Method and device for adjusting injection parameters of a gaseous fuel direct injection internal combustion engine

Abstract

The application relates to the technical field of internal combustion engines, in particular to a gas fuel direct injection internal combustion engine injection parameter adjusting method and device. The method obtains the fuel inlet rail pressure, inlet gas rail temperature, engine speed, engine load and target fuel injection mass of the current internal combustion engine; calculates the injection window of the current internal combustion engine according to the fuel inlet rail pressure, inlet gas rail temperature, engine speed, engine load and target fuel injection mass; compares the injection window of the current internal combustion engine with the ignition advance angle and intake valve closing angle of the internal combustion engine, and adjusts the injection parameter of the internal combustion engine according to the comparison result, so that the injection window of the internal combustion engine is in a safe range, thereby improving the safety of the injection system of the internal combustion engine.

Description

Technical Field

[0001] This application relates to the field of internal combustion engine technology, specifically to a method and device for adjusting injection parameters of a gas fuel direct injection internal combustion engine. Background Technology

[0002] The hydrogen injection system is an important component of the hydrogen internal combustion engine. Its main function is to provide hydrogen to the hydrogen internal combustion engine on demand for combustion and power output to the power system.

[0003] High-pressure gaseous hydrogen from the high-pressure hydrogen cylinder enters the gas rail through a pressure reducing valve and an electronically controlled pressure regulating valve, and then supplies hydrogen to the internal combustion engine through a hydrogen nozzle.

[0004] Hydrogen injection methods are mainly divided into two types: intake port injection and direct injection into the cylinder.

[0005] The injection pulse width of the port-injected hydrogen engine is relatively large and the window time is long. Because the hydrogen is mixed with the incoming fresh air in the intake manifold or intake passage in advance, the mixture is then ignited and burned in the cylinder. However, since hydrogen also occupies a part of the volume during the intake process, it reduces the actual charging efficiency of the internal combustion engine. Therefore, the torque of the port-injected hydrogen engine is limited.

[0006] The main advantage of in-cylinder hydrogen direct injection nozzles is that they inject hydrogen after the intake valve is closed, without taking up extra cylinder volume during the intake process, thus significantly improving intake efficiency. Furthermore, in-cylinder injection occurs during the compression stroke after the intake is closed, effectively avoiding the possibility of backfire.

[0007] However, in a direct hydrogen injection system, due to the small injection window, which is limited to the compression stroke, the injection pulse width increases as engine speed increases, rail pressure decreases, and the target injection flow rate increases. When the injection end angle approaches the engine's top dead center, the hydrogen and air do not mix sufficiently, resulting in a decrease in the engine's actual torque. In severe cases, it can also cause some unburned hydrogen to undergo afterburning in the exhaust pipe, damaging the engine's exhaust system. Summary of the Invention

[0008] In view of the shortcomings of the prior art described above, the purpose of this application is to provide a method and device for adjusting the injection parameters of a gas fuel direct injection internal combustion engine, in order to improve the safety of the hydrogen direct injection internal combustion engine injection system.

[0009] To achieve the above and other related objectives, this application provides a method for adjusting injection parameters of a gaseous fuel direct injection internal combustion engine, the method comprising:

[0010] The injection window of the current internal combustion engine is calculated by obtaining the current fuel inlet rail pressure, inlet rail temperature, engine speed, engine load, and target fuel injection mass.

[0011] The current injection window of the internal combustion engine is compared with the ignition advance angle and intake valve closing angle of the internal combustion engine, and the injection parameters of the internal combustion engine are adjusted according to the comparison results so that the injection window of the internal combustion engine is within a safe range.

[0012] In an optional embodiment of this application, the injection window of the current internal combustion engine is calculated based on the fuel inlet rail pressure, inlet rail temperature, engine speed, and target fuel injection mass, including:

[0013] Based on the engine speed and engine load, the corresponding first injection initiation angle is matched by querying a preset angle table.

[0014] The first fuel injection pulse width is calculated and generated based on the target fuel injection mass, fuel inlet rail pressure, and inlet gas rail temperature.

[0015] The injection end angle is calculated and generated based on the first fuel injection pulse width, engine speed, and the injection start angle.

[0016] The injection window of the current internal combustion engine is generated based on the injection start angle and the injection end angle.

[0017] In an optional embodiment of this application, the first fuel injection pulse width is calculated and generated based on the target fuel injection mass, fuel inlet rail pressure and inlet air rail temperature, including: obtaining the fuel inlet marked rail pressure, inlet air rail marked temperature and the nozzle mass flow rate measurement value when the fuel inlet rail pressure of the internal combustion engine is the fuel inlet marked rail pressure and the inlet air rail temperature is the inlet air rail marked temperature;

[0018] The first fuel injection pulse width is calculated based on the fuel inlet rail pressure, fuel inlet gas rail temperature, nozzle mass flow rate measurement, target fuel injection mass, fuel inlet rail pressure, and inlet gas rail temperature.

[0019] In an optional embodiment of this application, the calculation of a first fuel injection pulse width based on the target fuel injection mass, fuel inlet rail pressure, and inlet gas rail temperature includes:

[0020] The method for generating the first fuel injection pulse width is expressed by the following formula:

[0021] ;

[0022] in, The first fuel injection pulse width, For the target fuel injection mass, This is the current fuel inlet rail pressure of the internal combustion engine. This represents the current inlet rail temperature of the internal combustion engine. and q is a preset constant. stat For the fuel inlet rail pressure of the internal combustion engine to be The inlet rail temperature of an internal combustion engine is The nozzle mass flow rate measurement value at that time.

[0023] In an optional embodiment of this application, calculating and generating the injection termination angle based on the first fuel injection pulse width, engine speed, and the injection initiation angle includes:

[0024] Calculate the product of the first fuel injection pulse width and the engine speed to obtain the injection angle change value;

[0025] The difference between the change in the injection initiation angle and the injection intersection angle is used as the injection termination angle.

[0026] In an optional embodiment of this application, calculating and generating the injection termination angle based on the first fuel injection pulse width, engine speed, and the injection initiation angle includes:

[0027] The method for generating the spray termination angle is expressed by the following formula:

[0028] ;

[0029] in The spray termination angle, The injection initiation angle, EngSpd This represents the current engine speed of the internal combustion engine. This is the pulse width of the first fuel injection.

[0030] In an optional embodiment of this application, the current injection window of the internal combustion engine is compared with the ignition advance angle and intake valve closing angle of the internal combustion engine, and the injection parameters of the internal combustion engine are adjusted according to the comparison result to keep the injection window of the internal combustion engine within a safe range, including:

[0031] When the injection end angle lags behind the ignition advance angle, the injection end angle is assigned the preset latest injection end angle;

[0032] The injection start angle is recalculated based on the preset latest injection end angle, the first fuel injection pulse width, and the engine speed.

[0033] When the recalculated injection initiation angle is earlier than the intake valve closing angle, the injection initiation angle is assigned as the earliest injection initiation angle;

[0034] The target fuel inlet rail pressure is calculated and generated based on the earliest injection start angle, the preset latest injection end angle, the inlet gas rail temperature, and the target fuel injection mass.

[0035] When the target fuel inlet rail pressure is greater than or equal to the maximum permissible fuel inlet rail pressure, the fuel inlet rail pressure is adjusted to the maximum permissible fuel inlet rail pressure.

[0036] The maximum fuel injection mass is calculated based on the maximum permissible fuel inlet rail pressure and the inlet gas rail temperature.

[0037] Update the target fuel injection mass to the maximum fuel injection mass, and return to the step of calculating the current internal combustion engine injection window based on the fuel inlet rail pressure, inlet rail temperature, engine speed, engine load, and target fuel injection mass.

[0038] In an optional embodiment of this application, the method further includes terminating the internal combustion engine injection parameter adjustment process when the first injection end angle is advanced compared to the ignition advance angle.

[0039] In an optional embodiment of this application, the method further includes terminating the internal combustion engine injection parameter adjustment process when the second injection initiation angle lags behind the intake valve closing angle.

[0040] In an optional embodiment of this application, the method further includes adjusting the fuel inlet rail pressure to the target fuel inlet rail pressure when the target fuel inlet rail pressure is less than the maximum permissible fuel inlet rail pressure, and returning to the step of calculating the injection window of the current internal combustion engine based on the fuel inlet rail pressure, inlet rail temperature, engine speed, engine load, and target fuel injection mass.

[0041] In an optional embodiment of this application, the target fuel inlet rail pressure is calculated and generated based on the earliest injection start angle, the preset latest injection end angle, the inlet gas rail temperature, and the target fuel injection mass, including:

[0042] The second fuel injection pulse width is calculated and generated based on the earliest injection start angle, the preset latest injection end angle, and the engine speed.

[0043] The target fuel inlet rail pressure is calculated based on the second fuel injection pulse width, the inlet rail temperature, and the target fuel injection mass.

[0044] To achieve the above and other related objectives, this application also provides a gas fuel direct injection internal combustion engine injection parameter adjustment device, wherein the internal combustion engine injection parameter adjustment system includes:

[0045] The information acquisition module is used to acquire the current fuel inlet rail pressure, inlet rail temperature, engine speed, and engine load of the internal combustion engine.

[0046] The data calculation module is used to calculate the injection window of the current internal combustion engine based on the fuel inlet rail pressure, inlet gas rail temperature, engine speed, engine load and target fuel injection mass;

[0047] The data comparison and adjustment module is used to compare the current injection window of the internal combustion engine with the ignition advance angle and intake valve closing angle of the internal combustion engine, and adjust the injection parameters of the internal combustion engine according to the comparison results so that the injection window of the internal combustion engine is within a safe range.

[0048] In summary, this application includes at least one beneficial effect:

[0049] This application obtains the current internal combustion engine's fuel inlet rail pressure, inlet rail temperature, engine speed, engine load, and target fuel injection mass; calculates the current internal combustion engine's injection window based on the fuel inlet rail pressure, inlet rail temperature, engine speed, engine load, and target fuel injection mass; compares the current internal combustion engine's injection window with the engine's ignition advance angle and intake valve closing angle, and adjusts the engine's injection parameters based on the comparison results to ensure the injection window is within a safe range, thereby improving the safety of the internal combustion engine's injection system. Attached Figure Description

[0050] Figure 1 This is a schematic diagram of the structure of a hydrogen internal combustion engine electronic control system provided in the embodiments of this application.

[0051] Figure 2 This is a flowchart illustrating a method for adjusting injection parameters in a gas fuel direct injection internal combustion engine, as provided in an embodiment of this application.

[0052] Figure 3 This is a schematic diagram of a process for generating an internal combustion engine injection window, provided in an embodiment of this application.

[0053] Figure 4 This is a schematic diagram of the phase sequence of an internal combustion engine during one working cycle in an embodiment of this application.

[0054] Figure 5 This is a block diagram of a gas fuel direct injection internal combustion engine injection parameter adjustment device provided in the embodiments of this application. Detailed Implementation

[0055] The following specific examples illustrate the implementation of this application. Those skilled in the art can easily understand other advantages and effects of this application from the content disclosed in this specification. This application can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this application.

[0056] Throughout this description, numerous specific details, such as examples of components and / or methods, are provided to provide a complete understanding of embodiments of this application. However, those skilled in the art will recognize that embodiments of this application may be practiced without one or more of these specific details or by other devices, systems, components, methods, parts, materials, components, etc.

[0057] like Figure 1 As shown, this application provides an electronic control system for a hydrogen direct injection internal combustion engine, used to assist the operation of the hydrogen direct injection internal combustion engine. The core controller of the hydrogen direct injection internal combustion engine electronic control system is an ECU. The hydrogen direct injection internal combustion engine of this application needs to be matched with a hydrogen tank, which mainly stores compressed liquid hydrogen. The ECU delivers gaseous fuel to the cylinder of the internal combustion engine by controlling devices installed in the internal combustion engine, such as pressure reducing valve, regulating valve, gas rail, nozzle, and turbocharger.

[0058] This application also provides a method for adjusting injection parameters in a gas fuel direct injection internal combustion engine, wherein the main body executing this method can be the internal combustion engine ECU, and it is assisted by multiple sensors.

[0059] This application uses the parameter adjustment process of a hydrogen direct injection internal combustion engine as an example to illustrate the injection start angle, injection end angle, fuel inlet rail pressure, fuel injection pulse width, and fuel injection quality. The parameter adjustment methods for other types of gaseous fuel direct injection internal combustion engines, such as natural gas and liquefied petroleum gas, are similar and will not be described in detail.

[0060] The following will describe the specific implementation methods. Figure 2 The processing flow shown is explained in detail below:

[0061] Step S101: Obtain the current fuel inlet rail pressure, inlet rail temperature, engine speed, and engine load of the internal combustion engine.

[0062] In practice, the internal combustion engine ECU receives feedback data from multiple sensors installed on the internal combustion engine to obtain the current fuel inlet rail pressure, inlet air rail temperature, and engine speed. When the engine is running, the ECU relies on the throttle position sensor and the engine speed sensor to comprehensively determine the engine load. Engine load = actual engine intake volume * 100% / maximum engine intake volume.

[0063] Step S102 calculates the injection window of the current internal combustion engine based on the fuel inlet rail pressure, inlet rail temperature, engine speed, engine load, and target fuel injection mass.

[0064] In practice, the ECU first calculates the current fuel injection pulse width of the internal combustion engine based on the target fuel injection mass, fuel inlet rail pressure, and inlet rail temperature, and then calculates the current injection window of the internal combustion engine based on the current fuel injection pulse width.

[0065] In one specific embodiment, step S102 can also be as follows: Figure 3 The processing flow is as follows:

[0066] Step S1021: Based on the engine speed and engine load, match the corresponding injection start angle from the preset angle lookup table.

[0067] The ECU has a preset angle lookup table that records the correspondence between the internal combustion engine load and engine speed and the injection start angle. Thus, the ECU can match the corresponding injection start angle with the internal combustion engine load and engine speed as the first injection start angle.

[0068] Step S1022: Calculate and generate the first fuel injection pulse width based on the target fuel injection mass, fuel inlet rail pressure, and inlet gas rail temperature.

[0069] Specifically, the method for generating the first fuel injection pulse width is expressed by the following formula:

[0070] ;

[0071] in, The first fuel injection pulse width, For the target fuel injection mass, This is the current fuel inlet rail pressure of the internal combustion engine. This represents the current inlet rail temperature of the internal combustion engine. and q is a preset constant. stat For the fuel inlet rail pressure of the internal combustion engine to be The inlet rail temperature of an internal combustion engine is The nozzle mass flow rate measurement value at that time.

[0072] The derivation of the formula for the first fuel injection pulse width is given below:

[0073] The calculation of hydrogen direct injection flow rate is based on the adiabatic compressible flow rate equation of the gas nozzle:

[0074] ;

[0075] in, The mass flow rate of the gas. The cross-sectional area of ​​the pipeline. The pressure at the pipe inlet, For the pressure at the pipeline outlet, This refers to the temperature at the pipe inlet (Kelvin temperature). The relationship function for the pressure ratio of the adiabatic nozzle. C It is a constant;

[0076] If the inlet and outlet pressure ratio is below 0.528, the supersonic condition is met. C and The function can be simplified to a constant C2, so the above formula can be simplified to:

[0077] ;

[0078] The ECU pre-stores measured internal parameters of a hydrogen direct injection internal combustion engine, including the fuel inlet pressure rail. Temperature marked on the inlet air rail and fuel inlet rail pressure Temperature marked on the inlet air rail The measured nozzle mass flow rate is Substituting these three factors into the formula above, we can obtain the result. ;

[0079] When using fuel gas with a fixed composition, and the pressure ratio between the outlet and inlet pressures of the internal combustion engine fuel is less than or equal to 0.528, the inlet rail pressure of other fuels... and inlet air rail temperature Under the conditions described, the injection mass flow rate of a hydrogen direct injection internal combustion engine can be converted to:

[0080] ;

[0081] Among them, the current pre-stored fuel inlet rail pressure of the internal combustion engine is The current pre-stored inlet rail temperature of the internal combustion engine is The current pre-stored nozzle mass flow rate of the internal combustion engine is ;

[0082] Therefore, the target fuel injection mass is determined again. (mg) First fuel injection pulse width The formula for calculating (ms) is as follows:

[0083] ;

[0084] The 1000 in the formula represents the time unit conversion, from seconds to milliseconds.

[0085] Step S1023: Calculate the injection termination angle based on the first fuel injection pulse width, engine speed, and the injection start angle. Specifically, when calculating the injection termination angle, first calculate the product of the first fuel injection pulse width and the engine speed to obtain the injection angle change value; then calculate the difference between the injection start angle and the injection angle change value as the injection termination angle.

[0086] As an example, it can be based on the first injection pulse width t inj (ms), injection initiation angle agSOI ( º The injection termination angle (agEOI) is calculated using CA and engine speed EngSpd (rpm). º CA), calculate the injection termination angle using the following formula:

[0087] ;

[0088] in, The spray termination angle, The injection initiation angle, EngSpd This represents the current engine speed of the internal combustion engine. This is the pulse width of the first fuel injection.

[0089] Step S1024: Generate the injection window of the current internal combustion engine based on the injection start angle and the injection end angle.

[0090] like Figure 4 As shown, the ECU can obtain the injection window of the internal combustion engine in the phase sequence axis within one working cycle of the internal combustion engine by using the injection start angle and injection end angle.

[0091] in, Figure 4 The dashed line in the middle represents the intake valve opening line, with the two ends of the dashed line corresponding to the intake valve opening and intake valve closing of the internal combustion engine, respectively.

[0092] Step S103: Compare the current injection window of the internal combustion engine with the ignition advance angle and intake valve closing angle of the internal combustion engine, and adjust the injection parameters of the internal combustion engine according to the comparison results so that the injection window of the internal combustion engine is within a safe range.

[0093] In practice, during one working cycle of the internal combustion engine, the ECU compares the injection window with the ignition advance angle and the intake valve closing angle. If the injection window is located between the ignition advance angle and the intake valve closing angle, it means that the injection window of the internal combustion engine is in a safe range, and there is no need to adjust the injection parameters of the internal combustion engine. If the injection start angle in the injection window is earlier than the intake valve closing angle, or the injection end angle in the injection window is later than the ignition advance angle, then the injection parameters of the internal combustion engine need to be adjusted.

[0094] In one specific embodiment, step S103 can also be as follows: Figure 5 The processing flow is as follows:

[0095] Step S1031: Compare the injection end angle with the ignition advance angle:

[0096] When the injection end angle is advanced before the ignition advance angle, that is... ≥ + This indicates that the injection termination angle is within a safe range, meaning the internal combustion engine's injection window is within a safe range. In this case, the internal combustion engine injection parameter adjustment process ends, and the engine is controlled to inject fuel according to the current injection parameters. For the spray termination angle, agSaf( º CA) is the crankshaft angle reserved for hydrogen-air mixing, typically 10-30 degrees. º CA can be set according to different speeds. This refers to the ignition advance angle.

[0097] When the injection end angle lags behind the ignition advance angle, i.e. < + This indicates that the hydrogen injection in the internal combustion engine is too late, and the hydrogen and air do not have enough time to mix before the engine ignites. In other words, the injection end angle is not within the safe range, meaning the injection window of the internal combustion engine is not within the safe range. In this case, the injection end angle is assigned the preset latest injection end angle agEOI. latest That is, agEOI = agEOI latest =agSpk+agSaf, and jump to S1032.

[0098] Step S1032: Recalculate the injection start angle based on the preset latest injection end angle, the first fuel injection pulse width, and the engine speed.

[0099] Specifically, after the ECU adjusts the injection termination angle, the injection initiation angle can be recalculated using the following formula. .

[0100]

[0101] in, The adjusted spray termination angle, that is latest , Engine speed, This is the pulse width of the first fuel injection.

[0102] Step S1033: Compare the recalculated injection initiation angle with the intake valve closing angle.

[0103] When the recalculated injection initiation angle lags behind the intake valve closing angle S intk ,Right now ≤ intk， This indicates that the recalculated injection start angle is within a safe range. Based on the recalculated injection start angle and the updated injection end angle (preset latest injection end angle) in step S1031, the injection window is re-determined. If the re-determined injection window is within a safe range, the internal combustion engine injection parameter adjustment process ends, and the internal combustion engine is controlled to inject fuel according to the current injection parameters.

[0104] When the recalculated injection initiation angle is earlier than the intake valve closing angle S intk ,Right now > intk This indicates a potential for misfires in the internal combustion engine, and the ECU needs to adjust the current injection initiation angle to the preset earliest injection initiation angle. earliest Earliest injection start angle earliest equal to the intake valve closing angle intk Then proceed to step S1034.

[0105] Step S1034, based on the earliest injection initiation angle agSOI earlist Preset latest spray end angle latest and the inlet air rail temperature T rail and the target fuel injection mass M inj Calculate and generate the target fuel inlet rail pressure.

[0106] Specifically, based on the earliest injection initiation angle agSOI earlist Preset latest spray end angle latest and the inlet air rail temperature T rail and the target fuel injection mass M inj The calculation generates the target fuel inlet rail pressure, including:

[0107] According to the earliest injection initiation angle agSOI earlist Preset latest spray end angle latest and the engine speed Calculate and generate the second fuel injection pulse width

[0108] ;

[0109] Based on the second fuel injection pulse width The inlet air rail temperature T rail and the target fuel injection mass M inj (mg) Calculate to generate the target fuel inlet rail pressure

[0110] .

[0111] Step S1035, the target fuel inlet rail pressure With the maximum permissible fuel inlet rail pressure P railmax Compare:

[0112] When the target fuel inlet rail pressure Less than or equal to the maximum permissible fuel inlet rail pressure P railmax That is, P rail ≤P railmax This indicates the target fuel inlet rail pressure. If the setting range is correct, then the fuel inlet rail pressure P will be adjusted. rail Adjust to the target fuel inlet rail pressure Then return to step S102 to confirm the spray window.

[0113] When the target fuel inlet rail pressure Greater than the maximum permissible fuel inlet rail pressure P railmax That is, P rail >P railmax This indicates the target fuel inlet rail pressure. If the pressure exceeds the allowable range, the fuel inlet rail pressure will be reduced. Adjust to the maximum permissible fuel inlet rail pressure P railmax Then proceed to step S1036.

[0114] Step S1036, according to the maximum permissible fuel inlet rail pressure P railmax The inlet air rail temperature T rail Calculate the maximum fuel injection mass .

[0115] Specifically, the maximum fuel injection mass can be calculated using the following formula. :

[0116] ;

[0117] Here, and q is a preset constant. stat For the fuel inlet rail pressure of the internal combustion engine to be The inlet rail temperature of an internal combustion engine is The nozzle mass flow rate measurement value at that time.

[0118] Step S1037: Update the target fuel injection mass to the maximum fuel injection mass, and return to step S102 to confirm the injection window.

[0119] It should be noted that although the injection window is determined and the injection parameters are adjusted based on a preset injection start angle in this application, the injection window can also be determined and the injection parameters adjusted based on a preset injection end angle. The calculation and control principles are similar, so they will not be elaborated here.

[0120] In summary, to improve the safety of the hydrogen direct injection internal combustion engine injection system, this application requires the control terminal in the ECU to first acquire the current fuel inlet rail pressure, inlet rail temperature, engine speed, engine load, and target fuel injection mass of the internal combustion engine; calculate the current injection window of the internal combustion engine based on the fuel inlet rail pressure, inlet rail temperature, engine speed, engine load, and target fuel injection mass; compare the current injection window of the internal combustion engine with the ignition advance angle and intake valve closing angle of the internal combustion engine; and adjust the internal combustion engine injection parameters according to the comparison results to ensure that the injection window of the internal combustion engine is within a safe range. In other words, the adjustment method of this application can effectively monitor the injection window of a hydrogen direct injection internal combustion engine, covering all operating conditions of the engine. Moreover, when an abnormality is detected in the injection window, it can promptly feed back and calculate reasonable injection parameters, such as injection phase (injection start angle and injection end angle), injection rail pressure, and maximum target injection quantity, for adjustment and control. This avoids torque reduction and fluctuation in the hydrogen engine, exhaust pipe afterburning, and intake manifold backfire problems caused by an unreasonable injection window, greatly improving the robustness and reliability of the system.

[0121] Based on the same concept, such as Figure 5 As shown, this application also provides a device for adjusting injection parameters of a gas fuel direct injection internal combustion engine, comprising:

[0122] The information acquisition module 201 is used to acquire the current fuel inlet rail pressure, inlet rail temperature, engine speed, engine load and target fuel injection mass of the internal combustion engine.

[0123] Data calculation module 202 is used to calculate the injection window of the current internal combustion engine based on the fuel inlet rail pressure, inlet gas rail temperature, engine speed, engine load and target fuel injection mass;

[0124] The data comparison and adjustment module 203 is used to compare the current injection window of the internal combustion engine with the ignition advance angle and intake valve closing angle of the internal combustion engine, and adjust the injection parameters of the internal combustion engine according to the comparison results so that the injection window of the internal combustion engine is within a safe range.

[0125] It should be noted that the gas fuel direct injection internal combustion engine injection parameter adjustment device and the gas fuel direct injection internal combustion engine injection parameter adjustment method provided in the above embodiments belong to the same concept. The specific operation methods of each module and unit have been described in detail in the method embodiments and will not be repeated here. In practical applications, the gas fuel direct injection internal combustion engine injection parameter adjustment device provided in the above embodiments can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above. This is not a limitation here.

[0126] The above description of the embodiments shown in this application (including the content set forth in the abstract of the specification) is not intended to be an exhaustive enumeration or to limit this application to the precise forms disclosed herein. Although specific embodiments and examples of this application have been described herein for illustrative purposes only, various equivalent modifications are possible within the spirit and scope of this application, as will be recognized and understood by those skilled in the art. As indicated, these modifications can be made to this application in accordance with the above description of the embodiments described herein, and such modifications will be within the spirit and scope of this application.

[0127] This document has generally described the systems and methods in detail to aid in understanding the present application. Furthermore, various specific details have been provided to offer a general understanding of the embodiments of this application. However, those skilled in the art will recognize that embodiments of this application can be practiced without one or more specific details, or using other means, systems, accessories, methods, components, materials, parts, etc. In other instances, well-known structures, materials, and / or operations have not been specifically shown or described in detail to avoid obscuring various aspects of the embodiments of this application.

[0128] Therefore, although this application has been described herein with reference to specific embodiments thereof, freedom of modification, various changes and substitutions are also within the scope of the above disclosure, and it should be understood that in some cases, certain features of this application may be adopted without departing from the scope and spirit of the invention and without corresponding use of other features. Thus, many modifications can be made to adapt a particular environment or material to the essential scope and spirit of this application. This application is not intended to be limited to the specific terminology used in the following claims and / or the specific embodiments disclosed as the best mode of carrying out this application, but this application will include any and all embodiments and equivalents falling within the scope of the appended claims. Therefore, the scope of this application will be determined only by the appended claims.

Claims

1. A method of adjusting injection parameters of a gas fuel direct injection internal combustion engine, characterized by, The method comprises: acquiring a current fuel inlet rail pressure, a current inlet air rail temperature, an engine speed and an engine load of the internal combustion engine; calculating a current injection window of the internal combustion engine according to the current fuel inlet rail pressure, the current inlet air rail temperature, the engine speed, the engine load and a target fuel injection mass; comparing the current injection window of the internal combustion engine with an ignition advance angle and an intake valve closing angle of the internal combustion engine, and adjusting an injection parameter of the internal combustion engine according to a comparison result so that the injection window of the internal combustion engine is within a safety range; wherein the calculating of the current injection window of the internal combustion engine according to the current fuel inlet rail pressure, the current inlet air rail temperature, the engine speed and the target fuel injection mass comprises: matching a corresponding injection start angle from a preset angle table according to the engine speed and the engine load; calculating a first fuel injection pulse width according to the target fuel injection mass, the current fuel inlet rail pressure and the current inlet air rail temperature; calculating an injection end angle according to the first fuel injection pulse width, the engine speed and the injection start angle; generating the current injection window of the internal combustion engine based on the injection start angle and the injection end angle; the calculating of the first fuel injection pulse width according to the target fuel injection mass, the current fuel inlet rail pressure and the current inlet air rail temperature comprises: acquiring a fuel inlet label rail pressure, an inlet air label rail temperature and a nozzle mass flow measurement value when the current fuel inlet rail pressure and the current inlet air rail temperature of the internal combustion engine are the fuel inlet label rail pressure and the inlet air label rail temperature respectively; calculating the first fuel injection pulse width according to the fuel inlet label rail pressure, the inlet air label rail temperature, the nozzle mass flow measurement value, the target fuel injection mass, the current fuel inlet rail pressure and the current inlet air rail temperature.

2. The gas fuel direct injection internal combustion engine injection parameter adjustment method according to claim 1, characterized by, the calculating of the injection end angle according to the first fuel injection pulse width, the engine speed and the injection start angle comprises: calculating a product of the first fuel injection pulse width and the engine speed to obtain an injection intersection angle change value; calculating a difference between the injection start angle and the injection intersection angle change value as the injection end angle.

3. The gas fuel direct injection internal combustion engine injection parameter adjustment method according to claim 1, characterized by, the comparing of the current injection window of the internal combustion engine with the ignition advance angle and the intake valve closing angle of the internal combustion engine, and the adjusting of the injection parameter of the internal combustion engine according to the comparison result so that the injection window of the internal combustion engine is within the safety range comprises: when the injection end angle lags behind the ignition advance angle, assigning the injection end angle as a preset latest injection end angle; re-calculating an injection start angle based on the preset latest injection end angle, the first fuel injection pulse width and the engine speed; when the re-calculated injection start angle is ahead of the intake valve closing angle, assigning the injection start angle as an earliest injection start angle; calculating a target fuel inlet rail pressure according to the earliest injection start angle, the preset latest injection end angle, the current inlet air rail temperature and the target fuel injection mass; when the target fuel inlet rail pressure is greater than a maximum allowable fuel inlet rail pressure, adjusting the current fuel inlet rail pressure to the maximum allowable fuel inlet rail pressure; calculating a maximum fuel injection mass according to the maximum allowable fuel inlet rail pressure and the current inlet air rail temperature; The target fuel injection mass is updated to the maximum fuel injection mass, and the step of calculating the injection window of the current internal combustion engine according to the fuel inlet rail pressure, the inlet air rail temperature, the engine speed, the engine load, and the target fuel injection mass is returned to.

4. The gas fuel direct injection internal combustion engine injection parameter adjustment method according to claim 3, characterized by, The method further comprises, when the recalculated injection start angle is advanced relative to the ignition advance angle, ending the internal combustion engine injection parameter adjustment process.

5. The gas fuel direct injection internal combustion engine injection parameter adjustment method according to claim 3, characterized by, The method further comprises, when the injection start angle is lagged relative to the intake valve closing angle, ending the internal combustion engine injection parameter adjustment process.

6. The gas fuel direct injection internal combustion engine injection parameter adjustment method according to claim 3, characterized by, The method further comprises, when the target fuel inlet rail pressure is less than or equal to the maximum allowable fuel inlet rail pressure, adjusting the fuel inlet rail pressure to the target fuel inlet rail pressure, and returning to the step of calculating the injection window of the current internal combustion engine according to the fuel inlet rail pressure, the inlet air rail temperature, the engine speed, the engine load, and the target fuel injection mass.

7. The gas fuel direct injection internal combustion engine injection parameter adjustment method according to claim 3, characterized by, The target fuel inlet rail pressure is calculated according to the earliest injection start angle, the preset latest injection end angle, the inlet air rail temperature, and the target fuel injection mass, comprising: The second fuel injection pulse width is calculated according to the earliest injection start angle, the preset latest injection end angle, and the engine speed; The target fuel inlet rail pressure is calculated based on the second fuel injection pulse width, the inlet air rail temperature, and the target fuel injection mass.

8. An injection parameter adjustment device for a gaseous fuel direct injection internal combustion engine, the internal combustion engine adjustment injection parameter system comprising: An information acquisition module for acquiring the fuel inlet rail pressure, the inlet air rail temperature, the engine speed, and the engine load of the current internal combustion engine; A data calculation module for calculating the injection window of the current internal combustion engine according to the fuel inlet rail pressure, the inlet air rail temperature, the engine speed, the engine load, and the target fuel injection mass; A data comparison and adjustment module for comparing the injection window of the current internal combustion engine with the ignition advance angle and the intake valve closing angle of the internal combustion engine, and adjusting the injection parameters of the internal combustion engine according to the comparison result, so that the injection window of the internal combustion engine is within a safe range; The injection window of the current internal combustion engine is calculated according to the fuel inlet rail pressure, the inlet air rail temperature, the engine speed, and the target fuel injection mass, comprising: According to the engine speed and the engine load, the corresponding injection start angle is matched from a preset angle query table; The first fuel injection pulse width is calculated according to the target fuel injection mass, the fuel inlet rail pressure, and the inlet air rail temperature; The injection end angle is calculated according to the first fuel injection pulse width, the engine speed, and the injection start angle; The injection window of the current internal combustion engine is generated based on the injection start angle and the injection end angle; The first fuel injection pulse width is calculated according to the target fuel injection mass, the fuel inlet rail pressure, and the inlet air rail temperature, comprising: The fuel inlet rail pressure, the inlet air rail temperature, and the nozzle mass flow measurement value when the fuel inlet rail pressure of the internal combustion engine is the fuel inlet rail pressure and the inlet air rail temperature is the inlet air rail temperature are acquired; The first fuel injection pulse width is calculated based on the rail pressure, the fuel inlet gas rail temperature, the nozzle mass flow measurement, the target fuel injection mass, the fuel inlet rail pressure, and the inlet gas rail temperature.

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