A rail pressure-based fuel injector fault diagnosis method and device, storage medium and processor

Abstract

The application discloses a rail pressure-based fuel injector fault diagnosis method and device, a storage medium and a processor, and comprises the following steps: collecting real-time rail pressure data and fuel injection quantity of each fuel injector in one working cycle of a current diesel engine; obtaining the cylinder number of the current diesel engine; calculating the rail pressure variation coefficient of the current fuel injector based on the cylinder number, the real-time rail pressure data and the fuel injection quantity; and comparing the rail pressure variation coefficient with a preset rail pressure variation threshold value, and determining that the current fuel injector has a fault in the case that the rail pressure variation coefficient is greater than the preset rail pressure variation threshold value. The above process determines whether the fuel injector has a fault based on the rail pressure variation coefficient, avoids the problem that the fuel injector cannot be protected when being stuck in the 'off position due to the fuel injector stuck protection of hardware, cannot be reset and the fuel injection quantity changes rapidly, and the pressure in the pressure accumulation cavity changes rapidly, causing abnormal seating of the small ball and abnormal closing of injection.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of fault diagnosis, and in particular to a fuel injector fault diagnosis method and device based on rail pressure, a storage medium and a processor. BACKGROUND

[0002] The fuel injector may be stuck at a certain position due to foreign matter, fuel injector internal electromagnetic switch failure, etc. If stuck at the "closed" position, the fuel injector is always closed, and the single cylinder stops fuel supply, which may cause uneven combustion of each cylinder, speed fluctuation, etc. If stuck at the "open" position, the fuel injector is always open, and the single cylinder continuously supplies fuel, which may cause black smoke, single cylinder temperature rise, speed fluctuation, etc. It may also cause the diesel engine to lose control and fly, etc.

[0003] In the prior art, a hardware-based fuel injector sticking protection is adopted. Figure 1 As shown in the figure, when the fuel injection amount is too large or the fuel injection time is too long, the pressure in the accumulator chamber drops sharply, the inlet pressure of the fuel injector is greater than the pressure in the accumulator chamber, which pushes the ball against the spring pressure to move down to the ball seat and cut off the fuel supply of the fuel injector, thereby protecting the diesel engine.

[0004] However, this structure can only protect the diesel engine when the fuel injector is stuck at the "open" position, and cannot protect the diesel engine when the fuel injector is stuck at the "closed" position. Secondly, if the fuel injector is cut off due to a large fuel injection amount, it cannot reset itself and needs to be depressurized at the fuel supply end of the fuel injector to reset. Moreover, under transient conditions such as sudden load increase of the diesel engine, the pressure in the accumulator chamber changes rapidly due to rapid changes in fuel injection amount, causing the ball to abnormally seat and the injection to abnormally close. At this time, the diesel engine cannot detect the fault and cannot reset itself to self-heal, causing trouble to the user. SUMMARY

[0005] Therefore, the present application provides a fuel injector fault diagnosis method and device based on rail pressure, a storage medium and a processor to solve the problem that the hardware-based fuel injector sticking protection in the prior art can only protect the diesel engine when the fuel injector is stuck at the "open" position, and cannot protect the diesel engine when the fuel injector is stuck at the "closed" position. Secondly, if the fuel injector is cut off due to a large fuel injection amount, it cannot reset itself and needs to be depressurized at the fuel supply end of the fuel injector to reset. Moreover, under transient conditions such as sudden load increase of the diesel engine, the pressure in the accumulator chamber changes rapidly due to rapid changes in fuel injection amount, causing the ball to abnormally seat and the injection to abnormally close. At this time, the diesel engine cannot detect the fault and cannot reset itself to self-heal, causing trouble to the user. The specific scheme is as follows:

[0006] A fuel injector fault diagnosis method based on rail pressure, comprising:

[0007] collecting real-time rail pressure data and injection quantity of each injector of a current diesel engine in a working cycle;

[0008] obtaining cylinder number of the current diesel engine, and calculating a rail pressure change coefficient of the current injector based on the cylinder number, the real-time rail pressure data and the injection quantity;

[0009] comparing the rail pressure change coefficient with a preset rail pressure change threshold;

[0010] determining that the current injector has a fault in a case where the rail pressure change coefficient is greater than the preset rail pressure change threshold.

[0011] The rail pressure-based injector fault diagnosis method described above, optionally, calculates a rail pressure change coefficient of the current injector based on the cylinder number, the real-time rail pressure data and the injection quantity, and includes:

[0012] calculating a rail pressure drop coefficient based on the cylinder number, the injection quantity and the real-time rail pressure data;

[0013] calculating a rail pressure rise coefficient based on the cylinder number and the real-time rail pressure data;

[0014] respectively calculating absolute values of differences between the rail pressure drop coefficient and the rail pressure rise coefficient and 1 to obtain a first coefficient and a second coefficient, and selecting a maximum value of the first coefficient and the second coefficient as the rail pressure change coefficient.

[0015] The rail pressure-based injector fault diagnosis method described above, optionally, calculates a rail pressure drop coefficient based on the cylinder number, the injection quantity and the real-time rail pressure data, and includes:

[0016] obtaining target rail pressure data and target injection quantity of the current injector, wherein the target rail pressure data includes a first common rail pressure at an opening time of the current injector, a second common rail pressure at a closing time of the current injector and a third common rail pressure at a closing delay of the current injector;

[0017] calculating a pressure difference value of the first common rail pressure and the second common rail pressure, and taking a ratio of the pressure difference value to the target injection quantity as a first parameter;

[0018] for each injector, calculating a ratio of a difference value between a common rail pressure at an opening time of the injector and a common rail pressure at a closing time of the injector to injection quantity of the injector based on the real-time rail pressure data and the injection quantity, obtaining each second parameter, and taking a ratio of a sum of the each second parameter to the cylinder number as a third parameter;

[0019] The ratio of the first parameter to the third parameter is used as the rail pressure reduction coefficient.

[0020] The above-mentioned injector fault diagnosis method based on rail pressure may optionally include calculating the rail pressure rise coefficient based on the number of cylinders and the real-time rail pressure data, including:

[0021] Calculate the first pressure difference between the third common rail pressure and the second common rail pressure;

[0022] For each injector, based on the real-time rail pressure data, calculate each second pressure difference between the common rail pressure after the shut-off delay and the common rail pressure at the shut-off moment of the injector, and use the ratio of each second difference to the number of cylinders as the third pressure difference.

[0023] The ratio of the first pressure difference to the third pressure difference is used as the rail pressure drop increase coefficient.

[0024] The above-mentioned injector fault diagnosis method based on rail pressure may optionally include:

[0025] The number of times the rail pressure change coefficient is continuously greater than the preset rail pressure change threshold is counted;

[0026] If the number of occurrences exceeds a preset threshold, an active oil control operation will be performed.

[0027] The above-mentioned injector fault diagnosis method based on rail pressure may optionally further include: determining that the current injector has a fault when the rail pressure change coefficient is greater than the preset rail pressure change threshold, including:

[0028] If the first coefficient is the rail pressure change coefficient, it is determined that the current injector has a normally open fault.

[0029] If the second coefficient is the rail pressure change coefficient, it is determined that the current injector has a normally closed fault.

[0030] A rail pressure-based injector fault diagnosis device includes:

[0031] The data acquisition module is used to collect real-time rail pressure data and fuel injection quantity of each injector in a current diesel engine working cycle;

[0032] The acquisition and calculation module is used to acquire the number of cylinders of the current diesel engine, and for the current injector, calculate the rail pressure change coefficient of the current injector based on the number of cylinders, the real-time rail pressure data and the injection quantity;

[0033] The comparison module is used to compare the rail pressure change coefficient with a preset rail pressure change threshold.

[0034] A determination module is configured to determine that the current fuel injector has a fault when the rail pressure variation coefficient is greater than the preset rail pressure variation threshold.

[0035] The rail pressure-based fuel injector fault diagnosis device can further include:

[0036] A first calculation unit is configured to calculate a rail pressure reduction coefficient based on the number of cylinders, the fuel injection amount, and the real-time rail pressure data.

[0037] A second calculation unit is configured to calculate a rail pressure increase coefficient based on the number of cylinders and the real-time rail pressure data.

[0038] A calculation and selection unit is configured to calculate absolute values of differences between the rail pressure reduction coefficient and the rail pressure increase coefficient and 1 respectively, to obtain a first coefficient and a second coefficient, and to select a maximum value of the first coefficient and the second coefficient as a rail pressure variation coefficient.

[0039] The rail pressure-based fuel injector fault diagnosis device can further include:

[0040] An acquisition subunit is configured to acquire target rail pressure data and a target fuel injection amount of the current fuel injector, wherein the target rail pressure data includes a first common rail pressure at a time when the current fuel injector is opened, a second common rail pressure at a time when the current fuel injector is closed, and a third common rail pressure after a delay when the current fuel injector is closed.

[0041] A first calculation subunit is configured to calculate a pressure difference between the first common rail pressure and the second common rail pressure, and to take a ratio of the pressure difference to the target fuel injection amount as a first parameter.

[0042] A second calculation subunit is configured to calculate, for each fuel injector, a ratio of a difference between a common rail pressure at a time when the fuel injector is opened and a common rail pressure at a time when the fuel injector is closed to a corresponding fuel injection amount based on the real-time rail pressure data and the fuel injection amount, to obtain each second parameter, and to take a ratio of a sum of the each second parameter to the number of cylinders as a third parameter.

[0043] A first determination subunit is configured to take a ratio of the first parameter to the third parameter as a rail pressure reduction coefficient.

[0044] The rail pressure-based fuel injector fault diagnosis device can further include:

[0045] A third calculation subunit is configured to calculate a first pressure difference between the third common rail pressure and the second common rail pressure.

[0046] A fourth calculation sub-unit is configured to calculate, for each fuel injector, a respective second pressure difference between the common rail pressure when the fuel injector passes through the closing delay and the common rail pressure at the time when the fuel injector is closed based on the real-time common rail pressure data, and take the ratio of the respective second difference to the number of cylinders as a third pressure difference;

[0047] A second determination sub-unit is configured to take the ratio of the first pressure difference to the third pressure difference as a common rail pressure drop increase coefficient.

[0048] A storage medium comprising a stored program, wherein the program performs the rail pressure-based fuel injector fault diagnosis method described above.

[0049] A processor configured to run a program, wherein the program performs the rail pressure-based fuel injector fault diagnosis method described above when running.

[0050] Compared with the prior art, the present application has the following advantages:

[0051] The present application discloses a rail pressure-based fuel injector fault diagnosis method, device, storage medium and processor, comprising: collecting real-time common rail pressure data and fuel injection amount of each fuel injector in a working cycle of a current diesel engine; obtaining the number of cylinders of the current diesel engine, calculating the common rail pressure change coefficient of the current fuel injector based on the number of cylinders, real-time common rail pressure data and fuel injection amount for the current fuel injector; comparing the common rail pressure change coefficient with a preset common rail pressure change threshold value, and determining that the current fuel injector has a fault if the common rail pressure change coefficient is greater than the preset common rail pressure change threshold value. The above process determines whether the fuel injector has a fault based on the common rail pressure change coefficient, avoiding the problem that in the prior art, the fuel injector stuck protection device using hardware cannot protect when the fuel injector is stuck in the "closed" position, the fuel injector is cut off due to large fuel injection amount, cannot reset itself, and the fuel injection amount changes rapidly, which causes the pressure in the accumulator chamber to change rapidly, causing the small ball to abnormally seat and the injection to abnormally close. BRIEF DESCRIPTION OF DRAWINGS

[0052] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed in the embodiments or prior art description will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0053] Figure 1 A schematic diagram of a hardware fuel injector stuck protection device in the prior art;

[0054] Figure 2 A flowchart of a rail pressure-based fuel injector fault diagnosis method disclosed in an embodiment of the present application;

[0055] Figure 3 A schematic diagram of a real-time rail pressure compaction measured value and an oil injector power-on signal is disclosed for the embodiments of the present application.

[0056] Figure 4 A schematic diagram of a single-cylinder rail pressure fluctuation is disclosed for the embodiments of the present application.

[0057] Figure 5 A structure block diagram of a rail pressure-based oil injector fault diagnosis device is disclosed for the embodiments of the present application.

[0058] Figure 6 A structure schematic diagram of a device is disclosed for the embodiments of the present application. DETAILED DESCRIPTION

[0059] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative efforts fall within the protection scope of the present application.

[0060] The present application discloses a rail pressure-based oil injector fault diagnosis method and device, storage medium and processor, which are applied to judging the oil injector fault according to the rail pressure change of a high-pressure common rail diesel engine, triggering protection measures such as alarm parking, so as to realize the protection of the diesel engine. The rail pressure refers to the pressure on the common oil supply pipe in the high-pressure common rail system. The high-pressure common rail refers to that the high-pressure oil pump delivers diesel oil to the common oil supply pipe, and each cylinder oil injector is connected with the common oil supply pipe. Through the control of the oil pressure in the common oil pipe and the opening and closing of each cylinder oil injector, the generation of "injection pressure" and the "injection action" of each cylinder are realized, which is a diesel oil supply mode completely separated from each other.

[0061] In the embodiments of the present application, in order to solve the problem that the hardware-based oil injector sticking protection in the prior art can only realize the protection of the diesel engine when the oil injector sticks at the "open" position, and cannot realize the protection when the oil injector sticks at the "closed" position, and further, if the oil injection amount is large, the oil injector cannot be reset by itself, and the oil supply end of the oil injector needs to be depressurized to reset, and in addition, under transient conditions such as sudden load increase of the diesel engine, due to the rapid change of the oil injection amount, the pressure in the pressure accumulation cavity changes rapidly, which causes abnormal seating of the small ball and abnormal closing of the injection, at this time, the diesel engine cannot detect the fault and cannot reset and self-recover by itself, which causes the problem of disturbing the user, a rail pressure-based oil injector fault diagnosis method is proposed, the execution process of the method is as shown in Figure 2

[0062] ​S101, collect real-time rail pressure data and injection quantity of each injector of the current diesel engine in a working cycle;

[0063] In the embodiment of the present application, the current diesel engine contains a fixed number of cylinders, each cylinder corresponds to an injector, and one working cycle is completed by four processes of intake, compression, combustion expansion and exhaust. The real-time rail pressure data can be obtained based on a pressure sensor, and the injection quantity can be obtained based on a flow sensor. In the embodiment of the present application, the collection method of the rail pressure data and the injection quantity is not limited.

[0064] S102, obtain the number of cylinders of the current diesel engine, and calculate the rail pressure variation coefficient of the current injector based on the number of cylinders, the real-time rail pressure data and the injection quantity;

[0065] In the embodiment of the present application, the number of cylinders of the diesel engine is a fixed value, which can be obtained at a specified position. In the embodiment of the present application, the specific acquisition method is not limited.

[0066] First, the rail pressure reduction coefficient is calculated based on the number of cylinders, the injection quantity and the real-time rail pressure data. The specific calculation process is as follows:

[0067] Obtain the target rail pressure data and the target injection quantity of the current rail pressure device, wherein the target rail pressure data includes: the first common rail pressure at the opening time of the current injector, the second common rail pressure at the closing time of the current injector and the third common rail pressure after the closing delay of the current injector. The closing delay of the injector refers to the time from the closing of the injector drive signal (power-on time) to the time when the injector needle falls and the injection is terminated. Because of the physical action delay and the drive signal, the injector has a closing delay time, which is usually only related to the hardware of the injector and is a fixed value. The target rail pressure data is obtained based on the real-time rail pressure data, and the target injection quantity is known.

[0068] In the embodiment of the present application, there is a certain relationship between the real-time rail pressure measurement value and the injector power-on signal. The rail (common rail pipe) is a whole, and all the injectors of the cylinders are installed on the rail (common rail pipe). The injector is powered on by the ECU to drive opening and closing. When the injector is opened, the rail pressure will continuously decrease. When the injector is closed, the rail pressure will continuously increase. After the "injector closing time + injector closing delay time", the rail pressure reaches a high level. The real-time rail pressure measurement value and the injector power-on signal are shown in Figure 3 .

[0069] In the embodiment of the present application, if the current fuel injector is the a-th cylinder fuel injector, the real-time rail pressure measured value, the fuel injector closing delay, the fuel injector power-on signal, the first common rail pressure pa1, the second common rail pressure pa2 and the third common rail pressure pa3 under the single cylinder injection action are taken Figure 4 as shown.

[0070] Among them:

[0071] pa1: the first common rail pressure at the a-th cylinder fuel injector opening time;

[0072] pa2: the second common rail pressure at the a-th cylinder fuel injector closing time;

[0073] pa3: the third common rail pressure after the a-th cylinder fuel injector closing delay;

[0074] In the embodiment of the present application, because the rail pressure drop after injection is affected by the single injection amount before injection, the single injection rail pressure drop coefficient is calculated by considering the single cylinder cycle oil amount; and the influence of different injection amounts of each cylinder on the calculation of the rail pressure deviation coefficient in the transient process is avoided.

[0075] First, the pressure difference of the first common rail pressure pa1 and the second common rail pressure pa2 is calculated, and the ratio of the pressure difference to the target injection amount is taken as a first parameter; for each fuel injector, the difference between the common rail pressure at the fuel injector opening time and the common rail pressure at the fuel injector closing time is calculated based on the real-time rail pressure data and the injection amount, and the ratio of the injection amount corresponding to each second parameter is obtained, and the sum of the second parameters is taken as a third parameter, and the ratio of the first parameter to the third parameter is taken as a rail pressure drop coefficient, as shown in formula (1);

[0076]

[0077] Among them:

[0078] m is the number of cylinders of the diesel engine;

[0079] q a is the set injection amount of the a-th cylinder;

[0080] δ a降 is the rail pressure drop coefficient after the a-th cylinder injection.

[0081] Then, the rail pressure rise coefficient is calculated based on the number of cylinders and the real-time rail pressure data, and the specific processing process is as follows:

[0082] Since the rail pressure rise is not affected by the single cylinder oil quantity, but affected by the injector closing delay, first, a first pressure difference value between the third common rail pressure and the second common rail pressure is calculated, for each injector, a respective second pressure difference value between the common rail pressure after the injector passing the closing delay and the common rail pressure at the injector closing time is calculated based on the real-time rail pressure data, the ratio between the respective second difference value and the cylinder number is taken as a third pressure difference value, and the ratio between the first pressure difference value and the third pressure difference value is taken as a rail pressure drop rise coefficient. As shown in formula (2),

[0083]

[0084] The absolute values of the differences between the rail pressure drop coefficient and the rail pressure rise coefficient and 1 are respectively calculated to obtain a first coefficient and a second coefficient, and the maximum value between the first coefficient and the second coefficient is taken as a rail pressure change coefficient.

[0085] As shown in formula (3),

[0086]

[0087] Wherein:

[0088] δ a : the rail pressure change coefficient of the a-th cylinder;

[0089] q a : the set injection quantity of the a-th cylinder;

[0090] m: the cylinder number of the current engine;

[0091] In the embodiment of the present application, for the rail pressure rise coefficient and the rail pressure drop coefficient, when the injector is stuck in the normally open position, the rail pressure rise coefficient is more sensitive, when the injector is stuck in the normally closed position, the rail pressure drop coefficient is more sensitive. Under normal working conditions, the rail pressure drop coefficient / rail pressure rise coefficient should be equal to 1, when an abnormality occurs, the coefficient will be much greater than 1 or much less than 1, here, 1 is subtracted, the absolute value is taken, and finally the maximum value is taken, in order to find out how much the rail pressure coefficient is different from 1. The closer to 1, the more normal the system runs.

[0092] S103, comparing the rail pressure change coefficient with a preset rail pressure change threshold value;

[0093] In the embodiment of the present application, the rail pressure change coefficient is compared with the preset rail pressure change threshold value, wherein the preset rail pressure change threshold value can be set based on experience or specific circumstances, and the specific value of the preset rail pressure change threshold value is not limited in the embodiment of the present application, preferably, the preset rail pressure change threshold value in the embodiment of the present application is 0.25. That is, the rail pressure change coefficient exceeding 0.25 represents an abnormality.

[0094] S104, in the case where the rail pressure variation coefficient is greater than the preset rail pressure variation threshold, it is determined that the current fuel injector has a fault.

[0095] In the embodiment of the present application, in the case where the rail pressure variation coefficient is greater than the preset rail pressure variation threshold, it is determined that the current fuel injector has a fault, otherwise, it is determined that the current fuel injector is running normally.

[0096] Further, on the premise that the current fuel injector has a fault, the rail pressure variation coefficient is obtained, if the first coefficient is the rail pressure variation coefficient, it is determined that the current fuel injector has a normally open fault; if the second coefficient is the rail pressure variation coefficient, it is determined that the current fuel injector has a normally closed fault.

[0097] Further, on the premise that the current fuel injector has a fault, the number of times that the condition that the rail pressure variation coefficient is greater than the preset rail pressure variation threshold continuously appears is counted, and in the case where the number of times is greater than a preset number of times threshold, active oil control operation is performed, wherein the active oil control operation includes active fuel limiting and active fuel cut-off actions, the preset number of times threshold can be set based on experience or specific conditions, which is not specifically limited in the embodiment of the present application, preferably, in the embodiment of the present application, active fuel limiting, fuel cut-off and the like are performed when the rail pressure variation coefficient is continuously determined to be abnormal for 4-8 working cycles.

[0098] The present application discloses a kind of based on rail pressure's fuel injector fault diagnosis method, comprising: collecting the real-time rail pressure data and injection quantity of each fuel injector of current diesel engine in a working cycle;Obtain the cylinder number of current diesel engine, based on cylinder number, real-time rail pressure data and injection quantity, the rail pressure variation coefficient of current fuel injector is calculated for current fuel injector;Rail pressure variation coefficient is compared with preset rail pressure variation threshold, in the case where rail pressure variation coefficient is greater than preset rail pressure variation threshold, it is determined that current fuel injector has a fault.The above process, based on rail pressure variation coefficient determines whether fuel injector has a fault, avoid the problem that when being stuck in " closed " position by using the fuel injector stuck protection of hardware, cannot realize protection, because injection quantity is large, leading to fuel injector cut-off, cannot reset and injection quantity change is fast, it can lead to the pressure of pressure accumulation cavity rapidly change, leading to small ball abnormal seat, injection abnormal closing problem.

[0099] Based on the above-mentioned one kind based on rail pressure's fuel injector fault diagnosis method, in the embodiment of the present application, a kind of based on rail pressure's fuel injector fault diagnosis device is provided, as shown in the structure block diagram of the device Figure 5 Including:

[0100] Acquisition module 201, acquisition and calculation module 202, comparison module 203 and determination module 204.

[0101] in,

[0102] The acquisition module 201 is used to acquire real-time rail pressure data and fuel injection quantity of each injector of the current diesel engine in one working cycle.

[0103] The acquisition and calculation module 202 is used to acquire the number of cylinders of the current diesel engine, and for the current injector, calculate the rail pressure change coefficient of the current injector based on the number of cylinders, the real-time rail pressure data and the injection quantity.

[0104] The comparison module 203 is used to compare the rail pressure change coefficient with a preset rail pressure change threshold.

[0105] The determination module 204 is used to determine that the current injector is faulty when the rail pressure change coefficient is greater than the preset rail pressure change threshold.

[0106] This invention discloses a fuel injector fault diagnosis device based on rail pressure, comprising: collecting real-time rail pressure data and injection quantity of each injector in a current diesel engine working cycle; obtaining the number of cylinders in the current diesel engine; calculating the rail pressure variation coefficient of the current injector based on the number of cylinders, real-time rail pressure data, and injection quantity; comparing the rail pressure variation coefficient with a preset rail pressure variation threshold; and determining that the current injector is faulty if the rail pressure variation coefficient is greater than the preset rail pressure variation threshold. This process, based on the rail pressure variation coefficient, determines whether the injector is faulty, avoiding the problems of hardware-based injector jamming protection failing to protect when stuck in the "closed" position, large injection quantities causing injector cut-off and inability to self-reset, and rapid changes in injection quantity leading to rapid pressure changes in the accumulator chamber, resulting in abnormal ball seating and abnormal injection shut-off.

[0107] In this embodiment of the invention, the acquisition and calculation module 204 includes:

[0108] The system comprises a first calculation unit, a second calculation unit, and a calculation and selection unit.

[0109] in,

[0110] The first calculation unit is used to calculate the rail pressure reduction coefficient based on the number of cylinders, the injection quantity, and the real-time rail pressure data;

[0111] The second calculation unit is used to calculate the rail pressure rise coefficient based on the number of cylinders and the real-time rail pressure data;

[0112] The calculation and selection unit is used to calculate the absolute values ​​of the differences between the rail pressure reduction coefficient and the rail pressure increase coefficient and 1, respectively, to obtain a first coefficient and a second coefficient, and to select the maximum value of the first coefficient and the second coefficient as the rail pressure change coefficient.

[0113] The first calculation unit comprises:

[0114] The acquisition subunit, the first calculation subunit, the second calculation subunit and the first determination subunit.

[0115] The second calculation unit comprises:

[0116] The acquisition subunit is configured to acquire target rail pressure data and a target injection amount of the current rail pressure device, wherein the target rail pressure data comprises a first common rail pressure at a current injector opening time, a second common rail pressure at a current injector closing time and a third common rail pressure at a current injector closing delay time.

[0117] The first calculation subunit is configured to calculate a pressure difference value of the first common rail pressure and the second common rail pressure, and take a ratio of the pressure difference value to the target injection amount as a first parameter.

[0118] The second calculation subunit is configured to calculate, for each injector, a ratio of a difference value between a common rail pressure at an injector opening time and a common rail pressure at an injector closing time to a corresponding injection amount based on the real-time rail pressure data and the injection amount, to obtain each second parameter, and take a ratio of a sum of the each second parameter to the cylinder number as a third parameter.

[0119] The first determination subunit is configured to take a ratio of the first parameter to the third parameter as a rail pressure reduction coefficient.

[0120] The second calculation unit comprises:

[0121] The third calculation subunit, the fourth calculation subunit and the second determination subunit.

[0122] The second calculation unit comprises:

[0123] The third calculation subunit is configured to calculate a first pressure difference value of the third common rail pressure and the second common rail pressure.

[0124] The fourth calculation subunit is configured to calculate, for each injector, each second pressure difference value of a common rail pressure at an injector closing delay time and a common rail pressure at an injector closing time based on the real-time rail pressure data, and take a ratio of the each second difference value to the cylinder number as a third pressure difference value.

[0125] The second determination subunit is configured to take a ratio of the first pressure difference value to the third pressure difference value as a rail pressure reduction increase coefficient.

[0126] The distribution device comprises a processor and a memory, the acquisition module, the acquisition and calculation module, the comparison module and the determination module are all stored in the memory as program units, and the corresponding functions are realized by the processor executing the program units stored in the memory.

[0127] The processor comprises a core, and the core calls the corresponding program units in the memory. The core can be set to one or more, and by adjusting the core parameters, the problem that the protection cannot be realized when the fuel injector is stuck in the "off position due to the fuel injector cut-off caused by the large fuel injection amount, the self-resetting cannot be realized, and the fuel injection amount changes rapidly, the pressure of the accumulator chamber changes rapidly, the small ball is abnormally seated, and the injection is abnormally closed can be avoided.

[0128] The memory can comprise a non-permanent memory in a computer readable medium, a random access memory (RAM) and / or a non-volatile memory such as a read-only memory (ROM) or a flash memory (flash RAM), and the memory comprises at least one memory chip.

[0129] The embodiment of the present application provides a computer storage medium, which stores a program, and the program is executed by a processor to realize the rail pressure-based fuel injector fault diagnosis method.

[0130] The embodiment of the present application provides a processor, which is used for running a program, and the program is executed to realize the rail pressure-based fuel injector fault diagnosis method.

[0131] The embodiment of the present application provides a device, and a structural block diagram of the device is as shown in Figure 6 The device comprises a processor 301, a storage medium 302, and a program stored in the storage medium 302 and capable of running on the processor 302, and the processor 301 realizes the following steps when executing the program.

[0132] Acquiring real-time rail pressure data and fuel injection amount of each fuel injector of a current diesel engine in one working cycle;

[0133] Acquiring the number of cylinders of the current diesel engine, and calculating a rail pressure change coefficient of the current fuel injector based on the number of cylinders, the real-time rail pressure data and the fuel injection amount;

[0134] Comparing the rail pressure change coefficient with a preset rail pressure change threshold value;

[0135] In the case that the rail pressure change coefficient is greater than the preset rail pressure change threshold value, it is determined that the current fuel injector has a fault.

[0136] Those skilled in the art will appreciate that embodiments of the application can be readily used as software, hardware, or a combination of software and hardware. In a typical configuration, a computing device includes one or more processors (CPUs), input / output interfaces, network interfaces, and memory.

[0137] The computer program instructions can also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart block or blocks. Figure 1 one or more flow or blocks Figure 1 means for functionally implementing the steps listed in the flowchart block or blocks.

[0138] These computer program instructions can also be stored in a computer readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer readable memory produce an article of manufacture including instructions which implement the function specified in the flowchart block or blocks. Figure 1 one or more flow or blocks Figure 1 means for functionally implementing the steps listed in the flowchart block or blocks.

[0139] The computer program instructions can also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart block or blocks. Figure 1 one or more flow or blocks Figure 1 means for functionally implementing the steps listed in the flowchart block or blocks.

[0140] In one typical configuration, the computing device includes one or more processors (CPUs), input / output interfaces, network interfaces, and memory.

[0141] The memory can include non-persistent memory and / or persistent memory, such as flash memory, read-only memory (ROM), and / or volatile or non-volatile random access memory (RAM), among others. The memory is an example of computer readable media.

[0142] Computer-readable media includes permanent and non-permanent, movable and non-movable media that can be implemented by any method or technology to store information. The information can be computer-readable instructions, data structures, program modules or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, compact disc read-only memory (CD-ROM), digital versatile disc (DVD) or other optical storage, magnetic cassette, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other non-transmission medium that can be used to store information accessible to a computing device. According to the definition herein, computer-readable media does not include transitory media such as modulated data signals and carriers.

[0143] It should also be noted that the terms "comprising", "containing", or any other variant thereof are intended to cover non-exclusive inclusions, such that a process, method, article or apparatus that comprises a list of elements does not only include those elements, but also other elements not explicitly listed or inherent to such a process, method, article or apparatus. Without more limitations, the element defined by the statement "comprising a" does not exclude the presence of additional identical elements in the process, method, article or apparatus that includes the element.

[0144] Those skilled in the art will appreciate that embodiments of the present application can be provided as a method, system or computer program product. Accordingly, the present application can take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present application can take the form of a computer program product implemented on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROMs, optical storage devices, etc.) containing computer usable program code.

[0145] The above merely provides embodiments of the present application and is not intended to limit the present application. Various modifications and changes can be made to the present application by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included in the scope of the claims of the present application.

Claims

1. A method for diagnosing injector faults based on rail pressure, characterized in that, include: Collect real-time rail pressure data and fuel injection quantity of each injector in a current diesel engine working cycle; The number of cylinders of the current diesel engine is obtained. For the current injector, the target rail pressure data and target injection quantity of the current injector are obtained. The target rail pressure data includes: the first common rail pressure at the time the current injector is opened, the second common rail pressure at the time the current injector is closed, and the third common rail pressure of the current injector after the closing delay. Calculate the pressure difference between the first common rail pressure and the second common rail pressure, and use the ratio of the pressure difference to the target fuel injection quantity as the first parameter; For each injector, based on the real-time rail pressure data and the injection quantity, the ratio of the difference between the common rail pressure at the injector opening time and the common rail pressure at the injector closing time to the corresponding injection quantity is calculated to obtain each second parameter. The ratio of the sum of each second parameter to the number of cylinders is used as the third parameter. The ratio of the first parameter to the third parameter is used as the rail pressure reduction coefficient; Calculate the first pressure difference between the third common rail pressure and the second common rail pressure; For each injector, based on the real-time rail pressure data, calculate each second pressure difference between the common rail pressure after the shut-off delay and the common rail pressure at the shut-off moment of the injector, and use the ratio of each second pressure difference to the number of cylinders as the third pressure difference. The ratio of the first pressure difference to the third pressure difference is used as the rail pressure rise coefficient; Calculate the absolute values ​​of the differences between the rail pressure reduction coefficient and the rail pressure increase coefficient and 1 respectively to obtain the first coefficient and the second coefficient. Select the maximum value of the first coefficient and the second coefficient as the rail pressure change coefficient. The rail pressure variation coefficient is compared with a preset rail pressure variation threshold. If the rail pressure change coefficient is greater than the preset rail pressure change threshold, the current injector is determined to be faulty.

2. The injector fault diagnosis method based on rail pressure according to claim 1, characterized in that, Also includes: The number of times the rail pressure change coefficient is continuously greater than the preset rail pressure change threshold is counted; If the number of occurrences exceeds a preset threshold, an active oil control operation will be performed.

3. The injector fault diagnosis method based on rail pressure according to claim 1, characterized in that, Also includes: If the rail pressure variation coefficient is greater than the preset rail pressure variation threshold, it is determined that the current injector is faulty, including: If the first coefficient is the rail pressure change coefficient, it is determined that the current injector has a normally open fault. If the second coefficient is the rail pressure change coefficient, it is determined that the current injector has a normally closed fault.

4. A fuel injector fault diagnosis device based on rail pressure, characterized in that, include: The data acquisition module is used to collect real-time rail pressure data and fuel injection quantity of each injector in a current diesel engine working cycle; The acquisition and calculation module is used to acquire the number of cylinders of the current diesel engine, and for the current injector, calculate the rail pressure change coefficient of the current injector based on the number of cylinders, the real-time rail pressure data and the injection quantity; The comparison module is used to compare the rail pressure change coefficient with a preset rail pressure change threshold. The determination module is used to determine that the current injector is faulty when the rail pressure change coefficient is greater than the preset rail pressure change threshold. The acquisition and calculation module includes: The first calculation unit is used to calculate the rail pressure reduction coefficient based on the number of cylinders, the amount of fuel injection, and the real-time rail pressure data. The second calculation unit is used to calculate the rail pressure rise coefficient based on the number of cylinders and the real-time rail pressure data; The calculation and selection unit is used to calculate the absolute values ​​of the differences between the rail pressure reduction coefficient and the rail pressure increase coefficient and 1, respectively, to obtain a first coefficient and a second coefficient, and to select the maximum value of the first coefficient and the second coefficient as the rail pressure change coefficient. The first computing unit includes: The acquisition subunit is used to acquire the target rail pressure data and target injection quantity of the current injector, wherein the target rail pressure data includes: the first common rail pressure at the time the current injector is opened, the second common rail pressure at the time the current injector is closed, and the third common rail pressure of the current injector after the closing delay; The first calculation subunit is used to calculate the pressure difference between the first common rail pressure and the second common rail pressure, and to use the ratio of the pressure difference to the target fuel injection quantity as the first parameter. The second calculation subunit is used to calculate, for each injector, the ratio of the difference between the common rail pressure at the time the injector opens and the common rail pressure at the time the injector closes, and the corresponding injection quantity, based on the real-time rail pressure data and the injection quantity, to obtain each second parameter, and the ratio of the sum of each second parameter to the number of cylinders is used as the third parameter. The first determining subunit is used to use the ratio of the first parameter to the third parameter as the rail pressure reduction coefficient. The second computing unit includes: The third calculation subunit is used to calculate the first pressure difference between the third common rail pressure and the second common rail pressure. The fourth calculation subunit is used to calculate, for each injector, the second pressure difference between the common rail pressure after the shut-off delay and the common rail pressure at the shut-off moment of the injector based on the real-time rail pressure data, and to use the ratio of each second pressure difference to the number of cylinders as the third pressure difference. The second determining subunit is used to take the ratio of the first pressure difference to the third pressure difference as the rail pressure rise coefficient.

5. A storage medium, characterized in that, The storage medium includes a stored program, wherein the program executes the injector fault diagnosis method based on rail pressure as described in any one of claims 1-3.

6. A processor, characterized in that, The processor is used to run a program, wherein the program executes the injector fault diagnosis method based on rail pressure as described in any one of claims 1-3.

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