CN111237072A - An electronically controlled diesel engine nozzle fault identification method, system and electronic control unit - Google Patents

Abstract

The invention provides a method, system and electronic control unit for identifying a nozzle fault of an electronically controlled diesel engine. The method includes: when the electronically controlled diesel engine satisfies the nozzle detection conditions, acquiring nozzle detection parameters; and judging the first instantaneous rail pressure corresponding to each cylinder Whether the difference between the value and the second instantaneous rail pressure value is less than the preset rail pressure lower limit value; if so, judge whether the tooth period corresponding to each of the N crankshaft teeth is greater than the preset average value; Whether the number of cycles reaches the total number of cycles; if so, determine whether the abnormal number of times is greater than or equal to the limit value; if so, output a nozzle failure signal; wherein, if the difference is greater than or equal to the preset rail pressure lower limit, or if the If the tooth period is less than or equal to the preset average value, or, the number of cycles does not reach the total number of cycles, and the number of cycles is accumulated by 1, the nozzle detection parameters are re-acquired. It can avoid the loss of engine performance due to nozzle failure and ensure that the engine is not damaged.

Description

An electronically controlled diesel engine nozzle fault identification method, system and electronic control unit

technical field

The invention relates to the technical field of electronically controlled diesel engines, in particular to a method, system and electronic control unit for identifying faults of a nozzle of an electronically controlled diesel engine.

Background technique

With the development of science and technology, electronically controlled diesel engines have been widely used in daily life. In the structure of the electronically controlled diesel engine, the nozzle is an important part in the fuel supply system of the electronically controlled diesel engine to realize fuel injection. Combustion takes place in the cylinder.

The inventor's research found that in the prior art, after the nozzle of the electronically controlled diesel engine injector is blocked, the fault code cannot be reported directly through the Electronic Control Unit (ECU), and the fault location cannot be quickly located, even if the engine is found to be running. Abnormalities also need manual maintenance to finally confirm the cause of the failure. Since the fault location cannot be located in time, the continuous blockage of the injector nozzle will cause poor fuel injection, which will lead to insufficient engine power and affect engine performance.

SUMMARY OF THE INVENTION

In view of this, the embodiments of the present invention provide a method, system and electronic control unit for identifying faults of an electronically controlled diesel engine nozzle, which solve the problem of insufficient engine power due to the inability to quickly locate the clogging fault position of the electronically controlled diesel engine nozzles, which in turn affects the problem. engine performance issues.

To achieve the above purpose, the embodiments of the present invention provide the following technical solutions:

A method for identifying faults of an electronically controlled diesel engine nozzle, the method comprising:

Under the condition that the electronically controlled diesel engine satisfies the nozzle detection conditions, acquire the nozzle detection parameters, where the nozzle detection parameters at least include the first instantaneous rail pressure value and the injection value of each cylinder of the electronically controlled diesel engine at the first moment before fuel injection. The second instantaneous rail pressure value at the second moment after the oil, and the corresponding tooth period of the N crankshaft teeth after the top dead center of each cylinder, the value of N is based on the total number of cylinders and cylinders of the electronically controlled diesel engine The instantaneous acceleration after normal ignition is determined;

judging whether the difference between the first instantaneous rail pressure value and the second instantaneous rail pressure value corresponding to each of the cylinders is smaller than a preset rail pressure lower limit value;

If it is less than the preset rail pressure lower limit value, determine whether the respective tooth periods corresponding to the N crankshaft teeth are greater than the preset average value;

If it is greater than the preset average value, the number of abnormality is accumulated by 1, and it is judged whether the number of cycles reaches the total number of cycles;

If the total number of cycles is reached, determine whether the abnormal number of times is greater than or equal to the limit value;

If it is greater than or equal to the limit value, output nozzle fault signal;

Wherein, if the difference value is greater than or equal to the preset rail pressure lower limit value, or, if the tooth period corresponding to each of the N crankshaft teeth is less than or equal to the preset average value, or the number of cycles does not reach the total number of cycles, The number of cycles is incremented by 1, and the process returns to the step of acquiring the nozzle detection parameters.

Optionally, also include:

If the number of abnormality is less than the limit value, clear the number of cycles and the number of abnormality to zero;

Confirm whether the electronically controlled diesel engine is under the condition that the nozzle detection conditions are met;

If so, return to the step of obtaining the nozzle detection parameters.

Optionally, the nozzle detection conditions include:

The engine speed of the electronically controlled diesel engine is in a stable state and the engine phases are synchronized, the change value of the intake air flow of the electronically controlled diesel engine is within a preset range, and the release state of the injectors of each cylinder of the electronically controlled diesel engine is The release state and the fuel injector have no electrical fault signal output.

Optionally, the process of setting the preset rail pressure lower limit value includes:

Based on the power-on time and the rail pressure value, a rail pressure drop value in a normal state is obtained, the power-on time refers to the time to drive the fuel injector, and the rail pressure drop value refers to the first time before fuel injection of the cylinder The difference between the instantaneous rail pressure values within the segment and the second time segment after fuel injection;

The minimum value of the obtained rail pressure drop values is used as the preset rail pressure lower limit value.

Optionally, the setting process of the preset average value includes:

Obtain the tooth period corresponding to each of the N crankshaft teeth after the top dead center of each cylinder in a normal state;

Calculate the average value of the tooth period corresponding to each of the N crankshaft teeth, and use the average value as a preset average value.

An electronically controlled diesel engine nozzle fault identification system, the system comprising:

a detection unit for detecting whether the electronically controlled diesel engine meets the nozzle detection conditions, and executes the acquisition unit when the electronically controlled diesel engine meets the nozzle detection conditions;

The acquisition unit is used to acquire nozzle detection parameters, the nozzle detection parameters at least include the first instantaneous rail pressure value of each cylinder of the electronically controlled diesel engine at the first moment before fuel injection and the second moment after fuel injection. The second instantaneous rail pressure value, and the tooth period corresponding to each of the N crankshaft teeth after the top dead center of each cylinder is obtained, and the value of N is based on the total number of cylinders of the electronically controlled diesel engine and the instantaneous acceleration after the cylinders are normally fired Sure;

A judging unit for judging whether the difference between the first instantaneous rail pressure value and the second instantaneous rail pressure value corresponding to each of the cylinders is less than a preset rail pressure lower limit value, and if it is less than a preset rail pressure lower limit value The lower limit value of rail pressure, to judge whether the tooth period corresponding to each of the N crankshaft teeth is greater than the preset average value, if it is greater than the preset average value, call the abnormal times counting unit, and judge whether the cycle times reach the total The total number of cycles, to judge whether the abnormal times is greater than or equal to the limit value, if it is greater than or equal to the limit value, execute the fault reminder unit, wherein, if the difference value is greater than or equal to the preset rail pressure lower limit value, or, if the N If the tooth period corresponding to each of the crankshaft teeth is less than or equal to the preset average value, or, the number of cycles does not reach the total number of cycles, the cycle number counting unit is invoked, and the obtaining unit continues to be executed;

an abnormal number counting unit, used for accumulating the abnormal number of times, and accumulating the abnormal number of times by 1 each time it is called;

a cycle count counting unit, used for accumulating the cycle times, and accumulating the cycle times by 1 each time it is called;

The fault reminding unit is used for outputting a nozzle fault signal.

Optionally, the judging unit is further configured to execute a clearing unit if the abnormal number of times is less than a limit value;

The clearing unit is configured to clear the number of cycles and the number of abnormality to zero, and continue to execute the detection unit.

Optionally, also include:

The first setting unit is used to obtain the rail pressure drop value in a normal state based on the power-on time and the rail pressure value, the power-on time refers to the time to drive the fuel injector, and the rail pressure drop value refers to the cylinder in the The difference between the instantaneous rail pressure values in the first time period before fuel injection and the second time period after fuel injection is the minimum value of the obtained rail pressure drop values as the preset rail pressure lower limit value.

Optionally, also include:

The second setting unit is configured to obtain the tooth periods corresponding to the N crankshaft teeth after the top dead center of each cylinder in a normal state, calculate the average value of the corresponding tooth periods of the N crankshaft teeth, and use the average value as the preset value. Set the average value.

An electronic control unit ECU, the ECU includes a processor and a memory, wherein a computer program is stored in the memory, and the processor is used to call the computer program in the memory to execute the above-mentioned method for identifying faults of an electronically controlled diesel engine nozzle .

Compared with the prior art, the present invention has the following beneficial effects:

An embodiment of the present invention provides a method for identifying a nozzle fault of an electronically controlled diesel engine. The method obtains a nozzle detection parameter when the electronically controlled diesel engine meets the nozzle detection condition, and the nozzle detection parameter at least includes the information of the electronically controlled diesel engine. The first instantaneous rail pressure value of each cylinder at the first moment before fuel injection and the instantaneous rail pressure value at the second moment after fuel injection, and the respective tooth periods corresponding to the N crankshaft teeth after the top dead center of each cylinder are obtained , the value of N is determined based on the total number of cylinders of the electronically controlled diesel engine and the instantaneous acceleration after the cylinders are normally fired; determine the first instantaneous rail pressure value and the second instantaneous rail pressure corresponding to the respective cylinders Whether the difference between the values is smaller than the preset rail pressure lower limit value; if it is smaller than the preset rail pressure lower limit value, determine whether the respective tooth periods corresponding to the N crankshaft teeth are larger than the preset average value; if it is larger than the preset average value If it reaches the total number of cycles, determine whether the abnormal number is greater than or equal to the limit value; if it is greater than or equal to the limit value, output a nozzle fault signal; The value is greater than or equal to the preset rail pressure lower limit value, or, if the respective tooth periods corresponding to the N crankshaft teeth are less than or equal to the preset average value, or, the number of cycles does not reach the total number of cycles, the number of cycles is accumulated by 1 , and return to the step of obtaining nozzle detection parameters. Using the method provided by the embodiment of the present invention, according to the change of rail pressure before and after fuel injection of each cylinder and the instantaneous acceleration after normal ignition, when it is found that the injector nozzle is blocked, a fault is reported in time, and the relevant personnel are reminded to check the injector nozzle. Troubleshooting to avoid engine performance loss and safety hazards caused by the fault, so as to ensure that the engine is not damaged.

Description of drawings

In order to explain the embodiments of the present invention or the technical solutions in the prior art more clearly, the following briefly introduces the accompanying drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only It is an embodiment of the present invention. For those of ordinary skill in the art, other drawings can also be obtained according to the provided drawings without creative work.

FIG. 1 provides a flowchart of a method for identifying faults of an electronically controlled diesel engine nozzle according to an embodiment of the present invention;

2 is a flowchart of another method of a method for identifying faults of an electronically controlled diesel engine nozzle according to an embodiment of the present invention;

3 is a flow chart of another method of a method for identifying faults of an electronically controlled diesel engine nozzle according to an embodiment of the present invention;

FIG. 4 provides a structural block diagram of an electronically controlled diesel engine nozzle fault identification system according to an embodiment of the present invention;

FIG. 5 is a structural block diagram of an electronic control unit ECU according to an embodiment of the present invention.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

In this application, the terms "comprising", "comprising" or any other variation thereof are intended to encompass a non-exclusive inclusion such that a process, method, article or device comprising a list of elements includes not only those elements, but also no Other elements expressly listed, or which are also inherent to such a process, method, article or apparatus. Without further limitation, an element qualified by the phrase "comprising a..." does not preclude the presence of additional identical elements in a process, method, article or apparatus that includes the element.

As shown in FIG. 1 , an embodiment of the present invention provides a method for identifying faults of an electronically controlled diesel engine nozzle, which may include the following steps:

S101: Detect whether the electronically controlled diesel engine meets the nozzle detection condition, if not, continue to return to S101, and if so, execute S102.

In S101, the nozzle detection conditions may include: the engine speed of the electronically controlled diesel engine is in a stable state, and the engine phase is synchronized, the change value of the intake air flow of the electronically controlled diesel engine is within a preset range, the injection of each cylinder of the electronically controlled diesel engine The release state of the fuel injector is in the released state, and the fuel injector has no electrical fault signal output.

If the electronically controlled diesel engine satisfies the nozzle detection conditions, obtain the nozzle detection parameters; if the electronically controlled diesel engine does not meet the nozzle detection conditions, continue to return to S101 to detect whether the electronically controlled diesel engine meets the nozzle detection conditions.

Specifically, the nozzle detection conditions may also include good operation of various components of the engine, and the nozzle detection conditions may be determined according to circumstances, which are not further limited in this application.

S102: Obtain nozzle detection parameters.

In S102, the nozzle detection parameters at least include a first instantaneous rail pressure value of each cylinder of the electronically controlled diesel engine at a first moment before fuel injection and a second instantaneous rail pressure value at a second moment after fuel injection, and the obtained The respective tooth periods corresponding to the N crankshaft teeth after the top dead center of each cylinder, the value of N is determined based on the total number of cylinders of the electronically controlled diesel engine and the instantaneous acceleration after the cylinders are normally fired. Regarding the value of N, the value of N varies according to the structure of different electronically controlled diesel engines.

Specifically, the rail pressure value of each cylinder will change before and after fuel injection. The rail pressure value at the first moment before fuel injection can be used as the first instantaneous rail pressure value, and the rail pressure value at the second moment after fuel injection can be used as the first momentary rail pressure value. 2. Instantaneous rail pressure value.

The tooth period corresponding to each of the N crankshaft teeth after the top dead center of each cylinder refers to the time corresponding to each of the angles rotated by the N crankshaft teeth after the cylinder is normally fired.

S103: Determine whether the difference between the first instantaneous rail pressure value and the second instantaneous rail pressure value corresponding to each of the cylinders is smaller than a preset rail pressure lower limit value, and if it is smaller than a preset rail pressure lower limit If the limit value is greater than or equal to the preset rail pressure lower limit value, execute S104, and execute S101.

In S103, the first instantaneous rail pressure value and the second instantaneous rail pressure corresponding to each cylinder are obtained by making the difference between the first instantaneous rail pressure value and the second rail pressure value corresponding to each cylinder respectively. The difference between the values is compared, and each obtained difference is compared with the preset rail pressure lower limit value to determine whether the difference is smaller than the preset rail pressure lower limit value.

If the difference is less than the preset lower limit of rail pressure, it is further judged whether the tooth period corresponding to each of the N crankshaft teeth is greater than the preset average value; if the difference is greater than or equal to the preset lower limit of rail pressure, return to S101 Execute to detect whether the electronically controlled diesel engine is in the condition to meet the nozzle detection.

S104: Determine whether the tooth period corresponding to each of the N crankshaft teeth is greater than a preset average value, if yes, execute S105, and if not, execute S101.

In S104, if the difference between the first instantaneous rail pressure value and the second instantaneous rail pressure value in S103 is smaller than the preset rail pressure lower limit value, it is further determined whether the tooth period corresponding to each of the N crankshaft teeth is greater than the preset value average value.

If the tooth period corresponding to each of the N crankshaft teeth is greater than the preset average value, the abnormal times will be accumulated by 1, that is, an abnormal frequency record will be added on the basis of the original abnormal times; if the corresponding tooth periods of the N crankshaft teeth are less than or equal to the preset value If the average value is obtained, return to S101 to detect whether the electronically controlled diesel engine meets the nozzle detection condition.

S105: The abnormal times are accumulated by 1, and it is judged whether the number of cycles reaches the total number of cycles, if so, execute S106; if not, execute S101.

In S105, if the tooth period corresponding to each of the N crankshaft teeth in S104 is greater than the preset average value, the abnormality is recorded in the storage device associated with the engine electronic control unit ECU by means of accumulation.

For example, when the respective tooth periods corresponding to the N crankshaft teeth are greater than the preset average value, 1 is accumulated on the basis of the original abnormal times. Subsequently, it is further judged whether the number of cycles reaches the total number of cycles, and if the number of cycles has reached the total number of cycles, it is further judged whether the number of abnormality is greater than or equal to the limit value; if the number of cycles does not reach the total number of cycles, return to S101 to detect whether the electronically controlled diesel engine is The nozzle detection conditions are met. When setting the total number of cycles, it can be set according to the field test effect, which is not further limited in this application.

S106: Determine whether the abnormal number of times is greater than or equal to the limit value, if yes, execute S107, and if not, execute S108.

In S106, if the number of cycles reaches the total number of cycles, it is further judged whether the abnormal number of times is greater than or equal to the limit value. The limit value can be set by the technician before the engine leaves the factory, or can be set by the relevant personnel using the engine according to the aging of the engine. situation to be set. For example, before the engine leaves the factory, because the engine has less nozzle blockage, the technician can set the limit value to 2, and later due to the aging of the engine and more failures, the relevant personnel can set the limit value to 4.

When the number of cycles does not reach the total number of cycles, 1 is accumulated on the basis of the previously recorded number of cycles, and then returns to S101 to detect whether the electronically controlled diesel engine meets the nozzle detection conditions.

S107: Output the nozzle failure signal.

In S107, when the number of abnormality is greater than or equal to the limit value, a nozzle fault signal is output, and the signal is used to remind relevant personnel to check the injector nozzle fault, so as to avoid engine performance loss and potential safety hazards caused by the fault, so as to ensure The engine is not damaged.

It should be noted that one engine nozzle fault detection may include multiple cycles. The execution of the engine electronic control unit ECU from S101 to the end of S107 is one cycle. One cycle can be two revolutions of the crankshaft and one revolution of the camshaft. In the next cycle, each cylinder works once.

S108: Clear the cycle times and the abnormal times to zero.

In S108, if the abnormal count is less than the limit value, the cycle count and the abnormal count are cleared to zero. After the cycle times and abnormal times are cleared to zero, the current engine nozzle fault detection ends. In the next engine nozzle fault detection, the number of cycles and abnormal times can be re-recorded, so as to avoid counting disorder and cause the engine to generate false alarms of nozzle faults.

In the next engine nozzle fault detection, confirm whether the electronically controlled diesel engine meets the nozzle detection conditions. If the electronically controlled diesel engine meets the engine nozzle fault detection conditions, re-acquire the nozzle detection parameters. It should be noted that the execution and termination in the order from S101, S102, S103, S104, S105, S106, and S108 may be one cycle.

In the method for identifying a nozzle fault of an electronically controlled diesel engine provided by the embodiment of the present invention, when the electronically controlled diesel engine meets the nozzle detection conditions, the nozzle detection parameters are obtained, and the first instantaneous rail pressure value corresponding to each cylinder is determined. Whether the difference between the second instantaneous rail pressure value and the second instantaneous rail pressure value is smaller than the preset rail pressure lower limit value; if it is smaller than the preset rail pressure lower limit value, determine whether the tooth period corresponding to each of the N crankshaft teeth is larger than the preset rail pressure value Average value; if it is greater than the preset average value, the number of abnormality is accumulated by 1, and it is judged whether the number of cycles reaches the total number of cycles; if it reaches the total number of cycles, it is judged whether the number of abnormality is greater than or equal to the limit value; if it is greater than or equal to the limit value, the output nozzle is faulty signal; wherein, if the difference is greater than or equal to the preset rail pressure lower limit value, or, if the tooth period corresponding to each of the N crankshaft teeth is less than or equal to the preset average value, or the number of cycles does not reach the total number of cycles number, the number of cycles is incremented by 1, and the process returns to the step of acquiring the nozzle detection parameters. Using the method for identifying faults of electronically controlled diesel engine nozzles provided by the embodiment of the present invention, according to the change of rail pressure before and after fuel injection of each cylinder and the instantaneous acceleration after normal ignition, when it is found that the nozzle of the fuel injector is blocked, the fault will be reported in time, and the relevant information will be reminded. The personnel checked the failure of the injector nozzle to avoid the loss of engine performance and potential safety hazards caused by the failure, so as to ensure that the engine was not damaged.

As shown in FIG. 2 , in the method for identifying faults of an electronically controlled diesel engine nozzle provided by an embodiment of the present invention, based on the implementation process of S103 above, specifically, the process of setting the preset rail pressure lower limit value may include:

S201: Obtain a rail voltage drop value in a normal state based on the power-on time and the rail voltage value.

In S201, in the normal state of the engine, the rail pressure drop value is related to the power-on time and the rail pressure value. By executing S201, multiple rail voltage drop values based on different power-on times and rail voltage values may be acquired.

The power-on time refers to the time to drive the fuel injector, and the rail pressure drop value refers to the difference between the instantaneous rail pressure values of the cylinder in the first time before fuel injection and the second time after fuel injection.

It should be noted that, under normal circumstances, each time the nozzle injects fuel, the rail pressure will drop instantly. Under the same rail pressure, the longer the power-on time is, the more external fuel is injected, and the more the rail pressure drops instantly. If the rail pressure does not drop or the rail pressure drop is too small, it means that there is no actual fuel injection or the fuel injection amount does not match the power-on time. S202: Use the minimum value of the obtained rail pressure drop values as a preset rail pressure lower limit value.

In S202, according to the obtained rail voltage drop values under different power-on time conditions, determine the minimum rail voltage drop value among them, and use it as the rail pressure lower limit value.

By applying the method for identifying faults of an electronically controlled diesel engine nozzle provided by the embodiment of the present invention, the lower limit value of the rail pressure under normal conditions of the engine can be set, so as to be consistent with the first instantaneous rail pressure value before the fuel injector and the second rail pressure value before fuel injection. The difference between the instantaneous rail pressure values is compared to determine whether the rail pressure changes before and after the fuel injector is normal.

As shown in FIG. 3 , in the method for identifying faults of an electronically controlled diesel engine nozzle provided by an embodiment of the present invention, in the implementation process of the above S104, specifically, the setting process of the preset average value may include:

S301: Acquire the tooth periods corresponding to the N crankshaft teeth after the top dead center of each cylinder in a normal state.

In S301, in a normal state of the engine, the tooth periods corresponding to the N crankshaft teeth after the top dead center of each cylinder are acquired.

Among them, the value of N is determined by the total number of cylinders of the electronically controlled diesel engine and the instantaneous acceleration after the normal ignition of the cylinder.

It should be noted that, for the value of N, the value of N varies according to the different structures of different electronically controlled diesel engines. It can be considered that N is fixed for a single engine model, and the value is different for different engine models. For example: the engine model is 4 cylinders, the number of crankshaft teeth is 4, and the angle of each crankshaft tooth is 6 degrees, then the 4 crankshaft teeth correspond to 24 degrees. For a 4-cylinder engine, after any cylinder ignites normally, the acceleration of the cylinder will increase instantaneously within a certain angle. Based on this angle and the angle of the crankshaft teeth, the value of N is determined. For example, the angle of this section is 12 degrees, then the value of N can be 2.

For example: the engine model is 6 cylinders, the number of crankshaft teeth is 6, and the angle of each crankshaft tooth is 6 degrees, then the 6 crankshaft teeth correspond to 36 degrees. For a 6-cylinder engine, after any cylinder ignites normally, the acceleration of the cylinder will also increase instantaneously within a certain angle. Based on this angle and the angle of the crankshaft teeth, the value of N is determined. For example, the angle of this section is 24 degrees, then the value of N can be 4.

S302: Calculate the average value of the tooth periods corresponding to each of the N crankshaft teeth, and use the average value as a preset average value.

In S302, an average value of the tooth periods corresponding to each of the N crankshaft teeth is calculated, and the average value is used as a preset average value. For example, the time required to record the N crankshaft teeth with the most obvious acceleration after the top dead center of each cylinder is Ti, i represents the cylinder number, and Ti can reflect the single-cylinder acceleration of each cylinder. The smaller the Ti, the higher the single-cylinder acceleration. sooner.

Specifically, the time average Ta of all cylinders can be obtained by dividing the sum of Ti of all cylinders by the number of cylinders.

By applying the method for identifying faults of an electronically controlled diesel engine nozzle provided by the embodiment of the present invention, the preset average value under the normal state of the engine is set, so as to be compared with the respective tooth periods corresponding to the N crankshaft teeth after the top dead center of each cylinder, thereby Determine whether the respective tooth periods corresponding to the N crankshaft teeth after the top dead center of each cylinder are normal.

Corresponding to the above method embodiments, the embodiment of the present invention provides an electronically controlled diesel engine nozzle fault identification system, the structure of which is shown in FIG. 4 , and the electronically controlled diesel engine nozzle fault identification system 400 may include:

A detection unit 401, configured to detect whether the electronically controlled diesel engine meets the nozzle detection condition, and execute the acquisition unit when the electronically controlled diesel engine meets the nozzle detection condition;

The acquisition unit 402 is configured to acquire nozzle detection parameters, the nozzle detection parameters at least include the first instantaneous rail pressure value of each cylinder of the electronically controlled diesel engine at the first moment before fuel injection and the second moment after fuel injection. The instantaneous rail pressure value, and the tooth period corresponding to each of the N crankshaft teeth after the top dead center of each cylinder is obtained. The value of N is determined based on the total number of cylinders of the electronically controlled diesel engine and the instantaneous acceleration after the cylinders are normally fired. ;

The judgment unit 403 is used for judging whether the difference between the first instantaneous rail pressure value and the second instantaneous rail pressure value corresponding to each cylinder is smaller than the preset rail pressure lower limit value, if it is smaller than the preset rail pressure lower limit value. Set the lower limit value of rail pressure, and judge whether the tooth period corresponding to each of the N crankshaft teeth is greater than the preset average value. When the total number of cycles is reached, it is judged whether the abnormal number of times is greater than or equal to the limit value, and if it is greater than or equal to the limit value, a fault reminder unit is executed, wherein, if the difference value is greater than or equal to the preset rail pressure lower limit value, or if the N The tooth period corresponding to each of the crankshaft teeth is less than or equal to the preset average value, or, the cycle number does not reach the total number of cycles, call the cycle number counting unit, and continue to execute the obtaining unit;

The abnormal times counting unit 404 is used for accumulating the abnormal times, and accumulating the abnormal times by 1 every time the abnormal times are called;

The number of cycles counting unit 405 is used for accumulating the number of cycles, and the number of cycles is incremented by 1 each time it is called;

The fault reminding unit 406 is used for outputting a nozzle fault signal.

In the electronically controlled diesel engine nozzle fault identification system provided by the embodiment of the present invention, when the electronically controlled diesel engine meets the nozzle detection conditions, the nozzle detection parameters are obtained, and the first instantaneous rail pressure value corresponding to each cylinder is determined. Whether the difference between the second instantaneous rail pressure value and the second instantaneous rail pressure value is smaller than the preset rail pressure lower limit value; if it is smaller than the preset rail pressure lower limit value, determine whether the tooth period corresponding to each of the N crankshaft teeth is larger than the preset rail pressure value Average value; if it is greater than the preset average value, the number of abnormality is accumulated by 1, and it is judged whether the number of cycles reaches the total number of cycles; if it reaches the total number of cycles, it is judged whether the number of abnormality is greater than or equal to the limit value; if it is greater than or equal to the limit value, the output nozzle is faulty signal; wherein, if the difference is greater than or equal to the preset rail pressure lower limit value, or, if the tooth period corresponding to each of the N crankshaft teeth is less than or equal to the preset average value, or the number of cycles does not reach the total number of cycles number, the number of cycles is incremented by 1, and the process returns to the step of acquiring the nozzle detection parameters. Using the electronically controlled diesel engine nozzle fault identification system provided by the embodiment of the present invention, according to the change of rail pressure before and after fuel injection of each cylinder and the instantaneous acceleration after normal ignition, when it is found that the nozzle of the fuel injector is blocked, the fault will be reported in time, and the relevant information will be reminded. The personnel checked the failure of the injector nozzle to avoid the loss of engine performance and potential safety hazards caused by the failure, so as to ensure that the engine was not damaged.

In the above-mentioned electronically controlled diesel engine nozzle fault identification system, the judging unit 403 is further configured to execute the zero-clearing unit 407 if the abnormal number of times is less than the limit value;

The clearing unit 407 is configured to clear the cycle times and the abnormal times to zero, and continue to execute the detection unit.

The above-mentioned electronically controlled diesel engine nozzle fault identification system further includes:

The first setting unit 408 is configured to obtain rail pressure drop values under different power-on time conditions in a normal state based on the power-on time and the rail pressure value, where the power-on time refers to the time for driving the fuel injector, and the rail pressure The drop value refers to the difference between the instantaneous rail pressure values of the cylinder in the first time period before fuel injection and in the second time period after fuel injection, and the minimum value of the obtained rail pressure drop values is used as the preset rail. Lower limit value.

The above-mentioned electronically controlled diesel engine nozzle fault identification system further includes:

The second setting unit 409 is configured to obtain the tooth period corresponding to each of the N crankshaft teeth after the top dead center of each cylinder in a normal state, calculate the average value of the tooth period corresponding to each of the N crankshaft teeth, and use the average value as Default average.

By applying the electronically controlled diesel engine fault identification system provided by the embodiment of the present invention, the change of the rail pressure value before and after the fuel injection of each cylinder and the corresponding tooth period of the N crankshaft teeth are obtained, so as to identify whether the injector nozzle is blocked, and report the time. If there is a fault, remind the relevant personnel to check the fault of the injector nozzle, so as to avoid the loss of engine performance and potential safety hazards caused by the fault, so as to ensure that the engine is not damaged.

Referring to FIG. 5 , it is a block diagram of an electronic control unit ECU for controlling an electronically controlled diesel engine fault identification system for detection according to an embodiment of the present invention. The electronic control unit is applied in a detection device of an electronically controlled diesel engine identification system, and the ECU includes: Processor 501 and memory 502.

A computer program is stored in the memory, and the processor is used to execute the computer program stored in the memory 502 to realize the detection of the electronically controlled diesel engine fault identification system. The realization process is as follows:

Specifically, the processor executes the computer program stored in the memory to realize the detection process of the electronically controlled diesel engine fault identification system as follows: when the electronically controlled diesel engine meets the nozzle detection conditions, obtain the nozzle detection parameters, and the nozzle detection parameters at least include The first instantaneous rail pressure value of each cylinder of the electronically controlled diesel engine at the first moment before fuel injection and the second instantaneous rail pressure value at the second moment after fuel injection, and the N after the top dead center of each cylinder is obtained. The tooth period corresponding to each crankshaft tooth, and the value of N is determined based on the total number of cylinders of the electronically controlled diesel engine and the instantaneous acceleration after the cylinder is normally fired; the first instantaneous rail pressure value corresponding to each cylinder is determined. Whether the difference between the second instantaneous rail pressure value and the second instantaneous rail pressure value is smaller than the preset rail pressure lower limit value; if it is smaller than the preset rail pressure lower limit value, determine whether the tooth period corresponding to each of the N crankshaft teeth is larger than the preset rail pressure value Average value; if it is greater than the preset average value, the number of abnormality is accumulated by 1, and it is judged whether the number of cycles reaches the total number of cycles; if it reaches the total number of cycles, it is judged whether the number of abnormality is greater than or equal to the limit value; if it is greater than or equal to the limit value, the output nozzle is faulty signal; wherein, if the difference is greater than or equal to the preset rail pressure lower limit value, or, if the tooth period corresponding to each of the N crankshaft teeth is less than or equal to the preset average value, or the number of cycles does not reach the total number of cycles number, the number of cycles is incremented by 1, and returns to obtain the nozzle detection parameters.

Using the engine electronic control unit ECU provided by the embodiment of the present invention, according to the change of rail pressure before and after fuel injection of each cylinder and the instantaneous acceleration after normal ignition, when it is found that the nozzle of the fuel injector is blocked, a fault will be reported in time, and the relevant personnel will be reminded. Investigate the failure of the injector nozzle to avoid the loss of engine performance and potential safety hazards caused by the failure, so as to ensure that the engine is not damaged.

The above description of the disclosed embodiments enables any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims (10)

1. an electronically controlled diesel engine nozzle fault identification method, is characterized in that, described method comprises: Under the condition that the electronically controlled diesel engine satisfies the nozzle detection conditions, acquire the nozzle detection parameters, where the nozzle detection parameters at least include the first instantaneous rail pressure value and the injection value of each cylinder of the electronically controlled diesel engine at the first moment before fuel injection. The second instantaneous rail pressure value at the second moment after the oil, and the corresponding tooth period of the N crankshaft teeth after the top dead center of each cylinder, the value of N is based on the total number of cylinders and cylinders of the electronically controlled diesel engine The instantaneous acceleration after normal ignition is determined; judging whether the difference between the first instantaneous rail pressure value and the second instantaneous rail pressure value corresponding to each of the cylinders is smaller than a preset rail pressure lower limit value; If it is less than the preset rail pressure lower limit value, determine whether the respective tooth periods corresponding to the N crankshaft teeth are greater than the preset average value; If it is greater than the preset average value, the number of abnormality is accumulated by 1, and it is judged whether the number of cycles reaches the total number of cycles; If the total number of cycles is reached, determine whether the abnormal number of times is greater than or equal to the limit value; If it is greater than or equal to the limit value, output nozzle fault signal; Wherein, if the difference value is greater than or equal to the preset rail pressure lower limit value, or, if the tooth period corresponding to each of the N crankshaft teeth is less than or equal to the preset average value, or the number of cycles does not reach the total number of cycles, The number of cycles is incremented by 1, and the process returns to the step of acquiring the nozzle detection parameters. 2. The method of claim 1, further comprising: If the number of abnormality is less than the limit value, clear the number of cycles and the number of abnormality to zero; Confirm whether the electronically controlled diesel engine is under the condition that the nozzle detection conditions are met; If so, return to the step of obtaining the nozzle detection parameters. 3. The method according to claim 1, wherein the nozzle detection conditions comprise: The engine speed of the electronically controlled diesel engine is in a stable state and the engine phases are synchronized, the change value of the intake air flow of the electronically controlled diesel engine is within a preset range, and the release state of the injectors of each cylinder of the electronically controlled diesel engine is The release state and the fuel injector have no electrical fault signal output. 4. The method according to claim 1, wherein the setting process of the preset rail pressure lower limit value comprises: Based on the power-on time and the rail pressure value, obtain the rail pressure drop value in a normal state, the power-on time refers to the time to drive the fuel injector, and the rail pressure drop value refers to the first time before fuel injection of the cylinder The difference between the instantaneous rail pressure values in the period and in the second time period after fuel injection; The minimum value of the obtained rail pressure drop values is used as the preset rail pressure lower limit value. 5. The method according to claim 1, wherein the setting process of the preset average value comprises: Obtain the tooth period corresponding to each of the N crankshaft teeth after the top dead center of each cylinder under normal conditions; The average value of the tooth periods corresponding to each of the N crankshaft teeth is calculated, and the average value is used as a preset average value. 6. An electronically controlled diesel engine nozzle fault identification system, characterized in that the system comprises: a detection unit, configured to detect whether the electronically controlled diesel engine is in the condition of satisfying the nozzle detection condition, and execute the acquisition unit when the electronically controlled diesel engine is in the condition of satisfying the nozzle detection condition; The acquisition unit is used to acquire nozzle detection parameters, the nozzle detection parameters at least include the first instantaneous rail pressure value of each cylinder of the electronically controlled diesel engine at the first moment before fuel injection and the second moment after fuel injection. The second instantaneous rail pressure value, and the tooth period corresponding to each of the N crankshaft teeth after the top dead center of each cylinder is obtained, and the value of N is based on the total number of cylinders of the electronically controlled diesel engine and the instantaneous acceleration of the cylinder after normal ignition Sure; A judging unit for judging whether the difference between the first instantaneous rail pressure value and the second instantaneous rail pressure value corresponding to each of the cylinders is smaller than a preset rail pressure lower limit value, if it is smaller than a preset rail pressure lower limit value The lower limit value of rail pressure is used to judge whether the tooth period corresponding to each of the N crankshaft teeth is greater than the preset average value. The total number of cycles, to determine whether the abnormal times is greater than or equal to the limit value, if it is greater than or equal to the limit value, execute the fault reminder unit, wherein, if the difference value is greater than or equal to the preset rail pressure lower limit, or if the N If the tooth period corresponding to each of the crankshaft teeth is less than or equal to the preset average value, or, the number of cycles does not reach the total number of cycles, the cycle number counting unit is invoked, and the obtaining unit continues to be executed; an abnormal number counting unit, used for accumulating the abnormal number of times, and accumulating the abnormal number of times by 1 each time it is called; a cycle count counting unit, used for accumulating the cycle times, and accumulating the cycle times by 1 each time it is called; The fault reminding unit is used for outputting a nozzle fault signal. 7. The system according to claim 6, wherein the judging unit is further configured to execute a clearing unit if the abnormal number of times is less than a limit value; The clearing unit is configured to clear the number of cycles and the number of abnormality to zero, and continue to execute the detection unit. 8. The system of claim 6, further comprising: The first setting unit is used to obtain the rail pressure drop value in a normal state based on the power-on time and the rail pressure value, the power-on time refers to the time to drive the fuel injector, and the rail pressure drop value refers to the cylinder in the The difference between the instantaneous rail pressure values in the first time period before fuel injection and in the second time period after fuel injection, the minimum value of the obtained rail pressure drop values is used as the preset rail pressure lower limit value. 9. The system of claim 6, further comprising: The second setting unit is configured to obtain the tooth period corresponding to each of the N crankshaft teeth after the top dead center of each cylinder in a normal state, calculate the average value of the tooth period corresponding to each of the N crankshaft teeth, and use the average value as a preset Set the average value. 10. An electronic control unit ECU, characterized in that the ECU comprises a processor and a memory, the memory stores a computer program, and the processor is used to call the computer program in the memory to execute claims 1 to 5 Any one of the methods for identifying faults of an electronically controlled diesel engine nozzle.

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