Natural gas engine gas component detection method and device and vehicle

Abstract

The invention discloses a natural gas engine gas quality component detection method and device and a vehicle, which can comprehensively evaluate gas quality components of a natural gas engine through a motor feedback torque, an excess air coefficient and a knock signal so as to more accurately judge the influence of the gas quality components on knock. The natural gas engine gas component detection method comprises the steps of obtaining a vibration signal of natural gas engine cylinder combustion; when the vibration signal is larger than or equal to a preset knock threshold value, the natural gas engine is adjusted to a preset gas quality detection point, and the motor feedback torque, the excess air coefficient and the knock signal at the preset gas quality detection point are obtained; calculating a gas knock influence coefficient based on the motor feedback torque, the excess air coefficient and the knock signal; and when the gas knock influence coefficient is larger than or equal to a preset threshold value, it is determined that the natural gas engine is knocked due to gas influence, and the gas component difference of the natural gas engine is determined.

Description

Technical Field

[0001] This application relates to the field of natural gas engine technology, specifically to a method, apparatus, and vehicle for detecting the gas composition of a natural gas engine. Background Technology

[0002] Natural gas, as a clean energy source, is widely used in the automotive and power sectors. Compared to gasoline or diesel engines, natural gas engines have advantages such as lower emissions and lower operating costs. However, natural gas engines also face some unique technical challenges in actual operation, among which knocking during combustion is particularly prominent. Currently, engines are typically equipped with knock sensors to monitor vibration signals and determine whether knocking has occurred. However, existing technologies struggle to effectively distinguish and determine whether knocking is caused by changes in gas composition. Conventional knock monitoring systems can only determine whether knocking has occurred, but cannot identify the triggers. Since numerous factors can lead to knocking, such as improper ignition timing, cooling system malfunctions, and carbon buildup, without accurately identifying the influence of gas composition, targeted adjustments to control strategies are impossible. Summary of the Invention

[0003] To address the aforementioned technical problems, this application is proposed. Embodiments of this application provide a method, apparatus, and vehicle for detecting the gas composition of a natural gas engine. This method can comprehensively evaluate the gas composition of a natural gas engine by utilizing motor feedback torque, excess air coefficient, and knock signal, thereby more accurately determining the impact of gas composition on knock.

[0004] According to a first aspect of this application, a method for detecting the gas composition of a natural gas engine is provided, comprising: acquiring a vibration signal of combustion in a natural gas engine cylinder; when the vibration signal is greater than or equal to a preset knock threshold, adjusting the natural gas engine to a preset gas composition detection point, and acquiring the motor feedback torque, excess air coefficient, and knock signal at the preset gas composition detection point; calculating a gas composition knock influence coefficient based on the motor feedback torque, the excess air coefficient, and the knock signal; and determining that the natural gas engine has knocked due to the gas composition influence when the gas composition knock influence coefficient is greater than or equal to the preset threshold, thereby determining the gas composition difference of the natural gas engine.

[0005] As one possible implementation, the natural gas engine gas composition detection method further includes: when the natural gas engine experiences detonation due to gas composition, issuing an indicator light and performing low-detonation power generation optimization; wherein, the low-detonation power generation optimization refers to adjusting the operating point.

[0006] As one possible implementation method, low-detonation power generation optimization includes: adjusting the current set operating point until the vibration signal is less than a preset detonation threshold, and recording the adjusted first gas consumption rate; based on the set operating point, sequentially increasing the rotational speed and decreasing the torque along a preset power line to obtain at least one second operating point with a second gas consumption rate; when any second gas consumption rate increases compared to the first gas consumption rate or the previous second gas consumption rate, the lowest point among the second gas consumption rates is taken as the second operating point; based on the set operating point, sequentially decreasing the rotational speed and increasing the torque along a preset power line to obtain at least one third operating point with a third gas consumption rate; when any third gas consumption rate increases compared to the second gas consumption rate or the previous third gas consumption rate, the lowest point among the third gas consumption rates is taken as the optimal power generation point under the current power demand.

[0007] As one possible implementation, when any second gas consumption rate increases compared to the first gas consumption rate or the previous second gas consumption rate, the lowest point among the second gas consumption rates is taken as the second operating point, including: when any second gas consumption rate decreases compared to the first gas consumption rate, increasing the rotational speed and decreasing the torque along a preset power line until any second gas consumption rate increases compared to the previous second gas consumption rate, and taking the lowest point among the second gas consumption rates as the second operating point; when any third gas consumption rate increases compared to the second gas consumption rate or the previous third gas consumption rate, the lowest point among the third gas consumption rates is taken as the optimal power generation point under the current demand power, including: when any third gas consumption rate decreases compared to the second gas consumption rate, decreasing the rotational speed and increasing the torque along a preset power line until any third gas consumption rate increases compared to the previous third gas consumption rate, and taking the lowest point among the third gas consumption rates as the optimal power generation point under the current demand power.

[0008] As one possible implementation, when the vibration signal is greater than or equal to a preset knock threshold, the natural gas engine gas composition detection method further includes: detecting the boundary conditions of the natural gas engine; wherein the boundary conditions of the natural gas engine include engine coolant temperature, intake manifold temperature, and ambient temperature; wherein adjusting the natural gas engine to a preset gas composition detection point and acquiring the motor feedback torque, excess air coefficient, and knock signal at the preset gas composition detection point includes: when the boundary conditions of the natural gas engine meet the following three conditions: the natural gas engine coolant temperature is within a preset coolant temperature range, the intake manifold temperature is within a preset temperature range, and the ambient temperature is within a preset ambient temperature range, adjusting the natural gas engine to the preset gas composition detection point and acquiring the motor feedback torque, excess air coefficient, and knock signal at the preset gas composition detection point.

[0009] As one possible implementation, after adjusting the engine to a preset gas composition detection point, the natural gas engine gas composition detection method further includes: adjusting the electronic control parameters of the natural gas engine to a preset electronic control parameter range; wherein, the electronic control parameters include advance angle, EGR valve opening, throttle opening, and exhaust valve opening; wherein, acquiring the motor feedback torque, excess air coefficient, and knock signal at the preset gas composition detection point includes: acquiring the motor feedback torque, excess air coefficient, and knock signal at the preset gas composition detection point when the electronic control parameters of the natural gas engine are adjusted to the preset electronic control parameter range.

[0010] As one possible implementation, the gas detonation influence coefficient is calculated based on the motor feedback torque, the excess air coefficient, and the detonation signal, including: calculating the torque detonation coefficient based on the motor feedback torque; calculating the excess air detonation coefficient based on the excess air coefficient; calculating the integral detonation coefficient based on the detonation signal; and calculating the gas detonation influence coefficient based on the torque detonation coefficient and its preset weighting coefficient, the excess air detonation coefficient and its preset weighting coefficient, and the integral detonation coefficient and its preset weighting coefficient.

[0011] As one possible implementation, the natural gas engine gas composition detection method further includes: determining a preset weighting coefficient for the torque knock coefficient, a preset weighting coefficient for the excess air knock coefficient, and a preset weighting coefficient for the integral knock coefficient based on the intake air temperature and water temperature.

[0012] According to a second aspect of this application, a natural gas engine gas composition detection device is provided, comprising: an acquisition module for acquiring vibration signals of combustion in the cylinder of a natural gas engine; an adjustment module for adjusting the natural gas engine to a preset gas composition detection point when the vibration signal is greater than or equal to a preset knock threshold, and acquiring the motor feedback torque, excess air coefficient, and knock signal at the preset gas composition detection point; a calculation module for calculating a gas composition knock influence coefficient based on the motor feedback torque, the excess air coefficient, and the knock signal; and a determination module for determining that the natural gas engine has experienced knocking due to gas composition influence when the gas composition knock influence coefficient is greater than or equal to the preset threshold, thereby determining the gas composition difference of the natural gas engine.

[0013] According to a third aspect of this application, a vehicle is provided, comprising: a natural gas engine; and a natural gas engine gas composition detection device as described in the second aspect or any implementation thereof, the natural gas engine gas composition detection device being communicatively connected to the natural gas engine.

[0014] The natural gas engine gas composition detection method, device, and vehicle provided in this application, after obtaining a vibration signal, determine whether knocking has occurred based on the comparison result between the vibration signal and a preset knocking threshold. If knocking occurs, the natural gas engine is adjusted to a preset gas composition detection point, and the motor feedback torque, excess air coefficient, and knocking signal at this time are obtained. The motor feedback torque, excess air coefficient, and knocking signal provide multi-source information about the natural gas engine. By comprehensively evaluating the gas composition of the natural gas engine through multi-source information, the influence of gas composition on knocking can be more accurately determined. Attached Figure Description

[0015] The above and other objects, features, and advantages of this application will become more apparent from the more detailed description of the embodiments of this application in conjunction with the accompanying drawings. The drawings are provided to further illustrate the embodiments of this application and form part of the specification. They are used together with the embodiments of this application to explain this application and do not constitute a limitation thereof. In the drawings, the same reference numerals generally represent the same components or steps.

[0016] Figure 1 This is a schematic flowchart of a natural gas engine gas composition detection method provided in an exemplary embodiment of this application.

[0017] Figure 2 This is a schematic diagram of the structure of a natural gas engine gas composition detection device provided in an exemplary embodiment of this application.

[0018] Figure 3 This is a structural diagram of an electronic device provided in an exemplary embodiment of this application. Detailed Implementation

[0019] Hereinafter, exemplary embodiments according to this application will be described in detail with reference to the accompanying drawings. Obviously, the described embodiments are merely some embodiments of this application, and not all embodiments of this application. It should be understood that this application is not limited to the exemplary embodiments described herein.

[0020] Natural gas, as a clean fuel, has methane, its core component, which possesses high octane ratings and low auto-ignition temperatures, theoretically giving it excellent anti-knock properties. While methane, the main component of natural gas, has a high octane rating and should ideally provide good anti-knock performance, the relatively slow flame propagation speed of natural gas makes its combustion process more sensitive to changes in operating conditions and fuel composition. In practical applications, pipeline natural gas comes from diverse sources, and its gas composition (such as methane rating, high-carbon hydrocarbon content, inert gas ratio, and hydrogen content) fluctuates. Changes in gas composition directly affect the combustion characteristics of the mixture, including laminar flame velocity, ignition delay period, and adiabatic flame temperature. For example, when the proportion of high-carbon hydrocarbons (such as ethane and propane) in the fuel increases or the methane rating decreases, the anti-knock performance of the mixture decreases, and the flame propagation speed may also change.

[0021] Under specific operating conditions, such as high load, high coolant temperature, and an excessively advanced ignition advance angle (in an internal combustion engine, the time when the spark plug ignites the air-fuel mixture or the crankshaft angle relative to the time the piston reaches top dead center), the temperature and pressure inside the cylinder will significantly increase. If, at this time, the composition of the combustion gas happens to shift towards a state conducive to knocking, the mixture at the end of the combustion chamber may spontaneously combust before the normal flame front arrives, generating violent pressure oscillations, i.e., knocking. In other words, knocking refers to the uncontrolled spontaneous combustion phenomenon that occurs during the operation of an internal combustion engine due to factors such as compression, temperature, or pressure, leading to an irregular combustion process and generating violent shock waves and vibrations. Severe knocking can cause a series of damages to the engine: First, it generates high-frequency pressure waves that violently impact components such as the cylinder walls, piston tops, and valves, leading to abnormal wear and even mechanical damage; second, knocking produces a sharp metallic knocking sound, causing noise pollution and affecting driving comfort; third, knocking disrupts the normal combustion process, resulting in a significant decrease in engine economy and power; finally, abnormal combustion also leads to an increase in incomplete combustion products, causing emissions to worsen, such as an increase in nitrogen oxides (NOx) and hydrocarbons (HC) emissions.

[0022] Currently, engines are typically equipped with knock sensors to monitor vibration signals and determine whether knocking has occurred. However, existing technology cannot effectively distinguish and determine whether knocking is caused by changes in gas composition, which affects subsequent control strategies and prevents the achievement of efficient and clean combustion.

[0023] To solve the above problems, Figure 1 This is a schematic flowchart of a natural gas engine gas composition detection method provided in an exemplary embodiment of this application. Figure 1 For example, firstly, the vibration signal of combustion in the cylinder of a natural gas engine is acquired (see...). Figure 1(S110). Secondly, when the vibration signal is greater than or equal to the preset knock threshold, the natural gas engine is adjusted to the preset gas quality detection point, and the motor feedback torque, excess air coefficient, and knock signal at the preset gas quality detection point are obtained (see S110). Figure 1 (S120). Then, based on the motor feedback torque, excess air coefficient, and knock signal, the gas detonation influence coefficient is calculated (see S120). Figure 1 (S130). Finally, when the gas-gas knocking influence coefficient is greater than or equal to a preset threshold, it is determined that the natural gas engine is knocked due to the gas-gas influence, so as to determine the gas-gas composition difference of the natural gas engine (see S130). Figure 1 (S140). When knocking occurs in a natural gas engine, the current state of the engine is detected, and the gas-gas knocking influence coefficient is calculated by comprehensively considering the motor feedback torque, excess air coefficient, and knocking signal. The gas-gas knocking influence coefficient reflects the gas-gas composition, comprehensively evaluates the gas-gas composition of the natural gas engine, and accurately determines the influence of gas-gas composition on knocking.

[0024] In some embodiments, the natural gas engine in a range extender differs from a conventional engine. The natural gas engine in a range extender is specifically designed for power generation, with the core objective of continuously and stably outputting electrical energy. Consequently, the flame propagation speed of a natural gas engine is slow, and it is susceptible to knocking under conditions of high load, high water temperature, and advanced ignition timing, influenced by changes in gas composition. Knocking can cause wear on components, increased noise, reduced fuel economy and power, and worsened emissions. The aforementioned natural gas engine gas composition detection method can be applied to the natural gas engine in a range extender. When knocking occurs, the current state of the engine can be monitored to determine if gas composition is affecting combustion and causing knocking.

[0025] The following text combines Figure 1 The method for detecting the gas composition of a natural gas engine provided in the embodiments of this application will be described in more detail.

[0026] In S110, the vibration signal of combustion in the cylinder of the natural gas engine is acquired.

[0027] In some embodiments, a knock sensor can be used to detect combustion vibration signals in the cylinders of a natural gas engine. The knock sensor operates based on the piezoelectric effect, and its core component is a piezoelectric ceramic or piezoelectric crystal. When knock occurs within the engine cylinder, the shock wave generated by combustion induces cylinder block vibration, and the vibration energy is transferred to the sensor through a mechanical structure. When the piezoelectric element is subjected to the pressure generated by the vibration, its internal crystal structure deforms, generating a charge proportional to the vibration intensity. The frequency range of the vibration signal is typically concentrated in the main combustion stage of the natural gas engine, and the intensity of the vibration signal increases with the increase of the knock intensity.

[0028] See also Figure 1In S120, when the vibration signal is greater than or equal to the preset knock threshold, the natural gas engine is adjusted to the preset gas quality detection point, and the motor feedback torque, excess air coefficient and knock signal at the preset gas quality detection point are obtained.

[0029] If the vibration signal exceeds the preset detonation threshold and persists for a certain period of time, the detonation is considered too high. Determining that the detonation is too high only after a sustained period of time can rule out situations where detonation is caused by excessively rapid transients.

[0030] The motor feedback torque here is the actual measured torque of the motor. The excess air coefficient refers to the ratio of the actual amount of air supplied to the theoretical amount of air required for complete combustion of fuel. The knock signal is the vibration signal detected by the knock sensor, and is defined as the knock signal when knocking occurs.

[0031] In some embodiments, after knocking occurs, the boundary conditions of the natural gas engine can be detected. These boundary conditions include engine coolant temperature, intake manifold temperature, and ambient temperature. When the boundary conditions of the natural gas engine meet the following three conditions: the natural gas engine coolant temperature is within a preset coolant temperature range, the intake manifold temperature is within a preset temperature range, and the ambient temperature is within a preset ambient temperature range, it is considered that the knocking is not caused by these conditions. At this point, the function is enabled, the natural gas engine is adjusted to a preset gas composition detection point, and the motor feedback torque, excess air coefficient, and knocking signal at the preset gas composition detection point are acquired to detect the quality of the gas composition.

[0032] In some embodiments, the engine is first adjusted to a preset gas quality detection point by the range extender. The preset gas quality detection point is set in advance during the product development process and should meet the characteristics of high load, high knocking, and easy knocking.

[0033] Next, it is confirmed that the engine boundaries are within the preset threshold to ensure that the boundaries will not affect the occurrence of knock. The electronic control parameters of the natural gas engine are adjusted to the preset range. These parameters include the advance angle, EGR (Exhaust Gas Recirculation) valve opening, throttle opening, and wastegate opening. As one possible implementation, the electronic control parameters of the natural gas engine can be adjusted to be consistent with those used during the engine's development. Currently, when knock occurs, the electronic control parameters are adjusted to reduce knock. When the electronic control parameters of the natural gas engine are adjusted to the preset range, the motor feedback torque, excess air coefficient, and knock signal are acquired at the preset gas quality detection point.

[0034] See also Figure 1 In S130, the gas detonation influence coefficient is calculated based on the motor feedback torque, excess air coefficient, and detonation signal.

[0035] In some embodiments, motor feedback torque, excess air coefficient, and knock signal are introduced as parameters for calculating the gas detonation influence coefficient. For example, the torque detonation coefficient is calculated based on the motor feedback torque; the excess air detonation coefficient is calculated based on the excess air coefficient; the integral detonation coefficient is calculated based on the knock signal; and the gas detonation influence coefficient is calculated based on the torque detonation coefficient and its preset weighting coefficients, the excess air detonation coefficient and its preset weighting coefficients, and the integral detonation coefficient and its preset weighting coefficients.

[0036] One possible formula for calculating the torque knock coefficient is: Formula 1; In Formula 1, This refers to the torque knock coefficient. This is the motor feedback torque (i.e., the actual measured torque of the motor). To preset the required torque, t The sampling period is The maximum torque within the sampling period. The minimum torque within the sampling period, This is the torque fluctuation threshold.

[0037] One possible formula for calculating the excess air knock factor is: Formula 2; In Formula 2, Excess air coefficient and knock coefficient. An oxygen sensor is used to measure the oxygen content in exhaust gas. To set up an oxygen sensor to measure the oxygen content in exhaust gas, For fresh air flow, To set the excess air coefficient, This is the amount of air required for theoretically complete combustion.

[0038] One possible formula for calculating the integral knock coefficient is: Formula 3; In Formula 3, The integral detonation coefficient, The signal is the processed knock signal from the knock sensor, and RKR is the engine background noise.

[0039] A possible formula for calculating the gas-air knock influence coefficient after adding weighting factors based on the torque knock coefficient, excess air knock coefficient, and integral knock coefficient is: Formula 4; In Formula 4, τ is the gas detonation influence coefficient, a1 is the preset weighting coefficient of the torque detonation coefficient, a2 is the preset weighting coefficient of the excess air detonation coefficient, and a3 is the preset weighting coefficient of the integral detonation coefficient. This refers to the torque knock coefficient. Excess air coefficient and knock coefficient. This is the integral detonation coefficient.

[0040] As one possible implementation, the three preset weighting coefficients here need to be tested in advance on a bench to determine the relationship between different coolant temperatures, intake air temperatures, and corresponding variables. In actual use, the corresponding coefficients are obtained by referring to the preset MAP based on the intake air temperature and coolant temperature. Therefore, based on the intake air temperature and coolant temperature, the preset weighting coefficients for torque knock coefficient, excess air knock coefficient, and integral knock coefficient are determined. It can be assumed that the effects of intake air temperature, coolant temperature, and gas composition on the engine's actual output power, excess air coefficient, and knock are different; therefore, the corresponding weighting coefficients are calibrated under different conditions. By fully considering factors such as coolant temperature and intake air temperature, and comprehensively judging gas composition, the accuracy of the final judgment result can be improved.

[0041] See also Figure 1 In S140, when the gas detonation influence coefficient is greater than or equal to a preset threshold, it is determined that the natural gas engine is detonated due to the gas composition, so as to determine the gas composition difference of the natural gas engine.

[0042] According to the gas composition knocking influence coefficient, when the gas composition knocking influence coefficient is greater than or equal to the preset threshold, it is considered that knocking has occurred due to the influence of gas composition. At this time, the gas composition is poor. The higher the coefficient, the worse the gas composition is considered. When the natural gas engine knocks due to the influence of gas composition, an error warning light is issued and low knocking power generation optimization is performed.

[0043] In some embodiments, when it is determined that the natural gas engine is experiencing detonation due to the influence of gas atmosphere based on the gas atmosphere detonation influence coefficient, low-detonation power generation optimization is performed. Low-detonation power generation optimization refers to adjusting the operating point.

[0044] As a possible approach to optimizing low-knock power generation, the current set operating point is adjusted until the vibration signal is less than a preset knock threshold, and the first gas consumption rate after adjustment is recorded. The actual operating point of the current set operating point, i.e., the point where knocking occurs during actual operation, is used to obtain a second gas consumption rate at least at a second operating point by sequentially increasing the engine speed and decreasing the torque along a preset power line, based on the set operating point. In other words, the engine adjusts its electronic control parameters to reduce knocking until it falls below the knock threshold. The gas consumption rate deteriorates during this adjustment process, and the current gas consumption rate is measured and recorded after adjustment. For example, when any second gas consumption rate increases compared to the first gas consumption rate or the previous second gas consumption rate, the lowest point among the second gas consumption rates is taken as the second operating point. This means that when any second air consumption rate decreases compared to the first air consumption rate, the engine speed continues to increase and the torque decreases along a preset power line until any second air consumption rate increases compared to the previous second air consumption rate. At this point, since the rate begins to increase, the previous second air consumption rate is at its lowest point, and this lowest point among the second air consumption rates is taken as the second operating point. If, after the first increase in engine speed and decrease in torque, the second air consumption rate increases compared to the first air consumption rate, then the engine speed and torque are not further increased or decreased.

[0045] Next, based on the set operating point, the engine speed is increased and the torque is decreased sequentially along the preset power line to obtain at least one third operating point with a third gas consumption rate. When any third gas consumption rate increases compared to the second or previous third gas consumption rate, the point with the lowest third gas consumption rate is taken as the optimal power generation point for the current demand. For example, when any third gas consumption rate decreases compared to the second gas consumption rate, the engine speed is decreased and the torque is increased along the preset power line until any third gas consumption rate increases compared to the previous third gas consumption rate. The point with the lowest third gas consumption rate is then taken as the optimal power generation point for the current demand. Compared to directly adjusting the electronic control parameters in current technology, judging gas consumption sequentially by adjusting the operating conditions and selecting the optimal power generation operating point can improve economic efficiency and provide more flexible power generation operating condition selection in the event of knocking.

[0046] Figure 2 This is a schematic diagram of the structure of a natural gas engine gas composition detection device provided in an exemplary embodiment of this application, as shown below. Figure 2As shown, the natural gas engine gas composition detection device 2 includes: an acquisition module 21 for acquiring vibration signals from the combustion of natural gas engine cylinders; an adjustment module 22 for adjusting the natural gas engine to a preset gas composition detection point when the vibration signal is greater than or equal to a preset knock threshold, and acquiring the motor feedback torque, excess air coefficient, and knock signal at the preset gas composition detection point; a calculation module 23 for calculating the gas composition knock influence coefficient based on the motor feedback torque, excess air coefficient, and knock signal; and a determination module 24 for determining that the natural gas engine has experienced knocking due to gas composition influence when the gas composition knock influence coefficient is greater than or equal to a preset threshold, thereby determining the gas composition difference of the natural gas engine.

[0047] As one possible implementation, the natural gas engine gas composition detection device 2 may further include: when the natural gas engine experiences detonation due to gas composition, issuing an indicator light and performing low-detonation power generation optimization; wherein, low-detonation power generation optimization means adjusting the operating point.

[0048] As one possible implementation, the natural gas engine gas composition detection device 2 may further include: adjusting the current set operating point until the vibration signal is less than a preset knock threshold, and recording the adjusted first gas consumption rate; based on the set operating point, sequentially increasing the speed and decreasing the torque along a preset power line to obtain at least one second operating point with a second gas consumption rate; when any second gas consumption rate increases compared to the first gas consumption rate or the previous second gas consumption rate, taking the lowest point among the second gas consumption rates as the second operating point; based on the set operating point, sequentially decreasing the speed and increasing the torque along a preset power line to obtain at least one third operating point with a third gas consumption rate; when any third gas consumption rate increases compared to the second gas consumption rate or the previous third gas consumption rate, taking the lowest point among the third gas consumption rates as the optimal power generation point under the current demand power.

[0049] As one possible implementation, the natural gas engine gas composition detection device 2 may further include: when any second gas consumption rate decreases compared to the first gas consumption rate, increasing the rotational speed and decreasing the torque along a preset power line until any second gas consumption rate increases compared to the previous second gas consumption rate, and taking the lowest point among the second gas consumption rates as the second operating point; when any third gas consumption rate decreases compared to the second gas consumption rate, decreasing the rotational speed and increasing the torque along a preset power line until any third gas consumption rate increases compared to the previous third gas consumption rate, and taking the lowest point among the third gas consumption rates as the optimal power generation point under the current demand power.

[0050] As one possible implementation, when the vibration signal is greater than or equal to a preset knock threshold, the natural gas engine gas composition detection device 2 may further include: detecting the boundary conditions of the natural gas engine; wherein, the boundary conditions of the natural gas engine include engine coolant temperature, intake manifold temperature, and ambient temperature; wherein, adjusting the natural gas engine to a preset gas composition detection point and acquiring the motor feedback torque, excess air coefficient, and knock signal at the preset gas composition detection point includes: when the boundary conditions of the natural gas engine meet the following three conditions: the natural gas engine coolant temperature is within a preset coolant temperature range, the intake manifold temperature is within a preset temperature range, and the ambient temperature is within a preset ambient temperature range, adjusting the natural gas engine to the preset gas composition detection point and acquiring the motor feedback torque, excess air coefficient, and knock signal at the preset gas composition detection point.

[0051] As one possible implementation, after adjusting the engine to a preset gas composition detection point, the natural gas engine gas composition detection device 2 may further include: adjusting the electronic control parameters of the natural gas engine to a preset electronic control parameter range; wherein the electronic control parameters include advance angle, EGR valve opening, throttle opening, and exhaust valve opening; wherein acquiring the motor feedback torque, excess air coefficient, and knock signal at the preset gas composition detection point includes: acquiring the motor feedback torque, excess air coefficient, and knock signal at the preset gas composition detection point when the electronic control parameters of the natural gas engine are adjusted to the preset electronic control parameter range.

[0052] As one possible implementation, the calculation module 23 can be configured to: calculate the torque knock coefficient based on the motor feedback torque; calculate the excess air knock coefficient based on the excess air coefficient; calculate the integral knock coefficient based on the knock signal; and calculate the gas knock influence coefficient based on the torque knock coefficient and its preset weighting coefficient, the excess air knock coefficient and its preset weighting coefficient, and the integral knock coefficient and its preset weighting coefficient.

[0053] As one possible implementation, the natural gas engine gas composition detection device 2 may further include: determining a preset weighting coefficient for the torque knock coefficient, a preset weighting coefficient for the excess air knock coefficient, and a preset weighting coefficient for the integral knock coefficient based on the intake air temperature and water temperature.

[0054] In some embodiments, the natural gas engine gas composition detection device can be applied to a vehicle, which includes a natural gas engine. The natural gas engine gas composition detection device is communicatively connected to the natural gas engine. When the natural gas engine experiences knocking, the device can comprehensively determine the gas composition by utilizing multi-source information such as motor torque, oxygen sensor, and knocking signal, while fully considering factors such as water temperature and intake air temperature. This allows for the determination of the gas composition's impact on knocking, and by adjusting the operating conditions, the optimal gas consumption power generation point can be selected. This provides a more flexible power generation operating condition selection when knocking occurs, thereby improving the safety of the natural gas engine and ultimately enhancing the safety of vehicle use.

[0055] An electronic device includes: a processor; a memory for storing processor-executable instructions; and a processor for executing the natural gas engine gas composition detection method provided in this application.

[0056] Below, for reference Figure 3 This application describes an electronic device according to embodiments thereof. The electronic device may be either or both of a first device and a second device, or a standalone device independent of them, which may communicate with the first device and the second device to receive acquired input signals from them.

[0057] Figure 3 A block diagram of an electronic device according to an embodiment of this application is illustrated.

[0058] like Figure 3 As shown, the electronic device 30 includes one or more processors 31 and memory 32.

[0059] The processor 31 may be a central processing unit (CPU) or other form of processing unit with data processing and / or instruction execution capabilities, and may control other components in the electronic device 30 to perform desired functions.

[0060] The memory 32 may include one or more computer program products, which may include various forms of computer-readable storage media, such as volatile memory and / or non-volatile memory. Volatile memory may include, for example, random access memory (RAM) and / or cache memory. Non-volatile memory may include, for example, read-only memory (ROM), hard disk, flash memory, etc. One or more computer program instructions may be stored on the computer-readable storage medium, and the processor 31 may execute the program instructions to implement the natural gas engine gas composition detection method of the various embodiments of this application described above and / or other desired functions. Various contents such as input signals, signal components, and noise components may also be stored in the computer-readable storage medium.

[0061] In one example, the electronic device 30 may also include an input device 33 and an output device 34, which are interconnected via a bus system and / or other forms of connection mechanism (not shown).

[0062] When the electronic device is a standalone device, the input device 33 can be a communication network connector for receiving the collected input signals from the first device and the second device.

[0063] In addition, the input device 33 may also include, for example, a keyboard, a mouse, etc.

[0064] The output device 34 can output various information to the outside, including determined distance information, direction information, etc. The output device 34 may include, for example, a display, a speaker, a printer, and a communication network and its connected remote output devices, etc.

[0065] Of course, for the sake of simplicity, Figure 3 Only some of the components of the electronic device 30 relevant to this application are shown in this illustration; components such as buses, input / output interfaces, etc., are omitted. In addition, the electronic device 30 may include any other suitable components depending on the specific application.

[0066] Computer program products can be written in any combination of one or more programming languages ​​to perform the operations of the embodiments of this application. The programming languages ​​include object-oriented programming languages ​​such as Java and C++, as well as conventional procedural programming languages ​​such as C or similar languages. The program code can be executed entirely on the user's computing device, partially on the user's computing device, as a standalone software package, partially on the user's computing device and partially on a remote computing device, or entirely on a remote computing device or server.

[0067] A computer-readable storage medium stores a computer program for executing the natural gas engine gas composition detection method of the embodiments provided in this application.

[0068] Computer-readable storage media may take the form of any combination of one or more readable media. A readable medium may be a readable signal medium or a readable storage medium. A readable storage medium may, for example, include, but is not limited to, electrical, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatuses, or devices, or any combination thereof. More specific examples of readable storage media (a non-exhaustive list) include: electrical connections having one or more wires, portable disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fibers, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof.

[0069] The above description has been given for purposes of illustration and description. Furthermore, this description is not intended to limit the embodiments of this application to the forms disclosed herein. Although numerous exemplary aspects and embodiments have been discussed above, those skilled in the art will recognize certain variations, modifications, alterations, additions, and sub-combinations thereof.

Claims

1. A method for detecting gas chemistry components in a natural gas engine, characterized in that, include: Acquire vibration signals from combustion in the cylinders of a natural gas engine; When the vibration signal is greater than or equal to the preset knock threshold, the natural gas engine is adjusted to the preset gas quality detection point, and the motor feedback torque, excess air coefficient and knock signal at the preset gas quality detection point are obtained. Based on the motor feedback torque, the excess air coefficient, and the knock signal, calculate the gas detonation influence coefficient; When the gas detonation influence coefficient is greater than or equal to a preset threshold, it is determined that the natural gas engine is detonated due to the gas composition, so as to determine the gas composition difference of the natural gas engine.

2. The method for detecting gas composition in a natural gas engine according to claim 1, characterized in that, Also includes: When the natural gas engine experiences detonation due to gas conditions, a warning light is emitted and a low-detonation power generation optimization is initiated; wherein, the low-detonation power generation optimization refers to adjusting the operating point.

3. The method for detecting gas composition in a natural gas engine according to claim 2, characterized in that, Optimization of low-detonation power generation includes: Adjust the current operating point until the vibration signal is less than the preset knock threshold, and record the first gas consumption rate after adjustment. Based on the set operating point, the speed is increased and the torque is decreased sequentially along the preset power line to obtain a second gas consumption rate at at least one second operating point; When any second gas consumption rate increases compared to the first gas consumption rate or the previous second gas consumption rate, the lowest point among the second gas consumption rates is taken as the second operating point. Based on the set operating point, the speed is reduced and the torque is increased sequentially along the preset power line to obtain at least one third operating point of third gas consumption rate. When any third gas consumption rate increases compared to the second gas consumption rate or the previous third gas consumption rate, the point with the lowest third gas consumption rate is taken as the optimal power generation point under the current power demand.

4. The method for detecting gas composition in a natural gas engine according to claim 3, characterized in that, When any second gas consumption rate increases compared to the first gas consumption rate or the previous second gas consumption rate, the lowest point among the second gas consumption rates is taken as the second operating point, including: When any second gas consumption rate decreases compared to the first gas consumption rate, the speed is increased and the torque is decreased along the preset power line until any second gas consumption rate increases compared to the previous second gas consumption rate. The point with the lowest second gas consumption rate is taken as the second operating point. When any third gas consumption rate increases compared to the second or previous third gas consumption rate, the point with the lowest third gas consumption rate is taken as the optimal power generation point under the current power demand, including: When any third gas consumption rate decreases compared to the second gas consumption rate, the speed is reduced and the torque is increased along the preset power line until any third gas consumption rate increases compared to the previous third gas consumption rate. The point with the lowest third gas consumption rate is then taken as the optimal power generation point under the current power demand.

5. The method for detecting gas composition in a natural gas engine according to claim 1, characterized in that, When the vibration signal is greater than or equal to a preset knock threshold, the natural gas engine gas composition detection method further includes: Detecting the boundary conditions of a natural gas engine; wherein the boundary conditions of the natural gas engine include engine coolant temperature, intake manifold temperature, and ambient temperature; The process includes adjusting the natural gas engine to a preset gas quality detection point and acquiring the motor feedback torque, excess air coefficient, and knock signal at that preset gas quality detection point, including: When the boundary conditions of the natural gas engine meet the following three conditions: the natural gas engine water temperature is within a preset water temperature range, the intake manifold temperature is within a preset temperature range, and the ambient temperature is within a preset ambient temperature range, the natural gas engine is adjusted to a preset gas quality detection point, and the motor feedback torque, excess air coefficient, and knock signal at the preset gas quality detection point are obtained.

6. The method for detecting gas composition in a natural gas engine according to claim 1, characterized in that, After adjusting the engine to the preset gas composition detection point, the gas composition detection method for natural gas engines also includes: Adjust the electronic control parameters of the natural gas engine to the preset electronic control parameter range; wherein, the electronic control parameters include advance angle, EGR valve opening, throttle opening and exhaust valve opening; The acquisition of motor feedback torque, excess air coefficient, and knock signal at the preset gas quality detection point includes: When the electronic control parameters of the natural gas engine are adjusted to the preset electronic control parameter range, the motor feedback torque, excess air coefficient and knock signal at the preset gas detection point are acquired.

7. The method for detecting gas composition in a natural gas engine according to claim 1, characterized in that, Based on the motor feedback torque, the excess air coefficient, and the knock signal, the gas detonation influence coefficient is calculated, including: Calculate the torque knock coefficient based on the motor feedback torque; Calculate the excess air knock coefficient based on the aforementioned excess air coefficient; Calculate the integral detonation coefficient based on the detonation signal; The gas detonation influence coefficient is calculated based on the torque detonation coefficient and its preset weighting coefficient, the excess air detonation coefficient and its preset weighting coefficient, and the integral detonation coefficient and its preset weighting coefficient.

8. The method for detecting gas composition in a natural gas engine according to claim 7, characterized in that, Methods for detecting the composition of natural gas engine gases also include: Based on the intake air temperature and water temperature, the preset weighting coefficients for the torque knock coefficient, the excess air knock coefficient, and the integral knock coefficient are determined.

9. A gas chemistry composition detection device for a natural gas engine, characterized in that, include: The acquisition module is used to acquire vibration signals from the combustion of natural gas engine cylinders; The adjustment module is used to adjust the natural gas engine to a preset gas quality detection point when the vibration signal is greater than or equal to a preset knock threshold, and to obtain the motor feedback torque, excess air coefficient and knock signal at the preset gas quality detection point. The calculation module is used to calculate the gas detonation influence coefficient based on the motor feedback torque, the excess air coefficient, and the detonation signal; The determination module is used to determine that the natural gas engine is detonated due to the influence of the gas composition when the gas composition detonation influence coefficient is greater than or equal to a preset threshold, so as to determine the gas composition difference of the natural gas engine.

10. A vehicle, characterized in that, include: Natural gas engine; The natural gas engine gas composition detection device as described in claim 9 above is communicatively connected to the natural gas engine.

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