Hydrogen fuel supply method, system and combustion assembly therefor for internal combustion engines

Abstract

The present application aims to provide a hydrogen fuel supply method for an internal combustion engine, a system and a combustion assembly thereof, wherein the combustion assembly comprises a combustion chamber, an air intake passage, an exhaust passage, a first gas injection unit, a second gas injection unit and a pilot fuel injection unit. The air intake passage is in communication with the combustion chamber and is provided with an air intake valve between the air intake passage and the combustion chamber, the exhaust passage is in communication with the combustion chamber and is provided with an exhaust valve between the exhaust passage and the combustion chamber, the first gas injection unit has a first nozzle which is arranged to extend into the air intake passage, the second gas injection unit has a second nozzle which is arranged to extend into the combustion chamber, and the pilot fuel injection unit has a fuel nozzle which is arranged to extend into the combustion chamber. Through the combustion assembly, stable operation of the hydrogen internal combustion engine can be realized under the premise of ensuring the performance of the hydrogen internal combustion engine.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of internal combustion engines, and in particular to a hydrogen fuel supply method and system for an internal combustion engine and a combustion assembly thereof. BACKGROUND

[0002] In order to control greenhouse gas emissions and establish a sound green and low-carbon circular development economic system, the community has made commitments to reduce carbon dioxide emissions. These goals have placed more explicit and stringent requirements on future energy structures. Fuel low-carbonization or even zero-carbonization is an inevitable trend in future energy development.

[0003] The research, development and utilization of alternative fuels for ships, especially low-carbon and zero-carbon fuels, are of great significance at present. On the one hand, it can break away from the dependence on traditional petrochemical fuels and avoid energy shortages. On the other hand, it can effectively utilize the physicochemical properties of clean fuels to reduce nitrogen oxides (NOx), particulate matter (PM) and greenhouse gas emissions. Currently, common low-carbon fuels for ships mainly include liquefied natural gas (LNG), methanol, biodiesel, ammonia and hydrogen. However, the idea of replacing gasoline and diesel with carbon-containing fuels such as natural gas, alcohols and liquefied petroleum gas to improve engine emissions can only alleviate environmental pollution, not cure it.

[0004] Hydrogen is a well-known "clean" energy carrier, and its greatest advantage is that it does not contain carbon and does not produce carbon-containing pollutant emissions. In addition, hydrogen also has the characteristics of cleanliness, continuous regeneration, and good combustion performance for internal combustion engines, and is expected to become an excellent fuel for replacing traditional fossil fuels as an internal combustion engine. Currently, how to ensure / and even improve the performance of the internal combustion engine while achieving stable operation of the hydrogen internal combustion engine is a difficult problem that needs to be solved at present. SUMMARY

[0005] The purpose of the present application is to provide a combustion assembly that can achieve stable operation of an internal combustion engine while ensuring the performance of the internal combustion engine.

[0006] To achieve the aforementioned combustion assembly, it comprises:

[0007] a combustion chamber;

[0008] an intake passage in communication with the combustion chamber and provided with an intake valve between the combustion chamber and the intake passage;

[0009] an exhaust passage in communication with the combustion chamber and provided with an exhaust valve between the combustion chamber and the exhaust passage;

[0010] a first gas injection unit having a first injection port extending into the intake passage;

[0011] a second gas injection unit having a second nozzle extending into the combustion chamber; and

[0012] a pilot fuel injection unit having a fuel nozzle extending into the combustion chamber.

[0013] In one or more embodiments, the combustion assembly includes a cylinder head, a cylinder liner, and a piston, which collectively define the combustion chamber.

[0014] In one or more embodiments, the second nozzle and the fuel nozzle are both offset from a geometric center of the cylinder head.

[0015] In another aspect, some embodiments of the present application also provide a hydrogen fuel supply system for an internal combustion engine, which includes a combustion assembly as described above, the first gas injection unit further includes a first hydrogen storage container, a first connecting pipeline, and a first injector having the first nozzle, the first connecting pipeline connecting the first hydrogen storage container and the first injector; the second gas injection unit further includes a second hydrogen storage container, a second connecting pipeline, and a second injector having the second nozzle, the second connecting pipeline connecting the second hydrogen storage container and the second injector; the pilot fuel injection unit further includes a fuel storage container, a third connecting pipeline, and a fuel injector having the fuel nozzle, the third connecting pipeline connecting the fuel storage container and the fuel injector, and the supply system further includes:

[0016] a control unit;

[0017] a pump body assembly arranged in the pilot fuel injection unit and being opened or closed according to an instruction of the control unit;

[0018] wherein the first injector, the second injector, and the fuel injector are opened or closed according to an instruction of the control unit.

[0019] In one or more embodiments, the first connecting pipeline further includes a first pressure sensor and a first pressure regulating valve, and the control unit adjusts the first pressure regulating valve according to a pressure signal detected by the first pressure sensor to regulate a hydrogen pressure injected by the first injector;

[0020] the second connecting pipeline further includes a second pressure sensor and a second pressure regulating valve, and the control unit adjusts the second pressure regulating valve according to a pressure signal detected by the second pressure sensor to regulate a hydrogen pressure injected by the second injector;

[0021] The third connecting pipeline is further provided with a third pressure sensor and a third pressure regulating valve, and the control unit adjusts the third pressure regulating valve according to the pressure signal detected by the third pressure sensor to adjust the fuel pressure of the fuel injector.

[0022] In one or more embodiments, the pump body assembly comprises a low-pressure pump arranged in the fuel storage container and a high-pressure pump arranged in the third connecting pipeline, the low-pressure pump being used to drive fuel to the high-pressure pump, and the high-pressure pump being used to drive fuel to the fuel injector.

[0023] In one or more embodiments, the first hydrogen storage container is a low-pressure hydrogen cylinder, and the second hydrogen storage container is a high-pressure hydrogen cylinder.

[0024] In one or more embodiments, the intake passage is further provided with an intake pressure sensor, and the cylinder head of the combustion assembly is provided with a knock sensor.

[0025] In another aspect, the application also provides a hydrogen fuel supply method for an internal combustion engine, which adjusts the hydrogen fuel supply of the internal combustion engine by using the hydrogen fuel supply system for an internal combustion engine as described above, and comprises the following steps:

[0026] According to the working load of the internal combustion engine, the working state of the internal combustion engine is divided into a first working condition, a second working condition, a third working condition, a fourth working condition, a fifth working condition and a sixth working condition, and the working load of the internal combustion engine gradually increases from the first working condition to the fifth working condition.

[0027] When the internal combustion engine is in the first working condition, the control unit instructs the fuel injector to open, while instructing the first injector and the second injector to close;

[0028] When the internal combustion engine is in the second working condition, the control unit instructs the fuel injector and the first injector to open, and instructs the second injector to close;

[0029] When the internal combustion engine is in the third working condition, the control unit instructs the fuel injector, the first injector and the second injector to open at the same time, and makes the injection time of the fuel injector later than the injection time of the second injector;

[0030] When the internal combustion engine is in the fourth working condition, the control unit instructs the first injector to close, instructs the fuel injector and the second injector to open, and makes the injection time of the fuel injector later than the injection time of the second injector;

[0031] When the internal combustion engine is in the fifth working condition, the control unit instructs the first injector to be closed, instructs the fuel injector and the second injector to be opened, and makes the injection time of the fuel injector earlier than the injection time of the second injector;

[0032] When the internal combustion engine is in the sixth working condition, the control unit gradually increases the injection amount of the fuel injector, and gradually reduces the injection amount of the first injector and / or the second injector until the first injector and the second injector are both closed and only the fuel injector is opened.

[0033] In one or more embodiments, in the first working condition, the load of the internal combustion engine is less than 20%; in the second working condition, the load of the internal combustion engine is 20% to 40%; in the third working condition, the load of the internal combustion engine is 40% to 60%; in the fourth working condition, the load of the internal combustion engine is 60% to 85%; in the fifth working condition, the load of the internal combustion engine is 85% to 100%;

[0034] Wherein, an intake pressure sensor is further arranged in the intake passage, and a knock sensor is arranged on the cylinder head of the combustion assembly, and the working condition when the load of the internal combustion engine is between 20% and 100%, the value detected by the knock sensor is greater than a knock threshold value, and the value detected by the intake pressure sensor is greater than a pressure threshold value is defined as the sixth working condition;

[0035] When the load of the internal combustion engine is between 20% and 100%, and the value detected by the knock sensor is less than the knock threshold value, the original hydrogen fuel supply strategy is continued.

[0036] In another aspect, according to some embodiments of the present application, a hydrogen fuel supply method for an internal combustion engine is also provided, which comprises the following steps:

[0037] According to the working load of the internal combustion engine, the working state of the internal combustion engine is divided into a first working condition, a second working condition, a third working condition, a fourth working condition, a fifth working condition and a sixth working condition, and the working load of the internal combustion engine gradually increases from the first working condition to the fifth working condition;

[0038] When the internal combustion engine is in the first working condition, only fuel is injected towards the combustion chamber, and no hydrogen is introduced;

[0039] When the internal combustion engine is in the second working condition, fuel is injected towards the combustion chamber, and only hydrogen is injected into the intake passage;

[0040] When the internal combustion engine is in the third working condition, fuel is injected towards the combustion chamber, hydrogen is injected into the intake port, and hydrogen is directly injected into the combustion chamber, and the injection time of the fuel is later than that of the hydrogen;

[0041] When the internal combustion engine is in the fourth working condition, fuel is injected towards the combustion chamber, hydrogen is directly injected into the combustion chamber, and the injection time of the fuel is later than that of the hydrogen;

[0042] When the internal combustion engine is in the fifth working condition, fuel is injected towards the combustion chamber, hydrogen is directly injected into the combustion chamber, and the injection time of the fuel is earlier than that of the hydrogen;

[0043] When the internal combustion engine is in the sixth working condition, the injection amount of fuel injected towards the combustion chamber is gradually increased, and the injection amount of hydrogen injected into the combustion chamber and / or the injection amount of hydrogen injected into the intake port is gradually reduced, until only fuel is injected towards the combustion chamber, and no hydrogen is injected.

[0044] In one or more embodiments, in the first working condition, the load of the internal combustion engine is less than 20%; in the second working condition, the load of the internal combustion engine is 20% to 40%; in the third working condition, the load of the internal combustion engine is 40% to 60%; in the fourth working condition, the load of the internal combustion engine is 60% to 85%; in the fifth working condition, the load of the internal combustion engine is 85% to 100%;

[0045] Wherein, the working condition when the load of the internal combustion engine is between 20% and 100%, the detected knock value is greater than the knock threshold value, and the detected intake port pressure value is greater than the pressure threshold value is defined as the sixth working condition;

[0046] When the load of the internal combustion engine is between 20% and 100%, the knock value is less than the knock threshold value, and the intake port pressure value is less than the pressure threshold value, the original hydrogen fuel supply strategy is continued.

[0047] The beneficial effects of the present application are:

[0048] The combustion assembly has the ability to emit rated power in a gaseous fuel combustion mode, and various combustion modes can be realized based on the organization of the combustion assembly. At the same time, through the hydrogen fuel supply method and system, the pilot fuel compression ignition mode can be used at 20% load and below to ensure stable operation of the engine; from 20% to 100% load, hydrogen combustion mode is realized through the combination of various hydrogen fuel supply methods, and by adjusting the fuel supply injection parameters, pilot fuel pilot intake port premixed combustion mode, pilot fuel pilot intake port and direct injection hydrogen stratified premixed combustion mode, pilot fuel pilot direct injection hydrogen stratified premixed combustion mode and pilot fuel pilot direct injection hydrogen diffusion combustion mode are formed respectively to avoid abnormal combustion and ensure stable operation of the hydrogen internal combustion engine. At the same time, the change of the distribution of hydrogen in the combustion chamber reduces the generation of NO X , ensures the performance of the hydrogen internal combustion engine, and the hydrogen replacement rate can reach greater than or equal to 80% to meet the carbon emission reduction target.

[0049] The above description is only a summary of the technical solutions of the present application. In order to enable the technical means of the present application to be more clearly understood, and to be implemented according to the content of the specification, and in order to enable the above and other purposes, features and advantages of the present application to be more apparent and easy to understand, the following specific embodiments of the present application are described. BRIEF DESCRIPTION OF DRAWINGS

[0050] By reading the detailed description of the preferred embodiments below, various other advantages and benefits will become apparent to those of ordinary skill in the art. The drawings are only for the purpose of illustrating the preferred embodiments and are not considered limiting the present application. Moreover, in all the drawings, the same reference numerals represent the same parts. In the drawings:

[0051] Figure 1 A front view of a combustion assembly according to some embodiments of the present application is shown;

[0052] Figure 2 A top view of a combustion assembly according to some embodiments of the present application is shown;

[0053] Figure 3 A schematic diagram of a hydrogen fuel supply system according to some embodiments of the present application is shown;

[0054] Figure 4 A flowchart of a hydrogen fuel supply method for an internal combustion engine according to some embodiments of the present application is shown;

[0055] Figures 5 to 8 A supply process diagram of a hydrogen fuel supply method for an internal combustion engine according to some embodiments of the present application is shown. DETAILED DESCRIPTION

[0056] The technical solutions of the present application will be described in detail below with reference to the drawings. The following embodiments are only used to more clearly illustrate the technical solutions of the present application, and therefore only serve as examples, but cannot limit the protection scope of the present application.

[0057] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present application belongs; the terms used herein are only for the purpose of describing specific embodiments of the present application, and are not intended to limit the present application; the terms "include" and "have" and any variations thereof in the specification and claims of the present application and the above description of drawings are intended to cover non-exclusive inclusion.

[0058] In the existing hydrogen internal combustion engine, the combustion organization methods mainly include (1) spark ignition pilot and (2) diesel compression ignition pilot.

[0059] For (1) spark ignition pilot, there are two ways of introducing hydrogen fuel into the cylinder: intake port premixing and high-pressure in-cylinder direct injection. Intake port premixing is that when the engine is in the intake stroke state, the injection valve sprays hydrogen fuel or hydrogen fuel mixed with natural gas and other fuel into the intake port / manifold to mix with fresh air and then enters the cylinder. The engine compresses the mixture of air and fuel in the compression stroke, and at the end of the compression stroke, the fresh charge in the cylinder is ignited by spark ignition. This method has the characteristics of simple structure and low cost. High-pressure in-cylinder direct injection is that hydrogen fuel or hydrogen fuel mixed with natural gas and other fuel is injected into the engine cylinder through the fuel injection valve after the intake valve is closed, and at the end of the compression stroke, the fresh charge in the cylinder is ignited by spark ignition. This method can avoid backfire. On the basis of the above two methods, a small amount of hydrogen fuel or hydrogen fuel mixed with natural gas and other fuel can also be introduced into the pre-chamber through a one-way valve by means of the pressure difference between the intake port and the cylinder during the intake process. A small amount of fresh charge is ignited by spark ignition in the pre-chamber, and the jet flame is ejected from the pre-chamber to ignite the fresh charge formed by intake port injection organization or the fresh charge formed by in-cylinder direct injection.

[0060] For (2) diesel compression ignition pilot, there are also two ways of introducing hydrogen fuel into the cylinder: intake port premixing and high-pressure in-cylinder direct injection. Intake port premixing is that when the engine is in the intake stroke state, the injection valve sprays hydrogen fuel or hydrogen fuel mixed with natural gas and other fuel into the intake port / manifold to mix with fresh air and then enters the cylinder. The engine compresses the mixture of air and fuel in the compression stroke, and at the end of the compression stroke, the fresh charge in the cylinder is ignited by diesel direct injection compression ignition. High-pressure in-cylinder direct injection is that hydrogen fuel or hydrogen fuel mixed with natural gas and other fuel is injected into the engine cylinder through the fuel injection valve after the intake valve is closed, and at the end of the compression stroke, the fresh charge in the cylinder is ignited by diesel direct injection compression ignition.

[0061] However, the inventors found that abnormal combustion phenomena often occur for existing hydrogen internal combustion engines, resulting in unstable operation of the hydrogen internal combustion engine. In a hydrogen-fueled internal combustion engine, abnormal combustion mainly includes three types of abnormal combustion: backfire, pre-ignition, and knock. The three types of abnormal combustion are described below.

[0062] Pre-ignition refers to a phenomenon in which hydrogen-air mixture is ignited by a hot spot in the cylinder before ignition, and pre-ignition causes combustion to get out of control, increases heat loss, and overheats the engine, easily causing the temperature of the intake valve / gate to rise and overheat, thereby causing backfire in the intake pipe. Therefore, pre-ignition also easily causes backfire.

[0063] Backfire refers to an abnormal combustion phenomenon in which, during the intake process, the flame in the cylinder spreads to the intake pipe and ignites the hydrogen-air mixture in the intake pipe before the intake valve is closed, or the hydrogen-air mixture in the intake pipe is ignited by a hot spot in the cylinder or the intake valve. Backfire generally occurs with pre-ignition and usually occurs in a relatively rich mixture condition, and is more likely to occur at high speed. When backfire occurs in a hydrogen internal combustion engine, the normal operation process is disrupted, resulting in a decrease in engine power, poor economy, and in severe cases, engine stall. Therefore, it is particularly necessary to suppress the backfire phenomenon of a hydrogen internal combustion engine.

[0064] Knock refers to a phenomenon in which, when the engine is in the intake process, the fuel mixture self-ignites and burns before the compression stroke reaches the designed ignition position due to various factors other than control. At this time, the huge impact force generated by combustion is opposite to the direction of piston movement, thereby causing the engine to vibrate.

[0065] Currently, the control method for abnormal combustion of a hydrogen-fueled internal combustion engine has the following methods:

[0066] For the backfire and pre-ignition phenomena that are prone to occur in an intake port hydrogen injection internal combustion engine, the current control method is as follows:

[0067] (1) In the initial stage of the starting process, the ignition system and the hydrogen injection system are both in the closed state. Residual hydrogen gas that may exist in the intake and exhaust systems is completely discharged through the reverse drag process, and then a transition condition of only ignition without hydrogen injection is used to reduce the risk of backfire. Finally, the hydrogen injection system starts to work to achieve the starting idle process, which can to some extent reduce the occurrence of backfire.

[0068] (2) Use a multi-path hydrogen injection system. Use a multi-path hydrogen injection system to prevent the occurrence of abnormal combustion by using parallel hydrogen injection, intake pipe delayed hydrogen injection, fixed hydrogen injection end time, and delayed ignition.

[0069] (3) Avoid injecting hydrogen at the valve overlap angle at the start of intake, minimize the residence time of hydrogen in the intake pipe, and reduce the probability of mixture ignition by cooling the hot spots in the intake manifold in the early stage to reduce the probability of backfire.

[0070] For the early combustion and knock phenomena that may occur in the hydrogen internal combustion engine with intake port hydrogen injection, the commonly used control methods are as follows:

[0071] (1) By means of the secondary injection of in-cylinder direct injection hydrogen to form a lean combustion zone and a rich combustion zone in the combustion chamber, the combustion zone prone to generating NOx is avoided. At the same time, the spark-assisted ignition and diffusion combustion control method of the hydrogen internal combustion engine is adopted, and the high output power, high thermal efficiency and low NOx emission of the in-cylinder direct injection hydrogen internal combustion engine are realized through the specific control of the electronic control unit.

[0072] (2) Based on the hydrogen internal combustion engine control device with controllable mixture activity, water vapor recycling and in-cylinder direct injection of hydrogen and water are adopted, the hydrogen injection time and water injection time are controlled, the hydrogen internal combustion engine mixture composition and activity are regulated, the in-cylinder mixed gas thermodynamic state before the ignition time of the hydrogen internal combustion engine is controlled, and thus the combustion rate of the hydrogen internal combustion engine is regulated to eliminate the in-cylinder knock combustion.

[0073] However, the inventors have found in practice that for the hydrogen internal combustion engine with intake port injection, the hydrogen occupying a part of the cylinder working volume will result in a small charge coefficient and low output power, and may induce abnormal combustion phenomena such as early combustion, backfire and knock. Although the aforementioned methods can suppress the occurrence of abnormal combustion phenomena, abnormal combustion may still occur. The in-cylinder direct injection hydrogen internal combustion engine avoids the hydrogen occupying the cylinder working volume, improves the charge coefficient, and can to some extent suppress the occurrence of abnormal combustion. However, how to reasonably design the overall system of the in-cylinder direct injection hydrogen internal combustion engine is a difficult problem currently faced. In addition, the high performance and low emission of the in-cylinder direct injection hydrogen internal combustion engine are related to the formation and combustion mode of the hydrogen and air mixture. The unreasonable hydrogen injection strategy and combustion control method of the in-cylinder direct injection hydrogen internal combustion engine are not conducive to improving the engine performance and improving the engine emission level.

[0074] In view of the above problems, according to some embodiments of the present application, a combustion assembly is provided, which can realize stable operation of the hydrogen internal combustion engine under the premise of ensuring the performance of the hydrogen internal combustion engine. As shown in Figure 1 a front view of the combustion assembly according to some embodiments of the present application is shown, Figure 2 a top view of the combustion assembly according to some embodiments of the present application is shown.

[0075] According to some embodiments of the present application, the combustion assembly 100 comprises an intake port 1, an exhaust port 2, a combustion chamber 3, a first gas injection unit 4, a second gas injection unit 5 and an ignition fuel injection unit 6.

[0076] The intake passage 1 is in communication with the combustion chamber 3, and the intake valve 7 is arranged between the intake passage 1 and the combustion chamber 3. The exhaust passage 2 is in communication with the combustion chamber 3, and the exhaust valve 8 is arranged between the exhaust passage 2 and the combustion chamber 3. The opening and closing of the intake valve 7 defines the intake action of the combustion assembly, and the opening and closing of the exhaust valve 8 defines the exhaust action of the combustion assembly.

[0077] The first gas injection unit 4 has a first injection port 40, which is the position where the gas fuel, such as hydrogen, is injected from the first gas injection unit 4. In the embodiment shown in the figure, the first injection port 40 extends into the intake passage 1 in the assembled state, so that the gas fuel injected from the first gas injection unit 4 first enters the intake passage 1. The second gas injection unit 5 has a second injection port 50, which is also the position where the gas fuel, such as hydrogen, is injected from the second gas injection unit 5. The second injection port 50 extends into the combustion chamber 3 in the assembled state, so that the gas fuel injected from the second injection port 50 directly enters the combustion chamber 3. In the description of the embodiments of the present application, the technical terms "first XX" and "second XX", such as "first injection port" and "second injection port", are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features.

[0078] The pilot fuel injection unit 6 has a fuel injection port 50, which is the position where the fuel is injected from the pilot fuel injection unit 6. In the assembled state, the fuel injection port 50 extends into the combustion chamber 3, so that the fuel injected from the fuel injection port 50 directly enters the combustion chamber 3.

[0079] The combustion assembly with the foregoing configuration can realize the introduction of hydrogen through the intake passage 1 alone, the direct injection of hydrogen into the combustion chamber 3 alone, and the simultaneous introduction of hydrogen through the intake passage 1 and the direct injection of hydrogen into the combustion chamber 3, so that the internal combustion engine with it can have various combustion mode organization forms to cope with different working conditions, providing a basis for stable operation of the hydrogen internal combustion engine.

[0080] Further, in a specific embodiment, the combustion assembly 100 includes a cylinder head 31, a cylinder sleeve 32, and a piston 33, and the piston 33 has a recess 330 above it, and the cylinder head 31, the cylinder sleeve 32, and the recess 330 above the piston 33 collectively define the combustion chamber 3.

[0081] Further, in a specific embodiment, in combination with Figure 1 and Figure 2As shown, the second injection port 40 and the fuel injection port 50 are both arranged offset from the geometric center of the cylinder head 31. By the offset arrangement, installation positions can be reserved for the second injection port 40 and the fuel injection port 50, and air utilization of hydrogen from the second injection port 40 and pilot fuel from the fuel injection port 50 can be improved, thereby ensuring power output of the hydrogen internal combustion engine.

[0082] In another aspect, according to some embodiments of the present application, a hydrogen fuel supply system for an internal combustion engine is also provided, which includes the combustion assembly 100 as recited in one or more of the preceding embodiments, such as Figure 3 A schematic diagram of the hydrogen fuel supply system according to some embodiments of the present application is shown.

[0083] As Figure 3 As shown, the supply system further includes a control unit 101, which in some embodiments can be a microprocessor or computer programmed together.

[0084] The first gas injection unit 4 further comprises a first injector 41, a first hydrogen storage container 42 and a first connecting pipe 43. The first injector 41 has a first injection port 40. The first hydrogen storage container 42 is a container for storing hydrogen, such as a hydrogen tank. The first connecting pipe 43 is a pipe, such as a rigid pipe or a flexible hose, which is configured to connect the first hydrogen storage container 42 and the first injector 41. The second gas injection unit 5 further comprises a second injector 51, a second hydrogen storage container 52 and a second connecting pipe 53. The second injector 51 has a second injection port 50. The second hydrogen storage container 52 is a container for storing hydrogen, such as a hydrogen tank. The second connecting pipe 53 is a pipe, such as a rigid pipe or a flexible hose, which is configured to connect the second hydrogen storage container 52 and the second injector 51. The pilot fuel injection unit 6 further comprises a fuel injector 61, a fuel storage container 62 and a third connecting pipe 63. The fuel injector 61 has a fuel injection port 50. The fuel storage container 62 is a container for storing fuel, such as a fuel tank. The third connecting pipe 63 is a pipe, such as a rigid pipe or a flexible hose, which is configured to connect the fuel storage container 62 and the fuel injector 61. It is understood that the first injector 41, the second injector 51 and the fuel injector 61 are devices which are configured to allow a fluid under pressure to be injected through a nozzle. The first injector 41, the second injector 51 and the fuel injector 61 have an open state and a closed state. In the open state, the first injector 41, the second injector 51 and the fuel injector 61 allow the fluid to be injected through the nozzle. In the closed state, the first injector 41, the second injector 51 and the fuel injector 61 prevent the fluid from being injected through the nozzle. In one or more embodiments, the first injector 41, the second injector 51 and the fuel injector 61 are configured to switch between the open state and the closed state according to a command from the control unit 101. In the pilot fuel injection unit 6, a pump assembly is configured to drive the fuel to flow from the fuel storage container 62 to the fuel injector 61 in the open state. The pump assembly is configured to be switched between the open state and the closed state according to a command from the control unit 101.

[0085] In some specific embodiments, the pump body assembly comprises a low-pressure pump 64 arranged in the fuel storage container 62 and a high-pressure pump 65 arranged in the third connecting pipeline 63, the low-pressure pump 64 is used to drive the fuel supply to the high-pressure pump 65, and the high-pressure pump 65 is used to drive the fuel supply to the fuel injector 61. The foregoing supply action is performed according to the instruction of the control unit 101, so as to form fuel with a certain pressure in the fuel injector 61, and when the control unit 101 instructs the fuel injector 61 to open the port, the pilot fuel with a certain pressure can be injected from the fuel injection port 50. Among them, the low-pressure pump 64 pumps the pilot fuel in the fuel storage container 62 to the fuel pump of the high-pressure pump 65, the pilot fuel pumped by the low-pressure pump 64 has a supply pressure of 0.3-1.5 MPa, and the high-pressure pump 65 pressurizes the supply pressure of the pilot fuel pumped by the low-pressure pump 64 to a fuel pump of 60 MPa or more. By arranging the low-pressure pump 64 and the high-pressure pump 65, the pilot fuel can be supplied from the fuel storage container 62 to the fuel injection port 60, while ensuring that the pilot fuel injection pressure is greater than 60 MPa, and under the control of the control unit, the pilot fuel is directly injected into the combustion chamber to organize combustion.

[0086] In some specific embodiments, the first hydrogen storage container 42 is a low-pressure hydrogen cylinder, and the second hydrogen storage container 52 is a high-pressure hydrogen cylinder, wherein the low-pressure hydrogen cylinder refers to a hydrogen cylinder with an injection pressure of 0.8-1.5 MPa, and the high-pressure hydrogen cylinder refers to a hydrogen cylinder with an injection pressure of 35-75 MPa. By configuring the low-pressure hydrogen cylinder and the high-pressure hydrogen cylinder, hydrogen can be supplied to the first injector 41 and the second injector 51 respectively to inject hydrogen into the intake port 1 and the combustion chamber 3 respectively. With the opening of the intake valve 7, the hydrogen in the intake port 1 enters the cylinder to form uniform hydrogen-air mixture, and the hydrogen from the second injector 51 is injected into the combustion chamber 3 to form stratified premixed hydrogen-air mixture.

[0087] In another aspect, according to some embodiments of the present application, a hydrogen fuel supply method for an internal combustion engine is also provided, which adjusts the hydrogen fuel supply of the internal combustion engine by using the hydrogen fuel supply system described in one or more of the foregoing embodiments, such as Figure 4 A flowchart of a hydrogen fuel supply method for an internal combustion engine according to some embodiments of the present application is shown, which comprises the following steps:

[0088] Step S1: According to the working load of the internal combustion engine, the working state of the internal combustion engine is divided into first, second, third, fourth, fifth and sixth working conditions, and the working load of the internal combustion engine gradually increases from the first to the fifth working conditions.

[0089] Step S2: When the internal combustion engine is in the first working condition, the control unit 101 instructs the fuel injector 61 to open, and at the same time instructs the first injector 41 and the second injector 51 to close. That is, as Figure 5As shown in the state, only fuel injected by the fuel injector 61 is present in the combustion chamber 3. At this time, the engine is in a starting state, and only fuel is injected by the fuel injector 61 to organize a pilot fuel combustion mode of the internal combustion engine to ensure normal starting.

[0090] Step S3: When the internal combustion engine is in the second operating condition, the control unit 101 instructs the fuel injector 61 and the first injector 41 to be turned on and instructs the second injector 51 to be turned off. That is, as shown in the state, Figure 6 As shown in the state, the combustion chamber 3 is filled with hydrogen gas injected by the first injector 41 and hydrogen gas entering the combustion chamber 3 from the intake port, which is represented by black dots in the figure. At this time, the internal combustion engine is in a low load operating condition, and hydrogen gas is injected by the first injector 41 to cause hydrogen gas to enter the combustion chamber 3 from the intake port to organize a pilot fuel ignition premixed hydrogen mixture combustion mode, thereby avoiding backfiring of the internal combustion engine and improving thermal efficiency of the internal combustion engine.

[0091] Step S4: When the internal combustion engine is in the third operating condition, the control unit 101 instructs the fuel injector 61, the first injector 41, and the second injector 51 to be turned on at the same time, and the injection timing of the fuel injector 61 is later than the injection timing of the second injector 51. That is, as shown in the state, Figure 7 As shown in the state, the combustion chamber 3 is filled with hydrogen gas injected by the first injector 41 and hydrogen gas entering the combustion chamber 3 from the intake port, which is represented by black dots in the figure, and also contains hydrogen gas directly injected into the combustion chamber by the second injector 51, which is represented by white circles a in the figure. At this time, the internal combustion engine is in a medium load operating condition, and the fuel injector 61 is used to inject pilot fuel to ignite stratified hydrogen-air mixture formed by hydrogen gas directly injected by the second injector 51 and air from the intake port, thereby avoiding knocking and reducing generation of NOX.

[0092] Step S5: When the internal combustion engine is in the fourth operating condition, the control unit 101 instructs the first injector 41 to be turned off, instructs the fuel injector 61 and the second injector 51 to be turned on, and the injection timing of the fuel injector 61 is later than the injection timing of the second injector 51. That is, as shown in the state, Figure 8 As shown in the state, the combustion chamber 3 only contains hydrogen gas directly injected by the second injector 51. At this time, the internal combustion engine is in a medium-high load operating condition, and the injection timing of the fuel injector 61 is later than the injection timing of the in-cylinder direct injection hydrogen gas, thereby forming hydrogen stratified lean combustion, improving thermal efficiency of the internal combustion engine, avoiding knocking, and reducing generation of NOX. X

[0093] Step S6: When the internal combustion engine is in the fifth operating condition, the control unit 101 instructs the first injector 41 to be turned off, instructs the fuel injector 61 and the second injector 51 to be turned on, and the injection timing of the fuel injector 61 is earlier than the injection timing of the second injector 51. Also as shown in the state, Figure 8 ​The state shown, the combustion chamber 3 only contains hydrogen gas directly injected from the second injector 51. At this time, the internal combustion engine is in a high load working condition, the injection time of the pilot fuel is earlier than the injection time of the directly injected hydrogen gas in the cylinder, forming the diffusion combustion of the pilot fuel with the pilot hydrogen gas, ensuring that the hydrogen replacement rate reaches 95% and above.

[0094] Step S7: When the internal combustion engine is in the sixth working condition, the control unit 101 gradually increases the injection amount of the fuel injector 61, and gradually reduces the injection amount of the first injector 41 and / or the second injector 51, until the first injector 41 and the second injector 51 are both closed, and only the fuel injector 61 is opened. The final state returns to the state shown in Figure 5

[0095] Further, in some specific embodiments, as shown in Figure 3 The intake port 1 is also provided with an intake pressure sensor 102, and the cylinder head of the combustion assembly is provided with a knock sensor 103.

[0096] In the hydrogen fuel supply method of the internal combustion engine, specifically, in the first working condition, the load of the internal combustion engine is less than 20%; in the second working condition, the load of the internal combustion engine is 20% to 40%; in the third working condition, the load of the internal combustion engine is 40% to 60%; in the fourth working condition, the load of the internal combustion engine is 60% to 85%; in the fifth working condition, the load of the internal combustion engine is 85% to 100%.

[0097] The sixth working condition is when the load of the internal combustion engine is between 20% and 100%, and the value detected by the knock sensor 103 is greater than the knock threshold value, and the value detected by the intake pressure sensor 102 is greater than the pressure threshold value. In this sixth working condition, the signals detected by the knock sensor 103 and the intake pressure sensor 102 can determine that there is abnormal combustion (backfire, pre-ignition, knock) in the internal combustion engine. At the same time, by judging that the value detected by the knock sensor 103 is greater than the knock threshold value, and the value detected by the intake pressure sensor 102 is greater than the pressure threshold value, it can be determined that the abnormal combustion phenomenon cannot be suppressed by adjusting the injection time of the fuel injector 61, the injection time of the first injector 41 and the second injector 51. At this time, only by gradually reducing the amount of hydrogen gas injected by the first injector 41 and the second injector 51, and gradually increasing the fuel injection amount of the fuel injector 61 to maintain the engine output power unchanged, the engine can finally be operated in the pilot fuel combustion mode until the engine is unloaded and stopped. In some embodiments, the size of the pressure threshold value and the knock threshold value is selected according to different configurations of the internal combustion engine, for example, appropriate values are obtained through multiple trial and error tests.

[0098] ​When the load of the internal combustion engine is between 20% and 100%, i.e. in the second to fifth operating conditions, and the value detected by the knock sensor 103 is less than the knock threshold value, while the value detected by the intake pressure sensor 102 is less than the pressure threshold value, the original hydrogen fuel supply strategy is maintained. For example, when knock is detected in the second operating condition, but the magnitude of the knock vibration is less than the knock threshold value, the fuel supply state in the second operating condition is maintained, and the injection time of the fuel injector 61 and the injection parameters of the first injector 41 and the second injector 51 are reasonably adjusted. For example, the occurrence of knock can be suppressed by delaying the injection time of the fuel injector 61 and the second injector 51, or by delaying the injection time of the fuel injector 61 and increasing the interval between the injection of the fuel injector 61 and the second injector 51, or by delaying the injection time of the first injector 41 to suppress the occurrence of pre-ignition, or by adjusting the premixed combustion ratio by injecting the fuel in the fuel injector 61 twice, or by controlling the injection time of the second injector 51 to be later than the injection time of the fuel injector 61, or by using the above-mentioned means in combination with optimization in different operating conditions to eliminate abnormal combustion states.

[0099] In some specific embodiments, the first connecting pipeline 43 is further provided with a first pressure sensor 431 and a first pressure regulating valve 432, and the control unit 101 adjusts the first pressure regulating valve 431 according to the pressure signal detected by the first pressure sensor 431 to adjust the hydrogen pressure injected by the first injector 41. The second connecting pipeline 53 is further provided with a second pressure sensor 531 and a second pressure regulating valve 532, and the control unit 101 adjusts the second pressure regulating valve 532 according to the pressure signal detected by the second pressure sensor 531 to adjust the hydrogen pressure injected by the second injector 51. The third connecting pipeline 63 is further provided with a third pressure sensor 631 and a third pressure regulating valve 632, and the control unit 101 adjusts the third pressure regulating valve 632 according to the pressure signal detected by the third pressure sensor 631 to adjust the fuel pressure injected by the fuel injector 61. The control system 101 can determine whether the supply of low-pressure hydrogen, high-pressure hydrogen, and pilot fuel is normal according to the first pressure sensor 431, the second pressure sensor 531, and the third pressure sensor 631, and adjust the supply pressure accordingly to achieve accurate adjustment of the supply. In a specific embodiment, the third pressure regulating valve 632 is a pressure relief valve. In some specific embodiments, the first pressure sensor 431, the second pressure sensor 531, and the third pressure sensor 631 are connected to the control unit 101 by wired or wireless electrical connection, such as electrical signal connection, and the first to third pressure regulating valves are also connected to the control unit 101 by wired or wireless electrical connection, such as electrical signal connection.

[0100] In some embodiments, the control unit 101 controls the first injector 41 to inject hydrogen into the intake passage 1 at a timing that avoids the overlap region of the intake valve 7 and the exhaust valve 8, thereby ensuring the intake efficiency. Specifically, the intake valve 7 is connected to an intake cam 71, and the exhaust valve 8 is connected to an exhaust cam 81. A camshaft sensor 104 is provided on the intake cam 71. The control unit 101 detects the phase of the intake cam 71 through the camshaft sensor 104 to determine whether the intake valve 7 and the exhaust valve 8 are in the overlap region.

[0101] In some embodiments, the exhaust passage 2 is further provided with an exhaust pressure sensor 21 and an exhaust temperature sensor 22, which are connected to the control unit 101 through wired or wireless connection, so that the control unit 101 can determine the temperature and pressure in the exhaust passage 2 to identify the operating state of the combustion assembly.

[0102] In another aspect, the application also provides a hydrogen fuel supply method for an internal combustion engine, which can be implemented by using the hydrogen fuel supply system as described above. The method comprises the following steps:

[0103] First, according to the working load of the internal combustion engine, the working state of the internal combustion engine is divided into first, second, third, fourth, fifth and sixth working conditions. The working load of the internal combustion engine gradually increases from the first to the fifth working conditions.

[0104] Subsequently, when the internal combustion engine is in the first working condition, only fuel is injected into the combustion chamber, and no hydrogen is introduced.

[0105] Subsequently, when the internal combustion engine is in the second working condition, fuel is injected into the combustion chamber, and only hydrogen is injected into the intake passage.

[0106] Subsequently, when the internal combustion engine is in the third working condition, fuel is injected into the combustion chamber, and hydrogen is injected into the intake passage and directly into the combustion chamber.

[0107] Subsequently, when the internal combustion engine is in the fourth working condition, fuel is injected into the combustion chamber, and only hydrogen is directly injected into the combustion chamber, and the injection timing of the fuel is later than that of the hydrogen.

[0108] Subsequently, when the internal combustion engine is in the fifth working condition, fuel is injected into the combustion chamber, and only hydrogen is directly injected into the combustion chamber, and the injection timing of the fuel is earlier than that of the hydrogen.

[0109] Finally, when the internal combustion engine is in the sixth working condition, the injection amount of fuel injected toward the combustion chamber is gradually increased, and the injection amount of hydrogen injected toward the combustion chamber and / or the injection amount of hydrogen injected toward the intake port is gradually decreased until only fuel is injected toward the combustion chamber and no hydrogen is introduced.

[0110] On the basis of the foregoing embodiment, the hydrogen fuel supply method of the internal combustion engine further includes the following details. Specifically, in the first working condition, the load of the internal combustion engine is less than 20%; in the second working condition, the load of the internal combustion engine is 20% to 40%; in the third working condition, the load of the internal combustion engine is 40% to 60%; in the fourth working condition, the load of the internal combustion engine is 60% to 85%; and in the fifth working condition, the load of the internal combustion engine is 85% to 100%. The working condition in which the load of the internal combustion engine is between 20% and 100% and the simultaneously detected knock value is greater than the knock threshold value is defined as the sixth working condition. When the load of the internal combustion engine is between 20% and 100% and the knock value is less than the knock threshold value, the original hydrogen fuel supply strategy is continued.

[0111] The hydrogen fuel supply method of the internal combustion engine is further described in detail below through a specific embodiment thereof:

[0112] First, after the engine is warmed up, the engine is started.

[0113] Finally, the control unit 101 of the engine controls the start of the pilot fuel low-pressure pump 64 to supply pilot fuel from the pilot fuel tank to the pilot fuel high-pressure pump 65, and the high-pressure pump 65 supplies the pilot fuel to the third connection pipeline 63 connected to the fuel injector 61. The control unit 101 of the engine analyzes the signal of the third pressure sensor 631, controls the opening and closing of the pilot fuel supply third pressure regulating valve 632, and adjusts the pilot fuel supply pressure to the target value. The first hydrogen storage container 42, the first pressure regulating valve 431, the second hydrogen storage container 52, and the second pressure regulating valve 532 are opened. The control unit 101 of the engine judges whether the low-pressure and high-pressure hydrogen supply is normal by inputting signals from the first pressure sensor 431 and the second pressure sensor 531. At this time, the engine is in the first working condition, and if the low-pressure and high-pressure hydrogen supply is normal, the engine can be started, otherwise the engine cannot be started.

[0114] Subsequently, the engine is started, and if the start is unsuccessful, the control unit 101 of the engine adjusts the fuel injection parameters of the fuel injector 61 and starts again. After the start is successful, the engine enters the second working condition.

[0115] When the engine load is 20%, the engine control unit 101 determines that the speed fluctuation is less than or equal to 10 rpm, the engine control unit 101 drives the first injector 41 to open, adjusts the first injector 41 to spray hydrogen into the intake port 1 at a time when the intake valve 7 and the exhaust valve 8 are not overlapped, and controls the fuel injector 61 to gradually reduce the injection pulse width, the engine control unit 101 controls the first injector 41 to gradually increase the injection pulse width to maintain the power unchanged, and the switching is successful, and the next stage can be entered. If the engine speed fluctuation is greater than 10 rpm, the fuel injection strategy of the fuel injector 61 is adjusted until the speed fluctuation is less than or equal to 10 rpm.

[0116] Subsequently, the engine control unit 101 controls the fuel injector 61 to gradually reduce the injection pulse width to a fixed value, the engine control unit 101 controls the first injector 41 to gradually increase the injection pulse width to maintain the power unchanged, and the engine operates in the pilot fuel and premixed hydrogen combustion mode. The engine control unit 101 analyzes the vibration signal transmitted from the knock sensor 103 and the pressure information transmitted from the intake pressure sensor 102, determines whether backfire, pre-ignition and knock occur, and if the intensity is controllable, the third working condition can be entered after adjusting the pilot fuel injection strategy; if the intensity is uncontrollable, the sixth working condition is entered.

[0117] Subsequently, when the engine load is 40%, the engine control unit 101 controls the second injector 51 to open, maintains the proportion of hydrogen sprayed by the second injector 51 and the first injector 41 at 20%:80% under the condition that the total hydrogen injection amount is unchanged, and the injection strategy of the fuel injector 61 remains unchanged, and the engine operates in the pilot fuel and stratified premixed hydrogen combustion mode. The engine control unit 101 analyzes the vibration signal transmitted from the knock sensor 103 and the pressure information transmitted from the intake pressure sensor 102, determines whether backfire, pre-ignition and knock occur, and if the intensity is controllable, the fourth working condition can be entered after adjusting the pilot fuel injection strategy; if the intensity is uncontrollable, the sixth working condition is entered.

[0118] When the engine load is 60%, the engine control unit 101 controls the first injector 41 to close, controls the second injector 51 to open, increases the second injector 51 injection duration, controls the injection pulse width of the fuel injector 61 to be unchanged, and the injection time of the fuel injector 61 is later than the injection time of the second injector 51, and the engine operates in the pilot fuel and stratified hydrogen lean burn mode. The engine control unit 101 analyzes the vibration signal transmitted from the knock sensor 103, determines whether pre-ignition and knock occur, and if the intensity is controllable, the fifth working condition can be entered after adjusting the pilot fuel injection strategy; if the intensity is uncontrollable, the sixth working condition is entered.

[0119] When the engine load is 85%, the control unit 101 of the engine controls the second injector 51 to open, and controls the injection timing of the fuel injector 61 to be earlier than the injection timing of the second injector 51, so as to operate in the pilot fuel-pilot hydrogen diffusion combustion mode. The control unit 101 of the engine analyzes the knock signal transmitted from the knock sensor 103, judges whether the pre-ignition and knock occur, and if the intensity is controllable, adjusts the pilot fuel injection strategy, and after the engine load is 100% and operates for a period of time, the engine is unloaded and stopped, and if the intensity is uncontrollable, it is judged to enter the sixth working condition.

[0120] When it is judged that abnormal combustion (backfire, pre-ignition, knock) is uncontrollable, the supply strategy corresponds to the sixth working condition, at this time the control unit 101 of the engine controls the first injector 41 to gradually reduce the injection pulse width, controls the second injector 51 to gradually reduce the injection pulse width, controls the fuel injector 61 to gradually increase the injection pulse width, maintains the engine output power unchanged, and finally converts to the pilot fuel combustion mode, and the engine is unloaded and stopped.

[0121] The combustion assembly described in one or more of the foregoing embodiments has the ability to output rated power in hydrogen combustion mode, and based on the combustion assembly, multiple combustion modes can be organized. At the same time, through the hydrogen fuel supply method and system described in one or more of the foregoing embodiments, the pilot fuel compression ignition mode can be used at 20% load and below to ensure stable operation of the engine; from 20% to 100% load, hydrogen combustion mode is realized through the combination of multiple hydrogen fuel supply methods, and by adjusting the fuel supply injection parameters, the pilot fuel pilot intake port premixed combustion mode, the pilot fuel pilot intake port and direct injection hydrogen stratified premixed combustion mode, the pilot fuel pilot direct injection hydrogen stratified premixed combustion mode, and the pilot fuel pilot direct injection hydrogen diffusion combustion mode are formed respectively, to avoid abnormal combustion and ensure stable operation of the hydrogen internal combustion engine, while the change in the distribution of hydrogen in the combustion chamber reduces the generation of NO X , and ensures the performance of the hydrogen internal combustion engine, while the hydrogen replacement rate can reach greater than or equal to 80% to meet the carbon emission reduction target.

[0122] Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the application. The appearances of the phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are they necessarily mutually exclusive of one another. As will be apparent to those of ordinary skill in the art, embodiments described herein can be combined with other embodiments.

[0123] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than limit them. Although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those skilled in the art that the technical solutions recorded in the foregoing embodiments can be modified, or some or all of the technical features can be replaced equivalently. These modifications or replacements do not change the essence of the corresponding technical solutions, which should be covered in the scope of the present application. In particular, the technical features mentioned in each embodiment can be combined in any way as long as there is no structural conflict. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A hydrogen fuel supply method for an internal combustion engine, characterized by, Includes the following steps: Based on the workload of the internal combustion engine, the working states of the internal combustion engine are divided into a first working condition, a second working condition, a third working condition, a fourth working condition, a fifth working condition, and a sixth working condition. From the first working condition to the fifth working condition, the workload of the internal combustion engine gradually increases. When the internal combustion engine is in the first operating condition, fuel is injected only toward the combustion chamber, and hydrogen is not introduced; When the internal combustion engine is in the second operating condition, fuel is injected toward the combustion chamber, while hydrogen is injected only into the intake manifold; When the internal combustion engine is in the third operating condition, fuel is injected toward the combustion chamber, hydrogen is injected into the intake manifold, and hydrogen is injected directly into the combustion chamber, while the fuel injection time is later than the hydrogen injection time. When the internal combustion engine is in the fourth operating condition, fuel is injected toward the combustion chamber, and hydrogen is injected directly into the combustion chamber, while the fuel injection time is later than the hydrogen injection time. When the internal combustion engine is in the fifth operating condition, fuel is injected toward the combustion chamber, and hydrogen is injected directly into the combustion chamber, while the fuel injection time is earlier than the hydrogen injection time. When the internal combustion engine is in the sixth operating condition, the amount of fuel injected into the combustion chamber is gradually increased, and the amount of hydrogen injected into the combustion chamber and / or the amount of hydrogen injected into the intake manifold is gradually decreased until only fuel is injected into the combustion chamber and no hydrogen is introduced. Under the first operating condition, the load on the internal combustion engine is less than 20%; under the second operating condition, the load on the internal combustion engine is 20% to 40%. Under the third operating condition, the load on the internal combustion engine is 40% to 60%. In the fourth operating condition, the load on the internal combustion engine is 60% to 85%. Under the fifth operating condition, the load on the internal combustion engine is 85% to 100%. The sixth operating condition is defined as the condition in which the load of the internal combustion engine is between 20% and 100%, and the detected knock value is greater than the knock threshold and the detected intake manifold pressure value is greater than the pressure threshold. When the load of the internal combustion engine is between 20% and 100%, and the knock value is less than the knock threshold and the intake manifold pressure value is less than the pressure threshold, the original hydrogen fuel supply strategy will continue.

2. A hydrogen fuel supply system for an internal combustion engine, characterized by, To implement the hydrogen fuel supply method as described in claim 1, comprising: Combustion assembly, the combustion assembly comprising: Combustion chamber; An air intake duct is connected to the combustion chamber, and an intake valve is provided between the air intake duct and the combustion chamber; An exhaust duct is connected to the combustion chamber, and an exhaust valve is provided between the exhaust duct and the combustion chamber; A first gas injection unit has a first nozzle that extends into the air intake duct. A second gas injection unit has a second nozzle that extends into the combustion chamber; and An ignition fuel injection unit has a fuel nozzle that extends into the combustion chamber; The first gas injection unit further comprises a first hydrogen storage container, a first connecting pipeline and a first injector having the first injection port, the first connecting pipeline connecting the first hydrogen storage container and the first injector; the second gas injection unit further comprises a second hydrogen storage container, a second connecting pipeline and a second injector having the second injection port, the second connecting pipeline connecting the second hydrogen storage container and the second injector; the pilot fuel injection unit further comprises a fuel storage container, a third connecting pipeline and a fuel injector having the fuel injection port, the third connecting pipeline connecting the fuel storage container and the fuel injector, The supply system further comprises: a control unit; a pump body assembly arranged in the pilot fuel injection unit and opened or closed according to the instruction of the control unit; wherein the first injector, the second injector and the fuel injector are opened or closed according to the instruction of the control unit.

3. The hydrogen fuel supply system for an internal combustion engine according to claim 2, characterized by, The combustion assembly comprises a cylinder head, a cylinder liner and a piston, which jointly define the combustion chamber.

4. The hydrogen fuel supply system for an internal combustion engine according to claim 3, characterized by The second injection port and the fuel injection port are both arranged away from the geometric center of the cylinder head.

5. The hydrogen fuel supply system for internal combustion engine according to claim 2, wherein the first connecting pipeline further comprises a first pressure sensor and a first pressure regulating valve, the control unit adjusts the first pressure regulating valve according to the pressure signal detected by the first pressure sensor to adjust the hydrogen pressure injected by the first injector; the second connecting pipeline further comprises a second pressure sensor and a second pressure regulating valve, the control unit adjusts the second pressure regulating valve according to the pressure signal detected by the second pressure sensor to adjust the hydrogen pressure injected by the second injector; the third connecting pipeline further comprises a third pressure sensor and a third pressure regulating valve, the control unit adjusts the third pressure regulating valve according to the pressure signal detected by the third pressure sensor to adjust the fuel pressure injected by the fuel injector.

6. The hydrogen fuel supply system for internal combustion engine according to claim 2, wherein the pump body assembly comprises a low-pressure pump arranged in the fuel storage container and a high-pressure pump arranged in the third connecting pipeline, the low-pressure pump is used to drive the fuel supply to the high-pressure pump, and the high-pressure pump is used to drive the fuel supply to the fuel injector.

7. The hydrogen fuel supply system for an internal combustion engine according to claim 2, characterized by The first hydrogen storage container is a low-pressure hydrogen cylinder, and the second hydrogen storage container is a high-pressure hydrogen cylinder.

8. The hydrogen fuel supply system for an internal combustion engine according to claim 2, characterized by, An intake pressure sensor is arranged in the intake passage, and a knock sensor is arranged on the cylinder head of the combustion assembly.

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