Judgment method for oil injection action of oil way of fixed cylinder of engine

Abstract

The invention discloses an engine fixed cylinder oil way oil injection action judgment method which comprises the following steps: when enabling conditions of the engine fixed cylinder oil way oil injection action judgment method are met, obtaining operation time of each cylinder of an engine at a section of crankshaft operation angle, and calculating an average value of the operation time; determining a running time updating coefficient under the condition that the running time updating optimization processing activation condition is met; determining the final operation time according to the value of the update flag bit and the operation time update coefficient; according to the characteristic coefficient and the self-learning correction coefficient, the value of an initial flag bit and the value of an initial fuel cut-off flag bit of the fixed air cylinder are determined; and active fuel cut-off is carried out under the condition that the fuel cut-off enabling condition is met, the value of the fuel cut-off flag bit of each air cylinder of the engine is determined, and whether real fuel cut-off occurs in the air cylinders of the engine or not is judged. The method provided by the invention can detect whether fuel cut occurs in the fixed cylinder of the engine, so that a driver is reminded to maintain and detect the engine in time, and the engine is protected.

Description

Technical Field

[0001] The invention relates to the technical field of engine control, and in particular to a method for judging the oil injection action of an engine fixed cylinder oil circuit. Background Art

[0002] Engine combustion will generate torque, but one or more cylinders of the engine may have abnormal combustion problems continuously. If the problem of the fixed cylinder can be identified and located, it means that there is a problem with the ignition or injection of the cylinder, which may be caused by the relevant sensor or injection ignition actuator or wiring harness. Therefore, it is necessary to detect the oil cut-off of the fixed cylinder of the engine, so as to remind the driver to repair and detect in time to protect the engine. Summary of the invention

[0003] The technical problem to be solved by the present invention is to provide a method for judging the oil injection action of the fixed cylinder oil circuit of an engine in view of the deficiencies in the prior art. The method can detect whether the fixed cylinder of the engine is out of oil, thereby reminding the driver to repair and inspect the engine in time to protect the engine.

[0004] To achieve the above object, according to one aspect of the present invention, a method for determining the oil injection action of a fixed cylinder oil circuit of an engine is provided, comprising:

[0005] When the enabling conditions of the method for judging the oil injection action of the fixed cylinder oil circuit of the engine are met, the running time of each cylinder of the engine in a crankshaft operation angle is obtained, and the average running time of each cylinder of the engine in a number of consecutive sampling periods is calculated;

[0006] When the activation conditions for the run time update optimization process are met, a fuel cut-off is requested for all cylinders of the engine, when the engine is in the running process and the vehicle is in the coasting process; an evaluation area is divided according to the engine speed, and a run time update coefficient is determined according to the evaluation area;

[0007] Determine a value of a runtime update optimization counter and an initial value of a runtime update coefficient according to the runtime update coefficient and the runtime average value;

[0008] Determine the value of the update flag according to the value of the runtime update optimization counter; determine the updated runtime update coefficient according to the value of the update flag, the runtime update coefficient initial value and the runtime update coefficient;

[0009] Determine a final running time according to the value of the update flag, the updated running time update coefficient and the running time;

[0010] According to the final running time, the average final running time of each cylinder of the engine in a plurality of consecutive sampling cycles is obtained, and the maximum and minimum values ​​of the average final running time are obtained; the characteristic coefficient is calculated according to the average final running time and its maximum and minimum values; the value of the initial flag of the fixed cylinder is determined according to the characteristic coefficient and the self-learning correction coefficient;

[0011] Determine the value of the initial fuel cut-off flag of the fixed cylinder according to the value of the initial flag; wherein the value of the initial fuel cut-off flag is 0 or 1;

[0012] When the fuel cut-off enabling conditions are met, the engine cylinder whose initial fuel cut-off flag value is 1 is actively cut off from fuel, the final operating time average value of each engine cylinder in the fuel cut-off state within several consecutive sampling cycles is obtained, and the maximum and minimum values ​​of the final operating time average values ​​of each engine cylinder in the fuel cut-off state are determined; the value of the fuel cut-off flag of each engine cylinder is determined according to the final operating time average value of each engine cylinder in the fuel cut-off state and its maximum and minimum values ​​and the value of the initial fuel cut-off flag, and it is judged whether the engine cylinder whose initial fuel cut-off flag value is 1 is actually cut off from fuel.

[0013] In the above scheme, the enabling conditions of the method for judging the oil injection action of the fixed cylinder oil circuit of the engine include:

[0014] (1) Entering the fire diagnosis area specified in the regulations;

[0015] (2) No request for fuel cut-off;

[0016] (3) The gear position has not changed;

[0017] (4) The clutch is in full engagement;

[0018] (5) Non-uneven road surface;

[0019] (6) The water temperature is within the preset range;

[0020] (7) The throttle opening fluctuation is small during the diagnosis process;

[0021] (8) The engine is in operation.

[0022] In the above scheme, the gear position has not changed means that when the gear position changes, it takes a delay of more than the preset gear change time to activate the engine cylinder injection condition detection method; the clutch is in a fully engaged state means that after the clutch is engaged, it takes a delay of more than the preset clutch time to activate the engine cylinder injection condition detection method; the throttle opening fluctuation is small during the diagnosis process means that the throttle opening fluctuation is small during the diagnosis process means that the difference between the maximum opening and the minimum opening of the throttle within the preset throttle time is less than the preset throttle opening difference.

[0023] In the above scheme, the method for obtaining the running time of each cylinder of the engine in a crankshaft operation angle and calculating the average running time of each cylinder of the engine in a number of consecutive sampling periods is:

[0024] The crankshaft operation angle section 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, and the operation time of each cylinder of the engine in the crankshaft operation angle section is obtained; the operation time in a number of consecutive sampling periods is T n [0,1,2,3…], where n is the engine cylinder number; wherein the default first value of the running time is 0;

[0025] The average running time of the running time in several consecutive sampling periods is t RawSegmentAvg [0,1,2…], where t RawSegmentAvg [0] is the average running time of the first cylinder of the engine.

[0026] In the above solution, the runtime update optimization processing activation conditions include:

[0027] (1) The engine is in operation;

[0028] (2) All cylinders of the engine are in the fuel cut-off state;

[0029] (3) The engine does not directly participate in driving the vehicle;

[0030] (4) The engine does not experience knock or pre-ignition;

[0031] (5) The running time in several consecutive sampling periods is not 0;

[0032] (6) The engine did not malfunction.

[0033] In the above scheme, the method of dividing the evaluation area according to the engine speed and determining the running time update coefficient according to the evaluation area is:

[0034] The engine speed is divided into 10 evaluation areas as follows:

[0035]

[0036] Each cylinder of the engine has a corresponding running time update coefficient in each of the 10 evaluation areas; the running time update coefficients of the 10 evaluation areas are r n [0,1,2…,9], where n is the engine cylinder number, which can be saved after the vehicle is powered off, and its initial value is 1.

[0037] In the above scheme, the method for determining the value of the runtime update optimization counter and the initial value of the runtime update coefficient is:

[0038] If the activation condition of the runtime update optimization process is not satisfied and the evaluation area changes, at least one of the two conditions is satisfied, the runtime update optimization counter Cnt is set to AdaptCounter Reset to 1 and update the running time coefficient to the initial value r raw [0,1,2...] Reset to the running time update coefficient r stored at power-down n The specific value of the running time update coefficient of the current evaluation area in [0,1,2…,9]; where r raw [0] is the initial value of the engine first cylinder operation time update coefficient, r raw [1] is the initial value of the running time update coefficient of the second cylinder of the engine, and so on;

[0039] If the activation condition of the running time update optimization process is not satisfied and the evaluation area changes, the running time update optimization counter Cnt is incremented after each sampling period of the running time. AdaptCounter The value of which is incremented by 1, wherein the runtime updates the optimization counter Cnt AdaptCounter The default initial value is 0, and the initial value r of the running time update coefficient is accumulated. raw [0,1,2...] is used as the initial value of the new running time update coefficient. The accumulation method is as follows, taking the first cylinder of the engine as an example, and the other cylinders are similar:

[0040] The operating time update coefficient initial value of the first cylinder of the engine where r raw [0](z) is the initial value of the operating time update coefficient obtained in the previous sampling cycle, and Avg is the average value of the operating time average values ​​of all cylinders.

[0041] In the above scheme, the method for determining the value of the update flag bit and determining the updated running time update coefficient is as follows:

[0042] Determine whether the running time in the current evaluation area has completed the first update. If the first update is not completed, the running 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. If the running time in the current evaluation area is updated to optimize the counter Cnt AdaptCounter The value is not less than the preset value Cnt A1 The number of times Cnt AdaptWeightCounter Greater than the preset number Cnt B1When , it means that the running time has just completed the first update, and the update flag bit b FirstAdaptDone The value is 1; otherwise, update the flag bit b FirstAdaptDone The value of is 0; wherein the runtime update optimization counter Cnt AdaptCounter The value is not less than the preset value Cnt A1 The number of times Cnt AdaptWeightCounter The value of is obtained by updating the cumulative method, and the updating cumulative method is: the number of times Cnt AdaptWeightCounter The default value is 0, and the optimization counter Cnt is updated at runtime. AdaptCounter After reset, the running time is accumulated again, and the optimized counter Cnt is updated. AdaptCounter Not less than the preset value Cnt A1 After that, the number of times Cnt AdaptWeightCounter The value of is increased by 1, that is, each time the running time updates the optimization counter Cnt AdaptCounter After reset, the runtime updates the optimization counter Cnt AdaptCounter Update at most once; the number Cnt AdaptWeightCounter and the update flag bit b FirstAdaptDone The default value is 0, which will be saved after the vehicle is powered off;

[0043] In the update flag bit b FirstAdaptDone The value of is 0, and the runtime updates the optimization counter Cnt AdaptCounter The value is not less than the preset value Cnt A1 When the running time update coefficient r is allowed to be updated n [0,1,2…,9]; updating the running time update coefficient r n The method for [0,1,2…,9] is:

[0044] Taking the current evaluation area as 0 as an example, the methods for other evaluation areas are similar; update the running time update coefficient r when the current evaluation area is 0 n [0] = k AdaptWeight × raw [n]+(1-k AdaptWeight )×r n [0](z); where r raw [n] is the initial value r of the running time update coefficient raw The value of the n+1th cylinder in [0,1,2…]; where r n [0](z) is the specific value of the running time update coefficient when the evaluation area is 0 in the previous sampling period; where k AdaptWeight is the weighting coefficient; similarly, the updated running time update coefficients of other evaluation areas can be obtained, that is, the updated running time update coefficient r n[0,1,2…,9];

[0045] In the update flag bit b FirstAdaptDone When the value of is 1, and the runtime updates the optimization counter Cnt AdaptCounter The value is not less than the preset value Cnt A2 When the running time update coefficient r is allowed to be updated n [0,1,2…,9], where Cnt A2 Not less than Cnt A1 ; The update of the running time update coefficient r n The method for [0,1,2…,9] is:

[0046] Taking the current evaluation area as 0 as an example, the methods for other evaluation areas are similar; update the running time update coefficient r when the current evaluation area is 0 n [0] = k Adapt × raw [n]+(1-k Adapt )×r n [0](z); where r raw [n] is the initial value r of the running time update coefficient raw The value of the n+1th cylinder in [0,1,2…]; where r n [0](z) is the specific value of the running time update coefficient when the evaluation area is 0 in the previous sampling period; where k Adapt is the weighting coefficient, and k Adapt No more than k AdaptWeight Similarly, the updated running time update coefficients of other evaluation areas can be obtained, which are the updated running time update coefficients r n [0,1,2…,9].

[0047] In the above scheme, the method for determining the final running time is:

[0048] In the update flag bit b FirstAdaptDone When the value of is 0, the final running time T n-New is the running time;

[0049] In the update flag bit b FirstAdaptDone When the value is 1, the final running time T n-New It is the product of the running time and the specific value of the updated running time update coefficient in the current evaluation area.

[0050] In the above scheme, the method for obtaining the characteristic coefficient is: the average final running time of each cylinder of the engine in a number of consecutive sampling cycles is T n_Avg , find the maximum value of the final running time average value as Tmax , the minimum value is T min ; The characteristic coefficient r CynDetectRaw For several consecutive sampling periods (T max -T min ) / T min The self-learning correction coefficient k Adapt The default initial value is 0, which will be saved after the vehicle is powered off.

[0051] In the above scheme, the method for determining the value of the initial flag of the fixed cylinder according to the characteristic coefficient and the self-learning correction coefficient is: if r CynDetectRaw (1+k Adapt )≥r CynDetectOffLim , then the initial flag bit bCynOffRaw The value is 1, otherwise the initial flag bCynOffRaw The value of is 0; CynDetectOffLim is a threshold coefficient for determining the continuous fuel cutoff of a fixed cylinder. The threshold coefficient is obtained by bench calibration. The specific method is as follows: the threshold coefficient is determined by the average engine speed and the average engine intake density. On the engine bench, the self-learning correction coefficient k Adapt Under the premise of being 0, read the characteristic coefficient r under the active oil cut-off condition CynDetectRaw and the characteristic coefficient r without oil cut-off CynDetectRaw The minimum value of the average value of the characteristic coefficient under the active oil cut-off condition and the characteristic coefficient under the non-oil cut-off condition obtained by multiple samplings is taken as the threshold coefficient r for judging the continuous oil cut-off of the fixed cylinder. CynDetectOffLim ; wherein the average engine speed and the average engine intake density are respectively the average values ​​of the current sampling cycle and the four sampling cycles before it, a total of five sampling cycles; according to the test bench, multiple samplings are performed, and the fixed cylinder continuous oil cut-off is actively set at different engine speeds and different engine intake densities, and the minimum value of the threshold coefficient obtained in multiple samplings is used as the threshold coefficient.

[0052] In the above scheme, the method for determining the value of the flag bit of the fixed cylinder according to the value of the initial flag bit is:

[0053] In the initial flag bCynOffRaw The value of is 1, if:

[0054] The first case: there is a final running time average value T of the engine cylinder in several consecutive sampling cycles n_Avg With T max equal; and determine its cylinder number;

[0055] Second case: Under the conditions of the first case, there is a preset value X>(T max-T n_Avg ) / T max >0, determine the cylinder number; the preset value X will be saved after the vehicle is powered off and will be continuously updated, and its default value is 0.08;

[0056] The third case: the final running time (T n -T max ) / T max All are within the preset range ±Y; Y will be saved after the vehicle is powered off and continuously updated, and its default value is 0.08;

[0057] The fourth case: at least one cylinder does not meet the first case or the second case;

[0058] Fifth case: The cylinder numbers that meet the first or second case are recorded according to the cylinder working order. If the number of cylinders that do not meet the first or second case between two consecutive cylinder numbers that meet the first or second case is not less than 2, then T n_Avg With T min The equal cylinder number is not the next working cylinder number that satisfies the first condition or the second condition;

[0059] If multiple sampling times Cnt CynoffDelay When the first, second, third, fourth, and fifth conditions are met under the above conditions, the initial fuel cut-off flag position b of the cylinder that meets the first or second condition is CynOff The value is 1, the initial fuel cut-off flag of other cylinders is b CynOff The value of is 0;

[0060] The multiple sampling times Cnt CynoffDelay The initial default value is 8, 3≤Cnt CynoffDelay ≤15, and it will be saved after the vehicle is powered off.

[0061] In the above scheme, the fuel cut-off enabling conditions include:

[0062] (1) satisfying the engine fuel injection performance detection enabling conditions;

[0063] (2) The vehicle speed exceeds the preset value;

[0064] (3) The engine does not experience knock and pre-ignition;

[0065] (4) The exhaust temperature does not exceed the preset protection temperature;

[0066] (5) The gasoline particulate filter does not request automatic regeneration;

[0067] (6) The oxygen storage capacity of the catalyst does not exceed the preset coefficient of its total oxygen storage capacity;

[0068] (7) No failure of components related to the fuel injection system occurs;

[0069] (8) The difference between the average engine speed and the average engine speed obtained during the bench calibration process of the threshold coefficient is within a preset range;

[0070] (9) The difference between the average engine intake density and the average intake density obtained during the bench calibration process of the threshold coefficient is within a preset range.

[0071] In the above scheme, the method for judging whether the engine cylinder whose initial fuel cut-off flag has a value of 1 has actually been cut off from fuel is:

[0072] Actively cut off fuel for the cylinders that meet the first condition or the second condition, and re-obtain the final average running time T of each cylinder of the engine in the fuel cut-off state. n_AvgNew and the maximum value T of the average final running time of each cylinder of the engine in the fuel cut-off state maxNew With the minimum value T minNew ;

[0073] (1) For the initial fuel cut-off flag b CynOff The value of the cylinder is 1, if and When the oil cut-off mark of this cylinder is b CynOffFuelCut =b CynOff =1, the multiple sampling times Cnt CynoffDelay Subtract 1 and save after power off, the self-learning correction coefficient k Adapt Remain unchanged; C1 is the preset value;

[0074] (2) For the initial fuel cut-off flag b CynOff For a cylinder with a value of 1, if and If only one of the following is satisfied, the oil cut-off flag of this cylinder is b CynOffFuelCut =0, the number of multiple sampling times Cnt CynoffDelay Remain unchanged; the self-learning correction coefficient And save it after power off;

[0075] (3) For the initial fuel cut-off flag b CynOff The value of the cylinder is 1, if and If both are not satisfied, the oil cut-off mark of this cylinder is b CynOffFuelCut =0, the multiple sampling times Cnt CynoffDelay Add 2, the self-learning correction coefficient And save it after power off;

[0076] (4) For the initial fuel cut-off flag b CynOff The value of cylinder A is 0. If the final running time average value of cylinder A is T A_Avg satisfy The oil cut-off mark of this cylinder is b CynOffFuelCut =0, the number of multiple sampling times Cnt CynoffDelay Remain unchanged, the self-learning correction coefficient And save after power off; C2 is the preset value;

[0077] (5) In other cases, the cylinder oil cut-off mark is b CynOffFuelCut =0, the number of multiple sampling times Cnt CynoffDelay and the self-learning correction coefficient k Adapt remain unchanged;

[0078] If the value of the initial fuel cut-off flag is 1, the fuel cut-off flag b of the engine cylinder CynOffFuelCut =1, it means that the engine cylinder has a real oil cut-off.

[0079] In the above solution, the updating method of X in the preset value X and Y in the preset range ±Y is:

[0080] At the oil cut-off mark position b of the corresponding cylinder CynOffFuelCut =1, X=X(z)+0.02, Y=Y(z)+0.01; wherein X(z) and Y(z) are X in the preset value X and Y in the preset range ±Y after the last update; the preset values ​​X and X and Y in the preset range ±Y of other cylinders are not updated;

[0081] At the oil cut-off mark position b of the corresponding cylinder CynOffFuelCut = 0, the oil cut-off flag b of the corresponding cylinder will be accumulated. CynOffFuelCut The number of times CNT is 0 is increased by 1 each time, and the default value of CNT is 0; if the number of times CNT is not less than the preset value Z, then: X = X(z)-0.007, Y = Y(z)-0.005, after the update is completed, the number of times CNT is cleared to 0 until the next time the oil cut flag b of the same cylinder is determined again CynOffFuelCut Is it 0? If the fuel cut flag bit b CynOffFuelCut If it is 0, the number CNT of the corresponding cylinder is increased by 1 again; in other cases: X=X(z), Y=Y(z); wherein X(z), Y(z) are X in the preset value X after the last update and Y in the preset range ±Y.

[0082] The reason why the speed of X and Y learning increase is faster than the speed of learning decrease is that the increase of X and Y learning occurs when the fixed cylinder has continuous oil cut-off, while the learning decrease occurs when the fixed cylinder has not had continuous oil cut-off. When the fixed cylinder has been continuously cut off, the reason for increasing X and Y is that the purpose is to actively check the oil cut-off during the oil cut-off process. In the subsequent judgment process, increasing the threshold for judging continuous oil cut-off can speed up the entry into the judgment of continuous oil cut-off, thereby speeding up the recognition; while the learning decrease occurs when the fixed cylinder has not been cut off. Because it is an active check, there is still no continuous oil cut-off. It is necessary to slowly reduce the oil cut-off judgment threshold, and the situation of continuous oil cut-off in the cylinder is smaller. However, in order to avoid not identifying the continuous oil cut-off in time, the speed of X and Y decreasing is slower.

[0083] The present invention provides a method for judging the injection action of an engine fixed cylinder oil circuit. The method can check whether any fixed cylinder has an oil cut-off. If an oil cut-off occurs, the corresponding cylinder is forced to cut off the oil, and it is judged whether the situation is consistent with the previous situation. If the situation is consistent, it is confirmed that the combustion abnormality is caused by the oil cut-off, so that the driver can be reminded to perform maintenance and inspection in time to protect the engine. BRIEF DESCRIPTION OF THE DRAWINGS

[0084] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present invention. Also, throughout the accompanying drawings, the same reference figures are used to represent the same components. In the drawings:

[0085] Figure 1 The present invention is a flowchart of a method for determining the oil injection action of a fixed cylinder oil circuit of an engine according to an embodiment of the present invention. DETAILED DESCRIPTION

[0086] 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.

[0087] It should be understood that the size of the serial numbers of the steps in the 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.

[0088] Example 1

[0089] The present application provides a method for detecting the fuel injection condition of an engine cylinder. Figure 1 ,include:

[0090] S1, when the enabling conditions of the engine fixed cylinder oil circuit injection action judgment method are met, the running time of each cylinder of the engine in a crankshaft operation angle is obtained, and the average running time of each cylinder of the engine in several consecutive sampling periods is calculated.

[0091] Specifically, in this embodiment, in order to ensure the accuracy and safety of the judgment of the oil injection action of the fixed cylinder oil circuit of the engine, the method for judging the oil injection action of the fixed cylinder oil circuit of the engine of the present invention needs to be performed under the enabling condition to reduce the error of the detection method. In the present invention, the enabling condition judgment sampling period is 10ms, and the enabling conditions of the method for judging the oil injection action of the fixed cylinder oil circuit of the engine include:

[0092] (1) Entering the fire diagnosis area specified in the regulations;

[0093] (2) No request for fuel cut-off;

[0094] (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 continuous fuel cut-off verification method;

[0095] (4) The clutch is in full engagement and the engine continuous fuel cut-off verification method can only be activated after a delay of 1 second after the clutch is engaged;

[0096] (5) Non-uneven road surface;

[0097] (6) Water temperature is higher than -6°C;

[0098] (7) The throttle opening fluctuation is small during the diagnosis process, and the difference between the maximum and minimum throttle openings within 0.1 s is less than 15%;

[0099] (8) The engine is in operation.

[0100] After the above conditions are met, the engine fixed cylinder oil circuit injection action judgment can be performed. When the above conditions are not met, the vehicle's working conditions will cause misjudgment. If the enabling conditions are not met during the diagnosis process, the diagnosis is terminated and the engine fixed cylinder oil circuit injection action judgment is performed again after the next diagnosis condition is met.

[0101] Specifically, in this embodiment, the method for obtaining the running time of each cylinder of the engine in a crankshaft running angle is: a crankshaft running angle is a crankshaft angle of each cylinder of the engine from 80° after the compression top dead center of each cylinder to 260° after the compression top dead center of its corresponding cylinder, and the running time of each cylinder of the engine in this crankshaft running angle is obtained, and the running time in 10 consecutive sampling periods is T n [0, 1, 2, 3…9], where n is the cylinder number; the default initial value of the running time is 0; the running time T nThe value of [0, 1, 2, 3…9] will be continuously updated; n [0] represents the running time of each cylinder of the engine at the current sampling time, T n [1] represents the running time of each cylinder of the engine in the last sampling, and so on. In particular, all sampling in the subsequent steps is that the crankshaft of each cylinder rotates from 80° after the compression top dead center to 260° after the compression top dead center, that is, the crankshaft rotates 180°.

[0102] In this embodiment, the number of engine cylinders is 4, and the average running time of each cylinder of the engine in 10 consecutive sampling cycles is calculated. RawSegmentAvg [0,1,2,3], where t RawSegmentAvg [0] is the average running time of the first cylinder of the engine, t RawSegmentAvg [1] is the average operating time of the second cylinder of the engine, and so on.

[0103] S2, when the activation conditions for the running time update optimization processing are met, a fuel cut-off is requested for all cylinders of the engine. At this time, the engine is in the running process and the vehicle is in the coasting process; the evaluation area is divided according to the engine speed, and the running time update coefficient is determined according to the evaluation area.

[0104] Specifically, in this embodiment, the runtime update optimization process activation conditions include:

[0105] (1) The engine is in operation;

[0106] (2) All cylinders of the engine are in the fuel cut-off state;

[0107] (3) The engine is not directly involved in driving the vehicle, that is, the engine is not connected to the transmission system;

[0108] (4) The engine does not experience knock or pre-ignition;

[0109] (5) The running time in 10 consecutive sampling periods is not 0;

[0110] (6) The engine did not malfunction.

[0111] Specifically, in this embodiment, the evaluation area is divided according to the engine speed, and the method for determining the running time update coefficient according to the evaluation area is:

[0112] The engine speed is divided into 10 evaluation areas as follows:

[0113]

[0114] Each cylinder of the engine has a specific value of the running time update coefficient in each of the 10 evaluation areas. The running time update coefficients of the 10 evaluation areas are r n [0,1,2…,9], where n is the engine cylinder number, which can be saved after the vehicle is powered off, and its initial value is 1. Specifically, if the engine speed is 750 rpm or less, the current evaluation area is 0, if the engine speed is greater than 750 rpm and less than 1000 rpm, the current evaluation area is 1, and so on.

[0115] S3, determining the value of the runtime update optimization counter and the initial value of the runtime update coefficient according to the runtime update coefficient and the runtime average value.

[0116] Specifically, in this embodiment, if the activation condition of the runtime update optimization process is not satisfied and the evaluation area changes, at least one of the two conditions is satisfied, the runtime update optimization counter Cnt is set to AdaptCounter Reset to 1 and update the running time coefficient to the initial value r raw [0,1,2,3] Reset to the running time update coefficient r stored at power-off n The specific value of the running time update coefficient of the current evaluation area in [0,1,2…,9]; where r raw [0] is the initial value of the engine first cylinder operation time update coefficient, r raw [1] is the initial value of the operating time update coefficient of the second cylinder of the engine, and so on.

[0117] If the activation condition of the running time update optimization processing is not met and the evaluation area changes, the running time update optimization counter Cnt is set after each sampling period of the running time. AdaptCounter The value of is increased by 1, where the runtime updates the optimization counter Cnt AdaptCounter The default initial value is 0, and the cumulative running time update coefficient initial value r raw [0,1,2,3] is used as the initial value of the new running time update coefficient. The accumulation method is as follows. Taking the first cylinder of the engine as an example, the other cylinders are similar:

[0118] Initial value of the engine's first cylinder operation time update coefficient where r raw [0](z) is the initial value of the running time update coefficient obtained in the previous sampling period, t R aw S egment A vg[0] is the average running time of the first cylinder of the engine, and Avg is the average running time of all cylinders, that is,

[0119] S4, determining the value of the update flag according to the value of the runtime update optimization counter; determining the updated runtime update coefficient according to the value of the update flag, the initial value of the runtime update coefficient and the runtime update coefficient.

[0120] Specifically, in this embodiment, if the running time in the current evaluation area updates the optimization counter Cnt AdaptCounter The value is not less than the preset value Cnt A1 The number of times Cnt AdaptWeightCounter Greater than the preset number Cnt B1 When , it means that the running time has just completed the first update, and the update flag bit b FirstAdaptDone The value is 1; otherwise, update the flag bit b FirstAdaptDone The value of is 0; in this embodiment, the preset value Cnt A1 The preset number is 5, Cnt B1 is 3.

[0121] Among them, the running time update optimization counter Cnt AdaptCounter The value is not less than the preset value Cnt A1 The number of times Cnt AdaptWeightCounter The value is obtained by updating the cumulative method, and the updating cumulative method is: times Cnt AdaptWeightCounter The default value is 0, and the optimization counter Cnt is updated at runtime. AdaptCounter After reset, the running time is accumulated again and the optimization counter Cnt is updated. AdaptCounter Not less than the preset value Cnt A1 After that, the number of times Cnt AdaptWeightCounter The value of is increased by 1, that is, the optimization counter Cnt is updated every time the running time is AdaptCounter After reset, the running time updates the optimization counter Cnt AdaptCounter Update at most once; the number of times is Cnt AdaptWeightCounter and update flag b FirstAdaptDone The default value is 0, and it will be saved after the vehicle is powered off.

[0122] In the update flag b FirstAdaptDone The value is 0, and the runtime update optimization counter Cnt AdaptCounter The value is not less than the preset value Cnt A1 Only when the running time update coefficient r is allowed to be updated n [0,1,2…,9]; Update the running time update coefficient r n The method for [0,1,2…,9] is:

[0123] Taking the current evaluation area as 0 as an example, the methods for other evaluation areas are similar; update the running time update coefficient r when the current evaluation area is 0 n [0] = kAdaptWeight × raw [n]+(1-k AdaptWeight )×r n [0](z); where r raw [n] is the initial value of the running time update coefficient r raw The value of the n+1th cylinder in [0,1,2,3]; where r n [0](z) is the specific value of the running time update coefficient when the evaluation area is 0 in the previous sampling period (i.e., the running time update coefficient r n When the evaluation area is 0 in [0,1,2,...,9], r n [0]); where k AdaptWeight is the weighting coefficient, which is 0.15 in this example; similarly, the updated running time update coefficients of other evaluation areas can be obtained, which is the updated running time update coefficient r n [0,1,2…,9].

[0124] In the update flag b FirstAdaptDone When the value is 1, and the runtime updates the optimization counter Cnt AdaptCounter The value is not less than the preset value Cnt A2 Only when the running time update coefficient r is allowed to be updated n [0,1,2…,9], where Cnt A2 Not less than Cnt A1 In this embodiment, Cnt A2 =16.

[0125] Update the running time update coefficient r n The method for [0,1,2…,9] is:

[0126] Taking the current evaluation area as 0 as an example, the methods for other evaluation areas are similar; update the running time update coefficient r when the current evaluation area is 0 n [0] = k Adapt × raw [n]+(1-k Adapt )×r n [0](z); where r raw [n] is the initial value of the running time update coefficient r raw The value of the n+1th cylinder in [0,1,2,3]; where r n [0](z) is the specific value of the running time update coefficient when the evaluation area is 0 in the previous sampling period (i.e., the running time update coefficient r n When the evaluation area is 0 in [0,1,2,...,9], r n [0]); where k Adapt is the weighting coefficient, which is 0.005 in this example, and kAdapt No more than k AdaptWeight Similarly, the updated running time update coefficients of other evaluation areas can be obtained, which is the updated running time update coefficient r n [0,1,2…,9].

[0127] S5, determining the final running time according to the value of the update flag, the updated running time update coefficient and the running time.

[0128] Specifically, in this embodiment, the method for determining the final running time is:

[0129] In the update flag b FirstAdaptDone When the value is 0, the final running time T n-New is the running time T n [0,1,2,3…];

[0130] In the update flag b FirstAdaptDone When the value is 1, the final running time is T n-New is the running time T n [0,1,2,3…] multiplied by the updated runtime update coefficient in the current evaluation area.

[0131] S6, according to the final running time, calculate the average value of the final running time of each cylinder of the engine in several consecutive sampling cycles to calculate the characteristic coefficient; according to the characteristic coefficient and the self-learning correction coefficient, determine the value of the initial flag of the fixed cylinder.

[0132] Specifically, in this embodiment, the final running time average value of each cylinder of the engine in 5 consecutive sampling cycles is calculated, and each cylinder is calculated separately to obtain the final running time average value T of each cylinder. n_Avg :

[0133]

[0134] Among them, the maximum value of the average final running time of each cylinder of the engine is T max , the minimum value is T min : In this example, if the engine is a 4-cylinder engine, then:

[0135] T Max =max(T 1_Avg , T 2_Avg , T 3_Avg , T 4_Avg );

[0136] T Min =min(T 1_Avg , T 2_Avg , T 3_Avg , T 4_Avg ).

[0137] In this embodiment, the characteristic coefficient r CynDetectRaw is the current sampling period The average value of the 5 sampling cycles before the 4 sampling cycles. Self-learning correction coefficient k Adapt The default initial value is 0, which will be saved after the vehicle is powered off. CynDetectOffLim The threshold coefficient is used to determine the continuous oil cut-off of the fixed cylinder. The threshold coefficient is calibrated on the test bench. The specific method is as follows: the threshold coefficient is determined by the average engine speed and the average engine intake density. On the engine test bench, the self-learning correction coefficient k Adapt Under the premise of being 0, read the characteristic coefficient r under active oil cut-off CynDetectRaw and the characteristic coefficient r without oil cut-off CynDetectRaw The minimum value of the average value of the characteristic coefficients under active oil cut-off and the characteristic coefficients under non-oil cut-off of multiple samplings is taken as the threshold coefficient r for judging the continuous oil cut-off of the fixed cylinder. CynDetectOffLim ; The average engine speed and average engine intake density are the average values ​​of the current sampling cycle and the previous four sampling cycles, a total of five sampling cycles. According to the test bench, multiple samplings are performed, and the fixed cylinder continuous oil cut-off is actively set at different engine speeds and different engine intake densities, and the minimum value of the threshold coefficient obtained in multiple samplings is used as the threshold coefficient.

[0138] According to the characteristic coefficient r CynDetectRaw and self-learning correction factor k Adapt The method for determining the value of the initial flag of the fixed cylinder is: if r CynDetectRaw (1+k Adapt )≥r CynDetectOffLim , then the initial flag bCynOffRaw The value is 1, otherwise the initial flag bCynOffRaw The value of is 0.

[0139] S7, determining the value of the flag bit of the fixed cylinder according to the value of the initial flag bit; wherein the value of the flag bit is 0 or 1.

[0140] Specifically, in this embodiment, the method for determining the value of the flag bit of the fixed cylinder according to the value of the initial flag bit is: bCynOffRaw The value of is 1, if:

[0141] The first case: There is a final running time average value T of the engine cylinder in 5 consecutive sampling cycles n_Avg With T max equal; and determine its cylinder number;

[0142] Second case: Under the conditions of the first case, there is a preset value X>(Tmax -T n_Avg ) / T max >0, determine the cylinder number; the preset value X will be saved after the vehicle is powered off and will be continuously updated, and its default value is 0.08;

[0143] The third case: the final running time (T n -T max ) / T max All are within the preset range ±Y; Y will be saved after the vehicle is powered off and continuously updated, and its default value is 0.08;

[0144] The fourth case: at least one cylinder does not meet the first case or the second case;

[0145] Fifth case: The cylinder numbers that meet the first or second case are recorded according to the cylinder working order. If the number of cylinders that do not meet the first or second case between two consecutive cylinder numbers that meet the first or second case is not less than 2, then T n_Avg With T min The cylinder number that is equal is not the next working cylinder number that satisfies the first or second situation. For example, in this example, the engine is a 4-cylinder engine, and the cylinder working sequence is 1-3-4-2-1-3-4-2-…. The cylinder numbers that meet the first or second situation 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 .

[0146] If multiple sampling times Cnt CynoffDelay When the first, second, third, fourth, and fifth conditions are met under the above conditions, the initial fuel cut-off flag position b of the cylinder that meets the first or second condition is CynOff The value of 1 indicates that the cylinder that meets the first or second condition may be continuously cut off from fuel. The initial cut-off flag of other cylinders is b CynOff The value is 0. Multiple sampling times Cnt CynoffDelay The initial default value is 8, 3≤Cnt CynoffDelay ≤15, and will be saved after the vehicle is powered off.

[0147] S8, when the fuel cut-off enabling conditions are met, the engine cylinder whose initial fuel cut-off flag value is 1 is actively cut off from fuel, the final operating time average value of each engine cylinder in the fuel cut-off state within several consecutive sampling cycles is obtained, and the maximum and minimum values ​​of the final operating time average values ​​of each engine cylinder in the fuel cut-off state are determined; the value of the fuel cut-off flag of each engine cylinder is determined according to the final operating time average value of each engine cylinder in the fuel cut-off state and its maximum and minimum values ​​and the value of the initial fuel cut-off flag, and it is judged whether the engine cylinder whose initial fuel cut-off flag value is 1 is actually cut off from fuel.

[0148] Specifically, in the embodiment of the present application, the fuel cut-off enabling conditions include:

[0149] (1) Satisfy the engine fuel injection performance detection enabling conditions;

[0150] (2) The speed exceeds 25 km / h;

[0151] (3) The engine does not experience knock and pre-ignition;

[0152] (4) The exhaust temperature does not exceed the preset protection temperature of 950°C;

[0153] (5) The gasoline particulate filter does not request automatic regeneration;

[0154] (6) The oxygen storage capacity of the catalyst does not exceed 90% of the total oxygen storage capacity;

[0155] (7) No failure of components related to the fuel injection system occurs;

[0156] (8) The difference between the average engine speed and the average engine speed obtained during the bench calibration process with the threshold coefficient is within a preset range; in this example, the preset range is ±20 rpm, where the average engine speed is the average of the current sampling period and the four sampling periods before it, a total of five sampling periods.

[0157] (9) The difference between the average engine intake air density and the average intake air density obtained during the bench calibration process with the threshold coefficient is within a preset range; in this example, the preset range is ±15 mgpl, where the average engine intake air density is the average of the current sampling period and the four sampling periods before it, a total of five sampling periods.

[0158] The method for judging whether the engine cylinder whose initial fuel cut-off flag value is 1 has actually been cut off from fuel is as follows:

[0159] Cut off the fuel supply to the cylinders that meet the first or second conditions, and re-obtain the final average running time T of each cylinder of the engine. n_AvgNew and the maximum value T of the average final running time of each cylinder of the engine maxNew With the minimum value T minNew;

[0160] (1) For the initial fuel cut-off flag b CynOff The value of the cylinder is 1, if and When the oil cut-off mark of this cylinder is b CynOffFuelCut =b CynOff =1, multiple sampling times Cnt CynoffDelay Subtract 1 and save after power off, self-learning correction coefficient k Adapt Maintain unchanged; C1 is the preset value, in this example C1 is 0.08;

[0161] (2) For the initial fuel cut-off flag b CynOff The value of the cylinder is 1, if and If only one of the following is satisfied, the oil cut-off flag of this cylinder is b CynOffFuelCut =0, multiple sampling times Cnt CynoffDelay Remain unchanged; self-learning correction coefficient And save it after power off;

[0162] (3) For the initial fuel cut-off flag b CynOff The value of the cylinder is 1, if and If both are not satisfied, the oil cut-off mark of this cylinder is b CynOffFuelCut = 0, multiple sampling times Cnt CynoffDelay Add 2, self-learning correction coefficient And save it after power off;

[0163] (4) For the initial fuel cut-off flag b CynOff The value of cylinder A is 0. If the final running time average value of cylinder A is T A_Avg satisfy The oil cut-off mark of this cylinder is b CynOffFuelCut =0, multiple sampling times Cnt CynoffDelay Maintain unchanged, self-learning correction coefficient And save it after power off; C2 is the preset value, in this example, C2 is 0.2;

[0164] (5) In other cases, the cylinder oil cut-off mark is b CynOffFuelCut =0, multiple sampling times Cnt CynoffDelay and self-learning correction factor k Adapt remain unchanged;

[0165] If the fuel cut-off flag corresponding to the engine cylinder is b CynOffFuelCut =1, it means that the engine cylinder has a real oil cut-off.

[0166] In the above scheme, the updating method of X in the preset value X and Y in the preset range ±Y is:

[0167] At the oil cut-off mark position b of the corresponding cylinder CynOffFuelCut =1, X=X(z)+0.02, Y=Y(z)+0.01; X(z) and Y(z) are X in the preset value X and Y in the preset range ±Y after the last update; the preset value X and X and Y in the preset range ±Y of other cylinders are not updated;

[0168] At the oil cut-off mark position b of the corresponding cylinder CynOffFuelCut = 0, the oil cut-off flag b of the corresponding cylinder will be accumulated. CynOffFuelCut The number of times CNT is 0 is increased by 1 each time, and the default value of CNT is 0; if the number of times CNT is not less than the preset value Z (the preset value Z in this embodiment is 8), then: X = X(z)-0.007, Y = Y(z)-0.005, and the number CNT is cleared to 0 after the update is completed until the next time the oil cut flag b of the same cylinder is determined again CynOffFuelCut Is it 0? If the fuel cut flag bit b CynOffFuelCut If it is 0, the number CNT of the corresponding cylinder is increased by 1 again; in other cases: X=X(z), Y=Y(z); wherein X(z), Y(z) are X in the preset value X and Y in the preset range ±Y after the last update.

[0169] In summary, the method for judging the oil injection action of the fixed cylinder oil circuit of the engine provided by the present invention can detect whether the fixed cylinder of the engine is out of oil, thereby reminding the driver to repair and inspect the engine in time to protect the engine.

[0170] It should be pointed out that, according to the needs of implementation, the various steps described in this application can be divided into more steps, or two or more steps or partial operations of the steps can be combined into a new step to achieve the purpose of the present invention.

[0171] It will be easily understood by those skilled in the art that the above description is only a preferred embodiment of the present invention and is 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 judging the oil injection action of an engine fixed cylinder oil circuit, characterized in that: include: When the enabling conditions of the method for judging the oil injection action of the fixed cylinder oil circuit of the engine are met, the running time of each cylinder of the engine in a crankshaft operation angle is obtained, and the average running time of each cylinder of the engine in a number of consecutive sampling periods is calculated; When the activation conditions for the run time update optimization process are met, requesting fuel cut-off for all cylinders of the engine, dividing the evaluation area according to the engine speed, and determining the run time update coefficient according to the evaluation area; Determine a value of a runtime update optimization counter and an initial value of a runtime update coefficient according to the runtime update coefficient and the runtime average value; Determine the value of the update flag bit according to the value of the runtime update optimization counter; Determine an updated runtime update coefficient according to the value of the update flag, the initial value of the runtime update coefficient, and the runtime update coefficient; Determine a final running time according to the value of the update flag, the updated running time update coefficient and the running time; According to the final running time, an average value of the final running time of each cylinder of the engine in a plurality of consecutive sampling periods is calculated to calculate a characteristic coefficient; Determine the value of the initial flag of the fixed cylinder according to the characteristic coefficient and the self-learning correction coefficient; Determine the value of the initial fuel cut-off flag of the fixed cylinder according to the value of the initial flag; wherein the value of the initial fuel cut-off flag is 0 or 1; When the fuel cut-off enabling condition is met, the engine cylinder whose initial fuel cut-off flag value is 1 is actively cut off from fuel, the average final running time of each cylinder of the engine in a number of consecutive sampling cycles in the fuel cut-off state is obtained, and the maximum and minimum values ​​of the average final running time of each cylinder of the engine in the fuel cut-off state are determined; The value of the fuel cut-off flag of each cylinder of the engine is determined based on the average final running time of each cylinder of the engine in the fuel cut-off state, its maximum and minimum values, and the value of the initial fuel cut-off flag, and it is judged whether the engine cylinder whose initial fuel cut-off flag value is 1 has actually been cut off from fuel.

2. A method for judging the oil injection action of an engine fixed cylinder oil circuit according to claim 1, characterized in that: The method for obtaining the running time of each cylinder of the engine in a crankshaft operation angle and calculating the average running time of each cylinder of the engine in a number of consecutive sampling periods is: The crankshaft operation angle section 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. The operation time of each cylinder of the engine in the crankshaft operation angle section is obtained. The operation time in a number of consecutive sampling periods is T n [0,1,2,3…], where n is the engine cylinder number; The default initial value of the running time is 0; The average running time of the running time in several consecutive sampling periods is t RawSegmentAvg [0,1,2…], where t RawSegmentAvg [0] is the average running time of the first cylinder of the engine.

3. A method for judging the oil injection action of a fixed cylinder oil circuit of an engine according to claim 2, characterized in that: The evaluation area is divided according to the engine speed, and the method for determining the running time update coefficient according to the evaluation area is: The method of dividing the engine speed into the following 10 evaluation areas is: when the engine speed values ​​are 750rpm, 1000rpm, 1500rpm, 2000rpm, 2500rpm, 3000rpm, 3500rpm, 4000rpm, 4500rpm, and 5000rpm, the evaluation areas are 0, 1, 2, 3, 4, 5, 6, 7, 8, and 9 respectively; Each cylinder of the engine has a corresponding running time update coefficient in each of the 10 evaluation areas; the running time update coefficients of the 10 evaluation areas are r n [0,1,2…,9], where n is the engine cylinder number, which can be saved after the vehicle is powered off, and its initial value is 1.

4. A method for judging the oil injection action of a fixed cylinder oil circuit of an engine according to claim 3, characterized in that: The method for determining the value of the runtime update optimization counter and the initial value of the runtime update coefficient is: If the activation condition of the runtime update optimization process is not satisfied and the evaluation area changes, at least one of the two conditions is satisfied, the runtime update optimization counter Cnt is set to AdaptCounter Reset to 1 and update the running time coefficient to the initial value r raw [0,1,2...] Reset to the running time update coefficient r stored at power-down n The specific value of the running time update coefficient of the current evaluation area in [0,1,2…,9]; where r raw [0] is the initial value of the engine first cylinder operation time update coefficient, r raw [1] is the initial value of the running time update coefficient of the second cylinder of the engine, and so on; If the activation condition of the running time update optimization process is not satisfied and the evaluation area changes, the running time update optimization counter Cnt is incremented after each sampling period of the running time. AdaptCounter The value of is increased by 1, where the runtime updates the optimization counter Cnt AdaptCounter The default initial value is 0, and the initial value r of the running time update coefficient is accumulated. raw [0,1,2...] is used as the initial value of the new running time update coefficient. The accumulation method is as follows, taking the first cylinder of the engine as an example, and the other cylinders are similar: The operating time update coefficient initial value of the first cylinder of the engine where r raw [0](z) is the initial value of the operating time update coefficient obtained in the previous sampling cycle, and Avg is the average value of the operating time average values ​​of all cylinders.

5. The method for judging the oil injection action of the fixed cylinder oil circuit of an engine according to claim 4, characterized in that: The method for determining the value of the update flag and the update coefficient of the updated running time is as follows: If the running time in the current evaluation area updates the optimization counter Cnt AdaptCounter The value is not less than the preset value Cnt A1 The number of times Cnt AdaptWeightCounter Greater than the preset number Cnt B1 When , it means that the running time has just completed the first update, and the update flag bit b FirstAdaptDone The value of is 1; Otherwise, update flag b FirstAdaptDone The value of is 0; wherein the runtime update optimization counter Cnt AdaptCounter The value is not less than the preset value Cnt A1 The number of times Cnt AdaptWeightCounter The value of is obtained by updating the cumulative method, and the updating cumulative method is: the number of times Cnt AdaptWeightCounter The default value is 0, and the optimization counter Cnt is updated at runtime. AdaptCounter After reset, the running time is accumulated again, and the optimized counter Cnt is updated. AdaptCounter Not less than the preset value Cnt A1 After that, the number of times Cnt AdaptWeightCounter The value of is increased by 1, that is, each time the running time updates the optimization counter Cnt AdaptCounter After reset, the runtime updates the optimization counter Cnt AdaptCounter Update at most once; the number Cnt AdaptWeightCounter and the update flag bit b FirstAdaptDone The default value is 0, which will be saved after the vehicle is powered off; In the update flag bit b FirstAdaptDone The value of is 0, and the runtime updates the optimization counter Cnt AdaptCounter The value is not less than the preset value Cnt A1 When the running time update coefficient r is allowed to be updated n [0,1,2…,9]; updating the running time update coefficient r n The method for [0,1,2…,9] is: Taking the current evaluation area as 0 as an example, the methods for other evaluation areas are similar; update the running time update coefficient r when the current evaluation area is 0 n [0] = k AdaptWeight × raw [n]+(1-k AdaptWeight )×r n [0](z); where r raw [n] is the initial value r of the running time update coefficient raw The value of the n+1th cylinder in [0,1,2…]; where r n [0](z) is the specific value of the running time update coefficient when the evaluation area is 0 in the previous sampling period; where k AdaptWeight is the weighting coefficient; similarly, the updated running time update coefficients of other evaluation areas can be obtained, that is, the updated running time update coefficient r n [0,1,2…,9]; In the update flag bit b FirstAdaptDone When the value of is 1, and the runtime updates the optimization counter Cnt AdaptCounter The value is not less than the preset value Cnt A2 When the running time update coefficient r is allowed to be updated n [0,1,2…,9], where Cnt A2 Not less than Cnt A1 ; The update of the running time update coefficient r n The method for [0,1,2…,9] is: Taking the current evaluation area as 0 as an example, the methods for other evaluation areas are similar; update the running time update coefficient r when the current evaluation area is 0 n [0] = k Adapt × raw [n]+(1-k Adapt )×r n [0](z); where r raw [n] is the initial value r of the running time update coefficient raw The value of the n+1th cylinder in [0,1,2…]; where r n [0](z) is the specific value of the running time update coefficient when the evaluation area is 0 in the previous sampling period; where k Adapt is the weighting coefficient, and k Adapt No more than k AdaptWeight Similarly, the updated running time update coefficients of other evaluation areas can be obtained, which is the updated running time update coefficient r n [0,1,2…,9].

6. A method for judging the oil injection action of a fixed cylinder oil circuit of an engine according to claim 5, characterized in that: The final running time is determined by: In the update flag bit b FirstAdaptDone When the value of is 0, the final running time T n-New is the running time; In the update flag bit b FirstAdaptDone When the value is 1, the final running time T n-New It is the product of the running time and the specific value of the updated running time update coefficient in the current evaluation area.

7. A method for judging the oil injection action of a fixed cylinder oil circuit of an engine according to claim 6, characterized in that: The method for obtaining the characteristic coefficient is as follows: the average final running time of each cylinder of the engine in a number of consecutive sampling cycles is T n_Avg , find the maximum value of the final running time average value as T max , the minimum value is T min The characteristic coefficient r CynDetectRaw For several consecutive sampling periods (T max -T min ) / T min The self-learning correction coefficient k Adapt The default initial value is 0, which will be saved after the vehicle is powered off.

8. The method for judging the oil injection action of the fixed cylinder oil circuit of an engine according to claim 7, characterized in that: The method for determining the value of the initial flag of the fixed cylinder based on the characteristic coefficient and the self-learning correction coefficient is as follows: CynDetectRaw (1+k Adapt )≥r CynDetectOffLim , then the initial flag bit bCynOffRaw The value is 1, otherwise the initial flag bCynOffRaw The value of is 0; CynDetectOffLim is a threshold coefficient for determining the continuous fuel cutoff of a fixed cylinder. The threshold coefficient is obtained by bench calibration. The specific method is as follows: the threshold coefficient is determined by the average engine speed and the average engine intake density. On the engine bench, the self-learning correction coefficient k Adapt Under the premise of being 0, read the characteristic coefficient r under the active oil cut-off condition CynDetectRaw and the characteristic coefficient r without oil cut-off CynDetectRaw The minimum value of the average value of the characteristic coefficient under the active oil cut-off condition and the characteristic coefficient under the non-oil cut-off condition obtained by multiple samplings is taken as the threshold coefficient r for judging the continuous oil cut-off of the fixed cylinder. CynDetectOffLim ; wherein the average engine speed and the average engine intake density are respectively the average values ​​of the current sampling cycle and the four sampling cycles before it, a total of five sampling cycles; according to the test bench, multiple samplings are performed, and the fixed cylinder continuous oil cut-off is actively set at different engine speeds and different engine intake densities, and the minimum value of the threshold coefficient obtained in multiple samplings is used as the threshold coefficient.

9. A method for judging the oil injection action of a fixed cylinder oil circuit of an engine according to claim 8, characterized in that: The method for determining the value of the flag bit of the fixed cylinder according to the value of the initial flag bit is: In the initial flag bCynOffRaw The value of is 1, if: The first case: There is a final running time average value T of the engine cylinder in several consecutive sampling cycles n_Avg With T max equal; and determine its cylinder number; Second case: Under the conditions of the first case, there is a preset value X>(T max -T n_Avg ) / T max >0, determine its cylinder number; The preset value X will be saved after the vehicle is powered off and will be continuously updated. Its default value is 0.08; The third case: the final running time (T n -T max ) / T max All are within the preset range ±Y; Y will be saved after the vehicle is powered off and continuously updated, and its default value is 0.08; The fourth case: at least one cylinder does not meet the first case or the second case; Fifth case: The cylinder numbers that meet the first or second case are recorded according to the cylinder working order. If the number of cylinders that do not meet the first or second case between two consecutive cylinder numbers that meet the first or second case is not less than 2, then T n_Avg With T min The equal cylinder number is not the next working cylinder number that satisfies the first condition or the second condition; If multiple sampling times Cnt CynoffDelay When the first, second, third, fourth, and fifth conditions are met under the above conditions, the initial fuel cut-off flag position b of the cylinder that meets the first or second condition is CynOff The value is 1, the initial fuel cut-off flag of other cylinders is b CynOff The value of is 0; The multiple sampling times Cnt CynoffDelay The initial default value is 8, 3≤Cnt CynoffDelay ≤15, and it will be saved after the vehicle is powered off.

10. A method for judging the oil injection action of a fixed cylinder oil circuit of an engine according to claim 9, characterized in that: The method for judging whether the engine cylinder whose initial fuel cut-off flag has a value of 1 has actually been fuel cut-off is: Actively cut off fuel for the cylinders that meet the first condition or the second condition, and re-obtain the final average running time T of each cylinder of the engine in the fuel cut-off state. n_AvgNew and the maximum value T of the average final running time of each cylinder of the engine in the fuel cut-off state maxNew With the minimum value T minNew ; (1) For the initial fuel cut-off flag b CynOff The value of the cylinder is 1, if and When the oil cut-off mark of this cylinder is b CynOffFuelCut =b CynOff =1, the multiple sampling times Cnt CynoffDelay Subtract 1 and save after power off, the self-learning correction coefficient k Adapt remain unchanged; Where C1 is the preset value; (2) For the initial fuel cut-off flag b CynOff For a cylinder with a value of 1, if and If only one of the following is satisfied, the oil cut-off flag of this cylinder is b CynOffFuelCut =0, the number of multiple sampling times Cnt CynoffDelay Remain unchanged; the self-learning correction coefficient And save it after power off; (3) For the initial fuel cut-off flag b CynOff The value of the cylinder is 1, if and If both are not satisfied, the oil cut-off mark of this cylinder is b CynOffFuelCut =0, the multiple sampling times Cnt CynoffDelay Add 2, the self-learning correction coefficient And save it after power off; (4) For the initial fuel cut-off flag b CynOff The value of cylinder A is 0. If the final running time average value of cylinder A is T A_Avg satisfy Then the oil cut-off mark of this cylinder is b CynOffFuelCut =0, the number of multiple sampling times Cnt CynoffDelay Remain unchanged, the self-learning correction coefficient And save after power off; C2 is the preset value; (5) In other cases, the cylinder oil cut-off mark is b CynOffFuelCut =0, the number of multiple sampling times Cnt CynoffDelay and the self-learning correction coefficient k Adapt remain unchanged; If the value of the initial fuel cut-off flag is 1, the fuel cut-off flag b of the engine cylinder CynOffFuelCut =1, it means that the engine cylinder has a real oil cut-off.

11. The method for judging the oil injection action of a fixed cylinder oil circuit of an engine according to claim 1, characterized in that: The enabling conditions of the method for judging the oil injection action of the fixed cylinder oil circuit of the engine 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; (4) The clutch is in full engagement; (5) Non-uneven road surface; (6) The water temperature is within the preset range; (7) The throttle opening fluctuation is small during the diagnosis process; (8) The engine is in operation; The gear position has not changed means that after the gear position changes, it takes a delay of more than the preset gear change time to activate the engine cylinder injection condition detection method; the clutch is in a fully engaged state means that after the clutch is engaged, it takes a delay of more than the preset clutch time to activate the engine cylinder injection condition detection method; the throttle opening fluctuation is small during the diagnosis process means that the throttle opening fluctuation is small during the diagnosis process means that the difference between the maximum opening and the minimum opening of the throttle within the preset throttle time is less than the preset throttle opening difference.

12. The method for judging the oil injection action of the fixed cylinder oil circuit of an engine according to claim 1, characterized in that: The fuel cut-off enabling conditions include: (1) satisfying the engine fuel injection performance detection enabling conditions; (2) The vehicle speed exceeds the preset value; (3) The engine does not experience knock and pre-ignition; (4) The exhaust temperature does not exceed the preset protection temperature; (5) The gasoline particulate filter does not request automatic regeneration; (6) The oxygen storage capacity of the catalyst does not exceed the preset coefficient of its total oxygen storage capacity; (7) No failure of components related to the fuel injection system occurs; (8) The difference between the average engine speed and the average engine speed obtained during the bench calibration process of the threshold coefficient is within a preset range; (9) The difference between the average engine intake density and the average intake density obtained during the bench calibration process of the threshold coefficient is within a preset range.

13. The method for judging the oil injection action of the fixed cylinder oil circuit of an engine according to claim 1, characterized in that: The runtime update optimization process activation conditions include: (1) The engine is in running state; (2) All cylinders of the engine are in the fuel cut-off state; (3) The engine does not directly participate in driving the vehicle; (4) The engine does not experience knock or pre-ignition; (5) The running time in several consecutive sampling periods is not 0; (6) The engine did not malfunction.

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