A method for monitoring and regulating the entire link of fuel supply of ammonia engine

Abstract

The application discloses a kind of ammonia engine fuel supply full-link monitoring and regulation method, belong to internal combustion engine fuel supply and combustion control technical field.Through zero calibration and distributed ammonia / hydrogen concentration and temperature and pressure monitoring, realize pipeline safety monitoring and fault hierarchical positioning;Through parallel sampling pipeline and spectral analysis, construct cracking gas quality parameter A1 in combination with flow parameter;Through in-cylinder combustion signal and exhaust emission data inversion, respectively construct quality parameter A2, A3, fusion forms effective quality parameter B, realizes triple redundancy fault-tolerant monitoring;For five typical working conditions, two-way closed-loop regulation and control are carried out on electric heating power and ignition parameters based on parameter B.The application realizes fuel supply full-link safety control, component online monitoring and multi-condition combustion stability optimization.

Description

Technical Field

[0001] This invention relates to the technical field of fuel supply and combustion control for internal combustion engines, and particularly to a method for monitoring and regulating the entire fuel supply chain of an ammonia engine. Background Technology

[0002] Ammonia, as an emerging clean energy source, has become a key technological path for the zero-carbon transformation of the internal combustion engine field due to its advantages such as convenient storage and transportation, high energy density, and mature industrialization system. However, due to the characteristics of ammonia, such as high ignition energy, slow flame propagation speed, and narrow combustible range, direct combustion of ammonia is prone to problems such as poor combustion stability, large cycle fluctuations, and high unburned ammonia escape rate. Therefore, current mainstream technical solutions mostly adopt catalytic heating to crack ammonia into ammonia crack gas (mainly composed of hydrogen, nitrogen, and uncracked ammonia) before supplying it to the engine for combustion, thereby improving the combustion process of ammonia.

[0003] For ammonia engines, the ammonia cracking rate directly determines the proportions of hydrogen, ammonia, and nitrogen in the cracked gas, making it a core control parameter affecting engine performance. When the cracking rate is too high, the proportion of hydrogen in the cracked gas increases significantly, exacerbating the risk of engine pre-ignition and knocking, while also causing a sharp deterioration in NOx emissions during combustion. Conversely, when the cracking rate is too low, unburned ammonia emissions in the exhaust gas will increase substantially, leading to a series of problems such as poor fuel economy, decreased combustion stability, and increased cycle volatility. Multiple studies have shown that precisely matching the optimal cracking rate range to different operating conditions is essential to achieving a balance between the power, economy, and emission characteristics of ammonia engines.

[0004] However, existing technologies have the following shortcomings:

[0005] First, the monitoring dimensions are limited. Existing monitoring methods mainly involve setting up single-point component monitoring at the pyrolysis outlet or engine intake pipe of the ammonia cracking hydrogen production unit. This cannot achieve online monitoring of the components of the cracked gas throughout the entire transportation chain from the production end to the combustion end. It is difficult to accurately identify component deviations and gas leaks during pipeline transportation, and it is difficult to ensure the safety and stability during the development and testing of ammonia engines.

[0006] Second, there is a lack of coordinated control. Existing control strategies mostly focus on the closed-loop regulation of components in the ammonia cracking hydrogen production process, lacking coordinated control between the ammonia cracking hydrogen production system and the engine combustion system. This can easily lead to abnormal combustion phenomena such as in-cylinder combustion phase shift and misfire under transient operating conditions, ultimately resulting in a decrease in engine thermal efficiency and a surge in nitrogen oxide and unburned ammonia emissions.

[0007] Therefore, there is an urgent need to design a method for full-link monitoring and coordinated control of the fuel supply system for ammonia engine development and testing, in order to solve the problems of safety management, component monitoring and combustion stability under multiple operating conditions in the entire process of ammonia cracking gas supply. Summary of the Invention

[0008] The purpose of this section is to outline some aspects of embodiments of the present invention and to briefly describe some preferred embodiments. Simplifications or omissions may be made in this section, as well as in the abstract and title of this application, to avoid obscuring the purpose of these documents; however, such simplifications or omissions should not be construed as limiting the scope of the invention.

[0009] In view of the problems existing in the prior art, the present invention is proposed.

[0010] Therefore, the technical problem solved by this invention is that, to fully leverage the complementary advantages of ammonia's easy storage and transportation and hydrogen's excellent combustion performance, ammonia engines using ammonia cracking hydrogen production units have become an important direction for the development of high-efficiency, low-carbon engines. During the development and testing of ammonia engines, the cracked gas produced by the ammonia-to-hydrogen conversion unit is susceptible to problems such as component fluctuations, abnormal pressure, and gas leakage due to the influence of test conditions and environmental factors during production, storage, and transportation. Simultaneously, the lack of coordinated operation between the ammonia cracking hydrogen production system and the engine combustion system makes it difficult to dynamically match fuel supply with combustion demand, affecting engine combustion stability and the safety of development and testing.

[0011] To solve the above-mentioned technical problems, the present invention provides the following technical solution: a method for monitoring and controlling the entire fuel supply chain of an ammonia engine, comprising the following steps: Step 1, Zero-point calibration: When the ECU detects that the ammonia cracking hydrogen production unit has started preheating, the electromagnetic sampling valve and the recovery valve are closed, and the nitrogen valve is opened to allow nitrogen to flow from the nitrogen cylinder into the monitoring chamber of the intake component monitoring device. After the pressure and temperature of the chamber stabilize to the calibration condition, a static spectral baseline is collected to complete the zero-point adjustment; then the nitrogen valve is closed, the recovery valve is opened, and nitrogen is discharged into the cylinder through the pressure difference formed between the intake manifold and the recovery tank when the piston moves downward. After the recovery is completed, the recovery valve is closed; Step 2, Pipeline safety monitoring and fault location: The ammonia / hydrogen concentration α on the outside of the pipeline is collected by ammonia sensors and hydrogen sensors distributedly installed on the transport pipeline. x Temperature and pressure fluctuation amplitude β1 in the pipeline is monitored by temperature and pressure sensors installed at the outlet of the pyrolysis unit and the inlet of the pressure stabilizing tank, and temperature and pressure fluctuation amplitude β2 in the pipeline is monitored by temperature and pressure sensors installed at the inlet and outlet of the pressure stabilizing tank and the engine intake end, and α is... x α, β1, and β2 are transmitted to the ECU; the ECU performs classification and processing according to the following rules: when α x <0.01ppm and β x When the concentration is <0.01%, the pipeline is considered to have no leakage; when 0.01ppm < α x <5ppm and 0.01% <β x When α is <5%, a minor pipeline leak is identified, an early warning is issued, and the pyrolysis gas flow rate is reduced; when α x >5ppm and β x>5%, it is determined that the pipeline has a serious leakage, and the engine is shut down immediately; when α x <0.01ppm but β x >5%, it is determined that non-leakage loss of cracked gas occurs, and the opening of the pressure regulating valve is increased to compensate for the pipeline loss; Step 3. Monitoring of cracked gas components and calculation of quality parameter A1: Through symmetric parallel monitoring pipelines with the same pipe diameter, equal length and same material, synchronous electromagnetic sampling valves are used to perform micro-sampling of cracked gas at the outlet of the cracking unit and the gas inlet end, the difference in opening and closing timing is ≤1ms, and the sampling flow rate is no more than 0.5% of the rated flow rate of the main pipeline; the cracking rate η is obtained through the intake component monitoring device, combined with the bypass supply pipeline flow m 旁 and the main supply pipeline ammonia flow m NH3主 , the cracked gas quality parameter A1 is calculated:

[0012]

[0013] Step 4. Calculation of combustion and emission inversion quality parameters and construction of effective quality parameter B: The in-cylinder combustion signal is collected through the cylinder pressure sensor and the crankshaft position sensor, and the ignition delay period, CA50, peak heat release rate and peak phase are calculated to inversely obtain the cracked gas quality parameter A2; the combustion exhaust gas parameters are collected through the ammonia concentration sensor, NOx concentration sensor and exhaust gas temperature sensor in the exhaust pipeline to inversely obtain the cracked gas quality parameter A3; the three sets of data A1, A2 and A3 are compared with each other, if the deviation of one set of data from the other two sets exceeds 20%, it is determined that the corresponding monitoring unit is faulty and this set of data is shielded, and the remaining two sets of data are used to complete the control; for different working conditions, the effective quality parameter B of cracked gas is constructed according to the following weighting formula: Steady-state working condition: B1=0.45×A1+0.35×A2+0.2×A3; Transient working condition: B2=0.3×A1+0.5×A2+0.2×A3;

[0014] Step 5. Working condition identification and multi-working condition cooperative regulation: The ECU identifies the specific working condition of the engine according to the change rate of throttle opening, coolant temperature, intake air temperature, engine speed and speed change trend, and implements differentiated regulation according to the following rules: (1) Cold start working condition —— Taking B2 as the control parameter, only the first quarter area in front of the cracker is concentrated for electric heating and the ammonia flow rate is reduced, and the spark plug is controlled to perform secondary ignition; (2) Low-load steady-state working condition —— Taking B1 as the control parameter, 22%<B1<28% is set as the reasonable cracking rate range. When B1 exceeds this range, correction is performed by adjusting the electric heating power and the ignition advance angle. When B1 is within this range, the ignition advance angle is adjusted by comparing CA50 with the standard CA50 value k, and through COV IMEPCompare with 5% to adjust combustion stability; (3) Medium and high load steady-state working condition —— taking B1 as the control parameter, setting 20%<B1<25% as the reasonable cracking rate range, when B1 exceeds this range, correction is carried out by adjusting the electric heating power and ignition advance angle, and when B1>25%, the electric heating is cut off and only exhaust waste heat is used; (4) Rapid acceleration working condition —— taking B2 as the control parameter, setting 28%<B2<30% as the reasonable cracking rate range, the electric heating power is increased in advance and sufficient cracked gas is stored in the pressure stabilizing tank, and correction is carried out by adjusting the electric heating power and ignition advance angle; (5) Rapid deceleration working condition —— taking B2 as the control parameter, setting 18%<B2<22% as the reasonable cracking rate range, the electric heating is immediately disconnected and only exhaust waste heat is used, the ammonia flow is reduced to the minimum stable flow through the pressure regulating valve, and correction is carried out by adjusting the throttle opening, heating temperature and ignition advance angle.

[0015] As a preferred solution of the full-link monitoring and regulation method for ammonia engine fuel supply according to the present invention, wherein: in step 3, the components in the pipeline controlled by the electromagnetic sampling valve are further compared with the components in the pipeline controlled by the electromagnetic sampling valve, if the hydrogen content difference k ≤ 5%, the loss of cracked gas is determined to be negligible; if the hydrogen content difference k > 5%, the pipeline is determined to be blocked and needs to be replaced after the vehicle stops driving.

[0016] As a preferred solution of the full-link monitoring and regulation method for ammonia engine fuel supply according to the present invention, wherein: in step 3, the difference between the cracking rate η obtained by the ECU and the standard cracking rate calibrated on the bench is set as A0, and when |A0|>10%, the catalyst activity is determined to be greatly reduced and needs to be replaced.

[0017] As a preferred solution of the full-link monitoring and regulation method for ammonia engine fuel supply according to the present invention, wherein: before step 3, ammonia engine tests under different working conditions and different cracking rates are carried out first, three-dimensional simulation is performed on the in-cylinder mixture process of each test working condition, and the mixture quality evaluation coefficient Y = f(U, C, S) is constructed by combining the test results and the mixture distribution characteristics, where U is the mixture uniformity coefficient, C is the combustible mixture coverage, and S is the combustible mixture coverage near the spark plug; the mixture distribution is divided into three grades of excellent, good and poor according to the value of Y, and the ECU control MAP is collaboratively corrected by combining the evaluation results and the effective quality parameter B of the cracked gas, so as to form a multi-working-condition control logic suitable for different cracking rates.

[0018] As a preferred solution of the full-link monitoring and regulation method for ammonia engine fuel supply according to the present invention, wherein: in step 5 (1) cold start working condition, the preset temperature is obtained from the engine bench calibration test, and when both the coolant temperature and the intake air temperature are lower than the preset temperature, the working condition is determined as the cold start working condition.

[0019] As a preferred solution of the ammonia engine fuel supply full-link monitoring and regulation method according to the present invention, wherein: in the step 5 (2) low-load steady-state working condition, when 22%≤B1≤28%, if CA50>k, the ignition advance angle is increased, and if CA50<k, the ignition advance angle is decreased; if COV IMEP ≥5%, the ignition is advanced for suppression, then B1 is gradually increased and the ignition timing is delayed until COV IMEP <5%.

[0020] As a preferred solution of the ammonia engine fuel supply full-link monitoring and regulation method according to the present invention, wherein: in the step 5 (3) medium and high-load steady-state working condition, when 20%<B1<25%, if CA50>k, the ignition advance angle is increased, and if CA50<k, the ignition advance angle is decreased; if COV IMEP ≥5%, the ignition is advanced for suppression, then B1 is gradually increased and the ignition timing is delayed until COV IMEP <5%; when B1>25%, the ignition timing is appropriately delayed to avoid NOx exceeding the standard, then the electric heating is immediately cut off, only exhaust waste heat is used, and the electric heating is turned on again after B1 drops to within 25%.

[0021] As a preferred solution of the ammonia engine fuel supply full-link monitoring and regulation method according to the present invention, wherein: in the step 5 (4) rapid acceleration working condition, the ECU predicts that the engine is about to enter the rapid acceleration working condition according to the rising trend of the engine speed, pre-increases the electric heating power to the preset heating temperature and then increases the opening of the pressure regulating valve to match the large flow demand; when 28%≤B2≤30% and COV IMEP ≥5%, the ignition is advanced for suppression, then B2 is gradually increased and the ignition timing is coordinately regulated until COVIMEP<5%; when B2>30%, the ignition timing is delayed to reduce the knock risk, then the electric heating power is gradually decreased until B2 drops to within 30%.

[0022] As a preferred solution of the ammonia engine fuel supply full-link monitoring and regulation method according to the present invention, wherein: in the step 5 (5) rapid deceleration working condition, the ECU predicts that the engine is about to enter the rapid deceleration working condition according to the falling trend of the engine speed, immediately disconnects the electric heating and only uses exhaust waste heat, restarts the electric heating to stabilize the cracking rate after B2 rapidly drops to the range of 18% to 22%, and reduces the ammonia flow to the minimum stable flow through the pressure regulating valve; when B2<18%, the throttle valve is slightly opened to slightly increase the engine load to avoid a sharp drop of the exhaust temperature, then the heating temperature is increased until B2 rises to more than 18%; when 18%≤B2≤22% and COV IMEP ≥5%, the ignition is advanced for suppression, then B2 is gradually increased and the ignition timing is coordinately regulated until COV IMEP<5%; When B2>22%, delay the ignition timing to avoid a sudden drop in cylinder temperature, and then gradually reduce the heating temperature until B2 drops below 22%.

[0023] As a preferred embodiment of the ammonia engine fuel supply end-to-end monitoring and control method described in this invention, the component monitoring system consists of four parallel pipelines, with all sampling ports located at the same cross-section. The pipelines are designed to be of equal diameter, length, material, and flow resistance. The electromagnetic sampling valve is controlled by the ECU, with a start-up time difference of ≤1ms. The monitored gas flows into the recovery tank through the recovery valve, and then enters the intake passage through the pressure difference formed between the intake manifold and the recovery tank, thereby realizing the recycling of the sampled gas.

[0024] This invention provides a method for monitoring and controlling the entire fuel supply chain of an ammonia engine, which has the following beneficial effects:

[0025] 1. The quality parameters of pyrolysis gas can accurately reflect the true condition of the fuel entering the cylinder. This invention constructs a triple-redundant monitoring system for pyrolysis gas quality. Through the fusion and verification of multi-source information from three aspects—direct monitoring of intake components (A1), combustion performance inversion (A2), and emission data inversion (A3)—it accurately reflects the actual quality of the pyrolysis gas entering the cylinder, significantly improving monitoring accuracy and reliability, while avoiding combustion runaway caused by the failure of a single source monitoring. The three sets of data are cross-checked. When the deviation of one set of data from the other two sets exceeds 20%, the faulty data is automatically shielded and the remaining two sets of data are used to complete the control, achieving redundancy and fault tolerance.

[0026] 2. Enhanced safety during the ammonia engine development and testing process through end-to-end monitoring. This invention enables end-to-end parameter monitoring and anomaly identification during the ammonia engine development and testing process, from the liquid ammonia tank and ammonia cracking hydrogen production unit to the engine. Through the linkage of distributed ammonia / hydrogen sensors and temperature and pressure sensors, it accurately locates faulty pipelines and their severity (no leakage, minor leakage, severe leakage, pipeline loss), and provides graded response strategies (early warning to reduce flow, immediate shutdown, pressure compensation, etc.). Simultaneously, it monitors component loss during the transportation process in real time, providing a safe and stable fuel supply guarantee for the ammonia engine development and testing.

[0027] 3. The two-way closed-loop regulation method improves the system's combustion efficiency and adaptability to various operating conditions. This invention uses the effective quality parameter B of the cracked gas as a benchmark, and adapts the engine combustion strategy (ignition advance angle, spark plug secondary ignition, etc.) in real time based on its changes. Simultaneously, it corrects the operating parameters of the ammonia cracking hydrogen production unit (electric heating power, ammonia flow rate, pressure regulating valve opening, etc.) based on feedback from engine combustion and emission parameters, achieving precise matching of cracking efficiency and combustion performance under all operating conditions. Differentiated control strategies and reasonable cracking rate ranges are designed for five typical operating conditions: cold start, low-load steady state, medium-high-load steady state, rapid acceleration, and rapid deceleration, significantly improving the combustion stability and performance of the ammonia engine under various operating conditions. Attached Figure Description

[0028] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. Wherein:

[0029] Figure 1 This is a typical gas-mixture equivalent ratio distribution cloud map of the present invention (a comparative diagram of superior, good, and inferior products).

[0030] Figure 2 This is a schematic diagram of the end-to-end monitoring system for an ammonia cracking hydrogen production unit for an ammonia engine, as described in this invention.

[0031] Figure 3 This is the control logic diagram for low-load operating conditions of the present invention;

[0032] Figure 4 This is the control logic diagram for high-load conditions in this invention;

[0033] Figure 5 This is the control logic diagram for the rapid acceleration condition of this invention;

[0034] Figure 6 This is the control logic diagram for the rapid deceleration condition of this invention.

[0035] The components include: 1. Ammonia conversion hydrogen production unit; 2. Check valve; 3. Temperature and pressure sensor; 4. Ammonia concentration sensor; 5. Hydrogen concentration sensor; 6. Temperature and pressure sensor; 7. Check valve; 8. Pressure stabilizing tank; 9. ECU; 10. Check valve; 11. Temperature and pressure sensor; 12. Ammonia concentration sensor; 13. Flow meter; 14. Throttle position sensor; 15. Hydrogen concentration sensor; 16. Temperature and pressure sensor; 17. Check valve; 18. Recovery valve; 19. Cylinder pressure sensor; 20. Spark plug; 21. Exhaust temperature sensor; 22. NOx sensor; 23. Ammonia concentration sensor; 24. 25. Hydrogen concentration sensor; 26. Ammonia valve; 27. Ammonia flow meter; 28. Electromagnetic sampling valve; 29. ​​Electromagnetic sampling valve; 30. Electromagnetic sampling valve; 31. Ammonia valve; 32. Hydrogen nozzle; 33. Evaporator; 34. Nitrogen valve; 35. Nitrogen valve; 36. Nitrogen valve; 37. Nitrogen valve; 38. Pressure reducing valve; 39. Ammonia concentration sensor; 40. Inlet gas component monitoring device; 41. Nitrogen cylinder; 42. Inlet gas component monitoring device; 43. Liquid ammonia tank; 44. Recovery valve; 45. Recovery tank; 46. Recovery valve; 47. Recovery valve; 48. Speed ​​sensor. Detailed Implementation

[0036] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of the present invention.

[0037] To address the problems existing in the prior art, this invention proposes a method for full-link monitoring and coordinated control of the fuel supply system for ammonia engine development and testing. This method aims to solve the shortcomings of lack of safety control and insufficient online component monitoring in the entire ammonia cracking gas supply process, optimize the combustion process of the ammonia engine, and provide a more complete ammonia engine calibration scheme.

[0038] Specifically, by monitoring the pipeline status and coupling engine combustion and emission signals, accurate monitoring of pyrolysis gas quality and stable combustion under multiple operating conditions can be achieved while ensuring the safety and controllability of the gas supply process.

[0039] (I) Main structural diagram:

[0040] In the development and testing of ammonia engines, the corresponding cracked gas components are typically matched based on the target cracking rate to conduct engine calibration and performance development tests under different cracking rate conditions. As the cracking rate changes, the proportions of hydrogen, ammonia, and nitrogen in the cracked gas change, leading to differences in the in-cylinder mixture distribution. Existing ECU control MAPs are usually calibrated based on the fuel components corresponding to a preset cracking rate, lacking dynamic correction for changes and distribution in the mixture components, making it difficult to achieve precise matching between fuel supply and engine control parameters. Therefore, ammonia engine tests were conducted under different operating conditions and cracking rates. Three-dimensional simulations of the in-cylinder mixture process under each test condition were performed. Combining the test results with the mixture distribution characteristics, a mixture quality evaluation system was constructed, setting the mixture quality evaluation coefficient Y=f(U, C, S), where U represents the mixture uniformity coefficient, C represents the combustible mixture coverage, and S represents the combustible mixture coverage near the spark plug. Based on the magnitude of Y, the mixture distribution was divided into three grades: excellent, good, and poor, and a mixture equivalence ratio distribution cloud map was selected as a typical representation of each grade. Figure 1 As shown, a high-quality combustible mixture forms good stratification, creating a continuous and suitable combustible zone near the spark plug; a good-quality mixture has a relatively uniform overall distribution, but the rich mixture zone deviates to some extent from the spark plug area; a poor-quality mixture exhibits localized over-rich or over-lean phenomena, with insufficient combustible mixture near the spark plug and poor combustion stability. Based on the above mixture quality evaluation results, the ECU control MAP is collaboratively corrected in conjunction with the effective quality parameters of the pyrolysis gas, forming a multi-condition control logic suitable for different pyrolysis rates.

[0041] Based on the above, this invention proposes a method for end-to-end monitoring and coordinated control of a fuel supply system for ammonia engine development and testing. The main components include a liquid ammonia tank, an ammonia-to-hydrogen conversion unit, an engine body, and an ECU, as shown in the structural diagram below. Figure 2 As shown.

[0042] Figure 2 Liquid ammonia flows out from liquid ammonia tank 43, passes through pressure reducing valve 38 and enters evaporator 33. After being converted into ammonia gas, it enters the cylinder through the main supply line, ammonia valve 25, ammonia flow meter 26, and ammonia valve 31. The ammonia flow rate m of the main supply line is measured. NH3主 Ammonia gas supplied via the bypass line enters the ammonia conversion hydrogen production unit 1, then flows into the pressure stabilizing tank through check valves 2 and 7. After the pressure stabilizes, it is injected into the cylinder through check valve 10, flow meter 13, and check valve 17. The bypass line flow rate m is measured. 旁The component monitoring system consists of four parallel pipelines, all with sampling ports located at the same cross-section. The pipelines are designed with identical diameter, length, material, and flow resistance. Electromagnetic sampling valves 27, 28, 29, and 30 are controlled by ECU9, with a start-up time difference ≤1ms to ensure no external interference. The sampled gas is monitored in the inlet component monitoring devices 40 and 42, and the results are transmitted to ECU9 to obtain the cracking rate η, combined with m... 旁 m NH3主 The quality parameter A1 of the cracked gas is obtained. The monitored gas flows into the recovery tank 45 through recovery valves 44 and 47, and then enters the intake duct through recovery valves 46 and 18 through the pressure difference formed between the intake manifold and the recovery tank.

[0043] The monitoring and zeroing system is achieved through a combination of nitrogen cylinder 41 and a monitoring gas recovery system. High-purity nitrogen flows from nitrogen cylinder 41 into the monitoring chambers of the intake component monitoring devices 40 and 42 via nitrogen valves 34, 35, 36, and 37, respectively, while recovery valves 44 and 47 are closed for zeroing. After zeroing is completed, recovery valves 44, 46, 47, and 18 are opened to release the nitrogen into the cylinder.

[0044] A speed sensor 48 is installed at the engine crankshaft to measure the real-time engine speed. A throttle position sensor 14 monitors changes in throttle opening, and these changes, combined with the speed changes, determine the operating conditions of the ammonia engine. Cylinder pressure sensors 19 are installed inside the engine cylinders to monitor pressure changes during the engine combustion process in real time. The ignition delay period, CA50, and peak and peak phase of the heat release rate are then calculated in the ECU9 to obtain the cracked gas quality parameter A2.

[0045] Combustion exhaust gas is discharged through the exhaust duct and passes through exhaust temperature sensor 21, NOx sensor 22, and ammonia concentration sensor 23 to measure the unburned ammonia concentration, NOx emission concentration, and exhaust temperature. These measurements are then transmitted to ECU9 to obtain the pyrolysis gas quality parameter A3. Based on the operating conditions, ECU9 combines A1, A2, and A3 to obtain the effective pyrolysis gas quality parameter B. Detailed Implementation Plan

[0046] This invention proposes a method for end-to-end monitoring and coordinated control of an ammonia cracking hydrogen production unit for ammonia engines, the specific implementation of which is as follows:

[0047] Step 1: When the ECU detects that the ammonia cracking hydrogen production unit has started preheating, it closes the electromagnetic sampling valve and the recovery valve, and opens the nitrogen valve. Nitrogen gas is introduced from the nitrogen cylinder into the monitoring chamber of the intake component monitoring device. After the pressure and temperature of the chamber stabilize to the calibration conditions, a static spectral baseline is acquired to complete the zero-point adjustment. Subsequently, the nitrogen valve is closed and the recovery valve is opened. Nitrogen gas is discharged into the cylinder through the pressure difference formed between the intake manifold and the recovery tank when the piston moves downward. After the recovery is completed, the recovery valve is closed.

[0048] Step Two: Ammonia and hydrogen concentrations outside the pipeline are collected using distributed ammonia and hydrogen sensors, recorded as α1, α2, α3, α4, α5, and α6 respectively, and transmitted to the ECU. Temperature and pressure fluctuations within the pipeline are monitored using temperature and pressure sensors installed at the pyrolysis unit outlet and the pressurized tank inlet, recorded as β1. Temperature and pressure fluctuations within the pipeline are monitored using temperature and pressure sensors installed at the pressurized tank inlet and outlet and at the engine intake, recorded as β2, and β1 and β2 are transmitted to the ECU. When the ammonia / hydrogen concentration outside the pipeline α... x <0.01ppm and temperature and pressure fluctuation range β x If the concentration is <0.01%, it is determined that there is no leak in the pipeline; if the concentration outside the pipeline is 0.01ppm < α, it is considered that there is no leak. x <5ppm and 0.01% <β x If the concentration is <5%, it is determined that there is a minor leak in the pipeline. An immediate warning is issued, and the pyrolysis gas flow rate is reduced. After the vehicle stops running, the concentration of pyrolysis gas below 0.01 ppm is adjusted. x Replace the tubing if the concentration is <5ppm; when α x >5ppm and β x If the leakage rate is greater than 5%, it is determined that there is a leak in the pipeline, and the engine should be stopped immediately. For α... x Replace the tubing if the concentration is >5 ppm; when α x <0.01ppm but β x If the pressure is greater than 5%, it is determined that the pyrolysis gas has been lost during transportation. The ECU is then used to increase the opening of the pressure regulating valve to compensate for pipeline losses and ensure that the engine intake pressure meets requirements. After the vehicle stops, β... x >5% of the pipelines were inspected and maintained.

[0049] Step 3: Ensuring the safety of the transport pipeline, monitor the components at the outlet and inlet of the pyrolysis unit using symmetrical parallel monitoring pipelines of the same diameter, length, and material. Micro-samples of the pyrolysis gas composition are taken using synchronous electromagnetic sampling valves, with an opening / closing timing difference ≤1ms. The sampling flow rate must not exceed 0.5% of the main line's rated flow rate to avoid affecting the stability of the main line flow and the uniformity of the intake. After the gas flows into the monitoring chamber, the pyrolysis gas components are monitored using the intake component monitoring device. The components of the pipelines controlled by electromagnetic sampling valves 27 and 28, and 29 and 30 are compared separately. If the hydrogen content difference k ≤ 5%, it indicates that the loss of pyrolysis gas during the process from the pyrolysis unit to the pressure stabilizing tank is negligible; if the hydrogen content difference k > 5%, it indicates that there is loss of pyrolysis gas during the process from the pyrolysis unit to the pressure stabilizing tank, and the pipeline may be blocked, requiring replacement after the operation is completed. The standard pyrolysis rate of the ammonia engine is calibrated through testing. The difference between the cracking rate η obtained from the ECU and the standard cracking rate is set as A0. When |A0|>10%, the catalyst activity is considered to be significantly reduced and needs to be replaced. The bypass flow rate m is obtained through flow meter 13. 旁 m is calculated and obtained in the ECU. NH3旁 and m H2 Obtain the cracked gas quality parameter A1 from the ECU;

[0050]

[0051] Step 4: The corresponding MAP libraries for ignition delay period, CA50, peak heat release rate, peak phase, and cracking rate under different operating conditions have been calibrated through engine bench testing. In-cylinder combustion signals are collected using cylinder pressure sensor 19 and crankshaft position sensor 48 and transmitted to ECU9. The corresponding cycle's ignition delay period, CA50, peak heat release rate, and peak phase are calculated, and the actual cracked gas quality parameter A2 is obtained through inversion. The corresponding MAP libraries for unburned ammonia concentration, NOx emission concentration, exhaust temperature, and cracking rate under different operating conditions have been calibrated through engine bench testing. In-cylinder combustion signals are collected using ammonia concentration sensor 23, NOx concentration sensor 22, and exhaust temperature sensor 21 in the exhaust pipe and transmitted to ECU9. Compared with the calibrated MAPs, the cracked gas quality parameter A3 is obtained through inversion. Effective cracked gas quality parameters B are constructed for different operating conditions. Under steady-state conditions, combustion is relatively stable, and pipeline monitoring plays a dominant role, with B1 = 0.45*A1 + 0.35*A2 + 0.2*A3. Under transient conditions, combustion fluctuates significantly, and combustion inversion results dominate, with B2 = 0.3*A1 + 0.5*A2 + 0.2*A3. The three sets of data are compared. If the deviation of one set of data from the other two sets exceeds 20%, the monitoring unit is considered faulty, the faulty data is masked, and the remaining two sets of data are used for control, achieving redundancy and fault tolerance.

[0052] Step 5: Compare the measured coolant temperature and intake air temperature with the preset temperature. The preset temperature is obtained from engine bench calibration tests. If both the coolant temperature and the intake air temperature are lower than the preset temperature, it is determined that the current operating condition is a cold start condition. At this time, the operating condition is in a transient condition, and the effective quality parameter of cracked gas is taken as B2. Under the cold start condition, the initial temperatures in the cylinder and the cracker are relatively low, while pure ammonia requires a high ignition energy, which makes the engine extremely prone to misfire and leads to excessive unburned ammonia content. Under the cold start condition, the ammonia cracking hydrogen production device only uses electric heating to centrally heat the first quarter area of the cracker, so that it quickly reaches the cracking temperature, and simultaneously reduces the ammonia flow rate to ensure sufficient heating time, so that ammonia is cracked into a sufficient amount of hydrogen. At the same time, the spark plug is controlled to perform secondary ignition to ensure the smooth start of the ammonia engine.

[0053] Step 6: Monitor the engine throttle opening and rotational speed through the throttle position sensor and the rotational speed sensor, and compare them with the preset ranges in the ECU. If the change rate of the throttle opening is low, it is determined that the current operating condition is a steady-state operating condition, and the quality parameter of cracked gas is taken as B1. If the throttle opening and the rotational speed at this time meet the preset numerical range for low load, it is determined that the engine is currently in a low-load operating condition. The preset numerical range for the low-load operating condition is calibrated through engine bench tests. Under the low-load operating condition, the in-cylinder temperature is relatively low, and a relatively high amount of hydrogen is required to ensure stable combustion, so 22% < B1 < 28% is set as the reasonable cracking rate range. When B1 < 22%, the proportion of hydrogen used for ignition is insufficient, the electric heating power is immediately increased, and the ignition is advanced at the same time to offset the long ignition delay period of ammonia, until B1 rises to above 22%. When 22% < B1 < 28%, CA50 and COV IMEP are compared with the target values. Let the standard CA50 value be k. If CA50 > k, it proves that the combustion is too slow, and the ignition advance angle is increased; if CA50 < k, it proves that the combustion is too fast, and the ignition advance angle is decreased. The combustion stability of the ammonia engine is ensured by COV IMEP . If COV IMEP is less than 5%, it proves that the combustion is stable and no regulation is needed; if COV IMEP is greater than 5%, it proves that the combustion is unstable, the ignition is immediately moderately advanced for suppression, then the cracking rate B1 is gradually increased, and the ignition timing is delayed until the combustion is stable. When B1 > 28%, the proportion of hydrogen in the mixture is relatively high, the in-cylinder temperature is relatively high, and NOx emissions increase significantly. The electric heating power is immediately reduced until B1 drops to within 28%.

[0054] Step 7: The engine throttle opening and rotational speed are monitored through the throttle position sensor and the photoelectric sensor at the crankshaft, and are compared with the preset ranges in the ECU. If the rate of change of the throttle opening is low, it is determined that the operating condition at this time is a steady-state operating condition, and the cracked gas quality parameter is set to B1. If the throttle opening and rotational speed at this time conform to the preset numerical ranges for medium and high loads, it is determined that the engine is currently in a medium and high load operating condition. The preset numerical ranges for medium and high load operating conditions are calibrated through engine bench tests. Under medium and high load operating conditions, the in-cylinder temperature and pressure are relatively high, the combustion speed of ammonia increases significantly, but NOx emissions surge at this time, so 20% < B1 < 25% is set as the reasonable cracking rate range. When B1 < 20%, the proportion of hydrogen used for ignition is insufficient, the electric heating power is immediately increased, and the ignition is advanced at the same time to match the combustion characteristics under the low hydrogen proportion, until B1 rises above 20%. When 20% < B1 < 25%, CA50 and COV IMEP are compared with the target values. Let the standard CA50 value be k; if CA50 > k, it indicates that the combustion is too slow, and the ignition advance angle is increased; if CA50 < k, it indicates that the combustion is too fast, and the ignition advance angle is decreased. If COV IMEP is less than 5%, it indicates that the combustion is stable and no regulation is required; if COV IMEP is greater than 5%, it indicates that the combustion is unstable, the ignition is immediately moderately advanced for suppression, then the cracked gas quality parameter B1 is gradually increased, and the ignition timing is delayed until the combustion is stable. When B1 > 25%, the risk of engine knock increases significantly, the ignition timing is moderately delayed to avoid excessive NOx, then the electric heating is immediately cut off, only exhaust waste heat is used, and the electric heating is turned on again after the cracking rate drops to within 25%.

[0055] Step 8: The throttle opening and engine rotational speed are monitored through the throttle position sensor and the photoelectric sensor at the crankshaft. If the rate of change of the throttle opening is extremely high, it is determined that the operating condition at this time is a transient operating condition, and the effective cracked gas quality parameter is set to B2. The engine rotational speed shows an upward trend, and it is predicted that the engine is about to enter a rapid acceleration operating condition. During the rapid acceleration process, the intake air amount and fuel amount increase sharply, the in-cylinder operating condition changes drastically, and there is a 1-2s lag in the ammonia cracking reaction, which very easily leads to the cracking rate failing to keep up with the fuel demand, insufficient hydrogen proportion, and thus combustion deterioration. Therefore, 28% < B2 < 30% is set as the reasonable cracking rate range. After the ECU determines that the engine has entered the rapid acceleration operating condition, the electric heating power is increased in advance; after reaching the preset heating temperature, the pressure regulating valve is enlarged to match the large flow demand required for rapid acceleration, and a sufficient amount of cracked gas that meets the requirements is stored in the pressure stabilizing tank. When B2 < 28%, the electric heating power is increased, and the ignition is moderately advanced at the same time, until the cracking rate rises above 28%. When 28% < B1 < 30%, COV IMEP is compared with the target value. If COV IMEP is less than 5%, it indicates that the combustion is stable during the rapid acceleration process and no regulation is required; if COVIMEP If it is greater than 5%, it indicates unstable combustion, ignition will be moderately advanced immediately for suppression, then the quality parameter B2 of the cracked gas is gradually increased, and the ignition timing is coordinately regulated until the combustion is stable. When B2>30%, the ignition timing is moderately retarded to reduce the risk of engine knock. Then, the electric heating power is gradually reduced until the cracking rate drops to within 30%.

[0056] Step 9: The throttle opening and the engine speed are monitored through the throttle position sensor and the photoelectric sensor at the crankshaft. If the change rate of the throttle opening is extremely high, it is determined that the working condition is in a transient working condition at this time, and the effective quality parameter of the cracked gas is taken as B2. The engine speed shows a downward trend, and it is predicted that the engine is about to enter a rapid deceleration working condition. During the rapid deceleration process, the engine intake volume drops sharply, and the in-cylinder temperature decreases rapidly, which is very prone to excessive cracked gas and excessive unburned ammonia emissions. Therefore, 18%<B2<22% is set as a reasonable cracking rate range. Under the rapid deceleration working condition, the electric heating is disconnected immediately, only the waste heat of exhaust gas is used, the electric heating is restarted after the cracking rate is rapidly reduced to the range, and the cracking rate is stabilized within the specified range, then the ammonia flow rate is reduced to the minimum stable flow rate through the pressure regulating valve to avoid a large amount of ammonia escape. When B2<18%, the throttle is slightly opened moderately to increase the engine load slightly, so as to avoid a sharp drop in exhaust temperature. Then the heating temperature is increased until the cracking rate rises to more than 18%. When 18%<B1<22%, the COV IMEP is compared with the target value. If COV IMEP is less than 5%, it proves that the combustion is stable during the rapid acceleration process, and no regulation is required; if COV IMEP is greater than 5%, it indicates unstable combustion, ignition will be moderately advanced immediately for suppression, then the quality parameter B2 of the cracked gas is gradually increased, and the ignition timing is coordinately regulated until the combustion is stable. When B2>22%, the ignition timing is moderately retarded to avoid a sharp drop in in-cylinder temperature. Then, the heating temperature is gradually reduced until the cracking rate drops to within 22%.

[0057] The present invention has the following beneficial effects:

[0058] 1. Quality parameter of cracked gas: A triple redundant monitoring system for cracked gas quality is constructed, which truly reflects the actual quality of the cracked gas entering the cylinder through integrated verification of intake section monitoring, combustion performance inversion and emission data, greatly improving the monitoring accuracy and reliability, and avoiding combustion runaway caused by the failure of single-source monitoring at the same time;

[0059] 2. Full-process monitoring of the cracked gas delivery link: The full-process parameter monitoring and abnormality identification from the liquid ammonia tank, the ammonia cracking hydrogen production device to the engine during the development test of the ammonia engine are realized. Through the linkage of various sensors, the faulty pipeline is accurately located, and the component loss during the delivery process is monitored in real time, so as to provide a safe and stable fuel supply guarantee for the development test of the ammonia engine;

[0060] 3. Ammonia Conversion Hydrogen Production Unit-Engine Two-Way Closed-Loop Coordinated Control Method: Based on the quality parameters of the cracked gas, the engine combustion strategy is adapted in real time according to its changes. At the same time, the operating parameters of the ammonia cracking hydrogen production unit are corrected based on the feedback of the engine combustion parameters, thus achieving precise matching of cracking efficiency and combustion performance under all operating conditions.

[0061] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A method for monitoring and controlling the entire fuel supply chain of an ammonia engine, characterized in that, comprising the following steps: Step 1, zero point calibration: When the ECU (9) monitors that the ammonia cracking hydrogen production device (1) starts preheating, close the electromagnetic sampling valves (27), (28), (29), (30) and the recovery valves (44), (46), (47), (18), open the nitrogen valves (34), (35), (36), (37) to introduce nitrogen from the nitrogen cylinder (41) into the monitoring gas chambers of the intake component monitoring devices (40), (42), collect the static spectral baseline after the pressure and temperature of the gas chambers stabilize to the calibrated working condition to complete zero point adjustment; then close the nitrogen valves, open the recovery valves, discharge the nitrogen into the cylinder through the pressure difference formed between the intake manifold and the recovery tank (45) when the piston moves downward, and close the recovery valves after the recovery is completed; Step 2: Pipeline safety monitoring and fault location: Ammonia / hydrogen concentration α is collected from the outside of the pipeline using ammonia and hydrogen sensors distributedly installed on the transport pipeline. x Temperature and pressure fluctuation amplitude β1 in the pipeline is monitored by temperature and pressure sensors installed at the outlet of the pyrolysis unit and the inlet of the pressure stabilizing tank, and temperature and pressure fluctuation amplitude β2 in the pipeline is monitored by temperature and pressure sensors installed at the inlet and outlet of the pressure stabilizing tank and the engine intake end, and α is... x β1 and β2 are transmitted to ECU (9); ECU (9) performs classification and handling according to the following rules: When α x <0.01ppm and β x When the concentration is <0.01%, the pipeline is considered to have no leakage; when 0.01ppm < α x <5ppm and 0.01% <β x When α is <5%, a minor pipeline leak is identified, an early warning is issued, and the pyrolysis gas flow rate is reduced; when α x >5ppm and β x When α > 5%, a serious pipeline leak is determined, and the engine must be shut down immediately; when α x <0.01ppm but β x When the value is >5%, it is determined that there is a non-leakage loss of the cracked gas, and the opening of the pressure regulating valve is increased to compensate for the pipeline loss. Step 3, Monitoring of cracked gas components and calculation of quality parameter A1: Using symmetrical parallel monitoring pipelines of the same diameter, length and material, a small amount of cracked gas is sampled at the outlet and inlet of the cracking unit using a synchronous electromagnetic sampling valve. The opening and closing timing difference is ≤1ms, and the sampling flow rate is not greater than 0.5% of the rated flow rate of the main line. The cracking rate η is obtained through the inlet component monitoring devices (40) and (42), combined with the bypass supply flow rate m 旁 and the main supply ammonia flow rate (m) NH3主 Calculate the quality parameter A1 of the pyrolysis gas: ； Step 4, calculation of combustion and emission inversion quality parameters and construction of effective quality parameter B: collect in-cylinder combustion signals through the cylinder pressure sensor (19) and the crankshaft position sensor (48), calculate the ignition delay period, CA50, peak heat release rate and peak phase, and invert to obtain the cracked gas quality parameter A2; collect combustion exhaust gas parameters through the ammonia concentration sensor (23), NOx concentration sensor (22) and exhaust gas temperature sensor (21) in the exhaust pipeline, and invert to obtain the cracked gas quality parameter A3; compare the three sets of data A1, A2 and A3 with each other, if the deviation of a certain set of data from the other two sets exceeds 20%, the corresponding monitoring unit is judged to be faulty and this set of data is shielded, and the remaining two sets of data are used to complete the control; for different working conditions, the cracked gas effective quality parameter B is constructed according to the following weighting formula: Steady-state working condition: B1=0.45×A1+0.35×A2+0.2×A3; Transient working condition: B2=0.3×A1+0.5×A2+0.2×A3; Step 5, working condition identification and multi-working condition coordinated regulation: The ECU (9) identifies the specific working condition of the engine according to the change rate of throttle opening, coolant temperature, intake air temperature, engine speed and speed change trend, and implements differentiated regulation according to the following rules: (1) Cold start working condition — taking B2 as the control parameter, perform centralized electric heating only on the first quarter area in front of the cracker and reduce the ammonia flow rate, and control the spark plug (20) to perform secondary ignition; (2) Low-load steady-state working condition —— taking B1 as the control parameter, setting 22% < B1 < 28% as the reasonable cracking rate range, when B1 exceeds this range, correction is performed by adjusting the electric heating power and ignition advance angle; when B1 is within this range, the ignition advance angle is adjusted by comparing CA50 with the standard CA50 value k, and by means of COV IMEP which is compared with 5% to adjust combustion stability; (3) Medium and high load steady-state working condition — taking B1 as the control parameter, set 20%<B1<25% as the reasonable cracking rate range, when B1 exceeds this range, perform correction by adjusting the electric heating power and ignition advance angle, and when B1>25%, cut off the electric heating and only use exhaust waste heat; (4) Rapid acceleration working condition — taking B2 as the control parameter, set 28%<B2<30% as the reasonable cracking rate range, increase the electric heating power in advance and store a sufficient amount of cracked gas in the pressure stabilizing tank (8), and perform correction by adjusting the electric heating power and ignition advance angle; (5) Rapid deceleration working condition — taking B2 as the control parameter, set 18%<B2<22% as the reasonable cracking rate range, immediately disconnect the electric heating and only use exhaust waste heat, reduce the ammonia flow to the minimum stable flow through the pressure regulating valve, and perform correction by adjusting the throttle opening, heating temperature and ignition advance angle.

2. The method for monitoring and controlling the entire fuel supply chain of an ammonia engine according to claim 1, characterized in that, In step three, the components of the pipeline controlled by electromagnetic sampling valves (27) and (28) are compared with those controlled by electromagnetic sampling valves (29) and (30). If the difference in hydrogen content k ≤ 5%, the loss of cracked gas is negligible; if the difference in hydrogen content k > 5%, the pipeline is blocked and needs to be replaced after the trip.

3. The method for monitoring and controlling the entire fuel supply chain of an ammonia engine according to claim 2, characterized in that, In step three, the difference between the cracking rate η obtained by ECU (9) and the standard cracking rate calibrated on the bench is set as A0. When |A0|>10%, it is determined that the catalyst activity has been greatly reduced and needs to be replaced.

4. The method for monitoring and controlling the entire fuel supply chain of an ammonia engine according to claim 3, characterized in that, Before step three, ammonia engine tests under different operating conditions and different pyrolysis rates are conducted. The in-cylinder mixture process under each test condition is simulated in three dimensions. The mixture quality evaluation coefficient Y = f(U, C, S) is constructed by combining the test results and mixture distribution characteristics, where U is the mixture uniformity coefficient, C is the combustible mixture coverage, and S is the combustible mixture coverage near the spark plug. The mixture distribution is divided into three grades: excellent, good, and poor based on the value of Y. Based on this evaluation result and the effective quality parameter B of the pyrolysis gas, the ECU control MAP is collaboratively corrected to form a multi-condition control logic suitable for different pyrolysis rates.

5. The method for monitoring and controlling the entire fuel supply chain of an ammonia engine according to claim 4, characterized in that, Step 5 (1) In the cold start condition, the preset temperature is obtained from the engine bench calibration test. When both the coolant temperature and the intake air temperature are lower than the preset temperature, it is determined to be a cold start condition.

6. The method for monitoring and controlling the entire fuel supply chain of an ammonia engine according to claim 5, characterized in that, Step 5 (2) In the low-load steady-state operating condition, when 22%≤B1≤28%, if CA50>k, the ignition advance angle is increased; if CA50<k, the ignition advance angle is decreased; if COV IMEP ≥5%, the ignition is advanced for suppression, then B1 is gradually increased and the ignition timing is retarded until COV IMEP <5%.

7. The method for monitoring and controlling the entire fuel supply chain of an ammonia engine according to claim 6, characterized in that, In the high-load steady-state operating condition in Step 5 (3), when 20%<B1<25%, if CA50>k, the ignition advance angle is increased; if CA50<k, the ignition advance angle is decreased; if COV IMEP ≥5%, the ignition is advanced for suppression, then B1 is gradually increased and the ignition timing is delayed until COV IMEP <5%; when B1>25%, the ignition timing is moderately delayed to avoid excessive NOx emission, then the electric heating is immediately cut off, only exhaust waste heat is used, and the electric heating is turned on again after B1 drops to within 25%.

8. The method for monitoring and controlling the entire fuel supply chain of an ammonia engine according to claim 7, characterized in that, Step 5 (4) During rapid acceleration, the ECU (9) predicts that the engine speed is about to enter a rapid acceleration condition based on the upward trend of the engine speed. It increases the electric heating power to the preset heating temperature in advance and then increases the opening of the pressure regulating valve to match the large flow demand; when 28%≤B2≤30% and COV IMEP When the concentration is ≥5%, pre-ignition is used to suppress it, followed by gradually increasing B2 and coordinating the ignition timing until COV reaches 100%. IMEP <5%; When B2>30%, delay the ignition time to reduce the risk of knocking, and then gradually reduce the electric heating power until B2 drops below 30%.

9. The method for monitoring and controlling the entire fuel supply chain of an ammonia engine according to claim 8, characterized in that, In step five (5) during rapid deceleration, the ECU (9) predicts that the engine speed is about to enter a rapid deceleration condition based on the downward trend of the engine speed. It immediately disconnects the electric heating and uses only the waste heat of the exhaust gas. After B2 drops rapidly to the range of 18% to 22%, it restarts the electric heating to stabilize the cracking rate and reduces the ammonia flow rate to the minimum stable flow rate through the pressure regulating valve. When B2 < 18%, the throttle valve is slightly opened to increase the engine load slightly to avoid a sudden drop in exhaust temperature. Then the heating temperature is increased until B2 rises to above 18%. When 18% ≤ B2 ≤ 22% and COV IMEP When the concentration is ≥5%, pre-ignition is used to suppress it, followed by gradually increasing B2 and coordinating the ignition timing until COV reaches 100%. IMEP <5%; When B2>22%, delay the ignition timing to avoid a sudden drop in cylinder temperature, and then gradually reduce the heating temperature until B2 drops below 22%.

10. The method for monitoring and controlling the entire fuel supply chain of an ammonia engine according to claim 9, characterized in that, The component monitoring system consists of four parallel pipelines, with all sampling ports located at the same cross-section. The pipelines are designed to be of equal diameter, length, material, and flow resistance. The electromagnetic sampling valves (27), (28), (29), and (30) are controlled by the ECU (9), with a start-up time difference of ≤1ms. The monitored gas flows into the recovery tank (45) through the recovery valves (44) and (47), and then enters the intake passage through the pressure difference formed between the intake manifold and the recovery tank via the recovery valves (46) and (18), thus realizing the recycling of the sampled gas.

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