Vehicle hydrogen-doped compressed natural gas supply system and method

Abstract

The invention relates to the technical field of vehicle hydrogen energy power generation, and discloses a vehicle hydrogen-doped compressed natural gas supply system and method.The vehicle hydrogen-doped compressed natural gas supply system comprises a main pipeline connected with a vehicle HCNG engine, and the other end of the main pipeline is connected with a gaseous natural gas regulation and control pipeline and a gaseous hydrogen regulation and control pipeline; the gaseous natural gas regulation and control pipeline comprises a compressed natural gas bottle and a natural gas flow regulating valve connected with the outlet end of the compressed natural gas bottle; the gaseous hydrogen regulating and controlling pipeline comprises a hydrogen cylinder and a hydrogen flow regulating valve connected with the outlet end of the hydrogen cylinder. The flow of compressed natural gas and hydrogen is controlled in real time according to requirements, the proportion of mixed gas is accurately adjusted, the requirements of different hydrogen-doped compressed natural gas (HCNG) fuel engines and the same engine for variable working conditions can be met, safe and reliable operation of the compressed natural gas supply system is ensured, and the service life of the compressed natural gas supply system is prolonged. And the emission performance and the economic efficiency of the compressed natural gas automobile are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of vehicle hydrogen power generation, and in particular to a vehicle hydrogen-blended compressed natural gas supply system and method. Background Art

[0002] At present, with the increasing attention paid to clean energy and sustainable development technology around the world, hydrogen-blended natural gas (HCNG) as a low-carbon, environmentally friendly alternative fuel is gradually being promoted and applied in the automotive industry in the trial stage. HCNG fuel vehicles mainly use compressed natural gas cylinders or special cylinders designed for HCNG to store fuel. The working pressure of these cylinders is usually set at 20MPa to ensure sufficient energy density and endurance.

[0003] However, in actual applications, HCNG gas needs to be mixed with natural gas in a fixed ratio before filling. This step usually relies on dedicated compressed natural gas pipe valves to ensure the accuracy and safety of the mixing process.

[0004] However, with the continuous advancement of modern automobile technology and diversified needs, the pre-set HCNG mixing ratio is difficult to meet the combustion needs of various automobile engines. For example, different driving modes, road conditions, and vehicle loads may have a significant impact on the fuel's combustion efficiency and emission performance, resulting in incomplete combustion, energy waste, or increased pollution emissions. If the mixing ratio is changed according to automobile technology, it usually means that the entire engine system needs to be replaced, which is not only costly, but also extremely inconvenient in actual operation. As a result, it is difficult for the existing HCNG fuel system to adjust the mixing ratio of hydrogen and natural gas in real time according to these changes to optimize the mixing ratio, improve combustion efficiency, and reduce emissions.

[0005] In addition, in order to support the operation of HCNG fuel vehicles, it is necessary to build dedicated HCNG refueling stations separately, which not only requires high infrastructure investment, but is also not economically efficient. The construction and maintenance costs of HCNG stations are much higher than traditional natural gas refueling stations, and because HCNG stations are emerging facilities, their safety standards and regulatory systems are not yet perfect, and there are certain safety hazards. This not only affects the speed of popularization of HCNG fuel vehicles, but also increases public concerns about their safety, limiting the effective promotion and application of new energy. Summary of the invention

[0006] The present invention is intended to provide a vehicle hydrogen-blended compressed natural gas supply system and method to solve the problem that the mixing ratio of the existing vehicle hydrogen-blended natural gas fuel cannot be dynamically adjusted, which affects the emission performance and economic efficiency of the new energy fuel.

[0007] In order to achieve the above-mentioned purpose, the present invention adopts the following technical scheme: a vehicle hydrogen-blended compressed natural gas supply system and method. This scheme is based on hydrogen cylinders and compressed natural gas cylinders, and a dedicated control pipeline is designed to mix hydrogen and natural gas in any proportion and provide them to the hydrogen-blended compressed natural gas (HCNG) fuel engine, so as to realize the dynamic regulation of hydrogen and natural gas. The gas supply system includes a main pipeline connected to the automobile HCNG engine, and a gaseous natural gas control pipeline and a gaseous hydrogen control pipeline are respectively connected to the other end of the main pipeline; the gaseous natural gas control pipeline includes a compressed natural gas cylinder, and a natural gas flow control valve connected to the outlet end of the compressed natural gas cylinder; the gaseous hydrogen control pipeline includes a hydrogen cylinder, and a hydrogen flow control valve connected to the outlet end of the hydrogen cylinder;

[0008] It also includes a gas filling port, a first one-way valve is provided at the outlet end of the gas filling port, a first high-pressure pressure gauge is provided at the outlet end of the first one-way valve, and the first high-pressure pressure gauge is connected to the inlet end of the compressed natural gas bottle;

[0009] It also includes a hydrogenation port, at the outlet end of which a second one-way valve is provided, at the outlet end of the second one-way valve a second high-pressure pressure gauge is provided, and the second high-pressure pressure gauge is connected to the inlet end of the hydrogen cylinder.

[0010] The principles and advantages of this solution are:

[0011] In the current application of hydrogen-blended natural gas fuel, the combustion characteristics of natural gas will change after hydrogen is blended. Hydrogen has higher combustibility and wider combustion limit, so the natural gas blended with hydrogen burns more quickly and fully. In order to ensure that the engine or combustion equipment can operate stably, it is necessary to predetermine the hydrogen blending ratio so as to adjust the combustion parameters, such as ignition advance angle, fuel injection amount, etc., to adapt to the new combustion characteristics. At the same time, different equipment has different adaptability to hydrogen-blended natural gas. For example, pipeline equipment has certain restrictions on the hydrogen blending ratio. The maximum acceptable hydrogen blending ratio is usually about 10%, while the acceptable hydrogen blending ratio of the pipeline varies with the steel grade, ranging from 30% to 50%. Therefore, before configuring the hydrogen blending ratio in advance, it is necessary to consider the compatibility and limitations of the equipment to ensure the safe operation of the equipment. Therefore, it is generally necessary to predetermine a reasonable hydrogen blending ratio and take corresponding safety measures for mixing. If the mixing ratio is to be changed, the entire system generally needs to be replaced together, resulting in a high cost.

[0012] Moreover, in traditional hydrogen-blended natural gas applications, since the regulated hydrogen-blended natural gas can generally meet the needs of vehicles, and there is no higher regulation demand, there is no consideration of changing the regulation ratio, which increases the workload and instability. More importantly, traditional hydrogen-blended natural gas generally uses industrial hydrogen, not automotive hydrogen. Due to the limitations of industrial hydrogen production, transportation, storage and safe application, it is difficult to achieve real-time dynamic ratio adjustment, and it can only be mixed as a fixed ratio.

[0013] However, with the development and adjustment of automobile technology, as well as the demand for the development and application of new energy, we have found that the application efficiency of hydrogen-blended natural gas for vehicles has always been difficult to improve. Even if the hydrogen blending ratio is continuously increased, it is still difficult to give full play to its combustion characteristics. Research has found that the main reason is not that the higher the hydrogen blending amount, the better, but that the original fixed hydrogen blending ratio fuel is not the optimal ratio for the use environment of each automobile engine, which makes it difficult to further improve its combustion characteristics. Due to the above factors, it is difficult to realize a fuel gas supply system that can flexibly adjust the hydrogen blending ratio based on the existing technology, which has brought the existing new energy vehicle application into a bottleneck.

[0014] Therefore, this solution first uses automotive hydrogen and gaseous high-pressure natural gas as mixed fuels, and uses natural gas cylinders and hydrogen cylinders as storage tanks to store automotive hydrogen and gaseous natural gas. Automotive hydrogen is an emerging energy source in recent years. Compared with industrial hydrogen, it is more suitable for automobile fuel and easier to transport and store, thereby achieving effective hydrogen source supply and convenient storage. Through the natural gas flow control valve and the hydrogen flow control valve, the flow of compressed natural gas and hydrogen can be controlled in real time according to demand, and then the ratio of the mixed gas can be accurately adjusted, which can meet the needs of different hydrogen-blended compressed natural gas (HCNG) fuel engines and the same engine's variable operating conditions, ensuring the safe and reliable operation of the compressed natural gas supply system.

[0015] Secondly, the system cylinder group connection pipeline of this solution adopts parallel / series design, the pipeline design is simple and reliable, the system gas / hydrogen port, one-way valve, and pressure gauge can be combined on one panel, which is highly integrated and modularized to achieve dynamic adjustment operation requirements. The main pipeline is equipped with a high-pressure shut-off valve, high-pressure precision filter and pipeline high-pressure solenoid valve dedicated to the mixed gas (hydrogen / compressed natural gas) to meet the relevant compatibility requirements, so as to meet the long-term use and safety requirements of the system.

[0016] Furthermore, the main pipeline includes a first three-way pipe; the left port of the first three-way pipe is connected to the gaseous natural gas control pipeline, the right port of the first three-way pipe is connected to the gaseous hydrogen control pipeline, the middle port of the first three-way pipe is connected to the inlet end of the high-pressure shut-off valve, the outlet end of the high-pressure shut-off valve is connected to the inlet end of the high-pressure precision filter, and the distance between the high-pressure shut-off valve and the high-pressure precision filter is 1000-2000mm; the outlet end of the high-pressure precision filter is connected to the inlet end of the high-pressure solenoid valve, the distance between the high-pressure precision filter and the high-pressure solenoid valve is 300-1000mm, and the outlet end of the high-pressure solenoid valve is connected to the inlet end of the automobile HCNG engine.

[0017] Furthermore, a hydrogen cylinder valve is provided at the outlet end of the hydrogen cylinder, the outlet end of the hydrogen cylinder valve is connected to the inlet end of the hydrogen flow regulating valve, and a hydrogen pressure sensor is provided on the hydrogen cylinder valve.

[0018] Furthermore, a natural gas cylinder valve is provided at the outlet end of the compressed natural gas cylinder, the outlet end of the natural gas cylinder valve is connected to the inlet end of the natural gas flow regulating valve, and a natural gas pressure sensor is provided on the natural gas cylinder valve.

[0019] Furthermore, a third one-way valve is provided between the first three-way pipe and the natural gas flow regulating valve, and the distance between the natural gas flow regulating valve and the third one-way valve is 100-200 mm; a fourth one-way valve is provided between the first three-way pipe and the hydrogen flow regulating valve, and the distance between the hydrogen flow regulating valve and the fourth one-way valve is 100-200 mm.

[0020] Furthermore, the rated pressure of the CNG cylinder and the hydrogen cylinder is 35 MPa.

[0021] Furthermore, the compressed natural gas cylinder is connected to the natural gas flow regulating valve via a second three-way valve; the hydrogen cylinder is connected to the hydrogen flow regulating valve via a third three-way valve.

[0022] The present invention also provides a method for supplying hydrogen-blended compressed natural gas for vehicles, which is applied to the above-mentioned hydrogen-blended compressed natural gas supply system for vehicles, and dynamically adjusts the ratio of hydrogen and natural gas according to the requirements of the automobile engine, including the following steps:

[0023] Step 1, obtaining initial deployment parameters: collecting the current demand of the automobile HCNG engine, obtaining the current engine's demand for the ratio of hydrogen and natural gas as the initial deployment parameters;

[0024] Step 2, setting current allocation parameters: based on the initial allocation parameters, according to the real-time pressure of gaseous hydrogen and gaseous natural gas, and the real-time acquired vehicle engine demand, determine the real-time flow demand of the current engine for hydrogen and natural gas, and calculate the flow delivery speed demand corresponding to gaseous hydrogen and gaseous natural gas respectively, and adjust the opening value of the flow control valve according to the flow delivery speed demand to output gaseous hydrogen and gaseous natural gas respectively according to the set opening value;

[0025] Step 3, mixed output: the output hydrogen and natural gas are mixed through the main pipeline and then input into the automobile HCNG engine for gas supply.

[0026] Furthermore, the engine demand includes a hydrogen blending ratio and an engine load demand; wherein the hydrogen blending ratio is determined according to the model of the current automobile engine; and the load demand is input by confirming the travel of the accelerator pedal.

[0027] Furthermore, the adjustment parameters are obtained by real-time calculation by the engine ECU according to the hydrogen blending ratio and load demand. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 The present invention is a schematic structural diagram of a vehicle hydrogen-blended compressed natural gas supply system.

[0029] Figure 2 The present invention is a schematic flow chart of a method for supplying hydrogen-blended compressed natural gas for vehicles. DETAILED DESCRIPTION

[0030] The following is further described in detail through specific implementation methods:

[0031] The figure marks in the drawings of the specification include: gas filling port 1, first one-way valve 2, first high-pressure pressure gauge 3, natural gas flow regulating valve 4, hydrogen flow regulating valve 5, hydrogen pressure sensor 6, hydrogen cylinder 7, natural gas pressure sensor 8, hydrogen cylinder valve 9, compressed natural gas cylinder 10, natural gas cylinder valve 11, high-pressure stop valve 12, high-pressure precision filter 13, high-pressure solenoid valve 14, first three-way pipe 15, second three-way valve 16, third one-way valve 17, fourth three-way valve 18, third three-way valve 19, fourth one-way valve 20, hydrogen filling port 21, second one-way valve 22, second high-pressure pressure gauge 23, fifth three-way valve 24.

[0032] Embodiment 1

[0033] This embodiment is basically as shown in the attached Figure 1As shown, a hydrogen-blended compressed natural gas supply system for vehicles uses pipe valves and related gas cylinders that can meet the needs of hydrogen, compressed natural gas, and hydrogen / compressed natural gas mixtures, so as to safely and reliably transport the gaseous hydrogen and gaseous compressed natural gas in the gas cylinders to the hydrogen-blended compressed natural gas (HCNG) fuel engine of the vehicle in different proportions. At present, in order to improve the combustion efficiency of fuel and reduce emissions, hydrogen is added to natural gas vehicles because the combustion speed of hydrogen is faster than that of natural gas (the main component of natural gas is methane). After mixing with hydrogen, the combustion process can be accelerated and the combustion efficiency can be improved. Secondly, the flame propagation speed of hydrogen is much higher than that of natural gas, which helps to burn the mixed gas more evenly and faster, thereby improving the performance of the engine and increasing the power output, thereby reducing the loss of unburned fuel and reducing gas consumption. Thirdly, the combustion temperature of hydrogen is higher, but the nitrogen oxides produced by combustion are less, thereby reducing the generation of nitrogen oxides. More complete combustion also further reduces the emissions of carbon monoxide and hydrocarbons and reduces the emission of harmful gases. Finally, the combustion characteristics of hydrogen make it easier to ignite at low temperatures, which also helps improve the cold start performance of natural gas vehicles, further reducing emissions during cold starts and making it easier to start vehicles in cold weather. Therefore, mixed fuels can effectively improve fuel economy and have better endurance with the same amount of fuel.

[0034] However, due to the high combustion speed and high temperature of hydrogen, existing engine cylinder materials and technologies are not suitable, so pure hydrogen fuel cannot be used, which will lead to low overall efficiency and poor economy of pure hydrogen engines. At the same time, the high price of hydrogen also hinders the promotion of pure hydrogen engines. Therefore, the research and development of mixed fuels is very necessary.

[0035] The gas supply system comprises a main pipe connected to the automobile HCNG engine, and the other end of the main pipe is respectively connected to a gaseous natural gas regulating pipeline and a gaseous hydrogen regulating pipeline.

[0036] In this embodiment, as shown in the attached Figure 1 As shown, the gaseous natural gas control pipeline includes a compressed natural gas bottle 10 and a natural gas flow control valve 4 connected to the outlet end of the compressed natural gas bottle. The natural gas flow control valve 4 is used to adjust the flow of the compressed natural gas in real time to meet the adjustment ratio.

[0037] Specifically, a natural gas cylinder valve 11 is provided at the outlet end of the compressed natural gas cylinder 10. In this embodiment, a high-pressure natural gas pressure sensor 8 is installed on the natural gas cylinder valve 11 to monitor the gas flow pressure in real time. The flow limiting function is realized through the natural gas cylinder valve 11, and the pipeline overcurrent protection is realized in combination with the natural gas pressure sensor 8. If there is a leak or burst in the downstream pipeline, the natural gas cylinder valve 11 can automatically cut off the gas supply to ensure the safety and reliability of the gas supply system.

[0038] The outlet of the natural gas cylinder valve 11 is connected to the inlet of the natural gas flow regulating valve 4 through the second three-way valve 16, and the outlet of the natural gas flow regulating valve 4 is connected to the third one-way valve 17. In this embodiment, the natural gas flow regulating valve 4 is arranged at a distance of 100-200 mm from the third one-way valve 17, and the flow of compressed natural gas can be controlled in real time according to demand through the natural gas flow regulating valve 4 to ensure accurate control and delivery of compressed natural gas.

[0039] It also includes a gas filling port 1, through which the existing gas filling station can be directly connected to deliver compressed natural gas to the compressed natural gas bottle 10 and store it. A first one-way valve 2 is provided at the outlet end of the gas filling port 1, and a first high-pressure pressure gauge 3 is provided at the outlet end of the first one-way valve 2, and the first high-pressure pressure gauge 3 is connected to the inlet end of the compressed natural gas bottle. In this embodiment, the outlet end of the first one-way valve 2 is connected to the left port of the fourth three-way valve 18, the middle port of the fourth three-way valve 18 is connected to the first high-pressure pressure gauge 3, and the right port of the fourth three-way valve 18 is connected to the middle port of the second three-way valve 16. The left port of the second three-way valve 16 is connected to the outlet end of the natural gas bottle valve 11, and the right port of the second three-way valve 16 is connected to the natural gas flow regulating valve 4. Gaseous natural gas flows from the gas filling port 1 to the compressed natural gas bottle 10 and is stored, and then flows to the main pipeline for mixing after being regulated by the natural gas bottle valve 11 and the natural gas flow regulating valve 4.

[0040] The gaseous hydrogen regulating pipeline includes a hydrogen cylinder 7 and a hydrogen flow regulating valve 5 connected to the outlet end of the hydrogen cylinder 7 .

[0041] In this embodiment, a hydrogen bottle valve 9 is provided at the outlet end of the hydrogen bottle 7, and the outlet end of the hydrogen bottle valve 9 is connected to the inlet end of the hydrogen flow regulating valve 5. A hydrogen pressure sensor 6 is also provided on the hydrogen bottle valve 9 to monitor the hydrogen pressure in real time. The hydrogen bottle valve 9 realizes the current limiting function, and the hydrogen pressure sensor 6 is combined to realize the pipeline overcurrent protection. If there is a leak or burst in the downstream pipeline, the hydrogen bottle valve 9 can automatically cut off the gas supply to ensure the safety and reliability of the gas supply system.

[0042] The hydrogen cylinder 7 is connected to the hydrogen flow regulating valve 5 through the third three-way valve 19. In this embodiment, the outlet end of the hydrogen cylinder valve 9 is connected to the right port of the third three-way valve 19, and the left port of the third three-way valve 19 is connected to the inlet end of the hydrogen flow regulating valve 5. The outlet end of the hydrogen flow regulating valve 5 is connected to the fourth one-way valve 20. In this embodiment, the hydrogen flow regulating valve is set at 100-200mm away from the fourth one-way valve 20. The hydrogen flow regulating valve 5 can control the flow of hydrogen in real time according to demand to ensure accurate control and delivery of hydrogen.

[0043] It also includes a hydrogenation port 21, a second one-way valve 22 is provided at the outlet end of the hydrogenation port 21, a second high-pressure pressure gauge 23 is provided at the outlet end of the second one-way valve 22, and the second high-pressure pressure gauge 23 is connected to the inlet end of the hydrogen cylinder. In this embodiment, the outlet end of the second one-way valve 22 is connected to the right port of the fifth three-way valve 24, the middle port of the fifth three-way valve 24 is connected to the second high-pressure pressure gauge 23, and the left port of the fifth three-way valve 24 is connected to the middle port of the third three-way valve 19.

[0044] In this embodiment, the rated pressures of the CNG cylinder 10 and the hydrogen cylinder 7 are both 35 MPa to meet the pressure safety requirements of the system.

[0045] In this embodiment, the main pipeline includes a first three-way pipe 15, the left port of the first three-way pipe 15 is connected to the gaseous natural gas control pipeline, and the right port of the first three-way pipe 15 is connected to the gaseous hydrogen control pipeline. Specifically, the left port of the first three-way pipe 15 is connected to the outlet end of the third one-way valve 17, and the right port of the first three-way pipe 15 is connected to the outlet end of the fourth one-way valve 20, so that the compressed natural gas and hydrogen are mixed and transported to the main pipeline.

[0046] In this embodiment, the middle port of the first three-way pipe 15 is connected to the inlet end of the high-pressure shut-off valve 12, the outlet end of the high-pressure shut-off valve 12 is connected to the inlet end of the high-pressure precision filter 13, the outlet end of the high-pressure precision filter 13 is connected to the inlet end of the high-pressure solenoid valve 14, and the outlet end of the high-pressure solenoid valve 14 is connected to the inlet end of the automobile HCNG engine. In this embodiment, the distance between the high-pressure shut-off valve 12 and the high-pressure precision filter 13 is set to 1000-2000mm, and a pipeline with a diameter of 12.7mm is used in the middle to communicate; the distance between the high-pressure precision filter 13 and the high-pressure solenoid valve 14 is set to 300-1000mm, and a pipeline with a diameter of 12.7mm is used in the middle to communicate. In this way, the safety and stability of the mixed gas during the transportation process are ensured, while ensuring the accuracy of the gas after mixing and reducing losses.

[0047] In this embodiment, each gas transmission pipeline adopts a parallel / series structure, the pipeline structure is simple and reliable, the two pipelines are integrated and modularized, the applicable range is wider, and the operation is safer and more convenient. Through the compressed natural gas flow control valve and the hydrogen flow control valve, the flow of compressed natural gas and hydrogen can be controlled in real time according to demand, and then the mixed gas ratio can be adjusted, which can meet the needs of different hydrogen-blended compressed natural gas (HCNG) fuel engines and the same engine with variable working conditions, becoming the first domestic automobile gas supply system that can dynamically adjust the hydrogen-blended ratio of fuel.

[0048] At the same time, by using a high-pressure stop valve, high-pressure precision filter and pipeline high-pressure solenoid valve dedicated to the mixed gas, the compatibility requirements of the two gases are met, and the long-term use and safety requirements of the system can be met. The pressure sensor can sense the gas pressure in the gas cylinder. When it exceeds the set value, the cylinder valve can be used for safe pressure relief to avoid safety accidents such as gas cylinder explosions, ensuring the safety and stability of system operation.

[0049] Embodiment 2

[0050] This embodiment provides a method for supplying hydrogen-blended compressed natural gas for vehicles, which is applied to the above-mentioned hydrogen-blended compressed natural gas supply system for vehicles, and dynamically adjusts the ratio of hydrogen and natural gas according to the needs of the vehicle engine. Figure 2 As shown, the following steps are included:

[0051] S1, obtain initial deployment parameters.

[0052] The current demand of automobile HCNG engine is collected to obtain the current engine's demand for the ratio of hydrogen and natural gas as the initial allocation parameter input.

[0053] In this embodiment, the initial adjustment parameters are calculated by the engine ECU according to the requirements of the engine and initially set.

[0054] S2, set the current deployment parameters.

[0055] Based on the initial adjustment parameters, the real-time pressures of gaseous hydrogen and gaseous natural gas, as well as the real-time vehicle engine requirements are obtained to determine the real-time flow requirements of the current engine for hydrogen and natural gas, and the flow delivery speed requirements corresponding to the gaseous hydrogen and gaseous natural gas are calculated respectively. The opening value of the flow regulating valve is adjusted according to the flow delivery speed requirements to output the gaseous hydrogen and gaseous natural gas respectively according to the adjusted opening values.

[0056] In this embodiment, the engine demand includes the hydrogen blending ratio and the engine load demand. The hydrogen blending ratio is determined according to the model of the current automobile engine. According to the engine model, the hydrogen blending ratio is generally a fixed value, and different engine models may correspond to different hydrogen blending ratios, so it needs to be determined according to the specific engine model.

[0057] The load demand is input by confirming the stroke of the accelerator pedal. In this embodiment, 0 load corresponds to 0 stroke, and full load corresponds to full stroke. It should be noted that 0 load in this embodiment specifically refers to idle load.

[0058] By obtaining the hydrogen blending ratio and load demand, the current engine demand can be known, so as to set the current deployment parameters. In this embodiment, the engine ECU (electronic control unit) mainly calculates and obtains the hydrogen blending ratio and load demand in real time.

[0059] In this embodiment, the flow requirements of hydrogen and natural gas and the corresponding opening values ​​are mainly measured through engine bench tests to obtain corresponding proportional parameters, so as to obtain the flow delivery speed requirements according to the flow requirements, thereby accurately adjusting the opening value to ensure the accuracy and stability of the delivery volume.

[0060] S3, mixed output.

[0061] The output hydrogen and natural gas are mixed through the main pipeline and then input into the automobile HCNG engine for gas supply.

[0062] In this embodiment, the demand of the automobile engine is obtained in real time, so as to calculate the ratio demand of gaseous hydrogen and gaseous natural gas, and control the opening value of the flow regulating valve accordingly, so that the gaseous hydrogen and gaseous natural gas can be mixed in any proportion and provided to the hydrogen-blended compressed natural gas HCNG fuel engine, and the flow of compressed natural gas and hydrogen can be controlled in real time according to the demand, thereby solving the problem of real-time supply of different proportions of hydrogen and compressed natural gas for hydrogen-blended compressed natural gas fuel vehicles, and effectively improving the emission performance and economic efficiency of compressed natural gas vehicles.

[0063] Embodiment 3

[0064] In this embodiment, the adjustment parameters are dynamically adjusted and set according to the engine requirements. The engine requirements include the hydrogen blending ratio and the engine load requirements. The load requirements also include the engine age, wear degree and usage inertia.

[0065] Based on the engine's service life, the current engine's operating performance can be analyzed to determine the engine's energy consumption ratio and the degree of starting loss, so as to adjust the hydrogen blending ratio suitable for the current engine to reduce starting loss and combustion loss.

[0066] Based on the vehicle's factory information, engine information and vehicle mileage, the current engine wear level can be comprehensively analyzed, thereby analyzing the current engine energy consumption ratio. While minimizing energy consumption, the engine power can be improved, thereby determining the current appropriate hydrogen blending ratio to achieve a better adaptation effect and reduce losses and emissions.

[0067] According to the vehicle's mileage record and the degree of wear and tear of each component and its location, the vehicle's normal operating status during driving can be comprehensively analyzed. For example, if most of the power gears are in the slow gear and the number of starts is high, continuous gas supply is required for starting. At this time, the hydrogen blending ratio can be increased to facilitate rapid starting. If most of the power gears are in the fast gear and the driving is long, the hydrogen blending ratio can be lowered to reduce energy consumption and increase engine power while ensuring that natural gas can be fully burned.

[0068] At the same time, during the driving process of the vehicle, the current power demand of the engine can be analyzed according to the driving road conditions, and the hydrogen blending ratio can be dynamically adjusted according to the power demand, so that the mixed gas fuel ratio can meet the combustion demand of the engine in the current state, while ensuring the full combustion of the fuel and reducing emissions, thereby making the current hydrogen-blended natural gas suitable for the current power driving demand. At the same time, according to the acquired road condition information, the current vehicle vibration degree is analyzed, and the gas flow rate is controlled through the flow control valve to ensure the safety and stability of the mixed gas transmission.

[0069] In this embodiment, since the hydrogen fuel burns quickly and at a high combustion temperature, its combustion endurance is poor and its consumption is high. Natural gas, as the only combustion fuel, will bring about combustion emission problems. Therefore, hydrogen is mixed with natural gas as a mixed fuel. In order to ensure that the engine or fuel equipment can operate stably, the hydrogen mixing ratio needs to be determined in advance in order to adjust the combustion parameters. At the same time, since hydrogen and natural gas are flammable and explosive gases, corresponding safety measures need to be taken during mixing, so it is difficult to change the hydrogen mixing ratio. If it needs to be changed, the entire system usually needs to be replaced.

[0070] And in the original combustion system, since the pre-mixed hydrogen-blended natural gas can also meet most of the vehicle needs, there is no need for higher regulation requirements, and there is no need to consider increasing the workload to regulate the ratio. However, with the strengthening of environmental awareness and energy-saving awareness, it is necessary to further improve the engine power performance and enhance the combustion characteristics of the fuel. After research, it was found that for hydrogen-blended natural gas, even if the hydrogen blending ratio is continuously increased, it is difficult to achieve the optimal combustion characteristics. The main reason is not the amount of hydrogen blending ratio, but the real-time changes in engine demand, which leads to the fact that even if the pre-set hydrogen blending ratio can meet the engine demand, with the use of the engine and the changes in demand in various states, the pre-set hydrogen blending ratio no longer meets the demand, and it is difficult to improve the combustion performance.

[0071] Therefore, this solution simplifies the pipeline design and uses highly safe gas cylinders as mobile storage tanks. After real-time comprehensive analysis of the current engine status, the engine requirements are obtained, so that the current suitable, stable and safe hydrogen blending ratio is allocated according to the demand, and then output after mixing through the main pipeline to ensure the safety and stability of pipeline transportation.

[0072] The above is only an embodiment of the present invention, and the common knowledge such as the known specific technical solutions and / or characteristics in the solution is not described in detail here. It should be pointed out that for those skilled in the art, without departing from the technical solution of the present invention, several modifications and improvements can be made, which should also be regarded as the protection scope of the present invention, and these will not affect the effect of the implementation of the present invention and the practicality of the patent. The scope of protection required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to interpret the content of the claims.

Claims

1. A hydrogen-blended compressed natural gas supply system for vehicles, characterized in that: It includes a main pipe connected to the automobile HCNG engine, and the other end of the main pipe is respectively connected to a gaseous natural gas control pipeline and a gaseous hydrogen control pipeline; the gaseous natural gas control pipeline includes a compressed natural gas bottle, and a natural gas flow control valve connected to the outlet end of the compressed natural gas bottle; the gaseous hydrogen control pipeline includes a hydrogen bottle, and a hydrogen flow control valve connected to the outlet end of the hydrogen bottle; It also includes a gas filling port, a first one-way valve is provided at the outlet end of the gas filling port, a first high-pressure pressure gauge is provided at the outlet end of the first one-way valve, and the first high-pressure pressure gauge is connected to the inlet end of the compressed natural gas bottle; It also includes a hydrogenation port, at the outlet end of which a second one-way valve is provided, at the outlet end of the second one-way valve a second high-pressure pressure gauge is provided, and the second high-pressure pressure gauge is connected to the inlet end of the hydrogen cylinder.

2. A vehicle hydrogen-blended compressed natural gas supply system according to claim 1, characterized in that: The main pipeline includes a first three-way pipe; the left port of the first three-way pipe is connected to the gaseous natural gas control pipeline, the right port of the first three-way pipe is connected to the gaseous hydrogen control pipeline, the middle port of the first three-way pipe is connected to the inlet end of the high-pressure stop valve, the outlet end of the high-pressure stop valve is connected to the inlet end of the high-pressure precision filter, and the distance between the high-pressure stop valve and the high-pressure precision filter is 1000-2000mm; the outlet end of the high-pressure precision filter is connected to the inlet end of the high-pressure solenoid valve, the distance between the high-pressure precision filter and the high-pressure solenoid valve is 300-1000mm, and the outlet end of the high-pressure solenoid valve is connected to the inlet end of the automobile HCNG engine.

3. The vehicle hydrogen-blended compressed natural gas supply system according to claim 1, characterized in that: A hydrogen cylinder valve is also provided at the outlet end of the hydrogen cylinder. The outlet end of the hydrogen cylinder valve is connected to the inlet end of the hydrogen flow regulating valve. A hydrogen pressure sensor is provided on the hydrogen cylinder valve.

4. A vehicle hydrogen-blended compressed natural gas supply system according to claim 1, characterized in that: A natural gas cylinder valve is also provided at the outlet end of the compressed natural gas cylinder. The outlet end of the natural gas cylinder valve is connected to the inlet end of the natural gas flow regulating valve. A natural gas pressure sensor is provided on the natural gas cylinder valve.

5. A vehicle hydrogen-blended compressed natural gas supply system according to claim 2, characterized in that: A third one-way valve is also provided between the first three-way pipe and the natural gas flow regulating valve, and the distance between the natural gas flow regulating valve and the third one-way valve is 100-200mm; a fourth one-way valve is also provided between the first three-way pipe and the hydrogen flow regulating valve, and the distance between the hydrogen flow regulating valve and the fourth one-way valve is 100-200mm.

6. The vehicle hydrogen-blended compressed natural gas supply system according to claim 1, characterized in that: The rated pressure of the CNG cylinder and the hydrogen cylinder is 35 MPa.

7. The vehicle hydrogen-blended compressed natural gas supply system according to claim 1, characterized in that: The compressed natural gas cylinder is connected to the natural gas flow regulating valve via a second three-way valve; the hydrogen cylinder is connected to the hydrogen flow regulating valve via a third three-way valve.

8. A method for supplying hydrogen-blended compressed natural gas for vehicles, characterized in that: A vehicle hydrogen-blended compressed natural gas supply system as claimed in any one of claims 1 to 7, which dynamically adjusts the ratio of hydrogen to natural gas according to the requirements of the vehicle engine, comprises the following steps: Step 1, obtaining initial deployment parameters: collecting the current demand of the automobile HCNG engine, obtaining the current engine's demand for the ratio of hydrogen and natural gas as the initial deployment parameters; Step 2, setting current allocation parameters: based on the initial allocation parameters, according to the real-time pressure of gaseous hydrogen and gaseous natural gas, and the real-time acquired vehicle engine demand, determine the real-time flow demand of the current engine for hydrogen and natural gas, and calculate the flow delivery speed demand corresponding to gaseous hydrogen and gaseous natural gas respectively, and adjust the opening value of the flow control valve according to the flow delivery speed demand to output gaseous hydrogen and gaseous natural gas respectively according to the set opening value; Step 3, mixed output: the output hydrogen and natural gas are mixed through the main pipeline and then input into the automobile HCNG engine for gas supply.

9. A method for supplying hydrogen-blended compressed natural gas for vehicles according to claim 8, characterized in that: The engine requirements include the hydrogen blending ratio and the engine load requirements; wherein the hydrogen blending ratio is determined according to the model of the current automobile engine; and the load requirements are input by confirming the travel of the accelerator pedal.

10. A method for supplying hydrogen-blended compressed natural gas for vehicles according to claim 9, characterized in that: The adjustment parameters are obtained by real-time calculation by the engine ECU according to the hydrogen blending ratio and load demand.

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