Engine abnormal cylinder deactivation and torque reduction diagnosis method, electronic equipment and storage medium

Abstract

The invention discloses an engine abnormal cylinder deactivation and torque reduction diagnosis method, electronic equipment and a storage medium, and the method comprises the steps: carrying out engine abnormal cylinder deactivation and torque reduction diagnosis when an engine abnormal cylinder deactivation and torque reduction diagnosis enabling condition is satisfied; the cylinder number of abnormal cylinder deactivation is detected through a first engine abnormal cylinder deactivation torque reduction diagnosis method; when the activation condition of the second engine abnormal cylinder deactivation and torque reduction diagnosis method is met, the cylinder number of abnormal cylinder deactivation is detected through the second engine abnormal cylinder deactivation and torque reduction diagnosis method; and the cylinder number of the abnormal cylinder deactivation of the engine is jointly determined according to the cylinder numbers detected by the first engine abnormal cylinder deactivation torque reduction diagnosis method and the second engine abnormal cylinder deactivation torque reduction diagnosis method. Different methods are selected under different working conditions for abnormal cylinder deactivation and torque reduction judgment, judgment is performed according to the two results, the engine abnormal cylinder deactivation and torque reduction judgment precision is improved, and therefore a driver can be reminded to conduct maintenance and detection in time, and the engine is protected.

Description

Technical Field

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

[0002] If the engine stops the cylinders and reduces the torque abnormally, it will have adverse consequences on the engine power, emission and economy if it is not identified in time. Therefore, it is necessary to diagnose and identify whether the engine stops the cylinders and reduces the torque abnormally, so as to remind the driver to repair and inspect in time and protect the engine in time. Summary of the invention

[0003] The purpose of the present invention is to provide a method for diagnosing abnormal engine cylinder deactivation and torque reduction, an electronic device and a storage medium for diagnosing and identifying whether the engine has abnormal cylinder deactivation and torque reduction, thereby reminding the driver to perform maintenance and inspection in time to protect the engine.

[0004] To achieve the above object, according to a first aspect of the present invention, a method for diagnosing abnormal cylinder deactivation and torque reduction of an engine 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 condition of the first engine abnormal cylinder deactivation and torque reduction diagnostic method is met, the cylinder number of the abnormal cylinder deactivation is detected by the first engine abnormal cylinder deactivation and torque reduction diagnostic method; wherein the first engine abnormal cylinder deactivation and torque reduction diagnostic method includes:

[0007] Obtain the running time of each cylinder of the engine in a specific crankshaft running angle, and calculate the average running time of each cylinder of the engine in a number of consecutive sampling periods; wherein the specific crankshaft running angle is the crankshaft angle of each cylinder of the engine from 80° after the cylinder compression top dead center to 260° after the corresponding cylinder compression top dead center;

[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] Determine whether the activation conditions for the engine abnormal cylinder stop diagnosis evaluation time update optimization process are met; if not, the evaluation time update coefficients of each cylinder of the engine in each evaluation area remain unchanged; if so, determine the value of the evaluation time update optimization counter, and determine the initial value of the evaluation time update coefficient according to the evaluation time update coefficient and the average value of the running time;

[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 evaluation time update coefficient initial value 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 running time of each cylinder of the engine in a plurality of consecutive sampling periods according to the final running time, and determining a maximum value and a minimum value of the average value of the final running time;

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

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

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

[0016] The cylinder number of the abnormal engine cylinder deactivation is determined by jointly using 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.

[0017] In the above scheme, the engine abnormal cylinder stop torque reduction diagnosis enabling conditions include:

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

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

[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 operation;

[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 engine abnormal cylinder deactivation and torque reduction diagnosis method is jointly determined by the average engine speed and the average engine intake density; wherein the average engine speed and the average engine intake density are respectively the average values ​​of the engine speed and the engine intake density of the current sampling period and several 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 in the current sampling cycle are met, and the activation conditions of the first engine abnormal cylinder deactivation and torque reduction diagnostic method in the previous sampling cycles 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 scheme, the activation conditions of the engine abnormal cylinder deactivation diagnosis evaluation time update optimization process include:

[0033] (1) The engine is in operation;

[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 in several consecutive sampling periods is not zero;

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

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

[0040] In the above scheme, 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 running time average value, includes:

[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 engine abnormal cylinder deactivation diagnosis evaluation time update optimization process are not met;

[0043] (2) The current evaluation area changes;

[0044] If both of the above two 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 running time average value and the average of the running time average values ​​of all the cylinders of the engine is calculated in each sampling cycle, and the initial value of the evaluation time update coefficient accumulated in the previous sampling cycle is added to the reciprocal of the quotient to obtain the initial value of the evaluation time update coefficient accumulated in the current sampling cycle.

[0046] In the above scheme, the value of the flag 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, 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 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; each 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 the product of the initial value of the evaluation time update coefficient and the first weighting coefficient for a cylinder in the current evaluation area, and 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, and 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: for a cylinder in the current evaluation area, calculating the product of the initial value of the evaluation time update coefficient and the second weighting coefficient, and 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, and the sum of the two products is the updated evaluation time update coefficient; wherein the first weighting coefficient and the second weighting coefficient are both 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 value of the flag 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 operating time of each cylinder of the engine and the corresponding updated evaluation time update coefficient is the final operating time.

[0053] In the above scheme, determining the value of the initial flag bit of whether the fixed cylinder is abnormally deactivated or not according to the maximum value and the minimum value of the final running time average value includes:

[0054] Determine a characteristic coefficient according to the maximum value and the minimum value of the final running time average value, including:

[0055] Get the maximum value T of the final running time average value 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 bit indicating whether the 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 respectively the average values ​​of the engine speed and the engine intake air density of the current sampling period and the previous sampling periods;

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

[0061] On the premise that the value of the initial flag bit 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] The second case: if a cylinder meets the following conditions, then its cylinder number is determined: first, the difference between the maximum value and the average value of the operation time of the cylinder 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] The third case: the cylinder that meets the first case or the second case meets the following conditions: firstly, the difference between all the running time of the cylinder that meets the first case or the second case and the maximum value in a number of consecutive sampling cycles 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 satisfy the first case or the second case;

[0066] The fifth case: the following case exists: when the cylinder numbers satisfying the first or second case are recorded according to the cylinder working order, between two consecutive cylinder numbers satisfying the first or second case, the number of cylinders not satisfying the first or second case is not less than 2, and the cylinder number equal to the minimum value is not the next working cylinder number of the cylinder number satisfying the first or second case;

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

[0068] In the above scheme, 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] Determine a starting crankshaft angle and a tooth length for estimating the engine combustion torque, determine an evaluation window for estimating the engine combustion torque according to the starting crankshaft angle and the tooth length, and obtain an array of running times of each tooth within the evaluation window in combination with the running time of each tooth;

[0071] Filtering the running time array of each tooth, and outputting the filtered running time array of each tooth;

[0072] The engine speed is estimated based on the filter operation time array of each tooth to obtain an engine speed array;

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

[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 the 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 scheme, the running time of each tooth of the engine crankshaft flywheel is obtained, including:

[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 the starting crankshaft angle and tooth length for estimating the engine combustion torque, determining the evaluation window for estimating the engine combustion torque according to the starting crankshaft angle and tooth length, and obtaining the running time array of each tooth in the evaluation window in combination with the running time of each tooth, includes:

[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 fresh air density rho entering the cylinder: 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 light-off process ToothArrayLen2 ,The calibration is determined based on: the difference between the combustion torque when the engine is abnormally deactivated and the combustion torque when the engine is not abnormally deactivated within the evaluation window meets the preset requirements;

[0081] An evaluation window for estimating the engine combustion torque is determined according to the starting crankshaft angle and the tooth length, and the evaluation window and the running time array t of four consecutive teeth after the evaluation window are obtained in combination with the running time of each tooth. ToothTimes [0,1,2,...,Cnt ToothArrayLen +3]; where, 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 t of the filter time 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, and the determination method is: the difference between the combustion torque when the engine is abnormally deactivated and the combustion torque when the engine is not abnormally deactivated 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 of 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] Calculate engine speed Among them, C1 is the coefficient;

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

[0090] The initial value of the torque difference of each tooth is estimated based on the engine speed during the operation of each tooth, and an array of initial values ​​of the torque difference 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 initial value array M of the torque difference EstTrqErrRaw [0,1,2,...,Cnt ToothArrayLen +1];

[0093] The initial value array of the torque difference of each tooth is filtered, and the filtered torque difference array of each tooth is output, 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], and the total torque change M is obtained by adding the numbers in 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 q W eight M ean is the total torque change filtering 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 q 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 q 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 bit for whether the engine combustion torque is abnormal in the previous sampling period. If it is abnormal, it is 1; if it is not abnormal, it is 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 lower limit deviation coefficient;

[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 stopped cylinder:

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

[0118] In the above scheme, the difference between the combustion torque when the engine is abnormally deactivated and the combustion torque when the engine is not abnormally deactivated 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 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 engine abnormal cylinder deactivation, including:

[0122] If the cylinder number detected by the first engine abnormal cylinder deactivation and torque reduction diagnostic method is the same as the cylinder number detected by the second engine abnormal cylinder deactivation and torque reduction diagnostic method, the corresponding cylinder is abnormally deactivated; and the corresponding cylinder abnormal cylinder deactivation fault judgment is no longer performed in the subsequent vehicle driving cycle until the diagnostic instrument clears the fault and then the abnormal cylinder deactivation fault judgment is performed again;

[0123] If the first engine abnormal cylinder deactivation and torque reduction diagnostic method detects the cylinder number of abnormal cylinder deactivation, but the second 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 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 the subsequent vehicle driving cycle, the abnormal cylinder deactivation fault judgment of the corresponding cylinder is no longer performed until the diagnostic instrument clears the fault and then the abnormal cylinder deactivation fault judgment is performed again;

[0124] If the first engine abnormal cylinder deactivation and torque reduction diagnostic method detects the cylinder number of abnormal cylinder deactivation, but the second 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 that occur does not exceed the preset number A, it is characterized that the combustion abnormality is in a pending state, and the threshold coefficient for determining abnormal cylinder deactivation of the fixed cylinder under the first engine abnormal cylinder deactivation and torque reduction diagnostic method is updated to the second multiple, and is updated at most once per driving cycle, and the corresponding cylinder abnormal cylinder deactivation fault determination 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 abnormal cylinder deactivation, 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 that occur exceeds the preset number A, it is characterized as abnormal cylinder deactivation, and the threshold coefficient for determining abnormal 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 of the corresponding cylinder is no longer performed in subsequent vehicle driving cycles until the diagnostic instrument clears the fault and then 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 abnormal cylinder deactivation, 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 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 Updated to a multiple of the second, and updated at most once per driving cycle, and abnormal cylinder deactivation fault judgment of the corresponding cylinder 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 both fail to detect the same cylinder number, abnormal cylinder deactivation fault judgment is still performed in the subsequent vehicle driving cycle;

[0128] Among them, 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, there is provided a storage medium storing a computer program, which, when executed, implements the method for diagnosing abnormal cylinder deactivation and torque reduction of an engine as described in any of the above technical solutions.

[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 engine abnormal engine cylinder deactivation and torque reduction diagnostic method and the cylinder number detected by the second engine 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 maintenance and inspection in time 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, 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; 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 cylinder deactivation and torque reduction of an engine 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 diagram of the structure of an electronic device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0138] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain 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 can 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 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, and do not indicate or imply that the referred device or element 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] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0141] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0142] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

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

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

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

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

[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 operation.

[0153] When all the above conditions are met, the engine abnormal cylinder stop torque reduction diagnosis enabling conditions are met. After all the above conditions are met for a certain period of time, the engine abnormal cylinder stop check can be performed. When the above conditions are not met, the vehicle's operating conditions may cause the engine abnormal cylinder stop check to be misjudged.

[0154] Figure 2This is the first diagnostic method for judging abnormal engine cylinder deactivation and torque reduction. As shown in Table 1, it is mainly determined by the average engine speed and the average engine intake density, and is mainly tested and verified on the engine bench by actively controlling the oil cut-off. The average engine speed and average intake density are the average values ​​of the current sampling cycle and the previous 4 times, a total of five sampling cycles, so they will be updated in real time. The sampling cycle is 180° of crankshaft rotation, and each cylinder is from the crankshaft angle of 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, after the life cycle of the engine combustion system, the operating time may be offset in different cylinders and different working 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 average running time of the corresponding cylinder in the previous A times (A is 9 in this example), totaling A+1 times (10 times in this example). Since the number of cylinders in this example is 4, for the sake of convenience, the following will take the 4-cylinder engine as an example. 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 of the first cylinder, and so on. It is particularly important to note that the default initial value of the first A running times is 0. The running time update cycle (sampling cycle) is 180° crankshaft rotation, and each cylinder is from 80° 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 is to update the optimization processing of abnormal cylinder deactivation diagnosis evaluation time to activate the condition judgment method. In this example, the update verification cycle of the condition judgment is 10ms. It can only be performed when all the following conditions are met. It is mainly when all cylinders of the engine request fuel cut-off. At this time, the evaluation time is learned and updated during the engine running process and the vehicle coasting process. 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 a number of 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, the third step is performed. Otherwise, the update coefficient r of abnormal cylinder deactivation diagnosis evaluation time is n [0,1,2,...,9] are not updated and remain unchanged. After entering the third step, in all steps, the update period (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.

[0170] The third step is to determine the update array for optimizing the abnormal cylinder deactivation diagnosis evaluation time update. That is, the evaluation time update coefficient is stored in different areas, and 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 can be saved after the vehicle is powered off, and its initial value is 1. Among them, r1[0,1,2,...] refers to the evaluation time update coefficient of the first cylinder. In this example, 10 areas are divided according to the engine speed, so the evaluation time update coefficient of the first cylinder in this example is r1[0,1,2,...,9], and the same applies to other cylinders. Specifically, in this example, 10 areas are divided according to the 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 area is 0; if the engine speed is greater than 750 rpm and less than 1000 rpm, the evaluation area is 1; and so on. It should be noted that in this example, each speed interval of each cylinder, that is, the evaluation area, 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 is met, Cnt AdaptCounter Reset to 1, and update the evaluation time coefficient to the 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 that 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 initial value r of the evaluation time update 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 in the current evaluation area has completed the first update. If the first update has not been completed, the evaluation time is accumulated in a weighted manner. The purpose of this design is that when the first update is not completed, the learning parameters are not stable, and the weighted approach is more stable and accurate.

[0182] If the abnormal cylinder deactivation diagnosis evaluation time in the current evaluation area is updated and optimized, the 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 the flag bit b FirstAdaptDone When it is 0, the counter Cnt of abnormal cylinder deactivation diagnosis evaluation time update optimization AdaptCounter Not less than the preset value Cnt A1 Only when the evaluation time update coefficient r is allowed to be updated n [0,1,2,...,9]. Otherwise, in the flag bit b FirstAdaptDone When it is 0, updating the evaluation time update coefficient r is not allowed 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 update optimization 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 × 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 of ​​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 updated in other areas, the coefficient r n , that is, forming 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 update optimization AdaptCounter Not less than the preset value Cnt A2 Time (Cnt A2 Not less than Cnt A1 The main purpose is that the evaluation time is more stable at this time, and the update speed can be slower. In this example, 16) is taken 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, updating the evaluation time update coefficient r is not allowed 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 update optimization 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 × 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 of ​​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) 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 updated in other areas, the coefficient r n , that is, forming r n [0,1,2,...,9].

[0195] The sixth step is to determine the final evaluation time for abnormal cylinder deactivation diagnosis.

[0196] 1) In the flag bit b FirstAdaptDone When T is 0, 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 the 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 area 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] Step 7: Calculate the average operating time of each cylinder within N consecutive time periods (5 in this example), calculate each cylinder separately, and form the average operating time T of each cylinder. n_Avg :

[0199]

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

[0204] 1) Determine the characteristic coefficient r used to judge abnormal cylinder deactivation of fixed cylinders CynDetectRaw :Get the current sampling period The average value of the five sampling periods together with 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 is the threshold coefficient for judging abnormal cylinder deactivation of a fixed cylinder, which is jointly determined by the average engine speed and the average engine intake density, where the average engine speed and the average engine intake 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 stopped CynOff .

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

[0208] (1) Read T n_AvgWhich cylinder has the same average running time as T Max If they are equal, determine their cylinder number;

[0209] (2) If T Max With T n_Avg The difference between the average operating time of the cylinder and the average operating time of the cylinder 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 satisfies the first or second case 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 in the order of cylinder work. If the number of cylinders that do not appear in the first or second case between two consecutive cylinder numbers that meet the first or second case is not less than 2, the cylinder number T in this 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 case or the second case. For example, assuming that the engine is a 4-cylinder engine, the cylinder working order is 1-3-4-2-1-3-4-2-…, the cylinder numbers that meet the first case or the 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 judging abnormal engine cylinder deactivation and torque reduction. As shown in Table 3, it is also mainly determined by the average engine speed and the average engine intake density, which is mainly verified by active forced oil cut-off testing on the engine bench. The average engine speed and average intake density are the average values ​​of the current sampling cycle and the previous 4 times, a total of five sampling cycles, so they will be updated in real time. The sampling cycle is 180° of crankshaft rotation, and each cylinder is from the crankshaft angle of 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 method for judging abnormal engine cylinder deactivation and torque reduction diagnosis

[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 on the flywheel plus 2 missing teeth. 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 it is running. The time from the rising edge of the current tooth to 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 tooth) to be 0. However, the tooth running time is an important parameter, which 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 followed, 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 estimating the engine combustion torque. 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 method is that if the engine is burning normally, the engine IMEP reaches the maximum value. Specifically, the starting crankshaft angle phi in this example StartThe method for determining phi is: Start =f1(n,rho)+b CatHeat ×f2(n,rho), where b CatHeat is 1, otherwise it is 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 evaluate whether the engine combustion is normal. f1(n,rho) and f2(n,rho) are determined by the engine speed and the density of fresh air entering the cylinder. The specific parameters are calibrated on the engine 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 evaluation window and the torque estimation method described later (determining the normal and abnormal engine combustion torque) can make the difference between the normal and abnormal engine combustion torque most obvious. If it is not obvious, the calibration is appropriately adjusted to see whether the difference can be optimized. In this embodiment, the absolute value of the average value of the ratio obtained by dividing the difference between the normal and abnormal engine combustion torque by the normal combustion torque exceeds 20%, then it is considered that the difference between the normal and abnormal engine combustion torque meets the requirement.

[0223] Starting crankshaft angle phi Start The running time of each tooth within the length of the first tooth after 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 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 in the running time of each tooth, which need to be eliminated to estimate the engine combustion torque, thereby improving the accuracy of the combustion torque estimation. At the same time, after the filtering algorithm, only the running 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 condition or the ignition condition is completed, Cnt ToothArrayLen =Cnt ToothArrayLen1 ; During the catalyst light-off 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. The determination method and the torque estimation method described later (determining normal and abnormal engine combustion torque) can make the difference between normal and abnormal engine combustion torque the most obvious. If it is not obvious, the calibration can be adjusted appropriately to see if the difference can be optimized. In this embodiment, the absolute value of the average value of the ratio obtained by dividing the difference between the normal and abnormal engine combustion torque by the normal combustion torque exceeds 20%, and it is considered that the difference between normal and abnormal engine combustion torque meets the requirements. In this example, 0.1708, 0.8821, and -0.0529 are taken 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 an 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 taken as 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] Step 6: Estimate the initial torque difference M 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 beginning 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 initial value of 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 an array, becomes M EstTrqErr [0,1,2,...,CntToothArrayLen -1].

[0237] Step 8: Calculate the total torque variation M in 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 numbers 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 an integer and a negative number are added, some data precision will be lost during the code operation, resulting in a loss of precision in the calculation result.

[0238] The ninth step is to 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 first 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 by light-off, and is 0.1 when the catalyst is not activated by light-off.

[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] Where 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. Among them, the torque characteristic value initial value filter coefficient r 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 it is 0.012 when it is not activated. The cumulative coefficient r 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 bit for whether the engine combustion torque is abnormal in the previous sampling cycle. If it is abnormal, it is 1; if it is not abnormal, it is 0.

[0245] 3) Initial value S of torque characteristic value 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 first 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 by light-off, and is 0.15 when the catalyst is not activated by light-off.

[0248] 4) Determine the combustion torque abnormality judgment lower limit value M 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, when the catalyst is activated, it is -0.8Nm, and when the catalyst is not activated, it is -1.2Nm. TrqDetectErr Set to 1, the engine combustion torque is abnormal; otherwise b TrqDetectErr is 0, and the engine combustion torque is normal;

[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, which indicates that the corresponding cylinder has abnormal combustion (i.e. abnormal cylinder shutdown).

[0257] The above completes the entire description of the second abnormal cylinder deactivation and torque reduction diagnosis 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 corresponding cylinder will be output as having a combustion abnormality; and the corresponding cylinder combustion abnormality fault judgment 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 in the same cylinder number, and the number of driving cycles that occur exceeds a preset number A (5 in this example), then 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 update is 1.02 times of the last update; and they are all saved after the vehicle is powered off, so the evaluation will be based on the updated one when the next combustion abnormality occurs. And in the subsequent vehicle driving cycle, the corresponding cylinder combustion abnormality fault judgment will not be performed 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 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 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 of the last update, and is updated at most once per driving cycle. In the subsequent vehicle driving cycles, the corresponding cylinder combustion abnormality fault judgment is still performed.

[0262] (4) 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 exceeds the preset number A, then 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 of the last update and is saved after the vehicle is powered off, the next time a combustion abnormality occurs, the evaluation will be based on the updated value. In the subsequent vehicle driving cycle, the corresponding cylinder combustion abnormality fault judgment will not be performed until the diagnostic instrument 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 in a pending state (the pending state means that the combustion abnormality has occurred but is not confirmed). At the same time, the M under the cylinder number with combustion abnormality detected by the second method is ErrThresh It is updated to 0.992 times of the last update and is updated at most once per driving cycle. In addition, abnormal combustion fault judgment of the corresponding cylinder is still performed in subsequent vehicle driving cycles.

[0264] (6) If the first and second methods do not detect the same cylinder combustion abnormality at present, the combustion abnormality is characterized as pending (pending means that the combustion abnormality has occurred but is not confirmed). And the corresponding cylinder combustion abnormality fault judgment is still performed in the subsequent vehicle driving cycle.

[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 41 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) that can execute programs. The computer electronic device 20 of this embodiment includes at least but is not limited to: a memory 21 and a processor 22 that can communicate with each other through a system bus, such as Figure 4 It should be pointed out that Figure 4 Only an electronic device 20 having components 21 - 22 is shown, but it should be understood that implementing all of the components shown is not a requirement, and more or fewer components may alternatively be implemented.

[0267] In this embodiment, the memory 21 (i.e., readable storage medium) includes flash memory, hard disk, multimedia card, card-type memory (e.g., SD or DX memory, etc.), random access memory (RAM), static random access memory (SRAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), programmable read-only memory (PROM). The memory 21 can also be an external storage device of the electronic device 20, such as a plug-in hard disk, a smart memory card (SmartMedia Card, SMC), a secure digital (Secure Digital, SD) card, a flash card (Flash Card), etc. equipped on the electronic device 20. Of course, the memory 21 can 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 in the electronic device 20, such as the program code of the abnormal engine cylinder deactivation and torque reduction diagnosis method in the method embodiment. In addition, the memory 21 can also be used to temporarily store various data that have been output or are to be output.

[0268] The processor 22 may be a central processing unit (CPU), a controller, a microcontroller, a microprocessor, or other data processing chips in some embodiments. 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 run the program code stored in the memory 21 or process data, such as running a device storing the program code of the engine abnormal cylinder deactivation and torque reduction diagnosis method to implement the engine abnormal cylinder deactivation and torque reduction diagnosis method 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., an SD or DX memory, etc.), 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 memory, a disk, an optical disk, a server, an App application store, etc., on which a computer program is stored, and the program realizes corresponding functions when executed by a processor. The computer-readable storage medium of this embodiment is used to store the program code of the engine abnormal cylinder deactivation and torque reduction diagnosis method, and when executed by the processor, the engine abnormal cylinder deactivation and torque reduction diagnosis method of the method embodiment is realized.

[0270] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may 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 may adopt the form of a computer program product implemented in one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that include 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 generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. 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 capable of directing a computer or other programmable data processing device to operate 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 A 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 operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified 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 selects different methods under different working conditions to perform abnormal engine cylinder deactivation and torque reduction judgments, 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 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, 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 the present 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, and 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 only 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 protection scope 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 condition of the first engine abnormal cylinder deactivation and torque reduction diagnostic method is met, the cylinder number of the abnormal cylinder deactivation is detected by the first engine abnormal cylinder deactivation and torque reduction diagnostic method; wherein the first engine abnormal cylinder deactivation and torque reduction diagnostic method includes: Obtain the running time of each cylinder of the engine in a specific crankshaft running angle, and calculate the average running time of each cylinder of the engine in a number of consecutive sampling periods; wherein the specific crankshaft running angle is the crankshaft angle of each cylinder of the engine from 80° after the cylinder compression top dead center to 260° after the corresponding cylinder compression top dead center; 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; Determine whether the activation conditions for the engine abnormal cylinder stop diagnosis evaluation time update optimization process are met; if not, the evaluation time update coefficients of each cylinder of the engine in each evaluation area remain unchanged; if so, determine the value of the evaluation time update optimization counter, and determine the initial value of the evaluation time update coefficient according to the evaluation time update coefficient and the average value of the running time; 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 evaluation time update coefficient initial value 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 running time of each cylinder of the engine in a plurality of consecutive sampling periods according to the final running time, and determining a maximum value and a minimum value of the average value of the final running time; Determining the value of an initial flag indicating whether a fixed cylinder is abnormally deactivated according to the maximum value and the minimum value of the final running time average value; Determining the cylinder number of the abnormally deactivated cylinder according to the value of the initial flag bit of whether the fixed cylinder is abnormally deactivated; When the activation condition of the second engine abnormal cylinder deactivation and torque reduction diagnosis method is met, the cylinder number of the abnormal cylinder deactivation is detected by the second engine abnormal cylinder deactivation and torque reduction diagnosis method; The cylinder number of the abnormal engine cylinder deactivation is determined by jointly using 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.

2. The method for diagnosing abnormal engine cylinder deactivation and torque reduction according to claim 1, characterized in that: The engine abnormal cylinder deactivation and torque reduction diagnosis enabling conditions 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 a fully engaged state, and the clutch is delayed for a second time after being 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 operation; 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 diagnosis method is jointly determined by the average engine speed and the average engine intake density; wherein the average engine speed and the average engine intake density are respectively the average values ​​of the engine speed and the engine intake density of the current sampling period and several previous sampling periods; 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 in the current sampling cycle are met, and the activation conditions of the first engine abnormal cylinder deactivation and torque reduction diagnostic method in the previous sampling cycles 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 the updated optimization of the engine abnormal cylinder deactivation diagnosis evaluation time include: (1) The engine is in operation; (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 engine does not experience knock or pre-ignition; (5) The running time of each cylinder of the engine in several consecutive sampling periods is not zero; (6) The engine has no malfunction; When all the above conditions are met, the activation conditions for the engine abnormal cylinder deactivation diagnosis evaluation time update optimization processing 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 engine abnormal cylinder deactivation diagnosis evaluation time update optimization process are not met; (2) The current evaluation area changes; If both of the above two 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 running time average value and the average of the running time average values ​​of all the cylinders of the engine is calculated in each sampling cycle, and the initial value of the evaluation time update coefficient accumulated in the previous sampling cycle is added to the reciprocal of the quotient to obtain the initial value of the evaluation time update coefficient accumulated in the current sampling cycle.

6. The method for diagnosing abnormal engine cylinder deactivation and torque reduction according to claim 1, characterized in that: Determining the value of a flag bit according to the value of the evaluation time update optimization counter, and determining an updated evaluation time update coefficient according to the value of the flag bit, the evaluation time update coefficient initial value and the evaluation time update coefficient, including: 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 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; each 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; 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 the product of the initial value of the evaluation time update coefficient and the first weighting coefficient for a cylinder in the current evaluation area, and 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, and 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 Cnt A2 , updating the evaluation time update coefficient by: for a cylinder in the current evaluation area, calculating the product of the initial value of the evaluation time update coefficient and the second weighting coefficient, and 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, and the sum of the two products is the updated evaluation time update coefficient; wherein the first weighting coefficient and the second weighting coefficient are both 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 value of the flag 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 operating time of each cylinder of the engine and the corresponding updated evaluation time update coefficient is the final operating 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 value and the minimum value of the final running time average value includes: Determine a characteristic coefficient according to the maximum value and the minimum value of the final running time average value, including: Get the maximum value T of the final running time average value in the current sampling period Max With the minimum value T Min , 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 bit indicating whether the 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 respectively the average values ​​of the engine speed and the engine intake air density of the current sampling period and the previous sampling periods; Determining the cylinder number of the abnormally deactivated cylinder according to the value of the initial flag bit of whether the fixed cylinder is abnormally deactivated includes: On the premise that the value of the initial flag bit of whether the fixed cylinder is continuously disconnected is 1, if: Case 1: Determine the cylinder number whose average running time is equal to the maximum value; The second case: if a cylinder meets the following conditions, then its cylinder number is determined: first, the difference between the maximum value and the average value of the operation time of the cylinder 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; The third case: the cylinder that meets the first case or the second case meets the following conditions: firstly, the difference between all the running time of the cylinder that meets the first case or the second case and the maximum value in a number of consecutive sampling cycles 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 satisfy the first case or the second case; The fifth case: the following case exists: when the cylinder numbers satisfying the first or second case are recorded according to the cylinder working order, between two consecutive cylinder numbers satisfying the first or second case, the number of cylinders not satisfying the first or second case is not less than 2, and the cylinder number equal to the minimum value is not the next working cylinder number of the cylinder number satisfying the first or second case; If the first situation, the second situation, the third situation, the fourth situation, and the fifth situation are all satisfied, it indicates that the cylinder satisfying the first situation or the second situation 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 includes: Get the running time of each tooth of the engine crankshaft flywheel; Determine a starting crankshaft angle and a tooth length for estimating the engine combustion torque, determine an evaluation window for estimating the engine combustion torque according to the starting crankshaft angle and the tooth length, and obtain an array of running times of each tooth within the evaluation window in combination with the running time of each tooth; Filtering the running time array of each tooth, and outputting the filtered running time array of each tooth; The engine speed is estimated based on the filter operation time array of each tooth to obtain an engine speed array; estimating the initial value of the torque difference of each tooth based on the engine speed during the operation of each tooth, and obtaining an array of the initial value of the torque difference; Filtering the initial value array of the torque difference of each tooth, and outputting the filtered torque difference array of each tooth; Calculating the 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 a tooth length for estimating the engine combustion torque, determining an evaluation window for estimating the engine combustion torque according to the starting crankshaft angle and the tooth length, and obtaining an array of running times of each tooth within the evaluation window in combination with the running time of each tooth, including: Starting crankshaft angle phi Start The method for determining phi is: Start =f1(n,rho)+b CatHeat ×f2(n,rho); where b CatHeat The catalyst light-off control is activated. CatHeat 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 fresh air density rho entering the cylinder: After the catalyst is ignited, the calibration value f1(n,rho) and the first tooth length Cnt are calibrated ToothArrayLen1 , during the catalyst light-off process, the calibration value f2(n,rho) and the second tooth length Cnt are calibrated ToothArrayLen2 ,The calibration is determined based on: the difference between the combustion torque when the engine is abnormally deactivated and the combustion torque when the engine is not abnormally deactivated within the evaluation window meets the preset requirements; An evaluation window for estimating the engine combustion torque is determined according to the starting crankshaft angle and the tooth length, and the evaluation window and the running time array t of four consecutive teeth after the evaluation window are obtained in combination with the running time of each tooth. ToothTimes [0,1,2,...,Cnt ToothArrayLen +3]; where, 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 ; Filter the running time array of each tooth and output the filtered running time array of each tooth, including: Calculate the initial value t of the filter time for the running time of each tooth ToothTimesFilterRaw [N]: t ToothTimesFilterRaw [N]=r1×t ToothTimes [N]+r2×t ToothTimes [N-1]+r3×t ToothTimes [N-2] 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, and the determination method is: the difference between the combustion torque when the engine is abnormally deactivated and the combustion torque when the engine is not abnormally deactivated within the evaluation window meets the preset requirements; Determine the filter run time t for each tooth ToothTimesFilter [N] = t ToothTimesFilterRaw [N+2], get the filter running time array t of each tooth ToothTimesFilter [0,1,2,...,Cnt ToothArrayLen +1]; The engine speed is estimated based on the filter running time array of each tooth to obtain the engine speed array, including: Calculate engine speed Among them, C1 is the coefficient; Get the engine speed array n EstRpm [0,1,2,...,Cnt ToothArrayLen +1]; The initial value of the torque difference of each tooth is estimated based on the engine speed during the operation of each tooth, and an array of initial values ​​of the torque difference is obtained, including: 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; Get the initial value array M of the torque difference EstTrqErrRaw [0,1,2,...,Cnt ToothArrayLen +1]; The initial value array of the torque difference of each tooth is filtered, and the filtered torque difference array of each tooth is output, including: Similar to the running time array filtering, the filtered torque difference array M is obtained EstTrqErr [0,1,2,...,Cnt ToothArrayLen -1].

11. The method for diagnosing abnormal engine cylinder deactivation and torque reduction according to claim 10, characterized in that: The total torque variation within the evaluation window is calculated based on the filtered torque difference array of each tooth, including: The filtered torque difference array M EstTrqErr [0,1,2,...,Cnt ToothArrayLen -1], and the total torque change M is obtained by adding the numbers in TrqDetectDelta ; Determining the cylinder number of the abnormally deactivated cylinder according to the total torque change includes: The 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; r TrqWeightMean is the total torque change filtering coefficient; Calculate the initial value S of the torque characteristic value used to evaluate whether the combustion torque is abnormal TrqDetectRaw : S TrqDetectRaw =(1-r TrqWeightVar )×S TrqDetectRaw (z)+r TrqWeightVar ×(M TrqDetectDelta -M TrqSumMeanNew ) 2 Among them, S TrqDetectRaw (z) is the initial value of the torque characteristic value in the previous sampling period; r TrqWeightVar is the initial value filter coefficient of the torque characteristic value, and the calculation method is: r TrqWeightVar =(1-k TrqWeightVar )×r TrqWeightVar (z)+k TrqWeightVar ×(r TrqWeightGain ×b TrqDetectErr (z)+r TrqWeightInc ) Among them, r TrqWeightVar (z) is the initial value filter coefficient of the torque characteristic value of the previous sampling period; k TrqWeightVar is the update coefficient; r TrqWeightGain is the gain coefficient; r TrqWeightInc is the cumulative coefficient; b TrqDetectErr (z) is the flag bit for whether the engine combustion torque is abnormal in the previous sampling period. If it is abnormal, it is 1; if it is not abnormal, it is 0; The initial value of the torque characteristic value S TrqDetectRaw Filter and obtain the filtered torque characteristic value S TrqDetect : S TrqDetect =(1-r TrqWeightVarFilt )×S TrqDetect (z)+r TrqWeightVar ×S TrqDetectRaw 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; Determine the combustion torque abnormality judgment lower limit value M TrqBoundLower : Among them, k BunndLower is the lower limit deviation coefficient; Calculate the torque deviation M used to determine whether the engine combustion torque is abnormal ErrEst : M ErrEst =M TrqDetectDelta -M TrqBoundLower Determine whether the engine combustion torque is normal: 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; Determine the cylinder number of the abnormal cylinder shutdown: If b TrqDetectErr If it is set to 1, the cylinder number in the power stroke under the corresponding evaluation window is read, indicating that the corresponding cylinder has abnormal cylinder shutdown.

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 when the engine is abnormally deactivated and the combustion torque when the engine is not abnormally deactivated within the evaluation window meets the 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 of the abnormal engine cylinder deactivation is determined by 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, including: If the cylinder number detected by the first engine abnormal cylinder deactivation and torque reduction diagnostic method is the same as the cylinder number detected by the second engine abnormal cylinder deactivation and torque reduction diagnostic method, the corresponding cylinder is abnormally deactivated; and the corresponding cylinder abnormal cylinder deactivation fault judgment is no longer performed in the subsequent vehicle driving cycle until the diagnostic instrument clears the fault and then the abnormal cylinder deactivation fault judgment is performed again; If the first engine abnormal cylinder deactivation and torque reduction diagnostic method detects the cylinder number of abnormal cylinder deactivation, but the second 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 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 the subsequent vehicle driving cycle, the abnormal cylinder deactivation fault judgment of the corresponding cylinder is no longer performed until the diagnostic instrument clears the fault and then the abnormal cylinder deactivation fault judgment is performed again; If the first engine abnormal cylinder deactivation and torque reduction diagnostic method detects the cylinder number of abnormal cylinder deactivation, but the second 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 that occur does not exceed the preset number A, it is characterized that the combustion abnormality is in a pending state, and the threshold coefficient for determining abnormal cylinder deactivation of the fixed cylinder under the first engine abnormal cylinder deactivation and torque reduction diagnostic method is updated to the second multiple, and is updated at most once per driving cycle, and the corresponding cylinder abnormal cylinder deactivation fault determination 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 abnormal cylinder deactivation, 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 that occur exceeds the preset number A, it is characterized as abnormal cylinder deactivation, and the threshold coefficient for determining abnormal 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 of the corresponding cylinder is no longer performed in subsequent vehicle driving cycles until the diagnostic instrument clears the fault and then 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 abnormal cylinder deactivation, 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 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 Updated to a multiple of the second, and updated at most once per driving cycle, and abnormal cylinder deactivation fault judgment of the corresponding cylinder 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 both fail to detect the same cylinder number, abnormal cylinder deactivation fault judgment is still performed in the subsequent vehicle driving cycle; Among them, 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 engine abnormal cylinder deactivation and torque reduction diagnosis method according to any one of claims 1 to 13 is implemented.

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