the combustion torque during non-abnormal cylinder deactivation to obtain a ratio.

[0120] If the absolute value of the average value of the ratio exceeds the preset ratio threshold, the preset requirement is met.

[0121] In the above scheme, the cylinder number detected by the first method for diagnosing abnormal engine cylinder deactivation and torque reduction and the cylinder number detected by the second method for diagnosing abnormal engine cylinder deactivation and torque reduction are used together to determine the cylinder number of the abnormal engine cylinder deactivation, including:

[0122] If the cylinder number detected by the first abnormal engine deactivation and torque reduction diagnostic method is the same as the cylinder number detected by the second abnormal engine deactivation and torque reduction diagnostic method, the corresponding cylinder has been abnormally deactivated; and the abnormal deactivation fault diagnosis for the corresponding cylinder will not be performed in subsequent vehicle driving cycles until the diagnostic instrument clears the fault.

[0123] If the first engine abnormal cylinder deactivation and torque reduction diagnostic method detects the cylinder number of the abnormal cylinder deactivation, but the second engine abnormal cylinder deactivation and torque reduction diagnostic method does not detect the same cylinder number as the abnormal cylinder deactivation, and the number of driving cycles that occur exceeds the preset number A, it is characterized as abnormal cylinder deactivation, and the combustion torque deviation limit M of the corresponding cylinder under the second engine abnormal cylinder deactivation and torque reduction diagnostic method is set to ErrThresh Updated to the first multiple; and in subsequent vehicle driving cycles, abnormal cylinder deactivation fault judgment of the corresponding cylinder will not be performed until the diagnostic instrument clears the fault;

[0124] If the first abnormal engine deactivation and torque reduction diagnostic method detects the cylinder number of an abnormally deactivated cylinder, but the second abnormal engine deactivation and torque reduction diagnostic method does not detect abnormal deactivation of the same cylinder number, and the number of driving cycles in which the abnormal deactivation occurs does not exceed the preset number A, then the combustion anomaly is indicated as being in a pending state, and the threshold coefficient for determining abnormal fixed cylinder deactivation for the corresponding cylinder under the first abnormal engine deactivation and torque reduction diagnostic method is updated to the second multiple, and is updated at most once per driving cycle, and abnormal cylinder deactivation fault determination for the corresponding cylinder is still performed in subsequent vehicle driving cycles;

[0125] If the second engine abnormal cylinder deactivation and torque reduction diagnostic method detects the cylinder number of the abnormally deactivated cylinder, but the first engine abnormal cylinder deactivation and torque reduction diagnostic method does not detect abnormal cylinder deactivation of the same cylinder number, and the number of driving cycles in which the abnormal cylinder deactivation occurs exceeds the preset number A, then abnormal cylinder deactivation is indicated, and the threshold coefficient for determining abnormal fixed cylinder deactivation of the corresponding cylinder under the first engine abnormal cylinder deactivation and torque reduction diagnostic method is updated to the first multiple, and abnormal cylinder deactivation fault determination for the corresponding cylinder is not performed in subsequent vehicle driving cycles until the diagnostic instrument clears the fault, at which time abnormal cylinder deactivation fault determination is performed again;

[0126] If the second engine abnormal cylinder deactivation and torque reduction diagnostic method detects the cylinder number of the abnormal cylinder deactivation, but the first engine abnormal cylinder deactivation and torque reduction diagnostic method does not detect the same cylinder number as the abnormal cylinder deactivation, and the number of driving cycles that occur does not exceed the preset number A, it indicates that the combustion abnormality is in an unresolved state, and the combustion torque deviation limit M of the corresponding cylinder under the second engine abnormal cylinder deactivation and torque reduction diagnostic method is set to ErrThresh The update is a multiple of the second and is updated at most once per driving cycle, and the corresponding cylinder abnormal deactivation fault judgment is still performed in subsequent vehicle driving cycles;

[0127] If the first engine abnormal cylinder deactivation and torque reduction diagnostic method and the second engine abnormal cylinder deactivation and torque reduction diagnostic method do not detect the same cylinder number, abnormal cylinder deactivation fault judgment is still performed in the subsequent vehicle driving cycle;

[0128] The first multiple is greater than 1, and the second multiple is less than 1.

[0129] According to a second aspect of the present invention, an electronic device is provided, which includes: a storage device for storing executable instructions; a processing device for executing the executable instructions stored in the storage device to implement the engine abnormal cylinder deactivation and torque reduction diagnosis method described in any of the above technical solutions.

[0130] According to a third aspect of the present invention, a storage medium is provided, in which a computer program is stored. When the computer program is executed, the method for diagnosing abnormal engine cylinder deactivation and torque reduction described in any of the above technical solutions is implemented.

[0131] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0132] The present invention selects different methods to judge abnormal engine cylinder deactivation and torque reduction under different working conditions, that is, the cylinder number of the abnormal engine cylinder deactivation and torque reduction is jointly determined by the cylinder number detected by the first abnormal engine cylinder deactivation and torque reduction diagnostic method and the cylinder number detected by the second abnormal engine cylinder deactivation and torque reduction diagnostic method, and if the judgment results are different, the judgment threshold is continuously updated, thereby improving the judgment accuracy of abnormal engine cylinder deactivation and torque reduction, thereby reminding the driver to carry out timely maintenance and inspection to protect the engine.

[0133] In addition, the first method for diagnosing abnormal engine deactivation and torque reduction obtains the operating time of each cylinder of the engine in a specific crankshaft operating angle range, and updates the operating time through the value of the flag, the updated evaluation time update coefficient and the operating time to obtain the final operating time; finally, the final operating time average value of each cylinder of the engine in several consecutive sampling cycles is calculated based on the final operating time, and the maximum and minimum values ​​in the final operating time average value are determined; and then, based on the maximum and minimum values ​​in the final operating time average value, the value of the initial flag bit indicating whether the fixed cylinder is abnormally deactivated is determined, thereby determining the cylinder number of the abnormally deactivated cylinder, thereby improving the accuracy of the abnormal cylinder deactivation and torque reduction diagnosis. BRIEF DESCRIPTION OF THE DRAWINGS

[0134] Figure 1 A flow chart of a method for diagnosing abnormal engine cylinder deactivation and torque reduction provided by an embodiment of the present invention;

[0135] Figure 2 A flow chart of a first method for diagnosing abnormal engine cylinder deactivation and torque reduction provided by an embodiment of the present invention;

[0136] Figure 3 A flow chart of a second method for diagnosing abnormal engine cylinder deactivation and torque reduction provided by an embodiment of the present invention;

[0137] Figure 4 A schematic structural diagram of an electronic device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0138] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only intended to illustrate the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

[0139] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like to indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0140] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "plurality" means at least two, such as two, three, etc., unless otherwise specifically defined.

[0141] In the present invention, unless otherwise specified or limited, the terms "installed," "connected," "connect," "fixed," etc. should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection; direct connection, or indirect connection through an intermediate medium; internal communication between two components, or interaction between two components, unless otherwise specified. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0142] In the present invention, unless otherwise expressly specified or limited, when a first feature is "above" or "below" a second feature, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediary. Furthermore, when a first feature is "above," "above," or "above" a second feature, it may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is "below," "below," or "below" a second feature, it may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0143] The embodiment of the present invention provides a method for diagnosing abnormal engine cylinder deactivation and torque reduction, such as Figure 1 shown.

[0144] To ensure the accuracy of the abnormal engine cylinder deactivation verification method, it needs to be performed under certain conditions. Determine the enabling conditions of the abnormal engine cylinder deactivation verification method (the enabling condition judgment sampling period in this example is 10ms):

[0145] (1) Enter the fire diagnosis area specified in the regulations;

[0146] (2) No fuel cut-off request;

[0147] (3) The gear position has not changed, and after the gear position has changed, a delay of 0.1s is required to activate the engine abnormal cylinder deactivation verification method;

[0148] (4) The clutch is in full engagement, and the engine abnormal cylinder deactivation verification method can only be activated after a delay of 1 second after the clutch is engaged;

[0149] (5) Non-uneven road surface;

[0150] (6) The water temperature is within the preset range and is higher than -6°C;

[0151] (7) The throttle opening fluctuation is small during the diagnosis process (the difference between the maximum and minimum throttle openings within 0.1s is less than 15%);

[0152] (8) The engine is in running state.

[0153] When all of the above conditions are met, the engine abnormal cylinder deactivation and torque reduction diagnosis enable conditions are met. After all of the above conditions have been met for a certain period of time, the engine abnormal cylinder deactivation verification can be performed. If the above conditions are not met, the vehicle's operating conditions may cause the engine abnormal cylinder deactivation verification to be misjudged.

[0154] Figure 2This is the first diagnostic method for determining abnormal engine cylinder deactivation and torque reduction. As shown in Table 1, it is primarily determined by the average engine speed and average engine intake density, primarily tested and verified on an engine test bench through active forced fuel cutoff. The average engine speed and average intake density are the averages of the current sampling cycle and the previous four, for a total of five sampling cycles, and are therefore updated in real time. The sampling cycle is 180° of crankshaft rotation, and for each cylinder, the crankshaft angle is from 80° after the compression top dead center of each cylinder to 260° after the compression top dead center of its corresponding cylinder. The test verification results of this example are shown in Table 1.

[0155] Table 1 Activation table of the first diagnostic method for judging abnormal engine cylinder deactivation and torque reduction

[0156]

[0157]

[0158] When the above is equal to 0, it means that the method is not activated; when it is equal to 1 and the first 8 sampling periods are not 0, it means that the method is activated; in other cases, it means that the method is not activated.

[0159] CN202010204064.9 "A gasoline engine misfire monitoring method" proposes to calculate the engine's running time within a certain crankshaft angle range near the compression top dead center of each cylinder and store it in an array. n [0,1,2,3…], where n is the cylinder number. However, as the life cycle of the engine combustion system progresses, the operating time may shift under different cylinders and different operating conditions, resulting in a decrease in the accuracy of abnormal cylinder deactivation diagnosis. The present invention uses the operating time (abnormal cylinder deactivation diagnosis evaluation time) T n Update processing optimization to improve the accuracy of abnormal cylinder deactivation diagnosis.

[0160] The first method of diagnosing abnormal engine cylinder deactivation and torque reduction is as follows: Figure 2 As shown, including:

[0161] The first step is to calculate the running time T of each cylinder n [0, 1, 2, 3…] and the corresponding cylinder's previous A times (A is 9 in this example), totaling A+1 times (10 times in this example). Since the engine in this example has 4 cylinders, for the sake of convenience, the following examples are all based on a 4-cylinder engine. The method for engines with other cylinder numbers is the same. Based on this, the average running time of each cylinder is formed. RawSegmentAvg [0,1,2,3], for example, t RawSegmentAvg[0] is the average time for the first cylinder, and so on. It is important to note that the default initial value for the first A run times is 0. The run time update cycle (sampling period) is 180° of crankshaft rotation, and each cylinder is from 80° of crankshaft angle after the compression top dead center of each cylinder to 260° after the compression top dead center of its corresponding cylinder.

[0162] The second step involves optimizing the abnormal cylinder deactivation diagnostic evaluation time and activating the conditional judgment method. In this example, the conditional judgment update check cycle is 10ms. This can only be performed when all of the following conditions are met. This occurs primarily when all cylinders of the engine request fuel cutoff. During this time, the evaluation time is learned and updated while the engine is running and the vehicle is coasting. The conditions are:

[0163] (1) The engine is in running state;

[0164] (2) All cylinders of the engine are in the fuel cut-off state;

[0165] (3) The engine is not directly involved in driving the vehicle, that is, the engine is not connected to the transmission system;

[0166] (4) The engine does not experience knock or pre-ignition;

[0167] (5) The running time of each cylinder of the engine in several consecutive sampling periods is not zero, that is, the A+1 running time of each cylinder calculated in the first step is not zero;

[0168] (6) The engine did not malfunction.

[0169] If all the above conditions are met, proceed to step 3. Otherwise, the update coefficient r of abnormal cylinder deactivation diagnosis evaluation time is n [0,1,2,...,9] remain unchanged. After entering the third step, the update period (sampling period) in all steps is 180° of crankshaft rotation. For each cylinder, the update period is from 80° after the compression top dead center of each cylinder to 260° after the compression top dead center of its corresponding cylinder.

[0170] The third step is to determine the update array for optimizing the abnormal cylinder deactivation diagnosis evaluation time. The evaluation time update coefficient is stored in different areas. The area division depends on the engine speed, that is, the storage address of the update coefficient is different at different engine speeds. n [0,1,2,...], which is saved after the vehicle is powered off, and its initial value is 1. Here, r1[0,1,2,...] is the evaluation time update coefficient for cylinder 1. In this example, 10 regions are divided according to engine speed. Therefore, the evaluation time update coefficient for cylinder 1 is r1[0,1,2,...,9], and the same applies to other cylinders. Specifically, in this example, 10 regions are divided according to engine speed, as shown in Table 2.

[0171] Table 2 Evaluation area division table

[0172]

[0173] If the engine speed is 750 rpm or less, the evaluation region is 0; if the engine speed is greater than 750 rpm and less than 1000 rpm, the evaluation region is 1, and so on. It should be noted that in this example, each speed range (i.e., evaluation region) of each cylinder stores an evaluation time update coefficient, and its initial value is 1.

[0174] Step 4: Determine the abnormal cylinder deactivation diagnosis evaluation time and update the optimized counter Cnt AdaptCounter and the final evaluation time update coefficient initial value r raw [0,1,2,3].

[0175] If any of the following conditions are met, Cnt AdaptCounter Reset to 1 and update the evaluation time coefficient to its initial value r raw [0,1,2,3](where r raw [0] is the initial value of the evaluation time update coefficient of the first cylinder, and so on) is reset to the update coefficient r1[0,1,2,...,9] stored at power-off, which is the same as the update coefficient of the current actual evaluation area:

[0176] (1) The activation conditions for the abnormal cylinder deactivation diagnosis evaluation time update optimization process are not met;

[0177] (2) The evaluation area changes.

[0178] If the above two conditions are not met, Cnt AdaptCounter Add 1 and accumulate the evaluation time to update the initial value r of the coefficient raw [0,1,2,3], the accumulation method is as follows, taking the first cylinder as an example, the other cylinders are the same:

[0179] where r raw [0](z) is the initial value of the cumulative evaluation time update coefficient obtained in the previous sampling period, That is the average running time of all cylinders.

[0180] Step 5: Determine the evaluation time update coefficient r for optimizing the abnormal cylinder deactivation diagnosis evaluation time update n [0,1,2,...,9]. The bit in the evaluation time update coefficient array is stored corresponding to the current evaluation area.

[0181] 1) Determine whether the evaluation time for the current evaluation area has completed its first update. If the first update has not yet been completed, the evaluation time is accumulated using a weighted approach. This design aims to prevent the learning parameters from being unstable when the first update is not completed, making the weighted approach more stable and accurate.

[0182] If the abnormal cylinder deactivation diagnosis evaluation time in the current evaluation area is updated, the optimized counter Cnt AdaptCounter Not less than the preset value Cnt A1 (This example takes 5) the number of times Cnt AdaptWeightCounter Greater than the preset number Cnt B1 (3 in this example), the evaluation time is updated for the first time, that is, the flag bit b FirstAdaptDone is 1; otherwise, flag bit b FirstAdaptDone is 0.

[0183] Among them, the number of times Cnt AdaptWeightCounter The update accumulation method is: its default value is 0, in the counter Cnt AdaptCounter After reset, re-accumulate and update the optimized counter Cnt AdaptCounter Not less than the preset value Cnt A1 After that, the counter Cnt AdaptWeightCounter Add 1. That is, each time the counter Cnt AdaptCounter After reset, Cnt AdaptCounter Update at most once.

[0184] It should be noted that the number Cnt AdaptWeightCounter and flag bit b FirstAdaptDone It will be saved after the vehicle is powered off, and its default value is 0.

[0185] 2) In flag bit b FirstAdaptDone When it is 0, the counter Cnt of abnormal cylinder deactivation diagnosis evaluation time is updated and optimized AdaptCounter Not less than the preset value Cnt A1 Only when the evaluation time update coefficient r is updated is it allowed to update n [0,1,2,...,9]. Otherwise, in the flag bit b FirstAdaptDone When it is 0, the evaluation time update coefficient r is not allowed to be updated n [0,1,2,...,9]. In the flag bit b FirstAdaptDone When it is 0, the counter Cnt of abnormal cylinder deactivation diagnosis evaluation time is updated and optimized AdaptCounter Not less than the preset value Cnt A1 When the evaluation time update coefficient r is updated n The update method for [0,1,2,...,9] is:

[0186] Assume that the current evaluation area is 0. If it is in other evaluation areas, the update method is similar. Update the update coefficient r under the current evaluation area n :

[0187] r n [0] = k AdaptWeight ×r raw [n]+(1-k AdaptWeight )×r n [0](z)

[0188] Among them, r raw [n] is the initial value of the evaluation time update coefficient r raw The value of the n+1th cylinder in [0,1,2,3], r n [0](z) is the update coefficient of the evaluation area 0 in the previous sampling period (i.e., the evaluation time update coefficient r n [0,1,2,...,9] when the evaluation area is 0 n [0], the default value for the first time is described above. )k AdaptWeight is the weighting coefficient, which is 0.15 in this example.

[0189] Based on the above rules, it can be determined that if the current evaluation area is in other areas, the update coefficient r n , which forms r n [0,1,2,...,9].

[0190] 3) In the flag bit b FirstAdaptDone When it is 1, the counter Cnt of abnormal cylinder deactivation diagnosis evaluation time is updated and optimized AdaptCounter Not less than the preset value Cnt A2 Time (where Cnt A2 Not less than Cnt A1 The main purpose is to make the evaluation time more stable and the update speed can be slower. In this example, 16) is used to allow the evaluation time update coefficient r to be updated. n [0,1,2,...,9]. Otherwise, in the flag bit b FirstAdaptDone When it is 1, the evaluation time update coefficient r is not allowed to be updated n [0,1,2,...,9]. In the flag bit b FirstAdaptDone When it is 1, the counter Cnt of abnormal cylinder deactivation diagnosis evaluation time is updated and optimized AdaptCounter Not less than the preset value Cnt A2 When the evaluation time update coefficient r is updated n The update method for [0,1,2,...,9] is:

[0191] Assume that the current evaluation area is 0. If it is in other evaluation areas, the update method is similar. Update the update coefficient r under the current evaluation arean :

[0192] r n [0] = k Adapt ×r raw [n]+(1-k Adapt )×r n [0](z)

[0193] Among them, r raw [n] is the initial value of the evaluation time update coefficient r raw The value of the n+1th cylinder in [0,1,2,3], r n [0](z) is the update coefficient of the evaluation area 0 in the previous sampling period (i.e., the evaluation time update coefficient r n [0,1,2,...,9] when the evaluation area is 0 n [0], the default value for the first time is described above)k Adapt is the weighting coefficient, k Adapt No more than k AdaptWeight , k Adapt In this example, 0.005 is used.

[0194] Based on the above rules, it can be determined that if the current evaluation area is in other areas, the update coefficient r n , which forms r n [0,1,2,...,9].

[0195] Step 6: Determine the final evaluation time for abnormal cylinder deactivation diagnosis.

[0196] 1) In the flag bit b FirstAdaptDone When it is 0, T n [0, 1, 2, 3…] is the final evaluation time T for abnormal cylinder deactivation diagnosis n-New [0,1,2,3…];

[0197] 2) In flag bit b FirstAdaptDone When T is 1, n [0,1,2,3…] multiplied by the update coefficient r n [0,1,2,...,9] The value in the current evaluation range is the final evaluation time T for abnormal cylinder deactivation diagnosis n-New [0,1,2,3…]. Assuming the evaluation area is 0, the final evaluation time T for abnormal cylinder deactivation diagnosis is n-New [0,1,2,3…]=T n [0,1,2,3…]*r n [0], used for abnormal cylinder deactivation evaluation of each cylinder.

[0198] The seventh step is to calculate the average operating time of each cylinder within N consecutive time periods (5 in this example), and calculate each cylinder separately to form the average operating time of each cylinder T n_Avg :

[0199]

[0200] Step 8: Find the maximum value of the average running time T Max and the minimum value T Min .

[0201] T Max =max(T 1_Avg , T 2_Avg , T 3_Avg , T 4_Avg )

[0202] T Min =min(T 1_Avg , T 2_Avg , T 3_Avg , T 4_Avg )

[0203] Step 9: Determine the initial flag position b of whether the fixed cylinder is abnormally shut down or not CynOffRaw .

[0204] 1) Determine the characteristic coefficient r used to judge abnormal deactivation of a fixed cylinder CynDetectRaw :Get the current sampling period The average value of the five sampling periods and the four sampling periods before it is the characteristic coefficient r CynDetectRaw .

[0205] 2) If r CynDetectRaw ≥r CynDetectOffLim , initial flag bit b CynOffRaw is 1; otherwise the initial flag bit b CynOffRaw is 0. CynDetectOffLim The threshold coefficient for determining abnormal cylinder deactivation of a fixed cylinder is determined by the average engine speed and the average engine intake air density, where the average engine speed and the average engine intake air density are respectively the average values ​​of the current sampling cycle and the previous four sampling cycles, a total of five sampling cycles. CynDetectOffLim The details can be obtained from the bench calibration.

[0206] Step 10: Determine the final flag position b of whether the fixed cylinder is abnormally shut down or not CynOff .

[0207] In the initial flag b CynOffRaw If the value is 1, then:

[0208] (1) Read T n_AvgWhich cylinder's average operating time is equal to T Max If they are equal, determine the cylinder number;

[0209] (2) If T Max With T n_Avg The difference between the average operating time of the cylinder and divided by T Max , the coefficient obtained is greater than 0, but less than the preset value, which is 0.05 in this example, to determine the cylinder number;

[0210] (3) T corresponding to the cylinder number that meets the first or second situation n_New [0], T n_New [1], T n_New [2], T n_New [3], T n_New Any value in [4] and T Max The difference, and divided by T Max , the coefficients obtained are all within the preset range, and in this example, 0.08 is taken;

[0211] 4) At least one cylinder does not meet the first or the second condition;

[0212] 5) The cylinder numbers that appear in the first or second case are recorded according to the cylinder working order. If there are two cylinder numbers that meet the first or second case consecutively, the number of cylinders that do not meet the first or second case is not less than 2, and the cylinder number T in this case is n_Avg With T Min The cylinder number that is equal is not the next working cylinder number of the cylinder number that appears in the first or second case. For example, suppose the engine is a 4-cylinder engine, and the cylinder working order is 1-3-4-2-1-3-4-2-..., the cylinder numbers that meet the first or second case are cylinder 1 and cylinder 2, and the middle working cylinders are cylinder 3 and cylinder 4, then the T corresponding to cylinder 4 is 4_Avg Not equal to T Min .

[0213] When the above five conditions are met at the same time (the first case must be met), it indicates that the cylinder in the first case or the second case has abnormal cylinder deactivation.

[0214] The above completes the entire description of the first abnormal cylinder deactivation and torque reduction diagnostic method.

[0215] Figure 3This is the second diagnostic method for determining abnormal engine cylinder deactivation and torque reduction. As shown in Table 3, this is also primarily determined by the average engine speed and average engine intake air density, primarily tested and verified on an engine test bench through active forced fuel cutoff. The average engine speed and average intake air density are the averages of the current sampling cycle and the previous four, for a total of five sampling cycles, and are therefore updated in real time. The sampling cycle is 180° of crankshaft rotation, and for each cylinder, the crankshaft angle is from 80° after the compression top dead center of each cylinder to 260° after the compression top dead center of its corresponding cylinder. The test verification results of this example are shown in Table 3.

[0216] Table 3 Activation table of the second diagnostic method for judging abnormal engine cylinder deactivation and torque reduction

[0217]

[0218] When the above is equal to 0, it means that the method is not activated; when it is equal to 1 and the first 8 sampling periods are not 0, it means that the method is activated; in other cases, it means that the method is not activated.

[0219] The second method of diagnosing abnormal engine cylinder deactivation and torque reduction is as follows: Figure 3 As shown, including:

[0220] The first step is to read the running time of each tooth of the engine crankshaft flywheel after the above conditions are met. There are 58 teeth plus 2 missing teeth on the flywheel. The running time of each tooth refers to the time it takes for the engine flywheel to go from the current tooth to the next tooth when it is running. The time between the rising edge of the current tooth and the rising edge of the next tooth can be calculated. Note that because there are two missing teeth, the default running time of each tooth is 0, which will cause the running time of a total of 3 teeth (the first tooth before the missing tooth and the second missing teeth) to be 0. However, the tooth running time is an important parameter and will cause misjudgment of the engine combustion torque estimation result. Therefore, it is necessary to optimize the running time of the three teeth and take the running time of the tooth before these three teeth (that is, the second tooth before the missing tooth) and the running time of the first tooth after the second missing tooth as the average value.

[0221] It should be noted that if the falling edge is used, the running time of a total of 3 teeth (the first tooth after the missing tooth, and 2 missing teeth) will be 0.

[0222] The third step is to determine the evaluation window for estimating the engine combustion torque, that is, to determine the starting crankshaft angle and the tooth length Cnt for the engine combustion torque estimation. ToothArrayLen The selection method is to use the diagnostic evaluation window to judge the difference between normal and abnormal engine combustion torque to be the most obvious. The main approach is that the evaluation window includes the engine IMEP reaching the maximum value if the engine is burning normally. Specifically, in this example, the starting crankshaft angle phi StartThe method for determining phi is: Start =f1(n,rho)+b CatHeat ×f2(n,rho), where b CatHeat =1, otherwise 0. Considering the catalyst ignition on the starting crankshaft angle phi Start The reason is that the engine ignition angle efficiency is too low during the catalyst ignition process, resulting in too little engine combustion torque. It is necessary to increase the evaluation window to assess whether the engine combustion is normal or not. f1(n,rho) and f2(n,rho) are determined by the engine speed and the density of the fresh air entering the cylinder respectively. The specific parameters are calibrated on the engine test bench. First, after the catalyst ignition is completed, f1(n,rho) and Cnt are calibrated. ToothArrayLen Then, f2(n,rho) and Cnt are calibrated during the catalyst light-off process. ToothArrayLen2 The specific calibration method is determined based on the following: the evaluation window and the torque estimation method described later (determining normal and abnormal engine combustion torque) ensure that the difference between normal and abnormal engine combustion torque is most obvious. If it is not obvious, the calibration can be appropriately adjusted to see if the difference can be optimized. In this embodiment, if the absolute value of the average of the ratios of the difference between the normal and abnormal engine combustion torques divided by the normal combustion torque exceeds 20%, the difference between normal and abnormal engine combustion torques is considered to meet the requirement.

[0223] Starting crankshaft angle phi Start The running time of each tooth within the length of the first tooth to the subsequent contact teeth is represented by array t ToothTimes [0,1,2,...,Cnt ToothArrayLen +3], where array t ToothTimes [0,1,2,...,Cnt ToothArrayLen +3] is the running time of the first tooth, and the Cnt ToothArrayLen +3 is the Cnt ToothArrayLen +4 teeth running time. It should be noted here that the specific calculation of the running time of more than 4 teeth beyond the evaluation window is mainly for use in the subsequent combustion torque estimation filter algorithm.

[0224] The fourth step is to calculate the running time t of each tooth. ToothTimes [0,1,2,...,Cnt ToothArrayLen +3] to filter and output the filter running time t of each tooth ToothTimesFilter [0,1,2,...,Cnt ToothArrayLen +1].

[0225] The main consideration is that the design deviation of the flywheel teeth and the accuracy of the crankshaft position sensor will cause a lot of burr signals to appear during the operation time of each tooth. These burr signals need to be eliminated before estimating the engine combustion torque, thereby improving the accuracy of the combustion torque estimation. At the same time, after the filtering algorithm, only the operation time of the extra two teeth that exceed the evaluation window after filtering needs to be calculated. Among them, when the catalyst is not in the ignition state or the ignition state is completed, Cnt ToothArrayLen =Cnt ToothArrayLen1 ; In the catalyst ignition condition, Cnt ToothArrayLen =Cnt ToothArrayLen2 .

[0226] 1) Set the initial value t of the filter time for calculating the running time of each tooth ToothTimesFilterRaw [N] = r1 × t ToothTimes [N]+r2×t ToothTimes [N-1]+r3×t ToothTimes [N-2]; where N is the array t in ToothTimes [0,1,2,...,Cnt ToothArrayLen +3] in the Nth sequence number. In particular, when N = 0 or 1, t ToothTimesFilterRaw [0] = t ToothTimes [0], t ToothTimesFilterRaw [1] = t ToothTimes [0].

[0227] Where r1, r2, and r3 add up to 1. This determination method, along with the torque estimation method described later (determining normal and abnormal engine combustion torque), maximizes the difference between normal and abnormal engine combustion torque. If it is not obvious, the calibration can be appropriately adjusted to see if the difference can be optimized. In this embodiment, if the absolute value of the average of the ratios of the difference between the normal and abnormal engine combustion torques divided by the normal combustion torque exceeds 20%, the difference between normal and abnormal engine combustion torques is considered to meet the requirement. In this example, the values ​​are 0.1708, 0.8821, and -0.0529, respectively.

[0228] 2) Based on this, N=0,1,2,…, Cnt ToothArrayLen +3 initial filter time, and the final filter running time t ToothTimesFilter [N] = t ToothTimesFilterRaw [N+2], after forming the array, becomes t ToothTimesFilter [0,1,2,...,Cnt ToothArrayLen +1].

[0229] In the fifth step, the engine speed is estimated based on the filtered running time of each tooth.

[0230] in, In this example, C1 is set to 0.000001min / (r*us).

[0231] Based on this, the engine speed array n of each tooth operation process is formed EstRpm [0,1,2,...,Cnt ToothArrayLen +1].

[0232] The sixth step is to estimate the initial value M of the torque difference of each tooth based on the engine speed during the operation of each tooth. EstTrqErrRaw [0,1,2,...,Cnt ToothArrayLen +1], the engine torque difference refers to the difference in engine torque change from the start of the current tooth operation to the end of the next tooth operation. If it is a negative value, the engine torque is increasing, and if it is a positive value, the engine torque is decreasing.

[0233] Among them, M EstTrqErrRaw [N]=C2×[(n EstRpm [N]) 2 -(n EstRpm [N-1]) 2 ], where C2 in this example is 3000Nm / (rpm) 2 .

[0234] Step 7: Initial value M of torque difference of each tooth EstTrqErrRaw [0,1,2,...,Cnt ToothArrayLen +1] to filter and output the filtered torque difference M of each tooth EstTrqErr [0,1,2,...,Cnt ToothArrayLen -1]. The main purpose is to remove the torque signal burrs, thereby improving the accuracy of combustion torque estimation.

[0235] 1) Filter initial value M of the initial value of the torque difference of each tooth EstTrqErrFilter [N] = r1 × M EstTrqErrRaw [N]+r2×M EstTrqErrRaw [N-1]+r2×M EstTrqErrRaw [N-2]. In particular, when N=0 or 1, M EstTrqErrFilter [0] = M EstTrqErrRaw [0],M EstTrqErrFilter [1]=M EstTrqErrRaw [0].

[0236] 2) Based on this, N=0,1,2,…, Cnt ToothArrayLen +3 is the initial value of the filtered torque difference of each tooth, and the final filtered torque difference M EstTrqErr [N]=M EstTrqErrFilter [N+2], after forming the array, becomes M EstTrqErr [0,1,2,...,CntToothArrayLen -1].

[0237] Step 8: Calculate the total torque variation M within the evaluation window used to estimate the engine combustion torque. TrqDetectDelta , mainly to M EstTrqErr [0,1,2,...,Cnt ToothArrayLen -1] are added. When adding, special attention should be paid to adding the non-negative and negative numbers separately first and then adding the two sums to obtain the final total torque change M. TrqDetectDelta The purpose of this is to ensure the accuracy of the accumulation algorithm. If integers and negative numbers are added, some data precision will be lost during the code operation, resulting in a loss of precision in the calculation results.

[0238] Step 9: Determine whether the engine combustion torque is abnormal.

[0239] 1) Total torque change M TrqDetectDelta Filter to obtain the total torque change M after filtering TrqSumMeanNew :M TrqSumMeanNew =(1-r TrqWeightMean )×M TrqSumMean (z)+r TrqWeightMean ×M TrqDetectDelta ; where M TrqSumMean (z) is the total torque change after filtering in the previous sampling period (especially, its initial default value is 0), and its sampling update period is 180 degrees crankshaft angle, that is, from the starting crankshaft angle phi Start At the beginning, the sampling calculation is performed again after the crankshaft rotates 180 degrees. Among them, the total torque change filter coefficient r TrqWeightMean In this example, the value is 0.05 when the catalyst is activated and 0.1 when the catalyst is not activated.

[0240] 2) Calculate the initial value S of the torque characteristic value used to evaluate whether the combustion torque is abnormal TrqDetectRaw :

[0241] S TrqDetectRaw =(1-r TrqWeightVar )×S TrqDetectRaw (z)+r TrqWeightVar ×(M TrqDetectDelta -M TrqSumMeanNew ) 2

[0242] Among them S TrqDetectRaw (z) is the initial value of the torque characteristic value of the previous sampling period (especially, its first default value is 0), and its sampling update period is defined in the same way as the sampling period described above. TrqWeightVar :

[0243] r TrqWeightVar =(1-k TrqWeightVar )×r TrqWeightVar (z)+k TrqWeightVar ×(r TrqWeightGain ×b TrqDetectErr (z)+r TrqWeightInc )

[0244] Among them, r TrqWeightVar (z) is the initial value filter coefficient of the torque characteristic value in the previous sampling period. Its sampling update period is defined in the same way as the sampling period described above. Its initial default value is 0.15. The update coefficient k TrqWeightVar In this example, the gain coefficient is 0.65 when the catalyst is activated and 0.7 when the catalyst is not activated. TrqWeightGain In this example, the catalyst is activated when it is ignited and the cumulative coefficient is 0.01 when it is not activated. TrqWeightInc In this example, the value is 0.17 when the catalyst is activated and 0.1 when the catalyst is not activated. TrqDetectErr (z) is the flag indicating whether the engine combustion torque is abnormal in the previous sampling period. If it is abnormal, it is set to 1; if it is not abnormal, it is set to 0.

[0245] 3) Initial value of torque characteristic value S TrqDetectRaw Filter and obtain the filtered torque characteristic value S TrqDetect :

[0246] S TrqDetect =(1-r TrqWeightVarFilt )×S TrqDetect (z)+r TrqWeightVar ×S TrqDetectRaw

[0247] Among them, S TrqDetect (z) is the total torque change after filtering in the previous sampling period (especially, its initial default value is 0), and its sampling update period is defined in the same way as the sampling period described above. TrqWeightVarFilt In this example, the value is 0.3 when the catalyst is activated and 0.15 when the catalyst is not activated.

[0248] 4) Determine the lower limit value M for determining the abnormality of the combustion torque TrqBoundLower :

[0249]

[0250] where k BunndLower is the lower limit deviation coefficient, k BunndLower In this example, the value is 1.8 when the catalyst is activated and 2.3 when the catalyst is not activated.

[0251] 5) Calculate the torque deviation M used to determine whether the engine combustion torque is abnormal ErrEst :

[0252] M ErrEst =M TrqDetectDelta -M TrqBoundLower

[0253] 6) Determine whether the engine combustion torque is normal.

[0254] If it appears, M ErrEst <M ErrThresh , combustion torque deviation limit M ErrThresh In this example, the speed is -0.8 Nm when the catalyst is activated and -1.2 Nm when the catalyst is not activated. TrqDetectErr Set to 1, the engine combustion torque is abnormal; otherwise b TrqDetectErr If it is 0, there is no abnormality in the engine combustion torque;

[0255] 7) Determine which cylinder of the engine has abnormal combustion.

[0256] If b TrqDetectErr If it is set to 1, it will read which cylinder is in the power stroke under the corresponding average window, indicating that the corresponding cylinder has a combustion abnormality (i.e., abnormal cylinder shutdown).

[0257] The above completes the entire description of the second abnormal cylinder deactivation and torque reduction diagnostic method.

[0258] Finally, in the above two methods of combustion abnormality verification, if the following situations occur:

[0259] (1) If the cylinder number of the combustion abnormality detected by the first method is the same as the cylinder number of the combustion abnormality detected by the second method, the combustion abnormality of the corresponding cylinder will be output; and the combustion abnormality fault judgment of the corresponding cylinder will not be performed in the subsequent vehicle driving cycle until the diagnostic instrument clears the fault.

[0260] (2) If the first method detects a cylinder number with combustion abnormality, but the second method does not detect combustion abnormality on the same cylinder number, and the number of driving cycles that occur exceeds the preset number A (5 in this example), it is characterized as combustion abnormal, and the M under the cylinder number with combustion abnormality detected by the second method is set to ErrThresh The value is updated to 1.02 times the value of the last update and is saved after the vehicle is powered off. The next time a combustion anomaly occurs, the updated value will be used for evaluation. Furthermore, no further combustion anomaly fault diagnosis will be performed for the corresponding cylinder in subsequent driving cycles until the diagnostic instrument clears the fault.

[0261] (3) If the first method detects a cylinder number with combustion abnormality, but the second method does not detect combustion abnormality on the same cylinder number, and the number of driving cycles that occur does not exceed the preset number A, then the combustion abnormality is in a pending state (the pending state means that the combustion abnormality has occurred but is not confirmed). The r under the cylinder number with combustion abnormality detected by the first method is CynDetectOffLim The update is 0.992 times the value of the last update and is updated at most once per driving cycle. Furthermore, abnormal combustion faults in the corresponding cylinders will still be detected in subsequent driving cycles.

[0262] (4) If the second method detects a cylinder number with combustion abnormality, but the first method does not detect combustion abnormality on the same cylinder number, and the number of driving cycles that occur exceeds the preset number A, it is characterized as combustion abnormality, and the r under the cylinder number with combustion abnormality detected by the first method is set to CynDetectOffLim If the value is updated to 1.02 times the value of the last update and is saved after the vehicle is powered off, the next evaluation of a combustion anomaly will be based on the updated value. Furthermore, no further combustion anomaly fault diagnosis will be performed for the corresponding cylinder in subsequent driving cycles until the diagnostic tool clears the fault.

[0263] (5) If the second method detects a cylinder number with combustion abnormality, but the first method does not detect combustion abnormality in the same cylinder number, and the number of driving cycles that occur does not exceed the preset number A, then the combustion abnormality is characterized as pending (pending means that the combustion abnormality has occurred but is not confirmed). At the same time, the M under the cylinder number of the combustion abnormality detected by the second method is ErrThresh The update is 0.992 times the last update and is updated at most once per driving cycle. The corresponding cylinder combustion abnormality fault judgment is still performed in subsequent vehicle driving cycles.

[0264] (6) If neither the first nor the second method currently detects the same cylinder combustion anomaly, the combustion anomaly is marked as pending (a pending state means that the combustion anomaly has occurred but is not confirmed). The corresponding cylinder combustion anomaly fault judgment is still performed in subsequent vehicle driving cycles.

[0265] The above completes the entire description of the method for diagnosing abnormal engine cylinder deactivation and torque reduction.

[0266] An embodiment of the present invention further provides an electronic device, Figure 4This is a schematic diagram of the structure of an electronic device provided by an embodiment of the present invention, such as a smart phone, tablet computer, laptop computer, desktop computer, rack server, blade server, tower server or cabinet server (including an independent server or a server cluster composed of multiple servers), etc. The computer electronic device 20 of this embodiment includes at least but not limited to: a memory 21 and a processor 22 that can be interconnected through a system bus, such as Figure 4 It should be pointed out that Figure 4 The electronic device 20 is shown only with components 21 - 22 , but it is understood that implementing all of the illustrated components is not a requirement, and greater or fewer components may alternatively be implemented.

[0267] In this embodiment, the memory 21 (i.e., a readable storage medium) includes flash memory, a hard disk, a multimedia card, a card-type memory (e.g., SD or DX memory), random access memory (RAM), static random access memory (SRAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), and programmable read-only memory (PROM). The memory 21 may also be an external storage device of the electronic device 20, such as a plug-in hard disk, a smart media card (SMC), a secure digital (SD) card, a flash memory card, etc. equipped on the electronic device 20. Of course, the memory 21 may also include both the internal storage unit of the electronic device 20 and its external storage device. In this embodiment, the memory 21 is generally used to store the operating system and various application software installed on the electronic device 20, such as the program code of the engine abnormal cylinder deactivation and torque reduction diagnostic method in the method embodiment. In addition, the memory 21 may also be used to temporarily store various data that has been output or is about to be output.

[0268] In some embodiments, the processor 22 can be a central processing unit (CPU), a controller, a microcontroller, a microprocessor, or other data processing chip. The processor 22 is generally used to control the overall operation of the electronic device 20. In this embodiment, the processor 22 is used to execute program code stored in the memory 21 or process data. For example, the processor 22 executes a device storing program code for a method for diagnosing abnormal engine cylinder deactivation and torque reduction, thereby implementing the method for diagnosing abnormal engine cylinder deactivation and torque reduction in the method embodiment.

[0269] The present invention also provides a computer-readable storage medium, such as a flash memory, a hard disk, a multimedia card, a card-type memory (e.g., SD or DX memory), a random access memory (RAM), a static random access memory (SRAM), a read-only memory (ROM), an electrically erasable programmable read-only memory (EEPROM), a programmable read-only memory (PROM), a magnetic storage device, a magnetic disk, an optical disk, a server, an app store, etc., storing a computer program that, when executed by a processor, implements a corresponding function. The computer-readable storage medium of this embodiment is used to store program code for a method for diagnosing abnormal engine cylinder deactivation and torque reduction, and, when executed by a processor, implements the method for diagnosing abnormal engine cylinder deactivation and torque reduction according to the method embodiment.

[0270] Those skilled in the art will appreciate that the embodiments of the present application can be provided as methods, systems, or computer program products. Therefore, the present application can adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application can adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code.

[0271] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the steps in the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0272] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0273] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0274] In summary, the present invention provides a method for diagnosing abnormal engine cylinder deactivation and torque reduction, an electronic device and a storage medium, which performs abnormal engine cylinder deactivation and torque reduction judgment by selecting different methods under different working conditions, that is, the cylinder number detected by the first method for diagnosing abnormal engine cylinder deactivation and torque reduction and the cylinder number detected by the second method for diagnosing abnormal engine cylinder deactivation and torque reduction are jointly determined to determine the cylinder number of the abnormal engine cylinder deactivation, and if the judgment results are different, the judgment threshold is continuously updated, thereby improving the judgment accuracy of abnormal engine cylinder deactivation and torque reduction, thereby reminding the driver to perform maintenance and inspection in time, and also protecting the engine in time.

[0275] It should be noted that the size of the serial numbers of the steps in the above embodiments does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0276] It should be pointed out that, according to the needs of implementation, the various steps / components described in this application can be split into more steps / components, or two or more steps / components or partial operations of steps / components can be combined into new steps / components to achieve the purpose of the present invention.

[0277] It will be easily understood by those skilled in the art that the above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for diagnosing abnormal engine cylinder deactivation and torque reduction, characterized in that: The method includes: When the engine abnormal cylinder deactivation and torque reduction diagnosis enabling conditions are met, the engine abnormal cylinder deactivation and torque reduction diagnosis is performed: When the activation conditions of the first method for diagnosing abnormal engine cylinder deactivation and torque reduction are met, the cylinder number of the abnormally deactivated cylinder is detected by the first method for diagnosing abnormal engine cylinder deactivation and torque reduction. The first method for diagnosing abnormal engine cylinder deactivation and torque reduction includes: Obtaining the operating time of each cylinder of the engine within a specific crankshaft operating angle range, and calculating the average operating time of each cylinder of the engine within a plurality of consecutive sampling periods; wherein the specific crankshaft operating angle range is the crankshaft angle from 80° after compression top dead center of each cylinder of the engine to 260° after compression top dead center of its corresponding cylinder; Divide the evaluation area according to the engine speed and determine the evaluation time update coefficient of each cylinder of the engine in each evaluation area; determining whether activation conditions for an engine abnormal cylinder deactivation diagnosis evaluation time update optimization process are met; if not, maintaining the evaluation time update coefficients of each cylinder of the engine in each evaluation area unchanged; and if so, determining a value of an evaluation time update optimization counter, and determining an initial value of the evaluation time update coefficient based on the evaluation time update coefficient and the average operating time value; Determine the value of the flag bit according to the value of the evaluation time update optimization counter, and determine the updated evaluation time update coefficient according to the value of the flag bit, the initial value of the evaluation time update coefficient and the evaluation time update coefficient; Determine a final running time according to the value of the flag bit, the updated evaluation time update coefficient, and the running time; Calculating an average value of the final operating time of each cylinder of the engine within a plurality of consecutive sampling periods according to the final operating time, and determining a maximum value and a minimum value of the average value of the final operating time; determining a value of an initial flag indicating whether a fixed cylinder is abnormally deactivated according to a maximum value and a minimum value of the final average value of the operating time; determining the cylinder number of the abnormally deactivated cylinder according to the value of the initial flag indicating whether the fixed cylinder is abnormally deactivated; When the activation condition of the second engine abnormal cylinder deactivation and torque reduction diagnostic method is met, the cylinder number of the abnormally deactivated cylinder is detected by the second engine abnormal cylinder deactivation and torque reduction diagnostic method; The cylinder number of the abnormal engine deactivation is determined by combining the cylinder number detected by the first method for diagnosing abnormal engine deactivation and torque reduction and the cylinder number detected by the second method for diagnosing abnormal engine deactivation and torque reduction with the cylinder number detected by the second method; The second method for diagnosing abnormal engine cylinder deactivation and torque reduction includes: The number of the abnormally deactivated cylinder is determined based on the total torque variation within an evaluation window for estimating the engine combustion torque.

2. The method for diagnosing abnormal engine cylinder deactivation and torque reduction according to claim 1, characterized in that: Conditions for enabling diagnosis of abnormal engine cylinder deactivation and torque reduction include: (1) Entering the fire diagnosis area specified in the regulations; (2) No request for fuel cut-off; (3) The gear position has not changed, and the first time after the gear position changes is delayed; (4) The clutch is in full engagement and the second time is delayed after the clutch is fully engaged; (5) Non-uneven road surface; (6) The water temperature is within the preset range; (7) The throttle opening fluctuates within a certain range; (8) The engine is in running state; When all the above conditions are met, the engine abnormal cylinder deactivation and torque reduction diagnosis enabling conditions are met.

3. The method for diagnosing abnormal engine cylinder deactivation and torque reduction according to claim 1, characterized in that: The activation condition of the first abnormal engine cylinder deactivation and torque reduction diagnostic method is determined by the average engine speed and average engine intake air density. The average engine speed and average engine intake air density are the average values ​​of the engine speed and engine intake air density during the current sampling period and several previous sampling periods, respectively. If the activation condition of the first engine abnormal cylinder deactivation and torque reduction diagnostic method in the current sampling period is not met, the first engine abnormal cylinder deactivation and torque reduction diagnostic method is not activated; If the activation conditions of the first engine abnormal cylinder deactivation and torque reduction diagnostic method are met in the current sampling period, and the activation conditions of the first engine abnormal cylinder deactivation and torque reduction diagnostic method in the previous sampling periods are met, then the first engine abnormal cylinder deactivation and torque reduction diagnostic method is activated; In other cases, the first engine abnormal cylinder deactivation and torque reduction diagnostic method is not activated; The activation conditions for the second engine abnormal cylinder deactivation and torque reduction diagnostic method are similar.

4. The method for diagnosing abnormal engine cylinder deactivation and torque reduction according to claim 1, characterized in that: The activation conditions for optimizing the engine abnormal cylinder deactivation diagnosis evaluation time update include: (1) The engine is in running state; (2) All cylinders of the engine are in the fuel cut-off state; (3) The engine does not directly participate in driving the vehicle; (4) The running time of each cylinder of the engine is not zero in several consecutive sampling periods; (5) The engine has no malfunction; When all of the above conditions are met, the activation conditions for the engine abnormal cylinder deactivation diagnosis evaluation time update optimization process are met.

5. The method for diagnosing abnormal engine cylinder deactivation and torque reduction according to claim 1, characterized in that: Determining a value of an evaluation time update optimization counter, and determining an initial value of an evaluation time update coefficient according to the evaluation time update coefficient and the running time average value, comprising: If any of the following conditions is met, the value of the evaluation time update optimization counter is reset to 1, and the initial value of the evaluation time update coefficient of each cylinder of the engine is reset to the evaluation time update coefficient within the current evaluation area: (1) The activation conditions for the optimization process of updating the engine abnormal cylinder deactivation diagnosis evaluation time are not met; (2) The current evaluation area changes; If both of the above conditions are not met, the value of the evaluation time update optimization counter is increased by 1 after each sampling period, and the initial value of the evaluation time update coefficient is accumulated at the same time. The accumulation method is as follows: For each cylinder of the engine, the quotient of its average operating time and the average operating time of all the cylinders of the engine is calculated in each sampling period, and the initial value of the evaluation time update coefficient accumulated in the previous sampling period is added to the inverse of the quotient to obtain the initial value of the evaluation time update coefficient accumulated in the current sampling period.

6. The method for diagnosing abnormal engine cylinder deactivation and torque reduction according to claim 1, characterized in that: Determining a flag value according to a value of an evaluation time update optimization counter, and determining an updated evaluation time update coefficient according to the flag value, the evaluation time update coefficient initial value, and the evaluation time update coefficient, including: If the evaluation time of the current evaluation area is updated, the value of the optimization counter is not less than the preset value. Number of times Greater than the preset number of times , then the flag value is 1; otherwise the flag value is 0; where, the number of times The accumulation method is: after the value of the optimization counter of the evaluation time of the current evaluation area is reset, it is accumulated again. If the value of the optimization counter of the evaluation time of the current evaluation area is not less than the preset value, , then the number of times Add 1; every time the evaluation time of the current evaluation area is updated and the optimization counter is reset, the number of times Accumulate at most once; When the flag value is 0 and the value of the evaluation time update optimization counter of the current evaluation area is not less than the preset value , updating the evaluation time update coefficient by calculating, for a cylinder in the current evaluation area, the product of the initial value of the evaluation time update coefficient and the first weighting coefficient, and simultaneously calculating the difference between 1 and the first weighting coefficient and the product of the difference and the evaluation time update coefficient corresponding to the cylinder in the current evaluation area; the sum of the two products is the updated evaluation time update coefficient; When the flag value is 1 and the value of the evaluation time update optimization counter of the current evaluation area is not less than the preset value , updating the evaluation time update coefficient by calculating, for a cylinder in the current evaluation area, the product of the initial value of the evaluation time update coefficient and the second weighting coefficient, and simultaneously calculating the difference between 1 and the second weighting coefficient and the product of the difference and the evaluation time update coefficient corresponding to the cylinder in the current evaluation area, the sum of the two products being the updated evaluation time update coefficient; wherein both the first weighting coefficient and the second weighting coefficient are less than 1, and the second weighting coefficient is not greater than the first weighting coefficient; Determining a final running time according to the value of the flag bit, the updated evaluation time update coefficient, and the running time includes: When the flag value is 0, the running time of each cylinder of the engine is the final running time; When the value of the flag bit is 1, the product of the running time of each cylinder of the engine and the corresponding updated evaluation time update coefficient is the final running time.

7. The method for diagnosing abnormal engine cylinder deactivation and torque reduction according to claim 1, characterized in that: Determining the value of an initial flag indicating whether a fixed cylinder is abnormally deactivated according to the maximum and minimum values ​​of the final average operating time includes: Determining a characteristic coefficient according to the maximum and minimum values ​​of the final running time average values ​​includes: Get the maximum value of the final running time average value in the current sampling period With minimum value , and calculate the corresponding intermediate value ; Similarly, calculate the intermediate values ​​corresponding to several sampling periods before the current sampling period, and finally calculate the average value of all intermediate values, which is the characteristic coefficient; Determining the value of an initial flag indicating whether a fixed cylinder is abnormally deactivated based on the characteristic coefficient and a preset threshold coefficient for determining whether the fixed cylinder is abnormally deactivated includes: If the characteristic coefficient is greater than or equal to the preset threshold coefficient for determining whether the fixed cylinder is abnormally deactivated, the value of the initial flag bit for determining whether the fixed cylinder is abnormally deactivated is 1, otherwise it is 0; The threshold coefficient for determining abnormal cylinder deactivation of a fixed cylinder is determined by the average engine speed and the average engine intake air density; the average engine speed and the average engine intake air density are the average values ​​of the engine speed and the engine intake air density during the current sampling period and several previous sampling periods, respectively. Determining the cylinder number of the abnormally deactivated cylinder according to the value of the initial flag indicating whether the fixed cylinder is abnormally deactivated includes: On the premise that the initial flag value of whether the fixed cylinder is continuously shut down is 1, if: Case 1: Determine the cylinder number whose average running time is equal to the maximum value; Case 2: If a cylinder satisfies the following conditions, its cylinder number is determined: first, the difference between the maximum value and the average value of the cylinder's operating time is calculated, and then the quotient of the difference and the maximum value is calculated, and the quotient is greater than zero and less than a first preset value; Case 3: The cylinder meeting the first case or the second case meets the following conditions: first, the difference between all the running time of the cylinder meeting the first case or the second case and the maximum value in a number of consecutive sampling periods is calculated, and then the quotient of these differences and the maximum value is calculated, and the quotient is less than zero and greater than a second preset value; The fourth case: at least one cylinder does not meet the first or the second case; Case 5: The following situation exists: When the cylinder numbers that meet the first or second conditions are recorded according to the cylinder working order, the number of cylinders that do not meet the first or second conditions between two consecutive cylinder numbers that meet the first or second conditions is not less than 2, and the cylinder number equal to the minimum value is not the next working cylinder number after the cylinder number that meets the first or second conditions; If the first condition, the second condition, the third condition, the fourth condition, and the fifth condition are all satisfied, it indicates that the cylinder satisfying the first condition or the second condition has abnormal cylinder deactivation.

8. The method for diagnosing abnormal engine cylinder deactivation and torque reduction according to claim 7, characterized in that: The second method for diagnosing abnormal engine cylinder deactivation and torque reduction specifically includes: Get the running time of each tooth of the engine crankshaft flywheel; determining a starting crankshaft angle and tooth length for estimating engine combustion torque, determining an evaluation window for estimating engine combustion torque based on the starting crankshaft angle and tooth length, and obtaining an array of operating times of each tooth within the evaluation window in combination with the operating times of each tooth; Filter the running time array of each tooth and output the filtered running time array of each tooth; Estimating the engine speed based on the filter running time array of each tooth to obtain an engine speed array; estimating the initial torque difference value of each tooth based on the engine speed during the operation of each tooth, and obtaining an array of initial torque difference values; Filtering the initial value array of the torque difference of each tooth and outputting the filtered torque difference array of each tooth; Calculating a total torque variation within the evaluation window based on the filtered torque difference array of each tooth; The cylinder number of the abnormally deactivated cylinder is determined according to the total torque variation.

9. The method for diagnosing abnormal engine cylinder deactivation and torque reduction according to claim 8, characterized in that: Get the running time of each tooth of the engine crankshaft flywheel, including: The running time of each tooth refers to the time required for the engine flywheel to go from the current tooth to the next tooth when running; for a missing tooth, the average of the running times of the teeth before and after the missing tooth is taken as the running time of the missing tooth.

10. The method for diagnosing abnormal engine cylinder deactivation and torque reduction according to claim 8, characterized in that: Determining a starting crankshaft angle and tooth length for estimating engine combustion torque, determining an evaluation window for estimating engine combustion torque based on the starting crankshaft angle and tooth length, and obtaining an array of operating times of each tooth within the evaluation window in combination with the operating time of each tooth, including: Starting crankshaft angle The method to determine is: ;in, The catalyst light-off control is activated. is 1, otherwise 0; and is the calibration value, which is determined by the engine speed n and the density of fresh air entering the cylinder rho Joint decision: After the catalyst is ignited, the calibration value is determined and the length of the first tooth , calibrate the calibration value during the catalyst light-off process and the second tooth length The calibration is determined based on the following: the difference between the combustion torque during abnormal cylinder deactivation and the combustion torque during normal cylinder deactivation within the evaluation window meets the preset requirements; An evaluation window for estimating the engine combustion torque is determined based on the starting crankshaft angle and the tooth length, and the evaluation window and the running time array of the four consecutive teeth after the evaluation window are obtained by combining the running time of each tooth. ; Among them, when the catalyst is not in the ignition state or the ignition state is completed, the number of teeth is ; When the catalyst is ignited, the number of teeth and length ; Filter the running time array of each tooth and output the filtered running time array of each tooth, including: Calculate the initial value of the filter time for the running time of each tooth : Where N is the running time array When N=0 or 1, , ; 、 and is a weighting coefficient, the sum of the three is 1, and the determination method is: the difference between the combustion torque when the engine is abnormally deactivated and the combustion torque when there is no abnormal cylinder deactivation within the evaluation window meets the preset requirements; Determine the filter run time for each tooth , get the filter running time array of each tooth ; The engine speed is estimated based on the filter running time array of each tooth to obtain the engine speed array, including: Calculating engine speed ; Where C1 is the coefficient; Get the engine speed array ; The initial torque difference value of each tooth is estimated based on the engine speed during the operation of each tooth, and an array of initial torque difference values ​​is obtained, including: Calculate the initial value of the torque difference of each tooth ; Where C2 is the coefficient; Get the initial value array of torque difference ; Filter the initial value array of the torque difference of each tooth and output the filtered torque difference array of each tooth, including: Similar to the running time array filtering, the filtered torque difference array is obtained .

11. The method for diagnosing abnormal engine cylinder deactivation and torque reduction according to claim 10, characterized in that: Calculating the total torque variation within the evaluation window based on the filtered torque difference array of each tooth includes: The filtered torque difference array Add up the numbers in to get the total torque change ; Determining the cylinder number of the abnormally deactivated cylinder according to the total torque change includes: Change in total torque Filter to obtain the total torque change after filtering : Where, is the total torque change after filtering in the previous sampling period; is the total torque variation filter coefficient; Calculate the initial value of the torque characteristic value used to evaluate whether the combustion torque is abnormal : in, is the initial value of the torque characteristic value of the previous sampling period; is the initial value filter coefficient of the torque characteristic value, and the calculation method is: in, is the initial value filter coefficient of the torque characteristic value of the previous sampling period; is the update coefficient; is the gain coefficient; is the cumulative coefficient; The flag indicating whether the engine combustion torque is abnormal in the previous sampling period is 1 if it is abnormal, and 0 if it is not abnormal. Initial value of torque characteristic value Filter to obtain the filtered torque characteristic value : in, is the total torque change after filtering in the previous sampling period; is the filtering coefficient of the torque characteristic value after filtering; Determine the lower limit value for determining combustion torque abnormality : in, is the coefficient of deviation of the lower limit; Calculates torque deviation to determine if engine combustion torque is abnormal : Determine whether the engine combustion torque is normal: If it appears ,but Set to 1, the engine combustion torque is abnormal; otherwise is 0, and the engine combustion torque is normal; is the combustion torque deviation limit; Determine the cylinder number of the abnormally shut down cylinder: if If set to 1, the cylinder number in the power stroke under the corresponding evaluation window is read, indicating that the corresponding cylinder has abnormally stopped.

12. The method for diagnosing abnormal engine cylinder deactivation and torque reduction according to claim 10, characterized in that: The difference between the combustion torque during abnormal cylinder deactivation and the combustion torque during normal cylinder deactivation within the evaluation window meets preset requirements, including: The difference between the combustion torque during abnormal cylinder deactivation and the combustion torque during non-abnormal cylinder deactivation is divided by the combustion torque during non-abnormal cylinder deactivation to obtain a ratio. If the absolute value of the average value of the ratio exceeds the preset ratio threshold, the preset requirement is met.

13. The method for diagnosing abnormal engine cylinder deactivation and torque reduction according to claim 11, characterized in that: The cylinder number detected by the first engine abnormal cylinder deactivation and torque reduction diagnostic method and the cylinder number detected by the second engine abnormal cylinder deactivation and torque reduction diagnostic method are used together to determine the cylinder number of the abnormal engine deactivation, including: If the cylinder number detected by the first abnormal engine deactivation and torque reduction diagnostic method is the same as the cylinder number detected by the second abnormal engine deactivation and torque reduction diagnostic method, the corresponding cylinder has been abnormally deactivated; and the abnormal deactivation fault diagnosis for the corresponding cylinder will not be performed in subsequent vehicle driving cycles until the diagnostic instrument clears the fault. If the first engine abnormal cylinder deactivation and torque reduction diagnostic method detects the cylinder number of the abnormal cylinder deactivation, but the second engine abnormal cylinder deactivation and torque reduction diagnostic method does not detect the same cylinder number as the abnormal cylinder deactivation, and the number of driving cycles that occur exceeds the preset number A, it is characterized as abnormal cylinder deactivation, and the combustion torque deviation limit of the corresponding cylinder under the second engine abnormal cylinder deactivation and torque reduction diagnostic method is set to Updated to the first multiple; and in subsequent vehicle driving cycles, abnormal cylinder deactivation fault judgment of the corresponding cylinder will not be performed until the diagnostic instrument clears the fault; If the first abnormal engine deactivation and torque reduction diagnostic method detects the cylinder number of an abnormally deactivated cylinder, but the second abnormal engine deactivation and torque reduction diagnostic method does not detect abnormal deactivation of the same cylinder number, and the number of driving cycles in which the abnormal deactivation occurs does not exceed the preset number A, then the combustion anomaly is indicated as being in a pending state, and the threshold coefficient for determining abnormal fixed cylinder deactivation for the corresponding cylinder under the first abnormal engine deactivation and torque reduction diagnostic method is updated to the second multiple, and is updated at most once per driving cycle, and abnormal cylinder deactivation fault determination for the corresponding cylinder is still performed in subsequent vehicle driving cycles; If the second engine abnormal cylinder deactivation and torque reduction diagnostic method detects the cylinder number of the abnormally deactivated cylinder, but the first engine abnormal cylinder deactivation and torque reduction diagnostic method does not detect abnormal cylinder deactivation of the same cylinder number, and the number of driving cycles in which the abnormal cylinder deactivation occurs exceeds the preset number A, then abnormal cylinder deactivation is indicated, and the threshold coefficient for determining abnormal fixed cylinder deactivation of the corresponding cylinder under the first engine abnormal cylinder deactivation and torque reduction diagnostic method is updated to the first multiple, and abnormal cylinder deactivation fault determination for the corresponding cylinder is not performed in subsequent vehicle driving cycles until the diagnostic instrument clears the fault, at which time abnormal cylinder deactivation fault determination is performed again; If the second engine abnormal cylinder deactivation and torque reduction diagnostic method detects the cylinder number of the abnormal cylinder deactivation, but the first engine abnormal cylinder deactivation and torque reduction diagnostic method does not detect the same cylinder number as the abnormal cylinder deactivation, and the number of driving cycles that occur does not exceed the preset number A, it indicates that the combustion abnormality is in an unresolved state, and the combustion torque deviation limit of the corresponding cylinder under the second engine abnormal cylinder deactivation and torque reduction diagnostic method is set to The update is a multiple of the second and is updated at most once per driving cycle, and the corresponding cylinder abnormal deactivation fault judgment is still performed in subsequent vehicle driving cycles; If the first engine abnormal cylinder deactivation and torque reduction diagnostic method and the second engine abnormal cylinder deactivation and torque reduction diagnostic method do not detect the same cylinder number, abnormal cylinder deactivation fault judgment is still performed in the subsequent vehicle driving cycle; The first multiple is greater than 1, and the second multiple is less than 1.

14. An electronic device, characterized in that: The electronic device comprises: a storage device for storing executable instructions; A processing device is used to execute the executable instructions stored in the storage device to implement the engine abnormal cylinder deactivation and torque reduction diagnosis method according to any one of claims 1 to 13.

15. A storage medium, characterized in that: The storage medium stores a computer program, and when the computer program is executed, the method for diagnosing abnormal cylinder deactivation and torque reduction of an engine according to any one of claims 1 to 13 is implemented.

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